bims-rimeca 2023-03-05 papers

bims-rimeca

Biomed News

on RNA methylation in cancer

Issue of 2023–03–05
25 papers selected by
Sk Ramiz Islam, Saha Institute of Nuclear Physics

Erianin Induces Ferroptosis of Renal Cancer Stem Cells via Promoting ALOX12/P53 mRNA N6-methyladenosine Modification.
METTL3-mediated m6A methylation regulates granulosa cells autophagy during follicular atresia in pig ovaries.
Inhibition of ALKBH5 attenuates I/R-induced renal injury in male mice by promoting Ccl28 m6A modification and increasing Treg recruitment.
LINC00659 cooperated with ALKBH5 to accelerate gastric cancer progression by stabilising JAK1 mRNA in an m6 A-YTHDF2-dependent manner.
Landscape analysis of m6A modification regulators related biological functions and immune characteristics in myasthenia gravis.
The Comprehensive Analysis of N6-Methyadenosine Writer METTL3 and METTL14 in Gastric Cancer.
Transcriptome-wide assessment of N6-methyladenosine modification identifies different gene expression and infection-associated pathways in Treponema pallidum-infected macrophage.
Global loss of cellular m6A RNA methylation following infection with different SARS-CoV-2 variants.
N6-methyladenosine-modified DBT alleviates lipid accumulation and inhibits tumor progression in clear cell renal cell carcinoma through the ANXA2/YAP axis-regulated Hippo pathway.
WTAP regulates autophagy in colon cancer cells by inhibiting FLNA through N6-methyladenosine.
m6A RNA methylation correlates with immune microenvironment and immunotherapy response of melanoma.
METTL3 Promotes Endothelium-Mesenchymal Transition of Pulmonary Artery Endothelial Cells by Regulating TRPC6/Calcineurin/NFAT Signaling Pathways.
Lactoferrin suppresses the progression of colon cancer under hyperglycemia by targeting WTAP/m6A/NT5DC3/HKDC1 axis.
The RNA m5C Methylase NSUN2 Modulates Corneal Epithelial Wound Healing.
Long intergenic non-protein coding RNA 00858 participates in the occurrence and development of esophageal squamous cell carcinoma through the activation of the FTO-m6A-MYC axis by recruiting ZNF184.
ALKBH5-induced circRNA NRIP1 promotes glycolysis in thyroid cancer cells by targeting PKM2.
The roles of N6-methyladenosine and its target regulatory noncoding RNAs in tumors: classification, mechanisms, and potential therapeutic implications.
Identification of m6A regulator-mediated RNA methylation modification patterns and key immune-related genes involved in atrial fibrillation.
Crosstalk between m6A mRNAs and m6A circRNAs and the time-specific biogenesis of m6A circRNAs after OGD/R in primary neurons.
Caprin-1 plays a role in cell proliferation and Warburg metabolism of esophageal carcinoma by regulating METTL3 and WTAP.
GPX3 expression was down-regulated but positively correlated with poor outcome in human cancers.
An integrative analysis of enhancer of yellow 2 homolog (ENY2) as a molecular biomarker in pan-cancer.
Upregulation of miR-192-5p inhibits the ELAVL1/PI3Kδ axis and attenuates microvascular endothelial cell proliferation, migration and angiogenesis in diabetic retinopathy.
EXOC3L1: A Novel Prognostic Biomarker Correlated with Immune Infiltration in Esophageal Squamous Cell Carcinoma.
Mechanism of action of lactic acid on histones in cancer.

J Cancer. 2023 ;14(3): 367-378

Erianin Induces Ferroptosis of Renal Cancer Stem Cells via Promoting ALOX12/P53 mRNA N6-methyladenosine Modification.

Hongliang Shen, Zixiang Geng, Xiaoli Nie, Te Liu.

  Renal cell carcinoma (RCC) is the most common type of primary renal parenchymal malignancy in adults, with a high degree of malignancy and poor prognosis. Human renal cancer stem cells (HuRCSCs) are reported to be the main cause of drug resistance, metastasis, recurrence, and poor prognosis. Erianin is a low molecular-weight bibenzyl natural product extracted from Dendrobium chrysotoxum, which inhibits the in vitro and in vivo activity of a variety of cancer cells. However, the molecular mechanisms of Erianin's therapeutic effect on HuRCSCs are unknown. Here, we isolated CD44+/CD105+ HuRCSCs from patients with renal cell carcinoma. The experiments confirmed that Erianin significantly inhibited the proliferation, invasion, angiogenesis, and tumorigenesis of HuRCSCs, and induced oxidative stress injury and Fe2+ accumulation. qRT-PCR and western blotting showed that Erianin significantly reduced the expression levels of cellular Ferroptosis protective factors, and upregulated the expression of METTL3 and downregulated that of FTO. Dot blotting results indicated that Erianin significantly upregulated the mRNA N6-methyladenosine (m6A) modification of HuRCSCs. The results of RNA immunoprecipitation-PCR also indicated that Erianin significantly enhanced the m6A modification level of the 3' untranslated region of ALOX12 and P53 mRNA in HuRCSCs, resulting in increased stability, prolonged half-life, and improved translation activity. In addition, clinical data analysis showed that the expression of FTO correlated negatively with adverse events in patient with renal cell carcinoma. Thus, this study suggested that Erianin can induce Ferroptosis in renal cancer stem cells by promoting N6-methyladenosine modification of ALOX12/P53 mRNA, ultimately achieving a therapeutic effect on renal cancer.

Keywords:  ALOX12/P53; Erianin; Ferroptosis; N6-methyladenosine (m6A) modification; Renal cancer stem cell

DOI:  https://doi.org/10.7150/jca.81027
Theriogenology. 2023 Feb 23. pii: S0093-691X(23)00064-X. [Epub ahead of print]201 83-94

METTL3-mediated m6A methylation regulates granulosa cells autophagy during follicular atresia in pig ovaries.

Zhengda Li, Ziyun Ruan, Yun Feng, Yanxin Wang, Jun Zhang, Canqiang Lu, Deshun Shi, Fenghua Lu.

  Follicular atresia is a normal physiological event in mammals, yet its mechanism remains to be studied. Granulosa cell (GC) autophagy is closely associated with follicular atresia. The N6-methyladenosine (m6A) modification is the most common post-transcriptional modification in eukaryotes, but its role in follicular atresia is still unknown. In this study, the possible relationship amongst follicular atresia, GC autophagy and m6A modification was studied. Our results showed that the level of autophagy in GCs increased with the degree of follicle atresia, whereas the overall m6A level decreased. Rapamycin treatment induced atresia in vitro cultured follicles, whereas 3-Methyladenine inhibited follicular atresia. Progressed atretic follicle (PAF) GCs had significantly lower METTL3 levels and significantly higher FTO levels than healthy follicle (HF) GCs. Differential gene expression analysis of GCs in PAF and HF by RNA sequencing was showed that the autophagy-related genes ULK1, ULK2, ATG2A, and ATG2B were significantly elevated in the PAF. In cultured GCs, overexpression of METTL3 significantly decreased the mRNA level of ULK1, as well as the autophagy level, whereas knockdown of METTL3 by RNAi significantly increased the mRNA level of ULK1, as well as the autophagy level. Our results indicate that m6A modification can regulate autophagy in GCs and play a role in the process of porcine follicular atresia.

Keywords:  Autophagy; Follicular atresia; Granulosa cell; Pig; m6A modification

DOI:  https://doi.org/10.1016/j.theriogenology.2023.02.021
Nat Commun. 2023 Mar 01. 14(1): 1161

Inhibition of ALKBH5 attenuates I/R-induced renal injury in male mice by promoting Ccl28 m6A modification and increasing Treg recruitment.

Juntao Chen, Cuidi Xu, Kun Yang, Rifeng Gao, Yirui Cao, Lifei Liang, Siyue Chen, Shihao Xu, Ruiming Rong, Jina Wang, Tongyu Zhu.

Ischemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI). The role of N6-methyladenosine (m6A) modification in AKI remains unclear. Here, we characterize the role of AlkB homolog 5 (ALKBH5) and m6A modification in an I/R-induced renal injury model in male mice. Alkbh5-knockout mice exhibit milder pathological damage and better renal function than wild-type mice post-IRI, whereas Alkbh5-knockin mice show contrary results. Also conditional knockout of Alkbh5 in the tubular epithelial cells alleviates I/R-induced AKI and fibrosis. CCL28 is identified as a target of ALKBH5. Furthermore, Ccl28 mRNA stability increases with Alkbh5 deficiency, mediating by the binding of insulin-like growth factor 2 binding protein 2. Treg recruitment is upregulated and inflammatory cells are inhibited by the increased CCL28 level in IRI-Alkbh5fl/flKspCre mice. The ALKBH5 inhibitor IOX1 exhibits protective effects against I/R-induced AKI. In summary, inhibition of ALKBH5 promotes the m6A modifications of Ccl28 mRNA, enhancing its stability, and regulating the Treg/inflammatory cell axis. ALKBH5 and this axis is a potential AKI treatment target.

DOI: https://doi.org/10.1038/s41467-023-36747-y
Clin Transl Med. 2023 Mar;13(3): e1205

LINC00659 cooperated with ALKBH5 to accelerate gastric cancer progression by stabilising JAK1 mRNA in an m6 A-YTHDF2-dependent manner.

Yuan Fang, Xi Wu, Yunru Gu, Run Shi, Tao Yu, Yutian Pan, Jingxin Zhang, Xinming Jing, Pei Ma, Yongqian Shu.

BACKGROUND: N6-methyladenosine (m6 A) RNA modification is known as a common epigenetic regulation form in eukaryotic cells. Emerging studies show that m6 A in noncoding RNAs makes a difference, and the aberrant expression of m6 A-associated enzymes may cause diseases. The demethylase alkB homologue 5 (ALKBH5) plays diverse roles in different cancers, but its role during gastric cancer (GC) progression is not well known.
METHODS: The quantitative real-time polymerase chain reaction, immunohistochemistry staining and western blotting assays were used to detect ALKBH5 expression in GC tissues and human GC cell lines. The function assays in vitro and xenograft mouse model in vivo were used to investigate the effects of ALKBH5 during GC progression. RNA sequencing, MeRIP sequencing, RNA stability and luciferase reporter assays were performed to explore the potential molecular mechanisms involved in the function of ALKBH5. RNA binding protein immunoprecipitation sequencing (RIP-seq), RIP and RNA pull-down assays were performed to examine the influence of LINC00659 on the ALKBH5-JAK1 interaction.
RESULTS: ALKBH5 was highly expressed in GC samples and associated with aggressive clinical features and poor prognosis. ALKBH5 promoted the abilities of GC cell proliferation and metastasis in vitro and in vivo. The m6 A modification on JAK1 mRNA was removed by ALKBH5, which resulted in the upregulated expression of JAK1. LINC00659 facilitated ALKBH5 binding to and upregulated JAK1 mRNA depending on an m6 A-YTHDF2 manner. Silencing of ALKBH5 or LINC00659 disrupted GC tumourigenesis via the JAK1 axis. JAK1 upregulation activated the JAK1/STAT3 pathway in GC.
CONCLUSION: ALKBH5 promoted GC development via upregulated JAK1 mRNA expression mediated by LINC00659 in an m6 A-YTHDF2-dependent manner, and targeting ALKBH5 may be a promising therapeutic method for GC patients.

DOI: https://doi.org/10.1002/ctm2.1205
J Transl Med. 2023 Mar 02. 21(1): 166

Landscape analysis of m6A modification regulators related biological functions and immune characteristics in myasthenia gravis.

Shuang Li, Hui Liu, Zhe Ruan, Rongjing Guo, Chao Sun, Yonglan Tang, Xiaoxi Huang, Ting Gao, Sijia Hao, Huanhuan Li, Na Song, Yue Su, Fan Ning, Zhuyi Li, Ting Chang.

   BACKGROUND: N6-methyladenosine (m6A) modification has been recognized to play fundamental roles in the development of autoimmune diseases. However, the implication of m6A modification in myasthenia gravis (MG) remains largely unknown. Thus, we aimed to systematically explore the potential functions and related immune characteristics of m6A regulators in MG.
METHODS: The GSE85452 dataset with MG and healthy samples was downloaded from Gene Expression Omnibus (GEO) database. m6A modification regulators were manually curated. The targets of m6A regulators were obtained from m6A2Target database. The differential expressed m6A regulators in GSE85452 dataset were identified by "limma" package and were validated by RT-PCR. Function enrichment analysis of dysregulated m6A regulators was performed using "clusterProfiler" package. Correlation analysis was applied for analyzing the relationships between m6A regulators and immune characteristics. Unsupervised clustering analysis was used to identify distinct m6A modification subtypes. The differences between subtypes were analyzed, including the expression level of all genes and the enrichment degree of immune characteristics. Weighted gene co-expression network analysis (WGCNA) was conducted to obtain modules associated with m6A modification subtypes.
RESULTS: We found that CBLL1, RBM15 and YTHDF1 were upregulated in MG samples of GSE85452 dataset, and the results were verified by RT-PCR in blood samples from19 MG patients and 19 controls. The targeted genes common modified by CBLL1, RBM15, and YTHDF1 were mainly enriched in histone modification and Wnt signaling pathway. Correlation analysis showed that three dysregulated m6A regulators were closely associated with immune characteristics. Among them, RBM15 possessed the strongest correlation with immune characteristics, including CD56dim natural killer cell (r = 0.77, P = 0.0023), T follicular helper cell (r = - 0.86, P = 0.0002), Interferon Receptor (r = 0.78, P = 0.0017), and HLA-DOA (r = 0.64, P = 0.0200). Further two distinct m6A modification patterns mediated by three dysregulated m6A regulators was identified. Bioinformatics analysis found that there were 3029 differentially expressed genes and different immune characteristics between two m6A modification patterns. Finally, WGCNA analysis obtained a total of 12 modules and yellow module was the most positively correlated to subtype-2.
CONCLUSION: Our findings suggested that m6A RNA modification had an important effect on immunity molecular mechanism of MG and provided a new perspective into understanding the pathogenesis of MG.

Keywords:  Correlation analysis; Immune characteristics; Myasthenia gravis; WGCNA; m6A modification

DOI:  https://doi.org/10.1186/s12967-023-03947-5
J Oncol. 2023 ;2023 9822995

The Comprehensive Analysis of N6-Methyadenosine Writer METTL3 and METTL14 in Gastric Cancer.

Yiling Ge, Yihan Zhang, Sheng Yang, Tong Liu, Tianyi Zhang, Yanlu Feng, Chuntao Wang, Geyu Liang.

Methyltransferase-like 3 (METTL3) and methyltransferase-like 14 (METTL14) were two core components of the N6-methyadenosine (m6A) methyltransferase complex (MTC) and played a basic role in maintaining an appropriate m6A level of target genes. In gastric cancer (GC), previous researches on the expression and role of METTL3 and METTL14 were not consistent, and their specific function and mechanism have remained elusive. In this study, the expression of METTL3 and METTL14 was evaluated based on the TCGA database, 9 paired GEO datasets, and our 33 GC patient samples, and METTL3 was highly expressed and acted as a poor prognostic factor, whereas METTL14 showed no significant difference. Moreover, GO and GSEA analyses were performed, and the results pointed out that METTL3 and METTL14 were jointly involved in multiple biological processes, while they could also take part in different oncogenic pathways independently. And BCLAF1 was predicted and identified as a novel shared target of METTL3 and METTL14 in GC. In total, we conducted a comprehensive analysis of METTL3 and METTL14 in GC including their expression, function, and role, which could provide a novel insight into the research of m6A modification in GC.

DOI: https://doi.org/10.1155/2023/9822995
J Dermatol Sci. 2023 Feb 19. pii: S0923-1811(23)00060-9. [Epub ahead of print]

Transcriptome-wide assessment of N6-methyladenosine modification identifies different gene expression and infection-associated pathways in Treponema pallidum-infected macrophage.

Zhijia Li, Litian Zhang, Yinbo Jiang, Xiaoxin Lin, Yuhui Liao, Bin Yang, Muzhou Teng.

   BACKGROUND: Treponema pallidum (Tp) is a widespread and destructive pathogen that leads to syphilis. As the acknowledged executor of host immunity, macrophage plays vital roles in combating the invasion and migration of Tp. However, the mechanisms of these processes are largely unknown, especially the critical driver genes and associated modifications.
OBJECTIVE: We aimed to systematically dissect the global N6-methyladenosine (m6A) RNA modification patterns in Tp-infected macrophages.
METHODS: The RNA of Tp-infected/non-infected macrophage was extracted, followed by mRNA sequencing and methylated RNA immunoprecipitation (MeRIP) sequencing. Bioinformatics analysis was executed by m6A peaks and motifs identification, Gene ontology and signaling pathways analysis of differentially expressed genes, and comprehensive comparison. The m6A levels were measured by RNA Methylation Assay, and m6A modified genes were determined by qPCR.
RESULTS: Totally, 2623 unique and 3509 common m6A peaks were proved along with related transcripts in Tp-infected macrophages. The common m6A-related genes were enriched in the signals of oxidative stress, cell differentiation, and angiogenesis, while unique genes in those of metabolism, inflammation, and infection. And differentially expressed transcripts revealed various biological processes and pathways associated with catabolic and infection. They also experienced comprehensive analysis due to hyper-/hypo-methylation. And the m6A level of macrophage was elevated, along with qPCR validation of specific genes.
CONCLUSION: With a particular m6A transcriptome-wide map, our study provides unprecedented insights into the RNA modification of macrophage stimulated by Tp in vitro, which partially differs from other infections and may provide clues to explore the immune process for syphilis.

Keywords:  Infection-associated pathways; Macrophage; MeRIP-seq; N6-methyladenosine modification; RNA-seq; Treponema pallidum

DOI:  https://doi.org/10.1016/j.jdermsci.2023.02.004
Genome Res. 2023 Mar 01. pii: gr.276407.121. [Epub ahead of print]

Global loss of cellular m6A RNA methylation following infection with different SARS-CoV-2 variants.

Roshan Vaid, Akram Mendez, Ketan Thombare, Rebeca Burgos Panadero, Rémy Robinot, Barbara F Fonseca, Nikhil R Gandasi, Johan Ringlander, Mohammad Hassan Baig, Jae-June Dong, Jae Yong Cho, Björn Reinius, Lisa A Chakrabarti, Kristina Nystrom, Tanmoy Mondal.

Host-viral interactions during SARS-CoV-2 infection are needed to understand COVID-19 pathogenesis and may help to guide the design of novel antiviral therapeutics. N6-methyladenosine modification (m6A), one of the most abundant cellular RNA modifications, regulates key processes in RNA metabolism during a stress response. Gene expression profiles observed post-infection with different SARS-CoV-2 variants show changes in the expression of genes related to RNA catabolism, including m6A readers and erasers. We found that infection with SARS-CoV-2 variants caused a loss of m6A in cellular RNAs, whereas m6A was detected abundantly in viral RNA. METTL3, the m6A methyltransferase, showed an unusual cytoplasmic localization post-infection. The B.1.351 variant had a less pronounced effect on METTL3 localization and loss of m6A than the B.1 and B.1.1.7 variants. We also observed a loss of m6A upon SARS-CoV-2 infection in air/liquid interface cultures of human airway epithelia, confirming that m6A loss is characteristic of SARS-CoV-2 infected cells. Further, transcripts with m6A modification were preferentially down-regulated post-infection. Inhibition of the export protein XPO1 resulted in the restoration of METTL3 localization, recovery of m6A on cellular RNA, and increased mRNA expression. Stress granule formation, which was compromised by SARS-CoV-2 infection, was restored by XPO1 inhibition and accompanied by a reduced viral infection in vitro. Together, our study elucidates how SARS-CoV-2 inhibits the stress response and perturbs cellular gene expression in an m6A-dependent manner.

DOI: https://doi.org/10.1101/gr.276407.121
Cancer Commun (Lond). 2023 Mar 01.

N6-methyladenosine-modified DBT alleviates lipid accumulation and inhibits tumor progression in clear cell renal cell carcinoma through the ANXA2/YAP axis-regulated Hippo pathway.

Daojia Miao, Qi Wang, Jian Shi, Qingyang Lv, Diaoyi Tan, Chuanyi Zhao, Zhiyong Xiong, Xiaoping Zhang.

   BACKGROUND: The mechanism of metabolism reprogramming is an unsolved problem in clear cell renal cell carcinoma (ccRCC). Recently, it was discovered that the Hippo pathway altered tumor metabolism and promoted tumor progression. Thus, this study aimed at identifying key regulators of metabolism reprogramming and the Hippo pathway in ccRCC and pinpointing potential therapeutic targets for ccRCC patients.
METHODS: Hippo-related gene sets and metabolic gene sets were used to screen potential regulators of the Hippo pathway in ccRCC. Public databases and samples from patients were applied to investigate the association of dihydrolipoamide branched chain transacylase E2 (DBT) with ccRCC and Hippo signaling. The role of DBT was confirmed by gain or loss of function assays in vitro and in vivo. Mechanistic results were yielded by luciferase reporter assay, immunoprecipitation, mass spectroscopy, and mutational studies.
RESULTS: DBT was confirmed as a Hippo-related marker with significant prognostic predictive value, and its downregulation was caused by methyltransferase-like-3 (METTL3)-mediated N6-methyladenosine (m6 A) modification in ccRCC. Functional studies specified DBT as a tumor suppressor for inhibiting tumor progression and correcting the lipid metabolism disorder in ccRCC. Mechanistic findings revealed that annexin A2 (ANXA2) interacted with the lipoyl-binding domain of DBT to activate Hippo signaling which led to decreased nuclear localization of yes1-associated transcriptional regulator (YAP) and transcriptional repression of lipogenic genes.
CONCLUSIONS: This study demonstrated a tumor-suppressive role for the DBT/ANXA2/YAP axis-regulated Hippo signaling and suggested DBT as a potential target for pharmaceutical intervention in ccRCC.

Keywords:  Hippo signaling; N6-methyladenosine; clear cell renal cell carcinoma; dihydrolipoamide branched chain transacylase E2; lipid accumulation

DOI:  https://doi.org/10.1002/cac2.12413
Cell Adh Migr. 2023 Dec;17(1): 1-13

WTAP regulates autophagy in colon cancer cells by inhibiting FLNA through N6-methyladenosine.

Liang Huang, Jinfan Shao, Xijuan Xu, Weiwen Hong, Wenfeng Yu, Shuang Zheng, Xiaogang Ge.

  Our study investigated the role of WTAP in colon cancer. We employed experiments including m6A dot blot hybridization, methylated RNA immunoprecipitation, dual-luciferase, and RNA immunoprecipitation to investigate the regulatory mechanism of WTAP. Western blot was performed to analyze the expression of WTAP, FLNA and autophagy-related proteins in cells. Our results confirmed the up-regulation of WTAP in colon cancer and its promoting effect on proliferation and inhibiting effect on apoptosis. FLNA was the downstream gene of WTAP and WTAP-regulated m6A modification led to post-transcriptional repression of FLNA. The rescue experiments showed that WTAP/FLNA could inhibit autophagy. WTAP-mediated m6A modification was confirmed to be crucial in colon cancer development, providing new insights into colon cancer therapy.

Keywords:  FLNA; WTAP; autophagy; colon cancer; m6A

DOI:  https://doi.org/10.1080/19336918.2023.2180196
J Invest Dermatol. 2023 Feb 24. pii: S0022-202X(23)00095-7. [Epub ahead of print]

m6A RNA methylation correlates with immune microenvironment and immunotherapy response of melanoma.

Gaofeng Wang, Dongqiang Zeng, Evan Sweren, Yong Miao, Ruosi Chen, Junjun Chen, Jin Wang, Wangjun Liao, Zhiqi Hu, Sewon Kang, Luis A Garza.

RNA methylation normally inhibits self-recognition and immunogenicity of RNA. As such, it is likely an important inhibitor of cancer immune recognition in the tumor microenvironment (TME), but how N6-methyladenosine (m6A) affects prognosis and treatment response remains unknown. In eight independent melanoma cohorts (1564 patients), the modification patterns of 21 m6A gene signatures were systematically correlated with the immune cell infiltration of melanoma TME. m6A modification patterns for each patient were quantified using the principal component analysis (PCA) method, yielding an m6Ascore that reflects the abundance of m6A RNA modifications. Two different m6A modification patterns were observed in melanoma patients, separated into high and low m6Ascores that correlated with survival and treatment response. Low m6Ascores were characterized by an immune-inflamed phenotype, with 61.1% five-year survival. High m6Ascores were characterized by an immune-excluded phenotype, with 52.2% five-year survival. Importantly, lower m6Ascores correlated with more sensitive anti-PD1 and anti-CTLA4 treatment responses, with 90% of patients with low m6Ascore responding while 10% of those with high m6Ascore non-responding (in cohort GSE63557). At single-cell and spatial transcriptome resolution, m6Ascore reflects melanoma malignant progression, immune exhaustion, and resistance to ICB therapy. Hence, the m6Ascore correlates to an important facet of tumor immune escape as a tool for personalized medicine to guide immunotherapy in melanoma patients.

DOI: https://doi.org/10.1016/j.jid.2023.01.027
Evid Based Complement Alternat Med. 2023 ;2023 8269356

METTL3 Promotes Endothelium-Mesenchymal Transition of Pulmonary Artery Endothelial Cells by Regulating TRPC6/Calcineurin/NFAT Signaling Pathways.

Chunchu Kong, Fuxiu Zhang, Ruicheng Hu, Lile Wang.

Background: Endothelium-mesenchymal transition (EndMT) is a process of phenotypic and functional transition from activated endothelial cells to mesenchymal cells. Recently, EndMT has been proved to be one of the main pathological mechanisms of pulmonary artery hypertension (PAH). However, the molecular mechanism is not clear.
Methods: Primary rat pulmonary arterial endothelial cells (rPAECs) were isolated from Sprague-Dawley rats and verified by CD31 immunofluorescence staining. rPAECs were exposed to hypoxic conditions to induce EndMT. RNA and protein levels in cells were detected by RT-qPCR and Western blot. The migration ability was verified by the transwell assay. The RIP experiment was used to test the m6A modification of TRPC6 mRNA and the binding relationship between TRPC6 and METTL3. Calcineurin/NFAT signaling was measured by using commercial kits.
Results: METTL3 was found to be highly expressed by hypoxia treatment in a time-dependent manner. Knockdown of METTL3 significantly suppressed cell migration, downregulated the levels of interstitial cell-related markers like α-SMA and vimentin, and increased the levels of endothelial cell markers including CD31 and VE-cadherin. Mechanistically, METTL3 increased TRPC6 expression by enhancing the m6A modification of TRPC6 mRNA, thus activating calcineurin/NFAT signaling. Our experiments showed that METTL3 silencing mediated the inhibitory roles in the hypoxia-mediated EndMT process, which were significantly reversed by TRPC6/calcineurin/NFAT signaling activation.
Conclusion: Our results elucidated that METTL3 knockdown inhibited the hypoxia-mediated EndMT process by inactivating TRPC6/calcineurin/NFAT signaling.

DOI: https://doi.org/10.1155/2023/8269356
J Transl Med. 2023 Feb 28. 21(1): 156

Lactoferrin suppresses the progression of colon cancer under hyperglycemia by targeting WTAP/m6A/NT5DC3/HKDC1 axis.

Huiying Li, Chaonan Li, Boyang Zhang, Hongpeng Jiang.

   BACKGROUND: Although the relationship between type 2 diabetes (T2D) and the increased risk of colorectal carcinogenesis is widely defined in clinical studies, the therapeutic methods and molecular mechanism of T2D-induced colon cancer and how does hyperglycemia affect the progression is still unknown. Here, we studied the function of lactoferrin (LF) in suppressing the progression of colon cancer in T2D mice, and uncovered the related molecular mechanisms in DNA 5mC and RNA m6A levels.
METHODS: We examined the effects of LF (50% iron saturation) on the migration and invasion of colon tumor cells under high concentration of glucose. Then, transcriptomics and DNA methylation profilings of colon tumor cells was co-analyzed to screen out the special gene (NT5DC3), and the expression level of NT5DC3 in 75 clinical blood samples was detected by q-PCR and western blot, to investigate whether NT5DC3 was a biomarker to distinguish T2D patients and T2D-induced colon cancer patients from healthy volunteers. Futhermore, in T2D mouse with xenografted colon tumor models, the inhibitory effects of LF and NT5DC3 protein on colon tumors were investigated. In addition, epigenetic alterations were measured to examine the 5mC/m6A modification sites of NT5DC3 regulated by LF. Utilizing siRNA fragments of eight m6A-related genes, the special gene (WTAP) regulating m6A of NT5DC was proved, and the effect of LF on WTAP/NT5DC3/HKDC1 axis was finally evaluated.
RESULTS: A special gene NT5DC3 was screened out through co-analysis of transcriptomics and DNA methylation profiling, and HKDC1 might be a downstream sensor of NT5DC3. Mechanistically, LF-dependent cellular DNA 5mC and RNA m6A profiling remodeling transcriptionally regulate NT5DC3 expression. WTAP plays a key role in regulating NT5DC3 m6A modification and subsequently controls NT5DC3 downstream target HKDC1 expression. Moreover, co-treatment of lactoferrin and NT5DC3 protein restrains the growth of colon tumors by altering the aberrant epigenetic markers. Strikingly, clinical blood samples analysis demonstrates NT5DC3 protein expression is required to direct the distinction of T2D or T2D-induced colon cancer with healthy humans.
CONCLUSIONS: Together, this study reveals that lactoferrin acts as a major factor to repress the progression of colon cancer under hyperglycemia, thus, significantly expanding the landscape of natural dietary mediated tumor suppression.

Keywords:  Colon cancer; Lactoferrin (LF); NT5DC3; RNA m6A; Type 2 diabetes (T2D)

DOI:  https://doi.org/10.1186/s12967-023-03983-1
Invest Ophthalmol Vis Sci. 2023 Mar 01. 64(3): 5

The RNA m5C Methylase NSUN2 Modulates Corneal Epithelial Wound Healing.

Guangying Luo, Weiwei Xu, Xiaoyan Chen, Wenji Xu, Shuai Yang, Jiao Wang, Yong Lin, Peter S Reinach, Dongsheng Yan.

Purpose: The emerging epitranscriptomics offers insights into the physiopathological roles of various RNA modifications. The RNA methylase NOP2/Sun domain family member 2 (NSUN2) catalyzes 5-methylcytosine (m5C) modification of mRNAs. However, the role of NSUN2 in corneal epithelial wound healing (CEWH) remains unknown. Here we describe the functional mechanisms of NSUN2 in mediating CEWH.
Methods: RT-qPCR, Western blot, dot blot, and ELISA were used to determine the NSUN2 expression and overall RNA m5C level during CEWH. NSUN2 silencing or overexpression was performed to explore its involvement in CEWH both in vivo and in vitro. Multi-omics was integrated to reveal the downstream target of NSUN2. MeRIP-qPCR, RIP-qPCR, and luciferase assay, as well as in vivo and in vitro functional assays, clarified the molecular mechanism of NSUN2 in CEWH.
Results: The NSUN2 expression and RNA m5C level increased significantly during CEWH. NSUN2 knockdown significantly delayed CEWH in vivo and inhibited human corneal epithelial cells (HCEC) proliferation and migration in vitro, whereas NSUN2 overexpression prominently enhanced HCEC proliferation and migration. Mechanistically, we found that NSUN2 increased ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) translation through the binding of RNA m5C reader Aly/REF export factor. Accordingly, UHRF1 knockdown significantly delayed CEWH in vivo and inhibited HCEC proliferation and migration in vitro. Furthermore, UHRF1 overexpression effectively rescued the inhibitory effect of NSUN2 silencing on HCEC proliferation and migration.
Conclusions: NSUN2-mediated m5C modification of UHRF1 mRNA modulates CEWH. This finding highlights the critical importance of this novel epitranscriptomic mechanism in control of CEWH.

DOI: https://doi.org/10.1167/iovs.64.3.5
Genomics. 2023 Mar 01. pii: S0888-7543(23)00037-X. [Epub ahead of print] 110593

Long intergenic non-protein coding RNA 00858 participates in the occurrence and development of esophageal squamous cell carcinoma through the activation of the FTO-m6A-MYC axis by recruiting ZNF184.

Shun Ke, Jing Wang, Jun Lu, Minghao Fang, Ruichao Li.

   OBJECTIVES: We aimed at probing impact of LINC00858 on esophageal squamous cell carcinoma (ESCC) progression via ZNF184-FTO-m6A-MYC axis.
METHODS: Expression of related genes (LINC00858, ZNF184, FTO, and MYC) was detected in ESCC tissues or cells and their relationships were assessed. After expression alterations in ESCC cells, cell proliferation, invasion, migration, and apoptosis were detected. Tumor formation in nude mice was conducted.
RESULTS: LINC00858, ZNF184, FTO, and MYC were overexpressed in ESCC tissues and cells. LINC00858 enhanced ZNF184 expression to upregulate FTO, which augmented MYC expression. LINC00858 knockdown diminished ESCC cell proliferative, migratory, and invasive properties while elevating apoptosis, which was negated by FTO overexpression. FTO knockdown exerted similar functions of LINC00858 knockdown on ESCC cell movements, which was annulled by MYC upregulation. Silencing LINC00858 repressed tumor growth and related gene expression in nude mice.
CONCLUSIONS: LINC00858 modulated MYC m6A modification via FTO by recruiting ZNF184, thus facilitating ESCC progression.

Keywords:  Esophageal squamous cell carcinoma; FTO; Long intergenic non-protein coding RNA 00858; MYC; ZNF184; m(6)A

DOI:  https://doi.org/10.1016/j.ygeno.2023.110593
Cancer Sci. 2023 Feb 27.

ALKBH5-induced circRNA NRIP1 promotes glycolysis in thyroid cancer cells by targeting PKM2.

Xiaoyu Ji, Chengzhou Lv, Jiapeng Huang, Wenwu Dong, Wei Sun, Hao Zhang.

  Although circular RNAs are involved in cell proliferation, differentiation, apoptosis, and invasion, the underlying regulatory mechanisms of circular RNAs in thyroid cancer have not been fully elucidated. This article aimed to study the role of circRNA regulated by N6-methyladenosine modification in papillary thyroid cancer (PTC). Quantitative real-time PCR, western blotting, and immunohistochemistry were used to investigate the expressions of circular RNA nuclear receptor-interacting protein 1 (circNRIP1) in PTC tissues and adjacent non-cancerous thyroid tissues. In vitro and in vivo assays were performed to assess the effects of circNRIP1 on PTC glycolysis and growth. The N6-methyladenosine mechanisms of circNRIP1 were evaluated via methylated RNA immunoprecipitation sequencing, luciferase reporter gene, and RNA stability assays. Results showed that CircNRIP1 levels were significantly up-regulated in PTC tissues. Furthermore, elevated circNRIP1 levels in PTC patients were correlated with high tumor lymph node metastasis stage and larger tumor sizes. Functionally, circNRIP1 significantly promoted glycolysis, PTC cell proliferation in vitro, and tumorigenesis in vivo. Mechanistically, circNRIP1 acted as a sponge for miR-541-5p and miR-3064-5p and jointly up-regulated pyruvate kinase M2 (PKM2) expressions. Knockdown of m6 A demethylase α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) significantly enhanced circNRIP1 m6 A modification and up-regulated its expressions. These results show that ALKBH5 knockdown up-regulates circNRIP1, thus promoting glycolysis in PTC cells. Therefore, circNRIP1 can be a prognostic biomarker and therapeutic target for PTC by acting as a sponge for oncogenic miR-541-5p and miR-3064-5p to up-regulate PKM2 expressions.

Keywords:  Glycolysis; PKM2; PTC; circNRIP1; m6A

DOI:  https://doi.org/10.1111/cas.15772
Exp Mol Med. 2023 Mar 01.

The roles of N6-methyladenosine and its target regulatory noncoding RNAs in tumors: classification, mechanisms, and potential therapeutic implications.

Ziying Liu, Lei Gao, Long Cheng, Gaoyuan Lv, Bei Sun, Gang Wang, Qiushi Tang.

N6-methyladenosine (m6A) is one of the epigenetic modifications of RNA. The addition of this chemical mark to RNA molecules regulates gene expression by affecting the fate of the RNA molecules. This posttranscriptional RNA modification is reversible and regulated by methyltransferase "writers" and demethylase "erasers". The fate of m6A-modified RNAs depends on the function of different "readers" that recognize and bind to them. Research on m6A methylation modification has recently increased due to its important role in regulating cancer progression. Noncoding RNAs (ncRNAs) are a class of RNA molecules that are transcribed from the genome but whose roles have been overlooked due to their lack of well-defined potential for translation into proteins or peptides. However, this misconception has now been completely overturned. ncRNAs regulate various diseases, especially tumors, and it has been confirmed that they play either tumor-promoting or tumor-suppressing roles in almost all types of tumors. In this review, we discuss the m6A modification of different types of ncRNA and summarize the mechanisms involved. Finally, we discuss the progress of research on clinical treatment and discuss the important significance of the m6A modification of ncRNAs in the clinical treatment of tumors.

DOI: https://doi.org/10.1038/s12276-023-00944-y
Aging (Albany NY). 2023 Feb 20. 15

Identification of m6A regulator-mediated RNA methylation modification patterns and key immune-related genes involved in atrial fibrillation.

Peng-Fei Zheng, Sen-Yu Zhou, Chang-Qing Zhong, Zhao-Fen Zheng, Zheng-Yu Liu, Hong-Wei Pan, Jian-Qiang Peng.

  The role of m6A in the regulation of the immune microenvironment in atrial fibrillation (AF) remains unclear. This study systematically evaluated the RNA modification patterns mediated by differential m6A regulators in 62 AF samples, identified the pattern of immune cell infiltration in AF and identified several immune-related genes associated with AF. A total of six key differential m6A regulators between healthy subjects and AF patients were identified by the random forest classifier. Three distinct RNA modification patterns (m6A cluster-A, -B and -C) among AF samples were identified based on the expression of 6 key m6A regulators. Differential infiltrating immune cells and HALLMARKS signaling pathways between normal and AF samples as well as among samples with three distinct m6A modification patterns were identified. A total of 16 overlapping key genes were identified by weighted gene coexpression network analysis (WGCNA) combined with two machine learning methods. The expression levels of the NCF2 and NCST genes were different between controls and AF patient samples as well as among samples with the distinct m6A modification patterns. RT-qPCR also proved that the expression of NCF2 and NCST was significantly increased in AF patients compared with control participants. These results suggested that m6A modification plays a key role in the complexity and diversity of the immune microenvironment of AF. Immunotyping of patients with AF will help to develop more accurate immunotherapy strategies for those with a significant immune response. The NCF2 and NCST genes may be novel biomarkers for the accurate diagnosis and immunotherapy of AF.

Keywords:  NCF2; NCST; atrial fibrillation; immune microenvironment; m6A

DOI:  https://doi.org/10.18632/aging.204537
Epigenetics. 2023 Dec;18(1): 2181575

Crosstalk between m6A mRNAs and m6A circRNAs and the time-specific biogenesis of m6A circRNAs after OGD/R in primary neurons.

Chi Zhang, Huan Jian, Shenghui Shang, Lu Lu, Yongfu Lou, Yi Kang, Hong Bai, Zheng Fu, Yigang Lv, Xiaohong Kong, Xueying Li, Shiqing Feng, Hengxing Zhou.

  Cerebral ischaemiareperfusion injury is an important pathological process in nervous system diseases during which neurons undergo oxygenglucose deprivation and reoxygenation (OGD/R) injury. No study has used epitranscriptomics to explore the characteristics and mechanism of injury. N6methyladenosine (m6A) is the most abundant epitranscriptomic RNA modification. However, little is known about m6A modifications in neurons, especially during OGD/R. m6A RNA immunoprecipitation sequencing (MeRIPseq) and RNA-sequencing data for normal and OGD/R-treated neurons were analysed by bioinformatics. MeRIP quantitative real-time polymerase chain reaction was used to determine the m6A modification levels on specific RNAs. We report the m6A modification profiles of the mRNA and circRNA transcriptomes of normal and OGD/R-treated neurons. Expression analysis revealed that the m6A levels did not affect m6A mRNA or m6A circRNA expression. We found crosstalk between m6A mRNAs and m6A circRNAs and identified three patterns of m6A circRNA production in neurons; thus, distinct OGD/R treatments induced the same genes to generate different m6A circRNAs. Additionally, m6A circRNA biogenesis during distinct OGD/R processes was found to be time specific. These results expand our understanding of m6A modifications in normal and OGD/R-treated neurons, providing a reference to explore epigenetic mechanisms and potential treatments for OGD/R-related diseases.

Keywords:  Epitranscriptomics; N6-methyladenosine; OGD/R; circRNA; neuron

DOI:  https://doi.org/10.1080/15592294.2023.2181575
J Transl Med. 2023 Feb 28. 21(1): 159

Caprin-1 plays a role in cell proliferation and Warburg metabolism of esophageal carcinoma by regulating METTL3 and WTAP.

Yan Gao, Lingling Yuan, Changbin Ke, Zhijun Pei, Xiaobo Liu, Ruimin Wu, Xueyan Kui, Yanmin Zhang.

   BACKGROUND: Cytoplasmic activation/proliferation-associated protein-1 (Caprin-1) is implicated in cancer cell proliferation and tumorigenesis; however, its role in the development of esophageal carcinoma (ESCA) has not been examined.
METHODS: Biological methods and data analysis were used to investigate the expression of Caprin-1 in ESCA tissue and cell lines. We comprehensively analyzed the mRNA expression and prognostic values, signalling pathways of CAPRIN1 in ESCA using public databases online. Biological functions of CAPRIN1 were performed by clorimetric growth assay, EdU staining, colony formation, flow cytometry, apoptosis analysis, Western blot, lactate detection assay, extracellular acidification rates. The underlying mechanism was determined via flow cytometric analysis, Western blot and rescue experiments. In addition, xenograft tumor model was constructed to verify the phenotypes upon CAPRIN1 silencing.
RESULTS: Caprin-1 expression was significantly elevated in both ESCA tumor tissues and cell lines compared with that in normal adjacent tissues and fibroblasts. Increased CAPRIN1 mRNA expression was significantly associated with clinical prognosis and diagnostic accuracy. The GO enrichment and KEGG pathway analysis CAPRIN1 might be related to immune-related terms, protein binding processes, and metabolic pathways. A significant positive correlation was observed between high Caprin-1 protein levels and lymph node metastasis (P = 0.031), ki-67 (P = 0.023), and 18F- FDG PET/CT parameters (SUVmax (P = 0.002) and SUV mean (P = 0.005)) in 55 ESCA patients. At cut-off values of SUVmax 17.71 and SUVmean 10.14, 18F- FDG PET/CT imaging predicted Caprin-1 expression in ESCA samples with 70.8% sensitivity and 77.4% specificity. In vitro and in vivo assays showed that Caprin-1 knockdown affected ESCA tumor growth. Silencing Caprin-1 inhibited ESCA cell proliferation and glycolysis, and decreased the expression of methyltransferase-like 3 (METTL3) and Wilms' tumor 1-associating protein (WTAP). However, this effect could be partially reversed by the restoration of METTL3 and WTAP expression.
CONCLUSIONS: Our data suggest that Caprin-1 could serve as a prognostic biomarker and has an oncogenic role in ESCA.

Keywords:  18F-FDG-PET; Caprin-1; Esophageal carcinoma; Glucose metabolism; Methyltransferase-like 3; Wilms’ tumor 1-associating protein

DOI:  https://doi.org/10.1186/s12967-023-04001-0
Front Oncol. 2023 ;13 990551

GPX3 expression was down-regulated but positively correlated with poor outcome in human cancers.

Qingyi Hu, Jiaoshun Chen, Wen Yang, Ming Xu, Jun Zhou, Jie Tan, Tao Huang.

   Introduction: Cancer is a crucial public health problem and one of the leading causes of death worldwide. Previous studies have suggested that GPX3 may be involved in cancer metastasis and chemotherapy resistance. However, how GPX3 affects cancer patients' outcomes and the underlying mechanism remains unclear.
Methods: Sequencing data and clinical data from TCGA, GTEx, HPA, and CPTAC were used to explore the relationship between GPX3 expression and clinical features. Immunoinfiltration scores were used to assess the relationship between GPX3 and the tumor immune microenvironment. Functional enrichment analysis was used to predict the role of GPX3 in tumors. Gene mutation frequency, methylation level, and histone modification were used to predict the GPX3 expression regulation method. Breast, ovarian, colon, and gastric cancer cells were used to investigate the relationship between GPX3 expression and cancer cell metastasis, proliferation, and chemotherapy sensitivity.
Results: GPX3 is down-regulated in various tumor tissues, and GPX3 expression level can be used as a marker for cancer diagnosis. However, GPX3 expression is associated with higher stage and lymph node metastasis, as well as poorer prognosis. GPX3 is closely related to thyroid function and antioxidant function, and its expression may be regulated by epigenetic inheritance such as methylation modification or histone modification. In vitro experiments, GPX3 expression is associated with cancer cell sensitivity to oxidant and platinum-based chemotherapy and is involved in tumor metastasis in oxidative environments.
Discussion: We explored the relationship between GPX3 and clinical features, immune infiltration characteristics, migration and metastasis, and chemotherapy sensitivities of human cancers. We further investigated the potential genetic and epigenetic regulation of GPX3 in cancer. Our results suggested that GPX3 plays a complicated role in the tumor microenvironment, simultaneously promoting metastasis and chemotherapy resistance in human cancers.

Keywords:  GPX3; chemotherapy resistance; glutathione peroxidase; metastasis; pan-cancer; tumor microenvironment (TME)

DOI:  https://doi.org/10.3389/fonc.2023.990551
Funct Integr Genomics. 2023 Mar 02. 23(1): 72

An integrative analysis of enhancer of yellow 2 homolog (ENY2) as a molecular biomarker in pan-cancer.

Qi Chen, Xiao Shi, Yuanyuan Bao, Guanyu Sun, Shu Wu, Yue Chen.

  ENY2 (Enhancer of yellow 2 transcription factor) is a transcription nuclear protein and primarily participates in the course of mRNA export and histone deubiquitination to influence gene expression. Current studies have shown that the expression of ENY2 is significantly upregulated in multiple cancers. However, the exact association between ENY2 and pan-cancers has not been fully established. Here, we comprehensively analyzed ENY2 from the online public database and The Cancer Genome Atlas (TCGA) database, including gene expression level in pan-cancer, comparison of ENY2 expression in different molecular and immune subtypes of pan-cancer, targeted protein, biological functions, molecular signatures, diagnostic and prognostic value in pan-cancer. Moreover, we focused on head and neck squamous cell carcinoma (HNSC) and explored ENY2 from the perspective of the correlations with clinical characteristics, prognosis, co-expression genes, differentially expressed genes (DEGs) and immune Infiltration. Our findings showed that the expression of ENY2 differed enormously not only in most cancer types but also in different molecular and immune subtypes of cancers. High accuracy in predicting cancers and notable correlations with prognosis of certain cancers suggested that ENY2 might be a potential diagnostic and prognostic biomarker of cancers. In addition, ENY2 was identified to be significantly correlated with clinical stage, gender, histologic grade and lymphovascular invasion in HNSC. Overexpression of ENY2 could lead to a worse overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI) in HNSC, especially in different clinical subgroups of HNSC. Taken together, ENY2 showed strong correlation with the diagnosis and prognosis of pan-cancer, and was an independent prognostic risk factor of HNSC, which may serve as a potential target for cancer management.

Keywords:  ENY2; Head and neck squamous cell carcinoma (HNSC); Molecular biomarker; Pan-cancer; Prognostic biomarker

DOI:  https://doi.org/10.1007/s10142-023-01000-8
Diabet Med. 2023 Mar 02. e15077

Upregulation of miR-192-5p inhibits the ELAVL1/PI3Kδ axis and attenuates microvascular endothelial cell proliferation, migration and angiogenesis in diabetic retinopathy.

Xiao-Lin Fu, Fu-Tao He, Mo-Han Li, Chun-Yan Fu, Jian-Zhi Chen.

   BACKGROUND: Diabetic retinopathy (DR) is a common complication of diabetes mellitus that poses a threat to adults. MicroRNAs (miRNAs) play a key role in DR progression. However, the role and mechanism of miR-192-5p in DR remain unclear. We aimed to investigate the effect of miR-192-5p on cell proliferation, migration and angiogenesis in DR.
METHODS: Expression of miR-192-5p, ELAV-like RNA binding protein 1 (ELAVL1) and phosphoinositide 3-kinase delta (PI3Kδ) in human retinal fibrovascular membrane (FVM) samples and human retinal microvascular endothelial cells (HRMECs) was assessed using RT-qPCR. ELAVL1 and PI3Kδ protein levels were evaluated by Western blot. RIP and dual luciferase reporter assays were performed to confirm the miR-192-5p/ELAVL1/PI3Kδ regulatory networks. Cell proliferation, migration and angiogenesis were assessed by CCK8, transwell and tube formation assays.
RESULTS: MiR-192-5p was decreased in FVM samples from DR patients and high glucose (HG)-treated HRMECs. Functionally, overexpressed miR-192-5p inhibited cell proliferation, migration and angiogenesis in HG-treated HRMECs. Mechanically, miR-192-5p directly targeted ELAVL1 and decreased its expression. We further verified that ELAVL1 bound to PI3Kδ and maintained PI3Kδ mRNA stability. Rescue analysis demonstrated that the suppressive effects of HG-treated HRMECs caused by miR-192-5p upregulation were overturned by overexpressed ELAVL1 or PI3Kδ.
CONCLUSION: MiR-192-5p attenuates DR progression by targeting ELAVL1 and reducing PI3Kδ expression, suggesting a biomarker for the treatment of DR.

Keywords:  ELAVL1; PI3Kδ; diabetic retinopathy; miR-192-5p; microvascular endothelial cell

DOI:  https://doi.org/10.1111/dme.15077
Med Sci Monit. 2023 Feb 17. 29 e938512

EXOC3L1: A Novel Prognostic Biomarker Correlated with Immune Infiltration in Esophageal Squamous Cell Carcinoma.

Zhan-Fei Zhang.

BACKGROUND Exocyst complex component 3-like 1 (EXOC3L1) is ubiquitously present in multiple organs. However, its role in esophageal squamous cell carcinoma (ESCC) remains unknown. The aim of this study was to explore the relationship between EXOC3L1 and ESCC. MATERIAL AND METHODS A total of 652 normal samples and 82 ESCC samples obtained from the University of California Santa Cruz (UCSC) Xena were applied to detect the expression difference of EXOC3L1. GSE53625 with 179 paired samples and GSE161533 with 28 paired samples were used for validation. The correlation between clinicopathological features and EXOC3L1 expression was calculated. Kaplan-Meier method was employed to assess the prognostic value of EXOC3L1 in ESCC. Univariate and multivariate Cox regression analyses were carried out to screen the factors contributing to the prognosis of ESCC. In addition, functional enrichment analysis, protein-protein interaction (PPI) network analysis, and immune infiltration analysis were conducted to identify the significantly involved functions of EXOC3L1. RESULTS EXOC3L1 was significantly overexpressed in ESCC compared to normal samples. High expression of EXOC3L1 was associated with worse prognosis, and univariate and multivariate Cox regression analysis demonstrated that EXOC3L1 was an independent prognostic predictor of ESCC. Functional enrichment analysis and immune infiltration analysis disclosed that the expression of EXOC3L1 was correlated with the abundance of several types of immune cells. CONCLUSIONS EXOC3L1 plays a crucial role in the prognosis of ESCC, and it may serve as a reliable biomarker for predicting the survival and a potential therapeutic target for ESCC.

DOI: https://doi.org/10.12659/MSM.938512
Antioxid Redox Signal. 2023 Feb 27.

Mechanism of action of lactic acid on histones in cancer.

Riccardo Sgarra, Sabrina Battista, Laura Cerchia, Guidalberto Manfioletti, Monica Fedele.

SIGNIFICANCE: Metabolic end products and intermediates can exert signaling functions as chemical sources for histone post-translational modifications, which remodel chromatin and affect gene expression. Among them, lactic acid is responsible for histone lactylation, a recently discovered histone mark that occurs in high lactate conditions, such as those resulting from the Warburg effect in cancer cells.
RECENT ADVANCES: Late-breaking studies have advanced the knowledge on the mechanisms involved in histone lactylation, requiring independent non-enzyme-dependent and enzyme-dependent reactions, which is emerging as an important hallmark of cancer cells linking metabolic changes to gene expression reprogramming.
CRITICAL ISSUES: Here, we give an overview about this new epigenetic modification, focusing on its mechanism of action in tumors and tumor microenvironment.
FUTURE DIRECTIONS: Further investigation on the competition mechanism between lactylation and acetylation, as well as on the mechanisms by which lactate fluctuation can control a specific gene set in a given tissue are needed in the coming years to exploit new anti-cancer therapeutic approaches.

DOI: https://doi.org/10.1089/ars.2022.0190