bims-meluca Biomed News
on Metabolism of non-small cell lung carcinoma
Issue of 2019‒07‒21
nine papers selected by
Cristina Muñoz Pinedo
L’Institut d’Investigació Biomèdica de Bellvitge


  1. Apoptosis. 2019 Jul 18.
      Sirtuins have emerged as a promising novel class of anti-cancer drug targets. Inhibition of SIRT1 and SIRT2 induces apoptosis in cancer cells and they play multifaceted roles in regulating autophagy. In the present study, we found that salermide, a SIRT1/2-specific inhibitor or small interfering RNAs (siRNAs) to block SIRT1/2 expression could induce autophagy in human NSCLC cells. Moreover, SIRT1/2 inhibition increased the expression levels of ATF4 and DDIT4 and downregulated p-RPS6KB1 and p-EIF4EBP1, two downstream molecules of mTORC1. Moreover, ATF4 or DDIT4 knockdown attenuated salermide-induced autophagy, suggesting that SIRT1/2 inhibition induced autophagy through the ATF4-DDIT4-mTORC1 axis. Mechanistically, SIRT1/2 inhibition led to HSPA5 acetylation and dissociation from EIF2AK3, leading to ER stress response and followed by upregulation of ATF4 and DDIT4, triggering autophagy. Silencing of the autophagic gene ATG5 in lung cancer cells resulted in increased apoptotic cell death induced by SIRT1/2 inhibition. Our data show that inhibition of SIRT1/2 induces pro-survival autophagy via acetylation of HSPA5 and subsequent activation of ATF4 and DDIT4 to inhibit the mTOR signaling pathway in NSCLC cells. These findings suggest that combinatorial treatment with SIRT1/2 inhibitors and pharmacological autophagy inhibitors is an effective therapeutic strategy for cancer therapy.
    Keywords:  ATF4; Autophagy; DDIT4; Sirtuin; mTOR
    DOI:  https://doi.org/10.1007/s10495-019-01559-3
  2. Exp Mol Med. 2019 Jul 17. 51(7): 81
      Chloride intracellular channel 1 (CLIC1) is a promising therapeutic target in cancer due to its intrinsic characteristics; it is overexpressed in specific tumor types and its localization changes from cytosolic to surface membrane depending on activities and cell cycle progression. Ca2+ and reactive oxygen species (ROS) are critical signaling molecules that modulate diverse cellular functions, including cell death. In this study, we investigated the function of CLIC1 in Ca2+ and ROS signaling in A549 human lung cancer cells. Depletion of CLIC1 via shRNAs in A549 cells increased DNA double-strand breaks both under control conditions and under treatment with the putative anticancer agent chelerythrine, accompanied by a concomitant increase in the p-JNK level. CLIC1 knockdown greatly increased basal ROS levels, an effect prevented by BAPTA-AM, an intracellular calcium chelator. Intracellular Ca2+ measurements clearly showed that CLIC1 knockdown significantly increased chelerythrine-induced Ca2+ signaling as well as the basal Ca2+ level in A549 cells compared to these levels in control cells. Suppression of extracellular Ca2+ restored the basal Ca2+ level in CLIC1-knockdown A549 cells relative to that in control cells, implying that CLIC1 regulates [Ca2+]i through Ca2+ entry across the plasma membrane. Consistent with this finding, the L-type Ca2+ channel (LTCC) blocker nifedipine reduced the basal Ca2+ level in CLIC1 knockdown cells to that in control cells. Taken together, our results demonstrate that CLIC1 knockdown induces an increase in the intracellular Ca2+ level via LTCC, which then triggers excessive ROS production and consequent JNK activation. Thus, CLIC1 is a key regulator of Ca2+ signaling in the control of cancer cell survival.
    DOI:  https://doi.org/10.1038/s12276-019-0279-2
  3. Cell Death Dis. 2019 Jul 15. 10(8): 538
      Anticancer chemotherapeutic drugs mainly trigger apoptosis induction to eliminate malignant cells. However, many cancer cells are chemoresistant because of defective apoptosis induction. Targeting the autophagic pathway is currently regarded as an alternative strategy for cancer drug discovery. Penfluridol, an antipsychotic drug, has been reported to exert oncostatic effects, but the effect of penfluridol on lung cancer remains unknown. Herein, the antitumor activity of penfluridol was determined in vitro in non-small-cell lung cancer (NSCLC) cell lines using MTS, plate clonogenic, and transwell migration assays and in vivo in an orthotopic xenograft model. Flow cytometry, holotomographic microscopy, immunofluorescence, and immunohistochemistry were employed to determine the cell-death phenotype induced by penfluridol in vitro and in vivo. Western blotting and genetic knockdown by small interfering RNA were performed to explore the underlying mechanisms involved in penfluridol-mediated cell death. We uncovered that penfluridol inhibited the viability and motility of NSCLC cells in vitro and in vivo. Penfluridol induced nonapoptotic cell death by blocking autophagic flux and inducing accumulation of autophagosome-related protein, light chain 3 (LC3) B-II, in HCC827 and A549 NSCLC cells, and in an A549 orthotopic xenograft tumor model. Autophagosome accumulation-induced cell viability inhibition by penfluridol was mainly attributed to ATP energy deprivation. Moreover, we observed that patients with lung tumors expressing high LC3B had longer overall and disease-free survival times. Mechanistically, upregulation of endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) pathways and activation of p38 mitogen-activated protein kinase (MAPK) were critical for penfluridol-induced autophagosome accumulation. Our findings identify that penfluridol acts as an inducer of ER stress and p38 MAPK activation, which led to UPR-mediated nonapoptotic cell death via autophagosome accumulation-caused energy loss. Penfluridol is clinically used for schizophrenia, and our study results strongly support penfluridol as a repurposed drug for treating NSCLC.
    DOI:  https://doi.org/10.1038/s41419-019-1785-9
  4. Lung Cancer. 2019 Aug;pii: S0169-5002(19)30443-X. [Epub ahead of print]134 42-45
      OBJECTIVES: For patients with Epidermal Growth Factor Receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), frontline EGFR-tyrosine kinase inhibitor (TKI) therapy compared to chemotherapy improves outcomes. However, resistance to these agents uniformly develops. Recently, mutations in the KEAP1-NFE2L2 pathway have been implicated as a potential mechanism of acquired EGFR TKI resistance.MATERIALS AND METHODS: We examined all patients with metastatic NSCLC with mutations in both EGFR and KEAP1/NFE2L2/CUL3 identified on next generation sequencing from 2015 - 2018. These patients were compared to a NSCLC control cohort with mutations in EGFR and wild type in KEAP1/NFE2L2/CUL3 matched on the basis of sex, smoking status, age and race. Time to treatment failure on EGFR TKI therapy and overall survival were examined.
    RESULTS: Among 228 EGFR mutant NSCLCs, 17 (7%) also carried mutations in KEAP1, NFE2L2, or CUL3. The most common co-mutation in both the KEAP1/NFE2L2/CUL3 mutant and wild-type cohort was TP53. Patients with KEAP1/NFE2L2/CUL3 mutations had a shorter median time to treatment failure on EGFR TKI (4.7 months) compared with the wild-type matched cohort (13.0 months), p= 0.0014. There was no difference in overall survival.
    CONCLUSION: For NSCLC patients with mutations in EGFR, co-mutations in KEAP1/NFE2L2/CUL3 are associated with significantly decreased time to treatment failure. Our results suggest that these mutations represent a mechanism of intrinsic resistance to TKI treatment.
    Keywords:  EGFR; KEAP1; NFE2L2; Non-small cell lung cancer; Tyrosine kinase inhibitor
    DOI:  https://doi.org/10.1016/j.lungcan.2019.05.002
  5. Lung Cancer. 2019 Aug;pii: S0169-5002(19)30502-1. [Epub ahead of print]134 180-186
      OBJECTIVES: Positron emission tomography (PET) using 2-deoxy-2-[18F] fluoro-D-glucose (18F-FDG) is a clinically useful modality for cancer evaluation. The mechanism of 18F-FDG uptake within cancer cells involves the glucose transporter 1 (GLUT1) and hypoxia-inducible factor-1 α (HIF-1α). Although recent research has shown its clinical efficacy in small-cell lung cancer (SCLC), no suitable biomarker has been identified. We conducted a clinicopathological study to examine the relationship between tumor immunity and 18F-FDG uptake in patients with SCLC.MATERIALS AND METHODS: Tumor sections were stained by immunohistochemistry for GLUT1, HIF-1α, PD-L1, CD4, CD8, and Foxp3. The relationship between clinicopathological features and 18F-FDG uptake was analyzed. Student's t-test, χ2 test, non-parametric Spearman's rank test, and Kaplan-Meier method were used to evaluate associations between the variables.
    RESULTS: A total of 98 patients 78 men and 20 women who underwent 18F-FDG PET, were enrolled in this study. PD-L1 was expressed in 36.7% (36/98) of all patients; this was significantly associated with GLUT1 expression (p = 0.04). The accumulation of 18F-FDG was significantly higher in patients with low CD8 and CD4 TILs than in those with high TILs (p = 0.03 and p = 0.01, respectively). The uptake of 18F-FDG was not significantly associated with the expression of either Foxp3 or PD-L1. Multivariate analysis demonstrated that advanced stage, poor ECOG-PS, and high SUVmax were independent predictors of poor OS. Among patients with limited-stage disease, multivariate analysis confirmed high PD-L1 expression and a high SUVmax to be independent predictors of poor OS. However, only ECOG-PS was found to be an independent predictor of poor OS among patients with extensive-stage tumors.
    CONCLUSION: High SUVmax on 18F-FDG-PET is correlated with low expression of CD8(+) and CD4(+) TILs, but is an independent prognostic factor for OS, particularly in those with limited disease. Further studies are warranted to validate our findings.
    Keywords:  2-deoxy-2-[18F] fluoro-D-glucose; PD-L1; Positron emission tomography; Small cell lung cancer; Tumor infiltrating lymphocytes
    DOI:  https://doi.org/10.1016/j.lungcan.2019.06.009
  6. Mol Med Rep. 2019 Jul 11.
      Bavachinin (BNN), one of the main active ingredients of Psoraleacorylifolia, can activate peroxisome proliferator‑activated receptor γ (PPARγ). PPARγ has become a promising therapeutic target in cancer. The aim of the present study was to explore the antitumor effects of BNN in non‑small cell lung cancer (NSCLC). Cell Counting Kit‑8 and lactate dehydrogenase release assays were performed to measure cell toxicity. Western blotting and immunofluorescence were used to analyze the expression of apoptosis‑related factors and PPARγ. The ability of PPARγ to bind to BNN was evaluated by drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA). A reactive oxygen species (ROS) assay kit was used to detect the ROS level. The results revealed that the survival rates and cell viability of A549 cells were reduced by BNN in a dose‑dependent manner. The present results also demonstrated that BNN dose‑dependently changed the expression of Bcl‑2, Bax, caspases‑3/9 and PPARγ. In addition, through the cytotoxic and anti‑proliferative effects, the apoptosis‑related proteins' inhibitive properties of BNN were completely inhibited by the PPARγ antagonists T0070907 and GW9662. The DARTS and CETSA results confirmed the protein binding activity of PPARγ. Furthermore, it was demonstrated that the BNN‑induced ROS generation was dependent on PPARγ activation. Taken together, the present study demonstrated that BNN induced the death of A549 cells by activating PPARγ, an effect mediated by the increased ROS level. These results highlighted the potential role of BNN as a chemotherapeutic agent against NSCLC.
    DOI:  https://doi.org/10.3892/mmr.2019.10485
  7. Sci Rep. 2019 Jul 15. 9(1): 10246
      Oscillations in oxygen levels affect malignant cell growth, survival, and metastasis, but also somatic cell behaviour. In this work, we studied the effect of the differential expression of the two primary hypoxia inducible transcription factor isoforms, HIF-1α and HIF-2α, and pulmonary hypoxia to investigate how the hypoxia response of the vascular endothelium remodels the lung pre-metastatic niche. Molecular responses to acute versus chronic tissue hypoxia have been proposed to involve dynamic HIF stabilization, but the downstream consequences and the extent to which differential lengths of exposure to hypoxia can affect HIF-isoform activation and secondary organ pre-disposition for metastasis is unknown. We used primary pulmonary endothelial cells and mouse models with pulmonary endothelium-specific deletion of HIF-1α or HIF-2α, to characterise their roles in vascular integrity, inflammation and metastatic take after acute and chronic hypoxia. We found that acute hypoxic response results in increased lung metastatic tumours, caused by HIF-1α-dependent endothelial cell death and increased microvascular permeability, in turn facilitating extravasation. This is potentiated by the recruitment and retention of specific myeloid cells that further support a pro-metastatic environment. We also found that chronic hypoxia delays tumour growth to levels similar to those seen in normoxia, and in a HIF-2α-specific fashion, correlating with increased endothelial cell viability and vascular integrity. Deletion of endothelial HIF-2α rendered the lung environment more vulnerable to tumour cell seeding and growth. These results demonstrate that the nature of the hypoxic challenge strongly influences the nature of the endothelial cell response, and affects critical parameters of the pulmonary microenvironment, significantly impacting metastatic burden. Additionally, this work establishes endothelial cells as important players in lung remodelling and metastatic progression.
    DOI:  https://doi.org/10.1038/s41598-019-46763-y
  8. Sci Rep. 2019 Jul 15. 9(1): 10163
      Preclinical evidence suggests that stromal expression of platelet-derived growth factor receptors (PDGFRs) stimulates tumor development and diminishes intratumoral drug uptake. In non-small cell lung cancer (NSCLC), the clinical relevance of stromal PDGFR expression remains uncertain. Tumor specimens from 553 patients with primary operable stage I-IIIB NSCLC was obtained and tissue micro-arrays (TMA) were constructed (Norwegian cohort). Immunohistochemistry (IHC) was used to evaluate the expression of PDGFRα and -β in stromal cells and to explore their impact on patient survival. Results were validated in a non-related cohort consisting of TMAs of 367 stage I (A and B) NSCLC patients (Swedish cohort). High stromal PDGFRα expression was an independent predictor of increased survival in the overall populations and SCC (squamous cell carcinoma) subgroups of both investigated cohorts. PDGFRβ was an independent predictor of poor survival in the overall Norwegian cohort and an independent predictor of increased survival in the ADC (adenocarcinoma) subgroup of the Swedish cohort. Tumors displaying the combination PDGFRα-low/PDGFRβ-high exhibited inferior survival according to increasing stage in the Norwegian cohort. This study confirms that high stromal expression of PDGFRα is a predictor of increased survival in NSCLC. Further exploration of the prognostic impact of PDGFRβ and the relationship between PDGFRα and -β is warranted.
    DOI:  https://doi.org/10.1038/s41598-019-46510-3
  9. Curr Opin Support Palliat Care. 2019 Jul 15.
      PURPOSE OF REVIEW: Systemic therapy for lung cancer is increasing in intensity and duration. European nutrition guidelines suggest screening for weight loss and malnutrition, however acknowledges there is a lack of evidence. We discuss current data round this issue and identify opportunities for further research.RECENT FINDINGS: International guidelines now exist to aid the definition of weight loss in cancer, including cachexia, sarcopenia and malnutrition. These allow consistent definition of overlapping, but distinct clinical syndromes. Nutritional status can be assessed in a range of ways including questionnaires, functional assessments, blood markers, physical activity, weight and BMI. Weight loss is commonly associated with a proinflammatory state. Future treatment is likely to be a combination of dietetic support and pharmacological treatment of cachexia.
    SUMMARY: There is a paucity of data on dietetic intervention. It is potentially quick, inexpensive and patient specific, using a holistic approach to aid patients who are malnourished or at risk of malnutrition. Lung cancer-related weight loss is common, further strategies are needed to effectively assess and intervene. Dietetic intervention has the potential to improve patients' quality of life and outcomes.
    DOI:  https://doi.org/10.1097/SPC.0000000000000453