bims-meluca 2024-02-18 papers

Cancer Res. 2024 Feb 16.

Decoding Serine Metabolism: Unveiling Novel Pathways for Evolving Cancer Therapies.

Aristotle Lau, John Blenis, Guillermo Burgos-Barragan.

Serine metabolism plays a pivotal role in cancer, making it an appealing therapeutic target. Two recent studies published in Nature Metabolism and Science Translational Medicine uncovered novel players and therapeutic opportunities within this crucial metabolic pathway. Papalazarou and colleagues employed genetic tools coupled with metabolomics and high-throughput imaging to identify and characterize membrane transporters involved in serine uptake and mitochondrial import in colorectal cancer. Notably, they showed that dual inhibition of these transporters in combination with impaired serine biosynthesis reduced tumor growth in xenograft models. In a parallel study, Zhang and colleagues identified isocitrate dehydrogenase I (IDH1) as a novel regulator of serine biosynthesis in non-small cell lung cancer (NSCLC). Through extensive mechanistic studies, they demonstrated that IDH1 enhances the expression of the key enzymes phosphoglycerate dehydrogenase (PHGDH) and phosphoserine aminotransferase 1 (PSAT1) via a non-canonical function independent of its enzymatic activity. Strikingly, pharmacological disruption of this novel function of IDH1 not only diminished tumor growth but also enhanced the anticancer efficacy of dietary serine restriction in mouse models of lung cancer. Together, these studies advance our mechanistic understanding of how cancer cells fulfill their serine requirements and reveal innovative therapeutic avenues to deprive tumors of this vital nutrient.

DOI: https://doi.org/10.1158/0008-5472.CAN-24-0541

Proc Natl Acad Sci U S A. 2024 Feb 20. 121(8): e2317343121

Cysteine induces mitochondrial reductive stress in glioblastoma through hydrogen peroxide production.

Evan K Noch, Laura Palma, Isaiah Yim, Nayah Bullen, Daniel Barnett, Alexander Walsh, Bhavneet Bhinder, Elisa Benedetti, Jan Krumsiek, Justin Gurvitch, Sumaiyah Khwaja, Daphne Atlas, Olivier Elemento, Lewis C Cantley.

Glucose and amino acid metabolism are critical for glioblastoma (GBM) growth, but little is known about the specific metabolic alterations in GBM that are targetable with FDA-approved compounds. To investigate tumor metabolism signatures unique to GBM, we interrogated The Cancer Genome Atlas for alterations in glucose and amino acid signatures in GBM relative to other human cancers and found that GBM exhibits the highest levels of cysteine and methionine pathway gene expression of 32 human cancers. Treatment of patient-derived GBM cells with the FDA-approved single cysteine compound N-acetylcysteine (NAC) reduced GBM cell growth and mitochondrial oxygen consumption, which was worsened by glucose starvation. Normal brain cells and other cancer cells showed no response to NAC. Mechanistic experiments revealed that cysteine compounds induce rapid mitochondrial H2O2 production and reductive stress in GBM cells, an effect blocked by oxidized glutathione, thioredoxin, and redox enzyme overexpression. From analysis of the clinical proteomic tumor analysis consortium (CPTAC) database, we found that GBM cells exhibit lower expression of mitochondrial redox enzymes than four other cancers whose proteomic data are available in CPTAC. Knockdown of mitochondrial thioredoxin-2 in lung cancer cells induced NAC susceptibility, indicating the importance of mitochondrial redox enzyme expression in mitigating reductive stress. Intraperitoneal treatment of mice bearing orthotopic GBM xenografts with a two-cysteine peptide induced H2O2 in brain tumors in vivo. These findings indicate that GBM is uniquely susceptible to NAC-driven reductive stress and could synergize with glucose-lowering treatments for GBM.

Keywords: cysteine; glioblastoma; hydrogen peroxide; mitochondrial metabolism; reductive stress

DOI: https://doi.org/10.1073/pnas.2317343121

Lung Cancer. 2024 Feb 08. pii: S0169-5002(24)00035-7. [Epub ahead of print]189 107502

HLA-I levels correlate with survival outcomes in response to immune checkpoint inhibitors in non-small cell lung cancer.

Maria Saigí, Jose L Mate, Enric Carcereny, Anna Martínez-Cardús, Anna Esteve, Felipe Andreo, Carmen Centeno, Marc Cucurull, Ricard Mesia, Eva Pros, Montse Sanchez-Cespedes.

OBJECTIVES: Immune checkpoint inhibitors (ICIs) have provided a breakthrough in the treatment of non-small cell lung cancer (NSCLC) patients, but only some patients benefit substantively. Identifying definitive predictive biomarkers could overcome this limitation.
MATERIALS AND METHODS: We selected 146 metastatic NSCLC patients treated with anti-PD-(L)1. Immunohistochemistry of HLA-I, PD-L1 and CD73 was performed in 122 tumor biopsies at diagnosis. The association with patients, tumor parameters, and the predictive value to ICI treatment were determined.
RESULTS: In our cohort, 42 %, 25 %, and 21 % of the tumors exhibited high levels of HLA-I, PD-L1, and CD73, respectively. Lung adenocarcinomas displayed elevated CD73 levels, compared with lung squamous cell carcinomas (P = 0.026). High PD-L1 was significantly correlated with high levels of HLA-I (P = 0.005) and of CD73 (P = 0.025). Patients with high-level HLA-I tumors exhibited more favorable clinical outcomes following ICI, with a median overall survival of 30.7 months (95 % confidence interval [CI]: 18.3 months-not reached), compared with 18.2 months (95 % CI: 12.4-25.2 months) in patients with low-level HLA-I tumors (P = 0.016). The median progression-free survival (PFS) for patients with high-level HLA-I tumors was 18.5 months (95 % CI: 11.1-57.1 months), longer than patients with low-level HLA-I tumors, whose median PFS was 9.2 months (95 % CI: 7.2-11.9 months) (P = 0.006). In a multivariable analysis, high-level HLA-I was independently associated with lower risk of progression to ICI (HR = 0.46, 95 % CI 0.24-0.87; P = 0.018).
CONCLUSIONS: High-level HLA-I were associated with better clinical outcomes to ICI in our cohort of NSCLC patients. Therefore, further investigations are warranted to refine this biomarker and validate its efficacy in prospective and larger set of patients.

Keywords: CD73; HLA-I; Immune checkpoint inhibitors; Non-small cell lung cancer; PD-L1

DOI: https://doi.org/10.1016/j.lungcan.2024.107502

Discov Oncol. 2024 Feb 16. 15(1): 37

The endoplasmic reticulum stress-related genes and molecular typing predicts prognosis and reveals characterization of tumor immune microenvironment in lung squamous cell carcinoma.

Ruolan Wang, Yanhua Huang, Juan He, Shan Jin, Xin Li, Kun Tan, Wei Xia.

BACKGROUND: Endoplasmic reticulum stress (ERS) acts critical roles on cell growth, proliferation, and metastasis in various cancers. However, the relationship between ERs and lung squamous cell carcinoma (LUSC) prognoses still remains unclear.
METHODS: The consensus clustering analysis of ERS-related genes and the differential expression analysis between clusters were investigated in LUSC based on TCGA database. Furthermore, ERS-related prognostic risk models were constructed by LASSO regression and Cox regression analyses. Then, the predictive effect of the risk model was evaluated by Kaplan-Meier, Cox regression, and ROC Curve analyses, as well as validated in the GEO cohort. According to the optimal threshold, patients with LUSC were divided into high- and low- risk groups, and somatic mutations, immune cell infiltration, chemotherapy response and immunotherapy effect were systematically analyzed.
RESULTS: Two ERS-related clusters were identified in patients with LUSC that had distinct patterns of immune cell infiltration. A 5-genes ERS-related prognostic risk model and nomogram were constructed and validated. Kaplan-Meier curves and Cox regression analysis showed that ERS risk score was an independent prognostic factor (p < 0.001, HR = 1.317, 95% CI = 1.159-1.496). Patients with low-risk scores presented significantly lower TIDE scores and significantly lower IC50 values for common chemotherapy drugs such as cisplatin and gemcitabine.
CONCLUSION: ERS-related risk signature has certain prognostic value and may be a potential therapeutic target and prognostic biomarker for LUSC patients.

Keywords: Endoplasmic reticulum stress; Lung squamous cell carcinoma (LUSC); Prognosis; Tumor immune microenvironment

DOI: https://doi.org/10.1007/s12672-024-00887-4

Front Oncol. 2024 ;14 1303543

Impact of the response to platinum-based chemotherapy on the second-line immune checkpoint inhibitor monotherapy in non-small cell lung cancer with PD-L1 expression ≤49%: a multicenter retrospective study.

Introduction: The efficacy of second-line immune checkpoint inhibitor (ICI) therapy is limited in non-small cell lung cancer (NSCLC) patients with ≤ 49% PD-L1 expression. Although chemoimmunotherapy is a promising strategy, platinum-based chemotherapy followed by ICI monotherapy is often used to avoid synergistic adverse events. However, predictors of the efficacy of ICI monotherapy after platinum-based chemotherapy in NSCLC with ≤ 49% PD-L1 expression remain scarce.
Methods: This multicenter retrospective study evaluated 54 advanced or recurrent NSCLC patients with ≤ 49% PD-L1 expression who were treated with second-line ICI monotherapy following disease progression on first-line platinum-based chemotherapy at nine hospitals in Japan. The impact of response to platinum-based chemotherapy on the efficacy of subsequent ICI monotherapy was investigated.
Results: The response to first-line platinum-based chemotherapy was divided into two groups: the non-progressive disease (PD) group, which included patients who did not experience disease progression after four cycles of chemotherapy, and the PD group, which included patients who showed initial PD or could not maintain disease control during the four cycles of chemotherapy and switched to second-line ICI monotherapy. Among the 54 patients, 32 and 22 were classified into the non-PD and PD groups, respectively. The non-PD group showed better response rates (p = 0.038) and longer overall survival (OS) with ICI monotherapy (p = 0.023) than the PD group. Multivariate analysis identified that maintaining a non-PD status after four cycles of chemotherapy was an independent prognostic factor for ICI monotherapy (p = 0.046). Moreover, patients with a modified Glasgow Prognostic Score (mGPS) of 0 showed a tendency for longer OS with ICI monotherapy (p = 0.079), and there was a significant correlation between maintaining non-PD after four cycles of chemotherapy and an mGPS of 0 (p = 0.045).
Conclusion: Maintaining a non-PD status after four cycles of platinum-based chemotherapy was a predictor of OS after second-line ICI monotherapy. These findings will help physicians select the most suitable treatment option for NSCLC patients who were treated with platinum-based chemotherapy and switched to second-line treatment. Those who experienced early PD during platinum-based chemotherapy should not be treated with ICI monotherapy in the second-line setting.

Keywords: immune checkpoint inhibitor monotherapy; modified Glasgow prognostic score; non-small cell lung cancer; platinum-based chemotherapy; predictive marker

DOI: https://doi.org/10.3389/fonc.2024.1303543