bims-meluca 2022-08-07 papers

Front Oncol. 2022 ;12 931104

A novel strategy to fuel cancer immunotherapy: targeting glucose metabolism to remodel the tumor microenvironment.

Xu Liu, Yujie Zhao, Xi Wu, Zhihui Liu, Xiaowei Liu.

The promising results of immunotherapy in tumors have changed the current treatment modality for cancer. However, the remarkable responses are limited to a minority of patients, which is due to immune suppression in the tumor microenvironment (TME). These include the pre-exists of suppressive immune cells, physical barriers to immune infiltration, antigen and antigen presentation deficiency, and expression of inhibitory immune checkpoint molecules. Recently, increasing evidence reveal that tumor metabolism, especially abnormal glucose metabolism of tumors, plays an essential role in tumor immune escape and is a potential target to combine with immunotherapy. By glucose uptake, tumor cells alter their metabolism to facilitate unregulated cellular proliferation and survival and regulate the expression of inhibitory immune checkpoint molecules. Meanwhile, glucose metabolism also regulates the activation, differentiation, and functions of immunocytes. In addition, tumor mainly utilizes glycolysis for energy generation and cellular proliferation, which cause the TME to deplete nutrients for infiltrating immune cells such as T cells and produce immunosuppressive metabolites. Thus, therapeutics that target glucose metabolism, such as inhibiting glycolytic activity, alleviating hypoxia, and targeting lactate, have shown promise as combination therapies for different types of cancer. In this review, we summarized the functions of glucose metabolism in the tumor cells, immune cells, and tumor microenvironment, as well as strategies to target glucose metabolism in combination with immune checkpoint blockade for tumor therapy.

Keywords: aerobic glycolysis; glucose metabolism; immune checkpoint inhibitors; immunotherapy; tumor microenvironment

DOI: https://doi.org/10.3389/fonc.2022.931104

Front Immunol. 2022 ;13 934494

Necroptosis Identifies Novel Molecular Phenotypes and Influences Tumor Immune Microenvironment of Lung Adenocarcinoma.

Chen Zhao, Kewei Xiong, Abdalla Adam, Zhiqiang Ji, Xiangpan Li.

This study aims to investigate the immune and epigenetic mutational landscape of necroptosis in lung adenocarcinoma (LUAD), identify novel molecular phenotypes, and develop a prognostic scoring system based on necroptosis regulatory molecules for a better understanding of the tumor immune microenvironment (TIME) in LUAD. Based on the Cancer Genome Atlas and Gene Expression Omnibus database, a total of 29 overlapped necroptosis-related genes were enrolled to classify patients into different necroptosis phenotypes using unsupervised consensus clustering. We systematically correlated the phenotypes with clinical features, immunocyte infiltrating levels, and epigenetic mutation characteristics. A novel scoring system was then constructed, termed NecroScore, to quantify necroptosis of LUAD by principal component analysis. Three distinct necroptosis phenotypes were confirmed. Two clusters with high expression of necroptosis-related regulators were "hot tumors", while another phenotype with low expression was a "cold tumor". Molecular characteristics, including mutational frequency and types, copy number variation, and regulon activity differed significantly among the subtypes. The NecroScore, as an independent prognostic factor (HR=1.086, 95%CI=1.040-1.133, p<0.001), was able to predict the survival outcomes and show that patients with higher scores experienced a poorer prognosis. It could also evaluate the responses to immunotherapy and chemotherapeutic efficiency. In conclusion, necroptosis-related molecules are correlated with genome diversity in pan-cancer, playing a significant role in forming the TIME of LUAD. Necroptosis phenotypes can distinguish different TIME and molecular features, and the NecroScore is a promising biomarker for predicting prognosis, as well as immuno- and chemotherapeutic benefits in LUAD.

Keywords: immunotherapy; lung adenocarcinoma; multi-omics; necroptosis; tumor immune microenvironment

DOI: https://doi.org/10.3389/fimmu.2022.934494

Front Oncol. 2022 ;12 791496

The Predictive Value of Pretreatment Lactate Dehydrogenase and Derived Neutrophil-to-Lymphocyte Ratio in Advanced Non-Small Cell Lung Cancer Patients Treated With PD-1/PD-L1 Inhibitors: A Meta-Analysis.

Qianning Zhang, Xiaoling Gong, Lei Sun, Liyun Miao, Yujie Zhou.

Background: The Lung Immune Prognostic Index (LIPI) combines the lactate dehydrogenase (LDH) level and the derived neutrophil-to-lymphocyte ratio (dNLR). A lot of studies have shown that LDH and dNLR are associated with the prognosis of advanced non-small cell lung cancer (NSCLC) in patients treated with programmed cell death protein 1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitors. However, previous results were inconsistent, and the conclusions remain unclear. This meta-analysis aimed to investigate the predictive value of pretreatment LDH and dNLR for NSCLC progression in patients treated with PD-1/PD-L1 inhibitors.
Methods: PubMed, Embase, and the Cochrane Library were searched by two researchers independently for related literature before March 2020. Hazard ratios (HRs) with 95% confidence intervals (CIs) for progression-free survival (PFS) and overall survival (OS) were extracted to assess the predictive value of LDH and dNLR. STATA 15. 0 was used to perform the meta-analysis.
Results: A total of 3,429 patients from 26 studies were included in this meta-analysis. The results revealed that high pretreatment LDH was related to poor OS (HR = 1.19, 95%CI = 1.11-1.24, p < 0.001), but not closely related to poor PFS (HR = 1.02, 95%CI = 1.00-1.04, p = 0.023 < 0.05). The pooled results for dNLR suggested that high pretreatment dNLR was related to poor OS (HR = 1.55, 95%CI = 1.33-1.80, p < 0.001) and PFS (HR = 1.33, 95%CI = 1.16-1.54, p < 0.001).
Conclusion: Both pretreatment LDH and dNLR have the potential to serve as peripheral blood biomarkers for patients with advanced NSCLC treated with PD-1/PD-L1 inhibitors. However, more studies on LDH are needed to evaluate its predictive value for PFS in patients with NSCLC.

Keywords: derived neutrophil-to-lymphocyte ratio; immunotherapy; lactate dehydrogenase; non-small cell lung cancer; prognosis

DOI: https://doi.org/10.3389/fonc.2022.791496

Front Pharmacol. 2022 ;13 942261

Exogenous proline enhances susceptibility of NSCLC to cisplatin via metabolic reprogramming and PLK1-mediated cell cycle arrest.

Bingjie Han, Yuanyuan Sun, Xiaofen Zhang, Ping Yue, Meiling Tian, Dan Yan, Fanxiang Yin, Bo Qin, Yi Zhao.

The occurrence of cisplatin resistance is still the main factor limiting the therapeutic effect of non-small cell lung cancer (NSCLC). It is urgent to elucidate the resistance mechanism and develop novel treatment strategies. Targeted metabolomics was first performed to detect amino acids' content in cisplatin-resistant cancer cells considering the relationship between tumour metabolic rearrangement and chemotherapy resistance and chemotherapy resistance. We discovered that levels of most amino acids were significantly downregulated, whereas exogenous supplementation of proline could enhance the sensitivity of NSCLC cells to cisplatin, evidenced by inhibited cell viability and tumour growth in vitro and xenograft models. In addition, the combined treatment of proline and cisplatin suppressed ATP production through disruption of the TCA cycle and oxidative phosphorylation. Furthermore, transcriptomic analysis identified the cell cycle as the top enriched pathway in co-therapy cells, accompanied by significant down-regulation of PLK1, a serine/threonine-protein kinase. Mechanistic studies revealed that PLK1 inhibitor (BI2536) and CDDP have synergistic inhibitory effects on NSCLC cells, and cells transfected with lentivirus expressing shPLK1 showed significantly increased toxicity to cisplatin. Inhibition of PLK1 inactivated AMPK, a primary regulator of cellular energy homeostasis, ultimately leading to cell cycle arrest via FOXO3A-FOXM1 axis mediated transcriptional inhibition in cisplatin-resistant cells. In conclusion, our study demonstrates that exogenous proline exerts an adjuvant therapeutic effect on cisplatin resistance, and PLK1 may be considered an attractive target for the clinical treatment of cisplatin resistance in NSCLC.

Keywords: NSCLC; cisplatin resistance; metabolic reprogramming; plk1; proline

DOI: https://doi.org/10.3389/fphar.2022.942261