Hsa_circ_0096157 silencing suppresses autophagy and reduces cisplatin resistance in non-small cell lung cancer by weakening the Nrf2/ARE signaling pathway.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the leading cause of cancer morbidity and mortality worldwide, and new diagnostic markers are urgently needed. We aimed to investigate the mechanism by which hsa_circ_0096157 regulates autophagy and cisplatin (DDP) resistance in NSCLC. METHODS: A549 cells were treated with DDP (0 µg/mL or 3 µg/mL). Then, the autophagy activator rapamycin (200 nm) was applied to the A549/DDP cells. Moreover, hsa_circ_0096157 and Nrf2 were knocked down, and Nrf2 was overexpressed in A549/DDP cells. The expression of Hsa_circ_0096157, the Nrf2/ARE pathway-related factors Nrf2, HO-1, and NQO1, and the autophagy-related factors LC3, Beclin-1, and p62 was evaluated by qRT‒PCR or western blotting. Autophagosomes were detected through TEM. An MTS assay was utilized to measure cell proliferation. The associated miRNA levels were also tested by qRT‒PCR. RESULTS: DDP (3 µg/mL) promoted hsa_circ_0096157, LC3 II/I, and Beclin-1 expression and decreased p62 expression. Knocking down hsa_circ_0096157 resulted in the downregulation of LC3 II/I and Beclin-1 expression, upregulation of p62 expression, and decreased proliferation. Rapamycin reversed the effect of interfering with hsa_circ_0096157. Keap1 expression was lower, and Nrf2, HO-1, and NQO1 expression was greater in the A549/DDP group than in the A549 group. HO-1 expression was repressed after Nrf2 interference. In addition, activation of the Nrf2/ARE pathway promoted autophagy in A549/DDP cells. Moreover, hsa_circ_0096157 activated the Nrf2/ARE pathway. The silencing of hsa_circ_0096157 reduced Nrf2 expression by releasing miR-142-5p or miR-548n. Finally, we found that hsa_circ_0096157 promoted A549/DDP cell autophagy by activating the Nrf2/ARE pathway. CONCLUSION: Knockdown of hsa_circ_0096157 inhibits autophagy and DDP resistance in NSCLC cells by downregulating the Nrf2/ARE signaling pathway.

EHMT2-mediated transcriptional reprogramming drives neuroendocrine transformation in non-small cell lung cancer.

The transformation of lung adenocarcinoma to small cell lung cancer (SCLC) is a recognized resistance mechanism and a hindrance to therapies using epidermal growth factor receptor tyrosine kinase inhibitors (TKIs). The paucity of pretranslational/posttranslational clinical samples limits the deeper understanding of resistance mechanisms and the exploration of effective therapeutic strategies. Here, we developed preclinical neuroendocrine (NE) transformation models. Next, we identified a transcriptional reprogramming mechanism that drives resistance to erlotinib in NE transformation cell lines and cell-derived xenograft mice. We observed the enhanced expression of genes involved in the EHMT2 and WNT/ß-catenin pathways. In addition, we demonstrated that EHMT2 increases methylation of the SFRP1 promoter region to reduce SFRP1 expression, followed by activation of the WNT/ß-catenin pathway and TKI-mediated NE transformation. Notably, the similar expression alterations of EHMT2 and SFRP1 were observed in transformed SCLC samples obtained from clinical patients. Importantly, suppression of EHMT2 with selective inhibitors restored the sensitivity of NE transformation cell lines to erlotinib and delayed resistance in cell-derived xenograft mice. We identify a transcriptional reprogramming process in NE transformation and provide a potential therapeutic target for overcoming resistance to erlotinib.

Spatial interaction and functional status of CD68+SHP2+ macrophages in tumor microenvironment correlate with overall survival of NSCLC.

Background: Tumor-associated macrophages (TAMs) constitute a plastic and heterogeneous cell population of the tumor microenvironment (TME) that can regulate tumor proliferation and support resistance to therapy, constituting promising targets for the development of novel anticancer agents. Our previous results suggest that SHP2 plays a crucial role in reprogramming the phenotype of TAMs. Thus, we hypothesized that SHP2+ TAM may predict the treatment efficacy of non-small cell lung cancer NSCLC patients as a biomarker. Methods: We analyzed cancer tissue samples from 79 NSCLC patients using multiplex fluorescence (mIF) staining to visualize various SHP-2+ TAM subpopulations (CD68+SHP2+, CD68+CD86+, CD68 + 206+, CD68+ CD86+SHP2+, CD68+ CD206+SHP2+) and T cells (CD8+ Granzyme B +) of immune cells. The immune cells proportions were quantified in the tumor regions (Tumor) and stromal regions (Stroma), as well as in the overall tumor microenvironment (Tumor and Stroma, TME). The analysis endpoint was overall survival (OS), correlating them with levels of cell infiltration or effective density. Cox regression was used to evaluate the associations between immune cell subsets infiltration and OS. Correlations between different immune cell subsets were examined by Spearman's tests. Results: In NSCLC, the distribution of different macrophage subsets within the TME, tumor regions, and stroma regions exhibited inconsistency. The proportions of CD68+ SHP2+ TAMs (P < 0.05) were higher in tumor than in stroma. And the high infiltration of CD68+SHP2+ TAMs in tumor areas correlated with poor OS (P < 0.05). We found that the expression level of SHP2 was higher in M2-like macrophages than in M1-like macrophages. The CD68+SHP2+ subset proportion was positively correlated with the CD68+CD206+ subset within TME (P < 0.0001), tumor (P < 0.0001) and stroma (P < 0.0001). Conclusions: The high infiltration of CD68+SHP2+ TAMs predict poor OS in NSCLC. Targeting SHP2 is a potentially effective strategy to inhibit M2-phenotype polarization. And it provides a new thought for SHP2 targeted cancer immunotherapy.

Acetate reprogrammes tumour metabolism and promotes PD-L1 expression and immune evasion by upregulating c-Myc.

Acetate, a precursor of acetyl-CoA, is instrumental in energy production, lipid synthesis and protein acetylation. However, whether acetate reprogrammes tumour metabolism and plays a role in tumour immune evasion remains unclear. Here, we show that acetate is the most abundant short-chain fatty acid in human non-small cell lung cancer tissues, with increased tumour-enriched acetate uptake. Acetate-derived acetyl-CoA induces c-Myc acetylation, which is mediated by the moonlighting function of the metabolic enzyme dihydrolipoamide S-acetyltransferase. Acetylated c-Myc increases its stability and subsequent transcription of the genes encoding programmed death-ligand 1, glycolytic enzymes, monocarboxylate transporter 1 and cell cycle accelerators. Dietary acetate supplementation promotes tumour growth and inhibits CD8+ T cell infiltration, whereas disruption of acetate uptake inhibits immune evasion, which increases the efficacy of anti-PD-1-based therapy. These findings highlight a critical role of acetate promoting tumour growth beyond its metabolic role as a carbon source by reprogramming tumour metabolism and immune evasion, and underscore the potential of controlling acetate metabolism to curb tumour growth and improve the response to immune checkpoint blockade therapy.

Assessing personalized responses to anti-PD-1 treatment using patient-derived lung tumor-on-chip.

There is a compelling need for approaches to predict the efficacy of immunotherapy drugs. Tumor-on-chip technology exploits microfluidics to generate 3D cell co-cultures embedded in hydrogels that recapitulate simplified tumor ecosystems. Here, we present the development and validation of lung tumor-on-chip platforms to quickly and precisely measure ex vivo the effects of immune checkpoint inhibitors on T cell-mediated cancer cell death by exploiting the power of live imaging and advanced image analysis algorithms. The integration of autologous immunosuppressive FAP+ cancer-associated fibroblasts impaired the response to anti-PD-1, indicating that tumors-on-chips are capable of recapitulating stroma-dependent mechanisms of immunotherapy resistance. For a small cohort of non-small cell lung cancer patients, we generated personalized tumors-on-chips with their autologous primary cells isolated from fresh tumor samples, and we measured the responses to anti-PD-1 treatment. These results support the power of tumor-on-chip technology in immuno-oncology research and open a path to future clinical validations.

Adverse Event Profile of Atezolizumab, Bevacizumab, Carboplatin, and Paclitaxel Combination Therapy Based on JADER.

BACKGROUND/AIM: There have been advances in the development of immune checkpoint inhibitors for monotherapy and combination therapy with other anticancer agents in recent years. The combination of bevacizumab, carboplatin, and paclitaxel with atezolizumab, an anti-programmed death ligand 1 antibody (ABCP therapy), has been reported to be effective for treating non-small cell lung cancer. However, reports on its adverse events are limited. In this study, a survey and disproportionality analysis based on the Japanese Adverse Drug Event Report (JADER) database was conducted to elucidate the adverse event profile of ABCP therapy. MATERIALS AND METHODS: The reporting odds ratio (ROR) and information component were used as indicators for the disproportionality analysis. The ROR was also used to assess the changes in the reporting intensity with combination therapy, and the mutual exclusivity of the 95% confidence interval between the compared groups was considered. RESULTS: The reported adverse events of ABCP therapy mirrored those of the individual drugs that constituted it. ABCP therapy enhanced the reporting intensity of adverse events related to leukocytes and the skin, while decreased those related to interstitial lung disease and hepatic function abnormality as immune-related adverse events caused by atezolizumab, and gastrointestinal perforation caused by bevacizumab. CONCLUSION: Our analysis of data from the JADER database has revealed the adverse event profile of ABCP therapy. Our findings emphasize the importance of effectively managing febrile neutropenia and skin-related adverse events in ABCP therapy.

Deciphering the Role of miR-30a-5p and DLGAP1 Gene in Non-small Cell Lung Cancer.

BACKGROUND/AIM: Non-small cell lung cancer (NSCLC) is the deadliest form of cancer worldwide. Understanding the mechanisms of lung cancer development is vital for targeted therapy advancements. This article explores the little-known role of the guanylate kinase-associated protein (GKAP), encoded by the Disks large-associated protein 1 (DLGAP1) gene, in NSCLC along with assessing microRNA-30a-5p's influence on DLGAP1 gene expression in the A549 cell line. MATERIALS AND METHODS: Experiments were conducted on A549 cells transfected with synthetic oligonucleotides. The luciferase assay was employed to confirm the binding site of miR-30a-5p to the 3'UTR of DLGAP1 mRNA. The role of miRNA-30a-5p mimic in regulating potential target gene expression at the protein and mRNA levels was studied by performing RT-qPCR and western blot analyses. The effects of DLGAP1 knockdown and miRNA-30a-5p mimic on cell viability and the cell cycle were evaluated using the MTT test and flow cytometry with annexin/iodide cell staining. RESULTS: The luciferase assay indicated that miR-30a-5p has the ability to bind to the 3'UTR of DLGAP1 mRNA. RT-qPCR revealed that the overexpression of miR-30a-5p down-regulates DLGAP1 mRNA. Western blot analysis indicated that miR-30a-5p slightly reduces the level of the GKAP protein. Knockdown of DLGAP1 with synthetic oligonucleotides, as well as transfection with a miR-30a-5p mimic, significantly attenuates cell proliferation and increases the number of cells in the early and late stages of apoptosis. CONCLUSION: Our findings reveal the antiproliferative effect of miR-30a-5p and DLGAP1 gene knockdown on A549 cancer cells, implying that these elements could be considered as therapeutic targets for personalized medicine in NSCLC patients.

Effect of Epidermal Growth Factor Receptor Mutation on Positron Emission Tomography/Computed Tomography in Lung Cancer.

BACKGROUND/AIM: This study analyzed the effect of epidermal growth factor receptor (EGFR) mutations on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) results in lung cancer and the pathological findings in patients subjected to surgery. PATIENTS AND METHODS: A total of 210 patients diagnosed with lung cancer by F-18 FDG PET/CT at Inje University Busan Paik Hospital between January 2018 and December 2023 were recruited. EGFR mutation tests were performed on biopsy specimens. Overall, 78 patients (37.1%) with EGFR mutations were included in this study. Twenty-seven patients (12.9%) had distant metastases at the time of diagnosis. Of all patients, 69 (32.9%) underwent surgery at our hospital, and their pathological findings were analyzed. RESULTS: The maximum standardized uptake value (SUVmax) of F-18 FDG PET/CT was <10 in patients with EGFR mutations. Patients with EGFR mutations were not commonly diagnosed with diabetes. When analyzing the pathological findings after surgery in the 69 patients, adenocarcinoma was more common in those with EGFR mutations. In contrast, perineural invasion was more common in patients without EGFR mutations. When analyzing the results of 69 patients with postoperative pathology, 25 relapsed during the median follow-up of 21.7 months (range=0.9-58.4 months). Patients who underwent surgery and had EGFR mutations (n=26) exhibited lower recurrence rates compared to those without EGFR mutations. Disease-free survival was longer in patients with EGFR mutations. CONCLUSION: In non-small-cell lung cancer with an EGFR mutation, the F-18 FDG PET/CT SUVmax value and the probability of recurrence were lower. EGFR mutations are associated with low-glucose metabolism.

Current status and breakthroughs in treating advanced non-small cell lung cancer with EGFR exon 20 insertion mutations.

Recently, targeted therapy and immunotherapy have emerged as effective treatment options for non-small cell lung cancer (NSCLC). This progress has been facilitated by the rapid development of diagnostic and therapeutic technologies and the continuous research and development of new drugs, leading to a new era in precision medicine for NSCLC. This is a breakthrough for patients with common mutations in the human epidermal growth factor receptor (EGFR) gene in NSCLC. Consequently, the use of targeted drugs has significantly improved survival. Nevertheless, certain rare genetic mutations are referred to as EGFR exon 20 insertion (ex20ins) mutations, which differ in structure from conventional EGFR gene mutations, namely, exon 19 deletion mutations (19-Del) and exon 21 point mutations. Owing to their distinct structural characteristics, patients harboring these EGFR ex20ins mutations are unresponsive to traditional tyrosine kinase inhibitor (TKI) therapy. This particular group of patients did not fall within the scope of their applicability. However, the activating A763_Y764insFQEA mutation elicits a more pronounced response than mutations in the near and far regions of the C-helix immediately following it and should, therefore, be treated differently. Currently, there is a lack of effective treatments for EGFR ex20ins mutations NSCLC. The efficacy of chemotherapy has been relatively favorable, whereas the effectiveness of immunotherapy remains ambiguous owing to inadequate clinical data. In addition, the efficacy of the first- and second-generation targeted drugs remains limited. However, third-generation and novel targeted drugs have proven to be effective. Although novel EGFR-TKIs are expected to treat EGFR ex20ins mutations in patients with NSCLC, they face many challenges. The main focus of this review is on emerging therapies that target NSCLC with EGFR ex20ins and highlight major ongoing clinical trials while also providing an overview of the associated challenges and research advancements in this area.

Multidisciplinary meeting review in nonsmall cell lung cancer: a systematic review and meta-analysis.

BACKGROUND: Lung cancer diagnosis, staging and treatment may be enhanced by multidisciplinary participation and presentation in multidisciplinary meetings (MDM). We performed a systematic review and meta-analysis to explore literature evidence of clinical impacts of MDM exposure. METHODS: A study protocol was registered (PROSPERO identifier CRD42021258069). Randomised controlled trials and observational cohort studies including adults with nonsmall cell lung cancer and who underwent MDM review, compared to no MDM, were included. MEDLINE, CENTRAL, Embase and ClinicalTrials.gov were searched on 31 May 2021. Studies were screened and extracted by two reviewers. Outcomes included time to diagnosis and treatment, histological confirmation, receipt of treatments, clinical trial participation, survival and quality of life. Risk of bias was assessed using the ROBINS-I (Risk of Bias in Non-randomised Studies - of Interventions) tool. RESULTS: 2947 citations were identified, and 20 studies were included. MDM presentation significantly increased histological confirmation of diagnosis (OR 3.01, 95% CI 2.30-3.95; p<0.00001) and availability of clinical staging (OR 2.55, 95% CI 1.43-4.56; p=0.002). MDM presentation significantly increased likelihood of receipt of surgery (OR 2.01, 95% CI 1.29-3.12; p=0.002) and reduced the likelihood of receiving no active treatment (OR 0.32, 95% CI 0.21-0.50; p=0.01). MDM presentation was protective of both 1-year survival (OR 3.23, 95% CI 2.85-3.68; p<0.00001) and overall survival (hazard ratio 0.63, 95% CI 0.55-0.72; p<0.00001). DISCUSSION: MDM presentation was associated with increased likelihood of histological confirmation of diagnosis, documentation of clinical staging and receipt of surgery. Overall and 1-year survival was better in those presented to an MDM, although there was some clinical heterogeneity in participants and interventions delivered. Further research is required to determine the optimal method of MDM presentation, and address barriers to presentation.

SDF-1 promotes metastasis of NSCLC by enhancing chemoattraction of megakaryocytes through the PI3K/Akt signaling pathway.

Lung cancer (LC) is the leading cause of cancer-associated deaths worldwide, among which non-small-cell lung cancer (NSCLC) accounts for 80%. Stromal cell-derived factor-1 (SDF-1) inhibition results in a significant depletion of NSCLC metastasis. Additionally, SDF-1 is the only natural chemokine known to bind and activate the receptor CXCR4. Thus, we attempted to clarify the molecular mechanism of SDF-1 underlying NSCLC progression. Transwell migration, adhesion, and G-LISA assays were used to assess megakaryocytic chemotaxis in vitro and in vivo in terms of megakaryocytic migration, adherence, and RhoA activation, respectively. Western blotting was used to assess PI3K/Akt-associated protein abundances in MEG-01 cells and primary megakaryocytes under the indicated treatment. A hematology analyzer and flow cytometry were used to assess platelet counts in peripheral blood and newly formed platelet counts in Lewis LC mice under different treatments. Immunochemistry and flow cytometry were used to measure CD41+ megakaryocyte numbers in Lewis LC mouse tissue under different treatments. ELISA was used to measure serum TPO levels, and H&E staining was used to detect NSCLC metastasis.SDF-1 receptor knockdown suppressed megakaryocytic chemotaxis in Lewis LC mice. SDF-1 receptor inhibition suppressed megakaryocytic chemotaxis via the PI3K/Akt pathway. SDF-1 receptor knockdown suppressed CD41+ megakaryocyte numbers in vivo through PI3K/Akt signaling. SDF-1 receptor inhibition suppressed CD41+ megakaryocytes to hinder NSCLC metastasis. SDF-1 facilitates NSCLC metastasis by enhancing the chemoattraction of megakaryocytes via the PI3K/Akt signaling pathway, which may provide a potential new direction for seeking therapeutic plans for NSCLC.

The role of chemoradiotherapy and immunotherapy in stage III NSCLC.

Locally advanced non-small lung cancer encompasses a diverse range of tumors. In the last few years, the treatment of stage III unresectable non-small lung cancer has evolved significantly. The PACIFIC trial opened a new therapeutic era in the treatment of locally advanced NSCLC, establishing durvalumab consolidation therapy as the new standard of care worldwide. A careful evaluation of this type of lung cancer and a discussion of the management of these patients within a multidisciplinary team represents a crucial step in defining the best treatment strategy for each patient. For unresectable stage III NSCLC, definitive concurrent chemoradiotherapy (CCRT) was historically recommended as a treatment with a 5-year survival rate ranging from 20% to 30%. The PACIFIC study conducted in 2017 compared the use of chemoradiotherapy and maintenance therapy with the anti-PD-L1 monoclonal antibody durvalumab to a placebo in patients with locally advanced NSCLC who had not experienced disease progression. The study was prospective, randomized, and phase III. The administration of this medication in patients with locally advanced non-small cell lung cancer (NSCLC) has demonstrated a notable improvement in overall survival. Multiple clinical trials are currently exploring various immune checkpoint inhibition regimens to enhance the treatment efficacy in patients with stage III cancer. Our goal is to offer an up-to-date summary of the planned clinical trials for treatment options, focusing on the significant obstacles and prospects in the post-PACIFIC era.

Identifying the Multitarget Pharmacological Mechanism of Action of Genistein on Lung Cancer by Integrating Network Pharmacology and Molecular Dynamic Simulation.

Food supplements have become beneficial as adjuvant therapies for many chronic disorders, including cancer. Genistein, a natural isoflavone enriched in soybeans, has gained potential interest as an anticancer agent for various cancers, primarily by modulating apoptosis, the cell cycle, and angiogenesis and inhibiting metastasis. However, in lung cancer, the exact impact and mechanism of action of genistein still require clarification. To provide more insight into the mechanism of action of genistein, network pharmacology was employed to identify the key targets and their roles in lung cancer pathogenesis. Based on the degree score, the hub genes AKT1, CASP3, EGFR, STAT3, ESR1, SRC, PTGS2, MMP9, PRAG, and AR were significantly correlated with genistein treatment. AKT1, EGFR, and STAT3 were enriched in the non-small cell lung cancer (NSCLC) pathway according to Kyoto Encyclopedia of Genes and Genomes analysis, indicating a significant connection to lung cancer development. Moreover, the binding affinity of genistein to NSCLC target proteins was further verified by molecular docking and molecular dynamics simulations. Genistein exhibited potential binding to AKT1, which is involved in apoptosis, cell migration, and metastasis, thus holding promise for modulating AKT1 function. Therefore, this study aimed to investigate the mechanism of action of genistein and its therapeutic potential for the treatment of NSCLC.

Prognostic implications of STK11 with different mutation status and its relationship with tumor-infiltrating immune cells in non-small cell lung cancer.

Background: Mutations in STK11 (STK11Mut) gene may present a negative impact on survival in Non-small Cell Lung Cancer (NSCLC) patients, however, its relationship with immune related genes remains unclear. This study is to unveil whether overexpressed- and mutated-STK11 impact survival in NSCLC and to explore whether immune related genes (IRGs) are involved in STK11 mutations. Methods: 188 NSCLC patients with intact formalin-fixed paraffin-embedded (FFPE) tissue available for detecting STK11 protein expression were included in the analysis. After immunohistochemical detection of STK11 protein, patients were divided into high STK11 expression group (STK11High) and low STK11 expression group (STK11Low), and then Kaplan-Meier survival analysis and COX proportional hazards model were used to compare the overall survival (OS) and progression-free survival (PFS) of the two groups of patients. In addition, the mutation data from the TCGA database was used to categorize the NSCLC population, namely STK11 Mutated (STK11Mut) and wild-type (STK11Wt) subgroups. The difference in OS between STK11Mut and STK11Wt was compared. Finally, bioinformatics analysis was used to compare the differences in IRGs expression between STK11Mut and STK11Wt populations. Results: The median follow-up time was 51.0 months (range 3.0 - 120.0 months) for real-life cohort. At the end of follow-up, 64.36% (121/188) of patients experienced recurrence or metastasis. 64.89% (122/188) of patients ended up in cancer-related death. High expression of STK11 was a significant protective factor for NSCLC patients, both in terms of PFS [HR=0.42, 95% CI= (0.29-0.61), P<0.001] and OS [HR=0.36, 95% CI= (0.25, 0.53), P<0.001], which was consistent with the finding in TCGA cohorts [HR=0.76, 95%CI= (0.65, 0.88), P<0.001 HR=0.76, 95%CI= (0.65, 0.88), P<0.001]. In TCGA cohort, STK11 mutation was a significant risk factor for NSCLC in both lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD) histology in terms of OS [HR=6.81, 95%CI= (2.16, 21.53), P<0.001; HR=1.50, 95%CI= (1.00, 2.26), P=0.051, respectively]. Furthermore, 7 IRGs, namely CALCA, BMP6, S100P, THPO, CGA, PCSK1 and MUC5AC, were found significantly overexpressed in STK11-mutated NSCLC in both LUSC and LUAD histology. Conclusions: Low STK11 expression at protein level and presence of STK11 mutation were associated with poor prognosis in NSCLC, and mutated STK11 might probably alter the expression IRGs profiling.

Can hypoxia marker carbonic anhydrase IX serve as a potential new diagnostic marker and therapeutic target of non-small cell lung cancer?

Lung cancer represents the leading cause of cancer-related deaths. Non-small cell lung cancer (NSCLC), the most common form of lung cancer, is a molecularly heterogeneous disease with intratumoral heterogeneity and a significant mutational burden associated with clinical outcome. Tumor microenvironment (TME) plays a fundamental role in the initiation and progression of primary de novo lung cancer and significantly influences the response of tumor cells to therapy. Hypoxia, an integral part of the tumor microenvironment and a serious clinical phenomenon, is associated with increased genetic instability and a more aggressive phenotype of NSCLC, which correlates with the risk of metastasis. Low oxygen concentration influences all components of TME including the immune microenvironment. Hypoxia-inducible pathway activated in response to low oxygen supply mediates the expression of genes important for the adaptation of tumor cells to microenvironmental changes. A highly active transmembrane hypoxia-induced metalloenzyme - carbonic anhydrase IX (CAIX), as a part of transport metabolon, contributes to the maintenance of intracellular pH within physiological values and to the acidification of the extracellular space. CAIX supports cell migration and invasion and plays an important role in NSCLC tumor tissue and pleural effusion. Due to its high expression, it also represents a potential diagnostic differential biomarker and therapeutic target in NSCLC. To test new potential targeted therapeutic compounds, suitable models are required that more faithfully simulate tumor tissue, TME components, and spatial architecture.

Common immunological and prognostic features of lung and bladder cancer via smoking-related genes: PRR11 gene as potential immunotherapeutic target.

Smoking is a well-known risk factor for non-small-cell lung cancer (NSCLC) and bladder urothelial carcinoma (BLCA). Despite this, there has been no investigation into a prognostic marker based on smoking-related genes that could universally predict prognosis in these cancers and correlate with immune checkpoint therapy. This study aimed to identify smoking-related differential genes in NSCLC and BLCA, analyse their roles in patient prognosis and immune checkpoint therapy through subgroup analyses, and shed light on PRR11 as a crucial prognostic gene in both cancers. By examining PRR11 co-expressed genes, a prognostic model was constructed and its impact on immunotherapy for NSCLC and BLCA was evaluated. Molecular docking and tissue microarray analyses were conducted to explore the correlation between PRR11 and its reciprocal gene SPDL1. Additionally, miRNAs associated with PRR11 were analysed. The study confirmed a strong link between smoking-related genes, prognosis, and immune checkpoint therapy in NSCLC and BLCA. PRR11 was identified as a key smoking-associated gene that influences the efficacy of immune checkpoint therapy by modulating the stemness of these cancers. A prognostic model based on PRR11 co-expressed genes in BLCA was established and its prognostic value was validated in NSCLC. Furthermore, it was found that PRR11 regulates PDL1 via SPDL1, impacting immunotherapeutic efficacy in both cancers. The involvement of hsa-miR-200b-3p in the regulation of SPDL1 expression by PRR11 was also highlighted. Overall, the study elucidates that PRR11 modulates patient immunotherapy by influencing PDL1 expression through its interaction with SPDL1, with potential upstream regulation by hsa-miR-200b-3p.

Mitochondrial respiratory function is preserved under cysteine starvation via glutathione catabolism in NSCLC.

Cysteine metabolism occurs across cellular compartments to support diverse biological functions and prevent the induction of ferroptosis. Though the disruption of cytosolic cysteine metabolism is implicated in this form of cell death, it is unknown whether the substantial cysteine metabolism resident within the mitochondria is similarly pertinent to ferroptosis. Here, we show that despite the rapid depletion of intracellular cysteine upon loss of extracellular cystine, cysteine-dependent synthesis of Fe-S clusters persists in the mitochondria of lung cancer cells. This promotes a retention of respiratory function and a maintenance of the mitochondrial redox state. Under these limiting conditions, we find that glutathione catabolism by CHAC1 supports the mitochondrial cysteine pool to sustain the function of the Fe-S proteins critical to oxidative metabolism. We find that disrupting Fe-S cluster synthesis under cysteine restriction protects against the induction of ferroptosis, suggesting that the preservation of mitochondrial function is antagonistic to survival under starved conditions. Overall, our findings implicate mitochondrial cysteine metabolism in the induction of ferroptosis and reveal a mechanism of mitochondrial resilience in response to nutrient stress.