Hypoxia differently regulates the proportion of ALDHhi cells in lung squamous carcinoma H520 and adenocarcinoma A549 cells via the Wnt/ß-catenin pathway.

BACKGROUND: Cancer stem cells (CSCs) are a specific subpopulation of cancer cells with the ability of self-renewal, infinite proliferation, multidifferentiation and tumorigenicity, and play critical roles in cancer progression and treatment resistance. CSCs are tightly regulated by the tumor microenvironment, such as hypoxia; however, how hypoxia regulates CSCs in non-small cell lung cancer (NSCLC) remains unclear. METHODS: The proportion of ALDHhi cells was examined using the Aldefluor assay. Tankyrase inhibitor XAV939 and siRNA were used to inhibit ß-catenin while pcDNA3-ß-catenin (S33Y) plasmid enhanced the expression of ß-catenin. Western blot was administered for protein detection. The mRNA expression was measured by quantitative real-time PCR. RESULTS: We found that hypoxia led to an increase in the proportion of ALDHhi cells in lung squamous carcinoma (LUSC) H520 cells, while causing a decrease in the ALDHhi cell proportion in lung adenocarcinoma (LUAD) A549 cells. Similarly, ß-catenin expression was upregulated in H520 cells but downregulated in A549 cells upon exposure to hypoxia. Mechanically, the proportion of ALDHhi cells in both cell lines was decreased by ß-catenin inhibitor or siRNA knockdown, whereas increased after ß-catenin overexpression. Furthermore, hypoxia treatment suppressed E-cadherin expression in H520 cells and enhanced N-cadherin and ß-catenin expression, while this effect was completely opposite in A549 cells. CONCLUSION: The hypoxia-EMT-ß-catenin axis functions as an important regulator for the proportion of CSCs in NSCLC and could potentially be explored as therapeutic targets in the future.

Efficacy of immune checkpoint inhibitors in non-small cell lung cancer with NTRK family mutations.

BACKGROUND: The efficacy of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) patients harboring neurotrophin receptor kinase (NTRK) family mutations remains obscure. METHODS: The Zehir cohort from cBioPortal was used to analyze the mutations (MT) frequency of NTRK family in patients with NSCLC, and their correlation with clinical characteristics and patient survival. The influence of NTRK MT on ICIs efficacy was evaluated in ICIs-treated patients from Samstein cohort and further validated by use of data from OAK/POPLAR cohort. RESULTS: In the Zehir cohort, a significant difference was observed in median overall survival (mOS) between patients with NTRK MT and wild-type (WT) (mOS: 18.97 vs. 21.27 months, HR = 1.34, 95%CI 1.00-1.78; log-rank P = 0.047). In Samstein cohort, the mOS of NTRK mutant patients receiving ICIs has improved compared to WT patients (mOS: 21.00 vs. 11.00 months, log-rank P = 0.103). Notably, in subgroup analysis, ICIs significantly prolonged mOS in patients with NTRK3 MT than in WT patients (mOS: not available vs. 11.00 months, HR = 0.36, 95%CI 0.16-0.81; log-rank P = 0.009). Identical mOS between NTRK MT and WT patients receiving ICIs treatment (mOS: 13.24 vs. 13.50 months, log-rank P = 0.775) was observed in OAK/POPLAR cohort. Moreover, a similar programmed death ligand 1 (PD-L1) expression, but higher tumor mutational burden (TMB), blood TMB (bTMB) and enriched anti-tumor immunity were observed in NTRK MT compared to WT (P < 0.05). CONCLUSION: Taking high TMB or bTMB into consideration, patients with NTRK mutant NSCLC could benefit from ICIs treatment.

Predictive value of the prognostic nutritional index in advanced non-small cell lung cancer patients treated with immune checkpoint inhibitors: A systematic review and meta-analysis.

Purpose: The prognostic nutritional index (PNI), which is derived from the albumin concentration and absolute lymphocyte number, is an effective indicator of cancer patients' nutritional and immunological status. According to multiple studies, PNI was strongly linked to the prognosis of patients with non-small cell lung cancer (NSCLC). The predictive value of PNI for survival outcomes in NSCLC patients receiving immune checkpoint inhibitors (ICIs) is still in dispute at present. This meta-analysis is devoted to fill this information gap and investigate the predictive ability of PNI in NSCLC patients treated with ICIs. Methods: The PubMed, Embase, Cochrane Library databases, and conference proceedings were searched for eligible studies without language restriction. Overall survival (OS) and progression-free survival (PFS) were included. The predictive value of PNI was estimated using hazard ratios and their 95% confidence intervals. Results: Thirteen relevant retrospective cohort studies were included and these studies included 1119 patients with stage III-IV NSCLC. Lower PNI status was found to be an independent risk factor for worse survival outcomes in patients with NSCLC (OS HR = 2.68; 95%CI: 1.76-4.06; P < 0.0001; PFS HR = 1.84; 95%CI: 1.39-2.42; P < 0.0001). According to the subgroup analysis, PNI was similarly connected to OS in most subgroups of NSCLC patients receiving ICIs, except for those receiving chemoimmunotherapy or first-line treatment, and those with a cut-off value < 45. Conclusion: Our findings indicated that lower PNI was associated with poorer prognosis in NSCLC patients undergoing ICI therapy. Further prospective research with bigger patient groups is required. Systematic Review Registration: International Prospective Register of Systematic Reviews (PROSPERO), identifier CRD42022327528.

ANK2 as a novel predictive biomarker for immune checkpoint inhibitors and its correlation with antitumor immunity in lung adenocarcinoma.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have been shown to significantly improve the survival of patients with advanced lung adenocarcinoma (LUAD). However, only limited proportion of patients could benefit from ICIs. Novel biomarkers with strong predictability are needed for clinicians to maximize the efficacy of ICIs. Our study aimed to identify potential biomarkers predicting ICIs efficacy in LUAD. METHODS: The Cancer Genome Atlas (TCGA) PanCancer Atlas studies in cBioportal were used to evaluate the mutation frequency of ANK2 across multiple cancers. Clinical and mutational data for LUAD from ICIs-treated cohorts (Hellmann et al. and Rizvi et al.) were collected to explore the correlation between ANK2 mutation and clinical outcomes. In addition, the relationship between ANK2 expression and clinical outcomes was analyzed using LUAD data from TCGA and Gene Expression Omnibus. Furthermore, the impact of ANK2 mutation and expression on the tumor immune microenvironment of LUAD was analyzed using TCGA and TISIDB databases. RESULTS: Patients with ANK2 mutation benefited more from ICIs. In ICIs-treated cohort, prolonged progression-free survival (PFS) (median PFS: NR (not reached) vs. 5.42 months, HR (hazard ratio) 0.31, 95% CI 0.18-0.54; P = 0.0037), improved complete response rate (17.65% vs. 1.85%, P = 0.0402), and improved objective response rate (64.71% vs. 24.07%, P = 0.0033) were observed in LUAD patients with ANK2 mutation compared to their wild-type counterparts. Regarding ANK2 expression, it was observed that ANK2 expression was decreased in LUAD (P < 0.05) and a higher level of ANK2 expression was associated with longer overall survival (HR 0.69, 95% CI 0.52-0.92; P = 0.012) in TCGA LUAD cohort. Moreover, ANK2 mutation or higher ANK2 expression correlated with enhanced antitumor immunity and "hot" tumor microenvironment in LUAD, which could be potential mechanisms that ANK2 mutation facilitated ICIs therapy and patients with higher ANK2 expression survived longer. CONCLUSION: Our findings suggest that ANK2 mutation or increased ANK2 expression may serve as a favorable biomarker for the efficacy of ICIs in patients with LUAD.

Liver metastases and the efficacy of immune checkpoint inhibitors in advanced lung cancer: A systematic review and meta-analysis.

Background: Liver metastasis is the most common type of lung cancer metastasis, and is a significant prognostic factor in lung cancer. However, the effect of liver metastases on the efficacy of immune checkpoint inhibitors (ICIs) remains inconsistent and controversial. The aim of this study was to explore the relationship between liver metastases and ICI efficacy in patients with advanced lung cancer based on data from randomized controlled trials (RCTs) and observational studies. Methods: PubMed, EMBASE, Cochrane Library databases, conference proceedings, as well as grey literature websites were searched for eligible studies without language restrict ion. Study quality was assessed using Cochrane tools and the Newcastle-Ottawa Quality Assessment Scale (NOS). Outcomes of interest were overall survival (OS) and progression-free survival (PFS). The difference in efficacy between patients with and without liver metastases was calculated by pooling ratios of hazard ratios (HR), as calculated using the deft approach. Results: A total of 16 RCTs and 14 observational trials were included. Analyses of RCTs revealed a survival benefit for ICI treatment (i.e., ICI monotherapy, ICI + Chemotherapy, dual ICI therapy and dual ICI + Chemotherapy) versus standard therapies among non-small cell lung cancer (NSCLC) patients with liver metastases (PFS HR, 0.77; 95%CI, 0.61-0.97; OS HR, 0.78; 95%CI, 0.68-0.90). NSCLC patients with liver metastases achieved less PFS benefit and comparable OS benefit from ICI treatment compared with those without liver metastases (ratios of PFS-HRs, 1.19; 95%CI, 1.02-1.39; P=0.029; Ratios of OS-HRs, 1.10; 95%CI, 0.94-1.29; P=0.24). For patients with small cell lung cancer (SCLC), ICI treatment achieved a marginal effect on patients with liver metastases as compared with standard therapies (OS HR, 0.94; 95%CI, 0.73-1.23). SCLC patients with liver metastases benefited less from ICI treatment than patients without liver metastases (ratio of OS-HRs, 1.22; 95%CI, 1.01-1.46; P=0.036). In real-world data analysis, liver metastasis could be used as an independent prognostic risk factor, increasing the risk of death by 21% in lung cancer patients receiving ICI treatment compared with those without liver metastases (OS HR, 1.21; 95%CI, 1.17-1.27; P<0.0001). Subgroup analysis confirmed that this association was not modified by race (Asian vs. Western) or number of treatment lines. Conclusions: The presence of liver metastases does not significantly influence the OS benefit of ICIs in patients with NSCLC. However, a small amount of data shows that liver metastasis restrains the magnitude of OS benefit in patients with SCLC. Liver metastasis has potential as an independent prognostic risk factor for lung cancer patients receiving ICI treatment in clinical practice. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier (CRD42022306449).

Fibroblast growth factor receptor family mutations as a predictive biomarker for immune checkpoint inhibitors and its correlation with tumor immune microenvironment in melanoma.

Background: The emergence of immune checkpoint inhibitors (ICIs) has significantly improved the clinical outcomes of patients with metastatic melanoma. However, survival benefits are only observed in a subset of patients. The fibroblast growth factor receptor (FGFR) family genes are frequently mutated in melanoma, yet their impacts on the efficacy of ICIs remain unclear. Our study aimed to explore the association of FGFR mutations with ICIs efficacy in metastatic melanoma. Methods: The Cancer Genome Atlas (TCGA) data (PanCancer Atlas, skin cutaneous melanoma (SKCM), n = 448) in cBioPortal were collected as a TCGA cohort to investigate the association between FGFR mutations and prognosis of melanoma patients. To explore the impact of FGFR mutations on the efficacy of ICIs in melanoma, clinical and tumor whole-exome sequencing (WES) data of four ICI-treated studies from cBioPortal were consolidated as an ICIs-treated cohort. Moreover, the relationship between FGFR mutations and immunogenicity (tumor mutation burden (TMB), neo-antigen load (NAL), mismatch repair (MMR)-related genes and DNA damage repair (DDR)-related genes) of melanoma was evaluated utilizing data from the ICIs-treated cohort. The influence of FGFR mutations on the tumor immune microenvironment (TIME) of melanoma was also analyzed using the TCGA cohort. Results: In the TCGA cohort, survival in melanoma patients with or without FGFR mutations was nearly equivalent. In the ICIs-treated cohort, patients with FGFR mutations had better survival than those without (median overall survival: 60.00 vs. 31.00 months; hazard ratio: 0.58, 95% CI: 0.42-0.80; P = 0.0051). Besides, the objective response rate was higher for patients harboring FGFR mutations (55.56%) compared to wild-type patients (22.40%) (P = 0.0076). Mechanistically, it was revealed that FGFR mutations correlated with increased immunogenicity (e.g., TMB, NAL, MMR-related gene mutations and DDR-related gene mutations). Meanwhile, FGFR mutant melanoma tended to exhibit an enhanced antitumor TIME compared with its wild-type counterparts. Conclusions: Our study demonstrated that FGFR mutations is a promising biomarker in stratifying patients with advanced melanoma who might benefit from ICIs therapy.

CDC25C as a Predictive Biomarker for Immune Checkpoint Inhibitors in Patients With Lung Adenocarcinoma.

The application of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer has significantly improved patient survival. However, most patients fail to respond to ICIs or develop drug resistance during treatment. Therefore, novel biomarkers are needed to predict the efficacy of ICIs or provide clues on how to overcome drug resistance. Here, it was revealed that cell division cycle 25C (CDC25C) expression was upregulated in lung adenocarcinoma (LUAD) compared to that of normal lung tissue in multiple databases. This was further verified by q-PCR. Furthermore, higher CDC25C expression was associated with shorter overall survival and worse pathological stage. Most importantly, a higher CDC25C expression was associated with shorter progression-free survival in LUAD patients treated with nivolumab, suggesting the role of the cell cycle in immunotherapy. In addition, CDC25C expression was significantly associated with immune cell infiltration and immune-related signatures in the LUAD tumor microenvironment. Moreover, CDC25C was differentially expressed and correlated with overall survival in multiple tumors, indicating that CDC25C is a broad-spectrum biomarker. Taken together, our study demonstrates that CDC25C is a prognostic biomarker for LUAD patients, especially for patients treated with ICIs. Our study also provides strong evidence for the role of the cell cycle in ICIs therapy and tumor microenvironment.

Targeted paclitaxel-octreotide conjugates inhibited the growth of paclitaxel-resistant human non-small cell lung cancer A549 cells in vitro.

The application of chemotherapy in non-small cell lung cancer (NSCLC) is limited by the toxicity to normal cells and the development of multi-drug resistance. Targeted chemotherapy using cytotoxic analogs against specific receptors on cancer cells could be a less toxic and more efficacious approach. We identified that the expressions of somatostatin receptor (SSTR) 2 and 5 in tumor tissues from NSCLC patients were higher than those in the adjacent normal tissues by immunohistochemistry, and therefore, cytotoxic somatostatin analogues might be applied for SSTRs-mediated targeted therapy against NSCLC. Two cytotoxic analogs, paclitaxel-octreotide (PTX-OCT) and 2paclitaxel-octreotide (2PTX-OCT), were synthesized by linking one or two molecules of paclitaxel to one molecule of somatostatin analog octreotide. PTX-OCT and 2PTX-OCT significantly inhibited the growth and induced apoptosis of SSTR2- and SSTR5-positive A549 cells, compared with the control (p < 0.01), and had less inhibitory effect on SSTR2- and SSTR5-negative H157 cells than paclitaxel (p < 0.01). Moreover, compared with paclitaxel, PTX-OCT conjugates induced lower expression of MDR-1 gene both in vitro and in vivo. Three A549 paclitaxel-resistant cell lines were established through different approaches, and the paclitaxel-resistant cell showed higher sensitivity to PTX-OCT conjugates than to paclitaxel, which might be because of the differential MDR-related gene expressions and cell-cycle distribution in paclitaxel-resistant A549 cells. Our results suggested that PTX-OCT conjugates could be potentially used for SSTRs-mediated targeted therapy for NSCLC, especially for those with paclitaxel resistance and induced less multidrug resistance.