Opportunities and Challenges of Kava in Lung Cancer Prevention

Combination of the cuproptosis inducer disulfiram and anti‑PD‑L1 abolishes NSCLC resistance by ATP7B to regulate the HIF‑1 signaling pathway

Disulfiram (DSF) is used to treat non‑small cell lung cancer (NSCLC). DSF significantly increases expression of programmed death‑ligand 1 (PD‑L1), which may enhance immunosuppression and immune escape of tumors. Therefore, the present study aimed to investigate the role of combined treatment of DSF and anti‑PD‑L1 in NSCLC resistance. The viability and apoptosis of A549 cells were detected by the Cell Counting Kit‑8 assay and flow cytometry, respectively. The expression levels of ATPase copper‑transporting β (ATP7B) and PD‑L1 in A549 cells were detected by reverse transcription‑quantitative PCR and western blot analysis. The levels of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) in A549 cells were detected by respective assay kits. The expression levels of cuproptosis‑associated proteins ferredoxin‑1 (FDX1), ATP7B, solute carrier family 31 member 1 (SLC31A1), succinate dehydrogenase B (SDHB), PD‑L1 and hypoxia inducible factor (HIF)‑1A were analyzed by western blotting in A549 cells. DSF inhibited the viability of A549 cells and promoted expression levels of ATP7B and PD‑L1 at both mRNA and protein levels in A549 cells. The viability of cisplatin (DPP)‑treated A549 cells was increased following DSF treatment. JQ‑1 (a PD‑L1 inhibitor) suppressed the viability of DPP‑treated A549 cells pretreated with DSF. DSF increased expression levels of ATP7B and PD‑L1. The combination treatment of DSF and JQ‑1 in A549 cells increased levels of ROS and MDA, as well as expression levels of FDX1 and SLC31A1; however, combination treatment decreased levels of SOD, as well as expression levels of ATP7B, SDHB, PD‑L1, and HIF‑1A. PX478 (an HIF‑1 inhibitor) acted with DSF to enhance the inhibitory effects on the viability and on the induction of apoptosis of A549 cells. PX478 upregulated the levels of ROS and MDA, while it downregulated levels of SOD in DSF‑treated A549 cells. PX478 promoted expression levels of FDX1 and SLC31A1, while it suppressed expression levels of ATP7B, PD‑L1, and HIF‑1A in DSF‑treated A549 cells. In conclusion, the combined treatment of A549 cells with anti‑PD‑L1 and DSF enhanced the effect of cuproptosis on the inhibition of NSCLC cell viability.

Clinicopathological characteristics correlated with programmed cell death-ligand 1 expression in advanced lung adenocarcinoma

Background

Recent studies have shown that immune checkpoint inhibitors (ICIs) targeting programmed cell death-ligand 1 (PD-L1) have potential benefits in patients with non-small cell lung cancer (NSCLC) subgroups, while the clinicopathological characteristics associated with PD-L1 expression have not been well established. The purpose of this study was to detect the expression level of PD-L1 in tumor tissues of patients with advanced lung adenocarcinoma (ADC) and analyze its possible relationship with clinicopathological characteristics, so as to identify the predictors of PD-L1 expression.

Methods

This retrospective study was conducted by analyzing the clinicopathological and imaging characteristics of hospitalized advanced lung ADC patients with PD-L1 available data and admitted to the respiratory department of our hospital. The expression level of PD-L1 in fresh-frozen tumor tissue samples of 136 advanced ADC patients was analyzed by immunohistochemistry. The patients were divided into positive and negative groups based on a cut-off of 1% PD-L1 expression level. Subsequently, the significant correlation between PD-L1 levels and clinicopathological features were evaluated. The predictive performance of clinicopathological characteristics on PD-L1 expression was evaluated and the optimal cut-off values were identified by plotting the receiver operating characteristic (ROC) curve.

Results

The expression level of PD-L1 was related to sex, clinical stage, serum carcinoembryonic antigen (CEA), neuron specific enolase (NSE), white blood cell (WBC), and tumor (T) and metastasis (M) stage. Multivariate logistic regression analysis showed the CEA, NSE, T stage, and WBC were independent predictors of PD-L1 positive expression in lung ADC patients. The ROC curve suggested the model combining CEA with NSE [area under the curve (AUC) =0.815] could better predict the expression levels of PD-L1. The optimal cut-off values for identifying advanced lung ADC patients with PD-L1 positive were CEA ≤13.38 ng/mL and NSE ≤42.35 ng/mL, with sensitivity and specificity of 85.4% and 55.6%, and 92.7% and 32.1%, respectively.

Conclusions

Some commonly used clinicopathological features are related to the histological expression of PD-L1. The serum CEA, NSE, T stage, and WBC values can be used as indicators to predict the expression level of PD-L1 in advanced lung ADC, and are used as predictors to evaluate the efficacy of ICIs before treatment.