ARID1A deficiency promotes progression and potentiates therapeutic antitumour immunity in hepatitis B virus-related hepatocellular carcinoma.

BACKGROUND: Exploring predictive biomarkers and therapeutic strategies of ICBs has become an urgent need in clinical practice. Increasing evidence has shown that ARID1A deficiency might play a critical role in sculpting tumor environments in various tumors and might be used as pan-cancer biomarkers for immunotherapy outcomes. The current study aims to explored the immune-modulating role of ARID1A deficiency in Hepatitis B virus (HBV) related hepatocellular carcinoma (HBV-HCC) and its potential immunotherapeutic implications. METHODS: In the current study, we performed a comprehensive analysis using bioinformatics approaches and pre-clinical experiments to evaluate the ARID1A regulatory role on the biological behavior, and immune landscape of Hepatitis B virus (HBV) related hepatocellular carcinoma (HBV-HCC). A total of 425 HBV-related hepatocellular carcinoma patients from TCGA-LIHC, AMC and CHCC-HBV cohort were enrolled in bioinformatics analysis. Immunohistochemical staining of HBV-HCC specimens and ARID1A deficiency cellular models were used to validate the results of the analysis. RESULTS: Our results have shown that ARID1A deficiency promoted tumor proliferation and metastasis. More importantly, ARID1A deficiency in HBV-HCC was associated with the higher TMB, elevated immune activity, and up-regulated expression of immune checkpoint proteins, especially TIM-3 in HBV-HCC. Further, the expression of Galectin-9, which is the ligand of TIM-3, was elevated in the ARID1A knockout HBV positive cell line. CONCLUSION: To conclude, we have shown that the ARID1A deficiency was correlated with more active immune signatures and higher expression of immune checkpoints in HBV-HCC. Additionally, the present study provides insights to explore the possibility of the predictive role of ARID1A in HBV-HCC patients responsive to immunotherapy.

Plasma EGFR mutation abundance affects clinical response to first-line EGFR-TKIs in patients with advanced non-small cell lung cancer.

BACKGROUND: Activated epidermal growth factor receptor (EGFR) mutation is the main pathogenic cause of non-small cell lung cancer (NSCLC) in Asia. However, the impact of plasma EGFR mutation abundance, especially of the ultra-low abundance of EGFR mutation detected by highly sensitive techniques on clinical outcomes of first-line EGFR tyrosine kinase inhibitors (TKIs) for advanced NSCLC patients remains unclear. METHODS: We qualitatively detected baseline EGFR status of NSCLC tissues using amplification-refractory mutation system and quantified the plasma abundance of EGFR mutations through next-generation sequencing (NGS). Every 8-12 weeks, we performed dynamic detection of plasma mutation abundance and imaging evaluation. We analyzed the association between plasma abundance of EGFR sensitizing mutations, tumor size, tumor shrinkage percentage, concomitant TP53 mutations, and clinical response to TKIs. RESULTS: This prospective study enrolled 135 patients with advanced NSCLC. The objective response rate (ORR) and disease control rate (DCR) for EGFR mutation-positive patients were 50.0% and 87.0%, respectively. When the cutoff value of plasma EGFR mutation abundance was 0.1%, the ORRs of TKI-treated patients were significantly different (60.0% for the >0.1% group vs. 21.4% for the ≤0.1% group, P=0.028). Median progression-free survival (PFS) was significantly longer for participants with a mutation abundance above 0.1% compared to those with a 0.01-0.1% abundance (log rank, P=0.0115). There was no significant association between plasma abundance of EGFR sensitizing mutations and tumor size, tumor shrinkage percentage, or concomitant TP53 mutations. Cox multivariate analysis demonstrated that plasma mutation abundance was an independent predictive factor for PFS [hazard ratio (HR) 2.41, 95% confidence interval (CI): 1.12-5.20; P=0.025]. We identified 11 participants with the acquired T790M resistance mutation according to serial dynamic plasma samples. CONCLUSIONS: Liquid biopsy screening based on highly sensitive NGS is reliable for detecting drug resistance and actionable somatic mutations. The plasma abundance of the EGFR driver mutation affected clinical response to EGFR-TKIs in advanced NSCLC patients; prolongation of PFS was also observed in patients with an ultra-low abundance of EGFR sensitizing mutations.

Apatinib suppresses the Proliferation and Apoptosis of Gastric Cancer Cells via the PI3K/Akt Signaling Pathway.

PURPOSE: To observe the mechanism of the effects of Apatinib on the proliferation and apoptosis of human gastric cancer (HGC-27) cells via the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway through in vitro cytology experiments. METHODS: The human gastric cancer HGC-27 cell line was taken as the research object, and LY294002, an inhibitor of the PI3K/Akt signaling pathway, as the positive control. The experimental methods are as follows: (1) The proliferation of HGC-27 cells inhibited by Apatinib and LY294002 was observed by 3-(4,5)-dimethylthiahiazo-(z-y1)-3,5-diphenytetrazoli- umromide (MTT) assay; (2) flow cytometry was adopted to detect the apoptosis of cells after they were treated with drugs and the positive control; (3) different effects of varying concentrations of Apatinib on apoptosis-related genes and proteins, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax) and cysteine-aspartic acid protease (Caspase) 9, were detected via fluorescence quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting (WB), and the effects of different concentrations of Apatinib on the protein expressions of PI3K, phosphorylated (p)-PI3K, Akt and p-Akt were detected by Western blotting. RESULTS: (1) MTT results showed that Apatinib could effectively inhibit the proliferation of HGC-27 cells in a dose-dependent manner. (2) Flow cytometry results manifested that Apatinib could induce the apoptosis of HGC-27 cells. (3) The results of qRT-PCR and Western blotting demonstrated that apatinib was capable of inducing the expression of the pro-apoptotic genes, Bax and Caspase 9, and inhibit the expression of the anti-apoptotic gene Bcl-2. The final results of Western blotting confirmed that Apatinib could decrease the protein expression levels of p-PI3K and p-Akt, thus inhibiting the phosphorylation of the PI3K/Akt pathway. CONCLUSIONS: The experiment proves that Apatinib can effectively suppress the proliferation and induce the apoptosis of human gastric cancer HGC-27 cells, the mechanism of which is related to the inhibition on phosphorylation of the PI3K/Akt signaling pathway.