Cisplatin and photodynamic therapy exert synergistic inhibitory effects on small-cell lung cancer cell viability and xenograft tumor growth.

Lung cancer is the leading cause of cancer death worldwide. Small-cell lung cancer (SCLC) is an aggressive type of lung cancer that shows an overall 5-year survival rate below 10%. Although chemotherapy using cisplatin has been proven effective in SCLC treatment, conventional dose of cisplatin causes adverse side effects. Photodynamic therapy, a form of non-ionizing radiation therapy, is increasingly used alone or in combination with other therapeutics in cancer treatment. Herein, we aimed to address whether low dose cisplatin combination with PDT can effectively induce SCLC cell death by using in vitro cultured human SCLC NCI-H446 cells and in vivo tumor xenograft model. We found that both cisplatin and PDT showed dose-dependent cytotoxic effects in NCI-H446 cells. Importantly, co-treatment with low dose cisplatin (1 µM) and PDT (1.25 J/cm2) synergistically inhibited cell viability and cell migration. We further showed that the combined therapy induced a higher level of intracellular ROS in cultured NCI-H446 cells. Moreover, the synergistic effect by cisplatin and PDT was recapitulated in tumor xenograft as revealed by a more robust increase in the staining of TUNEL (a marker of cell death) and decrease in tumor volume. Taken together, our findings suggest that low dose cisplatin combination with PDT can be an effective therapeutic modality in the treatment of SCLC patients.

The roles of ARHGAP10 in the proliferation, migration and invasion of lung cancer cells.

Lung cancer is a leading cause of cancer-related mortalities worldwide. In the present study, a comparison of To determine the roles of ARHGAP10 in the proliferation, migration and invasion of lung cancer cells expression levels between normal lung tissues and lung cancer tissues were compared using immunoblotting, and CCK-8 and Transwell assays. Lung cancer tissues had a decreased ARHGAP10 mRNA expression level compared to the adjacent normal tissues. The ectopic expression of ARHGAP10 significantly suppressed the migration, invasion and proliferation of lung cancer cells. Gene set enrichment analysis revealed that metastasis and Wnt signaling pathways were negatively correlated with ARHGAP10 expression. Immunoblotting analysis revealed that ARHGAP10 overexpression inhibited metastasis [matrix metalloproteinase (MMP)-2, MMP-9 and VEGF] and the expression of Wnt pathway-related proteins (ß-catenin and c-Myc). Moreover, the stimulation effects of lithium chloride, a GSK3ß inhibitor, on the accumulation of ß-catenin were notably suppressed by ARHGAP10 overexpression. Collectively, ARHGAP10 acts to suppress tumor within lung cancer by affecting metastasis and Wnt signaling pathways. The results therefore suggest that ARHGAP10 is a potentially attractive target for the treatment of lung cancer.