Valproic acid (VPA) enhances cisplatin sensitivity of non-small cell lung cancer cells via HDAC2 mediated down regulation of ABCA1.

Valproic acid (VPA) has been suggested to be a histone deacetylase inhibitor (HDACI). Our present study revealed that VPA at 1 mm, which had no effect on cell proliferation, can significantly increase the sensitivity of non-small cell lung cancer (NSCLC) cells to cisplatin (DDP). VPA treatment markedly decreased the mRNA and protein levels of ABCA1, while had no significant effect on ABCA3, ABCA7 or ABCB10. Luciferase reporter assays showed that VPA can decrease the ABCA1 promoter activity in both A549 and H358 cells. VPA treatment also decreased the phosphorylation of SP1, which can bind to -100 and -166 bp in the promoter of ABCA1. While the phosphorylation of c-Fos and c-Jun were not changed in VPA treated NSCLC cells. Over expression of HDAC2 attenuated VPA induced down regulation of ABCA1 mRNA expression and promoter activities. Over expression of HDAC2 also attenuated VPA induced DDP sensitivity of NSCLC cells. These data revealed that VPA can increase the DDP sensitivity of NSCLC cells via down regulation of ABCA1 through HDAC2/SP1 signals. It suggested that combination of VPA and anticancer drugs such as DDP might be great helpful for treatment of NSCLC patients.

Comprehensive analysis of Epha10 as a predictor of clinical prognosis and immune checkpoint therapy efficacy in non-small cell lung cancer.

The EphA family belongs to a large group of membrane receptor tyrosine kinases. Emerging evidence indicates that the EphA family participates in tumour occurrence and progression. Nonetheless, the expression patterns and prognostic values of the nine EphAs in non-small cell lung cancer (NSCLC) have rarely been studied before. In the current study, we comprehensively analysed the expression and prognostic role of EphA family members by different means. The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis databases were used to investigate the expression of EphAs in NSCLC. The cBioPortal database was applied to analyse the prognostic values and genetic mutations of EphAs.We discovered that the expression of EphA10 was significantly higher in NSCLC tissues than in adjacent noncancerous tissues, and survival analyses showed that a higher level of EphA10 predicted poor prognosis. Further exploration into the role of EphA10 by ESTIMATE, CIBERSORT, and ssGSEA analysis found that it was also related to immune infiltration and higher expression of targets of ICI targets. In conclusion, this study revealed that among the EphA family members, EphA10 played an oncogenic role and was a promising biomarker for poor prognosis and better immunotherapy response in NSCLC.

[Effect of Akt on the function of esophageal squamous cancer cell Eca109 and the expression of vasculogenic mimicry-related genes].

OBJECTIVE: To investigate the inhibitory effect of siRNA targeting Akt on the biological behavior of esophagus squamous cell carcinoma cell line in vitro and to explore the relationship between Akt and vasculogenic mimicry (VM)-related genes in esophageal squamous cell carcinoma. METHODS: The plasmid-harboring small interfering RNA targeting Akt was introduced into Eca109 cells by liposome-mediated transfection. The proliferation of Eca109 cell was determined by colony formation assay. The cellular migration was evaluated by Transwell migration assay. And three dimensional cell culture was employed to observe and count the number of capillary structure for each cell group. Flow cytometry (FCM) was used to detect the apoptotic rate of Eca109, Eca109/Neo and Eca109/siRNA Akt cells under normoxia exposure. The apoptotic rate was assessed by Annexin V/7-AAD double labeling. And the expressions of Akt and matrix metalloproteinase-2 (MMP-2) protein were detected by Western blotting. RESULTS: The results of Western blotting showed that the expression of Akt in stably transfected group were significantly lower than empty carrier and untransfected groups (0.03 ± 0.01 vs 1.49 ± 0.39 and 1.47 ± 0.41, both P < 0.05). Transwell migration assay showed that fewer Eca109/8 cells could move through the artificial basement membrane as compared with untransfected and empty carrier groups (48 ± 9 vs 128 ± 10 and 122 ± 11, both P < 0.05). Clone formation number of stably transfected group was significantly lower than empty carrier and untransfected groups (63 ± 7 vs 148 ± 11 and 163 ± 15, both P < 0.05). Annexin V/7-AAD double standard method demonstrated that the apoptotic rate of stably transfected group was much more than those of untransfected and empty carrier groups (12.2% ± 1.6% vs 4.8% ± 0.8% and 4.2% ± 0.8%, both P < 0.05). Eca109 and Eca109/Neo cells were capable of forming the in vitro structures of VM. And the number of tube-shaped structure in stably transfected group was markedly less than those of untransfected and empty carrier groups (14.0 ± 1.2 vs 30.0 ± 1.2 and 27.7 ± 1.5, both P < 0.05). MMP-2 protein expression in stably transfected group was less than those of untransfected and empty carrier groups (both P < 0.05). CONCLUSIONS: The PI(3)K/Akt pathway is involved in the regulation of VM formation in esophageal squamous cell carcinoma through the action of MMP-2. Blockade of this pathway may provide a new therapeutic approach to human esophagus squamous cell carcinoma.

MiR-484 promotes non-small-cell lung cancer (NSCLC) progression through inhibiting Apaf-1 associated with the suppression of apoptosis.

Increasing studies have indicated that the dysregulated microRNAs (miRNAs) are associated with tumorigenesis, development and even the poor prognosis of a variety of tumors, including the non-small-cell lung cancer (NSCLC). Here in our study, we found that miRNA-484 was expressed highly in NSCLC clinical tumor samples in comparison to the matched adjacent tissues. In addition, high and low expression of miRNA-484 was observed in NSCLC cell lines and lung normal cells, respectively. Furthermore, the capability of migration and proliferation changed accompanied with the altered expression of miR-484 in NSCLC. Apoptotic protease activating factor-1 (APAF-1), frequently down-regulated in a number of types of cancer, was found to be reduced in NSCLC tissue samples or NSCLC cell lines along with high expression of miR-484, which were inversely expressed in Apaf-1 over-expressed tissues or cells. Moreover, miR-484 triggered the migration and proliferation, and simultaneously reduced the cleavage of poly (ADP-ribose) polymerase-2 (PARP-2) and Caspase-3 of A549 cells, which could be suppressed by the improvement of Apaf-1. And the inhibition of Apaf-1 could reverse the function caused by miR-484 in A549 cells, suggesting that Apaf-1 was targeted by miR-484 directly and it could be acted as a potential therapeutic target against NSCLC. In conclusion, the reductive Apaf-1 regulated by miR-484 accelerated the NSCLC cell progression associated with the inhibition of apoptosis via down-regulating Caspase-3 and PARP cleavage.