It is well known that the aberrant expression of programmed death ligand 1 (PD-L1) on tumor cells impairs antitumor immunity. To date, in hepatocellular carcinoma (HCC), the relationship between PD-L1 expression and host-tumor immunity is not well defined. Here, the expression levels of PD-L1 and CD8(+) T cell infiltration were analyzed by immunohistochemistry (IHC) in formalin fixed paraffin embedded (FFPE) specimens from 167 HCC patients undergoing resection. A significant positive association was found between PD-L1 expression and the presence of CD8(+) T cell (p < 0.0001). Moreover, constitutive PD-L1 protein expression was not detected by western blot in HepG2, Hep3B, and 7402 HCC cancer cell lines; but co-cultured these cell lines with INFγ, a cytokine produced by activated CD8(+) T cells, remarkably upregulated PD-L1 expression. In fresh frozen HCC specimens, INFγ was found to be significantly correlated with PD-L1 and CD8(+) gene expression, as evaluated by quantitative reverse transcriptase polymerase chain reaction (RT-PCR). These findings indicate that increased PD-L1 level may represent an adaptive immune resistance mechanism exerted by tumor cells in response to endogenous antitumor activity. Both increased intratumoral PD-L1 and CD8(+) were significantly associated with superior DFS (CD8(+): p = 0.03; PD-L1: p = 0.023) and OS (CD8(+): p = 0.001 and PD-L1: p = 0.059), but PD-L1 expression was not independently prognostic. In conclusions, PD-L1 upregulation is mainly induced by activated CD8(+) cytotoxic T cells pre-existing in HCC milieu rather than be constitutively expressed by the tumor cells, and it is a favorable prognostic factor for HCC.

The relationship between vascular endothelial growth factor-C (VEGF-C)/vascular endothelial growth factor receptor 3 (VEGFR-3) expression and clinicopathologic features of the patients with non-small cell lung cancer (NSCLC) was investigated. The expression of VEGF-C and VEGFR-3 was assessed in 65 patients with NSCLC by immunohistochemistry. The significance of VEGF-C and VEGFR-3 expression was analyzed statistically. The results showed that VEGF-C and VEGFR-3 were highly expressed in cytoplasm and membrane in lung cancer tissues with the positive rate being 55.4 % and 52.3 % respectively, while there was no expression in the normal lung tissues. The expression of VEGF-C was significantly increased in adenocacinoma as compared to other types of NSCLC (P<0.05). The VEGFR-3 expression was closely related with lymph node metastasis (P<0.01) and TNM stage (P<0.05). There was a positive correlation between the VEGF-C and VEGFR-3 expression in NSCLC patients (r=0.658, P<0.01). It is suggested that VEGFR-3 plays an important role in the lymphatic metastasis of NSCLC. The interaction between VEGF-C and VEGFR-3 may be deeply involved in the mechanism of lung cancer metastasis.

Esophageal squamous cell carcinoma (ESCC) is the most prevalent type in esophageal cancers. Despite accumulating achievements in treatments of ESCC, patients still suffer from recurrence because of the treatment failures, one of the reasons for which is radioresistance. Therefore, it is a necessity to explore the molecular mechanism underlying ESCC radioresistance. Long intergenic noncoding RNA 473 (LINC00473) has been reported to be aberrantly expressed in several human malignancies. However, its biological function in radiosensitivity of ESCC remains to be fully understood. This study explored the role of LINC00473 in radiosensitivity of ESCC cells and whether LINC00473 acted as a competing endogenous RNA to realize its modulation on radioresistance. We found that LINC00473 was markedly upregulated in ESCC tissues and cell lines, and its expression was remarkably related to cellular response to irradiation. In addition, knockdown of LINC00473 could sensitize ESCC cells to radiation in vitro. As for the underlying mechanism, we uncovered that there was a mutual inhibition between LINC00473 and miR‐374a‐5p. Spindlin1 (SPIN1) was verified as a downstream target of miR‐374a‐5p, and LINC00473 upregulated SPIN1 expression through negatively modulating miR‐374a‐5p expression. Furthermore, we revealed that SPIN1 could aggravate the radioresistance of ESCC cells. Finally, overexpression of SPIN1 reversed the LINC00473 silencing‐enhanced radiosensitivity in ESCC cells. To sum up, we demonstrated that LINC00473 facilitated radioresistance by regulating the miR‐374a‐5p/SPIN1 axis in ESCC.

A consistent positive association between cigarette smoking and the human esophageal cancer has been confirmed all over the world. However, details in the association need to be more focused on and be identified. Recently, aberrantly expressed microRNAs (miRNAs) have been shown to be promising biomarkers for understanding the tumorigenesis of a wide array of human cancers, including the esophageal cancer, and the deregulation on the epithelial to mesenchymal transition (EMT) by miRNAs is involved in the tumorigenesis. In present study, we were going to identify the role of nicotine-induced miR-21 in the EMT of esophageal cells. We found that there was an overexpression of miR-21 in esophageal specimens, having an association with cigarette smoking, and the upregulation of miR-21 was also induced by nicotine in esophageal carcinoma cell line, EC9706. Moreover, the upregulated miR-21 by nicotine promoted EMT transforming growth factor beta (TGF-β) dependently. Thus, the present study reveals a novel oncogenic role of nicotine in human esophageal cancer.