Background HBV promotes cell survival by upregulating the expression of the cellular inhibitor of apoptosis protein 2 (cIAP2), however whether it is involved in HBV-induced sorafenib resistance in liver cancer remains unclear. Methods cIAP2 overexpression and knockdown was adopted to assess the involvement of cIAP2 in HBV-induced sorafenib resistance. Anti-HBV drug lamivudine and Akt inhibitor were used to investigate the impact of HBV replication on cIAP2 expression and sorafenib resistance. Xenotransplantation mouse model was used to confirm the data on cell lines in vitro. Results Liver cancer cell line HepG2.215 showed increased cIAP2 expression and enhanced resistance to sorafenib. Upon sorafenib treatment, overexpression of cIAP2 in HepG2 lead to decreased cleaved caspase 3 level and increased cell viability, while knockdown of cIAP2 in HepG2.215 resulted in increased level of cleaved caspase 3 and decreased cell viability, suggesting the involvement of cIAP2 in HBV-induced sorafenib resistance. Furthermore, anti-HBV treatment reduced cIAP2 expression and partially restored sorafenib sensitivity in HepG2.215 cells. Xenotransplantation mouse model further confirmed that co-treatment with lamivudine and sorafenib could reduce sorafenib-resistant HepG2.215 tumor cell growth. Conclusion cIAP2 is involved in HBV-induced sorafenib resistance in liver cancer and anti-HBV treatments reduce cIAP2 expression and partially restore sorafenib sensibility.

Objective: Serum uric acid is associated with tumor progression and hepatocarcinogenesis. Here, we aimed to determine whether serum uric acid is related to the survival time of patients with hepatocellular carcinoma (HCC) and whether the inhibition of uric acid production affects the progression and survival of rats with HCC. Methods: The follow-up data of 288 patients with advanced HCC were analyzed. Ten purine metabolites in serum and liver samples of diethylnitrosamine (DEN)-induced HCC rats were quantitatively determined by an established UPLC-MS/MS method. On this basis, febuxostat, a specific inhibitor of xanthine oxidase (XOD), was used to interfere with HCC rats. Results: The serum uric acid level of HCC patients was significantly negatively correlated with survival days (r = -0.155). The median survival time was 133.5 days in the high uric acid group (>360 μmol/L, n = 80) and 176.0 days in the normal serum uric acid group (<360 μmol/L, n = 208, p = 0.0013). The levels of hypoxanthine, guanine, and uric acid; XOD activity; and xanthine dehydrogenase mRNA expression in the serum or liver samples of HCC rats were significantly upregulated compared with those in the control group. After febuxostat intervention in DEN-induced HCC rats, the number of atypical cells and inflammatory cells decreased significantly; the serum alpha fetoprotein level and Fisher's ratio tended to return to normal; the median survival time increased from 36 to 96 days (p = 0.08). In addition, serum malondialdehyde, superoxide dismutase, and glutathione activity nearly returned to the level of the healthy control group. Conclusion: The elevation of serum uric acid implies a risk of poor survival in advanced HCC patients and Febuxostat can reduce the generation of reactive oxygen species, thereby playing a role in delaying the progression of liver cancer.

FZD8, a G protein-coupled receptor protein belonging to the Frizzled family, is considered to play an important role in cancer invasion and metastasis. However, the function of FZD8 in the invasion and metastasis of gastric cancer (GC) has not been elucidated. In this study, we first confirm that FZD8 protein expression was significantly upregulated in gastric cancer tissue and has a potential to be an independent predictor of poor prognosis for patients with GC. In vivo and in vitro evidences were provided that support the idea of FZD8 being able to suppress GC cell invasion and metastasis. Further studies show that FZD8 promotes the markers expression related to invasion and metastasis. FZD8 exerts biological function through the β-catenin pathway which plays an important role in invasion and metastasis of gastric cancer cells. Finally, FZD8 could activate the β-catenin pathway and its target gene's expression. In conclusion, our findings show that FZD8 promotes GC invasion and metastasis via the β-catenin pathway.

Long non-coding RNA is an endogenous non-coding RNA that has currently been proved to be an important player in cancer cell biology. In the present study, we investigated the biological role of PHACTR2-AS1 in tongue squamous cell carcinoma (TSCC). PHACTR2-AS1 was preferentially localized in the cytoplasm, and was notably upregulated in TSCC tissues. High PHACTR2-AS1 was correlated with tumour differentiation, metastatic clinical features, relapse and shortened survival time. Depletion of PHACTR2-AS1 did not affect TSCC cell viability and colony formation ability, whereas substantially inhibited cell migration and invasion in vitro and lung metastasis in vivo. Mechanistically, PHACTR2-AS1 could sponge miR-137 to increase Snail expression, resulting in triggering epithelial-mesenchymal transition process, thereby promoting TSCC cell metastasis. Taken together, our data for the first time elucidate the metastasis-promoting role of PHACTR2-AS1 in TSCC, hinting a new therapeutic target for metastatic TSCC patients.