Is recurrent pyogenic cholangitis an independent poor prognostic indicator for resectable intrahepatic cholangiocarcinoma?

Mesencephalic Astrocyte-Derived Neurotrophic Factor, a Prognostic Factor of Cholangiocarcinoma, Affects Sorafenib Sensitivity of Cholangiocarcinoma Cells by Deteriorating ER Stress

Purpose

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignant tumor characterized by high malignancy and poor prognosis. Although the efficacy of sorafenib against cholangiocarcinoma cell lines has been demonstrated in vivo and in vitro, limited clinical data are available on the efficacy of sorafenib in patients with cholangiocarcinoma. Sorafenib can enhance endoplasmic reticulum (ER) stress-mediated apoptosis, and ER stress and unfolded protein response are also the mechanisms by which cancer cells resist drug therapy. Mesencephalic astrocyte-derived neurotrophic factor (MANF), initially identified as a neurotrophic factor, can be regulated by ER stress activation. There are no available studies on the diagnostic value and therapeutic significance of MANF in ICC. Hence, the purpose of this study was to evaluate the role of MANF in cholangiocarcinoma, investigating the possibility of whether sorafenib could become a reliable strategy for cholangiocarcinoma therapy.

Methods

In this study, the expression level of MANF in ICC patients was investigated by bioinformatic analysis and the results were verified by tissue microarray assay. Cholangiocarcinoma cell lines were also used to determine how MANF regulates the therapeutic effect of sorafenib and to identify the underlying mechanisms.

Results

The results showed that MANF was correlated with poor prognosis and MANF knockdown could facilitate sorafenib-mediated apoptosis and increase the sensitivity of sorafenib treatment by activating excessive ER stress.

Conclusion

MANF is a prognostic marker of cholangiocarcinoma. MANF knockdown increases sorafenib-mediated ER stress and apoptosis in the cholangiocarcinoma cell lines. This mechanism may lead to a new therapeutic strategy in cholangiocarcinoma.

Downregulation of Fat Mass and Obesity Associated (FTO) Promotes the Progression of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) ranks as the second most malignant type of primary liver cancer with a high degree of incidence and a very poor prognosis. Fat mass and obesity-associated protein (FTO) functions as an eraser of the RNA m6A modification, but its roles in ICC tumorigenesis and development remain unknown. We showed here that the protein level of FTO was downregulated in clinical ICC samples and cell lines and that FTO expression was inversely correlated with the expression of CA19-9 and micro-vessel density (MVD). A Kaplan-Meier survival analysis showed that a low expression of FTO predicted poor prognosis in ICC. in vitro, decreased endogenous expression of FTO obviously reduced apoptosis of ICC cells. Moreover, FTO suppressed the anchorage-independent growth and mobility of ICC cells. Through mining the database, FTO was found to regulate the integrin signaling pathway, inflammation signaling pathway, epidermal growth factor receptor (EGFR) signaling pathway, angiogenesis, and the pyrimidine metabolism pathway. RNA decay assay showed that oncogene TEAD2 mRNA stability was impaired by FTO. In addition, the overexpression of FTO suppressed tumor growth in vivo. In conclusion, our study demonstrated the critical roles of FTO in ICC.