Cell fusion is a fast and highly efficient technique for cells to acquire new properties. The fusion of somatic cells with stem cells can reprogram somatic cells to a pluripotent state. Our research on the fusion of stem cells and cancer cells demonstrates that the fused cells can exhibit stemness and cancer cell-like characteristics. Thus, tumor-initiating cell-like cells are generated. We employed laser-induced single-cell fusion technique to fuse the hepatocellular carcinoma cells and human embryonic stem cells (hESC). Real-time RT-PCR, flow cytometry and in vivo tumorigenicity assay were adopted to identify the gene expression difference. We successfully produced a fused cell line that coalesces the gene expression information of hepatocellular carcinoma cells and stem cells. Experimental results showed that the fused cells expressed cancer and stemness markers as well as exhibited increased resistance to drug treatment and enhanced tumorigenesis. Fusion with stem cells transforms liver cancer cells into tumor initiating-like cells. Results indicate that fusion between cancer cell and stem cell may generate tumor initiating-like cells.

Currently, the controversy regarding the expression profile and function of BUB1B in different malignancies still exist. In this project, we aimed to explore the role and molecular mechanism of BUB1B in the progression of extrahepatic cholangiocarcinoma (ECC). The expression levels of BUB1B in human ECC were evaluated by immunohistochemistry, western blot, and real-time PCR. The role and mechanism of BUB1B in CCA cell proliferation and invasion were investigated in both in vitro and in vivo functional studies. To indicate the clinical significance, a tissue microarray was performed on 113 ECC patients, followed by univariate and multivariate analyses. The expression of BUB1B was increased in both human CCA tissues and CCA cells. Results from loss-of-function and gain-of-function experiments suggested that the inhibition of BUB1B decreased the proliferation and invasiveness of CCA cells in vitro and in vivo, while overexpression of BUB1B achieved the opposite effect. Furthermore, the activation of c-Jun N-terminal kinase-c-Jun (JNK)-c-Jun pathway was regulated by BUB1B. BUB1B regulated the proliferation and invasiveness of CAA cells in a JNK-c-Jun-dependent manner. Clinically, ECC patients with BUB1B high expression had worse overall survival and recurrence-free survival than those with BUB1B low expression. Multivariate analysis identified that BUB1B was an independent predictor for postoperative recurrence and overall survival of ECC patients. In conclusion, BUB1B promoted ECC progression via JNK/c-Jun pathways. These findings suggested that BUB1B could be a potential therapeutic target and a biomarker for predicting prognosis for ECC patients.

Background: circular RNAs (circRNAs) have been reported to exert important effects in the progression of numerous cancers. However, the functions of circRNAs in intrahepatic cholangiocarcinoma (ICC) are still unclear. Methods: circPCNXL2 (has_circ_0016956) were identified in paired ICC by circRNA microarray. Then, we assessed the biological functions of circPCNXL2 by CCK8, EdU, clone formation, transwell, wound healing assays, and xenograft models. RNA pull-down, mass spectrometry, and RNA immunoprecipitation (RIP) were applied to explore the interaction between cirrcPCNXL2 and serine-threonine kinase receptor-associated protein (STRAP). RNA pull-down, RIP and luciferase reporter assays were used to investigate the sponge functions of circPCNXL2. In the end, we explore the effects of circPCNXL2 and trametinib (a MEK1/2 inhibitor) in vivo. Results: circPCNXL2 was upregulated in ICC tissues and cell lines, which promoted the proliferation and metastasis of ICC in vitro and in vivo. In terms of the mechanisms, circPCNXL2 could directly bind to STRAP and induce the interaction between STRAP and MEK1/2, resulting in the tumor promotion in ICC by activation of ERK/MAPK pathways. Besides, circPCNXL2 could regulate the expression of SRSF1 by sponging miR-766-3p and subsequently facilitated the growth of ICC. Finally, circPCNXL2 could partially inhibit the anti-tumor activity of trametinib in vivo. Conclusion: circPCNXL2 played a crucial role in the progression of ICC by interacting with STRAP to activate the ERK signaling pathway, as well as by modulating the miR-766-3p/SRSF1 axis. These findings suggest that circPCNXL2 may be a promising biomarker and therapeutic target for ICC.

Background: Cholangiocarcinoma (CHOL) is the second most common primary hepatic malignant tumor, following hepatocellular carcinoma (HCC). CHOL is highly aggressive and heterogeneous resulting in poor prognosis. The diagnosis and prognosis of CHOL has not improved in the past decade. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is reported to be associated with tumors, however, its role in CHOL has not been revealed. This study is mainly for exploring the prognostic values and potential function of ACSL4 in CHOL. Methods: We investigated the expression level and prognostic value of ACSL4 in CHOL based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. TIMER2.0, TISIDB and CIBERSORT databases were utilized to assess the associations between ACSL4 and immune infiltration cells in CHOL. Single-cell sequencing data from GSE138709 was analyzed to study the expression of ACSL4 in different types of cells. ACSL4 co-expressed genes were analyzed by Linkedomics. Additionally, Western Blot, qPCR, EdU assay, CCK8 assay, transwell assay and wound healing assay were performed to further confirm the roles of ACSL4 in the pathogenesis of CHOL. Results: We found that the level of ACSL4 was higher in CHOL and it was correlated with the diagnosis and prognosis of CHOL patients. Then, we observed that the infiltration level of immune cells was related to the level of ACSL4 in CHOL. Moreover, ACSL4 and its co-expressed genes were mainly enriched in metabolism-related pathway and ACSL4 is also a key pro-ferroptosis gene in CHOL. Finally, knockdown of ACSL4 could reverse the tumor-promoting effect of ACSL4 in CHOL. Conclusions: The current findings demonstrated ACSL4 may as a novel biomarker for CHOL patients, which might regulate immune microenvironment and metabolism resulting in poor prognosis.