Matrix metalloproteinase-2 inducing COL1A1 synthesis via integrin alpha â ¤ promotes invasion and metastasis of cholangiocarcinoma cells.

INTRODUCTION AND OBJECTIVES: Cholangiocarcinoma (CCA) is characterized by early distant invasion and metastasis, whereas the underlying mechanism is still obscure. Increasing evidence shows that collagen type Ι alpha 1 (COL1A1) is a gene associated with the progression of multiple diseases. Here, we attempted to investigate the role of COL1A1 in CCA. MATERIALS AND METHODS: The expression of COL1A1 between tumor tissues and adjacent normal tissues obtained from CCA patients was detected by Western blot and immunofluorescence, followed by analysis of its clinical significance. Then, the biological effects of COL1A1 overexpression or knockdown on CCA cells were evaluated in vitro and in vivo. Finally, molecular mechanism of COL1A1 in regulating the invasion and metastasis of CCA cells was determined by a series of experiments. RESULTS: COL1A1 expression was significantly higher in CCA pathological tissues than in corresponding adjacent normal tissues. Analysis of 83 CCA patients showed that higher expression of COL1A1 was correlated with poorer patient prognosis. Notably, overexpression or knockdown experiments revealed that COL1A1 contributed to the migration and invasion, as well as epithelial-to-mesenchymal transition (EMT), in CCA cells. Further investigations demonstrated that matrix metalloproteinase-2 (MMP2) promoted COL1A1 upregulation via the integrin alpha Ⅴ pathway, therefore affecting ECM remodelling and inducing EMT in CCA cells. Moreover, COL1A1 expression was positively related to PD-1 and PD-L1 in CCA, and COL1A1 increased PD-L1 expression by activating the NF-κB pathway. CONCLUSIONS: COL1A1 plays an important role in regulating CCA progression and may act as a promising biomarker and therapeutic target for CCA.

Integration of transcriptome and cistrome analysis identifies RUNX1-target genes involved in pancreatic cancer proliferation.

The extremely high proliferation rate of tumor cells contributes to pancreatic cancer (PC) progression. Runt-related transcription factor 1(RUNX1), a key factor in hematopoiesis that was correlated with tumor progression. However, the role of RUNX1 in PC proliferation was still unclear. We found that RUNX1 was significantly upregulated in PC tissues and its expression was negatively associated with prognosis of PC patients in a multicenter analysis according to immunohistochemical (IHC). RUNX1 downregulation in PC resulted in a significantly reduced cell proliferation rate, which was consistent with in vivo subcutaneous tumor formation assay results. RNA-seq and ChIP-seq results revealed that a portion of target genes, including HAP1, GPRC5B, PTPN21, VHL and EN2, were regulated by RUNX1, a finding successfully validated by ChIP-qPCR, qRT-PCR and Western blot. Subsequently, IHC and proliferation assays showed these target genes to be dysregulated in PC, affecting tumor growth. Our data suggest that RUNX1 plays an oncogenic role in tumor proliferation and is a potential prognostic biomarker and therapeutic target for PC.

Platelet-derived PDGF promotes the invasion and metastasis of cholangiocarcinoma by upregulating MMP2/MMP9 expression and inducing EMT via the p38/MAPK signalling pathway.

Cholangiocarcinoma (CCA) is an aggressive tumour with a poor prognosis due to its late clinical presentation and the lack of effective non-surgical therapies. Previous studies have reported that platelets are implicated in tumour invasion and metastasis, while their role and the underlying mechanism in CCA remain unclear. Here, we show that platelets are hyperactivated in patients with CCA and that platelet-derived growth factor (PDGF) promotes the migration of CCA tumour cells both in vitro and in vivo. Further investigations revealed that PDGF can upregulate the expression of MMP2/MMP9 and induce epithelial-mesenchymal transition (EMT) by activating the p38/MAPK signalling pathway in CCA cells. In addition, the expression of MMP2/MMP9 was associated with lymph node metastasis and poor prognosis in CCA patients after surgical resection. In conclusion, our findings demonstrate that platelets play an important role in facilitating the invasion and metastasis of CCA cells by secreting PDGF, which may provide a novel target for CCA treatment.

Functional analysis of the correlation between ABCB11 gene mutation and primary intrahepatic stone.

The adenosine 5'­triphosphate binding cassette subfamily B member (ABCB)11 gene is involved in bile transport, and mutations in this gene are associated with cholestasis and cholelithiasis. Therefore, the aim of the present study was to investigate the association between ABCB11 gene mutation and primary intrahepatic stone (PIS)s and to investigate the mechanism through which ABCB11 gene mutations affect the expression of the corresponding protein. Mutations of the ABCB11 gene in 443 PIS patients and 560 healthy participants were detected by exon sequencing. The expression levels of ABCB11 mRNA and bile salt export pump (BSEP) protein in the liver tissues of patients with PISs were measured by quantitative polymerase chain reaction and western blot analysis. The mutant plasmids constructed by site­directed mutagenesis of the human BSEP gene were transfected into human embryonic kidney 293 (293) cells and Madin­Darby canine kidney (MDCK) cells, and the expression and distribution of rs118109635 of BSEP was measured. There were two significant mutations in the ABCB11 gene of the PIS patients compared with the healthy population; a missense mutation, rs118109635 (P=0.025), and a synonymous mutation, rs497692 (P=0.006). The two mutations were associated with the occurrence of preoperative jaundice (P=0.026, and P=0.011, respectively). The expression levels of BSEP in PIS patients with the missense mutation rs118109635 was decreased, whereas its mRNA expression levels remained unchanged. In PIS patients with the synonymous mutation rs497692, the expression levels of ABCB11 were decreased at both the mRNA and protein level. It was also found that mutation A865V reduced the expression levels of BSEP in 293 cells at the cellular level; its distribution in MDCK cell membranes was decreased, whereas its mRNA levels remained unchanged. The mutated loci at rs118109635 and rs497692 of the ABCB11 gene were correlated with PISs, causing a decreased expression of BSEP and reduced distribution of the protein in the cell membrane. Therefore, mutations at rs118109635 and rs497692 of the ABCB11 gene may be risk factors for PISs.

Tumor-derived exosomal lnc-Sox2ot promotes EMT and stemness by acting as a ceRNA in pancreatic ductal adenocarcinoma.

Long noncoding RNAs (lncRNAs) or exosomes have recently been shown to play vital regulatory or communication roles in cancer biology. However, the roles and mechanisms of exosomal lncRNAs in tumor invasion or metastasis of pancreatic ductal adenocarcinoma (PDAC) remain unknown. In this study, we aimed to investigate the detailed roles and mechanisms of tumor-generated exosomes in progression and metastasis of PDAC in vitro and in vivo. We identified a lncRNA-Sox2ot from exosomes of highly invasive PDAC cells, and analyzed the expression of Sox2ot in the plasma samples and found that the plasma exosomal Sox2ot expression was high and correlated with TNM stage and overall survival rate of PDAC patients. Further research showed that Sox2ot promotes epithelial-mesenchymal transition (EMT) and stem cell like properties by regulating Sox2 expression. Sox2ot competitively binds to the miR-200 family to regulate the expression of Sox2, thus promoting invasion and metastasis of PDAC. We also confirmed the transmission of the exosomes from producer cells to recipient PDAC cells, exosomal Sox2ot can promote tumor invasion and metastasis in vitro and in vivo. We further confirmed tumor generated exosomes could excrete to tumor cell or blood circulation in vivo condition. Finally, we observed a decreased exosomal Sox2ot expression in postoperative blood samples of PDAC patients. The exosomal lncRNA Sox2ot plays important roles in tumor progression and may be a useful maker for pancreatic cancer prognosis.