Therapeutic Target For Intrahepatic Cholangiocarcinoma Research Articles

Protein tyrosine phosphatase PTP4A1 promotes proliferation and epithelial-mesenchymal transition in intrahepatic cholangiocarcinoma via the PI3K/AKT pathway.

The protein tyrosine phosphatase PTP4A1 is a key molecule that activates tyrosine phosphorylation, which is important for cancer progression and metastasis. However, the clinical implications and biological function of PTP4A1 in intrahepatic cholangiocarcinoma (ICC) remains unknown. Here, we showed that PTP4A1 was frequently overexpressed in ICC versus adjacent non-tumor tissues. This overexpression significantly correlated with aggressive tumor characteristics like the presence of lymph node metastasis and advanced tumor stages. Survival analysis further indicated that high PTP4A1 expression was significantly and independently associated with worse survival and increased recurrence in ICC patients. Moreover, through forced overexpression and knock-down of PTPT4A1, we demonstrated that PTP4A1 could significantly promote ICC cells proliferation, colony formation, migration, and invasion in vitro, and markedly enhance tumor progression in vivo. Mechanistically, PTP4A1 was involved in PI3K/AKT signaling and its downstream molecules, such as phosphorylation level of GSK3β and up-regulation of CyclinD1, in ICC cells to promote proliferation. Importantly, PTP4A1 induced ICC cells invasion was through activating PI3K/AKT signaling controlled epithelial-mesenchymal transition (EMT) process by up-regulating Zeb1 and Snail. Thus, PTP4A1 may serve as a potential oncogene that was a valuable prognostic biomarker and therapeutic target for ICC.

LOXL2 is a prognosis biomarker and a potential therapeutic target in intrahepatic cholangiocarcinoma

Aims: Intrahepatic cholangiocarcinoma (ICC) is associated with a poor prognosis related to early recurrence especially in the remnant liver following surgery. ICC exhibit a dense desmoplastic stroma which plays a pivotal role in ICC aggressiveness. Thus, analyzing gene deregulation in the stroma of ICC may help to identify new biomarkers and promising therapeutic targets. The aim of this study was to evaluate the clinical relevance of the matrix-remodeling enzyme lysyl oxidase-like 2 (LOXL2) expression in ICC. Methods: LOXL2 expression was evaluated at mRNA level in microdissected tumoral stroma (TS) and in non tumoral fibrous tissue (NFT): by gene expression profiling, n=10 (testing set), and by qPCR, n=6 (validating set). Secondly, LOXL2 expression was confirmed by immunohistochemistry (IHC) on a tissue micro array (TMA) containing an independent cohort, n=80. The relationship between LOXL2 expression and survival was assessed by univariate and multivariate analyses. Results: LOXL2 was up regulated at mRNA level in TS, both in the testing set as in the validating set (P<0.01). These results were confirmed at protein level, showing a significantly higher immunostaining in TS (P<0.01). Univariate analysis revealed that LOXL2 staining was correlated with poor overall survival (OS) and disease free survival (DFS) (P<0.01). Moreover, high expression of LOXL2 was an independent prognostic marker of OS (HR=5.29, IC95%(1.71–16.3), P<0.01) as well as DFS (HR=5.55, IC95%(2.14–14.37), P<0.01). Conclusions: Our study provides new arguments for the pivotal role of the stroma in ICC progression and reveals a new prognostic marker. LOXL2 over expression was directly correlated with the aggressiveness of ICC and should be now routinely performed by IHC. Moreover, targeting LOXL2 by neutralizing antibodies might represent an appealing strategy, which should be explorer in the context of personalized therapy.

SATB1 is a potential therapeutic target in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary malignant tumor of the liver with a poor prognosis. Upregulation of special AT-rich sequence-binding protein 1 (SATB1) promotes tumor progression. However, little is known about the role of SATB1 in ICC tumorigenesis. We firstly investigated the expression of SATB1 in 88 cases of ICC by immunohistochemistry (IHC), QRT-PCR, and western blot. Meanwhile, we constructed stably knockdown (shRNA) of SATB1 in ICC cell lines to evaluate the effects of SATB1 on the ability of cell proliferation and invasion by MTT and transwell invasion assay. Our result showed that SATB1 was overexpressed in ICC tissues samples. Knockdown of SATB1 could inhibit ICC cell proliferation, and suppress ICC cell invasion of ICC cell lines. In addition, the depletion of SATB1 expression suppressed the MYC levels in vitro. Our results highlight the significance of SATB1 in ICC and suggest that SATB1 could be a promising therapy target and a potential biomarker for prognosis in ICC patients.

MicroRNA-101 inhibits the migration and invasion of intrahepatic cholangiocarcinoma cells via direct suppression of vascular endothelial growth factor-C.

MicroRNAs (miRs) have important roles in the pathogenesis of human malignancy. It has previously been suggested that deregulation of miR‑101 is associated with the progression of intrahepatic cholangiocarcinoma (ICC); however, the exact role of miR‑101 in the regulation of ICC metastasis remains largely unknown. The present study demonstrated that the expression levels of miR‑101 were significantly decreased in ICC tissue, as compared with matched adjacent normal tissue. Furthermore, miR‑101 was downregulated in the ICC‑9810 human ICC cell line, as compared with in the normal human intrahepatic biliary epithelial cell (HIBEC) line. Vascular endothelial growth factor (VEGF)‑C was identified as a target gene of miR‑101 in ICC‑9810 cells. The expression of VEGF‑C was negatively regulated by miR‑101 at the post‑transcriptional level in ICC‑9810 cells. Further investigation demonstrated that overexpression of miR‑101 markedly suppressed the migration and invasion of ICC‑9810 cells, and these effects were similar to those observed following VEGF‑C knockdown. Conversely, restoration of VEGF‑C reversed the inhibitory effects of miR‑101 overexpression on ICC‑9810 cell migration and invasion, thus suggesting that miR‑101 may suppress ICC‑9810 cell migration and invasion, at least partly via inhibition of VEGF‑C. It was also demonstrated that the mRNA and protein expression levels of VEGF‑C were frequently upregulated in ICC tissue and cells, and its expression level was inversely correlated with that of miR‑101 in ICC tissue. In conclusion, the present study identified important roles for miR‑101 and VEGF‑C in ICC, suggesting that miR‑101/VEGF‑C signaling may be a promising diagnostic and/or therapeutic target for ICC.

SALL4 is a novel therapeutic target in intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (ICC) is the most common and deadly disease of the biliary tree due to its poor prognosis. Sal-like protein 4 (SALL4), a stem cell marker, has been identified as a potential target for aggressive hepatocellular carcinoma (HCC). In our study, 175 ICC cases with an average age of 55 years were included, and 53% (93/175) were male. And 28 adjacent non-tumor tissues were also collected. The SALL4-positive immunoreactivity was detected in a total of 102 ICC cases (58%), whereas all 28 adjacent tissues showed negative staining. Univariate analysis, showed that the SALL4-positive ICC cases had significantly more frequent lymph nodal metastasis (P = 0.0460), vascular invasion (P < 0.0001), and nerve invasion (P < 0.0001). Furthermore, the strong SALL4-positive cases (n = 7, 5 months) had shorter overall survival, when compared to moderate SALL4-positive (n = 46, 9 months) or SALL4-negative cases (n = 73, 7 months), respectively. Our data also suggest that SALL4 may be involved in the regulation of epithelial-mesenchymal transition (EMT) in ICC. Those results for the first time indicate an oncogenic role of SALL4 in ICC. Therefore, SALL4 may serve as a promising therapeutic target for ICC.

High Expression of Protein Tyrosine Kinase 7 Significantly Associates with Invasiveness and Poor Prognosis in Intrahepatic Cholangiocarcinoma

BackgroundThe incidence, prevalence, and mortality of intrahepatic cholangiocarcinoma (ICC) are increasing worldwide. Protein tyrosine kinase-7 (PTK7) is upregulated in many common human cancers. However, its expression in ICC has not been studied. The present study aimed to explore the underlying mechanism of PTK7 in ICC.Materials and MethodsThe role of PTK7 was studied in vitro by suppressing PTK7 expression in ICC cell lines. The in vivo effect of PTK7 was evaluated using a nude mouse model inoculated with a human ICC cell line. We also examined the role of PTK7 in human ICC samples.ResultsCells with high PTK7 expression exhibited higher proliferation, DNA synthesis, invasion, and migration abilities than did cells with low PTK7 expression. The knockdown of PTK7 with small interfering RNA (siRNA) in high PTK7 expressing cells resulted in impairment of invasion, migration, and DNA synthesis through the regulation of several cell-cycle-related proteins. It also induced cell apoptosis and decreased phospho-RhoA expression. In a xenograft nude mouse model, PTK7 siRNA resulted in a reduction of the tumor size, compared with scrambled siRNA injection. PTK7 expression was higher in human ICC than in the normal bile duct. Patients with low expression of PTK7 had a longer disease-free survival and overall survival than those with high expression.ConclusionsPTK7 expression plays an important role in the invasiveness of ICC cells and leads to a poor prognosis in ICC patients. Thus, PTK7 can be used as a prognostic indicator, and the inhibition of PTK7 expression could be a new therapeutic target for ICC.

L1 Cell Adhesion Molecule Is a Novel Therapeutic Target in Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC), a highly malignant hepatobiliary cancer, has a poor prognosis and is refractory to conventional therapies. The aim of this study is to discover a novel molecular target for the treatment of ICC. To discover novel cancer-associated membrane antigens expressed in ICC cells, we generated monoclonal antibodies (mAb) by immunizing mice with intact ICC cell lines and screened for those that bind to the plasma membrane of ICC cells but not to normal cells. The mAb A10-A3 was selected and its target antigen was identified as the L1 cell adhesion molecule. Expression of L1 in ICC was evaluated by immunohistochemical analysis of tumor samples from 42 ICC patients. The functional significance of L1 expression in the tumor progression of ICC was investigated by L1 suppression, L1 overexpression, and antibody treatment. L1 was not expressed in normal hepatocytes and intrahepatic bile duct epithelium but highly expressed in 40.5% of ICC patients, remarkably at the invasive front of the tumors. Suppression of L1 with short hairpin RNA significantly decreased proliferation, migration, and invasion of ICC cells in vitro. Consistently, L1 overexpression in ICC cells enhanced proliferation, migration, invasion, and apoptosis resistance. In addition, L1 short hairpin RNA or anti-L1 mAb significantly reduced the tumor growth in nude mice bearing ICC xenograft. We identified that L1 is expressed in ICC. L1 plays an important role in the tumor progression of ICC by enhancing cell proliferation, migration, invasion, and survival. L1 may represent a novel therapeutic target for ICC.