Gene expression profiling of cholangiocarcinoma-derived fibroblast reveals alterations related to tumor progression and indicates periostin as a poor prognostic marker

Abstract

BackgroundFibroblasts play important roles in several cancers. It was hypothesized that cholangiocarcinoma (CCA)-associated fibroblasts (Cfs) differ from non-tumorigenic liver fibroblasts (Lfs) in their gene expression profiles resulting in the capability to promote cancer. Periostin (PN) is a multi-functional protein and has emerged as a promising marker for tumor progression. The role of PN in CCA, however, has not yet been explored.ResultsIn this study, the gene expression profile of Cfs in comparison to Lfs was performed using oligonucleotide microarrays. The common- and unique-expressed genes in Cfs and the promising roles in cancer promotion and progression were determined. PN was markedly over-expressed in Cfs confirmed by real time RT-PCR and western blot analysis. Immunohistochemistry examination of a number of patients with intrahepatic CCA showed the expression of PN solely in stromal fibroblasts, but was expressed neither in cancer cells nor immune cells. Low to no expression of PN was observed in tissues of benign liver disease and hepatocellular carcinoma. CCA patients with high levels of PN had significantly shorter survival time than those with low levels (P = 0.026). Multivariate analysis revealed high levels of PN (P = 0.045) and presence of lymph node metastasis (P = 0.002) as independent poor prognostic factors. The in vitro study revealed that recombinant PN induced CCA cell proliferation and invasion. Interestingly, interference RNA against integrin α5 significantly reduced the cellular response to PN-stimulated proliferation and invasion.ConclusionThe gene expression profile of fibroblasts in CCA is apparently explored for the first time and has determined the genes involving in induction of this cancer progression. High PN can be used to distinguish CCA from other related liver diseases and is proposed as a prognostic factor of poor survival. Regulation of fibroblast-derived PN in CCA proliferation and invasion may be considered as an alternative therapeutic approach.

Overexpression of periostin and distinct mesothelin forms predict malignant progression in a rat cholangiocarcinoma model

“…Postn immunoreactivity, which has been observed to colocalize with α‐SMA immunostaining in human6 and in rat BDEneu ICCs,1 was seen by us to be most extensive in the stroma of the more aggressive BDEneu liver cholangiocarcinomas of increasing tumor mass and anaplasia over that observed in the slow growing well‐differentiated BDEsp tumors and intermediate growing well‐to‐moderately differentiated TDE CC tumors. That Postn protein was also determined by both immunohistochemistry and western blotting to be more prominent in the larger sized BDEneu liver tumors than in the smaller BDEneu liver tumors also appears to reflect an increased accumulation of α‐SMA + CAFs within the enlarging desmoplastic stroma of the larger sized liver tumors 1.…”

“…Its potential as an independent prognostic risk factor for poor survival for patients with ICC was first suggested by Utispan et al,6 who demonstrated that surgically resected ICC patients with tumors strongly immunostained for CAF‐Postn had significantly shorter postoperative survival times than those expressing low levels of Postn. Benign liver diseases (e.g., liver cirrhosis, focal nodular hyperplasia) were further reported to show no‐to‐slight Postn immunoreactivity, and Postn expression was not detected in the cancer cells of conventional hepatocellular carcinoma (HCC) 6, 10. Patients with cholangiocarcinoma were also reported to exhibit a significantly higher median Postn level in their serum than those with normal liver, liver cirrhosis, HCC, or other malignancies 10.…”

“…The ultimate aim is to devise more effective strategies for the clinical management of advanced or recurrent ICC. In this context, the matricellular glycoprotein periostin (Postn) and the glycosylphosphatidylinositol‐anchored cell membrane glycoprotein mesothelin (Msln) have each been independently suggested as having potential as prognostic factors for human ICC 6, 7. Each may also provide opportunities for the development of novel targeted therapies for ICC 8, 9…”

“…Postn has been shown in both human and rat ICCs to be produced solely by α‐SMA + CAFs in the ICC stroma 6, 8. Its potential as an independent prognostic risk factor for poor survival for patients with ICC was first suggested by Utispan et al,6 who demonstrated that surgically resected ICC patients with tumors strongly immunostained for CAF‐Postn had significantly shorter postoperative survival times than those expressing low levels of Postn.…”

“…Notably, in their systematic review and meta‐analysis to investigate the prognostic value of immunohistochemically based biomarkers that have been assessed in patients with resected ICC, Ruys et al13 graded the study of Utispan et al6 on Postn as having a high risk of bias based on defined criteria to evaluate publication bias for biomarkers. Also, in contrast to the findings of Nomura et al,7 Higashi et al14 observed no significant difference in survival on resected ICC patients with Msln‐positive tumors compared with those that were Msln negative.…”