Chi-Tung Cheng

Integrating Bioinformatics and Clinicopathological Research of Gastrointestinal Stromal Tumors: Identification of Aurora Kinase A as a Poor Risk Marker

BackgroundFor completely resected primary gastrointestinal stromal tumors (GISTs), mitotic rate, tumor size, and tumor location are important risk factors for recurrence. However, molecular markers for recurrence are still lacking.MethodsWe reanalyzed GIST gene expression profile GSE8167 available from the Gene Expression Omnibus (GEO) and confirmed the prognostic influence of one selected gene, aurora kinase A (AURKA), in another cohort of 142 patients using immunohistochemistry (IHC).ResultsThirty-two cases in GSE8167 were classified into two risk groups with distinct recurrence-free survival (RFS) and expression profiles using modified criteria of Miettinen et al. from the Armed Forces Institute of Pathology (AFIP-Miettinen). AURKA was among the 19 genes common to the top 50 features of the high-risk phenotype and a 67-gene signature called the complexity index in sarcomas. AURKA was significantly overexpressed in the high-risk group, and patients with high AURKA expression had significantly worse RFS than those with low expression. In the IHC-validated cohort, AURKA expression was significantly higher in nongastric tumors than in gastric tumors and was significantly correlated with AFIP-Miettinen risk group. Univariate analysis showed that RFS was significantly influenced by tumor size, mitotic count, AFIP-Miettinen risk group classification, and AURKA expression. However, only tumor size (Pxa0=xa00.017), mitotic count (Pxa0=xa00.007), and AURKA expression (Pxa0=xa00.039) were identified as independent unfavorable prognostic factors for RFS in multivariate analysis.ConclusionsBy integrating bioinformatics and clinicopathological studies, AURKA was identified as a marker for high-risk GIST.

Lipocalin 2 (LCN2) is a promising target for cholangiocarcinoma treatment and bile LCN2 level is a potential cholangiocarcinoma diagnostic marker.

Cholangiocarcinoma (CCA) is a devastating disease due to resistance to traditional chemotherapies and radiotherapies. New therapeutic strategies against CCA are urgently needed. This study investigated the role of lipocalin-2 (LCN2) in human cholangiocarcinoma as a potential therapeutic target and diagnostic marker. So far, the role of LCN2 in cancer is still controversial and studies regarding the role of LCN2 in CCA are limited. LCN2 knockdown inhibited CCA cell growth in vitro and in vivo through induction of cell cycle arrest at G0/G1 phases and decreased metastatic potential due to repression of epithelial-mesenchymal transition (EMT). Overexpression of LCN2 in CCA cells increased cell metastatic potential. We showed for the first time that the N-myc downstream regulated gene 1 (NDRG1) and NDRG2, known as tumor suppressor genes, are negatively regulated by LCN2 in CCA cells. LCN2 concentration in bile was higher in patients with CCA than that in patients with gallstones, with a cutoff value of 20.08u2009ng/ml making this a potential diagnostic marker. Higher LCN2 expression was associated with worse survival in patients with CCA. LCN2 is a promising target for CCA treatment and bile LCN2 level is a potential diagnostic marker for CCA.

ALDH1A3, the Major Aldehyde Dehydrogenase Isoform in Human Cholangiocarcinoma Cells, Affects Prognosis and Gemcitabine Resistance in Cholangiocarcinoma Patients

Purpose: Intrahepatic cholangiocarcinoma is a fatal primary liver cancer resulting from diagnosis at an advanced stage. Understanding the mechanisms of drug resistance and metastasis of cholangiocarcinoma may improve the disease prognosis. Enhanced aldehyde dehydrogenase (ALDH) activity is suggested to be associated with increased drug resistance and the metastasis. This study aims to investigate the roles of the ALDH isoforms in cholangiocarcinoma. Experimental Design: Aldefluor assays, RT-PCR, and Western blot analysis were used to identify the major ALDH isoforms contributing to Aldefluor activity in human cholangiocarcinoma cell lines. We manipulated isoform expression in HuCCT1 cells to elucidate the role of ALDH1A3 in the malignant progression of these cells. Finally, we used immunohistochemical staining to evaluate the clinical significance of ALDH1A3 in 77 hepatectomized cholangiocarcinoma patients and an additional 31 patients with advanced cholangiocarcinoma who received gemcitabine-based therapy. Results: ALDHhigh cholangiocarcinoma cells not only migrated faster but were more resistant to gemcitabine. Among the 19 ALDH isoforms studied, ALDH1A3 was found to be the main contributor to Aldefluor activity. In addition, we also found that knockdown of ALDH1A3 expression in HuCCT1 cells markedly reduced not only their sensitivity to gemcitabine, which might be attributed to a decreased expression of ribonucleotide reductase M1, but also their migration. Most importantly, this enzyme was also identified as an independent poor prognostic factor for patients with intrahepatic cholangiocarcinoma, as well as a prognostic biomarker of gemcitabine-treated patients. Conclusions: ALDH1A3 plays an important role in enhancing malignant behavior of cholangiocarcinoma and serves as a new therapeutic target. Clin Cancer Res; 22(16); 4225–35. ©2016 AACR.

MART-10 represses cholangiocarcinoma cell growth and high vitamin D receptor expression indicates better prognosis for cholangiocarcinoma

Cholangiocarcinoma (CCA) is a devastating disease due to no effective treatments available. Since the non-mineral functions of vitamin D emerges, 1α,25(OH)2D3, the active form of vitamin D, has been applied in anti-cancer researches. In this study, we demonstrated that both the 1α,25(OH)2D3 analog, MART-10, and 1α,25(OH)2D3 possessed anti-growth effect on human CCA cells with MART-10 much more potent than 1α,25(OH)2D3. The growth inhibition of both drugs were mediated by induction of G0/G1 cell cycle arrest through upregulation of p27 and downregulation of CDK4, CDK6, and cyclin D3. Human neutrophil gelatinase associated lipocalin (NGAL) was found to be involved in 1α,25(OH)2D3 and MART-10 meditated growth inhibition for CCA as knockdown of NGAL decreased Ki-67 expression in SNU308 cells and rendered SNU308 cells less responsive to 1α,25(OH)2D3 and MART-10 treatment. Vitamin D receptor (VDR) knockdown partly abolished MART-10-induced inhibition of NGAL and cell growth in SNU308 cells. The xenograft animal study demonstrated MART-10 could effectively repressed CCA growth in vivo without inducing obvious side effects. The IHC examination of human CCA specimen for VDR revealed that higher VDR expression was linked with better prognosis. Collectively, our results suggest that MART-10 could be a promising regimen for CCA treatment.

Peritumoral SPARC expression and patient outcome with resectable intrahepatic cholangiocarcinoma

Background and objectives Cholangiocarcinoma (CCA) affects thousands worldwide with increasing incidence. SPARC (secreted protein acidic and rich in cysteine) plays an important role in cellular matrix interactions, wound repair, and cellular migration, and has been reported to prevent malignancy from growth. SPARC undergoes epigenetic silencing in pancreatic malignancy, but is frequently expressed by stromal fibroblasts adjacent to infiltrating pancreatic adenocarcinomas. CCA is also a desmoplastic tumor, similar to pancreatic adenocarcinoma. SPARC’s clinical influence on clinicopathological characteristics of mass-forming (MF)-CCA still remains unclear. In this study, we evaluate the expression of SPARC in tumor and stromal tissue to clarity its relation with prognosis. Methods Seventy-eight MF-CCA patients who underwent hepatectomy with curative intent were enrolled for an immunohistochemical study of SPARC. The expression of immunostaining of SPARC was characterized for both tumor and stromal tissues. We conducted survival analysis with 16 clinicopathological variables. The overall survival (OS) was analyzed by Kaplan–Meier analysis and Cox proportional hazards regression modeling. Results Thirty-three men and 45 women with MF-CCA were studied. Within total 78 subjects, 12 (15.4%) were classified as tumor negative/stroma negative, 37 (47.4%) as tumor positive/stroma negative, four (5.1%) as tumor negative/stroma positive, and 25 (32.1%) as tumor positive/stroma positive. With a median follow-up of 13.6 months, the 5-year OS was 14.9%. Cox proportional hazard analysis revealed that SPARC tumor positive and stromal negative immunostaining and curative hepatectomy predicted favorable OS in patients with MF-CCA after hepatectomy. Conclusion MF-CCA patients with SPARC tumor positive and stromal negative expression may have favorable OS rates after curative hepatectomy.

Surgical outcome evaluation of perforated gastric cancer: from the aspects of both acute care surgery and surgical oncology

Abstract Background: Perforated gastric cancer (PGC) is a rare condition of gastric cancer (GC). In this study, we sought to assess the outcome of PGC from the aspects of both acute care surgery and surgical oncology at a single institute, Chang Gung Memorial Hospital (CGMH). Methods: From 1997 to 2013, 6864 patients were diagnosed with GC and 2738 were diagnosed with gastroduodenal perforation at CGMH. In total, 29 patients with PGC were identified. Immediate surgical and long-term oncologic outcomes were evaluated after an appropriate matching process was performed. Results: The immediate surgical outcome of PGC, i.e., the hospital mortality rate within 30 d after surgery, did not significantly differ from that of non-cancer related gastroduodenal perforation. The long-term oncologic outcome, with matching by age, gender, year of surgery and AJCC 7th stage grouping, also did not significantly differ from that of GC without perforation. Conclusions: Aggressive surgical treatment, including an initial emergency procedure for containing peritonitis and radical surgery for GC, may benefit PGC patients in terms of both the immediate and oncologic outcomes.

Identification of MALT1 as both a prognostic factor and a potential therapeutic target of regorafenib in cholangiocarcinoma patients

Intrahepatic cholangiocarcinoma (CCA) is an aggressive cancer that lacks an effective targeted therapy. Here, we assessed the therapeutic efficacy of regorafenib in CCA, as well as elucidated its underlying mechanism. We first demonstrated that regorafenib not only inhibited growth but also induced apoptosis in human CCA cells. Subsequently, we used in silico approaches to identify MALT1 (Mucosa-associated lymphoid tissue protein 1), which plays an important role in activating NF-κB, as a potential target of regorafenib. Overexpression of Elk-1, but not Ets-1, in HuCCT1 cells markedly reduced their sensitivity to regorafenib, which might be attributed to a significant increase in MALT1 levels. Our results further demonstrated that this drug drastically inhibited MALT1 expression by suppressing the Raf/Erk/Elk-1 pathway. The efficacy of regorafenib in decreasing in vivo CCA growth was confirmed in animal models. Regorafenib efficacy was observed in two MALT1-positive CCA patients who failed to respond to several other lines of therapy. Finally, MALT1 was also identified as an independent poor prognostic factor for patients with intrahepatic CCA. In conclusion, our study identified MALT1 to be a downstream mediator of the Raf/Erk/Elk-1 pathway and suggested that MALT1 may be a new therapeutic target for successful treatment of CCA by regorafenib.

Abstract 1309: Identification of aurora kinase a as an unfavorable prognostic factor and potential treatment target for metastatic gastrointestinal stromal tumors

Purpose: Although imatinib mesylate (IM) has revolutionized the management of gastrointestinal stromal tumors (GISTs), drug resistance remains a challenge. Previous studies have shown that the expression of aurora kinase A (AURKA) predicts recurrence in patients with primary surgically-resected GISTs. The current study aims to evaluate the significance of AURKA as an unfavorable prognostic marker for advanced GISTs, and provides evidence that AURKA could be a potential treatment target of GISTs. Experimental Design: The prognostic significance of AURKA, along with other clinicopathological factors, was analyzed in a cohort of 99 IM-treated patients with advanced GISTs using immunohistochemistry. The potential use of an AURKA inhibitor as therapeutic agent against GISTs was also tested in GIST cell lines. Results: Among 99 enrolled patients, poor performance status, large tumor size, drug response, and AURKA overexpression were independent poor prognostic factors for progression-free survival (PFS). For overall survival (OS), only large tumor size and AURKA overexpression were identified as independent unfavorable factors. In an in vitro study, MLN8237, an AURKA inhibitor, was demonstrated to inhibit growth of both IM-sensitive and IM-resistant GIST cells in a concentration-dependent manner. The inhibitory effect of MLN8237 on GIST cells could be attributed to the induction of G2/M arrest, apoptosis, and senescence, possibly through up-regulation of pro-apoptotic proteins. Conclusions: Our study showed that AURAK is an independent poor prognostic factor for both PFS and OS in patients with advanced GISTs treated with IM. AURKA inhibitor could be used as therapeutic agent for both IM-sensitive and IM-resistant GISTs. Citation Format: Chun-Nan Yeh, Chueh-Chuan Yen, Yeng-Yang Chen, Chi-Tung Cheng, Shih-Chiang Huang, Ting-Wei Chang, Fang-Yi Yao, Yung-Chan Lin, Yao-Shan Wen, Kun-Chun Chiang, Jen-Shi Chen, Ta-Sen Yeh, Cheng-Hwai Tzeng, Ta-Chung Chao, Jonathan A. Fletcher. Identification of aurora kinase a as an unfavorable prognostic factor and potential treatment target for metastatic gastrointestinal stromal tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1309. doi:10.1158/1538-7445.AM2014-1309