Tsung-Wen Chen

Surgical management in metastatic gastrointestinal stromal tumor (GIST) patients after imatinib mesylate treatment

Imatinib mesylate (IM) demonstrates substantial efficacy in most patients with metastatic gastrointestinal stromal tumors (GISTs). However, progression of GIST eventually develops and emerges as a challenge. To assess the role of surgery in the multidisciplinary management of GISTs, we studied the surgical outcomes in GIST patients receiving IM.

Sunitinib for Taiwanese patients with gastrointestinal stromal tumor after imatinib treatment failure or intolerance.

AIM To report preliminary results of the efficacy and safety of sunitinib in the management of Taiwanese gastrointestinal stromal tumors (GIST) patients facing imatinib mesylate (IM) intolerance or failure. METHODS Between 2001 and May 2010, 199 Taiwanese patients with metastatic GIST were treated at Chang Gung Memorial Hospital. Among them, 23 (11.6%) patients receiving sunitinib were investigated. RESULTS Sixteen male and 7 female patients with a median age of 59 years (range: 24-83 years) received sunitinib. Twenty-two GIST patients changed to sunitinib because of IM failure and 1 because of intolerance. The median duration of sunitinib administration was 6.0 mo (range: 2-29 mo). The clinical benefit was 65.2% [2 complete response (CR), 4 partial response (PR), and 9 stationary disease (SD); 15/23]. In 12 patients harboring mutations of the kit gene at exon 11, the clinical benefit rate (CR, PR, and SD) was 75.0% and 6 patients with tumors containing kit exon 9 mutations had a clinical benefit of 50.0% (not significant, P = 0.344). The progression free survival (PFS) and overall survival (OS) did not differ between patients whose GISTs had wild type, KIT exon 9, or KIT exon 11 mutations. Hand-foot syndrome was the most common cause of grade III adverse effect (26.1%), followed by anemia (17.4%), and neutropenia (13.0%). During the median 7.5-mo follow-up after sunitinib use, the median PFS and OS of these 23 GIST patients after sunitinib treatment were 8.4 and 14.1 mo, respectively. CONCLUSION Sunitinib appears to be an effective treatment for Taiwanese with IM-resistant/intolerant GISTs and induced a sustained clinical benefit in more than 50% of Taiwanese advanced GIST patients.

Expression of ezrin is associated with invasion and dedifferentiation of hepatitis B related hepatocellular carcinoma

BackgroundHepatocellular carcinoma (HCC) is the fifth most common malignancy in the world and constitutes the leading cause of cancer-related death among men, and second among women in Taiwan. Liver cirrhosis and HCC are relatively prevalent, and 80% to 85% of the patients with these conditions have positive results for hepatitis B surface antigen in Taiwan. Only 5% of the general population is seronegative for all hepatititis B virus (HBV) markers. This is the first study to determine the role of ezrin upon HBV HCC cell and patients with HBV HCC undergoing hepatectomyMethodsImmunohistochemical study with ezrin in 104 human HBV-HCC cases were carried out to investigate its association with the clinicopathological features and the outcomes of 104 HBV-HCC patients undergoing hepatetomy. In addition, DNA constructs including the wild type ezrin (wt-ezrin) and mutant ezrin Tyr353 (Y353) were transfected into Hep3B cell to study its role in tumor invasion and differentiation.ResultsHBV HCC patients with ezrin over-expression independently have smaller tumor size, cirrhotic liver background, poor tumor differentiation, and more vascular invasion. Ezrin expression status has no impact on survival for HBV-HCC patients undergoing hepatectomy. The in vitro assay showed that wt-ezrin Hep3B cells have a significant higher level of AFP secretion and higher invasion ability as compared with the control and Y353- ezrin Hep3B cells.ConclusionEzrin over-expression contributed to de-differentiation and invasion of HBV-HCC cell. HBV-HCC patients with ezrin over-expression were independently associated with tumor with smaller size, cirrhotic liver background, poor differentiation, and vascular invasion.

Fas/Fas Ligand Mediates Keratinocyte Death in Sunitinib-Induced Hand-Foot Skin Reaction

Sunitinib, a multitargeted receptor Y kinase inhibitor (TKI) used for the treatment of renal cell carcinoma and gastrointestinal stromal tumor (GIST), is notorious for cutaneous adverse effects, such as hand-foot skin reaction (HFSR). To explore the underlying mechanism of HFSR, we enrolled 53 sunitinib-treated GIST patients, including 23 HFSR cases, and 30 tolerant controls. Among the 29 biomarkers examined, soluble FasL (sFasL) showed significant increase in the plasma, blister fluids, and skin lesions of HFSR patients. The plasma levels of sFasL were significantly correlated with those of sunitinib in HFSR patients. In addition to FasL, augmented expression of Fas and active caspase 3 was also detected in the epidermis of HFSR patients. The increased FasL caused keratinocyte death, as the use of anti-FasL antibody specifically blocked cell apoptosis. Oral administration of sunitinib to mice increased skin susceptibility to mechanical injuries in a dose/time-dependent manner. The administration of sunitinib (40 mg kg(-1) per day) for 4 weeks to mice caused the maximally affected skin area with an erosion-to-ulceration response to tape-stripping. The skin biopsies of mice administered sunitinib exhibited increased expression of Fas and FasL in the apoptotic keratinocytes in the epidermis. Our data revealed that Fas/FasL interaction mediates keratinocyte death in sunitinib-induced HFSR.

Gene expression‐based chemical genomics identifies heat‐shock protein 90 inhibitors as potential therapeutic drugs in cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive tumor with a poor prognosis. There is no standard therapy for CCA, and novel drugs for treating refractory CCA need to be identified.

Characterization of a novel rat cholangiocarcinoma cell culture model-CGCCA

AIM To characterize a culture model of rat CCA cells, which were derived from a transplantable TTA-induced CCA and designated as Chang Gung CCA (CGCCA). METHODS The CGCCA cells were cultured at in vitro passage 12 times on a culture dish in DMEM medium. To measure the doubling time, 10(3) cells were plated in a 96-well plate containing the growth medium. The cells were harvested 4 to 10 d after seeding, and a standard MTT assay was used to measure the growth. The phenotype of CACCA cell and xenograft was determined by immunohistochemical study. We also determine the chromosomal alterations of CGCCA, G-banding and spectral karyotyping studies were performed. The CGCCA cell line was transplanted into the nude mice for examining its tumorigenicity. 2-Deoxy-2-((18)F)fluoro-D-glucose (FDG) autoradiography was also performed to evaluate the FDG uptake of the tumor xenograft. RESULTS The doubling time for the CGCCA cell line was 32 h. After transplantation into nude mice, FDG autoradiography showed that the tumors formed at the cell transplantation site had a latency period of 4-6 wk with high FDG uptake excluding necrosis tissue. Moreover, immunohistochemical staining revealed prominent cytoplasmic expression of c-erb-B2, CK19, c-Met, COX-II, EGFR, MUC4, and a negative expression of K-ras. All data confirmed the phenotypic features of the CGCCA cell line coincide with the xenograft mice tumors, indicating cells containing the tumorigenicity of CCA originated from CCA. In addition, karyotypic banding analysis showed that the diploid (2n) cell status combines with ring and giant rod marker chromosomes in these clones; either both types simultaneously appeared or only one type of marker chromosome in a pair appeared in a cell. The major materials contained in the marker chromosome were primarily identified from chromosome 4. CONCLUSION The current CGCCA cell line may be used as a non-K-ras effect CCA model and to obtain information and reveal novel pathways for CCA. Further applications regarding tumor markers or therapeutic targeting of CCA should be addressed accordingly.

Cytoplasmic overexpression with membrane accentuation of stratifin in intrahepatic mass-forming cholangiocarcinoma after hepatectomy: correlation with clinicopathologic features and patient survival.

Cholangiocarcinoma (CCA) is a lethal malignancy that afflicts thousands of patients worldwide. Stratifin has been shown to participate in mediating G2 arrest in several cancers, and cells that express stratifin could contribute to the chemo‐ and radioresistance of cancers and poor prognosis. However, the clinical impact of stratifin on clinicopathological features of mass forming (MF)‐CCA is still unclear.

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.

Synthesis and characterization of boron fenbufen and its F-18 labeled homolog for boron neutron capture therapy of COX-2 overexpressed cholangiocarcinoma

Abstract Boron neutron capture therapy (BNCT) is a binary therapy that employs neutron irradiation on the boron agents to release high‐energy helium and alpha particles to kill cancer cells. An optimal response to BNCT depends critically on the time point of maximal 10B accumulation and highest tumor to normal ratio (T/N) for performing the neutron irradiation. The aggressive cholangiocarcinoma (CCA) representing a liver cancer that overexpresses COX‐2 enzyme is aimed to be targeted by COX‐2 selective boron carrier, fenbufen boronopinacol (FBPin). Two main works were performed including: 1) chemical synthesis of FBPin as the boron carrier and 2) radiochemical labeling with F‐18 to provide the radiofluoro congener, m‐[18F]fluorofenbufen ester boronopinacol (m‐[18F]FFBPin), to assess the binding affinity, cellular accumulation level and distribution profile in CCA rats. FBPin was prepared from bromofenbufen via 3 steps with 82% yield. The binding assay employed [18F]FFBPin to compete FBPin for binding to COX‐1 (IC50 = 0.91 ± 0.68 &mgr;M) and COX‐2 (IC50 = 0.33 ± 0.24 &mgr;M). [18F]FFBPin‐derived 60‐min dynamic PET scans predict the 10B‐accumulation of 0.8–1.2 ppm in liver and 1.2–1.8 ppm in tumor and tumor to normal ratio = 1.38 ± 0.12. BNCT was performed 40–55 min post intravenous administration of FBPin (20–30 mg) in the CCA rats. CCA rats treated with BNCT display more tumor reduction than that by NCT with respect of 2‐[18F]fluoro‐2‐deoxy glucose uptake in the tumor region of interest, 20.83 ± 3.00% (n = 12) vs. 12.83 ± 3.79% (n = 10), P = 0.05. The visualizing agent [18F]FFBPin resembles FBPin to generate the time‐dependent boron concentration profile. Optimal neutron irradiation period is thus determinable for BNCT. A boron‐substituted agent based on COX‐2‐binding features has been prepared. The moderate COX‐2/COX‐1 selectivity index of 2.78 allows a fair tumor selectivity index of 1.38 with a mild cardiovascular effect. The therapeutic effect from FBPin with BNCT warrants a proper COX‐2 targeting of boron NSAIDs. Graphical abstract Figure. No Caption available.

Over-expression of TNNI3K is Associated with Early-stage Carcinogenesis of Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a devastating disease with very poor prognosis due to late diagnosis and resistance to traditional chemotherapies and radiotherapies. Herein, thioacetamide (TAA)‐induced rat CCA model and CGCCA cell line were used; we aim to study the cytogenetic features during tumoral development of CCA and uncover the mystery regarding carcinogenesis of CCA. The Array comparative genomic hybridization analysis, in silico method, gene knockdown, Western blot, cell count proliferation assay, clonogenecity assay, and IHC staining were applied in this study. Array comparative genomic hybridization analysis was performed on all different TAA‐induced phases of rat tissues to reveal the certain pattern, +2q45, +Xq22, −12p12, have been identified for the tumor early stage, where involve the gene TNNI3K. In addition, 16 genes and 3 loci were associated with rapid tumor progression; JAK‐STAT signaling pathway was highly correlated to late stage of CCA. In silico database was used to observe TNNI3K was highly express at tumor part compared with normal adjacent tissue in CCA patients from TCGA dataset. Furthermore, the growth of TNNI3K‐knockdown SNU308 and HuCCT1 cells decreased when compared with cells transfected with an empty vector cell demonstrated by proliferation and colonogenecity assay. Besides, over expression of TNNI3K was especially confirmed on human CCA tumors and compared with the intrahepatic duct stone bile duct tissues and normal bile duct tissues (P < 0.001). Our findings might uncover the mystery regarding carcinogenesis of CCA, and provide the potential genetic mechanism to the clinicians some ideas for the patients’ treatment.