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Replication-competent oncolytic herpes simplex viruses (HSV), modified by deletion of certain viral growth genes, can selectively target malignant cells. The viral growth gene gamma(1)34.5 has significant homology to GADD34 (growth arrest and DNA damage protein 34), which promotes cell cycle arrest and DNA repair in response to stressors such as radiation (XRT). By upregulating GADD34, XRT may result in greater oncolytic activity of HSV strains deficient in the gamma(1)34.5 gene. The human cholangiocarcinoma cell lines KMBC, SK-ChA-1 and YoMi were treated with NV1023, an oncolytic HSV lacking one copy of gamma(1)34.5. Viral proliferation assays were performed at a multiplicity of infection (MOI, number of viral particles per tumor cell) equal to 1, either alone or after XRT at 250 or 500 cGy. Viral replication was assessed by plaque assay. In vitro cytotoxicity assays were performed using virus at MOIs of 0.01 and 0.1, with or without XRT at 250 cGy and cell survival determined with lactate dehydrogenase assay. Established flank tumors in athymic mice were treated with a single intratumoral injection of virus (10(3) or 10(4) plaque forming units), either alone or after a single dose of XRT at 500 cGy, and tumor volumes measured. RT-PCR was used to measure GADD34 mRNA levels in all cell lines after a single dose of XRT at 250 or 500 cGy. NV1023 was tumoricidal in all three cell lines, but sensitivity to the virus varied. XRT enhanced viral replication in vitro in all cell lines. Combination treatment with low-dose XRT and virus was highly tumoricidal, both in vitro and in vivo. The greatest tumor volume reduction with combination therapy was seen with YoMi cells, the only cell line with increased GADD34 expression after XRT and the only cell line in which a synergistic treatment effect was suggested. In KMBC and SK-ChA-1 cells, neither of which showed increased GADD34 expression after XRT, tumor volume reduction was less pronounced and there was no suggestion of a synergistic effect in either case. Oncolytic HSV are effective in treating human cholangiocarcinoma cell lines, although sensitivity to virus varies. XRT-enhanced viral replication occurs through a mechanism that is not necessarily dependent on GADD34 upregulation. However, XRT-induced upregulation of GADD34 further promotes tumoricidal activity in viral strains deficient in the gamma(1)34.5 gene, resulting in treatment synergy; this effect is cell type dependent. Combined XRT and oncolytic viral therapy is a potentially important treatment strategy that may enhance the therapeutic ratios of both individual therapies.

Purpose: Biliary tract adenocarcinomas (BTAs), although anatomically related, arise through ill-defined and possibly different location-related pathogenetic pathways. This clinicopathologic study characterizes differences in cell cycle-regulatory protein expression across the spectrum of BTA., Methods: Tissue microarrays were prepared from paraffin-embedded surgical specimens with triplicate cores of BTA and benign tissue. Immunohistochemical expression of p53, cyclin D1, p21, Bcl2, p27, Mdm2, and Ki-67 was assessed, and the results were correlated with pathologic variables and survival. Hierarchical clustering was used to partition the data based on protein expression, and then the data were analyzed according to anatomic location., Results: Tissue from 128 surgical patients (1992 to 2002) was obtained. Tumor sites of origin were intrahepatic cholangiocarcinoma (IH; n = 23), hilar cholangiocarcinoma (Hilar; n = 54), gallbladder (GB; n = 32), and distal bile duct (Distal; n = 19). p27 expression decreased progressively from proximal to distal in the biliary tree and correlated with location-related differences in outcome; cyclin D1 and Bcl2 overexpression also varied according to anatomic site. Aberrant p53 staining and cyclin D1 overexpression were lower in papillary tumors compared with the more common sclerosing tumors. The expression profiles of GB and Hilar were more similar to each other than either was to IH or Distal (86% clustering in the first partition). After an R0 resection, overexpression of Mdm2 (P = .0062) and absent p27 expression (P = .0165) independently predicted poor outcome., Conclusion: BTAs differentially express cell cycle-regulatory proteins based on tumor location and morphology. Prognostic roles were identified for Mdm2 and p27. Overlap in the pathogenesis of GB and Hilar tumors was suggested.