Although early stage cholangiocarcinoma (CC) can be cured by surgical extirpation, the options for treatment of advanced stage CC are very few and suboptimal. Oncolytic virotherapy using replication-competent vaccinia virus (VACV) is a promising new strategy to treat human cancers. The ability of oncolytic VACV GLV-1h68 to infect, replicate in, and lyse three human CC cell lines was assayed in vitro and in subcutaneous flank xenografts in athymic nude mice. In this study, we have demonstrated that GLV-1h68 effectively infects and lyses three CC cell lines (KMC-1, KMBC, and KMCH-1) in vitro. Expression of the viral marker gene ruc-gfp facilitated real-time monitoring of infection and replication. Furthermore in athymic nude mice, a single dose of GLV-1h68 significantly suppressed tumor growth. The treatment was well tolerated in all animals. Recombinant VACV GLV-1h68 has significant oncolytic ability against CC both in vitro and in vivo. GLV-1h68 has the potential to be used clinically as a therapeutic agent against CC.

Background Sorafenib is the standard systemic therapy for un-resectable or recurrent hepatocellular carcinoma (HCC) with minimal increase in survival. Therefore, there is a great need to develop novel therapies for advanced or recurrent HCC. One emerging field of cancer treatment involves oncolytic viruses that specifically infect, replicate within, and kill cancer cells. In this study we look at the ability of GLV-1h68, a recombinant vaccinia virus derived from the vaccine strain that was used to eradicate smallpox, to kill sorafenib-resistant HCC. Methods Four sorafenib-resistant HCC cell lines were generated by repeated passage in the presence of sorafenib. Median inhibitory concentration was determined for all cell lines. The infectivity, viral replication and cytotoxicity of GLV-1h68 were assayed for both parental and sorafenib-resistant HCC cells. Results Infectivity increased in a time and concentration dependent manner in all cell lines. All cell lines supported efficient replication of virus. No significant difference between the rates of cell death between the parental and sorafenib-resistant cell lines was observed. Conclusions Our results demonstrate that oncolytic vaccinia virus GLV-1h68 efficiently kills both parental and sorafenib-resistant HCC cell lines. This study indicates that patients who have failed treatment with sorafenib remain viable candidates for oncolytic therapy.

Background Hepatocellular carcinoma (HCC) commonly presents at a late stage when surgery is no longer a curative option. As such, novel therapies for advanced HCC are needed. Oncolytic viruses are a viable option for cancer therapy due to their ability to specifically infect, replicate within, and kill cancer cells. In this study we investigate the ability of GLV-2b372, a novel light-emitting recombinant vaccinia virus derived from a wild-type Lister strain, to kill HCC. Methods Four human HCC cell lines were assayed in vitro for infectivity and cytotoxicity. Viral replication was quantified via standard viral plaque assays. Flank HCC xenografts generated in athymic nude mice were treated with intratumoral GLV-2b372 to assess for tumor growth inhibition and viral biodistribution. Results Infectivity occurred in a time and concentration dependent manner with 70% cell death in all cell lines by day 5. All cell lines supported efficient viral replication. At 25 days post infection, flank tumor volumes decreased by 50% while controls increased by 400%. Tumor tissue demonstrated substantial GLV-2b372 infection at 24 hours, 48 hours and at 2 weeks. Conclusions We demonstrate that GLV-2b372 efficiently kills human HCC in vitro and in vivo and is a viable treatment option for patients with HCC.

Background Peritoneal carcinomatosis (PC) is a terminal progression of colorectal cancer (CRC). Poor response to cytoreductive surgery and chemotherapy, coupled with the inability to reliably track disease progression using established diagnostic methods make this a deadly disease. This paper examines the effectiveness of the oncolytic vaccinia virus GLV-1h153 as a therapeutic and diagnostic vehicle. We believe that viral expression of the human sodium iodide transporter (hNIS) can provide both real-time monitoring of viral therapy and effective treatment of colorectal peritoneal carcinomatosis (CRPC). Methods Infectivity and cytotoxic effect of GLV-1h153 on CRC cell lines was assayed in-vitro. Viral replication was examined by standard viral plaque assays. Orthotopic CRPC xenografts were generated in athymic nude mice, and subsequently administered GLV-1h153 intraperitoneally. Reduction of tumor burden was assessed by mass. Orthotopic tumors were visualized by SPECT/CT after Iodine (131I) administration and by fluorescence optical imaging. Results GLV-1h153 infected and killed CRC cells in a time and concentration dependent manner. Viral replication demonstrated greater than a 2.35 log increase in titer over 4 days. Intraperitoneal treatment of orthotopic CRPC xenografts resulted in a significant reduction of tumor burden. Infection of orthotopic xenografts was both therapeutic and facilitated monitoring by 131I-SPECT/CT via expression of hNIS in infected tissue. Conclusions GLV-1h153 effectively kills CRC in-vitro and dramatically reduces tumor burden in-vivo. We demonstrate that GLV-1h153 can be used as an agent to provide accurate delineation of tumor burden in-vivo. These findings indicate that GLV-1h153 has significant potential for use as theragnostic agent in the treatment of CRPC.

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