Experimental Evolution Generates Novel Oncolytic Vesicular Stomatitis Viruses with Improved Replication in Virus-Resistant Pancreatic Cancer Cells.

Vesicular stomatitis virus (VSV) based oncolytic viruses are promising agents against various cancers. We have shown that pancreatic ductal adenocarcinoma (PDAC) cell lines exhibit great diversity in susceptibility and permissibility to VSV. Here, using a directed evolution approach with our two previously described oncolytic VSV recombinants, VSV-p53wt and VSV-p53-CC, we generated novel oncolytic VSVs with an improved ability to replicate in virus-resistant PDAC cell lines. VSV-p53wt and VSV-p53-CC encode a VSV matrix protein (M) with a ΔM51 mutation (M-ΔM51) and one of two versions of a functional human tumor suppressor, p53, fused to a far-red fluorescent protein, eqFP650. Each virus was serially passaged 32 times (which accounts for more than 60 viral replication cycles) on either the SUIT-2 (moderately resistant to VSV) or MIA PaCa-2 (highly permissive to VSV) human PDAC cell lines. While no phenotypic changes were observed for MIA PaCa-2-passaged viruses, both SUIT-2-passaged VSV-p53wt and VSV-p53-CC showed improved replication in SUIT-2 and AsPC-1, another human PDAC cell line also moderately resistant to VSV, while remaining highly attenuated in nonmalignant cells. Surprisingly, two identical VSV glycoprotein (VSV-G) mutations, K174E and E238K, were identified in both SUIT-2-passaged viruses. Additional experiments indicated that the acquired G mutations improved VSV replication, at least in part due to improved virus attachment to SUIT-2 cells. Importantly, no mutations were found in the M-ΔM51 protein, and no deletions or mutations were found in the p53 or eqFP650 portions of virus-carried transgenes in any of the passaged viruses, demonstrating long-term genomic stability of complex VSV recombinants carrying large transgenes.IMPORTANCE Vesicular stomatitis virus (VSV)-based oncolytic viruses are promising agents against pancreatic ductal adenocarcinoma (PDAC). However, some PDAC cell lines are resistant to VSV. Here, using a directed viral evolution approach, we generated novel oncolytic VSVs with an improved ability to replicate in virus-resistant PDAC cell lines, while remaining highly attenuated in nonmalignant cells. Two independently evolved VSVs obtained 2 identical VSV glycoprotein mutations, K174E and E238K. Additional experiments indicated that these acquired G mutations improved VSV replication, at least in part due to improved virus attachment to SUIT-2 cells. Importantly, no deletions or mutations were found in the virus-carried transgenes in any of the passaged viruses. Our findings demonstrate long-term genomic stability of complex VSV recombinants carrying large transgenes and support further clinical development of oncolytic VSV recombinants as safe therapeutics for cancer.

Hepatitis C virus infection and non-hepatocellular malignancies in the DAA era: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Direct antiviral agents have greatly improved therapeutic options for chronic hepatitis C. Indeed, former "difficult-to-treat" patients can now be treated and can achieve sustained response. Hepatitis C virus (HCV) is associated with hepatocellular carcinoma and with B-cell non-Hodgkin lymphoma (B-NHL). Other malignancies have been reported to be associated with HCV infection albeit with various grades of evidence. Antineoplastic treatment is often reduced or suspended in HCV-positive cancer patients to avoid "HCV reactivation." In this setting, antiviral therapy combined with antineoplastic protocols may improve the outcome. For this reason, we conducted a systematic review and a meta-analysis to update the association between HCV infection and non-hepatocellular malignancies, and to shed light on the effects exerted by antiviral treatment on the natural history of oncological diseases. METHODS: Relevant studies were identified by searching PUBMED, EMBASE and MEDLINE up to 1 August 2018. Pooled risk estimates were calculated with random-effects models according to PRISMA guidelines. RESULTS: A total of 58 studies were included in the analysis: 27 studies of the association between HCV and B-NHL(OR 3.36; 95% CI 2.40-4.72;P < 0.00001);13 studies of the association between sustained virological response and progression-free survival (PFS) in B-NHL patients(OR 9.34; 95% CI 4.90-17.79; P < 0.00001); 13 studies of the association between HCV and intrahepatic-cholangio-carcinoma (OR 3.95;95% CI 2.25-6.94; P < 0.00001); and 5 studies of the association between HCV infection and pancreatic adeno-carcinoma(OR 1.60; 95% CI:1.25-2.04; P = 0.0002). CONCLUSIONS: This study updates the strong association between B-NHL and HCV infection, confirms the association between HCV and non-hepatocellular tumours, and demonstrates a very strong association between viral eradication and a better outcome of HCV-positive B-NHL.

Is Hepatitis B Virus a Player in Pancreatic Cancer?

Pancreatic cancer (i.e., pancreatic ductal adenocarcinoma, PDAC) is an important healthcare issue and a highly lethal disease. Thus, almost 80% of patients with PDAC will die within one year after diagnosis. Several factors including smoking, obesity, advanced age, diabetes mellitus and chronic pancreatitis have been associated with increased risk of PDAC. Hepatitis B virus (HBV) infection is also considered as a risk factor for PDAC development in some studies. However, the role of HBV infection in PDAC is poorly explored. The present paper reviews the current relevant literature exploring the impact of HBV infection in PDAC. Assessment of HBV infection impact in PDAC is challenging because its effects could be easily underestimated. Indeed, the role played by occult B infection (OBI) and intrinsic difficulties to detect HBV antigens or DNA in pancreatic tissue remains major limitations to further progress. To date a significant proportion of available literature suggests the potential oncogenic role of HBV in PDAC but experimental evidences remain scarce. Remarkably, it appears that HBV infection might influence some clinical and pathological features of patients with PDAC. Future researches to better define the role of HBV infection in developing PDAC are urgently needed.

Patient-derived xenografts of gastrointestinal cancers are susceptible to rapid and delayed B-lymphoproliferation.

Patient-derived cancer xenografts (PDX) are widely used to identify and evaluate novel therapeutic targets, and to test therapeutic approaches in preclinical mouse avatar trials. Despite their widespread use, potential caveats of PDX models remain considerably underappreciated. Here, we demonstrate that EBV-associated B-lymphoproliferations frequently develop following xenotransplantation of human colorectal and pancreatic carcinomas in highly immunodeficient NOD.Cg-Prkdcscid Il2rgtm1Wjl /SzJ (NSG) mice (18/47 and 4/37 mice, respectively), and in derived cell cultures in vitro. Strikingly, even PDX with carcinoma histology can host scarce EBV-infected B-lymphocytes that can fully overgrow carcinoma cells during serial passaging in vitro and in vivo. As serial xenografting is crucial to expand primary tumor tissue for biobanks and cohorts for preclinical mouse avatar trials, the emerging dominance of B-lymphoproliferations in serial PDX represents a serious confounding factor in these models. Consequently, repeated phenotypic assessments of serial PDX are mandatory at each expansion step to verify "bona fide" carcinoma xenografts.

Measles virus selectively blind to signaling lymphocyte activity molecule has oncolytic efficacy against nectin-4-expressing pancreatic cancer cells.

Pancreatic cancer is one of the most intractable cancers and has a devastating prognosis; over the past three decades the 5-year survival rate has been <10%. Therefore, development of a novel anticancer treatment for pancreatic cancer is a matter of urgency. We previously developed an oncolytic recombinant measles virus (MV), rMV-SLAMblind, that had lost the ability to bind to its principal receptor, signaling lymphocyte activity molecule (SLAM), but which selectively infected and efficiently killed nectin-4-expressing breast and lung cancer cells. In this study, we analyzed the antitumor effect of this virus against pancreatic cancer. Nectin-4 was expressed on the surface of 4/16 tested pancreatic cancer cell lines, which were efficiently infected and killed by rMV-SLAMblind in vitro. The intratumoral inoculation of rMV-SLAMblind suppressed the growth of KLM1 and Capan-2 cells xenografted in SCID mice. The sequence analysis of MV isolated from the tumor revealed that the designed mutation in the H protein of rMV-SLAMblind had been stably maintained for 47 days after the last inoculation. These results suggest that rMV-SLAMblind is a promising candidate for the novel treatment of pancreatic cancer.

Replication-competent adenoviruses with the type 35-derived fiber-knob region achieve reactive oxygen species-dependent cytotoxicity and produce greater toxicity than those with the type 5-derived region in pancreatic carcinoma.

Pancreatic carcinoma is relatively resistant to chemotherapy and cell death induced by replication of adenoviruses (Ad) can be one of the therapeutic options. Transduction efficacy of conventional type 5 Ad (Ad5) is however low and the cytotoxic mechanism by replication-competent Ad was not well understood. We constructed replication-competent Ad5 of which the E1A promoter region was replaced with a transcriptional regulatory region of the midkine, the survivin or the cyclooxygenase-2 gene, all of which were expressed at a high level in human tumors. We also prepared replication-competent Ad5 that were activated with the same region but had the type 35 Ad-derived fiber-knob region (AdF35) to convert the major cellular receptor for Ad infection from the coxsackie adenovirus receptor to CD46 molecules. Replication-competent AdF35 that were activated with the exogenous region produced cytotoxic effects on human pancreatic carcinoma cells greater than the corresponding Ad5 bearing with the same regulatory region. Cells infected with the AdF35 showed cytopathic effects and increased sub-G1 fractions. Caspase-9, less significantly caspase-8 and poly (ADP-ribose) polymerase, but not caspase-3 was cleaved and expression of molecules involved in autophagy and caspase-independent cell death pathways remained unchanged. Nevertheless, H2A histone family member X molecules were phosphorylated, and N-acetyl-L-cystein, an inhibitor for reactive oxygen species, suppressed the AdF35-mediated cytotoxicity. These data indicated a novel mechanism of Ad-mediated cell death and suggest a possible clinical application of the fiber-knob modified Ad.

Oncolytic activity of avian influenza virus in human pancreatic ductal adenocarcinoma cell lines.

UNLABELLED: Pancreatic ductal adenocarcinoma (PDA) is the most lethal form of human cancer, with dismal survival rates due to late-stage diagnoses and a lack of efficacious therapies. Building on the observation that avian influenza A viruses (IAVs) have a tropism for the pancreas in vivo, the present study was aimed at testing the efficacy of IAVs as oncolytic agents for killing human PDA cell lines. Receptor characterization confirmed that human PDA cell lines express the alpha-2,3- and the alpha-2,6-linked glycan receptor for avian and human IAVs, respectively. PDA cell lines were sensitive to infection by human and avian IAV isolates, which is consistent with this finding. Growth kinetic experiments showed preferential virus replication in PDA cells over that in a nontransformed pancreatic ductal cell line. Finally, at early time points posttreatment, infection with IAVs caused higher levels of apoptosis in PDA cells than gemcitabine and cisplatin, which are the cornerstone of current therapies for PDA. In the BxPC-3 PDA cell line, apoptosis resulted from the engagement of the intrinsic mitochondrial pathway. Importantly, IAVs did not induce apoptosis in nontransformed pancreatic ductal HPDE6 cells. Using a model based on the growth of a PDA cell line as a xenograft in SCID mice, we also show that a slightly pathogenic avian IAV significantly inhibited tumor growth following intratumoral injection. Taken together, these results are the first to suggest that IAVs may hold promise as future agents of oncolytic virotherapy against pancreatic ductal adenocarcinomas. IMPORTANCE: Despite intensive studies aimed at designing new therapeutic approaches, PDA still retains the most dismal prognosis among human cancers. In the present study, we provide the first evidence indicating that avian IAVs of low pathogenicity display a tropism for human PDA cells, resulting in viral RNA replication and a potent induction of apoptosis in vitro and antitumor effects in vivo. These results suggest that slightly pathogenic IAVs may prove to be effective for oncolytic virotherapy of PDA and provide grounds for further studies to develop specific and targeted viruses, with the aim of testing their efficacy in clinical contexts.

The combination of intravenous Reolysin and gemcitabine induces reovirus replication and endoplasmic reticular stress in a patient with KRAS-activated pancreatic cancer.

BACKGROUND: Activating mutations in RAS are present in the majority of pancreatic cancer cases and represent an ideal therapeutic target. Reolysin is a proprietary formulation of oncolytic reovirus that is currently being evaluated in multiple clinical trials due to its ability to selectively replicate in cells harboring an activated RAS pathway. Here we report for the first time the presence of reovirus replication and induction of endoplasmic reticular (ER) stress in a primary tumor specimen collected from a pancreatic cancer patient receiving intravenous Reolysin and gemcitabine. CASE PRESENTATION: We describe the case of a 54-year old patient diagnosed with pancreatic adenocarcinoma in February 2012. Analysis of a tumor biopsy revealed an activating KRAS mutation (G12D) and the patient was started on first-line treatment with Reolysin in combination with gemcitabine in March 2012. Stable disease was achieved with significant improvement in cancer-related pain. Following 25 cycles of treatment over 23 months, a second biopsy was collected and immunohistochemical analyses revealed the presence of reovirus replication and induction of the ER stress-related gene GRP78/BIP and the pro-apoptotic protein NOXA. Importantly, co-localization of reoviral protein and active caspase-3 was also observed in the biopsy specimen. CONCLUSION: This is the first report of reoviral protein detection in primary tumor biopsies taken from a pancreatic cancer patient receiving intravenous Reolysin therapy. The accumulation of reoviral protein was associated with ER stress induction and caspase-3 processing suggesting that Reolysin and gemcitabine treatment exhibited direct pro-apoptotic activity against the tumor.

EBV-associated lymphoepithelioma-like carcinoma of the pancreas: Case report with targeted sequencing analysis.

Lymphoepithelioma-like carcinomas are distinctive epithelial derived malignant neoplasms that have a syncytial growth pattern and lymphoid stroma. The majority of tumors with this appearance are Epstein Barr virus (EBV)-associated. We report a patient with a clinical presentation concerning for lymphoma who was diagnosed with an EBV-associated pancreatic carcinoma with a lymphoepithelioma-like pattern. Targeted sequencing analysis showed a molecular profile distinct from conventional ductal adenocarcinoma of the pancreas.

Is previous exposure to hepatitis B a risk factor for pancreatic cancer or hepatocellular carcinoma?

GOALS: We evaluated whether prior infection with the hepatitis B virus (HBV) influences the development of pancreatic cancer or hepatocellular carcinoma (HCC). BACKGROUND: Prior infection with HBV may predispose patients to developing pancreatic cancer or HCC. STUDY: We conducted a retrospective cohort study using administrative data from an integrated health care system. We identified all patients who had HBV testing over a 13-year period. These patients were divided into 1 of 3 cohorts based on HBV status: negative infection (n=28,719), previous exposure (n=5141), or active infection (n=404). Pancreatic cancer and HCC data were obtained from pathology reports in the health system's cancer registry. RESULTS: In a multivariable model, age [hazards ratio (HR), 1.08; confidence interval (CI), 1.06-1.09; P<0.001)] and presence of diabetes (HR, 1.88; CI, 1.27-2.80; P=0.002) were identified to have significant influence on pancreatic cancer development, whereas previous HBV exposure did not have a significant influence (HR, 1.41; CI, 0.88-2.27; P=0.16). In a separate multivariable model, male sex (HR, 2.05; CI, 1.35-3.11; P<0.001), age (HR, 1.08; CI, 1.06-1.09; P<0.001), being hepatitis C positive (HR, 5.40; CI, 3.51-8.33; P<0.001), and presence of cirrhosis (HR, 27.84; CI, 17.43-44.46, P<0.001) were all significant predictors of HCC. However, previous HBV exposure was not associated with HCC development (HR, 1.03; CI, 0.68-1.56; P=0.88). CONCLUSIONS: Data from this study indicate that previous HBV exposure is not a risk factor for the development of either pancreatic cancer or HCC.

Immunotherapeutic and oncolytic viral therapeutic strategies in pancreatic cancer.

Pancreatic adenocarcinoma is an aggressive disease with dismal outcomes despite recent advances using combination chemotherapeutic regimens. The lack of an adequate immune response to malignant cells has been identified as a factor associated with tumor aggressiveness and refractoriness to systemic treatment. Preclinical and early clinical studies have identified numerous immunotherapeutic and oncolytic viral therapeutic strategies aimed towards amplifying the immune reaction to pancreatic cancer and have established encouraging results. Promising antitumor efficacy has been observed both in vitro and in vivo with many of these approaches. These novel applications have also led to improved understanding of the process of pancreatic tumor growth and invasion, knowledge of the tumor microenvironment and have pioneered further investigations of similar therapies. Here we review both immunotherapeutic and oncolytic viral therapeutic strategies in pancreatic cancer.

[Association between hepatitis B virus infection and risk of pancreatic cancer: a meta-analysis].

OBJECTIVE: To investigate the relationship between hepatitis B virus (HBV) infection and risk of pancreatic cancer. METHODS: Various English and Chinese language literature databases, including PubMed, Web of Knowledge, Embase, Cochrane Library and the Chinese National Knowledge Infrastructure, were searched for case-control studies comparing rates of HBV infection and pancreatic cancer. The RevMan meta analysis software, version 5.0, was used to perform the meta-analysis of the 6 included studies. RESULTS: Compared with the control group, the pancreatic cancer group had a significantly higher rate of positivity for hepatitis B surface antigen (HBsAg) (8.87% vs.5.86%, odds ratio (OR) =1.24, 95% confidence interval (CI):1.06 to 1.47, P =0.009) and a lower rate of patients never exposed to HBV (defined as HBsAg(-)/hepatitis B core antibody (anti-HBc)(-) (69.4% vs.77.1%, OR =0.68, 95% CI:0.51 to 0.92, P =0.01). There was no significant difference between the two groups in the rate of hepatitis B e antigen positivity (P =0.55). CONCLUSION: HBV-infected patients with HBsAg(+) status are at greater risk of developing pancreatic cancer; however, since most of the research studies evaluated were conducted in Asians, the generalizability of this conclusion is unknown.

Conditionally replicative adenoviral vectors for imaging the effect of chemotherapy on pancreatic cancer cells.

Pancreatic cancer has a poor prognosis after complete macroscopic resection combined with chemotherapy. Even after neoadjuvant chemotherapy, R0 resection is often not possible. Moreover, current imaging techniques cannot reliably distinguish viable cancer cells from scar tissue at the resectional margin. We investigated the use of a conditionally replicative adenovirus (CRAd), Ad5/3Cox2CRAd-ΔE3ADP-Luc, for imaging the effects of chemotherapy. The CRAd infectivity of pancreatic cancer cells was enhanced by a chimeric Ad5/3 fiber, E1A expression was under the control of the Cox2 promoter, and the luciferase gene was inserted adjacent to the adenovirus death protein (ADP) gene. Subcutaneous xenografts of the pancreatic cancer cell line MiaPaCa-2 were established in 24 BALB/c nu/nu mice. When xenografts reached a diameter of 4-6 mm (day 1), the mice were injected i.p. with either PBS (group A; n = 12) or 1000 mg/kg gemcitabine (group B; n = 12), weekly. On days 19, 26, 33, and 40, CRAd were injected intratumorally into three mice in groups A and B. Bioluminescence was imaged 72 h after CRAd injection, and gross tumor volumes were measured then tumors were removed for ex vivo histopathology using H&E and Ki-67 staining. Correlations between gross tumor volume, pathological evaluation of the percentage of viable tumor area, and CRAd bioluminescence were analyzed. Bioluminescence correlated closely with the percentage of viable tumor area (R = 0.96), but not with gross tumor volume (R = 0.31). Therefore, CRAds might be reliable imaging tools for monitoring chemotherapy in pancreatic cancer, and could improve our ability to distinguish viable tumor cells from scar tissue.

HBV infection increases the risk of pancreatic cancer: a meta-analysis.

BACKGROUND: Hepatitis B virus (HBV) infection is reported to be associated with an increased risk of pancreatic cancer (PaC), but it remains controversial whether this is a causal relationship. In addition, it is unclear whether the status of HBV infection also affects PaC risk. Therefore, we conducted a meta-analysis to more closely examine the association between HBV infection and PaC. METHOD: The studies included in the meta-analysis were identified and retrieved from PubMed and several other databases. The literature search was conducted up until August 2012. We adopted the Cochrane Collaboration's RevMan 5.1 in a combined analysis of pooled relative risk (RR) with their corresponding 95 % confidence intervals (CIs) using a random-effects and a fixed-effects model. RESULTS: Nine studies including 6 case-control and 3 cohort studies met eligibility criteria. The meta-analysis showed that the PaC risk was positively correlated with HBV infection when comparing with 'never exposed to HBV' subgroup, the pooled RR was 1.39 (95 % CI 1.22-1.59, p < 0.00001) in chronic HBV carriers, 1.41 (95 % CI 1.06-1.87, p = 0.02) in past exposure to HBV, and 3.83 (95 % CI 1.76-8.36, p = 0.0007) in active HBV infection. Using a stratified analysis, we also found that the risk of PaC was independent of smoking, alcohol drinking, and diabetes. CONCLUSION: Findings from this meta-analysis strongly support that HBV infection is associated with an increased risk of PaC.

The status of HBV infection influences metastatic pattern and survival in Chinese patients with pancreatic cancer.

BACKGROUND: It has been proved that hepatitis B virus (HBV) infection alters the metastatic pattern and affects survival in colorectal cancer (CRC) and hepatocellular carcinoma (HCC), while the influence of HBV infection on metastatic pattern and survival in patients with pancreatic cancer (PC) has not been investigated yet. METHODS: We conducted an investigation to evaluate the impact of HBV infection on metastatic pattern and overall survival in PC. We collected the data of 460 PC patients treated in our hospital from 1999 to 2010. Serum HBV markers were tested with enzyme-linked immunosorbent assay. The impact of HBV infection on metastatic pattern and overall survival was analyzed. RESULTS: We found that the incidence of synchronous liver metastasis was significantly higher in patients with HBsAg positive than those with HBsAg negative (46.0% vs 32.0%, P < 0.05), and higher in chronic HBV infection (CHB) group than both non HBV infection and resolved HBV infection group (61.1% vs 33.9%, P < 0.05, and 61.1% vs 28.7%, P < 0.05, respectively). What's more, Kaplan-Meier analysis showed that CHB, resolved HBV infection and non HBV infection group had significant longer overall survival (OS) compared with inactive HBsAg carriers (IC) group (P=0.037, P=0.009, and P=0.019 respectively). But, in the multivariate analysis, only the CHB and non HBV infection group had significant better overall survival compared with IC group (P=0.010 and P=0.018 respectively). CONCLUSIONS: Our study found that HBV infection increased synchronous liver metastasis rate, and HBV infection status was an independent prognostic factor in PC patients.

Association between hepatitis B or hepatitis C virus infection and risk of pancreatic adenocarcinoma development: a systematic review and meta-analysis.

BACKGROUND: Pancreatic adenocarcinoma (PAC) is an aggressive cancer with a poor prognosis. To date, PAC causes are still largely unknown. Antigens and replicative sequences of oncogenic hepatitis B (HBV) and hepatitis C (HCV) virus were detected in different extra-hepatic tissues, including pancreas. OBJECTIVE: a systematic review and meta-analysis of epidemiological studies assessing PAC risk in patients with HBV/HCV chronic infections. METHODS: In September 2012, we extracted the articles published in Medline, Embase and the Cochrane Library, using the following search terms: "chronic HBV" and "HCV", "hepatitis", "PAC", "risk factors", "epidemiology". Only case/control (C/C), prospective/retrospective cohort studies (PCS/RCS) written in English were collected. RESULTS: four hospital-based C/C studies and one PCS, in HBV-infected patients and two hospital-based C/C studies and one RCS in HCV-infected subjects met inclusion criteria. In these studies HBsAg positivity enhanced significantly PAC risk (RR = 1.18, 95% CI:1.04-1.33), whereas HBeAg positivity (RR = 1.31, 95% CI:0.85-2.02) as well as HBsAg negative/HBcAb positive/HBsAb positive pattern (RR = 1.12, 95% CI:0.78-1.59) and HBsAg negative/HBcAb positive/HBsAb negative pattern (RR = 1.30, 95% CI:0.93-1.84) did not. Relationship between PAC risk and anti-HCV positivity was not significant, although it reached a borderline value (RR = 1.160, 95% CI:0.99-1.3). CONCLUSIONS: HBV/HCV infection may represent a risk factor for PAC, but the small number of available researches, involving mainly populations of Asian ethnicity and the substantial variation between different geographical areas in seroprevalence of HBV/HCV-antigens/antibodies and genotypes are limiting factors to present meta-analysis.

HBV- and HCV-related infections and risk of pancreatic cancer.

Pancreatic carcinoma is one of the most lethal cancers in humans. The poor prognosis of this malignancy depends on several factors, such as: lack of early symptoms, advanced stage at detection, early metastatic spread and no effective systemic treatment. To date, only few risk factors for this malignancy are known; therefore, considerable efforts are required to identify additional causative agents involved in the process of pancreatic carcinogenesis. In the last years, a large series of epidemiological investigations have suggested that both bacteria and viruses may play a important role in the initiation and progression of several animal and human cancers. In particular, some studies have showed that hepatitis B (HBV) and hepatitis C (HCV) viruses, two hepatotropic pathogens with well-known oncogenic properties for liver, may be detected also in extra-hepatic tissues, such as pancreas. The aim of this paper is to briefly report the results of available studies, assessing the possible association between HBV/HCV and pancreatic cancer development as well as to discuss the limiting factors of these researches.

ABO blood group, hepatitis B viral infection and risk of pancreatic cancer.

Little is known about the role of association between ABO blood type and risk of pancreatic cancer develops through effects on hepatitis B viral (HBV) infection. Our study aimed to determine whether joint ABO blood type and HBV infection could increase the risk for pancreatic cancer. A total of 645 patients with pancreatic adenocarcinoma and 711 age- and sex-matched individuals who had nonmalignant diseases treated at the Sun Yat-sen University Cancer Center in China were retrospectively analyzed. Blood samples were tested for ABO blood type and hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), hepatitis B e antigen (HBeAg), hepatitis B e antibody (anti-HBe) and hepatitis B core antibody (anti-HBc). Multivariable unconditional logistic regression analysis was used to estimate adjusted odds ratios [AORs] and 95% confidence interval [CI]. Multivariable analysis with adjustment for risk factors showed that A blood type, HBsAg-positive/anti-HBc-positive, anti-HBs-positive/anti-HBc-positive were significantly associated with pancreatic cancer. The estimated AORs (95% CI) were as follows: A blood type, 1.425 (1.071-1.894), HBsAg-positive/anti-HBc-positive, 1.610 (1.125-2.304), anti-HBs-positive/anti-HBc-positive, 1.526 (1.159-2.011). The effect of A blood type significantly modified the risk of pancreatic cancer among subjects with anti-HBc-positive (AORs = 1.882, 95% CI, 1.284-2.760). In our study, we reported an association between A blood type, infection with HBV and pancreatic cancer risk. Moreover, we found a synergism between A blood type and HBV infection in the development of pancreatic cancer.

A novel genetically modified oncolytic vaccinia virus in experimental models is effective against a wide range of human cancers.

BACKGROUND: Replication-competent oncolytic viruses have shown great promise as a potential cancer treatment. This study aimed to determine whether a novel vaccinia virus, GLV-1h151, with genetic modifications enhancing cancer specificity and enabling virus detection, is effective against a range of human cancers and is safe when administered in preclinical models. METHODS: GLV-1h151 was modified with deletion of thymidine kinase enhancing specificity and insertion of the green fluorescent protein (GFP) gene. The virus was tested in several human cancer cell lines for cytotoxicity including breast, lung, pancreatic, and colorectal. Virus replication was assessed via visualization of GFP expression and bioluminescence, and viral plaque assays. Finally, GLV-1h151 was administered systemically or intratumorally in mice with pancreatic cancer xenografts (PANC-1) to assess virus biodistribution, toxicity, and effect on tumor growth. RESULTS: GLV-1h151 effectively infected, replicated in, and killed several cancer cell types. Detection and visualization of virus replication was successful via fluorescence imaging of GFP expression, which was dose dependent. When administered intravenously or intratumorally in vivo, GLV-1h151 regressed tumor growth (P < 0.001) and displayed a good biosafety profile. GLV-1h151 infection and replication in tumors was successfully visualized via GFP and bioluminescence, with virus presence in tumors confirmed histologically. CONCLUSIONS: GLV-1h151 is effective as an oncolytic agent against a wide range of cancers in cell culture and is effective against pancreatic human xenografts displaying a good biosafety profile and ability to be detected via optical imaging. GLV-1h151 thus adds another potential medium for the killing of cancer and detection of virus in infected tissue.