Simultaneous occurrence of autoimmune hepatitis and autoimmune hemolytic anemia after COVID-19 infection: case report and literature review.

Various autoimmune diseases have been reported to develop as a result of a coronavirus disease 19 (COVID-19) infection. There have been some reports of COVID-19-triggered autoimmune hepatitis and autoimmune hemolytic anemia infection, but none have reported simultaneous onset of these diseases. A 15-year-old girl was admitted to our hospital with severe liver injury and anemia. Three weeks before admission, her father was diagnosed with COVID-19, after which she became aware of a sore throat. Two weeks later, she visited her doctor for malaise. She was referred to our hospital due to severe anemia, elevated hepatobiliary enzymes, and jaundice. A COVID-19 polymerase chain reaction test was positive at the time of referral. She was diagnosed with autoimmune hemolytic anemia based on decreased hemoglobin and haptoglobin, positive direct Coombs test, and increased urinary urobilinogen. Blood tests were positive for antinuclear antibodies, and a liver biopsy revealed interface hepatitis and plasma cell infiltration, consistent with autoimmune hepatitis. Based on these findings, a diagnosis of autoimmune hepatitis and autoimmune hemolytic anemia triggered by COVID-19 infection was made. Steroid therapy was initiated, which resulted in rapid improvement of blood markers and symptoms.

A novel predictive formula for highly accurate discrimination between truly Helicobacter pylori-uninfected and currently infected/spontaneously eradicated individuals for gastric cancer screening.

The ABC classification, which categorizes gastric cancer risk based on serum Helicobacter pylori (H pylori) antibody and pepsinogen levels, has a limitation of potentially misclassifying high-risk individuals as low risk. To overcome the problem, we previously developed a 4-parameter predictive formula (age, serum H pylori antibody, PGI, and PGII) using logistic regression analysis to accurately identify low-risk truly H pylori-uninfected status. Our predictive formula demonstrated superior sensitivity and specificity in distinguishing between low-risk truly uninfected individuals and high-risk currently/spontaneously eradicated status individuals, compared to the modified ABC classification based on latex immunoassay kits (traditional 3-parameter model). This study aimed to revalidate the diagnostic accuracy of the predictive formula in a new and different study population. We applied the predictive formula to the target population and compared the sensitivity and specificity with those of the traditional 3-parameter model. A total of 788 enrollees were analyzed: 703 were classified as truly uninfected, 45 as currently infected, and 40 as spontaneously eradicated according to the results of stool antigen testing and endoscopic findings. The sensitivities and specificities of the predictive formula and the traditional 3-parameter model were 89.5% and 87.1% versus 89.8% and 80.0%, respectively. The specificity of the predictive formula was superior in the 70 to 89 age range and H pylori antibody < 3 U/mL groups. The predictive formula had higher specificity than the traditional 3-parameter model. The results should contribute to efficient gastric cancer screening by predicting H pylori infection status.

Shrinkage of Enlarged Hepatic Nodules by an Embolizing Congenital Extrahepatic Portosystemic Shunt.

A 38-year-old woman was admitted to our university hospital with loss of muscle strength. She was diagnosed with dermatomyositis and underwent contrast-enhanced computed tomography of the entire body to check for malignant tumors. Computed tomography revealed multiple enhanced hepatic nodules and an extrahepatic portosystemic shunt. Although a needle biopsy of the nodule could not diagnose definitive hepatocellular carcinoma, some nodules increased in size after three months. Because of the inconclusive results of the second biopsy, we performed shunt embolization using a vascular plug. After another three months, the hepatic nodules shrank markedly, as expected.

Proton beam therapy for hepatocellular carcinoma with bile duct invasion.

AIM: Hepatocellular carcinoma (HCC) with bile duct invasion (BDI) (BDIHCC) has a poor prognosis. Moreover, due to the paucity of reports, there is no consensus regarding optimal management of this clinical condition yet. The aim of this study was to clarify the efficacy and safety of proton beam therapy (PBT) for BDIHCC. METHODS: Between 2009 and 2018, 15 patients with BDIHCC underwent PBT at our institution. The overall survival (OS), local control (LC), and progression-free survival (PFS) curves were constructed using the Kaplan-Meier method. Toxicities were assessed using the Common Terminology Criteria of Adverse Events version 4.0. RESULTS: The median follow-up time was 23.4 months (range, 7.9-54.3). The median age was 71 years (range, 58-90 years). Many patients were Child A (n = 8, 53.3%) and most had solitary tumors (n = 11, 73.3%). Additionally, most patients had central type BDI (n = 11, 73%). The median tumor size was 4.0 cm (range, 1.5-8.0 cm). The 1-, 2-, and 3-year OS rates were 80.0%, 58.7% and 40.2%, respectively, and the corresponding LC and PFS rates were 93.3%, 93.3%, and 74.7% and 72.7%, 9.7%, and 0.0%, respectively. Acute grade 1/2 dermatitis (n = 7, 46.7%), and grades 2 (n = 1, 6.7%) and 3 (n = 1, 6.7%) cholangitis were observed. Late toxicities such as grade 3 gastric hemorrhage and pleural effusion were observed. No toxicities of grade 4 or higher were observed. CONCLUSIONS: PBT was feasible with tolerable toxicities for the treatment of BDIHCC.

The Optimal Cut-off of the Latex Immunoassay (LZ Test) for Helicobacter pylori Infection Based on the Stool Antigen Test and Helicobacter pylori-associated Gastritis.

Objective Helicobacter pylori antibody kits using the latex immunoassay (LIA) are widely used in Japan. However, the optimal cut-off of the LIA remains unclear. This study clarified the optimal cut-off of the LIA for assessing the current infection status of patients (currently infected, never infected, spontaneously eradicated) in clinical practice. Methods In total, 482 subjects with no history of H. pylori eradication therapy who underwent a medical examination at our hospital were enrolled. The infection status was ascertained using a stool antigen test, and the endoscopic findings of H. pylori-associated gastritis. H. pylori antibody levels were measured using the LIA. Results In total, 414, 38, and 30 subjects were categorized into the never-infected, currently infected, and spontaneously eradicated groups. The optimal cut-off based on receiver operating characteristic curve analysis was 4 U/mL, whereas the area under the curve, sensitivity, and specificity for differentiating never-infected and currently infected subjects were 0.95, 92.1%, and 94.7%, respectively. When applying the cut-off of 4 U/mL to the judgment of current infection in all subjects, the sensitivity and specificity were 92.1% and 92.6%, respectively. Conclusion Our findings suggest that 4 U/mL was the optimal cut-off for differentiating current infection from no prior infection, and the value may be stable because of the exclusion of subjects with spontaneous eradication. The cut-off may be useful in initial screening for current H. pylori infection.

Diagnostic accuracy of the Single-item Measure of Burnout (Japanese version) for identifying medical resident burnout.

Background: Burnout is a psychological syndrome consisting of emotional exhaustion, cynicism, and decreased professional efficacy. The Maslach Burnout Inventory (MBI) is widely used as the standard measure. However, the MBI is lengthy and not free to use, which makes it a less than ideal tool for regularly assessing burnout. The single question burnout measure (SMB) is a novel and simple measure of burnout, which is associated well with emotional exhaustion and has sufficient diagnostic performance for burnout. This study aimed to evaluate the concurrent and convergent validity of the Japanese version of the single-item measure of burnout (SMB-J) compared with the MBI. Methods: Ninety-four medical residents volunteered to complete the MBI-General Survey (MBI-GS) and the SMB-J. We assessed the concurrent (sensitivity and specificity) and convergent validity of the SMB-J compared with the MBI-GS. Results: The sensitivity for identifying burnout using the SMB-J was 53.8%, and the specificity was 88.2%. The area under the receiver operating characteristic curve (AUC) was 0.71. MBI-GS scores on the subscales of Emotional Exhaustion (r = 0.509, p < 0.0001) and Cynicism (r = 0.57, p < 0.0001) strongly correlated with the SMB-J scores. Conclusions: We concluded that for identifying burnout among Japanese medical residents, the psychometric properties of the SMB-J are comparable to those of the original version of the SMB. Although the SMB-J has low sensitivity to detect burnout, it is more convenient to use than the MBI.

Autoimmune hepatitis with history of HCV treatment triggered by COVID-19 vaccination: case report and literature review.

Although vaccines have been effective against the worldwide pandemic of Coronavirus Disease 19 (COVID-19), some case reports have described autoimmune hepatitis triggered by COVID-19 vaccination. Meanwhile, hepatitis C virus (HCV) is known to be related to autoimmune diseases. Here, we report a case of autoimmune hepatitis with history of HCV treatment triggered by COVID-19 vaccination. An 82-year-old woman was referred to our hospital for severe liver injury. She had received a COVID-19 vaccination 7 days prior. She had a history of HCV treatment with direct-acting antivirals 7 years previously. In her blood data, despite HCV antibody positivity, she was negative for HCV RNA by real-time RT-PCR. Anti-nuclear antibody was positive and IgG was elevated. Interface hepatitis and plasma cell infiltration were confirmed pathologically. She was diagnosed as autoimmune hepatitis and her liver injury quickly improved after initiation of steroid administration. This is a first case report of autoimmune hepatitis with history of HCV treatment triggered by COVID-19 vaccination.

Relationship Between Depression and Stress Coping Ability Among Residents in Japan: A Two-Year Longitudinal Study.

BACKGROUND: Depression among medical residents is a critical issue. The early detection of depression and provision of appropriate care is necessary for fostering healthy conditions during clinical training. To investigate whether Sense of Coherence (SOC), an indicator of stress coping ability, could be a predictor of depression 2 years after the start of clinical training, we conducted a national longitudinal study. METHODS: We distributed self-administered questionnaires to residents in 251 postgraduate educational hospitals just before the start of their clinical training. The questionnaire contained the Center for Epidemiologic Studies Depression (CES-D) scale (a screening tool for depression), the SOC scale, and demographic factors. After 2 years, we distributed questionnaires to residents who responded to the first survey. The second questionnaire contained the CES-D scale and questions about working conditions. We categorized respondents into three groups according to their SOC score and analyzed the relationship between SOC groups (low, middle, high) and depressive symptoms on the follow-up survey. RESULTS: In total, 1,738 of 2,935 residents (59.2%) responded to the first survey. Of these, 1,169 residents (67.3%) also responded to the follow-up survey. A total of 169 residents were excluded because they screened positive for depressive symptoms at the time of the first survey. On the follow-up survey, 187 residents (19.5%) had new-onset depressive symptoms: 33.3% in the low SOC group, 18.2% in the middle SOC group, and 11.4% in the high SOC group (P < 0.01). Compared with the high SOC group, the odds ratio for new-onset depressive symptoms in the low SOC group was 2.04 (95% confidence interval, 1.02 - 4.05) after adjusting for demographic factors, baseline CES-D score, and mean working time. CONCLUSIONS: SOC score is significantly associated with future depressive symptoms among residents after 2 years. Residents in the low SOC group had a 2-fold higher risk of future depressive symptoms than those in the high SOC group. The SOC scale might be a useful predictor of future depression and allow for the provision of appropriate support to residents during clinical training.

The relationship between long working hours and depression among first-year residents in Japan.

BACKGROUND: In Japan, some residents develop mental health problems. In previous studies, it was reported that long working hours might be a cause of stress reaction such as depression. There were some reports that compared residents with 80 or more working hours with those with less than 80 working hours. However, many residents are practically detained for extra-long time, designated as 100 h or more per week, for medical practice, training, self-study, etc. There have been few reports on extra-long hours of work. This study evaluated the working environment and the amount of stress experienced by first-year residents, and examined the relationship between long working hours and depression, especially in the group of extra-long working hours. METHODS: The study included 1241 first-year residents employed at 250 training hospitals in 2011. A self-report questionnaire was administered at the beginning of the residency and 3 months later to collect data on demographics, depressive symptoms, and training conditions (e.g., duration of work, sleep, disposable time, and night shift). Depressive symptoms were rated using the Center for Epidemiologic Studies Depression Scale. RESULTS: The mean duration of work per week was 79.4 h, with 97 residents (7.8%) working 100 h or more. At 3 months, clinically significant depressive symptoms were reported by 45.5% of residents working 100 or more h per week, which proportion was significantly greater than that for respondents working less than 60 h (P < 0.001). Multivariate logistic regression analysis showed that a working week of 80 to 99.9 h was associated with a 2.83 fold higher risk and 100 h or more was associated with a 6.96-fold higher risk of developing depressive symptoms compared with a working week of less than 60 h. CONCLUSION: Working excessively long hours was significantly associated with development of depressive symptoms. Proper management of resident physicians' working hours is critical to maintaining their physical and mental health and to improve the quality of care they provide.

Stress Factors Associated With Burnout Among Attending Physicians: A Cross-Sectional Study.

BACKGROUND: Burnout in attending physicians is a crucial issue that may negatively impact patient outcomes, as well as affect the quality of training provided to residents. To investigate the association between burnout and stress-coping ability, we conducted a cross-sectional study of attending physicians. METHODS: From April 2013 to March 2014, we distributed an anonymous, self-administered questionnaire to 1,897 attending physicians who attended teaching-related training sessions and workshops. The questionnaire included the Maslach Burnout Inventory General Survey (MBI-GS, Japanese version) to evaluate burnout; the sense of coherence scale (SOC, Japanese version) to measure stress-coping ability, with higher scores indicating higher stress-coping ability; the Brief Scales for Job Stress (BSJS) to assess stress and buffering factors; demographic factors; mean weekly working hours; and factors related to instructing residents. The MBI-GS was used to determine the presence of physician burnout. Subjects were divided into tertiles based on SOC scores. We conducted logistic regression analysis of burnout using the following independent variables: physician experience, sex, mean weekly working hours, SOC group, mental workload, and reward from work. RESULTS: Of the 1,543 (81.3%) attending physicians who responded, 376 did not meet the inclusion criteria and 106 had missing data, thus 1,061 (55.9%) were analyzed. The prevalence of burnout was 17.2%. Physicians with burnout had significantly fewer years of experience as a doctor (P < 0.01), were more likely to be female (P < 0.01), worked more hours per week (P < 0.01), and had a lower SOC score (P < 0.01) than physicians without burnout. On the BSJS, the mean score of all stress factors was higher and that of buffering factors was lower in physicians with burnout (P < 0.01). The percentages of physicians with burnout were 35.7%, 12.8%, and 3.2% in the low, middle, and high SOC groups, respectively (P < 0.01). Using the high SOC group as a reference, the adjusted odds ratio for burnout in the low SOC group was 4.7 (95% confidence interval: 2.31 - 9.63) (P < 0.01). CONCLUSIONS: In this study, burnout among attending physicians was significantly associated with SOC scores after adjustment for stress factors and buffering factors.

Recovery from a depressive episode during postgraduate residency training is associated with senior doctors' support.

Background: Depression among doctors in residency training can have significant impacts on the health of the residents and on patient safety. This study aimed to investigate factors associated with recovery from a depressive episode experienced during postgraduate residency training. Methods: A questionnaire was administered to 2935 first-year residents at the beginning of residency training in 2011; follow-up surveys were conducted after 3 months and at the end of the training in 2013. The questionnaire included the Center for Epidemiologic Studies Depression Scale and the Senior Doctor's Support Scale (SDSS). Logistic regression was used to identify associations between factors that may have been related to recovery from depressive episodes. Results: A total 182 residents experienced a depressive episode in the 3 months after starting residency training. When reassessed at the end of the 2-year training, 102 (56%) residents had recovered from the episode and 80 (44%) had not. Increased odds of recovery were associated with a middle or high score on the SDSS (middle score odds ratios [OR] 4.45, 95% confidence interval [CI] 1.0-18.0, P = .04; and high score OR 5.70, 95% CI 1.4-23.4, P = .02). Conclusions: Support from senior doctors should be enhanced to optimize recovery from depressive episodes experienced after the start of residency training.

Oncolytic Virotherapy and Gene Therapy Strategies for Hepatobiliary Cancers.

Advanced liver cancers and biliary cancers represent diseases with dismal prognosis because of frequent local invasion and metastasis. Effective therapeutic agents for these cancers have not been established. Oncolytic viruses (OVs) constitute a novel class of promising, selective anticancer agents and recent studies have elucidated their unique features. Moreover, clinical trials are demonstrating promising results. Numerous OVs are being tested in preclinical models of hepatocellular carcinoma (HCC). The lead agent Pexa-Vec (pexastimogene devacirepvec, JX-594), a recombinant Wyeth strain vaccinia virus, has demonstrated preliminary evidence of safety and efficacy for HCC in clinical trials. Few other OVs have entered clinical testing. Relatively few preclinical studies and clinical trials exist for biliary cancers. In this review, we introduce various approaches using OVs to treat the intractable hepatobiliary cancers.

Can we predict future depression in residents before the start of clinical training?

CONTEXT: Depression among medical residents is a very serious problem. It is, however, very difficult to detect signs of depression early, despite the severity and frequency of depression. We designed a nationwide longitudinal study to investigate whether the Sense of Coherence (SOC) Scale, an indicator of ability to cope with stress, could predict future depressive symptoms among medical residents. METHODS: We distributed self-administered questionnaires to first-year residents in 251 postgraduate education hospitals just before the start of their clinical training. The questionnaire contained the Center for Epidemiologic Studies Depression (CES-D) Scale (a screening tool for depression), the SOC Scale, and items on demographic factors. After 3 months, we again distributed questionnaires to residents who had responded to the first survey. The second questionnaire contained the CES-D Scale and items on the respondents' working conditions. We categorised respondents into three groups according to their SOC scores and analysed the relationships between the three SOC groups (low, middle and high scores) and the occurrence of depressive symptoms at the follow-up survey. RESULTS: In all, 1738 of 2935 residents (59.2%) responded to the first survey. Of these, 1245 residents (71.6%) also responded to the follow-up survey. A total of 189 residents were excluded because they screened positive for depressive symptoms at the first survey. Data for a further 36 were excluded because they were incomplete. At the follow-up survey, 238 of the remaining 1020 residents (23.3%) had new-onset depressive symptoms. These included 61 (41.2%) respondents in the low SOC group, 159 (22.3%) in the middle SOC group, and 18 (11.3%) in the high SOC group (p < 0.01). The odds ratio of the low SOC group for new-onset depressive symptoms, adjusted for demographic factors, baseline CES-D score and mean working time, was 3.11 (95% confidence interval 1.48-6.53), using the high SOC group as the reference. CONCLUSIONS: The SOC score was significantly related to future depressive symptoms among medical residents. The SOC Scale might be a useful and easy-to-use predictor of future depression.

Cyclophosphamide enhances antitumor efficacy of oncolytic adenovirus expressing uracil phosphoribosyltransferase (UPRT) in immunocompetent Syrian hamsters.

Oncolytic viruses (OVs) are novel cancer therapeutics with great promise, but host antiviral immunity represents the hurdle for their efficacy. Immunosuppression by cyclophosphamide (CP) has thus been shown to enhance the oncolytic efficacy of many OVs, but its effects on OVs armed with therapeutic genes remain unknown. We have previously reported on the efficacy of AxE1CAUP, an oncolytic adenovirus (OAd) expressing uracil phosphoribosyltransferase (UPRT), an enzyme that markedly enhanced the toxicity of 5-fluorouracil (5-FU), in immunodeficient, Ad-nonpermissive nude mice. Here we explored the efficacy and safety of intratumoral (i.t.) AxE1CAUP/5-FU therapy and of its combination with CP for syngenic HaP-T1 pancreatic cancers in immunocompetent, Ad-permissive Syrian hamsters. AxE1CAUP infected, replicated, expressed UPRT, and increased the sensitivity to 5-FU in HaP-T1 cells in vitro. I.t. AxE1CAUP/5-FU treatment inhibited the growth of subcutaneous HaP-T1 allografts. The combination with high-dose CP inhibited serum Ad-neutralizing antibody formation, increased intratumoral AxE1CAUP replication and UPRT expression, and resulted in further enhanced therapeutic effects with 5-FU. Neither body weight nor histology of the liver and lung changed during these treatments. A clinically-approved, intermediate-dose CP also enhanced the efficacy of i.t. AxE1CAUP/5-FU treatment in these hamsters, which was not affected by preexisting immunity to the vector. These data demonstrate the excellent antitumor efficacy and safety of an OAd armed with a suicide gene in combination with CP for treating syngenic tumors in immunocompetent, Ad-permissive animals, indicating the efficacy of CP in overcoming the hurdle of antiviral immunity for effective OV-mediated gene therapy.

EpCAM- and EGFR-targeted selective gene therapy for biliary cancers using Z33-fiber-modified adenovirus.

A critical issue in adenovirus (Ad)-based cancer gene therapy is to improve the specificity of gene delivery to cancer cells for better efficacy and safety. We explored methods of retargeting Ad vectors for selective gene therapy of human biliary cancers using the Ad incorporating an IgG Fc-binding motif (Z33) from the Staphylococcus protein A (Ad-FZ33) combined with tumor-specific antibodies. Flow cytometry analysis revealed high-expression levels of epithelial cell adhesion molecule (EpCAM) and epidermal growth factor receptor (EGFR) on human biliary cancer cells. Ad-FZ33 expressing LacZ combined with antibodies against EpCAM or EGFR, followed by ß-gal assay, demonstrated highly efficient gene transduction in these biliary cancer cells, compared to the treatment with control antibody or without antibody. Ad-FZ33 expressing uracil phosphoribosyl transferase (UPRT), an enzyme which greatly enhances the toxicity of 5-fluorouracil (FU), combined with antibodies against EpCAM or EGFR, remarkably enhanced the sensitivity of biliary cancer cells to 5-FU. By contrast, the treatment did not affect the 5-FU sensitivity of the cells not expressing EpCAM or EGFR including normal hepatocytes. Finally, treatments with the UPRT-expressing Ad-FZ33 with antibodies against EpCAM or EGFR, followed by 5-FU administration, significantly suppressed the growth of biliary cancer xenografts in nude mice. These results indicate that the gene therapy mediated by the Z33 fiber modified Ad with anti-EpCAM or anti-EGFR antibodies offers a potentially effective therapeutic modality against biliary cancers.

E1A, E1B double-restricted adenovirus with RGD-fiber modification exhibits enhanced oncolysis for CAR-deficient biliary cancers.

PURPOSE: Cancers of biliary system represent highly malignant diseases of dismal prognosis. We have previously introduced AxdAdB3, an E1A, E1B double-restricted oncolytic adenovirus, which showed excellent oncolytic efficacy for approximately half of the biliary cancer lines with an enhanced safety to normal cells. The purpose of this study was to evaluate whether RGD-fiber modification (AxdAdB3-F/RGD), which enables integrin-dependent infection, can improve the infectivity and efficacy of AxdAdB3 for biliary cancers. EXPERIMENTAL DESIGN: Expressions of adenoviral receptors, coxsackievirus adenovirus receptor (CAR) and integrins (alpha(v)beta(3) and alpha(v)beta(5)), were compared with the level of infectivity of LacZ-expressing replication-defective adenoviruses with wild-type fibers or RGD-modified fibers in a panel of biliary cancer cell lines in vitro. Viral replication and cytotoxicity in vitro of AxdAdB3-F/RGD, a novel E1A, E1B double-restricted replication-selective adenovirus with RGD-modified fibers, were compared with those of its parent virus, AxdAdB3, in various biliary cancer cells and in normal cells. In vivo antitumor effects of these oncolytic viruses were compared in a xenograft tumor model. RESULTS: Expression of CAR significantly correlated with the adenovirus infectivity, whereas integrin alpha(v)beta(5) was abundantly expressed in almost all biliary cancer cells. Whereas AxdAdB3 effectively replicated and lysed only the biliary cancer cells with a preserved expression of CAR, AxdAdB3-F/RGD exhibited efficient replication and potent oncolysis in both CAR-positive and CAR-negative biliary cancer cells. AxdAdB3-F/RGD showed attenuated replication and little cytopathy in human normal cells (i.e., hepatocytes, WI-38 cells) as well as AxdAdB3. Furthermore, in nude mice with s.c. xenografts of CAR-deficient human biliary cancer, i.t. AxdAdB3-F/RGD therapy caused a marked inhibition of tumor growth. CONCLUSIONS: The RGD-fiber modification strategy enhanced the infectivity, replication, and oncolytic effects of the E1A, E1B double-restricted oncolytic adenovirus for CAR-deficient biliary cancers. In addition, it preserved the merit of excellent safety of the double-restricted virus for normal cells. These results suggest a potential use of this agent for the treatment of biliary cancers.

Effective gene therapy of biliary tract cancers by a conditionally replicative adenovirus expressing uracil phosphoribosyltransferase: significance of timing of 5-fluorouracil administration.

In order to enhance the efficacy of conditionally replicating adenoviruses (CRAd) in the treatment of cancers of the biliary tract, we studied the efficacy in vitro and in vivo of AxE1CAUP, a CRAd vector that carries a gene for uracil phosphoribosyltransferase (UPRT), which converts 5-fluorouracil (5-FU) directly to 5-fluorouridine monophosphate and greatly enhances the cytotoxicity of 5-FU. AxE1CAUP replicated and induced an increased UPRT expression in biliary cancer cells more efficiently than AxCAUP, a nonreplicative adenovirus carrying the UPRT gene. Whereas AxCAUP and AxE1AdB, a CRAd without the UPRT gene, modestly increased the sensitivity of BC cells to 5-FU, AxE1CAUP markedly increased the sensitivity, especially when the timing of 5-FU administration was appropriately chosen. AxE1CAUP replicated much less efficiently in normal WI-38 fibroblasts without any change in the sensitivity to 5-FU. In nude mice with s.c. biliary cancer xenografts, i.t. AxE1CAUP/5-FU therapy inhibited tumor growth significantly more strongly than AxCAUP/5-FU or AxE1AdB/5-FU therapy. Furthermore, in mice with peritoneally disseminated biliary cancer, i.p. AxE1CAUP efficiently proliferated in the tumors, decreased the tumor burden, and prolonged the survival of the mice when 5-FU was started 10 or 15 days after the vector inoculation, whereas earlier initiation of 5-FU resulted in early eradication of the vector and no survival benefit. The present study shows that the CRAd expressing UPRT was a more potent sensitizer of biliary cancer to 5-FU, than was a nonreplicative UPRT-encoding vector or a CRAd without UPRT gene, even at a lower dose of the vector, and that timing of 5-FU administration was a key factor to maximize the efficacy. This gene therapy with appropriately timed administration of 5-FU should be useful in overcoming the resistance of biliary cancers to 5-FU.

E1A, E1B double-restricted adenovirus for oncolytic gene therapy of gallbladder cancer.

New treatments, such as gene therapy, are necessary for advanced gallbladder cancer (GBC), but little has been studied. Recent studies have introduced mutant adenoviruses (Ads) with either defective E1B-55kD or mutated E1A, focusing on tumor-specific replication, and the results have been promising. To enhance the safety of this approach, we constructed AxdAdB-3, a double-restricted Ad with a mutant E1A and E1B-55kD deletion. We studied the effects of this Ad in vitro and in vivo on GBC, as well as its safety for normal human cells. We compared the replication and cytopathic effects of AxdAdB-3 in several lines of GBC and primary normal cells with those of wild-type Ad or of AxE1AdB, an E1B-55kD-deleted Ad. The efficacy in vivo was examined in nude mice with s.c. implanted or i.p. disseminated GBC. AxdAdB-3 replicated in and caused oncolysis of GBC cell lines (TGBC-44TKB and Mz-ChA2) as efficiently as wild-type Ad or AxE1AdB in vitro. By contrast, AxdAdB-3 replicated much less effectively in primary normal cells (e.g., epithelial cells, endothelial cells, and hepatocytes) than in GBC cells and had only mild cytopathic effects, unlike wild-type Ad. Furthermore, cytotoxicity of AxdAdB-3 in normal cells was milder than that of AxE1AdB. AxdAdB-3 significantly (P < 0.01) suppressed the growth of GBC (TGBC-44TKB) xenografts. AxdAdB-3 was also effective in the treatment of mice with peritoneally disseminated GBC (TGBC-44TKB), demonstrating tumor-selective replication and oncolysis that resulted in significantly (P < 0.05) prolonged survival. The present study shows that the E1 double-restricted Ad effectively and selectively replicates in and causes oncolysis of GBC in vitro and in vivo with reduced negative effects on normal cells, suggesting that this approach could be a promising tool for gene therapy of GBC.