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Background: To investigate the impact of concurrent chemoradiotherapy (CCRT) on stage IV rectum cancer. Methods: Between 2000 and 2011, 297 consecutive patients diagnosed with stage IV rectum cancer (synchronous metastasis) were enrolled. Cox proportional hazard analyses were used for prognostic factors determination, and the Kaplan-Meier method was used for survival analyses. Propensity scores with the one-to-one nearest-neighbor matching model were used to select matched patients for validation studies. Results: In total, 63 patients received CCRT and 234 did not. The patients in the CCRT group were younger, had more low-lying lesions, and had more T4 lesions, lung metastases, metastasectomies, and oxaliplatin-based upfront chemotherapy. Before propensity-score matching, a younger age (HR = 0.662, P = 0.016), lower carcinoembryonic antigen (CEA) level (≤20 ng/ml) (HR = 0.531, P = 0.001), no metastasectomy (HR = 3.214, P < 0.001), and no CCRT (HR = 1.844, P = 0.019) were independent prognostic factors after controlling for other confounding factors. After matching, only CEA and metastasectomy, but not CCRT, were independent prognostic factors. The survival benefit of CCRT was restricted to patients who undergo subsequent metastasectomy. Conclusions: Upfront CCRT only provided a survival benefit in patients with stage IV rectum cancer who undergo subsequent metastasectomy. [ABSTRACT FROM AUTHOR]

Abstract: While retrovirus vector (RV) is the main virus vector used in human gene therapy trials, the biosafety issues that surround currently used RVs have become a matter of concern. Similar to the insertional mutagenesis in the therapeutic target cells, the generation of replication-competent retrovirus (RCR) must be minimized during the manufacture of the virus vector. This work investigated the kinetics of RV and RCR production in PA317-RCM1 producer cells in static and microcarrier cell culture systems. RCR in the progeny of transduced Mus dunni cells was detected by the PCR method and the titer of RCR was quantified by cell-based S+/L− assay. The specific rates of RCR production in microcarrier cultures were 271–462% higher than those in the static well-plate cultures. Increased medium exchange operations yielded higher specific rates of RCR production in both static and microcarrier cultures. The optimal medium exchange strategy was on an every 2-day schedule, yielding the highest RV/RCR ratio in static culture but not microcarrier culture. Results of this study presented the difficulty for gene therapy processes that together with the product RV also unwanted RCR produced in two different cell culture systems. [Copyright &y& Elsevier]

Abstract: The dihydrofolate reductase (dhfr)/methotrexate (MTX) selection is a common method to conduct gene amplification in stable clones of Chinese hamster ovary (CHO) cells. We previously reported the use of a short hairpin RNA (shRNA) vector targeted to the dhfr gene resulted in improving the intracellular antigen expression in gene-amplified stable CHO cells [Hong, W.W., Wu, S.C., 2007. A novel RNA silencing vector to improve antigen expression and stability in Chinese hamster ovary cells. Vaccine 25 (20), 4103–4111]. Here we investigated the use of the dhfr-targeted shRNA vector for immunoglobulin G (IgG) expression in gene-amplified stable CHO cells. With the use of the dhfr-targeted shRNA vector, the gene-amplified CHO/dhFr− cells were found to increase IgG expression at 1.0μM MTX by more than 100% and to improve the genomic stability of IgG expression in MTX-free cultures by approximately 30%. The use of the dhfr-targeted shRNA vector can enhance the IgG expression in the gene-amplified stable CHO cells and uphold the IgG expression in MTX-free cultures. Utilizing the dhfr-targeted shRNA vector may provide an alternative way to maneuver CHO cell factories for IgG production in cultures. [Copyright &y& Elsevier]

Abstract: Lamivudine has demonstrated efficacy in the treatment and prevention of hepatitis B virus (HBV) reactivation after hematopoietic stem cell transplantation (HSCT). However, most of these studies involved short durations of prophylaxis, so there is significant concern regarding lamivudine resistance in these patients. Between March 1984 and November 2002, 71 HBV surface antigen–positive HSCT recipients, including a subgroup of 16 who received pretransplantation lamivudine therapy, which was continued into the posttransplantation period to prevent reactivation hepatitis, were enrolled onto our study. The efficacy of lamivudine therapy was first evaluated for the subgroup of 16 patients in terms of treatment response, lamivudine resistance, and viral recurrence after discontinuation by using virologic assays. Efficacy was then evaluated for all patients in terms of the hazards of lamivudine therapy for reactivation hepatitis after transplantation. During a median lamivudine therapy period of 73 weeks (range, 19-153 weeks), the initial response showed a median reduction of 2.54 log10 in serum HBV DNA (−0.28 to 6.72 range). Lamivudine-resistant mutations were detected in 10 (63%) of 16 patients during therapy, and 1 (12%) of 16 patients finally developed a viral breakthrough. At a median follow-up of 30 months after discontinuation, 3 (27%) of 11 cases had recurrence of HBV infection. Despite the emergence of the mutations, no deaths were due to HBV reactivation or severe cases of hepatitis. In the Cox proportion regression model regarding reactivation hepatitis after transplantation of all enrolled patients, lamivudine therapy was found to be the only favorable factor for the event, with a hazard ratio of 0.122 (95% confidence interval, 0.016-0.908; P = .040). In conclusion, extended lamivudine therapy is safe and effective for the prevention of HBV reactivation in an HSCT setting and significantly decreases reactivation hepatitis after transplantation. [Copyright &y& Elsevier]

Objectives. Unusually high incidences of upper urinary tract urothelial carcinoma (UUT-UC) have been reported from the endemic area for “blackfoot disease” of southern Taiwan, and the arsenic-contaminated water was considered to be the reason for this prevalence. In this study, we determined the ratio of UC in different locations, the difference in clinical profiles for UUT-UC and urinary-bladder urothelial carcinoma (UB-UC), and the influence of tumor location on survival in a medical center of northern Taiwan.Methods. A total of 535 patients with pathologically proven UC were reviewed retrospectively in this study, and clinical data were recorded from pathologic and chart reviews. Statistical analyses to determine the association between tumor location and clinical variables, and stratified survival analyses to determine the effect of tumor location on survival were performed.Results. The incidence of UUT-UC was relatively high (the ratio of renal pelvis/ureter/urinary bladder was 1:2.08:6.72), even though most of the patients did not reside in the endemic “blackfoot disease” area. Young age, female sex, higher T stage, and elevated pretreatment serum lactate dehydrogenase and creatinine level were significantly associated with UUT-UC after multivariate logistic regression analysis. Tumor location influenced survival in patients with early-stage disease or favorable prognostic factors.Conclusions. Factors other than arsenic water contamination may contribute to the unusually high incidence of UUT-UC in the non-“blackfoot disease” area in Taiwan. UUT-UC carried a more aggressively clinical behavior than UB-UC; tumor location influences patient survival markedly in patients with early-stage disease or favorable prognostic factors. [Copyright &y& Elsevier]

Objectives. To develop a prognostic-factors-based predictive model for invasive urothelial carcinoma of the urinary bladder derived from statistical comparison of clinical characteristics.Methods. The medical records for patients with invasive urinary bladder urothelial carcinoma were reviewed. Clinical data for age, sex, serum lactate dehydrogenase, creatinine, albumin, alkaline phosphatase, alanine aminotransferase, total bilirubin and hemoglobin levels, white blood cell and platelet counts, positive urine cytology, Eastern Cooperative Oncology Group performance status score, tumor size, histologic grading, T stage, presence of lymph node metastases, squamous differentiation, hydronephrosis, prostatic involvement, Charlson comorbidity index, surgical procedures, and adjuvant chemotherapy status were recorded. Univariate and multivariate analyses were performed to test independent factors for prediction of survival and disease recurrence.Results. After univariate and multivariate analyses, six independent prognostic factors were found: T stage, grading, prostatic involvement, Eastern Cooperative Oncology Group performance status score, and pretreatment serum creatinine and albumin levels. A scoring system was developed on the basis the relative risk associated with the proposed prognostic factors and patients were stratified into three groups according to their scores, with statistically significant prognostic differences revealed for each of the between-group comparisons. Independent factors affecting recurrence-free survival and best predicted disease recurrence were pretreatment serum creatinine, T stage, and surgical procedure.Conclusions. This prognostic-factors-based risk-stratification model for invasive urothelial carcinoma of the urinary bladder may help clinicians predict outcome and select the most appropriate therapeutic modalities. The incidence of recurrent disease is significantly higher for patients with poor renal function before treatment or advanced T stage and those undergoing transurethral tumor resection instead of radical cystectomy. [Copyright &y& Elsevier]