Sheng-Wen Wu

Silibinin inhibits the invasion and migration of renal carcinoma 786-O cells in vitro, inhibits the growth of xenografts in vivo and enhances chemosensitivity to 5-fluorouracil and paclitaxel.

Silibinin is a flavonoid antioxidant that is widely used for its anti‐hepatotoxic properties. It exerts a dose‐dependent inhibition on the invasion and migration of 786‐O renal cell carcinoma (RCC) cells in the absence of cytotoxicity. 786‐O cells were treated with silibinin at various concentrations, up to 50 µM, for a defined period and then subjected to gelatin zymography, casein zymography, and Western blot to investigate the impacts of silibinin on metalloproteinase (MMP) ‐2, ‐9, urokinase plasminogen activator (u‐PA), and MAPK pathway signaling proteins, respectively. The results showed that silibinin decreased MMP‐2, MMP‐9, u‐PA, p‐p38, and p‐Erk1/2 expressions in a concentration‐dependent manner. The reduced expressions of MMP‐2 and u‐PA, as well as inhibition of cell invasion were obtained in the cultures pre‐treated with PD98059 (Erk1/2 inhibitor) and SB203580 (p38 inhibitor). An in vivo anti‐tumor study with a nude mice xenograft model by a subcutaneous inoculation of 786‐O cells demonstrated small solid tumors after eight days following cell inoculation. There was a 70.1% reduction in tumor volume and 69.7% reduction in tumor weight by silibinin feeding on day 44, compared to those of controls. Moreover, combination treatment with silibinin and 5‐fluorouracil, paclitaxel, vinblastine, or RAD‐001 enhanced the chemosensitivity of 5‐fluorouracil and paclitaxel. In conclusion, silibinin inhibits the invasion and migration of 786‐O cells in vitro, inhibits the growth of xenografts in vivo, and enhances chemosensitivity to 5‐fluorouracil and paclitaxel.

The effect of low-dose cidofovir on the long-term outcome of polyomavirus-associated nephropathy in renal transplant recipients

BACKGROUND Polyomavirus-associated nephropathy (PVAN) has an unfavourable impact on graft survival. The cornerstone of therapy is early reduction of immunosuppressive medications; however, the rate of graft failure is still high. Antiviral drugs, such as cidofovir, are thought to have therapeutic effects, but the benefits of cidofovir in retarding the deterioration of PVAN are still a controversial issue. METHODS Fourteen renal kidney recipients were diagnosed to have biopsy-proven PVAN between 2001 and 2006 in Chung-Shan Medical University Center with nearly 600 renal transplant recipients. After the diagnosis of PVAN, all patients were treated with a reduction of their original immunosuppressive medications with/without converting tacrolimus to cyclosporine. Eight of the 14 patients agreed to receive low-dose cidofovir (0.5 mg/kg) every 2 weeks for a total of six doses. RESULTS During 30 +/- 18 months of follow-up, three (37%) patients in the cidofovir-treated and three (50%) patients in the non-cidofovir-treated group experienced graft loss (P = 0.64). The rejection rate before PVAN diagnosis or other baseline characteristics of the patients between two groups were not significantly different. The long-term survival rate to graft loss and major graft functional decline with Kaplan-Meier analysis between the two groups were not significantly different (P = 0.898 and P = 0.243). In all demographic and clinical characteristics, we found that there was a tendency towards long-term major graft functional decline in the patients with acute rejection prior to PVAN diagnosis (P = 0.04). CONCLUSIONS We concluded that (1) there was no obvious effect of low-dose cidofovir on long-term graft survival in patients with PVAN, and (2) acute rejection prior to PVAN diagnosis was a potential risk factor for poorer long-term graft outcome.

The suppressive effect of Rho kinase inhibitor, Y-27632, on oncogenic Ras/RhoA induced invasion/migration of human bladder cancer TSGH cells.

Urothelial cell carcinoma is the most common type of malignancy found in long-term dialysis patients and kidney transplant recipients in Taiwan. Surgical specimens of tumorous and non-tumorous bladder tissues were collected from 12 patients with bladder cancer. Increased expressions of Ras, RhoA, Akt, PI-3K were demonstrated in the tumors as compared to adjacent control tissues. To understand the impact of Ras over-expression on bladder cancer progression, human bladder cancer TSGH 8301 cells were transfected with Ras DNA. The Ras-transfected cells were then treated with either a PI-3K inhibitor (wortmannin) or Rho kinase inhibitor (Y-27632) and the expressions of Ras, PI-3K, Akt, NF-kappaB, and RhoA were analyzed. Fluorescent phalloidin staining demonstrated more intense F-actin staining in the Ras over-expressed cells than in the control cells, and the intensity of F-actin was inhibited by Y-27632. A gelatin zymography study demonstrated that the MMP-2 and MMP-9 expressions of the Ras-transfected cells were enhanced, and Y-27632 treatment reduced the levels of MMP-2 and MMP-9. Similarly, a wound healing assay revealed that the ability of cell migration was markedly increased by Ras transfection and the healing rate after treatment of Y-27632 was delayed. Our results provide evidence that Ras-induced RhoA and NF-kappaB activation was involved in the invasion/migration of bladder cancer. Through Ras and/or RhoA inhibition, there might be an opportunity for new therapeutic interventions in bladder cancer.

Plasminogen activator inhibitor-1 5G/5G genotype is a protecting factor preventing posttransplant diabetes mellitus.

OBJECTIVE Plasminogen activator inhibitor 1 (PAI-1) is thought to play a role in the pathogenesis of obesity and insulin resistance. A connection between gestational diabetes mellitus and the functional -675 PAI-1 genotype has been reported. Therefore, we examined the role of the PAI-1 gene polymorphism in kidney transplant recipients. METHODS A total of 376 kidney transplant recipients were prospectively screened for posttransplant diabetes mellitus (PTDM). Eighty-one (21.5%) patients were diagnosed with PTDM and the other 295 patients were non-diabetic following kidney transplantation. DNA samples were isolated from the sera and analyzed for the functional -675 4G/5G promoter polymorphisms of the PAI-1 gene. RESULTS Kidney transplant recipients with PTDM were significantly associated with tacrolimus use (p=0.03), older age (p=0.036), and higher body mass index (p=0.001). The genotype distribution was significantly different between the patients with PTDM (genotype 4G/4G:4G/5G:5G/5G=33.3%:60.5%:6.2%) and those without PTDM (genotype 4G/4G:4G/5G:5G/5G=36.9%:44.1%:19.0%) (p=0.018). Patients with homozygosity for 5G had a significantly lower rate of PTDM (aOR, 0.286, p=0.022) and higher cumulative event-free probability of time to PTDM (log rank test, p=0.0058). CONCLUSION Homozygosity for the 5G allele of the PAI-1 gene constitutes a protecting factor for the development of PTDM. Our findings are similar to a previous study on gestational diabetes mellitus, and strongly support a possible genetic role of PAI-1 in the development of PTDM.

Community-acquired urinary tract infection in kidney transplantation: risk factors for bacteremia and recurrent infection.

BACKGROUND/PURPOSE Urinary tract infection (UTI) is the most common type of infectious complication among kidney transplant patients. However, the antibiotic susceptibility of causative microorganisms and risk factors for concomitant bacteremia and recurrent infection are rarely discussed. METHODS This was a retrospective cohort review of kidney transplant recipients who had received follow-up in the past 10 years at the Chung-Shan Medical University (Taichung, Taiwan). Only community-acquired and symptomatic UTIs were included in this study. RESULTS During the 53 ± 22 months of follow-up, 99 patients developed 167 episodes of UTI. Forty-two (25%) episodes had concomitant bacteremia. Escherichia coli was the most common causative microorganism, and strains with resistance to multiple commonly used empirical antibiotics began to emerge. The independent risk factors for UTI with concomitant bacteremia in multivariate analysis were immunosuppression with tacrolimus (adjusted odds ratio [AOR] 3.17; 95% confidence interval [CI] 1.29-7.75; P = 0.011) and baseline serum creatinine level >1.3 mg/dL before first UTI (AOR 2.55; 95% CI 1.02-6.36; P = 0.045). However, there were no factors that were significantly associated with recurrent infection. CONCLUSION From this study, we found that E coli tends to have resistance to commonly used empirical antibiotics in this modern era and that patients who use the immunosuppressant tacrolimus and have baseline serum creatinine level >1.3 mg/dL before their first UTI have a tendency to suffer from concomitant bacteremia and even sepsis.

Early Diagnosis of Polyomavirus Type BK Infection in Tailoring Immunosuppression for Kidney Transplant Patients: Screening With Urine Qualitative Polymerase Chain Reaction Assay

Polyomavirus type BK (BKV) nephropathy is increasingly a significant cause of graft dysfunction and even failure. Early diagnosis followed by reduction of immunosuppression has been associated with an improved prognosis. We screened 250 patients with the urine qualitative polymerase chain reaction (PCR) for BKV DNA. We followed with blood BKV PCR if the urine screen was positive and then reduced immunosuppression in viremic patients. One hundred ninety-nine patients (80%) had no viuria; 43 (17%) viuria; and 8 (3%) both viuria and viremia. Graft biopsy performed in three patients (1%) with viremia and impaired graft function all revealed BKV nephropathy. After 6 months of follow-up, seven out of eight viremic patients (88%) had negative repeat blood PCR and stabilized graft function. An early diagnosis of BKV infection with reduction of immunosuppression may reverse viremia and retard progression of BKV nephropathy. BKV screening by PCR assays should be considered in kidney transplant recipients, especially those with impaired graft function.

Association between interleukin 23 receptor polymorphism and kidney transplant outcomes: a 10-year Taiwan cohort study.

OBJECTIVE Interleukin 23 receptor (IL-23R) plays a role in the pathogenesis of multiple autoimmune processes. The relationship between allograft outcomes and the IL-23Rvariant genotypes has not been reported on previously. Therefore, we examined the relationship between this genetic polymorphism and kidney transplant outcomes. METHODS This is an observational cohort study and 422 renal transplant recipients (RTRs) were enrolled. Polymerase chain reaction-restriction fragment length polymorphism was used for the measurement of IL-23R genetic polymorphisms. We used a composite end-point incorporating serum creatinine (SCr) doubling, graft failure and death as the primary outcome. Secondary outcomes included biopsy-proven acute rejection (BPAR), biopsy-proven interstitial fibrosis/tubular atrophy (IF/TA) and individual primary outcome. The risks of developing primary and secondary outcomes were compared between the different IL-23R genotypes and alleles. RESULTS With a mean follow-up of 79.3±28.8 months, 26 patients in the IL-23R genotype AA group and 32 patients in the IL-23R genotype AC/CC group reached the primary outcome (p=0.061). RTRs who carried the IL-23R AC/CC genotype (aHR 1.78; 95% CI. 1.01-3.12; p=0.046) and C allele (aHR 1.48; 95% CI. 0.96-2.28; p=0.075) had a higher risk of developing primary outcome as compared to those with IL-23R AA genotype and A allele, respectively. Moreover, RTRs who carried the IL-23R AC/CC genotype and C allele had a higher risk of developing biopsy-proven IF/TA (p=0.012; p=0.012) and SCr doubling (p=0.024; p=0.042) as compared to those with IL-23R AA genotype and A allele, respectively. The risk of BPAR, graft failure and death between the IL-23R genotypes and alleles were comparable. CONCLUSION IL-23R polymorphism may have a potential immuno-modulating role in long-term allograft outcome.

Glutathione S-transferase gene polymorphisms are not major risks for susceptibility to posttransplantation diabetes mellitus in Taiwan renal transplant recipients.

Glutathione S‐transferase (GST) M1 null genotype has been reported playing a significant role in the diabetes mellitus (DM) susceptibility in Turkish population. We investigated whether the GSTM1, GSTA1, and GSTP1 gene polymorphisms are associated with posttransplantation diabetes mellitus (PTDM) in Taiwan. There were 283 renal transplant recipients (RTRs) enrolled. Polymerase chain reaction–restriction fragment length polymorphism was used for the measurement of GSTA1, M1, and P1 genetic polymorphisms. PTDM was diagnosed according to the American Diabetes Association guidelines. Eight‐five patients (30%) were diagnosed with PTDM. The averaged posttransplant follow‐up period was 77.9 ± 27.2 months. Duration from transplantat to diagnosis of PTDM ranged from 0.2 to 103.1 months (19.2 ± 26.3 months). There were significantly differences between non‐DM and PTDM groups in age (50.6 ± 11.0 vs. 54.6 ± 9.36 years, P = 0.005), BMI (22.4 ± 3.6 vs. 24.3 ± 3.8, P<0.001). The distributions of GSTA1, GSTP1, and GSTM1 genotypes alleles were not significantly different between PTDM and non‐DM group. Patients carrying the different GSTA1, GSTP1, and GSTM1 genetic and allelic polymorphisms had no differences for the development of PTDM. These overall results suggested a lack of strong association with GSTA1, GSTP1, and GSTM1 genetic polymorphisms to the susceptibility of PTDM in Taiwanese RTRs. J. Clin. Lab. Anal. 25:432–435, 2011.

A Salmonella infection complicated with suppurative thyroiditis and ruptured aortic mycotic aneurysm in a renal transplant recipient.

We report a renal transplant recipient who presented with fever and chills for 2 days. The blood and stool cultures revealed the growth of Salmonella enteriditis. A whole-body gallium scan played an important role in the subsequent diagnosis of suppurative thyroiditis. To our knowledge, this is the first report of acute S. enteriditis thyroiditis in a renal transplant recipient. Despite vigorous antibiotic use and a partial thyroidectomy, he experienced recurrent S. enteriditis infection, resulting in a ruptured thoracic mycotic aneurysm 1 month later. Finally the patient was successfully cured with aneurysm resection, in situ reconstruction of the thoracic aorta, and prolonged antibiotics.

Non-Life-Threatening Leukopenia in a Renal Transplant Recipient With Acute Overdose of Mycophenolate Mofetil

Mycophenolate mofetil (MMF) is increasingly used as an immunosuppressant for organ transplantation and for treatment of autoimmune diseases. As yet, the experience with acute overdose of MMF in humans is limited. Herein we have reported a 40-year-old female kidney recipient with moderate leukopenia and lack of gastrointestinal toxicity following ingestion of 25 g MMF, which was confirmed by serum drug levels. We treated the patient with charcoal decontamination and oral cholestyramine. She recovered completely without sequelae.