Statin use and risk of kidney cancer: a meta-analysis of observational studies and randomized trials.

AIM: Clinical studies have shown that statin use may modify the risk of kidney cancer. However, these studies yielded different results. To quantify the association between statin use and risk of kidney cancer, we performed a detailed meta-analysis of published studies regarding this subject. METHODS: A literature search was carried out using MEDLINE, EMBASE and the Cochrane database between January 1966 and October 2012. Prior to performing a meta-analysis, the studies were evaluated for publication bias and heterogeneity. Fixed effect and random effect models were used to estimate summary relative risks (RR) and the corresponding 95% confidence intervals (CIs). Subgroup analyses and sensitivity analysis were also performed. RESULTS: A total of 12 (two randomized controlled trials, five cohort, and five case-control) studies contributed to the analysis. There was heterogeneity among the studies but no evidence of publication bias. Pooled results indicated a non-significant decrease of total kidney cancer risk among all statin users (RR = 0.92, 95% CI 0.71, 1.19). Long term statin use did not significantly affect the risk of total kidney cancer (RR = 1.01, 95% CI 0.83, 1.22). In our subgroup analyses, the results were not substantially affected by study design, confounder adjustment and gender. Furthermore, sensitivity analysis confirmed the stability of the results. CONCLUSION: The findings of this meta-analysis suggested that there was no association between statin use and risk of kidney cancer. More studies, especially randomized controlled trials and high quality cohort studies with larger sample size and well controlled confounding factors, are needed to confirm this association in the future.

Preventive effect of phosphodiesterase 5 inhibitor tadalafil on experimental post-pyelonephritic renal injury in rats.

BACKGROUND: To evaluate the effects of Tadalafil, a phosphodiesterase 5 enzyme inhibitor, on Escherichia coli-induced renal damage in an acute pyelonephritis (PN) rat model. METHODS: Experimental PN was induced in 32 Wistar rats, and four groups were formed: group 1 (no treatment), group 2 (antibiotic), group 3 (Tadalafil), and group 4 (antibiotic + Tadalafil). Antibiotic was given on days 3 to 8, and Tadalafil was administered between days 0 and 28 of bacterial inoculation. Half of the rats were killed on the ninth day (early period) and histopathological parameters, immunohistochemical renal fibrosis markers, and oxidant/antioxidant system activities were evaluated. The rest of the rats were killed at the sixth week of the study and evaluated for histopathological parameters and renal fibrosis markers. RESULTS: Inflammatory activity was significantly milder in rats treated with antibiotic + Tadalafil versus no treatment group both in the early and late periods. In the late period, interstitial fibrosis or tubular atrophy was lower in the antibiotic + Tadalafil group versus the no treatment and antibiotic groups, and in Tadalafil versus antibiotic group. Tadalafil administration significantly reduced renal malondialdehyde and nitric oxide levels and enhanced superoxide dismutase and catalase activities. In addition, circulating tumor necrosis factor α, interleukin 1ß was greatly reduced in Tadalafil group versus the no treatment group. CONCLUSIONS: We have provided the first evidence that phosphodiesterase 5 enzyme inhibitor Tadalafil ameliorates circulating inflammatory cytokines, reverses oxidant/antioxidant dysfunction and eventually possesses an overall protective effect on renal tissue from Escherichia coli-induced PN-related kidney injury. Phophodieterase 5 inhibitor might be a novel therapeutic target for PN.

Urinary neutrophil gelatinase-associated lipocalin, a biomarker for systemic inflammatory response syndrome in patients with nephrolithiasis.

BACKGROUND: The objective of this study was to determine the diagnostic value of neutrophil gelatinase-associated lipocalin (NGAL), C-reactive protein (CRP), and procalcitonin (PCT) in the prognosis of patients presenting with the systemic inflammatory response syndrome (SIRS) with nephrolithiasis. METHODS: Urine NGAL protein levels were measured by enzyme-linked immunosorbent assay in 87 patients presenting with nephrolithiasis who were diagnosed as SIRS. Additionally, 52 patients presenting with nephrolithiasis but without urinary tract infection and 30 healthy controls were also included in the study. Levels of serum CRP and PCT were also taken into consideration. RESULTS: Median urinary NGAL levels were significantly increased in the SIRS cohorts compared with nephrolithiasis without urinary tract infection patients (4.28 ng/mL versus 2.69 ng/mL, P < 0.001), and NGAL was markedly elevated even in the early stage of SIRS (3.23 ng/mL versus 2.69 ng/mL, P < 0.001). According to the receiver-operating characteristic analysis, NGAL demonstrated a high diagnostic value compared with either PCT or CRP. In the later stage of SIRS, NGAL remained a highly sensitive (76.8%) and specific (86.5%) diagnostic marker compared with either PCT or CRP. Moreover, the area under the curves of NGAL (0.822) were also superior to those seen in either PCT (0.657) or CRP (0.761). CONCLUSION: Urinary NGAL is a highly sensitive and specific predictor of SIRS for patients presenting with nephrolithiasis. Further study of NGAL as a reliable biomarker of SIRS is required.

Statin use and risk of bladder cancer: a meta-analysis.

PURPOSE: Emerging evidence suggests that statins may decrease the risk of cancers. However, available evidence on bladder cancer is conflicting. To quantify the association between statin use and risk of bladder cancer, we performed a detailed meta-analysis of published studies regarding this subject. METHODS: A literature search was carried out using MEDLINE, EMBASE, and OVID databases between January 1966 and October 2012. Before meta-analysis, between-study heterogeneity and publication bias were assessed using adequate statistical tests. Fixed- and random-effect models were used to estimate summary relative risks (RR) and the corresponding 95 % confidence intervals (CIs). Potential sources of heterogeneity were detected by meta-regression. Subgroup analyses, sensitivity analysis, and cumulative meta-analysis were also performed. RESULTS: A total of 13 (three RCTs, five cohort, and five case-control) studies contributed to the analysis. There was heterogeneity among the studies, but no publication bias. Pooled results indicated a nonsignificant increase in total bladder cancer risk among all statin users [RR = 1.07, 95 % CI (0.95, 1.21)]. Long-term statin use did not significantly affect the risk of total bladder cancer [RR = 1.21, 95 % CI (0.92, 1.59)]. In our subgroup analyses, the results were not substantially affected by study design, region, and confounder adjustment. Furthermore, sensitivity analysis confirmed the stability of the results. CONCLUSIONS: The findings of this meta-analysis suggested that there was no association between statin use and risk of bladder cancer. More studies, especially RCTs, are needed to confirm this association.

A comparative study of thulium laser resection of the prostate and bipolar transurethral plasmakinetic prostatectomy for treating benign prostatic hyperplasia.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Thulium laser is a new generation of surgical laser. It is a minimally invasive technology with several advantages, including rapid vaporization and minimal tissue damage and bleeding. However, details regarding the safety and efficacy of thulium laser in treating BPH remains unknown. We performed a comparative study in 100 patients with BPH of the safety and efficacy of thulium laser resection of the prostate (TMLRP, n = 50) and bipolar transurethral plasmakinetic prostatectomy (TUPKP, n = 50). We found that the efficacy and indications were the same in TMLRP and TUPKP. In TUPKP, the morbidity of urethrostenosis was low, and was nearly bloodless in surgery and had higher safety. Nevertheless, TUPKP is more suitable for patients with larger prostate volume. OBJECTIVE: To compare the safety and short-term efficacy of thulium laser resection of the prostate (TMLRP) and bipolar transurethral plasmakinetic prostatectomy (TUPKP) for the treatment of patients with benign prostatic hyperplasia (BPH). METHODS: A total of 100 patients diagnosed with BPH were randomly divided into two groups, treated with either TMLRP (50, group 1) or TUPKP (50, group 2). There was no significant difference in preoperative variables such as age, prostate volume, prostate-specific antigen (PSA) level, International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax ) and postvoid residual urine volume (PVR) between the two groups. The perioperative parameters and therapeutic effects were recorded and compared between the two groups. RESULTS: There were significant differences in the following parameters between the two groups (TMLRP vs TUPKP [mean ± SD]): operation duration, 61.2 ± 24.2 vs 30.14 ± 15.9 min; catheterization time, 1.8 ± 0.4 vs 3.2 ± 0.6 d; postoperative hospital stay, 3.3 ± 0.8 vs 4.1 ± 1.3 d. The volume of blood loss and postoperative bladder irrigation were significantly lower in TMLRP group than in the TUPKP group. At 1 month after the operation, there were four cases of urethral stricture in the TUPKP group. At 3 months after the operation, IPSS, quality of life (QoL), Qmax and PVR were significantly improved, with no significant difference between the two groups. CONCLUSIONS: TMLRP is superior to TUPKP in terms of safety, blood loss, recovery time and complication rate, and is as efficacious as TUPKP for treating BPH. Operation duration was significantly longer in the TMLRP group than in the TUPKP group.

Novel evidence demonstrates that epithelial-mesenchymal transition contributes to nephrolithiasis-induced renal fibrosis.

PURPOSE: To investigate fibrotic lesions in renal tissues obtained from patients with large calculi, and to selectively evaluate the expression and clinical significance of Twist and E-cadherin in nephrolithiasis patients. METHODS: We recruited 50 patients with kidney stone and 32 matched healthy controls. We determined plasma creatinine (Cr) and corrected Cr clearance (CCr). For the 50 patients, we detected daily urine protein excretion. At the end of percutaneous nephroscopic lithotomy, we performed puncture biopsy to acquire kidney tissue. We obtained normal control kidney tissues from non-nephrolithiasis patients who received a surgical biopsy during open surgery. We determined the expression of Twist and E-cadherin by immunohistochemical staining and scored it with clinical parameters. In addition, we analyzed the degree of expression of Twist and its correlation with long-term renal survival. RESULTS: Overall, the renal function of patients significantly decreased, as indicated by Cr and reduced CCr compared with healthy controls. Activated Twist was strongly expressed in tubular epithelial cells from kidneys of nephrolithiasis patients, whereas we found little positive staining of Twist in normal kidneys. Meanwhile, the expression of E-cadherin was significantly suppressed in kidneys of nephrolithiasis patients. Twist expression was inversely correlated with E-cadherin expression; using multivariate analysis, data showed that the factors influencing renal survival in patients were CCr (relative ratio, 4.39; 95% confidence interval, 1.34-14.38; P = 0.013) and the extent of Twist expression (relative ratio, 3.45; 95% confidence interval, 1.10-10.68; P = 0.033). CONCLUSIONS: Our data suggest that the possible novel EMT marker molecule Twist and Twist staining might be a valuable index predicting renal fibrosis progression in human nephrolithiasis.

Epigallocatechin gallate attenuates interstitial cystitis in human bladder urothelium cells by modulating purinergic receptors.

BACKGROUND: Epigallocatechin gallate (EGCG) has exhibited antitumor properties against bladder cancer. However, its effects in interstitial cystitis (IC) have not been investigated. METHODS: Here, we performed repeated cystoscopy and re-biopsy of bladder mucosa before and after intravesical irrigation of EGCG in eight patients diagnosed with IC based on clinical and histopathologic assessments. Six normal bladder tissue samples were obtained from age-, race-, and sex-matched asymptomatic control subjects. IC symptom index was used to compare the therapeutic effect in IC patients. Patient-derived bladder epithelial cells were cultured and cell stretch experiments and ATP assays were performed. The expression of purinergic receptors X1, X2, and X3, and Y1, Y2, and Y11, in biopsied samples was detected by Western blotting and real-time polymerase chain reaction, respectively. Moreover, the expression of inducible NO synthase, phosphorylated Akt, and phosphorylated NF-κB was also assessed. RESULTS: All EGCG-treated patients demonstrated different extents of remission of symptoms. We found a significant upregulation in P2X1, P2X2, and P2X3 receptor proteins and P2Y1, P2Y2, and P2Y11 receptor transcripts in IC patients. However, EGCG therapy attenuated the expression of all purinergic receptors. In addition, EGCG demonstrated prominent antioxidative and antiinflammatory effects via inhibition of the upregulation of iNOS and phosphorylated NF-κB. Furthermore, the stretch-activated release of ATP in cultured bladder urothelial cells was greater in cells derived from IC patients, compared with those from the control patients, but EGCG, at all concentrations tested, effectively abolished the increase in ATP release from stretched IC patient-derived cells. CONCLUSIONS: Our study suggests that inhibition of the expression of purinergic receptors and ATP release in urothelial cells by EGCG supports further development of EGCG as a novel therapeutic option for IC.

Protective effects of SP600125 on renal ischemia-reperfusion injury in rats.

BACKGROUND: Ischemia/reperfusion injury (IRI) has a negative effect on renal allograft survival. Using a rat model of kidney IRI in this study, we investigated the overall effect of selective c-Jun N-terminal kinase (JNK) inhibitor SP600125 on renal IRI events. METHODS: All 45 Fisher rats were anesthetized and renal IRI model was established by 45 min clamp of bilateral renal pedicles and 24 h reperfusion. Vehicle solution or SP600125 solution was intraperitoneally injected 45 min before ischemia, respectively. Analysis of renal histology, function, reactive oxygen species (ROS) expression, JNK phosphorylation status, as well as intra-renal pro-inflammatory cytokines expression was evaluated in this study. RESULTS: After IRI, the levels of blood urea nitrogen, creatinine, tissue malondialdehyde, TNF-α, IL-1ß, IL-6 were all elevated significantly, while superoxide dismutase, catalase activity were decreased. Histologic findings showed severe devastating lesions and increased rodent cell apoptosis; SP600125 effectively improved morphologic features, reversed above-mentioned parameters, and significantly attenuated c-Jun phosphorylation, as well as intra-renal pro-inflammatory cytokines expression compared with vehicle-treated group. CONCLUSION: These data demonstrate that inhibition of c-Jun with SP600125 is capable of attenuating renal IRI, which might be a novel therapy target.

[Laparoendoscopic single-site retroperitoneal adrenalectomy:a report of 7 cases].

OBJECTIVE: To summarize our preliminary clinical experiences of laparoendoscopic single-site (LESS) retroperitoneal adrenalectomy. METHODS: Since October 2009 to January 2011, the investigators have performed LESS retroperitoneal adrenalectomy for 7 patients with adrenal tumors. A waist axillary midline incision of around 2 - 3 cm was made and a single incision for inserting a homemade port. Cambridge endo flexible laparoscopic instrument and other common laparoscopic accessories were used during the surgical procedures. RESULTS: LESS retroperitoneal adrenalectomies were technically successful in 6 cases with no extra skin incisions, no conversion into an open procedure or standard laparoscopy. Conversion to standard laparoscopy (3 ports) was inevitable in one case. The reason for conversion was due to tumor size (6 cm). No perioperative complication occurred. The mean operative duration was 139 min (95 - 200 min), the mean volume of blood loss 96 ml (30 - 350 ml) and the mean hospital stay 5 d (3 - 8 d). CONCLUSION: LESS retroperitoneal adrenalectomy is technically feasible and safe for the treatment of small adrenal tumors.

[Transurethral ureteroscopy in the diagnosis and treatment of hemospermia].

OBJECTIVE: To explore the clinical application value of transurethral ureteroscopy in the diagnosis and treatment of hemospermia. METHODS: We summed up and analyzed the experience in the diagnosis and treatment of 43 hemospermia patients by transurethral ureteroscopy and douching therapy. RESULTS: The disease causes were clearly determined and the therapeutic procedures successfully accomplished in all the cases. The mean surgical time was 20 (18 -45) minutes. No significant complications developed either intraoperatively or postoperatively. The patients were followed up for 1 -24 months, during which hemospermia symptoms completely disappeared in 35 and were relieved in 6 of the cases, but the other 2 remained unimproved. All the patients had normal sexual life and none experienced retroinfection postoperatively. CONCLUSION: Transurethral ureteroscopy, advantageous for its safety, high rate of detection, good effect of treatment and fewer complications, deserves to be popularized in the clinical diagnosis and treatment of hemospermia.

circPRRC2A promotes angiogenesis and metastasis through epithelial-mesenchymal transition and upregulates TRPM3 in renal cell carcinoma.

Background: Circular RNAs (circRNAs) have been identified as essential regulators in a plethora of cancers. Nonetheless, the mechanistic functions of circRNAs in Renal Cell Carcinoma (RCC) remain largely unknown. Methods: In this study, we aimed to identify novel circRNAs that regulate RCC epithelial-mesenchymal transition (EMT), and to subsequently determine their regulatory mechanisms and clinical significance. Results: circPRRC2A was identified by circRNA microarray and validated by qRT-PCR. The role of circPRRC2A in RCC metastasis was evaluated both in vitro and in vivo. We found that increased expression of circPRRC2A is positively associated with advanced clinical stage and worse survivorship in RCC patients. Mechanistically, our results indicate that circPRRC2A prevents the degradation of TRPM3, a tissue-specific oncogene, mRNA by sponging miR-514a-5p and miR-6776-5p. Moreover, circPRRC2A promotes tumor EMT and aggressiveness in patients with RCC. Conclusions: These findings infer the exciting possibility that circPRRC2A may be exploited as a therapeutic and prognostic target for RCC patients.

Retrospective analysis of fosfomycin combinational therapy for sepsis caused by carbapenem-resistant Klebsiella pneumoniae.

The aim of the present study was to compare the efficacy and safety of fosfomycin combinational therapy with other antibiotics for the treatment of infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). This retrospective cohort study examined 104 cases of sepsis caused by CRKP occurring between January 2012 and November 2014 in Shanghai Tenth People's Hospital. Three categories of patient outcome were assessed: Survival/mortality, duration of intensive care unit stays and duration of medical ventilation. Univariate ordinal analyses were adopted to evaluate the correlations between outcome and treatment. A total of 104 patients with physician-diagnosed CRKP were involved in the study. The overall mortality rate was 25.0%. The majority of the infections (84; 80.8%) were hospital acquired. Critical infections received more than one active antibiotic as therapy. Patients treated with fosfomycin combinational therapy were less likely to fail therapy (OR: 4.71, 95% CI: 1.03-21.65, P=0.034) and tended to have a shorter duration of mechanical ventilation. Gender (OR: 4.35, 95% CI: 1.08-3.60, P=0.037), history of chronic obstructive pulmonary disease (OR: 9.35, 95% CI: 0.06-0.19, P=0.007) and peripheral catheter use (OR: 3.00, 95% CI: 0.07-0.19, P=0.002) are risk factors for clinical outcome. Therefore, the use of fosfomycin combinational therapy for treatment of infection due to CRKP appears to be associated with improved survival rate.

Combination of quercetin and hyperoside inhibits prostate cancer cell growth and metastasis via regulation of microRNA­21.

Previous studies have reported that hyperoside and quercetin in combination (QH; 1:1) inhibited the growth of human leukemia cells. The aim of the present study was to investigate the anti­cancer effect of QH on prostate cancer cells. The results demonstrated that QH decreased the production of reactive oxygen species (ROS) and increased antioxidant capacity in PC3 cells at various concentrations (2.5­60 µg/ml) with peak inhibition and augmentation changes of 3.22­ and 3.00­fold, respectively. Following treatment with QH for 48 and 72 h, the IC50-values on PC3 cells were 19.7 and 12.4 µg/ml, respectively. Western blot analysis revealed that QH induced apoptosis in human prostate cancer cells via activation of caspase­3 and cleavage of poly(adenosine diphosphate ribose) polymerase. In addition, QH significantly inhibited the invasion and migration of PC3 cells as well as reduced the expression of numerous prostate tumor­associated microRNAs (miRs), including miR­21, compared to that of untreated human prostate cancer cells. QH was also found to enhance the expression of tumor suppressor programmed cell death protein 4, which was negatively regulated by miR­21. Furthermore, induced overexpression of miR­21 using pre­miR­21 oligonucleotides attenuated the beneficial effect of QH on prostate cancer cells. In conclusion, the results of the present study indicated that QH exerted an anti­cancer effect on human prostate cancer cells, the mechanism of which proceeded, at least in part, via the inhibition of the miR­21 signaling pathway.

Decreased expression of long non-coding RNA NBAT-1 is associated with poor prognosis in patients with clear cell renal cell carcinoma.

OBJECTIVE: accumulating evidence suggest that long non-coding RNAs (lncRNAs) may play important roles in human cancers. LncRNA neuroblastoma associated transcript-1 (NBAT-1) was initially identified to be involved in the progression of neuroblastoma. However, there is no report about the role of NBAT-1 in clear cell renal cell carcinoma (ccRCC). The purpose of this study is to investigate the clinical significant of NBAT-1 in ccRCC. METHODS: the expression pattern of NBAT-1 in ccRCC patients and renal cancer cell lines was detected by using quantitative real-time PCR (qRT-PCR), and its correlation with clinicopathologic features and prognosis of patients with ccRCC was assessed by Kaplan-Meier method and Cox proportional hazards model, respectively. Small interfering RNA (siRNA) was transfected into 786-O and ACHN cells to determine the effect of NBAT-1 knockdown on renal cancer cells. RESULT: NBAT-1 expression is significantly decreased in ccRCC tissues and renal cancer cells compared with adjacent normal tissues and normal human proximal tubule epithelial cell line HK-2, and its low level is associated with advanced features and poor prognosis. Also, multivariate analysis identified NBAT-1 expression as an independent prognostic factor for ccRCC. In vitro assays indicated that knockdown of NBAT-1 expression increased renal cancer cell proliferation, migration and invasion. CONCLUSIONS: NBAT-1 is a novel molecular correlated with ccRCC progression; and it may represent a prognostic biomarker and therapeutic target in renal cancer diagnosis and treatment.

Nrf2 sensitizes prostate cancer cells to radiation via decreasing basal ROS levels.

Androgen deprivation therapy (ADT) was reported to lower basal ROS level in prostate cancer (PCa) and to sensitize PCa to radiation. We aimed to seek for the underlying molecular mechanism and to develop novel additive treatments to ADT in this regard. We simulated human androgen milieu in vitro and tested the ROS level in PCa cells undergoing ADT. We also tested the Nrf2 level in PCa cells with or without ADT. Genetic and pharmaceutical upregulation of Nrf2 was applied in vitro and in vivo in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice with or without castration to investigate whether Nrf2 overexpression supplemented the effect of ADT in PCa. We first discovered that androgen deprivation increased basal ROS level in PCa cells with AR expression. We then found that genetic Nrf2 upregulation lowered basal ROS similar to ADT. Also, SFN sensitized PCa cell to radiation via upregulation of Nrf2. We then found that Nrf2 level in control TRAMP groups was lower than castration or SFN groups. The SFN treated TRAMP mice showed similar level of Nrf2 to castration. Genetic and pharmaceutical upregulation of Nrf2 lowered the ROS in PCa cells and sensitized PCa cells to radiation similar to ADT, implicating possible administration of SFN in place of ADT for PCa patients requiring radiotherapy.

High expression of long non-coding RNA SPRY4-IT1 predicts poor prognosis of clear cell renal cell carcinoma.

INTRODUCTION: Long non-coding RNAs (lncRNAs) play a key role in cellular processes, such as cell growth, apoptosis, and carcinogenesis. lncRNAs SPRY4-IT1 has recently been identified to be involved in tumorigenesis of several cancers such as non-small cell lung cancer and esophageal squamous cell carcinoma. However, the role of SPRY4-IT1 in clear cell renal cell carcinoma (ccRCC) remains unclear. METHODS: The expression of SPRY4-IT1 was examined in ccRCC patients and renal cancer cell lines by using quantitative real-time PCR (qRT-PCR). The relationship between SPRY4-IT1 level and clinicopathological parameters of ccRCC was analyzed with the Kaplan-Meier method and Cox proportional hazards model. Small interfering RNA (siRNA) was used to suppress SPRY4-IT1 expression in renal cancer cell line 786-O. In vitro assays were performed to further explore its role in renal cancer progressio. RESULTS: The relative level of SPRY4-IT1 was significantly higher in ccRCC tissues compared to the adjacent normal renal tissues. And higher expression of SPRY4-IT1 was found in renal cancer cell lines compared with the normal human proximal tubule epithelial cell line HK-2. The ccRCC patients with higher SPRY4-IT1 expression had an advanced clinical stage and poorer prognosis than those with lower SPRY4-IT1 expression. Multivariate analyses by Cox's proportional hazard model revealed that expression of SPRY4-IT1 was an independent prognostic factor in ccRCC. In vitro assays, our results indicated that knockdown of SPRY4-IT1 reduced renal cancer cell proliferation, migration, and invasion. CONCLUSIONS: Our data suggested that lncRNA SPRY4-IT1 might be considered as a potential prognostic indicator and a potential target for therapeutic intervention in RC.

Metformin inhibits cell growth by upregulating microRNA-26a in renal cancer cells.

Accumulating evidence suggests that metformin, a biguanide class of anti-diabetic drugs, possesses anti-cancer properties and may reduce cancer risk and improve prognosis. However, the mechanism by which metformin affects various cancers, including renal cancer still unknown. MiR-26a induces cell growth, cell cycle and cell apoptosis progression via direct targeting of Bcl-2, clyclin D1 and PTEN in cancer cells. In the present study, we used 786-O human renal cancer cell lines to study the effects and mechanisms of metformin. Metformin treatment inhibited RCC cells proliferation by increasing expression of miR-26a in 786-O cells (P < 0.05). As a result, protein abundance of Bcl-2 and cyclin D1 was decreased and PTEN was increased in cells exposed to metformin. Also over-expression of miR-26a can inhibited cell proliferation by down-regulating Bcl-2, cyclin D1 and up-regulating PTEN expression. Therefore, these data for the first time provide novel evidence for a mechanism that the anticancer activities of metformin are due to upregulation of miR-26a and affect its downstream target gene.

Combination of quercetin and hyperoside has anticancer effects on renal cancer cells through inhibition of oncogenic microRNA-27a.

Quercetin and hyperoside (QH) in combination (1:1 ratio) have previously been shown to inhibit the growth of human leukemia cells. Here, we investigated the anticancer activity of the same mixture in 786-O renal cancer cells. QH decreased the generation of reactive oxygen species (ROS) by up to 2.25-fold and increased the antioxidant capacity by up to 3-fold in 786-O cells (3.8-60 µg/ml), whereas IC50 values for viability were 18.2, 18.7 and 11.8 µg/ml, respectively. QH also induced caspase-3 cleavage (2-fold) and increased PARP cleavage. Specificity protein (Sp) transcription factors are overexpressed in cancer cells and regulate genes required for cell proliferation, survival and angiogenesis. QH treatment decreased the expression of Sp1, Sp3 and Sp4 mRNA and this was accompanied by decreased protein expression. Moreover, expression of the Sp-dependent anti-apoptotic survival gene survivin was also significantly reduced, both at the mRNA and protein levels. QH decreased microRNA-27a (miR-27a) and induced the zinc finger protein ZBTB10, an Sp-repressor, suggesting that interactions between QH and the miR-27a-ZBTB10 axis play a role in Sp downregulation. This was confirmed by transfection of cells with a specific mimic for miR-27a, which partially reversed the effects of QH. These findings are consistent with previous studies on botanical anticancer agents in colon cancer cells.

Prophylactic effects of quercetin and hyperoside in a calcium oxalate stone forming rat model.

Quercetin and hyperoside (QH) are the two main constituents of the total flavone glycosides of Flos Abelmoschus manihot, which has been prescribed for treating chronic kidney disease for decades. This study aimed to investigate the effect of QH on calcium oxalate (CaOx) formation in ethylene glycol (EG)-fed rats. Rats were divided into three groups: an untreated stone-forming group, a QH-treated stone-forming group (20 mg/kg/day) and a potassium citrate-treated stone-forming group (potassium citrate was a worldwide-recognized calculi-prophylactic medicine). Ethylene glycol (0.5 %) was administered to the rats during the last week, and vitamin D3 was force-fed to induce hyperoxaluria and kidney calcium oxalate crystal deposition. 24 h urine samples were collected before and after inducing crystal deposits. Rats were killed and both kidneys were harvested after 3 weeks. Bisected kidneys were examined under a polarized light microscope for semi-quantification of the crystal-formation. The renal tissue superoxide dismutase and catalase levels were measured by Western blot. QH and potassium citrate have the ability to alkalinize urine. The number of crystal deposits decreased significantly in the QH-treated stone-forming group as compared to the other groups. Superoxide dismutase and catalase levels also increased significantly in the QH-treated stone-forming group, as compared with the untreated stone-forming group. QH administration has an inhibitory effect on the deposition of CaOx crystal in EG-fed rats and may be effective for preventing stone-forming disease.

Fibrinogen alpha chain precursor and apolipoprotein A-I in urine as biomarkers for noninvasive diagnosis of calcium oxalate nephrolithiasis: a proteomics study.

UNLABELLED: Calcium oxalate nephrolithiasis is the most common urological disease, but noninvasive and convenient methods of diagnosis are rarely available. OBJECTIVE: The present study aimed to identify potential urine biomarkers for noninvasive diagnosis of CaOx nephrolithiasis. METHODOLOGY: Urine samples from 72 patients with CaOx nephrolithiasis and 30 healthy controls were collected and proteomics analysis was performed using matrix-assisted laser desorption/ionization-time of flight-mass spectrometer (MALDI-TOF-MS). RESULTS: Thirteen proteins/peptides displayed statistically significant differences. The peptides of m/z 1207.23 and 2773.86 were selected by the genetic algorithm (GA) to build a possible diagnostic model. The area under the curve of m/z 1207.23 and 2773.86 was 0.936 and 0.987, respectively. The diagnostic model in distinguishing patients and healthy subjects showed 100% sensitivity and specificity. The peak at m/z 2773.86 was identified as fibrinogen alpha chain (FGA) with the sequence G.EGDFLAEGGGVR.G, and the peak at m/z 2773.86 was identified as apolipoprotein A-I (apoA-I) with the sequence L.PVLESFKVSFLSALEEYTKKLNTQ. CONCLUSION: The study results strongly suggested that urinary FGA and apoA-I are highly sensitive and specific biomarkers for noninvasive diagnosis of CaOx nephrolithiasis.