SGK2 promotes renal cancer progression via enhancing ERK 1/2 and AKT phosphorylation.

OBJECTIVE: Increasing studies reported that the serum- and glucocorticoid-inducible kinases (SGKs) contributed to the tumorigenesis of various cancer. In this article, we are aiming to explore the function of SGK2 in renal cell cancer (RCC). PATIENTS AND METHODS: In this study, the SGK2 expression was quantified by Western blot (WB) in multiple RCC cell lines. And in vitro SGK2 knockdown and overexpression experiments were also performed. In addition, molecular function analysis was performed using FunRich software V3. The Cancer Genome Atlas (TCGA) database was retrieved to verify the association between the SGK2 expression and the prognosis of RCC patients. RESULTS: We found that SGK2 was up-regulated in RCC tissues compared with adjacent normal tissues, and the SGK2 expression also increased in various RCC cell lines compared to that in the normal epithelial cell line HK-2. Meanwhile, the SGK2 expression was significantly associated with the survival rate of RCC patients. Functional experiments showed that silencing SGK2 expression inhibited RCC cells proliferation, migration, colony formation and invasion abilities in vitro, whereas opposite results were uncovered after overexpressing SGK2 in RCC cells. Furthermore, functional analyses showed that SGK2 related genes were associated with protein serine/threonine kinase activity, guanosine triphosphatase (GTPase) activity, guanyl-nucleotide exchange factor activity, and motor activity. Protein interaction analysis identified that growth factor receptor-bound protein 2 (GRB2), one of the most important upstream components in the growth factor signaling pathway, was significantly enriched in SGK2 related genes. In addition, the WB assay validated that SGK2 could promote the phosphorylation of ERK 1/2 and AKT. CONCLUSIONS: Our results suggested that SGK2 promoted RCC progression by mediating the phosphorylation of extracellular regulated protein kinases (ERK) 1/2 and Protein kinase B (AKT/PKB), indicating that SGK2 might serve as a potential prognostic marker and therapeutic target for renal cancer patients.

[Retroperitoneal laparoscopic with renal pedicle rotation for partial nephrectomy of ventro-renal tumor].

OBJECTIVE: Retro-laparoscopic partial nephrectomy is a challenge for ventro-renal tumors, especially hilar tumors. The tumors are partial or entirely out of operative field and there is blind space for operation. To solve this problem, a set of techniques including renal pedicle rotation is developed. METHODS: A set of techniques including renal pedicle rotation, double-layer suture, early artery unclamping for retro-laparoscopic nephrectomy for ventro-renal tumors, especially hilar tumors were developed. Hilar tumors were located anteriorly to the angle of the renal and renal arteries and in contact with the anterior surface of the renal artery. The evaluation of the outcomes included the operation time, warm ischemia time, estimated haemorrhage, surgical margin, renal function after operation, and complications. This study reviewed the data of 28 patients with ventro-renal tumor, including 15 patients with complex hilar tumors. RESULTS: The average tumor size was (3.8±0.5) cm. The average R.E.N.A.L score was 8 (ranging from 7 to 9). The average warm ischemia time was (23.8±4.7) min, and suture time was (26.2±6.5) min, and operation time was (124.1±12.1) min. The median hospital stay was 4 days and the average estimated haemorrhage was (139.1±54.0) mL. All the surgeries were operated under laparoscope and no surgery switched to open surgery. Seven patients developed Clavien Dindo I-II complications after operation. Three patients (10.7%) developed collective system damage and received repair of collective system in time and three patients (10.7%) developed slightly gross hematuria (Clavien-Dindo I). Two patients developed wound infection (Clavien-Dind II). Three patients (10.7%) got renal vein clamped because of capillary hemorrhage from basilar part of tumors. There were 14 patients received early unclamping of renal artery, and no obvious renal vessel damage was found. There were statistically significant differences between the serum creatinine levels (P<0.05) and the estimated glomerular filtration rates (P=0.02) before and after surgery. All the patients' serum creatinine levels were in normal range and no patient needed regular dialysis. There was no positive surgical margin and the median follow-up was 7 months without local recurrence or distant metastasis. CONCLUSION: It is safe and effective to apply renal pedicle rotation technique in retro-laparoscopic partial nephrectomy for ventro-renal tumors. The short-term follow-up results are optimistic, but long follow-up is required.

Shorter hemodialysis duration is a risk factor for the recurrence of urothelial carcinoma of the bladder in patients on maintenance hemodialysis.

PURPOSE: To investigate the association of hemodialysis duration with the recurrence of urothelial carcinoma (UC) of the bladder and overall survival in patients undergoing maintenance hemodialysis (MHD). PATIENTS AND METHODS: 52 bladder cancer patients who underwent MHD at the Xiangya Hospital of The Central South University between 2001 and 2011 were enrolled in the study. The patients were divided into three groups according to hemodialysis duration, and patient mortality and tumor recurrence rates were analyzed. The association of hemodialysis duration with occurrence and recurrence of UC of the bladder was analyzed by Cox regression analysis. Survival was evaluated by the Kaplan-Meier method. RESULTS: Out of 6266 chronic hemodialysis patients, 52 patients had UC of the bladder after the initiation of hemodialysis for 6 months. The mean age at hemodialysis onset was 55 years (IQR 36, 71). The major complaints were painless gross hematuria and urethral bloody discharge. Tumors were generally large and multifocal. The standardized incidence ratio of UC of the bladder was 43.9 compared with general population, and it was higher in women (76.7) and in the age group 61-65 years (186.6). The mean hemodialysis duration before the diagnosis of bladder cancer was 32 months. 30 (57.7 %) patients received hemodialysis no more than 3 years, 10 (19.2 %) patients received hemodialysis between 3 and 6 years, and 12 (23.1 %) patients received hemodialysis for more than 6 years. CONCLUSION: Preoperative shorter hemodialysis duration is a risk factor for the occurrence and recurrence of UC of the bladder in patients undergoing MHD.