Laparoscopic pelvic lymph node dissection system based on preoperative primary tumour stage (T stage) by computed tomography in urothelial bladder cancer: results of a single-institution prospective study.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Bladder cancer (BC) is a public health problem throughout the world, and now radical cystectomy (RC) has been introduced as a standard treatment for BC invading muscle and some BCs not invading muscle. Pelvic lymph node dissection (PLND) is considered an integral part of RC for its prognostic and therapeutic significance, but the extent of the PLND has not been precisely defined. Computed tomography is considered one of the most preferable methods to assess the BC stage preoperatively because of its high sensitivity and specificity. However, there are few articles referring to CT as an aid in deciding the extent of lymphadenectomy during RC. In the present study, we prospectively studied the clinical value of preoperative CT staging of primary tumours in deciding the extent of PLND during laparoscopic RC in the management of BC. The preliminary findings suggested that all patients with higher preoperative CT stage should be given super-extended PLND during RC. For those with lower CT stage, careful and thorough clearance of all lymphatic and adipose tissues within the true pelvis could be more helpful than super-extended PLND. OBJECTIVE: To study prospectively the clinical value of preoperative spiral computed tomography (CT) staging of primary tumours in deciding the extent of pelvic lymph node dissection (PLND) during laparoscopic radical cystectomy (RC) in the management of bladder cancer (BC). PATIENTS AND METHODS: Between January 2010 and December 2011, a total of 63 patients with urothelial BC received laparoscopic RC, super-extended PLND and ileac conduit. The super-extended PLND removed all lymphatic tissues in the boundaries at the level of the inferior mesenteric origin from the aorta (cephalad), the pelvic floor (distally), the genitofemoral nerve (laterally) and the sacral promontory (posteriorly). All of the operations were performed by one experienced surgeon, and all harvested lymph nodes were submitted separately. CT was used to evaluate the preoperative CT stage (CTx) of each primary bladder tumour. RESULTS: All patients were divided into five categories according to their CTx stages: three at CT1, seven at CT2a, 38 at CT2b, seven at CT3b, and eight at CT4a. All 63 procedures were completed successfully without any conversion to open surgery. The mean estimated blood loss was 450 mL, and 14 patients (22.2%) had postoperative lymphatic leakage. Each case was pathologically confirmed as transitional cell carcinoma with negative margins at the urethral and ureteric stumps. None of the patients with a low CTx stage (CT1-CT2a) had positive lymph nodes above the level of the common iliac artery bifurcation. There was no jump lymph node metastasis, and no positive lymph node was detected above the level of aortic bifurcation in all cases. CONCLUSION: Based on the preoperative CT staging, urological surgeons can determine the boundaries of PLND to reduce intraoperative injury and postoperative complications in patients with BC, especially those at the lower CTx stages (CT1 and CT2a).

A proteomic study of potential VEGF-C-associated proteins in bladder cancer T24 cells.

BACKGROUND: Overexpression of vascular endothelial growth factor-C (VEGF-C) has been found to play an important role in malignant progression of various cancer cells, in addition to lymphangiogenesis. However, the mechanisms involved are still largely unknown. Our early research has confirmed that the expression of VEGF-C in bladder cancer was markedly higher than that in normal bladder tissues. VEGF-C can also obviously promote proliferation and invasion of bladder cancer T24 cells. In the present work, we attempted to use proteomic analysis to screen out potential VEGF-C-associated proteins involved in malignant progression of the bladder cancer T24 cells. MATERIAL/METHODS: Lentivirus vector-based RNA interference (RNAi) was employed to diminish VEGF-C expression of bladder cancer T24 cells. Then we performed comparative proteome analysis to explore differentially expressed proteins in T24 cells with and without VEGF-C siRNA, by two-dimensional difference gel electrophoresis (2D-DIGE). RESULTS: Twenty-three proteins were identified. Some proteins (matrix metalloproteinase-9, Keratin 8, Serpin B5, Annexin A8) with significant differences were further confirmed by Western blotting. CONCLUSIONS: The 23 potential VEGF-C-associated proteins identified in our study provide us with further insights into the mechanism of VEGF-C promoting malignant progression of bladder cancer cells.

RNA interference-mediated vascular endothelial growth factor-C reduction suppresses malignant progression and enhances mitomycin C sensitivity of bladder cancer T24 cells.

Vascular endothelial growth factor-C (VEGF-C) has been found to be significantly associated with lymphangiogenesis and regional lymph node metastasis in various human tumors. The present work was aimed to explore the role of VEGF-C in malignant progression of human bladder cancer T24 cell line. First, the expression of VEGF-C in T24 cells was detected by western blotting. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was employed to measure the cellular proliferation after treatment with various concentrations of recombinant human VEGF-C (rhVEGF-C). Then, lentivirus vector-based RNA interference (RNAi) was used to inhibit VEGF-C expression of T24 cells. The alterations of T24 cells regarding proliferation, invasiveness, and the apoptosis induced by mitomycin C (MMC) were evaluated. The results showed that the proliferation rate of T24 cells rose from 27.3% to 65.0%, with increasing rhVEGF-C concentration. T24 cells stably transfected with VEGF-C small interference RNA showed 85% reduction in VEGF-C mRNA expression (p < 0.05). The VEGF-C protein level was significantly downregulated (p < 0.05) and the growth and invasiveness were also inhibited (p < 0.05) compared with the control group. Further, the inhibition of VEGF-C expression markedly enhanced the apoptosis of T24 cells induced by MMC (p < 0.05). These were associated with the decreased ratio of Bcl-2/Bax, activation of Caspase-3, decreased expression of MMP-9, as well as the downregulation of phosphorylated p38 MAPK and Akt. The present study suggests that VEGF-C can enhance the proliferation and invasiveness of bladder cancer T24 cells, which is due to suppression of apoptosis and facilitation of migration, accompanied with upregulation of p38 MAPK and Akt phosphorylation. RNAi targeting VEGF-C could effectively suppress malignant progression and enhance chemosensitivity of T24 cells. Thus, inhibition of VEGF-C expression is a potential and promising therapeutic strategy for bladder cancer.