The Current and Future Application of Adjuvant Systemic Chemotherapy in Patients with Bladder Cancer Following Cystectomy

ERVK13-1/miR-873-5p/GNMT Axis Promotes Metastatic Potential in Human Bladder Cancer though Sarcosine Production

N-methyl-glycine (sarcosine) is known to promote metastatic potential in some cancers; however, its effects on bladder cancer are unclear. T24 cells derived from invasive cancer highly expressed GNMT, and S-adenosyl methionine (SAM) treatment increased sarcosine production, promoting proliferation, invasion, anti-apoptotic survival, sphere formation, and drug resistance. In contrast, RT4 cells derived from non-invasive cancers expressed low GNMT, and SAM treatment did not produce sarcosine and did not promote malignant phenotypes. In T24 cells, the expression of miR-873-5p, which suppresses GNMT expression, was suppressed, and the expression of ERVK13-1, which sponges miR-873-5p, was increased. The growth of subcutaneous tumors, lung metastasis, and intratumoral GNMT expression in SAM-treated nude mice was suppressed in T24 cells with ERVK13-1 knockdown but promoted in RT4 cells treated with miR-873-5p inhibitor. An increase in mouse urinary sarcosine levels was observed to correlate with tumor weight. Immunostaining of 86 human bladder cancer cases showed that GNMT expression was higher in cases with muscle invasion and metastasis. Additionally, urinary sarcosine concentrations increased in cases of muscle invasion. Notably, urinary sarcosine concentration may serve as a marker for muscle invasion in bladder cancer; however, further investigation is necessitated.

[Oncological results of a series of 93 laparoscopic radical cystectomies: 5 years of follow-up]

OBJECTIVE

To report oncological results at 5 years after laparoscopic radical cystectomy (LRC) with lymph node dissection for bladder cancer (BC).

PATIENTS AND METHODS

This is a retrospective single-center study of all patients who underwent LRC for BC by the same surgeon from February 2007 to March 2016. Demographic, perioperative and oncologic data were collected. We reported overall survival rate (OS), cancer specific (CSS) and recurrence-free survival (SSR), as primary indicators of oncologycal outcomes. These survival rates were estimated according to the Kaplan-Meier method. Log-rank tests were used to explore overall survival according tumor stage, lymph node involvement and surgical margins status.

RESULTS

In all, 93 patients (82 men and 11 women) underwent LRC. Mean age was 59 years. Minor complications (Clavien I-II) occurred in 24.7%. Major complications (Clavien IIIa-V) were observed in 8.6%. No patients received neoadjuvant chemotherapy. Median lymph node (LN) yield was 15 and 26.5% patients had positive LN. The positive surgical margins (SMs) rate was 5.3%. Median follow-up for the entire patients was 50 months (19-84 months). Forty-three patients (46.2%) were followed for at least 71 months. Five year RFS, CSS and OS were 67%, 85% and 79%, respectively. Non organ confined desease, positive LN and positive SMs were associated with poorer OS (P<0.039, P<0.016 and P<0.001).

CONCLUSION

LRC was associated with acceptable long-term oncologic outcomes, similar to those currently reported after open cystectomy for BC.

LEVEL OF EVIDENCE

3.

Pro-chemotherapeutic effects of antibody against extracellular domain of claudin-4 in bladder cancer

Bladder cancer displays an aggressive phenotype in the muscle-invasive phase, and is associated with a high mortality rate. Therefore, novel molecular therapeutic targets are needed to improve patient survival. A monoclonal antibody against the extracellular domain of the claudin-4 (CLDN4) tight junction protein was established by immunizing rats with a plasmid vector encoding human CLDN4. A hybridoma clone, producing a rat monoclonal antibody recognizing CLDN4 (clone 4D3), was obtained. Immunohistochemistry by using the 4D3 antibody showed that CLDN4 expression was associated with local invasion, nodal metastasis, distant metastasis, and advanced stage in 86 cases of bladder cancer. The 4D3 antibody inhibited growth, invasion, and survival, associated with abrogation of the intratumoral microenvironment; lowered concentrations of epidermal growth factor and vascular endothelial growth factor were found in three-dimensional cultures of T24 and RT4 cells. In combination with cisplatin therapy, 4D3 enhanced cisplatin cytotoxicity by increasing cellular permeability, leading to increased intracellular cisplatin concentrations. In mouse models of subcutaneous tumors and lung metastasis, 4D3 enhanced tumor growth inhibition, alone and with concurrent cisplatin treatment. The anti-tumor activity of the newly established 4D3 antibody suggests that it may be a powerful tool in CLDN4-targeting therapy, and in combination with chemotherapy.

Cell damage and death by autoschizis in human bladder (RT4) carcinoma cells resulting from treatment with ascorbate and menadione

A human bladder carcinoma cell line RT4 was sham-treated with buffer or treated with ascorbate (VC) alone, menadione alone (VK(3)), or a combination of ascorbate:menadione (VC+VK(3)) for 1, 2, and 4 h. Cytotoxic damage was found to be treatment-dependent in this sequence: VC+VK(3)>VC>VK(3)>sham. The combined treatment induced the greatest oxidative stress, with early tumor cell injury affecting the cytoskeletal architecture and contributing to the self-excisions of pieces of cytoplasm freed from organelles. Additional damage, including a reduction in cell size, organelle alterations, nuclear damage, and nucleic acid degradation as well as compromised lysosome integrity, is caused by reactivation of DNases and the redox cycling of VC or VC+VK(3). In addition, cell death caused by VC+VK(3) treatment as well as by prolonged VC treatment is consistent with cell demise by autoschizis, not apoptosis. This report confirms and complements previous observations about this new mode of tumor cell death. It supports the contention that a combination of VC+VK(3), also named Apatone, could be co-administered as a nontoxic adjuvant with radiation and/or chemotherapies to kill bladder tumor cells and other cancer cells without any supplementary risk or side effects for patients.

Combining surgery and chemotherapy for invasive bladder cancer: current and future directions

More than 13,000 patients died from invasive bladder cancer in 2005 alone. Radical cystectomy is the most commonly prescribed treatment for patients with muscle-invasive bladder cancer, or for those with a nonmuscle-invasive disease that is refractory to intravesical therapy. Despite advances in surgical technique and improved understanding of the role of pelvic lymphadenectomy, 5-year survival probabilities suggest that improvements in treatment are necessary. The maturation of several randomized clinical trials on perioperative chemotherapy, and particularly neoadjuvant chemotherapy, clearly suggest that an integrated treatment program of systemic chemotherapy and definitive locoregional therapy may improve the outcome for bladder cancer patients. The next frontier is the molecular characterization of this spectrum of diseases that make up invasive bladder cancer and targeted therapeutics. Prospective validation of molecular markers and evaluation of novel therapeutic agents, alone or in combination with established cytotoxic agents, provide hope of better outcomes for bladder cancer patients.