Advanced bladder cancer: new agents and new approaches. A review

Pharmacological NF-κB inhibition decreases cisplatin chemoresistance in muscle-invasive bladder cancer and reduces cisplatin-induced toxicities

Most patients with muscle-invasive bladder cancer (MIBC) are not cured with platinum chemotherapy. Up-regulation of nuclear factor kappa light-chain enhancer of activated B cells (NF-κB) is a major mechanism underlying chemoresistance, suggesting that its pharmacological inhibition may increase platinum efficacy. NF-κB signaling was investigated in two patient cohorts. The Cancer Genome Atlas (TCGA) was used to correlate NF-κB signaling and patient survival. The efficacy of cisplatin plus the NF-κB inhibitor dimethylaminoparthenolide (DMAPT) versus cisplatin or DMAPT alone was tested in vitro. Xenografted and immunocompetent MIBC mouse models were studied in vivo. Platinum-naive claudin-low MIBC showed constitutive NF-κB signaling and this was associated with reduced disease-specific survival in TCGA patients. Chemotherapy up-regulated NF-κB signaling and chemoresistance-associated genes, including SPHK1, PLAUR, and SERPINE1. In mice, DMAPT significantly improved the efficacy of cisplatin in both models. The combination preserved body weight, renal function, and morphology, reduced muscle fatigue and IL-6 serum levels, and did not aggravate immuno-hematological toxicity compared with cisplatin alone. These data provide a rationale for combining NF-κB inhibition with platinum-based chemotherapy and conducting a clinical trial in MIBC patients.

Expression of Luteinizing Hormone-Releasing Hormone (LHRH) and Type-I LHRH Receptor in Transitional Cell Carcinoma Type of Human Bladder Cancer

Bladder cancer (BC) is the tenth most frequently detected cancer in both sexes. Type-I luteinizing hormone-releasing hormone (LHRH) receptor (LHRH-R-I) is expressed not only in the pituitary, but also in several types of cancer disease. There are few data about LHRH-R-I expression in human BC. This study aimed to investigate the expression of LHRH and LHRH-R-I in the transitional cell carcinoma (TCC) type of human BC. RNA was extracted from 24 human bladder tumor specimens and three BC cell lines. RT-PCR was performed to detect mRNA for LHRH and LHRH-R-I. The protein of LHRH-R-I was further studied by immunohistochemistry (IHC), ligand competition assay, and Western Blot. PCR products of LHRH were found in 19 of 24 (79%) specimens and mRNA of LHRH-R-I was detected in 20 of 24 specimens (83%). Positive immunostaining for LHRH-R-I with different expression intensity was found in all samples examined, showing negative correlation with TCC grade. Radioligand binding studies also showed the presence of specific LHRH-R-I and high affinity binding of LHRH analogs. The high incidence of LHRH-R in BC suggests that it could serve as a molecular target for therapy of human BC with cytotoxic LHRH analogs or modern powerful antagonistic analogs of LHRH.

Development And In Vitro Characterization Of Bladder Tumor Cell Targeted Lipid-Coated Polyplex For Dual Delivery Of Plasmids And Small Molecules

BACKGROUND

Bladder cancer is the fourth most common cancer in men and eleventh most common in women. Combination therapy using a gene and chemotherapeutic drug is a potentially useful strategy for treating bladder cancer in cases where a synergistic benefit can be achieved successfully. This approach relies on developing drug combinations using carrier systems that can load both hydrophilic genes and hydrophobic drugs. Ideally, the formulation for carrier system should be free of traditional high shear techniques such as sonication and extrusion to reduce shear-induced nucleic acid strand breakage. Moreover, the system should be able to protect the nucleic acid from enzymatic attack and deliver it specifically to the tumor site.

MATERIALS AND METHODS

A dual payload carrier system that was formulated using a simple flow mixing technique to complex anionic plasmid (EGFP-NLS) using a cationic polymer (CD-PEI2.5kD) followed by coating of the polyplex using lipid membranes. The resulting lipid-coated polyplex (LCP) formulations are targeted to bladder cancer cells by employing a bacterial adhesive peptide sequence, RWFV, that targets the LCP to the tumor stroma for efficiently delivering reporter plasmid, EGFP-NLS and a model small molecule drug, pyrene, to the cancer cells.

RESULTS

Encapsulation efficiency of the peptide targeted carrier for the plasmid was 50% ± 0.4% and for pyrene it was 16% ± 0.4%. The ability of the targeted LCP to transfect murine bladder cancer cells was 4-fold higher than LCP bearing a scrambled peptide sequence. Fluorescence of cells due to pyrene delivery was highest after 4 hrs using targeted LCP. Finally, we loaded the peptide targeted LCP with anti-cancer agent, curcumin. The targeted formulation of curcumin resulted in only 45% viable cancer cells at a concentration of 5 µg/mL, whereas the empty and non-targeted formulations did not result any significant cell death.

CONCLUSION

These results demonstrate the specificity of the targeting peptide sequence in engaging tumor cells and the utility of the developed carrier platform to deliver a dual payload to bladder tumor cells.

Epidermal Growth Factor Receptor (EGFR) Cell Expression During Adjuvant Treatment After Transurethral Resection for Non-Muscle-Invasive Bladder Cancer: A New Potential Tool to Identify Patients at Higher Risk of Disease Progression

BACKGROUND

The aim of the study was to investigate the feasibility of Epidermal Growth Factor Receptor (EGFR) measurement in bladder washings of patients affected by non-muscle-invasive bladder cancer (NMIBC) and its prognostic role in identifying risk subgroups and predicting disease recurrence and progression.

PATIENTS AND METHODS

Patients with NMIBC treated with transurethral resection of bladder tumor (TURBT) from 2012 to 2015 were enrolled. Samples of bladder washings were collected and stored at -80°C until RNA extraction. The cDNA obtained from RNA was used to perform a gene expression analysis by a real time polymerase chain reaction.

RESULTS

An adequate cellular pellet was obtained in 50 (86.2%) of 58 patients and in 18 (85.7%) of 21 controls. Patients had a median 2.5-, a 1.6- and a 2.8-fold EGFR expression compared with controls before, during, and after adjuvant treatment, respectively. Patients at higher risk had a significantly higher EGFR expression compared with patients at low and intermediate risk when EGFR was measured during (P = .04) and after (P = .001) adjuvant therapy. At a median follow-up of 35.5 months (interquartile range, 19.0-54.8 months), in the high-risk group, patients with overexpression had a significantly lower recurrence-free survival (27.9% vs. 58%), progression-free survival (75.9% vs. 90.2%), and cancer-specific survival (77.7% vs. 93.3%). At multivariable analysis, EGFR overexpression was an additional independent prognostic factor to the European Organisation for Research and Treatment of Cancer scoring system of disease recurrence (hazard ratio, 1.98; 95% confidence interval, 1.32-2.97) and progression (hazard ratio, 1.84; 95% confidence interval, 1.27-2.65).

CONCLUSIONS

EGFR overexpression might represent an additional parameter to the current clinical tools for an individualized risk stratification.

Reversine induces autophagic cell death through the AMP-activated protein kinase pathway in urothelial carcinoma cells

Urothelial carcinoma is one of the most common malignancies of the urinary tract. Effective treatment of advanced urothelial carcinoma remains a clinical challenge with poor outcomes in these patients. Previous reports have shown that the expression of aurora kinase is associated with clinical stage and prognosis; hence, aurora kinases are potential targets in urothelial carcinoma therapy. Reversine, an aurora kinase inhibitor, was analyzed for its cytotoxicity in this study. Cell proliferation, flow cytometry, western blotting, and immunofluorescent assay were used to determine the effect of reversine on urothelial carcinoma cells. The results showed that reversine significantly inhibits the growth of urothelial carcinoma cell lines. Reversine induced cell cycle arrest at the G2/M phase, leading to autophagic cell death by activating the AMP-activated protein kinase pathway. Reversine induced significant cell death in urothelial carcinoma cells. Our results suggest that reversine may be a suitably small molecule for treating urothelial carcinoma in the future.

Epigenetic therapy in urologic cancers: an update on clinical trials

Epigenetic dysregulation is one of many factors that contribute to cancer development and progression. Numerous epigenetic alterations have been identified in urologic cancers including histone modifications, DNA methylation changes, and microRNA expression. Since these changes are reversible, efforts are being made to develop epigenetic drugs that restore the normal epigenetic patterns of cells, and many clinical trials are already underway to test their clinical potential. In this review we analyze multiple clinical trials (n=51) that test the efficacy of these drugs in patients with urologic cancers. The most frequently used epigenetic drugs were histone deacetylase inhibitors followed by antisense oligonucleotides, DNA methyltransferase inhibitors and histone demethylase inhibitors, the last of which are only being tested in prostate cancer. In more than 50% of the clinical trials considered, epigenetic drugs were used as part of combination therapy, which achieved the best results. The epigenetic regulation of some cancers is still matter of research but will undoubtedly open a window to new therapeutic approaches in the era of personalized medicine. The future of therapy for urological malignancies is likely to include multidrug regimens in which epigenetic modifying drugs will play an important role.

Emodin enhances cisplatin-induced cytotoxicity in human bladder cancer cells through ROS elevation and MRP1 downregulation

Background

Chemoresistance is one of the most leading causes for tumor progression and recurrence of bladder cancer. Reactive oxygen species (ROS) plays a key role in the chemosensitivity of cancer cells. In the present study, emodin (1,3,8-trihydroxy-6-methylanthraquinone) was applied as a ROS generator in combination with cisplatin in T24 and J82 human bladder cancer cells.

Methods

Cell viability and apoptosis rate of different treatment groups were detected by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and flow cytometry (FCM). The expression of transporters was measured at both the transcription and translation levels using PCR and western blotting. In vitro findings were confirmed by in vivo experiments using tumor-bearing mice. The expression of multidrug resistance-associated protein 1 (MRP1) in tumour tissue was measured using immunohistochemistry and side effects of the emodin/cisplatin co-treatment were investigated by histological examination.

Results

Emodin increased the cellular ROS level and effectively enhanced the cisplatin-induced cytotoxicity of T24 and J82 human bladder cancer cells through decreasing glutathione-cisplatin (GSH-cisplatin) conjugates. It blocked the chemoresistance of T24 and J82 cells to cisplatin through suppressing the expression of MRP1. This effect was specific in T24 and J82 cells but not in HCV-29 normal bladder epithelial cells. Consistent with in vitro experiments, emodin/cisplatin co-treatment increased the cell apoptosis and repressed the MRP1 expression in xenograft tumors, and without obvious systemic toxicity.

Conclusions

This study revealed that emodin could increase the cisplatin-induced cytotoxicity against T24 and J82 cells via elevating the cellular ROS level and downregulating MRP1 expression. We suggest that emodin could serve as an effective adjuvant agent for the cisplatin-based chemotherapy of bladder cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2640-3) contains supplementary material, which is available to authorized users.

An integrin-targeting nanosystem as a carrier of the selenadiazole derivative to induce ROS-mediated apoptosis in bladder cancer cells, from rational design to action mechanisms

Herein an integrin-targeting nanosystem is rationally designed and used as a carrier of a selenadiazole derivative to induce ROS-mediated apoptosis in bladder cancer cells.

Impact of ERBB2 mutations on in vitro sensitivity of bladder cancer to lapatinib

Lapatinib, a dual tyrosine kinase inhibitor of ErbB1 and ErbB2, shows a clinical benefit in a subset of patients with advanced urothelial bladder cancer (UBC). We hypothesized that the corresponding gene, ERBB2, is affected by mutations in a subset of UBC and that these mutations impact ErbB2 function, signaling, UBC proliferation, gene expression, and predict response to lapatinib. We found ERBB2 mutations in 5 of 33 UBC cell lines (15%), all of which were derived from invasive or high grade tumors. Phosphorylation and activation of ErbB2 and its downstream pathways were markedly enhanced in mutated cell lines compared with the ERBB2 wild-type. In addition, the gene expression profile was distinct, specifically for genes encoding for proteins of the extracellular matrix. RT112 cells infected with ERBB2 mutants showed a particular growth pattern ("mini-foci"). Upon treatment with lapatinib, 93% of these "mini-foci" were reversed. The sensitivity to lapatinib was greatest among cell lines with ERBB2 mutations. In conclusion, ERBB2 mutations occur in a subset of UBC and impact proliferation, signaling, gene expression and predict a greater response to lapatinib. If confirmed in the clinical setting, this may lead the way toward personalized treatment of a subset of UBC.

International phase III trial assessing neoadjuvant cisplatin, methotrexate, and vinblastine chemotherapy for muscle-invasive bladder cancer: long-term results of the BA06 30894 trial

PURPOSE

This article presents the long-term results of the international multicenter randomized trial that investigated the use of neoadjuvant cisplatin, methotrexate, and vinblastine (CMV) chemotherapy in patients with muscle-invasive urothelial cancer of the bladder treated by cystectomy and/or radiotherapy. Nine hundred seventy-six patients were recruited between 1989 and 1995, and median follow-up is now 8.0 years.

PATIENTS AND METHODS

This was a randomized phase III trial of either no neoadjuvant chemotherapy or three cycles of CMV.

RESULTS

The previously reported possible survival advantage of CMV is now statistically significant at the 5% level. Results show a statistically significant 16% reduction in the risk of death (hazard ratio, 0.84; 95% CI, 0.72 to 0.99; P = .037, corresponding to an increase in 10-year survival from 30% to 36%) after CMV.

CONCLUSION

We conclude that CMV chemotherapy improves outcome as first-line adjunctive treatment for invasive bladder cancer. Two large randomized trials (by the Medical Research Council/European Organisation for Research and Treatment of Cancer and Southwest Oncology Group) have confirmed a statistically significant and clinically relevant survival benefit, and neoadjuvant chemotherapy followed by definitive local therapy should be viewed as state of the art, as compared with cystectomy or radiotherapy alone, for deeply invasive bladder cancer.