Long-term results of combined chemotherapy with gemcitabine and cisplatin for metastatic urothelial carcinomas

Non-invasive medical gas plasma augments bladder cancer cell toxicity in preclinical models and patient-derived tumor tissues

INTRODUCTION

Medical gas plasma therapy has been successfully applied to several types of cancer in preclinical models. First palliative tumor patients suffering from advanced head and neck cancer benefited from this novel therapeutic modality. The gas plasma-induced biological effects of reactive oxygen and nitrogen species (ROS/RNS) generated in the plasma gas phase result in oxidation-induced lethal damage to tumor cells.

OBJECTIVES

This study aimed to verify these anti-tumor effects of gas plasma exposure on urinary bladder cancer.

METHODS

2D cell culture models, 3D tumor spheroids, 3D vascularized tumors grown on the chicken chorion-allantois-membrane (CAM) in ovo, and patient-derived primary cancer tissue gas plasma-treated ex vivo were used.

RESULTS

Gas plasma treatment led to oxidation, growth retardation, motility inhibition, and cell death in 2D and 3D tumor models. A marked decline in tumor growth was also observed in the tumors grown in ovo. In addition, results of gas plasma treatment on primary urothelial carcinoma tissues ex vivo highlighted the selective tumor-toxic effects as non-malignant tissue exposed to gas plasma was less affected. Whole-transcriptome gene expression analysis revealed downregulation of tumor-promoting fibroblast growth factor receptor 3 (FGFR3) accompanied by upregulation of apoptosis-inducing factor 2 (AIFm2), which plays a central role in caspase-independent cell death signaling.

CONCLUSION

Gas plasma treatment induced cytotoxicity in patient-derived cancer tissue and slowed tumor growth in an organoid model of urinary bladder carcinoma, along with less severe effects in non-malignant tissues. Studies on the potential clinical benefits of this local and safe ROS therapy are awaited.

Non coding RNAs as the critical factors in chemo resistance of bladder tumor cells

BACKGROUND

Bladder cancer (BCa) is the ninth frequent and 13th leading cause of cancer related deaths in the world which is mainly observed among men. There is a declining mortality rates in developed countries. Although, the majority of BCa patients present Non-Muscle-Invasive Bladder Cancer (NMIBC) tumors, only 30% of patients suffer from muscle invasion and distant metastases. Radical cystoprostatectomy, radiation, and chemotherapy have proven to be efficient in metastatic tumors. However, tumor relapse is observed in a noticeable ratio of patients following the chemotherapeutic treatment. Non-coding RNAs (ncRNAs) are important factors during tumor progression and chemo resistance which can be used as diagnostic and prognostic biomarkers of BCa.

MAIN BODY

In present review we summarized all of the lncRNAs and miRNAs associated with chemotherapeutic resistance in bladder tumor cells.

CONCLUSIONS

This review paves the way of introducing a prognostic panel of ncRNAs for the BCa patients which can be useful to select a proper drug based on the lncRNA profiles of patients to reduce the cytotoxic effects of chemotherapy in such patients.

5-Fluorouracil-based adjuvant chemotherapy improves the clinical outcomes of patients with lymphovascular invasion of upper urinary tract cancer and low expression of dihydropyrimidine dehydrogenase

Lymphovascular invasion (LVI) by urothelial carcinoma of the upper urinary tract (UC-UUT) is associated with an unfavorable prognosis. However, a high proportion of patients with UC-UUT are unable to receive the recommended doses of cisplatin-based adjuvant chemotherapy due to advanced age or renal dysfunction resulting from nephroureterectomy. Tegafur-uracil is an oral form of 5-fluorouracil whose efficacy is influenced by the activities of enzymes associated with its metabolism, such as dihydropyrimidine dehydrogenase (DPD), orotatephosphoribosyltransferase (OPRT) and thymidylate synthase (TS). The aim of the present study was to investigate the efficacy of adjuvant 5-fluorouracil chemotherapy for UC-UUT with LVI, and to assess the expression of enzymes associated with 5-fluorouracil metabolism as promising biomarkers of therapy efficacy. The present study retrospectively investigated 52 cases of UC-UUT. Following nephroureterectomy, tegafur-uracil was administered to 15 out of 30 patients with LVI who were not eligible for cisplatin-based adjuvant chemotherapy. Levels of DPD, OPRT and TS expression in tumor specimens were determined by reverse transcription-quantitative polymerase chain reaction, and their associations with the efficacy of adjuvant 5-fluorouracil chemotherapy were analyzed. The levels of DPD, OPRT and TS expression were not associated with pathological factors or outcome, although a higher expression of TS was associated with a poorer outcome. Adjuvant 5-fluorouracil chemotherapy significantly improved the outcome of patients with lower DPD expression. However, the levels of OPRT and TS expression did not influence therapeutic efficacy. Adjuvant 5-fluorouracil chemotherapy appears to be effective for lymphovascular-invasive UC-UUT in patients with lower DPD expression.

[PREDICTIVE AND PROGNOSTIC SIGNIFICANCE OF PRE-TREATMENT LYMPHOCYTE COUNT IN PATIENTS WITH METASTATIC UROTHELIAL CARCINOMA TREATED WITH PLATINUM-BASED FIRST-LINE CHEMOTHERAPY]

(Purpose) Pre-treatment low lymphocyte count may result from cytokine secretion by the tumor microenvironment, in association with aggressive tumor biology. We sought to establish the prognostic impact of the absolute lymphocyte count (ALC) in advanced urothelial carcinoma. (Patients and method) We retrospectively reviewed 63 patients with unresectable or metastatic urothelial carcinoma who were treated with platinum-based first-line systemic chemotherapy between January 2011 and April 2018. We evaluated the importance of the ALC in patients who underwent systematic chemotherapy. (Results) Thirty-eight patients (60%) died from urothelial carcinoma, with a median follow-up interval of 12.2 months. The median overall survival (OS) duration was 15.3 months. The mean ALC in the stable and progressive disease group was lower than that in the complete and partial response group (1,312 /μL and 1,666 /μL, respectively, p=0.004). The ALC of 1,460 /μL was determined as the cut-off on Receiver operating characteristic curve analysis. The log-rank test revealed that the lymphocytopenia group (ALC <1,460 /μL) showed significantly poorer prognoses than the non-lymphocytopenia group (p=0.001). Multivariate analyses showed that lymphocytopenia was an independent poor prognostic factor (hazard ratios of 3.46, p=0.002). (Conclusions) Pre-treatment low lymphocyte count is an independent poor prognostic factor in patients with urothelial carcinoma who underwent platinum-based first-line systemic chemotherapy.

Silencing of ECHDC1 inhibits growth of gemcitabine-resistant bladder cancer cells

Combined gemcitabine and cisplatin (GC) treatment is a first line chemotherapy for bladder cancer. However, acquired resistance to GC has been a major problem. To address the mechanism of gemcitabine resistance, and to identify potential biomarkers or target proteins for its therapy, we aimed to identify candidate proteins associated with gemcitabine resistance using proteomic analysis. We established gemcitabine-resistant human bladder cancer cell lines (UMUC3GR and HT1376GR) from gemcitabine-sensitive human bladder cancer cell lines (UMUC3 and HT1376). We compared the protein expression of parental and gemcitabine-resistant cell lines using isobaric tags for relative and absolute quantification (iTRAQ) and liquid chromatography tandem mass spectrometry. Among the identified proteins, ethylmalonyl-CoA decarboxylase (ECHDC1) expression was significantly increased in both of the gemcitabine-resistant cell lines compared to the respective parental cell lines. Silencing of ECHDC1 reduced ECHDC1 expression and significantly inhibited the proliferation of UMUC3GR cells. Furthermore, silencing of ECHDC1 induced upregulation of p27, which is critical for cell cycle arrest in the G1 phase, and induced G1 arrest. In conclusion, ECHDC1 expression is increased in gemcitabine-resistant bladder cancer cells, and is involved in their cell growth. ECHDC1, which is a metabolite proofreading enzyme, may be a novel potential target for gemcitabine-resistant bladder cancer therapy.

MicroRNA-218 Increases the Sensitivity of Bladder Cancer to Cisplatin by Targeting Glut1

Background/Aims: MicroRNA-218 (miR-218) is down-regulated in many malignancies that have been implicated in the regulation of diverse processes in cancer cells. However, the involvement of miR-218 in chemo-sensitivity to cisplatin and the precise mechanism of this action remained unknown in bladder cancer. Methods: qRT-PCR was used to detect miR-218 and its target Glut1 expression in bladder cancer cell lines T24 and EJ. CCK-8 method was utilized to measure the cell viability. IC 50 was calculated via a probit regression model. Glut1 was detected by western blotting for analysis of potential mechanism. Luciferase reporter assay was utilized to validate Glut1 as a direct target gene of miR-218. The intracellular level of GSH and ROS were determined using a commercial colorimetric assay kit and 2’, 7’-dichlorodihydro-fluorescein diacetate, respectively. Results: Over-expression of miR-218 significantly reduced the rate of glucose uptake and total level of GSH and enhanced the chemo-sensitivity of bladder cancer to cisplatin. Mechanistically, Glut1 was found to be a direct and functional target of miR-218. Up-regulation of Glut1 could restore chemo-resistance in T24 and EJ cells. On the contrary, knockdown of Glut1 could generate a similar effect as up-regulating the expression of miR-218. Conclusions: MiR-218 increases the sensitivity of bladder cancer to cisplatin by targeting Glut1. Restoration of miR-218 and repression of glut1 may provide a potential strategy to restore chemo-sensitivity in bladder cancer.

Comparison of single agent versus combined chemotherapy in previously treated patients with advanced urothelial carcinoma: a meta-analysis

Background

Platinum-based chemotherapy is the standard treatment for advanced urothelial cancer (UC) and is generally used in the first-line setting. However, the optimal salvage treatment for previously treated UC patients is unclear. We conducted a systematic review of published clinical trials of single agent versus combined chemotherapy as salvage treatment in previously treated UC patients.

Methods

Trials published between 1994 and 2015 were identified by an electronic search of public databases (MEDLINE, EMBASE, Cochrane library). All relevant studies were independently identified by two authors for inclusion. Demographic data, treatment regimens, objective response rate (ORR), disease control rate (DCR), median progression-free and overall survival (PFS, OS), and grade 3/4 toxicities were extracted and analyzed using Comprehensive Meta Analysis software (Version 2.0).

Results

Fifty cohorts with 1,685 patients were included for analysis: 814 patients were treated with single agent chemotherapy and 871 with combined chemotherapy. Pooled OS was significantly higher at 1 year for combined chemotherapy than for single agent (relative risk [RR] 1.52; 95% CI: 1.01–2.37; P=0.03) but not for 2-year OS (RR 1.31; 95% CI: 0.92–1.85; P=0.064). Additionally, combined chemotherapy significantly improved ORR (RR 2.25; 95% CI: 1.60–3.18; P<0.001) and DCR (RR 1.12; 95% CI: 1.01–1.25, P=0.033) compared to single agent for advanced UC patients. As for grade 3 and 4 toxicities, more frequencies of leukopenia and thrombocytopenia were observed in the combined chemotherapy than in single agent group, while equivalent frequencies of anemia, nausea, vomiting, and diarrhea were found between the two groups.

Conclusion

In comparison with single agent alone, combined chemotherapy as salvage treatment for advanced UC patients significantly improved ORR, DCR, and 1-year OS, but not 2-year OS. Our findings support the need to compare combined chemotherapy with single agent alone in the salvage setting in large prospective trials due to its potential survival benefit in advanced UC patients.

Maspin enhances cisplatin chemosensitivity in bladder cancer T24 and 5637 cells and correlates with prognosis of muscle-invasive bladder cancer patients receiving cisplatin based neoadjuvant chemotherapy

Background

Maspin, a non-inhibitory member of the serine protease inhibitor superfamily, has been characterized as a tumor suppressor gene in multiple cancer types. Chemotherapeutic insensitivity is one of major obstacles to effectively treating muscle invasive bladder cancer (MIBC). This study was conducted to investigate the role and probable mechanism of Maspin enhancing cisplatin chemosensitivity of bladder cancer in vitro and MIBC patients.

Methods

Maspin expression was quantified by qRT-PCR in two MIBC cell lines (T24 and 5637). After successful established Maspin overexpression model by lipidosome transfection, MTT and cell apoptosis assay were used to assess the MIBC’s cisplatin sensitivity. Western blot method was used to test PI3K/ AKT/mTOR signal passway and apoptosis related molecules Caspase3 and Bcl-2. Additionally, we evaluated Maspin expression and prognosis in 62 MIBC cases who underwent cisplatin based neoadjuvant chemotherapy (NACT) using immunohistochemistry.

Result

Upregulate Maspin expression could enhance the chemosensitivity induced by cisplatin in T24 and 5637 cell lines. The cell viability, cloning ability and IC50 were reduced while apoptosis rate was upregulated when cells were transfected Maspin. Phospho(p)-AKT, PI3K, mTOR, and Bcl-2 expression were significantly decreased, whereas Caspase3 was greatly increased in the Maspin group. In the clinic study, there was significant correlation between Maspin expression and overall survival (OS) and progression-free survival (PFS) rate in MIBC patients who received cisplatin based NACT.

Conclusion

Maspin could enhance cisplatin chemosensitivity in T24 and 5637 cell lines. Its expression correlated with prognosis of MIBC patients who received cisplatin based neoadjuvant chemotherapy.

Do metastatic upper tract urothelial carcinoma and bladder carcinoma have similar clinical responses to systemic chemotherapy? A Japanese multi-institutional experience

OBJECTIVE

There has been no clear evidence supporting similar chemo-responses for upper and lower urothelial carcinomas.

METHODS

We conducted a multicenter retrospective cohort study to analyze urothelial carcinoma patients who underwent systemic chemotherapy at 17 centers from 2004 to 2010. A total of 298 patients with either urothelial carcinoma of the bladder (N = 151) or upper tract urothelial carcinoma (N = 147) were included. Differences in tumor location (urothelial carcinoma of the bladder vs. upper tract urothelial carcinoma) were evaluated in relation to the patient backgrounds and clinical responses to systemic chemotherapy.

RESULTS

Overall 216 patients were treated with cisplatin-based chemo-regimens (gemcitabine and cisplatin in 92, or methotrexate, vinblastine, adriamycin and cisplatin/methotrexate, epirubicin and cisplatin in 124). Among 186 initially metastatic patients, the incidences of lung metastasis and liver metastasis were 39.2 and 34.1%, respectively, in upper tract urothelial carcinoma patients, and were significantly higher than those with urothelial carcinoma of the bladder (22.4% for lung; 8.4% for liver metastasis). Among 112 post-surgical recurrent/metastatic patients, age was significantly higher and estimated glomerular filtration rate at baseline was significantly lower in upper tract urothelial carcinoma patients than those with urothelial carcinoma of the bladder. No significant differences were observed in overall clinical response rates for systemic chemotherapy between urothelial carcinoma of the bladder (45.8%) and upper tract urothelial carcinoma (38%) in initially metastatic patients or between urothelial carcinoma of the bladder (43.2%) and upper tract urothelial carcinoma (44.1%) in post-surgical recurrent/metastatic patients. Tumor location was not independently associated with cancer-specific survival in either initially metastatic or post-surgical recurrent/metastatic urothelial carcinoma patients.

CONCLUSIONS

No significant difference was observed in response rates of urothelial carcinoma of the bladder and upper tract urothelial carcinoma to systemic chemotherapy, suggesting that a similar chemo-regimen can be applied to metastatic urothelial carcinoma patients regardless of tumor location (upper vs. lower).

Targeting Hsp90 in urothelial carcinoma

Urothelial carcinoma, or transitional cell carcinoma, is the most common urologic malignancy that carries significant morbidity, mortality, recurrence risk and associated health care costs. Despite use of current chemotherapies and immunotherapies, long-term remission in patients with muscle-invasive or metastatic disease remains low, and disease recurrence is common. The molecular chaperone Heat Shock Protein-90 (Hsp90) may offer an ideal treatment target, as it is a critical signaling hub in urothelial carcinoma pathogenesis and potentiates chemoradiation. Preclinical testing with Hsp90 inhibitors has demonstrated reduced proliferation, enhanced apoptosis and synergism with chemotherapies and radiation. Despite promising preclinical data, clinical trials utilizing Hsp90 inhibitors for other malignancies had modest efficacy. Therefore, we propose that Hsp90 inhibition would best serve as an adjuvant treatment in advanced muscle-invasive or metastatic bladder cancers to potentiate other therapies. An overview of bladder cancer biology, current treatments, molecular targeted therapies, and the role for Hsp90 inhibitors in the treatment of urothelial carcinoma is the focus of this review.

miR-101 suppresses vascular endothelial growth factor C that inhibits migration and invasion and enhances cisplatin chemosensitivity of bladder cancer cells

Background

The microRNA miR-101 is downregulated in several cancers, including bladder cancer. However, miR-101’s role in the invasion, metastasis, and chemosensitivity of bladder cancer cells remains unclear. This study was conducted to determine miR-101’s role on the lymphangiogenic molecule vascular endothelial growth factor C (VEGF-C) and their effects upon bladder cancer cell migration, invasion, and chemosensitivity to cisplatin.

Methods

Two bladder cancer cell lines (T24 and 5637) and the tool cell line 293T were employed here. Bladder cancer cells were transfected with either a miR-101 overexpression vector or a scrambled-sequence lentivirus, both of which exhibited a high transfection efficiency. Non-transfection was used as a mock negative control. Wound healing and Transwell assays were performed to measure cell migration and invasiveness. A luciferase reporter assay was performed to validate miR-101’s interaction with VEGF-C’s 3′ untranslated region followed by RT-PCR and Western blot confirmation. An MTS assay was used to evaluate the cisplatin sensitivity of the cell lines.

Results

miR-101 overexpression significantly inhibited the migration and invasiveness while significantly enhancing cisplatin sensitivity. miR-101 negatively regulated VEGF-C protein expression, and VEGF-C overexpression rescued the effects of miR-101 overexpression, indicating that miR-101 negatively regulates VEGF-C protein expression post-transcriptionally. miR-101 and VEGF-C interference independently enhanced cisplatin cytotoxicity in bladder cancer cells.

Conclusions

miR-101 suppresses VEGF-C expression, inhibits cell migration and invasion, and increases cisplatin sensitivity in bladder cancer cells. This study provides new insight into miR-101’s role in bladder cancer and shows miR-101’s promise as a potential molecular target for bladder cancer.

Remarkable response to neoadjuvant therapy with methotrexate, vinblastine, adriamycin, and Cisplatin for undifferentiated bladder carcinoma: a case report and literature review

We report a case of primary undifferentiated bladder carcinoma, which revealed a remarkable response to methotrexate, vinblastine, adriamycin, and cisplatin (MVAC) therapy. A 46-year-old Japanese woman presented at the hospital with the chief complaints of gross hematuria and pain during urination. Cystoscopy revealed a large smooth-surfaced tumor in the urinary bladder. The histopathological diagnosis was undifferentiated carcinoma. The patient then received 3 courses of MVAC over a 3-month period. Hydronephrosis disappeared after the first course, and the tumor shrank rapidly. After completion of the third MVAC course, radical cystectomy and ileal conduit surgery were performed. After 7 years, the patient has still had no recurrences or metastases. We retrospectively review the relative efficacy of the two popular chemotherapeutic regimens in the management of muscle-invasive bladder cancer in patients who had had radical cystectomy.

Evidenced-based clinical practice guideline for upper tract urothelial carcinoma (summary--Japanese Urological Association, 2014 edition)

Upper tract urothelial carcinoma is more rare than bladder cancer, although they are both categorized as urothelial carcinoma. Because of the low incidence, little clinical evidence is available regarding the treatment of the former. However, recently such evidence has slowly begun to accumulate. The guideline presented herein was compiled for the purpose of ensuring proper diagnosis and treatment by physicians involved in the treatment of upper tract urothelial carcinoma. We carefully selected 16 clinical questions essential for daily clinical practice and grouped them into four major categories: epidemiology, diagnosis, surgery and systemic chemotherapy/other matters. Related literature was searched using PubMed and Japan Medical Abstracts Society databases for articles published between 1987 and 2013. If the judgment was made on the basis of insufficient or inadequate evidence, the grade of recommendation was determined on the basis of committee discussions and resultant consensus statements. Here, we present a short English version of the original guideline, and overview its key clinical issues.

Cisplatin resistance by induction of aldo-keto reductase family 1 member C2 in human bladder cancer cells

Cisplatin is currently the most effective anti-tumor agent available against bladder cancer. To clarify the mechanism underlying cisplatin resistance in bladder cancer, the present study examined the role of the aldo-keto reductase family 1 member C2 (AKR1C2) protein on chemoresistance using a human bladder cancer cell line. The function of AKR1C2 in chemoresistance was studied using the human HT1376 bladder cancer cell line and the cisplatin-resistant HT1376-CisR subline. AKR1C2 was expressed in HT1376-CisR cells, but not in the parental cells. The effect of small interfering (si) RNAs and an inhibitor targeting AKR1C2 was examined to determine whether cisplatin sensitivity can be rescued by blocking AKR1C2 expression or function. Silencing of AKR1C2 mRNA or inhibition of AKR1C2 by 5β-cholanic acid resulted in a decrease in the survival of cells following cisplatin exposure. Intracellular accumulation of reactive oxygen species (ROS) was determined using a 2,7-dichlorodihydrofluorescein diacetate (H₂DCFDA) fluorescent probe. Cisplatin exposure increased the level of intracellular ROS in HT1376 cells in a dose-dependent manner. The ROS levels in HT1376-CisR cells were significantly lower than those in HT1376 cells and knockdown of AKR1C2 mRNA significantly restored ROS levels. Cisplatin exposure did not increase intracellular ROS in HT1376-CisR cells, although the level of intracellular ROS increased in HT1376 cells following cisplatin exposure. Silencing of AKR1C2 mRNA restored the ROS increase response to cisplatin and menadione as an oxidative stressor in HT1376-CisR cells. Menadione has the function of an oxidative stressor. The silencing of AKR1C2 mRNA restored the increased ROS response to cisplatin and menadione in HT1376-CisR cells. These results indicate that induction of AKR1C2 in human bladder cancer cells aids in the development of cisplatin resistance through antioxidative effects. The results of this study indicate that AKR1C2 may be an effective molecular target for restoring cisplatin resistance.

[Pathological complete response to gemcitabine and cisplatin chemotherapy for advanced upper tract urothelial carcinoma: a case report]

A 61-year-old man was referred to our hospital with the chief complaint of right leg weakness. Abdominal magnetic resonance imaging (MRI) and computed tomography (CT) demonstrated a ureteral tumor and a neighboring massive retroperitoneal tumor in addition to retroperitoneal lymph node and right renal metastases. The tumor was diagnosed as upper tract urothelial carcinoma (cT4N1M1) by percutaneous tumor biopsy. As the patient achieved a partial response after three courses of combination chemotherapy with gemcitabine and cisplatin, he received total nephroureterectomy and lymph node dissection. The pathology showed no viable cancer cells, demonstrating a pathological complete response. He remains alive after 26 months with no evidence of disease.

Combined chemotherapy with gemcitabine and carboplatin for metastatic urothelial carcinomas in patients with high renal insufficiency

BACKGROUND

This was a retrospective study to evaluate the activity and toxicity of a combined chemotherapeutic regimen of gemcitabine and carboplatin (GCa) in patients with metastatic urothelial carcinomas (UCs) with special regard to patients with highly impaired renal function.

METHODS

Eleven patients whose creatinine clearance was 30 ml/min or under and who had been diagnosed with metastatic UC were treated with GCa. The patient cohort comprised 4 males and 7 females, with a median age of 74 (range 67-84) years. The median follow-up was 19 (range 1-58) months.

RESULTS

Five of the 11 patients (45%) showed an objective response, with 2 achieving a clinically complete response and 3 a partial response with GCa. The grade 3/4 toxicity of the regimen was primarily hematological, including anemia (55%), neutropenia (45%), and thrombocytopenia (45%). Four patients (36%) could not complete the treatment in total. Grade 3 pneumonitis was found in one patient, and the treatment was terminated. Grade 4 febrile neutropenia occurred in the patient on hemodialysis, and the patient was forced to discontinue the chemotherapy. Another 2 patients also called off the treatment due to a pulmonary adverse event and an elevation of serum creatinine, respectively.

CONCLUSIONS

GCa appears to be effective for the treatment of metastatic UCs in patients with impaired renal function, but it is necessary to pay attention to the occurrence of severe adverse events.

Adseverin: a novel cisplatin-resistant marker in the human bladder cancer cell line HT1376 identified by quantitative proteomic analysis

Cisplatin is currently the most effective antitumor agent available against bladder cancer. However, a majority of patients eventually relapse with cisplatin-resistant disease. Chemoresistance thus remains a major obstacle in bladder cancer therapy. To clarify the molecular mechanisms underlying cisplatin resistance in bladder cancer, we established a cisplatin-resistant subline from the human bladder cancer cell line HT1376 (HT1376-CisR), and conducted large-scale analyses of the expressed proteins using two-dimensional (2D) gel electrophoresis coupled with mass spectrometry (MS). Comparative proteomic analysis of HT1376 and HT1376-CisR cells revealed 36 differentially expressed proteins, wherein 21 proteins were upregulated and 15 were downregulated in HT1376-CisR cells. Among the differentially regulated proteins, adseverin (SCIN), a calcium-dependent actin-binding protein, was overexpressed (4-fold upregulation) in HT1376-CisR, with the increase being more prominent in the mitochondrial fraction than in the cytosol fraction. SCIN mRNA knockdown significantly reduced cell proliferation with mitochondria-mediated apoptosis in HT1376-CisR cells. Immunoprecipitation analysis revealed voltage-dependent anion channels (VDACs) to be bound to SCIN in the mitochondrial fraction. Our results suggest that the VDAC-SCIN interaction may inhibit mitochondria-mediated apoptosis in cisplatin-resistant cells. Targeting the VDAC-SCIN interaction may offer a new therapeutic strategy for cisplatin-resistant bladder cancer.