OP-071 Expression of Cell Cycle-associated Proteins in Non-muscle Invasive Bladder Cancer : Correlation with Intravesical Recurrence Following TUR

4512 Background: Biomarkers of survival and resistance in chemotherapy-resistant muscle-invasive bladder cancer (MIBC) are not well-characterized, but may inform management in this setting. Methods: Matched pre- and post-neoadjuvant cisplatin-based chemotherapy (NAC) tumor samples were obtained from 30 MIBC patients with gross residual disease (≥ pT2) at cystectomy, followed by whole exome sequencing of these “trios” (pre- and post-NAC tumor with matched germline samples). Phylogenetic analysis of matched tumor samples was performed to identify subclones, their associated mutations, and the corresponding enrichment in post-treatment tumors. Intratumoral heterogeneity was assessed by the proportion of mutations that were subclonal; the number of inferred subclones; and associated with overall survival using a Cox Proportional Hazards model. Results: Increased proportion of subclonal mutations in post-treatment tumors was associated with worse overall survival (HRR 1.86 [95% CI 1.12-3.06], p = 0.02), whereas pre-treatment proportion of subclonal mutations was only borderline statistically significant (HRR 1.48 [95% CI 0.99-2.20], p = 0.052). The total number of inferred tumor subclones in pre- or post-treatment tumor (or both) was associated with overall survival (HRR 1.60 [95% CI 1.05-2.43], p = 0.03), interpreted as a 60% increase in death rate per additional inferred subclone. While no single gene was statistically significantly enriched for new alterations in the post-chemotherapy resistant samples, we observed new post-treatment amplifications in cell-cycle genes ( E2F3, c-JUN), biallelic events in cell-cycle regulators ( FBXW7), and amplification of immune checkpoint genes ( PDL1/2). Conclusions: These results suggest that intratumoral heterogeneity (particularly post-therapy) predicts survival in a chemotherapy-resistant cohort. Further, alterations in cell cycle regulation may contribute to the mechanism of chemotherapy resistance. Finally, we observe evidence of immune checkpoint gene amplification post-treatment, suggesting that testing immune checkpoint blockade during NAC or, in high risk patients, following NAC may be warranted.

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Evaluating cell cycle progression score as a prognostic marker for non-muscle invasive bladder cancer (NMIBC).

Journal of Clinical Oncology ◽

10.1200/jco.2018.36.6_suppl.476 ◽

2018 ◽

Vol 36 (6_suppl) ◽

pp. 476-476

Author(s):

Christopher J. Weight ◽

Paari J Murugan ◽

David Chesla ◽

Resha Tejpaul ◽

Ayman Soubra ◽

...

Keyword(s):

Cell Cycle ◽

Bladder Cancer ◽

Prognostic Marker ◽

Cell Cycle Progression ◽

Multivariable Analysis ◽

Invasive Bladder Cancer ◽

Prognostic Information ◽

Muscle Invasive Bladder Cancer ◽

Cycle Progression ◽

Muscle Invasive

476 Background: Accurate grading and staging from transurethral resection of bladder tumors (TURBT) is vital for appropriate clinical management. Non-muscle-invasive bladder cancer (NMIBC) can recur progress with higher grade and or stage progression to MIBC, requiring radical intervention with poorer prognosis. Further, grade and stage may change in 20-50% of TURBTs following re-review by expert GU pathologists Objective measures of stage and grade might offer additional and/or improved risk stratification; therefore we evaluated a molecular RNA signature as a prognostic marker for NMIBC. Methods: Patients were diagnosed with NMIBC at the University of Minnesota (UM)or Spectrum Health System(SHS) from 2005-2012. A Cell Cycle Progression (CCP) score was determined from the average expression of 36 CCP genes for patients with available FFPE diagnostic TURBT. The combined cohort consisted of 293 patients (UM n = 152, SHS n = 141). Study outcome was time from NMIBC diagnosis to progression to MIBC. Median follow-up for patients who did not experience an event was 4.4 years for UM and 6.9 for SHS. Association with outcomes was evaluated by Cox proportional hazards survival analysis and likelihood ratio tests. All analyses were stratified by cohort. Results: CCP score was associated with progression to MIBC in univariable analysis [hazard ratio 1.42 (95% CI 1.19, 1.68), p = 4.3x10-5]. Tumor grade and stage were also highly prognostic. CCP score was strongly associated with stage (T1 vs Ta, p < 10-6) and grade (high vs low, p < 10-14) in both cohorts. As a result, CCP score did not provide independent prognostic information in multivariable analysis after adjusting for stage and grade (p = 0.32). There was a significant interaction between stage and CCP score (p = 0.0017), justifying an exploratory analysis of CCP score in Ta disease. In this subset, CCP score trended toward (p = 0.056) after adjusting for grade. Conclusions: In NMIBC, CCP score was highly correlated with tumor stage and grade and could serve as a quantitative measure of clinical parameters. The score may also provide prognostic information regarding risk of progression to MIBC, particularly in patients with Ta disease, but requires additional validation.

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Obatoclax, a BH3 Mimetic, Enhances Cisplatin-Induced Apoptosis and Decreases the Clonogenicity of Muscle Invasive Bladder Cancer Cells via Mechanisms That Involve the Inhibition of Pro-Survival Molecules as Well as Cell Cycle Regulators

International Journal of Molecular Sciences ◽

10.3390/ijms20061285 ◽

2019 ◽

Vol 20 (6) ◽

pp. 1285 ◽

Cited By ~ 2

Author(s):

Thomas Steele ◽

George Talbott ◽

Anhao Sam ◽

Clifford Tepper ◽

Paramita Ghosh ◽

...

Keyword(s):

Cell Cycle ◽

Cell Proliferation ◽

Bladder Cancer ◽

Invasive Bladder Cancer ◽

Dependent Manner ◽

Cell Cycle Regulators ◽

Muscle Invasive Bladder Cancer ◽

Expression Levels ◽

Muscle Invasive ◽

Bh3 Mimetic

Several studies by our group and others have determined that expression levels of Bcl-2 and/or Bcl-xL, pro-survival molecules which are associated with chemoresistance, are elevated in patients with muscle invasive bladder cancer (MI-BC). The goal of this study was to determine whether combining Obatoclax, a BH3 mimetic which inhibits pro-survival Bcl-2 family members, can improve responses to cisplatin chemotherapy, the standard of care treatment for MI-BC. Three MI-BC cell lines (T24, TCCSuP, 5637) were treated with Obatoclax alone or in combination with cisplatin and/or pre-miR-34a, a molecule which we have previously shown to inhibit MI-BC cell proliferation via decreasing Cdk6 expression. Proliferation, clonogenic, and apoptosis assays confirmed that Obatoclax can decrease cell proliferation and promote apoptosis in a dose-dependent manner. Combination treatment experiments identified Obatoclax + cisplatin as the most effective treatment. Immunoprecipitation and Western analyses indicate that, in addition to being able to inhibit Bcl-2 and Bcl-xL, Obatoclax can also decrease cyclin D1 and Cdk4/6 expression levels. This has not previously been reported. The combined data demonstrate that Obatoclax can inhibit cell proliferation, promote apoptosis, and significantly enhance the effectiveness of cisplatin in MI-BC cells via mechanisms that likely involve the inhibition of both pro-survival molecules and cell cycle regulators.

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Prognostic Value of BUB1 for Predicting Non-Muscle-Invasive Bladder Cancer Progression

International Journal of Molecular Sciences ◽

10.3390/ijms222312756 ◽

2021 ◽

Vol 22 (23) ◽

pp. 12756

Author(s):

Xuan-Mei Piao ◽

Chaelin You ◽

Young Joon Byun ◽

Ho Won Kang ◽

Junho Noh ◽

...

Keyword(s):

Cell Cycle ◽

Bladder Cancer ◽

Cancer Cells ◽

Mitotic Checkpoint ◽

Invasive Bladder Cancer ◽

Common Disease ◽

Muscle Invasive Bladder Cancer ◽

Bladder Cancer Cells ◽

Muscle Invasive ◽

Normal Controls

Non-muscle-invasive bladder cancer (NMIBC) is a common disease with a high recurrence rate requiring lifetime surveillance. Although NMIBC is not life-threatening, it can progress to muscle-invasive bladder cancer (MIBC), a lethal form of the disease. The management of the two diseases differs, and patients with MIBC require aggressive treatments such as chemotherapy and radical cystectomy. NMIBC patients at a high risk of progression benefit from early immediate cystectomy. Thus, identifying concordant markers for accurate risk stratification is critical to predict the prognosis of NMIBC. Candidate genetic biomarkers associated with NMIBC prognosis were screened by RNA-sequencing of 24 tissue samples, including 16 NMIBC and eight normal controls, and by microarray analysis (GSE13507). Lastly, we selected and investigated a mitotic checkpoint serine/threonine kinase, BUB1, that regulates chromosome segregation during the cell cycle. BUB1 gene expression was tested in 86 NMIBC samples and 15 controls by real-time qPCR. The performance of BUB1 as a prognostic biomarker for NMIBC was validated in the internal Chungbuk cohort (GSE13507) and the external UROMOL cohort (E-MTAB-4321). BUB1 expression was higher in NMIBC patients than in normal controls (p < 0.05), and the overexpression of BUB1 was correlated with NMIBC progression (log-rank test, p = 0.007). In in vitro analyses, BUB1 promoted the proliferation of bladder cancer cells by accelerating the G2/M transition of the cell cycle. Conclusively, BUB1 modulates the G2/M transition to promote the proliferation of bladder cancer cells, suggesting that it could serve as a prognostic marker in NMIBC.

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