Current chemotherapeutic strategies against bladder cancer

Expressions of P-Glycoprotein, Multidrug Resistance Protein 1 and Annexin A2 as Predictive Factors for Intravesical Recurrence of Bladder Cancer after the Initial Transurethral Resection and Immediate Single Intravesical Instillation of Adriamycin

OBJECTIVE

Immediate single instillation of chemotherapy following transurethral resection of bladder tumor (TURBT) is suggested for non-muscle invasive bladder cancer (NMIBC) patients. However, no study has evaluated molecular marker that was involved in intravesical recurrence (IVR) after single instillation of chemotherapy. Therefore, this study aimed to evaluate whether P-glycoprotein, multidrug resistance protein 1 (MRP1), Annexin A2 (ANXA2) or nucleophosmin (NPM) expression predicts IVR after initial TURBT and immediate single intravesical adriamycin instillation.

METHODS

We retrospectively reviewed consecutive 443 patients who underwent TURBT. Of these, 54 patients who underwent initial TURBT and single instillation of adriamycin for NMIBC were included. The expressions of P-glycoprotein, MRP1, ANXA2 and NPM were evaluated immunohistochemically and were divided into 2 groups (low or high) according to the staining intensity and/or proportion of positive cells. IVR was assessed by Kaplan-Meier method. Cox`s multivaritate analyses were performed to identify independent predictors for IVR.

RESULTS

Nineteen patients (35.1%) had IVR. High P-glycoprotein expression was significantly correlated with multiplicity, pT stage and high grade. High ANXA2 expression was significantly correlated with high grade. MRP1 and NPM were not correlated with any clinicopathological variables. MRP1 expression and ANXA2 expression were significantly correlated with P-glycoprotein expression. Patients with high P-glycoprotein expression had significantly worse IVR-free survival (IVRFS) than those with low P-glycoprotein expression (P =0.015). The difference in IVRFS rates between patients with high ANXA2 expression and those with low ANXA2 expression was nearly significant (P =0.057). Univariate analyses indicated multiplicity, high grade and high P-glycoprotein expression were significant predictors for IVR. Multivariate analysis indicated high grade was an independent predictor for IVR.

CONCLUSIONS

High P-glycoprotein expression was associated with IVR. Further study was needed to determine significance of P-glycoprotein expression in IVR after single intravesical adriamycin instillation.

Use of treatment pathway improves neoadjuvant chemotherapy use in muscle-invasive bladder cancer

PURPOSE

To assess the trends of neoadjuvant chemotherapy (NAC) use since its introduction in our practice pathway in patients with cT2 + bladder cancer over a 20-year period.

METHODS

This is a retrospective review of patients with cT2 + bladder cancer who underwent RC between 01/01/1998 and 01/01/2018 that aimed to evaluate the trends of NAC use and associated after implementation of a multidisciplinary treatment pathway. Cohorts were stratified into eras: pre-NAC (1998-2007) to NAC eras (2008-2018). Univariate analysis was conducted using Chi-squared test and Kaplan-Meier estimates were used to evaluate survival.

RESULTS

In 904 total patients who underwent RC, there were 493 with cT2 + UCC disease. The rate of NAC peaked at 84.2% in the most recent year of analysis in all patients and was 100% in cT2 + patients eligible for NAC. There was an increased rate of complete response (downstage to pT0) from 8.7% to 15.8% (p = 0.018) between the two eras. Unadjusted survival analysis revealed improved overall survival (OS) between eras with 5-year OS 53.2% vs. 42.7% and 10-year OS 42.7% vs. 26.4% in the NAC vs. pre-NAC cohorts, respectively (p = 0.016).

CONCLUSIONS

In this review of 20 years of experience, we report a dramatic rise in the use of NAC after adoption of a multidisciplinary pathway that is associated with expected survival benefits.

Repression of GRIM19 expression potentiates cisplatin chemoresistance in advanced bladder cancer cells via disrupting ubiquitination-mediated Bcl-xL degradation

OBJECTIVE

The mainstay of treatment for advanced bladder cancer (BC) is cisplatin (CDDP)-based systematic chemotherapy. However, acquired chemoresistance induced by as yet unidentified mechanisms is encountered frequently and often results in treatment failure and disease progression. The present study was designed to elucidate the expression and potential role of the gene associated with retinoid-interferon-induced mortality-19 (GRIM19) in the pathogenesis of CDDP resistance in BC.

METHODS

RT-qPCR and immunoblotting were employed to evaluate the expression profile of GRIM19 in clinical BC samples and in different BC cells. Using cell viability assay, apoptotic ELISA, xenografts mouse model, and Transwell assay, the effects of GRIM19 inhibition or GRIM19 overexpression on CDDP resistance were determined in different BC cells. Lastly, using co-immunoprecipitation, we provided the molecular evidence for the interaction between GRIM19 and Bcl-xL.

RESULTS

Expression levels of GRIM19 were significantly down-regulated in recurrent BC specimens, and in experimentally induced CDDP-resistant BC cells. Functionally, overexpression of the exogenous GRIM19 potentiated CDDP sensitivity and suppressed the survival and invasion of BC cells in the presence of CDDP challenge. Mechanistically, the compromised CDDP chemosensitization induced by GRIM19 loss was at least partially attributed to the attenuation of Bcl-xL polyubiquitination and subsequent degradation, because (1) GRIM19 colocalized with Bcl-xL in the mitochondria of BC cells and (2) GRIM19 overexpression promoted the ubiquitination of Bcl-xL, and this event could be effectively reversed by pretreatment with inhibitors of p38-MAPK and JNK pathways, indicating that GRIM19 overexpression-induced Bcl-xL ubiquitination may achieve in a p38/JNK-dependent manner. Using the UMUC-3 cells stably depleted of endogenous GRIM19, we further show that inhibition of Bcl-xL rectified GRIM19 deficiency-caused CDDP resistance in BC cells. In addition, BCL2L1 mRNA levels were negatively correlated with GRIM19 mRNA levels in CDDP-associated clinical BC tissues.

CONCLUSIONS

Disruption of GRIM19/Bcl-xL is a key mechanism of CDDP resistance in advanced BC. Therapeutically, enhancement of GRIM19 expression or employment of p38/JNK inhibitors may serve as resensitizing therapies for subgroups of CDDP-resistant or refractory BC patients.

Flavagline analog FL3 induces cell cycle arrest in urothelial carcinoma cell of the bladder by inhibiting the Akt/PHB interaction to activate the GADD45α pathway

BACKGROUND

Prohibitin 1 (PHB) is a potential target for the treatment of urothelial carcinoma of the bladder (UCB). FL3 is a newly synthesized agent that inhibits cancer cell proliferation by targeting the PHB protein; however, the effect of FL3 in UCB cells remains unexplored.

METHODS

FL3 was identified to be a potent inhibitor of UCB cell viability using CCK-8 (cell counting kit-8) assay. Then a series of in vitro and in vivo experiments were conducted to further demonstrate the inhibitory effect of FL3 on UCB cell proliferation and to determine the underlying mechanisms.

RESULTS

FL3 inhibited UCB cell proliferation and growth both in vitro and in vivo. By targeting the PHB protein, FL3 inhibited the interaction of Akt and PHB as well as Akt-mediated PHB phosphorylation, which consequently decreases the localization of PHB in the mitochondria. In addition, FL3 treatment resulted in cell cycle arrest in the G2/M phase, and this inhibitory effect of FL3 could be mimicked by knockdown of PHB. Through the microarray analysis of mRNA expression after FL3 treatment and knockdown of PHB, we found that the mRNA expression of the growth arrest and DNA damage-inducible alpha (GADD45α) gene were significantly upregulated. When knocked down the expression of GADD45α, the inhibitory effect of FL3 on cell cycle was rescued, suggesting that FL3-induced cell cycle inhibition is GADD45α dependent.

CONCLUSION

Our data provide that FL3 inhibits the interaction of Akt and PHB, which in turn activates the GADD45α-dependent cell cycle inhibition in the G2/M phase.

Decreased expression of LncRNA MIR31HG in human bladder cancer

OBJECTIVE

In this study, we examined the relationships between the expression level of long non-coding RNA MIR31HG in bladder cancer and the clinical characteristics.

METHODS

A total of 55 tissue samples from patients with bladder cancer were collected, and the lncRNA MIR31HG levels in cancer, paired non-cancer tissues and BC cell lines were detected by real-time quantitative RT-PCR (qRT-PCR). The relationships between MIR31HG level and the clinical characteristics were evaluated.

RESULTS

MIR31HG expression was remarkably decreased in bladder cancer tissues compared with adjacent noncancerous tissues (P < 0.05). MIR31HG expression was also significantly down-regulated in four bladder cancer cell lines (P < 0.001). Clinicopathologic analysis revealed that MIR31HG expression was negatively associated with TNM stage (P = 0.010), but not with other clinicopathological characteristics.

CONCLUSIONS

These findings revealed that MIR31HG may function as a cancer-suppressor gene to participate in the bladder cancer carcinogenesis and development.

Choroidal and cutaneous metastasis from urothelial carcinoma of the bladder after radical cystectomy: a case report and literature review

Bladder cancer is the second most common genitourinary malignancy and has variable metastatic potential; however, choroidal and cutaneous metastases are extremely rare. Generally, a patient with these uncommon metastases has a very poor prognosis. We present a bladder cancer patient with a visual disorder in the right eye and multiple nodules on head and lower abdomen that developed 17 months after a radical cystectomy. These symptoms were determined to be caused by choroidal and cutaneous metastasis of bladder cancer. Although two cycles of combination chemotherapy were performed, the patient died 5 months after diagnosis of multiple metastases.