Targeted agents in second-line bladder cancer therapy

Anti-Proliferative Role of the Tyrosine Kinase Inhibitors TKI-258 on Oral Squamous Cell Carcinoma In Vitro

BACKGROUND

Identification of the antitumor role of tyrosine kinase inhibitors, such as TKI-258, may lead to novel therapeutics for Oral Squamous Cell Carcinoma (OSCC), which has high mortality rates. TKI-258 blocks Fibroblast Growth Factor Receptors (FGFRs), Platelet-Derived Growth Factor Receptors (PDGFRs), and Endothelial Growth Factor Receptor (VEGFRs).

OBJECTIVE

This study aimed to evaluate the effect of TKI-258 treatment on cell proliferation in SCC-4 cells of OSCC.

METHODS

BrdU and KI-67 assays were performed by using SCC-4 cells. Control was compared to 1, 5 and 10μM TKI-258 treatment. Control vehicle was compared to: 60μM LY294002 (LY), 2μM Wortmannin (WTN) and LY+WNT. Moreover, TKI 5μM treatment was compared to: TKI 5μM+LY; TKI 5 μM+WTN; TKI 5μM+LY+WTN. After 6h of treatments, immunofluorescence stained BrdU and KI-67 positive cells. Morphometry of proliferative cells was analyzed considering significance of p<0.05.

RESULTS

BrdU and KI-67 assays results were similar for all experiments. TKI-258 treatment leads to an important reduction in proliferation rate in SCC-4 cells in a concentration dependent manner. As expected, there was a significant reduction in the percentage of proliferative cells that had PI3K inhibited. When compared with TKI 5 treatment, proliferating cells were significantly lower with simultaneous PI3K inhibition.

CONCLUSION

This study demonstrated that TKI-258 plays an anti-proliferative role on SCC-4 cells of OSCC. It could be interesting to block multiples pathways such as FGFRs, PDGFRs and VEGFRs. Therefore, TKI-258 is a promising option for novel therapeutics for OSCC, especially if associated with PI3K inhibition.

Bladder Cancer: New Insights into Its Molecular Pathology

Bladder cancer is one of the most prevalent cancers worldwide. Unfortunately, there have been few advances in its clinical management due to a poor understanding of the correlations between its molecular and clinical features. Mounting evidence suggests that bladder cancer comprises a group of molecularly heterogeneous diseases that undergo a variety of clinical courses and possess diverse therapeutic responses. Owing to the close association between its molecular subtypes and clinicopathological features, specific therapeutic strategies have recently been suggested. This review summarizes the current understanding of the molecular pathology of bladder cancer, including its molecular biomarkers/pathways and molecular subtypes that have been newly identified using high-throughput technologies. It also discusses advances in our understanding of personalized treatments for specific molecular subtypes.

The role of pazopanib on tumour angiogenesis and in the management of cancers: A review

Pazopanib is a relatively new compound to be introduced into the chemotherapy field. It is thought to have decent anti-angiogenic properties, which gives an additional hope for the treatment of certain types of cancers. A systematic review solely discussing about pazopanib and its anti-angiogenic effect is yet to be published to date, despite several relevant clinical trials being conducted over the recent years. In this review, we aim to investigate the mechanism of pazopanib's anti-angiogenic effect and its effectiveness in treating several cancers. We have included, in this study, findings from electronically searchable data from randomized clinical trials, clinical studies, cohort studies and other relevant articles. A total of 352 studies were included in this review. From the studies, the effect of pazopanib in various cancers or models was observed and recorded. Study quality is indefinite, with a few decent quality articles. The most elaborately studied cancers include renal cell carcinoma, solid tumors, advanced solid tumors, soft tissue sarcoma, breast cancer and gynecological cancers. In addition, several less commonly studied cancers are included in the studies as well. Pazopanib had demonstrated its anti-angiogenic effect based on favorable results observed in cancers, which are caused by angiogenesis-related mechanisms, such as renal cell carcinoma, solid tumors, advanced solid tumors and soft tissue sarcoma. This review was conducted to study, analyze and review the anti-angiogenic properties of pazopanib in various cancers. The results obtained can provide a decent reference when considering treatment options for angiogenesis-related malignancies. Furthermore, the definite observations of the anti-angiogenic effects of pazopanib could provide newer insights leading to the future development of drugs of the same mechanism with increased efficiency and reduced adverse effects.

Vinflunine in the treatment of advanced urothelial cancer: clinical evidence and experience

Vinflunine (VFL) has been approved in Europe for second-line treatment of metastatic and advanced urothelial cancer after failure of platin-containing therapy. Since approval, the drug has been investigated in few clinical trials. Most of the currently available reports describe experiences with VFL in a daily clinical setting. This review gives a short overview on clinical experiences and clinical trials involving VFL since the approval of this drug in 2009.

Real-World Vinflunine Outcomes in Bladder Cancer in a Single-Institution Study: Moving Beyond Clinical Trials

PURPOSE

Intravenous vinflunine 320 mg/m(2) every 3 weeks plus best supportive care resulted in better overall survival in comparison with best supportive care alone for eligible patients with failure of prior therapy with locally advanced or metastatic transitional cell cancer of urothelial tract (TCCU). The objective of the present study was to describe our real-life experience of vinflunine for treatment of patients with TCCU.

PATIENTS AND METHODS

We retrospectively investigated all patients with TCCU who received at least 1 cycle of vinflunine.

RESULTS

Nineteen patients were treated between May 2010 and March 2014 in a compassionate-use program. Performance status was poor in our real-life cohort, with 6 patients (32%) with an Eastern Cooperative Oncology Group performance status of 2. Median duration of vinflunine treatment was 2.4 months (range, 0-4.3 months), and median number of cycles was 3 (range, 1-6). Total response rate was 32%, with partial responses only. Disease control rate was 53%, with a median duration of 7.7 months (range, 6.0-9.4 months). Median progression-free survival was 87 days, or 2.9 months (range, 0.7-11.7 months). After vinflunine treatment, 42% of patients received from 1 to 3 additional lines of chemotherapy. The most frequent grade 4 toxicities were constipation (26%), with 3 intestinal obstructions (16%) and 1 mechanical ileus (5%); and asthenia and fatigue (21%).

CONCLUSION

Vinflunine, as a TCCU second-line chemotherapy, brings benefits, particularly in cases where there is no alternative treatment.

[Systemic therapy of metastatic bladder cancer.]

This review focuses on current options in the medical therapy of metastasized urothelial carcinoma of the bladder. Standard treatments as well as new, recently published therapeutic approaches are evaluated and discussed.

Combined treatment with pazopanib and vinflunine in patients with advanced urothelial carcinoma refractory after first-line therapy

The role of pazopanib in the second-line setting of refractory metastatic transitional cell carcinoma of the urothelium has not been defined clearly. The aim of this phase I/II trial was to assess the safety, tolerability, and efficacy of combining pazopanib and vinflunine in patients with metastatic transitional cell carcinoma of the urothelium after failure of first-line platinum-containing therapy. From May 2011 to December 2011, five patients were enrolled in this trial. Pazopanib was the investigated compound; four levels were planned (200, 400, 600, and 800 mg/day). Vinflunine was dosed at 280 mg/m for the first dose and 320 mg/m every 3 weeks thereafter. After the definition of a tolerated dose for the combined therapy, a subsequent phase II study was planned. At the starting level, pazopanib 200 mg/day, dose-limiting toxicities were observed in two of five patients. One patient experienced grade 4 febrile neutropenia, which led to treatment discontinuation. A second patient showed grade 3 hepatobiliary disorder with an increase in γ-glutamyltransferase. The study was interrupted at dose level 1 for safety reasons. The initially planned phase II study was therefore not carried out. This phase I study showed that combined therapy of daily pazopanib (200 mg) and vinflunine (280/320 mg/m) every 3 weeks is poorly tolerated in patients with refractory advanced urothelial cancer.

Pazopanib and sunitinib trigger autophagic and non-autophagic death of bladder tumour cells

Background:

Tyrosine kinase inhibitors (TKI) such as sunitinib and pazopanib display their efficacy in a variety of solid tumours. However, their use in therapy is limited by the lack of evidence about the ability to induce cell death in cancer cells. Our aim was to evaluate cytotoxic effects induced by sunitinib and pazopanib in 5637 and J82 bladder cancer cell lines.

Methods:

Cell viability was tested by MTT assay. Autophagy was evaluated by western blot using anti-LC3 and anti-p62 antibodies, acridine orange staining and FACS analysis. Oxygen radical generation and necrosis were determined by FACS analysis using DCFDA and PI staining. Cathepsin B activation was evaluated by western blot and fluorogenic Z-Arg-Arg-AMC peptide. Finally, gene expression was performed using RT–PCR Profiler array.

Results:

We found that sunitinib treatment for 24 h triggers incomplete autophagy, impairs cathepsin B activation and stimulates a lysosomal-dependent necrosis. By contrast, treatment for 48 h with pazopanib induces cathepsin B activation and autophagic cell death, markedly reversed by CA074-Me and 3-MA, cathepsin B and autophagic inhibitors, respectively. Finally, pazopanib upregulates the α-glucosidase and downregulates the TP73 mRNA expression.

Conclusion:

Our results showing distinct cell death mechanisms activated by different TKIs, provide the biological basis for novel molecularly targeted approaches.