Second-line systemic therapies for metastatic urothelial carcinoma: a population-based cohort analysis

Platinum-Based Chemotherapy 'Rechallenge' in Advanced Non-ovarian Solid Malignancies

Platinum-based chemotherapy forms the backbone of treatment for many solid cancers. However, resistance inevitably develops in those with advanced disease. Platinum rechallenge is a well-established concept in the management of ovarian cancer, small cell lung cancer and germ cell tumours. In other solid malignancies there is a lack of quality evidence to support platinum rechallenge, yet it is a widely adopted strategy. Often, patients are within the last year of life, making questions of efficacy, treatment-related toxicity and quality of life critical factors for treatment recommendations. In this overview we appraise the available evidence for platinum rechallenge and strategies being developed to attempt resensitisation of tumours to platinum-based chemotherapy.

Targeted Inhibition of O-Linked β-N-Acetylglucosamine Transferase as a Promising Therapeutic Strategy to Restore Chemosensitivity and Attenuate Aggressive Tumor Traits in Chemoresistant Urothelial Carcinoma of the Bladder

Acquisition of acquired chemoresistance during treatment cycles in urothelial carcinoma of the bladder (UCB) is the major cause of death through enhancing the risk of cancer progression and metastasis. Elevated glucose flux through the abnormal upregulation of O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT) controls key signaling and metabolic pathways regulating diverse cancer cell phenotypes. This study showed that OGT expression levels in two human UCB cell models with acquired resistance to gemcitabine and paclitaxel were significantly upregulated compared with those in parental cells. Reducing hyper-O-GlcNAcylation by OGT knockdown (KD) markedly facilitated chemosensitivity to the corresponding chemotherapeutics in both cells, and combination treatment with OGT-KD showed more severe growth defects in chemoresistant sublines. We subsequently verified the suppressive effects of OGT-KD monotherapy on cell migration/invasion in vitro and xenograft tumor growth in vivo in chemoresistant UCB cells. Transcriptome analysis of these cells revealed 97 upregulated genes, which were enriched in multiple oncogenic pathways. Our final choice of suspected OGT glycosylation substrate was VCAN, S1PR3, PDGFRB, and PRKCG, the knockdown of which induced cell growth defects. These findings demonstrate the vital role of dysregulated OGT activity and hyper-O-GlcNAcylation in modulating treatment failure and tumor aggression in chemoresistant UCB.

Survival Outcomes Associated with First and Second-Line Palliative Systemic Therapies in Patients with Metastatic Bladder Cancer

Background: Real-world data on palliative systemic therapies (PST) in treating metastatic bladder cancer (mBC) is limited. This study investigates current trends in treating mBC with first- (1L) and second-line (2L) chemotherapy (CT) and immunotherapy (IT). Methods: A chart review was conducted on patients diagnosed with stage II-IV bladder cancer in 2014–2016. Survival outcomes were compared between chemotherapy, immunotherapy, and supportive care. Results: out of 297 patients, 77% were male. 44% had stage IV disease at diagnosis. Median age at metastasis was 73 years. 40% of patients received 1L PST and 34% received 2L PST. Median overall survival (mOS) was longer in those receiving PST versus no treatment (p < 0.001). Patients receiving CT and IT sequentially had the longest mOS (18.99 months). First-line IT and CT mOS from treatment start dates were 5.03 and 9.13 months, respectively (p = 0.81). Gemcitabine with cisplatin (8.88 months) or carboplatin (9.13 months) were the most utilized 1L chemotherapy regimens (p = 0.85). 2L IT and CT mOS from treatment start dates were 6.72 and 3.78 months, respectively (p = 0.15). Conclusion: real-world mOS of >1.5 years in mBC is unprecedented and supports using multiple lines of PST. Furthermore, immunotherapy may be a comparable alternative to chemotherapy in both 1L and 2L settings.