Vismodegib

Basal cell carcinoma is the most common skin tumour, with the majority of the cases occurring on the head and neck district, where cosmetic and functional results are crucial. It can be locally destructive if not diagnosed early and treated appropriately. Surgery is the treatment of choice for most le-sions, but aggressive, recurrent, or unresectable tumours can be challenging to manage. Advanced basal cell carci-noma includes high recurrence risk subtypes, in which standard therapies demonstrate lack of efficacy. This led to a need for investigating more deeply the pathogenesis of the disease and to the discovery of the implication of the hedgehog pathway. The development of systemic inhibitors of this pathway provides new treatment options for patients with advanced disease, resulting in survival improvement. Food and Drug Administration, before, and European Medicines Agency later approved 2 Hedgehog pathway inhibitors for the treatment of advanced basal cell carcinomas, vismo-degib and sonidegib. Here, we present a review of the current English language literature trying to analyze differences in the 2 drugs as a head-to-head comparison between them has not already been documented in a randomized controlled clinical trial. Although vismodegib and sonidegib showed similar efficacy and safety profiles, in an indirect comparison scenario, sonidegib has shown slightly better outcomes in locally advanced basal cell carcinoma than vis-modegib. They present different molecular structures, as they bind different residues on their targets and develop resistance for different mutations. In a future scenario, clinical trials comparing the 2 drugs are needed, as well as expanding data on discontinuation of therapy and/or consequential administration of them, with the aim to improve our clinical practise.

Background: In this study we aimed to develop a new in vivo bioluminescence-based tool to monitor and to quantify colon cancer (CC) liver metastasis development. Methods: HCT 116 cells were transducted with pLenti6/V5-DEST-fLuc for constitutive expression of firefly luciferase. Infection was monitored analyzing endogenous bioluminescence using the IVIS Lumina II In vivo Imaging System and a positive clone constitutively expressing luciferase (HCT 116-fLuc) was isolated. HCT 116-fLuc cells were left untreated or treated with 1 μM GDC-0449, a Hedgehog pharmacological inhibitor. Moreover, 1 x 106 HCT 116-fLuc cells were implanted via intra-splenic injection in nude mice. Bioluminescence was analyzed in these mice every 7 days for 5 weeks. After that, mice were sacrificed and bioluminescence was analyzed on explanted livers. Results: We found that in vitro bioluminescence signal was significantly reduced when HCT 116-fLuc cells were treated with GDC-0449. Regarding in vivo data, bioluminescence sources consistent with hepatic anatomical localization were detected after 21 days from HCT 116-fLuc intrasplenic injection and progressively increased until the sacrifice. The presence of liver metastasis was further confirmed by ex-vivo bioluminescence analysis of explanted livers. Conclusions: Our in vitro results suggest that inhibition of Hedgehog pathway may hamper CC cell proliferation and impel for further studies. Regarding in vivo data, we set-up a strategy for liver metastasis visualization, that may allow follow-up and quantification of the entire metastatic process. This cost-effective technique would reduce experimental variability, as well as the number of sacrificed animals.