Potential Biomarker of Response to Vismodegib in Basal Cell Carcinoma
Posted: Friday, March 20, 2020
Although localized cases of basal cell carcinoma are usually responsive to surgery, advanced localized and metastatic cases generally require alternative interventions. According to an Israeli study published in Scientific Reports, baseline levels of the gene GAS1 may prove to be a possible marker for response to the hedgehog pathway inhibitor vismodegib in patients with advanced localized basal cell carcinoma. The study was conducted by Amir Sternfeld, MD, of Tel Aviv University, and colleagues.
Biopsies were taken from 12 patients with advanced localized basal cell carcinoma both before and after treatment with vismodegib; samples from 22 patients with localized cancer were also taken. Expression of 40 genes in the hedgehog signaling pathway were analyzed.
Three genes in the hedgehog pathway—GAS1, GLIS2, and PRKACG—were more highly expressed in patients with advanced localized than in those with localized cancer (P < .05). There was an increase in expression of 16 genes (P < .05) after treatment in the cohort with advanced localized disease. Of the 12 patients, 4 had a complete response to vismodegib, 6 had a partial response, and 1 had no response. (One patient who received a partial dose of the drug was thus excluded from analysis.) The patients who had a complete response tended to have a lower expression of GAS1 than did those who had a partial response (mean = 1874.83 ± 905.26 vs. 3901 ± 420.05; P = .014).
The study investigators suggested that this study may lay the groundwork for future research on the role of the GAS1 gene in resistance to biologic treatments. “GAS1 might also serve as a target for future treatments,” they proposed.
Disclosure: The study authors reported no conflicts of interest.