The recently approved drug vemurafenib (Zelboraf) has been hailed as a breakthrough in the treatment of melanoma, the deadliest form of skin cancer. But roughly one-quarter of patients who take the medication develop a troublesome side effect: secondary skin cancers called squamous cell carcinomas.
Now, a new study by researchers at the Jonsson Comprehensive Cancer Center at the University of California, Los Angeles, and colleagues identifies the specific genetic mechanism that causes this side effect.
we found is that vemurafenib blocks the mutation that makes the
melanoma grow, but when patients have skin cells with another mutation
that's probably induced from sun exposure, there the drug has the exact
opposite effect and causes these squamous cell cancers to grow," said
Dr. Antoni Ribas, co-senior author of the study and an associate
professor of hematology/oncology at UCLA... Read More