The work by Beloueche-Babari et al offers several insights into the potential role of exploiting tumor PTPS normalization as a non-invasive biomarker of anticancer drug effect in general, and specifically, potential use of these methods in melanoma patients for assessing response to Hsp90 inhibitors, as well as other agents like MEK inhibitors that target associated pathways [18, 19]. Here, PTS is linked to melanoma.