Monitoring Antitumor Efficacy of Rapamycin in Kaposi Sarcoma

Overactivation of basal P70S6K in PBMCs from renal transplant recipients appears to be associated with the presence of Kaposi sarcoma dermal lesions; conversely, kinase inhibition is linked to regression of skin cancer lesions. Thus, monitoring P70S6K phosphorylation can help predict and monitor the biological effectiveness of rapamycin in renal transplant recipients with Kaposi sarcoma and possibly adjust the biologically active doses of the mTOR inhibitor.