OBJECTIVES:
Primary
* Determine the level of p-Chk1 and phospho-histone 2AX (p-H2AX), an indicator of DNA damage, and possibly downstream pathway markers in hair follicles from skin biopsies of patients treated with gemcitabine hydrochloride or irinotecan hydrochloride for advanced solid tumors.
Secondary
* Characterize the method for measurement (immunohistochemistry).
* Measure inter- and intra-patient variability for the biomarker.
* Partially characterize the dynamic time course of p-Chk1 and p-H2AX after administration of a DNA-damaging agent.
OUTLINE: This is a multicenter study.
Patients undergo collection of 2 skin biopsies with hair follicles at 4 and 8 hours or at 4 and 6 hours after the start of irinotecan hydrochloride or gemcitabine hydrochloride treatment on day 1 of course 1. Repeat biopsies will be taken at 4, 6, or 8 hours after the start of irinotecan hydrochloride or gemcitabine hydrochloride on day 1 of 2 successive courses.
Tissue is examined by immunohistochemistry and possibly other methods for changes in p-Chk1 and pH2AX.
PROJECTED ACCRUAL: A total of 60 patients will be accrued for this study.
