The prognostic value of co-expression of two CSCs biomarkers, CD44 and CD133, with wild-type EGFR (wtEGFR) and EGFRvIII in CRC patients, was studied and CD133/CD44 expression was associated with primary resistance to irinotecan and acquired resistance to anti-EGFR inhibitors in vitro. The gene discussed is EGFR; the disease is colorectal carcinoma.