The aim of this study was to determine the effects of oxidative stress caused by low dose 5-ALA and its methyl ester mediated PDT to IGF-2, the IGF-2 receptor (IGF-2R) and IGF2-BP-1 expression in the SW620 colon cancer cell line, additionally combined with the evaluation of apoptosis after PDT, including immunohistochemical studies on BAX protein. The gene discussed is IGF2; the disease is colonic neoplasm.