Expression of CYP and GST in human normal and colon tumor tissues.

We investigated the immunohistochemical staining characteristics of cytochrome P450 1A1 (CYP1A1), CYPB1, CYP2E1, and glutathione S-transferase P1 (GSTP1), GSTT1, GSTO1, GSTK1 in colon tumor and surrounding normal colon tissues. Tissues were obtained from 47 patients with colon adenocarcinoma and the staining intensity of tumor and control tissues was compared. CYP1A1, CYP1B1, CYP2E1, GSTP1, GSTT1, GSTO1 and GSTK1 expressions in colon cancer cells were significantly greater than those in normal colon epithelial cells. No significant relation was found between the isoenzyme expressions and age, gender, smoking status, tumor grade and tumor stage. The higher expressions of CYP1A1, CYP1B1, CYP2E1, GSTP1, GSTO1, GSTT1 and GSTK1 in tumor than in normal colon tissues may be important for colon cancer progression and development.

Does maternal exposure to artificial food coloring additives increase oxidative stress in the skin of rats?

Glutathione-S-transferase (GST) and cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) metabolize and detoxify carcinogens, drugs, environmental pollutants, and reactive oxygen species. Changes of GST expression in tissues and gene mutations have been reported in association with many neoplastic skin diseases and dermatoses. Widely used artificial food coloring additives (AFCAs) also reported to effect primarily behavioral and cognitive function and cause neoplastic diseases and several inflammatory skin diseases. We aimed to identify the changes in expression of GSTs, CYP1A1, and vascular endothelial growth factor (VEGF) in rat skin which were maternally exposed AFCAs. A rat model was designed to evaluate the effects of maternal exposure of AFCAs on skin in rats. "No observable adverse effect levels" of commonly used AFCAs as a mixture were given to female rats before and during gestation. Immunohistochemical expression of GSTs, CYP1A1, and VEGF was evaluated in their offspring. CYP1A1, glutathione S-transferase pi (GSTP), glutathione S-transferase alpha (GSTA), glutathione S-transferase mu (GSTM), glutathione S-transferase theta (GSTT), and VEGF were expressed by epidermal keratinocytes, dermal fibroblasts, sebaceous glands, hair follicle, and subcutaneous striated muscle in the normal skin. CYP1A1, GSTA, and GSTT were expressed at all microanatomical sites of skin in varying degrees. The expressions of CYP1A1, GSTA, GSTT, and VEGF were decreased significantly, while GSTM expression on sebaceous gland and hair follicle was increased. Maternal exposure of AFCAs apparently effects expression of the CYP1A1, GSTs, and VEGF in the skin. This prominent change of expressions might play role in neoplastic and nonneoplastic skin diseases.