Doxorubicin-induced alopecia is associated with sebaceous gland degeneration

Alopecia, accompanied by skin dryness, is one of the distressing side effects often occurring in chemotherapy-treated cancer patients. Little is known of the effects of chemotherapy on sebaceous glands, despite their importance in hair follicle homeostasis. This study investigates sebaceous gland morphology and the response of SZ95 sebaceous gland cell line to doxorubicin (DXR) treatment. The morphology of sebaceous glands during intraperitoneal DXR treatment was investigated by optical and electron microscopy in a 7-day-old rat model and further confirmed in an adult mouse model. Moreover, in vitro studies using the SZ95 sebaceous gland cell line were performed to assess the response of sebocytes to DXR in terms of cell proliferation, apoptosis, and necrosis. DXR treatment induced sebaceous gland regression and occasionally caused their complete disappearance. This observed damage and disappearance preceded DXR-induced hair loss. In vitro experiments using the SZ95 sebaceous gland cell line indicated that DXR treatment induced a differentiation process leading to premature sebocytes apoptosis. Owing to the importance of the sebaceous gland in hair follicle homeostasis, DXR-induced involution of this gland might be related to subsequent hair loss.