The role of ABC transporters in ovarian cancer progression and chemoresistance

• Increased expression of ABC transporters is one cause of chemoresistance.
• This review summarises the roles of all 48 ABC transporters in ovarian cancer.
• Current list of chemotherapy drugs transported by ABC transporters.
• Summary of ABC transporter inhibitors and studies/trials assessing therapeutic benefit.
• A better understanding of their function will lead to more effective therapies.

Over 80% of ovarian cancer patients develop chemoresistance which results in a lethal course of the disease. A well-established cause of chemoresistance involves the family of ATP-binding cassette transporters, or ABC transporters that transport a wide range of substrates including metabolic products, nutrients, lipids, and drugs across extra- and intra-cellular membranes. Expressions of various ABC transporters, shown to reduce the intracellular accumulation of chemotherapy drugs, are increased following chemotherapy and impact on ovarian cancer survival. Although clinical trials to date using ABC transporter inhibitors have been disappointing, ABC transporter inhibition remains an attractive potential adjuvant to chemotherapy. A greater understanding of their physiological functions and role in ovarian cancer chemoresistance will be important for the development of more effective targeted therapies. This article will review the role of the ABC transporter family in ovarian cancer progression and chemoresistance as well as the clinical attempts used to date to reverse chemoresistance.