Compositions and methods of treating cancer using compositions comprising an inhibitor or endothelin receptor activity

One-third of all individuals in the United States alone will develop cancer. Although the five year survival rate has risen dramatically nearly fifty percent as a result of progress in early diagnosis and therapy, cancer still remains second only to cardiac disease as a cause of death in the United States. Twenty percent of Americans die from cancer, half due to lung, breast, and colon-rectal cancer. Moreover, skin cancer remains a health hazard. Described herein are results which show that an endothelin receptor antagonist, BQ788, increases pigmentation and significantly reduces the viability of 7 human melanoma cell lines in culture. Moreover, it is described herein that administration of BQ788 significantly slows melanoma tumor growth in nude mice, including a complete growth arrest in half of the mice treated systemically. Thus, inhibitors of endothelin receptor activity are described herein as beneficial for the treatment of cancer.