He is also an internationally recognized leader in the study of both cancer metastasis and growth factors that regulate cell behavior, as well as a professor at the Weill Cornell Graduate School of Medical Sciences.

[citation needed] He completed a postdoctoral fellowship in 1982 in the laboratory of Michael P. Czech, PhD, at Brown University, where he determined the composition of the receptor for the hormone insulin.

[9] In 2003, Dr. Massagué and colleagues documented the effects of the gain or loss of the TGF-β pathway in a mouse model of breast cancer, showing that it can increase lung metastases but suppress the growth of primary tumors.

[10] That same year, he published another paper that found that two genes expressed in breast cancer were increased in the presence of TGF-β and enabled the tumor cells to metastasize to the bone.

[17] On January 13, 2020, a study by Massagué-led Sloan Kettering Institute in New York published a report in Nature Cancer, which deciphered the origin of metastases, which were previously believed to have begun by genetic mutations.