In addition to causing regression of the Mullerian duct in the male embryo, Mullerian Inhibiting Substance (MIS) inhibits the growth of epithelial ovarian cancer cells, which are known to be of Mullerian origin. Because the uterine cervix is derived from the same Mullerian duct precursor as the epithelium of the ovary, we tested the hypothesis that cervical cancer cells might also respond to MIS. A number of cervical cancer cell lines express the MIS type II receptor, and MIS inhibits the growth of both human papilloma virus-transformed and non-human papilloma virus-transformed cervical cell lines, with a more dramatic effect seen in the latter. As in the ovarian cancer cell line OVCAR8, suppression of growth of the C33A cervical cancer cell line by MIS is associated with induction of the p16 tumor suppressor protein. However, in contrast to OVCAR8 cells, induction of p130 and p107 appears to play an important role in the inhibition of growth of C33A cells by MIS. Finally, normal cervical tissue expresses the MIS type II receptor in vivo, supporting the idea that MIS could be a targeted therapy for cervical cancer.M ullerian Inhibiting Substance (MIS), also known as antiMullerian hormone, has long been known for its canonical activity of causing the regression of the embryonic Mullerian duct, the anlagen of the fallopian tubes, the surface epithelium of the ovaries, the uterus, the cervix, and the upper third of the vagina. Given the sensitivity of these tissues to MIS, we proposed that this 140-kDa hormone could inhibit the growth of Mullerian ductderived tumors and demonstrated that partially purified preparations of bovine MIS inhibited growth of an ovarian cancer cell line (1, 2) and of primary ovarian and endometrial cells in vitro (3, 4). Using more highly purified recombinant human MIS, we demonstrated growth inhibition of both human ovarian cancer cell lines and primary tumors in vitro and in vivo (5-8). Recently, we showed that the epithelial ovarian cancer cell line OVCAR8 expresses the MIS type II receptor and responds to MIS by growth inhibition mediated through a retinoblastoma protein (pRB)-independent mechanism involving the up-regulation of p16 (6). As a member of the INK4 family of cyclin-dependent kinase (CDK) inhibitors, p16 regulates the cell cycle by inhibiting the kinase activity of cyclin͞ CDK (CDK 4͞6) complexes (9), and induction of p16 is known to disrupt cell cycle progression and to regulate apoptosis (10-14).To study whether other Mullerian duct-derived tumors might be sensitive to MIS, we investigated its effect on human cervical cancer cell lines. The third most common neoplasm of the female genital tract, cervical cancer accounts for Ϸ10% of all cancers in women and resulted in 4,800 deaths in 1999 in the United States (15). A significant proportion of these cancers are due to infection with high risk subtypes of the human papilloma virus (HPV) (16). Despite a significant reduction in the annual cervical cancer death rate in the United States since the introduction of the Papanico...