title: Interaction of interferon gamma and CPT-11, a new derivative of camptothecin, in human endometrial carcinoma cell lines.
abstract: The anti-proliferative effects of interferon gamma (IFN-gamma) and CPT-11, a new derivative of camptothecin, both singly and in combination, on two human endometrial carcinoma cell lines, HHUA and ISHIKAWA, were examined in vitro. The HHUA cells were responsive dose-dependently to IFN-gamma, while the ISHIKAWA cells were unresponsive to IFN-gamma. Both cell lines were responsive dose-dependently to CPT-11. In both cell lines, IFN-gamma at clinically achievable concentrations (10 and 100 U ml-1 enhanced the anti-proliferative activity of CPT-11 in the range of concentrations where CPT-11 showed more than 10% cell growth inhibition. Sequential treatment with CPT-11 followed by incubation with IFN-gamma resulted in significant cell growth inhibition, but not vice versa. Flow cytometric studies indicated that the combined anti-proliferative effect did not correlate with cytokinetic alterations. Treatment with IFN-gamma did not change the extractable topoisomerase I activity of the HHUA and ISHIKAWA cells. The combination therapy of IFN-gamma and CPT-11 could provide a new approach against endometrial cancer.
authors.affiliation: Department of Obstetrics and Gynecology, Gifu University School of Medicine, Gifu, Japan.
authors.forename: H.
authors.initials: H
authors.lastname: Mori
authors.forename: M.
authors.initials: M
authors.lastname: Sawairi
authors.forename: K.
authors.initials: K
authors.lastname: Niwa
authors.forename: N.
authors.initials: N
authors.lastname: Itoh
authors.forename: T.
authors.initials: T
authors.lastname: Hanabayashi
authors.forename: H.
authors.initials: H
authors.lastname: Kondoh
authors.forename: T.
authors.initials: T
authors.lastname: Tamaya