Ingersoll, Susan Blaydes, Ahmad, Sarfraz, Stoltzfus, Gregory P., Patel, Sheylan, Radi, Michael J., Finkler, Neil J., Edwards, John R., Holloway, Robert W.
funding text
This research study is funded by the Bankhead-Coley Cancer Research Program (State of Florida Department of Health) and partial support from the Ovarian Cancer Alliance of Florida and the Gala Endowed Program for Oncologic Research.
abstract
Objectives: The objective of this study was to functionally characterize a fluorescent highly tumorigenic ovarian cancer line to test cellular therapy in combination with cytokines or chemotherapies in experimental models. Methods: A fluorescent highly tumorigenic subline (SKOV3-AF2) was derived from the SKOV3 ovarian cancer cell line. Peripheral blood mononuclear cell (PBMC)-mediated cytotoxicity of SKOV3-AF2 in the presence of interleukin 2 (IL-2) and interferon alpha-2b (IFN alpha-2b) was assayed by lactate dehydrogenase release. Sensitivity of SKOV3-AF2 cells to polyethylene glycol-IFN alpha-2b and IL-2 was assayed in a xenograph nude mouse model. Histopathology was performed to determine necrosis and tumor-infiltrating lymphocytes in the solid tumors. Reverse transcriptase-polymerase chain reaction was used for gene expression analyses of E-cadherin and cysteine-rich 61 (CCN1). Results: The SKOV3-AF2 subline exhibits increased cytotoxicity (up to 70%), mediated by PBMCs, IL-2, and IFN alpha-2b, compared with parental SKOV3-red fluorescent protein (RFP) cells. SKOV3-AF2 cells are more tumorigenic in vivo as indicated by tumor incidence, time to sacrifice, tumor weight, and ascitic fluid production. SKOV3-AF2 tumor growth was inhibited by polyethylene glycol-IFN alpha-2b but not low-dose IL-2. Histopathology revealed that the tumors consisted of poorly differentiated surface epithelial carcinoma. SKOV3-RFP, and -AF2 cell lines as well as -AF2 tumors expressed E-cadherin. SKOV3-AF2 derived tumors expressed CCN1; however, the SKOV3-RFP and SKOV3-AF2 cell lines did not. Conclusions: Characterization of SKOV3-AF2 cells revealed that it is more susceptible to PBMC-mediated cytotoxicity than SKOV3-RFP and highly tumorigenic in a xenograph model, and AF-2 tumors express genes that promote aggressive behavior. Collectively, our data suggest that the SKOV3-AF2 subline will be a useful tool to test cellular therapy for the treatment of ovarian cancer utilizing experimental models.