Abstract 4489: Effect of cancer-associated fibroblasts on the progression of malignant melanoma cells

Abstract

Abstract Introduction Malignant solid tumor is composed of not only cancer cells but also various types of stromal cells, which include fibroblasts, vascular endothelial cells, and immune cells. Currently, it has been reported that fibroblasts in tumor stroma, namely cancer-associated fibroblasts (CAFs), might affect cancer progression. Some studies suggested that CAFs have the stimulation-activity of the malignant potential of melanoma cells, but some reports mentioned their inhibitory-activity of melanoma cells. In this study, we investigated the effects of CAFs on the proliferation and invasion ability of malignant melanoma cells. Material and Method We used 2 malignant melanoma cell lines, MMAc and COLO679. Three CAFs were established from sebaceous carcinoma or skin malignant melanoma. Serum-free conditioned medium (CAF-CM) from CAF was prepared as follows. CAF were seeded into 100 mm plastic dishes with 10 ml of DMEM containing 2% FCS. To obtain CAF-CM, CAF were washed by PBS and then incubated for 3 days with serum-free DMEM. The conditioned medium was collected as CAF-CM. Serum-free DMEM was used as the control. CAFs were used before the 15th passage in culture. The effect of CAF-CM on the proliferation of the melanoma cells was determined by cytometry assay using Coulter Counter. The effect of CAF-CM on the motility of the melanoma cells was examined by Matrigel-invasion assay. Result CAF-CM significantly increased the proliferation of melanoma cell, in compared the control. Under the condition of adding 25% of CAF-CM, the number of MMAc cells were increased about 300% after 72 hours of incubation, and 105% after 120 hours of incubation that of COLO679 increased about 56% after 72 hours of incubation, 130% after 120 hours of incubation. CAF-CM significantly increased the invasion of MMAc cells. The invasion of MMAc cells were increased about 200% after 72 hours of incubation following the addiction of 25% CAF-CM. In contrast, CAF-CM did not affect on the invasion of COLO679 cells. Conclusion CAFs are associated with the proliferation and invasion of malignant melanoma cells. Citation Format: Heishiro Fujikawa, Masakazu Yashiro, Takaharu Hatano, Shusaku Maeda, Hisashi Motomura. Effect of cancer-associated fibroblasts on the progression of malignant melanoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4489.