[Establishment of human ovarian carcinoma cell lines with directional highly lymphatic metastasis and study of their biological characteristics]

Abstract

Objective: To establish a human ovarian carcinoma cell line with directional highly lymphatic metastasis and to study their biological characteristics.

Methods: The clone cells of ovarian carcinoma, SKOV3, were inoculated into the hind foot pad of nude mice. The cancer cells of lymph node metastatic foci were transplanted into nude mice again when the metastatic nude of mice were observed. After repetition of this procedure for 3 cycles, the metastatic rate and the metastatic paths were observed in nude mice of every passage. We used limited dilution method to separate and select colonial cells with directional highly lymphatic metastatic potentials from the lymphatic metastasis of human ovarian carcinoma cell line SKOV3. The cells with biological characteristics were assayed by growth curve, HE staining, karyotype analysis, nude mice transplantation and immunohistochemistry, respectively.

Results: We established a series of cell lines from lymph node metastasis and designated them as SKOV3-PM1, SKOV3-PM2 and SKOV3-PM3 cell strain. When the cells of SKOV3-PM3 were injected into the hind foot pad of nude mice, they produced 100% (10/10) spontaneous lymphatic metastasis. The lymphatic metastatic rates (26/10) were stable and higher than the mother cell line (1/10, P < 0.01). The metastatic paths were single, mostly to lymphatic nodes. The proliferation ability was increased in cancer cells of every passage in vivo and in vitro after passage of cancer cells of lymphatic metastatic foci for 3 cycles in nude mice. Cytogenetics study showed the karyotypes of SKOV3-PM3 had modes from 83 to 89, and the SKOV3 from 91 to 105. In comparison of SKOV3 with SKOV3-PM3, the number of chromosomes was significantly different (P < 0.05). Immunocytochemical study demonstrated all cell lines were still polygonal epithelial cells. The expression of epithelial membranes antigen (EMA) was positive, exhibiting features of human carcinoma. The cell of SKOV3-PM3 grew more quickly than SKOV3, their cell population doubling time being 22.7 hours and 49.6 hours, respectively (P < 0.05). Flow cytometry revealed the proportion of cells in DNA synthesis and mitosis was higher in SKOV3-PM1 (24.2%), SKOV3-PM2 (29.4%), and SKOV3-PM3 (36.7%) than in SKOV3 (21.5%; P < 0.05).

Conclusions: The ovarian carcinoma sublines with directional highly lymphatic metastasis potential have been established successfully. The cells could provide a good experimental material for further investigation of the mechanism of metastasis and invasion of ovarian carcinoma.