Establishment and Characterization of a Highly Metastatic Ovarian Cancer Cell Line

Abstract

Ovarian cancer leads the worst prognosis among all types of gynecologic malignancies, and patients are often diagnosed at an advanced stage. Ovarian cancer also has a high rate of metastasis; however, the detailed mechanisms for ovarian cancer prone to metastasis remain unclear. In this study, we used continuous in vitro screening of the human ovarian cancer A2780 cell line to establish a cell line (A2780-M) which shows high invasiveness and motility. Compared to the parental cells, A2780-M cells express elevated protein levels of CD44, CD133, CD34, and β-catenin. A2780-M cells are also more resistant to chemotherapeutic agents SN-38 and Docetaxel. Thus, the A2780-M cell line is a new ovarian metastatic cancer cell line that expresses tumor stem cell surface markers and adhesion-related membrane proteins and is with higher motility and invasiveness.

Figure 1

Characterization of A2780-M and A2780 cells. (a) Morphological characteristics of A2780 and A2780-M cells. The A2780 cells are shown to be polygonal or oval in shape (top), and A2780-M cells are more fusiform and fibrous in appearance (bottom); (b) graph shows the different growth rate of A2780-M and A2780 cells.

Figure 2

Wound Healing assay representative images showing the difference of cell motility of A2780 (top) and A2780-M cells (bottom) determined with gap refilling analysis.

Figure 3

Transwell assay. (a) Graph shows the results of cell motility for A780-M and A2780 cells determined by EISEN real-time marker-free cell function analyzer; (b) representative images showing the results of invaded cells in transwell incubation chambers.

Figure 4

Drug resistance for A2780 and A2780-M. Graphs show the dose responses of A2780-M and A2780 cells to the treatments of DDP (top left), SN-38 (top right), DTX (bottom left), and THP (bottom right). Data represents the average results from at least three independent experiments. Error bars indicate standard deviation.

Figure 5

β-Catenin expression in A2780 and A2780-M cell lines. (a) Representative images of IHC showing the β-catenin expressions; (b) Western blotting results showing the expression of β-catenin protein.

Figure 6

Tumorigenicity analysis. (a) Graph showing the change of body weights for nude mice transplanted with xenografts established from A2780-M and A2780 cells; (b) graph showing the growth rates of xenograft tumors; (c) representative image showing visible lung metastatic nodules in lung organ observed in nude mice bearing A2780-M-xenograft 40 days after tumor cell inoculation; (d) nude mice inoculated with parental A2780 cells showed no metastases in lung organ. Data represents the average results from at least three independent experiments. Error bars indicate standard deviation.