Factors Affecting on the Invasiveness of the Prostate Cancer Cell on In Vitro Model of Basement Membrane

Hyun, Jae Seog; Lee, Hyun; Bahk, Jong Yoon

Abstract

This study was aimed to examine whether biological characteristics of the cancer cell lines have any correlation with distinctive movement of the reconstituted basement membrane in modified Boyden chamber. The in vitro model consists of a chamber and basement membrane filter. Matrigel was applied on the upper surface of the filter and type IV collagen, fibronectin and laminin were also applied to the lower surface of the filter, respectively. The cancer invasiveness was measured by the number of the moved cells through basement membrane differing in component, thickness and incubation time. For chemoattractant study, serum free medium, medium supplemented with 10% fetal bovine serum and medium supplemented with 10% fetal bovine serum and 0.1% bovine serum albumin were used. The invaded cancer cells were counted under high-power field microscope and the morphologic feature of invading cancer cells on reconstituted basement membrane was examined with scanning electron microscopy. The effects of the tissue inhibitor of metalloproteinase-2 (TIMP-2) and wild type tumor necrosis factor-alpha (wTNF-a) on invasiveness of three prostate cancer cell lines (hormone intermediate sensitive ALVA 101, and hormone refractory ALVA 41 and PPC-1) were investigated. The rate of movement of the cancer was reduced increasing thickness of the matrigel but increased in proportion to the incubation time (p<0.05). The components applied on the lower surface of the filter did not affect cancer cell invasiveness (p>0.05). TIMP-2 reduced the invasiveness of three kinds of cancer cell line at both the high and low concentration, indicating that this agent interferes the movement of the cells. Furthermore, this result suggests that TIMP-2 might repress metal-dependent enzymes, which are thought to elicit the invasiveness of the cancer cells. The wTNF-a did not show any effects on the invasiveness of three cell lines. The additive chemoattractant effect of 0.1% bovine serum albumin was not observed and serum free medium also did not induce the cancer cell invasion across the reconstituted basement membrane. The migration of the ALVA 41 and PPC-1 were more than the ALVA 101. The scanning electron microscopic examination showed the figures of migration of cancer cells through the pores on filter, supporting our experiments are performed in validness. The effect of protease inhibitor was distinct in different cancer cell lines studied. From this experiment, we conclude that the rate of movement of both ALVA 41 and PPC-1 cells with shorter doubling time and the hormone refractory was faster than that of ALVA 101 cells with longer doubling time and the hormone sensitive, suggesting biological characteristics of the cells are implicated in degree of cancer cell invasiveness and their malignancies.