In general, inhibition of Rho and/or ROCK blocked the invasion of the five tumor cell lines tested. The inhibition of Rho and ROCK greatly decreased the invasion level of the rounded morphology cells as it nearly prevented invasion of A375m2 Melanoma and LS174T Colon Carcinoma cells. The inhibition reduced invasion levels of WM266.4 Melanoma cells, which were of mixed morphology. As for elongated morphology cells, the inhibition did little to nothing for prevention of invasion of BE Colon Carcinoma and SW962 Cell Carcinoma cells. This leads to the conclusion that the invasion of rounded morphology cells can be hindered by inhibition of Rho and/or ROCK.

In general, there is no correlation between the depth of cell invasion and the “requirement for Rho and ROCK for cell invasion” (Sahai 713). Five different tumor cell lines were tested for effectiveness of inhibition of Rho and ROCK. Of these five cell lines, two were Melanoma cells (A375m2 (rounded morphology) and WM266.4 (mixed morphology)) and three were Carcinoma cells (BE (elongated morphology), LS174T (rounded morphology), and SW962 (elongated morphology)). Based on the results of this test, it can be concluded that there is no significant information because of the nonexistent correlation between depth of cell invasion and the need for Rho and ROCK.

In general, the combination of the protease inhibitor and the ROCK inhibitor (Y27632), the level of cell invasion is noticeably reduced. The use of the inhibition of ROCK alone on the tumor cells had little effect. The level of invasion of cells slightly decreased when ROCK inhibition was added. However, when the protease inhibitor was added, the level of invasion for each of the cell morphologies increased (level of increase depended on cell morphology). For round morphology (A37m2 Melanoma and LS174T Colon Carcinoma) and mixed morphology (WM266.4 Melanoma) cells, there was a significant increase in the level of invasion; for elongated morphology (BE Colon Carcinoma and SW962 Cell Carcinoma) cells, the increase was slight. From observations, it was also seen that the use of the protease inhibitor alone proved useless for it morphed the elongated morphology cells into round morphology cells thereby increasing the invasion level rather than decreasing it. As a result of this transformation, it was decided that a test involving the combination of ROCK and the protease inhibitor was needed. Results from this test show that the level of invasion decreased greatly for each of the cell morphologies. The transformations of the elongated morphology cells into rounded morphology cells were now blocked by the addition of the ROCK inhibitor. An overall conclusion can be made that the use of Rho, ROCK, and/or the combination of ROCK and protease inhibitor is an effective method in significantly reducing the level of invasion of tumor cells.

Discussion

Methods