BACKGROUND: Chemotaxis is defined as directional cell movement of cells towards 
concentration gradients of solubilized attractants, whereas chemokinesis is 
defined as random cell movement in the absence of chemoattractant gradients. 
Since tumor cell motility plays an important role in the process of tumor 
invasion and metastasis, we investigated these two distinct motile behaviors in 
highly invasive tumor, malignant mesothelioma.
MATERIALS AND METHODS: Chemotaxis and chemokinesis of mesothelioma cells were 
assayed using Boyden chambers fitted with filters coated with collagen type IV 
and different growth factors and cytokines were used as chemoattractants.
RESULTS: We found that growth factors such as epidermal growth factor, 
transforming growth factor-alpha, amphiregulin, heparin-binding epidermal growth 
factor-like growth factor, beta-cellulin, insulin-like growth factor-I, 
insulin-like growth factor-II and stem cell factor stimulated directional 
(chemotactic) and/or random (chemokinetic) motility in all mesothelioma cell 
lines tested, whereas none of acidic fibroblast growth factor, basic fibroblast 
growth factor, granulocyte-macrophage colony-stimulating factor or interleukin-6 
induced migration in the same mesothelioma cells.
CONCLUSION: These findings provide evidence that: (i) multiple growth factors 
can induce chemotaxis and chemokinesis in malignant mesothelioma cell lines, and 
(ii) may contribute to our understanding of the highly invasive behavior of 
malignant mesotheliomas in vivo.