How myosin organization of the actin cytoskeleton contributes to the cancer phenotype.

The human genome contains 39 genes that encode myosin heavy chains, classified on the basis of their sequence similarity into 12 classes. Most cells express at least 12 different genes, from at least 8 different classes, which are typically composed of several class 1 genes, at least one class 2 gene and classes 5, 6, 9, 10, 18 and 19. Although the different myosin isoforms all have specific and non-overlapping roles in the cell, in combination they all contribute to the organization of the actin cytoskeleton, and the shape and phenotype of the cell. Over (or under) expression of these different myosin isoforms can have strong effects on actin organization, cell shape and contribute to the cancer phenotype as discussed in this review.