TM4SF5 and malignant colon neoplasm: Using colon cancer cell lines that minimally express TM4SF1, TM4SF4, and TM4SF5, stable cell lines ectopically expressing the wild-type (WT) proteins or various deletion or chimeric mutants were developed to examine the effects on cellular functions in 2-dimensional (2D; i.e., flat) or 3-dimensional (3D) cultures.