Mesenchymal cells and

When cells express proteins that are not expected, the phenomenon has been described as aberrant expression. In many cases the expression has been shown to be true expression by molecular analysis, such as the staining of cytokeratin in some mesenchymal cells and then-corresponding tumors such as leiomyosarcoma, rhabdomyosarcoma, and angiosarcoma. 

Most neoplasms are classified and named based on (1) the cell or tissue of origin and (2) benign or malignant growth characteristics. There are two basic cell types from which neoplasms may originate mesenchymal cells and epithelial cells (Figure 2). Mesenchymal pertains to mesenchyma (embryonic... 

Cytokeratin Subclasses Expressed Aberrantly In Mesenchymal Cells and Tumors... 

Morris-Wiman, J. and Brinkley, L.L. (1990) Changes in mesenchymal cell and hyaluronate distribution correlate with in vivo elevation of the mouse mesencephalic neural folds. Armt. Rec. 226 383-395. 

Newgreen, D.F. (1990) Control of the directional migration of mesenchyme cells and neurites. Semin. Dev. Biol. 1 301-311. 

Jiang, T-X., Jung, H-S., Widelitz, R.B., Chuong, C-M. (1999). Self-organization of periodic patterns by dissociated feather mesenchymal cells and the regulation of size, number and spacing of primordial. Development, Vol.126, pp. 4997-5009. 

The ECM refers to the connective tissue that surrounds mesenchymal cells and to the basement membrane (BM) that encompasses parenchymal cells. The ECM contains a large variety of PGs, including members of the aggrecan family, which interact with hyaluronan, and of the decorin family, which have leucine-rich repeats. However, the former are predominantly chondroitin sulfate or keratan sulfate PGs. These PGs can be major tissue constituents, such as aggrecan in cartilage or decorin in tendon. Interestingly, the HSPGs in the ECM are mostly restricted to BMs. 

---