Stromal cell

In cell biology, stromal cells are connective tissue cells of any organ, for example in the uterine mucosa (endometrium), prostate, bone marrow, and the ovary. They are cells that support the function of the parenchymal cells of that organ. Fibroblasts, immune cells, pericytes, endothelial cells, and inflammatory cells are the most common types of stromal cells.

The interaction between stromal cells and tumor cells is known to play a major role in cancer growth and progression.

Stromal cells (in the dermis layer) adjacent to the epidermis (the very top layer of the skin) release growth factors that promote cell division. This keeps the epidermis regenerating from the bottom while the top layer of cells on the epidermis are constantly being "sloughed" off of the body. Certain types of skin cancers (basal cell carcinomas) cannot spread throughout the body because the cancer cells require nearby stromal cells to continue their division. The loss of these stromal growth factors when the cancer moves throughout the body prevents the cancer from invading other organs.