Basal-cell carcinoma
Basal-cell cancer is a very common skin cancer. It is much more common in fair-skinned individuals with a family history of basal-cell cancer and increases in incidence closer to the equator or at higher altitude. There are approximately 800,000 new cases yearly in the United States alone. Up to 30% of Caucasians develop basal-cell carcinomas in their lifetime. In Canada, the most common skin cancer is basal-cell carcinoma (as much as one third of all cancer diagnoses), affecting 1 in 7 individuals over a lifetime.
P19 cell
Cancer cells in humans may result in the patient's death if the aggressive cancer cell grows and metastasizes. However, researchers utilize these cells to study the development of cancer cells in order to find more specific treatments. For developmental biologists, embryonal carcinoma, which is derived from teratocarcinoma, is a good object for developmental study. In 1982, McBurney and Rogers transplanted a 7.5 day mouse embryo into the testis to induce tumor growth. Cell cultures containing undifferentiatied stem cells were isolated from the primary tumor which have a euploid karyotype. These stem cells were named embryonal carcinoma P19 cells. These derived P19 cells grew rapidly without feeder cells and were easy to maintain. Moreover, the multipotency of P19 cells was then confirmed by injecting the cells into blastocysts of another mouse strain. The researchers found that there were tissues from all three germ layers growing in the recipient mouse. Based on their continuous studies, they further derived subtype cell lines from original P19 cells: P19S18, P19D3, P19RAC65 and P19C16. The difference between these subtype cell lines is the ability to differentiate into neuronal cells or muscle cells in response to treatment with retinoic acid or DMSO, respectively.
More recently, various studies generate cell lines that were initially derived from differentiated P19 cells. Due to the pluripotency of P19 cells, those new derived cell lines can be ectoderm, mesoderm and endoderm-like cells.