The dermis, the skin's next layer, is a thick layer of fibrous and elastic tissue (made mostly of collagen, with a small but important component of elastin) that gives the skin its flexibility and strength. The dermis contains nerve endings, sweat glands and oil (sebaceous) glands, hair follicles, and blood vessels.
âAll cancers are caused by genetic mutations, and in some cases we know the processes driving them, for example, tobacco smoking in lung cancer, however, our understanding of the causes of mutation in most cancers is remarkably limited,â Grimmond says.
All cancers are caused by mutations in the DNA of cancer cells which are acquired during a person's lifetime. The studies, of a malignant melanoma and a lung cancer, reveal for the first time essentially all the mutations in the genomes of two cancers. Lung cancer causes around one million deaths worldwide each year: almost all are associated with smoking.