The biological effects of UV rays, due to their interaction with organic molecules, are responsible for phenomena such as tanning, freckles, sun rashes; they are also the main cause of skin cancer. Any living organism would be seriously damaged by the UV rays coming from the Sun if a good part of the radiation were not filtered by the Earth's atmosphere.
A low wavelength of ultraviolet rays, below 121 nm, ionizes the air so quickly that it is almost completely absorbed before it reaches the ground. On the other hand, ultraviolet is also responsible for strengthening bones, participating in the formation of vitamin D, in most terrestrial vertebrates, so UV has both beneficial and harmful effects on human health.
UV can also induce excitation of the DNA molecule, a state of excitation that can last a more or less long time, and normally the return to the ground state occurs without any alterations being induced; however, episodically, improper chemical bonds can be produced between adjacent pyrimidines, damage not always effectively repaired by biomolecular mechanisms.
UV-A is considered less harmful than other bands, but can always cause high-dose burns and a syndrome called Majorcan acne. They are considered responsible for skin cancers such as melanoma, basal cell carcinoma or non-melanocytic tumors, in a similar way to the more energetic and harmful UV-B.
The study: Ultraviolet Radiation and Basal Cell Carcinoma: An Environmental Perspective, published on the Frontiers in public health, explained: "Ultraviolet radiation (UVR) is a known carcinogen participated for the development of skin cancers.
Solar UVR exposure, particularly ultraviolet B ( UVB), is the mostly significant environmental risk factor for the occurrence and progress of basal cell carcinoma (BCC). Both cumulative and intermittent high-grade UVR exposure could promote the uncontrolled replication of skin cells.
There are also exsiting other contributing environmental factors that combine with the UVR exposure to promote the development of BCC. DNA damage in formation of skin cancers is considered to be a result of UVR toxicity. It is UVR that could activate a series of oncogenes simultaneously inactivating tumor suppressor genes and aberrant proliferation and survival of Furthermore, mounting evidence demonstrates that inflammatory responses of immune cells in the tumor microenvironment plays crucial role in the skin tumorigenesis as well.
In this chapter, we will follow the function of UVR in the onset and development of BCC. We describe the factors that influence BCC induced by UVR, and also review the recent advances of pathogenesis of BCC induced by UVR from the genetic and inflammatory aspects."