photocarcinogenic things Flashcards
what is an oncogene
overactive form of a gene positively regulating cell division eg RAS
what is a proto-oncogene
working normally that can be mutated to an oncogene
what is a tumour suppressor
negatively regulates cell division eg Rb or P53
what are the 6 types of skin
1) always burns never tans, 2) usually burns, can tan, 3) can burn but usually tans, 4) always tans, never burns, 5) brown skin, 6) black skin
what does eumelanin cause colour wise
red
what does pheomelanin cause colour wise
brown and black
what skin cancers are associated with UV
melanoma SCC
what skin cancers are associated with burning
BCC + melanoma
describe UVA damage
indirect damage, causes wrinkles and penetrates deeper than UVB - oxides DNA bases and fixed by bas excision repair (BER)
describe UVB damage
direct damage, causes burning and cancer and is 1000x more damaging than UVA, removed by NER
how do you get UV induced immunosuppresion
depletion of langerhans and reduced inflam and immune response
what is xeroderma pigmentosum
DNA repair syndrome
how does xeroderma pigmentosum present
causes photosensitivity on sun exposed sites (freckles, skin and eye cancer, burns) and neurological degenerations
what gene is defective in xeroderma pigmentosum
nucleotide excision repair genes (NER) (XP A-G)
what is albinism
congenital absence of melanin in eye and retina
