skin tumours

Question 1

main differences between naevi and melanoma

Answer 1

• naevi is a benign neoplasm of melanocytes

- melanoma has the capacity to invade surrounding tissue and naevi does not

Question 2

why is UVB a complete carcinogen

Answer 2

because UVB at a high enough dose has the ability to cause tumorigenesis by itself

Question 3

what types of genes are important in tumorigenesis

Answer 3

• tumour suppressor gene e.g. p53
• proto-oncogene e.g. HGFR
• DNA repair genes e.g. p53
• genes involved in apoptosis e.g. p53

Question 4

what mutations are commonly seen in the p53 gene mutated in sun-exposed skin

Answer 4

C –> T

CC –> TT

Question 5

give two examples of why hypoxia in the cancer microenvironment is problematic for treatment

Answer 5

radiotherapy requires the presence of oxygen to produce ROS, which damage cancer cells

chemotherapy requires the presence of dividing cells, viable hypoxic cells are slow growing due to reduce oxygen levels

Question 6

what are the 3 aims of medical nutrition therapy

Answer 6

• minimize weight loss
• prevent / correct nutritional deficiencies
• manage complications that impair food intake

Question 7

how does epigenetics play a role in cancer development

Answer 7

epigenetic modifications are involved in regulating gene expression at the level of gene transcription. epigenetic modification can effectively ‘turn off’ important genes involved with tumour suppression or they can ‘turn on’ genes involved with normal cell growth e.g. proto-oncogenes