Question

1) if i were a histopathologist, what are two characteristics i would look for in a biopsy for possible cancerous tissue??

2) why might the structure of a genome be messed up in cancers?

3) miRNAs were logical extensions of the proto oncogenes/tumor suppressor gene framework because:

a) miRNAs are small

b) miRNAs regulate mRNA translation

c) miRNAs are key receptors of cell signals

Answer 1

1) The size and shape of cancerous cells are quite abnormal and hence they can be either smaller in size or larger than non-cancerous cells. Therefore, looking for the size is quite significant.

The size of the nucleus of a cancerous cell is often larger and darker which is another feature for detecting cancerous cell in the biopsy.

2) There are several changes in the pattern of the DNA methylation in a cancerous cell. There is a close link between DNA methylation, histone proteins modifications, and chromatin structure. Hence, this process affects the formation of heterochromatin and euchromatin which is not the case with a typical process occurring inside a normal cell and ultimately the genome of a cancerous cell becomes messed up.