Question

u/access/content/group/32962675-55a6-4875-9705-ataca/205002/ 29. David Seligson and his colleagues examined levels of histone protein modification in prostate tumors and their association with clinical outcomes (D. B. Seligson et al. 2005. Nature 435:1262-1266). They used antibodies to stain for acetylation at three different sites and for methylation at two different sites on histone proteins. They found that the degree of histone acetylation and methylation helped predict whether prostate cancer would return within 10 years in the patients who had a prostate tumor removed. Explain how acetylation and methylation might be associated with tumor recurrence in prostate cancer. (Hint: See Chapter 17.)

Answer 1

Histone modifications such as acetylation and methylation play a very important role in gene expression.

Acetylation brings the DNA out of the histone proteins bond and expose them to the transcriptional enzymes to get access for the expression. When an oncogene gets activated by this mechanism, this leads to the development of the tumour.

Methylation brings the repression of genes. Repression of tumour suppressor genes would also lead to the tumour development.