Gene Expression

At the DNA level, a cancerous cell is usually characterized by:

At least one active oncogene and the mutation of several tumor-suppressor genes

Abnormalities in gene expression can lead to ___________

Cancer

Why is cancer more prevalent in older people?

Cancer involves an accumulation of mutations, and older people have had more time to accumulate mutations in their DNA

Oncogenes:

Cancer-causing Ex: Proto-oncogenes

Most human cancers are:

Caused by the accumulation of somatic mutations

Gene expression in bacteria is regulated primarily by:

Controlling the transcription of genes into mRNA

Chromatin is composed of both:

DNA and Histone Proteins

A cancer cell:

Does not respond to the chemical signals that control cell division

Tumor-Suppressor Gene

Help prevent uncontrolled cell growth

In what way can cancer be hereditary?

One or two of several mutations necessary for full cancer development can be inherited, giving a person a predisposition to developing cancer

Proto-oncogenes

Responsible for normal cell division and growth

In the human genome, oncogenes:

Stimulate cell division

Differential Gene Expression

The expression of different genes by cells with the same genome Causes differences between cell types

BRCA1 and BRCA2

Tumor-Suppressor genes

p53 gene

Tumor-suppressor gene

What two genes are often mutated in colon cancer?

ras and p53