Question

You are a prominent cancer scientist leading a government laboratory, you just received bottle of colon cancer biopsy along with some normal colon tissue collected from a patient.

(A) Describe and give examples of the traditional ways and modern omics methods you would use in classifying this colon tumor tissue.

(B) After a week, additional clinical testing results of the patient came back, the colonoscopy failed to find any polyps, and your latest lab test result also indicated the MLH1 gene expression was lost in the tumor sample.
1.   Based on these data, which genetic disease would you suggest the patient is suffering from? (1 mark)
2.   Name and describe the cellular process by which of MLH1 is involved; and outcome of losing MLH1 gene expression .
3.   Name and describe the molecular basis of the process by which often involved in driving diminished expression of MLH1 . Describe also molecular mechanism a normal cell would use to counter act the “process” .

(C) Describe in details the advanced laboratory techniques by which you could use to study the “process” occurred to the MLH1 locus.

Answer 1

a .stages . A . Invasion of cancer but not breaching muscularis mucosa.

Stage B . Breaching the muscularis propria but not involving lymph nodes.

Stage C . Lymph nodes involved.

..1 ...This is heridetary non polyposis colorectal cancer (HNPCC) it is characterirised by an increased risk of colorectal cancer and also cancers of endometrium, ovary, stomach, and small intestine.

2.It is an autosomal diminant condition caused by mutation in one of the DNA mismatch repair genes. There is microsatellite instability.

3. Tumour supressor genes apply brakes to cell proliferation . Abnormalities in TSG,s leads to colon and endometrial carcinoma.

The most commonly affeected are MLH1 , MSH2 . mean age is 45 years .most cancers develop in 45 years. And in proximal colon. Females have 30 to 50 percent lifetime risk of developing endometrial cancer.

C Tests . DNA sequencing.

Cancer genome sequencing.

Histolgic and cytolgic smears.

Immunohistochemistry

Flow cytometry.