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.Which of the following types of malignancies would be least amenable to retroviral based gene therapy ?
A. Malignant melanoma
B. Ovarian cancer
C. Renal cell cancer
D. Chronic myelogenous leukemia
E. Primary brain cancer
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It is E ?. Only brain cells are not dividing, therefore retrovirus would not infect normal brain cells, other than tumor. All other tissues are epithelial cells which are capable dividing, and are susceptible to retrovirus infection, resulting in side effect or toxicity. I am not sure if this is the right answer.
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primary brain cancer is not caused by neurons, but it is caused most often by astrocytes.
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Is it D ?
Gene therapy with retrovirus is Gene replacement therapy, which the purpose is to replace missing geneproduct in a cell.
All other except D has some nature of Tumor suppressor gene knocked out.
CML has t(9.22) and it is kinda gain-od-function mutation.
Therefore , I think we need Gene-Blocking therapy with CML using Antisense therapy or Ribozyme therapy.
Correct me if I am wrong .
All I wrote is from Kaplan Genetics Lecture note
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It is D.
First, retrovirus only infect proliferating cells (not quiescent cells). All the cancer cells are supposed to be proliferative.
Second, CML is a hematopoietic stem cell diease (bcr-abl fusion happens at stem cell level), although bcr-abl blcoks differentiation and apoptosisof myeloid cells. Stem cell population is resistant to retrovirus infection because they are usually quiescent.
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ANS is the D. well explained by sage and dathvader.
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hi hellohie
in kapaln genetic page 351 (2004) under the topic of remaining challenges ,they mentioned that brain may be difficult to reach with most exisiting vectors!!!!!!!!!!!!!