Is it true that scientists have finally found a safe and effective treatment for brain tumors without the negative side effects that radiation and chemotherapy has?

Authors Avatar

TECHNOLOGY REVIEW

Volume 1 Issue 10                                                                                            March 2001

Gene Therapy for Brain Tumors

Is it true that scientists have finally found a safe and effective treatment for brain tumors without the negative side effects that radiation and chemotherapy has?

A

 fairly recent method has emerged for the treatment of brain tumors—gene therapy.  Gene therapy, when perfected, will give people new genes that will stop a disease or fix an abnormality.

Brain Tumor—

Courtesy of The Whole Brain Atlas

Different type of scan--Courtesy of The Whole Brain Atlas

     It sounds idealistic to insert a desired gene into a human; however, it’s easier said than done.  

Scientists currently are using vectors to deliver genes and there seems to be some progress with this tactic.  Vectors are circular self-replicating DNA (such as a plasmid, which are DNA molecules or a virus, a nonliving agent) in which additional genes are introduced in a test tube or container (Nester 816).  Using these as vectors is a good choice because a plasmid is the part of the DNA that can be transferred to another cell and the function of a virus is to insert its genes into another host cell.  The new genes for the patient are then attached to the vector and are ready for delivery; the new genes are carried into the host cell with the vector and are replicated within the vector (Nester 816).  In short, gene vectors are disabled viruses that carry new genes to the damaged cells and allow for transfer of the new genes (Univ. of Iowa).

A vector can carry the desired gene to the diseased cells, but how can a vector actually help with brain tumors?  

E. Antonio Chiocca tells us that gene vectors have many functions (23):

  1. to kill tumor/diseased cells (the new genes given are either directly toxic to the tumor/diseased cells or encode for products that will become toxic in the presence of a prodrug); these genes are called CYTOTOXIC GENES
Join now!

  1. to suppress the growth of the tumor/diseased cells but not kill the cells; these are called GROWTH SUPPRESSIVE GENES

  1. to replace a deficient, defective, or lacking-gene product; these are called THERAPEUTIC GENES

Scientists have to develop vectors that won’t cause inflammation and immune recognition so that these genes will not actually make the tumor worse (Chiocca 4).  Vectors also have to be targeted as specifically as possible (reach the focal point of the problematic area) and not cause uncontrolled growth.

There are many types of vectors that are currently being tested, including the retrovirus ...

This is a preview of the whole essay