Senescence & Cancer

[2810712]

Replacing a specefic gene appears more difficult than inducing another gene that will oppose the action of that specefic gene eg. kill the cancer cell or inhibit cell div.s or stop the expression of that specefic gene etc. ; but how can we introduce some gene only in the cancer cells ? I think, the recognition of cancer cells , for this we must introduce some changes in the vector being used........

What Do U Think?

hrushikesh

[mith]

I'm probably making this sound easier than it is but I have the notion that the viruses would invade almost all the cells. If the cell is normal nothing is changed since the old DNA is the same as the new one inserted. The abnormal cells though would change for the better.

[2810712]

Yes,good IDa , U can add another copy
but how will you REPLACE the gene ?

hrushikesh.

[mith]

Well viruses generallly attack a host cell by replacing its internal machinery with virii dna. If the virii DNA was one inserted by us(beneficial) then we could do what I've said above.

[DevGrp]

The trick would be indentifying the gene to change. This could be different in different people. The other problem is that the viral method would only work for ressesive mutations as the original "mutated" copy of the gene would still be present.

I'm don't sure how many cancer mutations are resesive but I suspect not many as we are a diploid species.

One way round this might be to use RNAi to silence the mutatated gene that was causing the rampant cell cyling. You still have the problem of targetting your viral vector just to cancer cells.

On the other hand gene therapy is being used in cancer research

(couldn't find an interesting FREE review)

[mith]

Isn't there a way to do it like with weed killers? I know weedkillers only target fast growing weeds and will leave your lawn grasses alone. Is it possible to apply the same principle to our cells?

[DevGrp]

Possibly, you need to target a feature of a cancer cell which it possesses but normal cells don't. A lot of work has been done on antibodies which recognise some feature of cancer cells, but not normal cells. these antibodies can then be used to deliver drugs / toxins direct to the cancer cells.

We did some work on a toxin which effected mitochondria, particularly highly active ones. The idea was that rapidly dividing cells (cancer cells) might be particularly sensitive. The toxin sure killed cells in culture but the idea went no further.

[2810712]

We did some work on a toxin which effected mitochondria, particularly highly active ones. The idea was that rapidly dividing cells (cancer cells) might be particularly sensitive. The toxin sure killed cells in culture but the idea went no further.

What about muscles and other such cells having more mitochondria ?
What if you can toxify only cancercells using appeopriate Abs?

hrushikesh

[DevGrp]

Yes we were looking at some sort of targetting.

Interestingly tumours tend to have more leaky blood vessels than normal tissues so sometimes drugs accumulate more in tumours naturally.

[2810712]

leaky! I didn't know . I knew that they have more blood vessels. What makes them leaky? This means there is some difference in the angiogenesis by tumours, isn't it?

hrushikesh

[DevGrp]

my understanding, is that the process of angeogeneis in tumours is a bit shoddy and the blood vessels aren't as intact / well built as normal blood vessels.

A quick google search found:


http://www-ermm.cbcu.cam.ac.uk/04008270h.htm

[2810712]

Thax for the link.


If U don't mind , in exactly which field U are doing research,DevGrp ?
thanx

hrushikesh