RE: NCRP 136 / Immunology, DNA repair, cancer.../Tumor viruses

["Bjorn Cedervall" <bcradsafers@HOTMAIL.COM>]

>The medical community is finding more evidence that cancers can be

initiated by exposures to viruses.  A good example is cervical cancer.

>From this perspective, the immune system may indeed be important with

respect to whether one "contracts" cancer, though from Bjorn's

discussion, it may not be significant in the body's response (or lack

thereof) to the cancer itself.

---

Thank you Susan,



This example relates to papilloma viruses (excellent reviews are available - 

I read some many years ago). The viruses may bind to proteins involved in 

the initiation of S phase (cell cycle).



This is on the initiation level. I had the later stages in mind - and 

whether the immune system could fight a cancer _once it started_. I 

definitely think that this (prevention level) is a level where the immune 

system may have a function. But this means that the immune system may 

prevent cancer - so that the cancer never is even initiated.



The same is probably true for any virus working with reverse transcriptase - 

making DNA from RNA (retroviruses - the enzyme was first named RNA-dependent 

DNA polymerase) - the key articles appeared in June 1970 in Nature (D. 

Baltimore, R. Dulbecco and H. Temin - Mizutani (spelling?) was also involved 

but didn't get the Nobel Prize.  I remember it well because I gave a talk on 

it in April 1975 - the university teacher was mad at me because I spent 35 

minutes on it rather than 20 minutes (I was a student with too much interest 

in the topic and forgot formalities) - it became the Nobel Prize later the 

same year. The implication was immediately clear - that a virus could be the 

initiator of some types of tumors.



It is getting late in Stockholm - I must sleep - and get up in less than 

five hours from now. I will later try to give meaningful responses to the 

others as well.



Bjorn Cedervall   bcradsafers@hotmail.com





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