A potential link between lung cancer and human papilloma virus may make parents even more glad about vaccinating their children with Gardasil®. Not only are the children protected against viruses that commonly cause cervical cancer, they may be protected against some forms of lung cancer as well.
The April 25th version of Nature News reports (1) that two viruses, HPV (Human papilloma virus) and measles virus, have been found in lung tumors.
From Nature News:
Samuel Ariad of the Soroka Medical Center in Beer Sheva, Israel, and his colleagues began by analyzing tumours taken from 65 lung cancer patients. They found evidence of measles virus proteins in about half of their samples.
The work provides the first hint that the measles virus may contribute to lung cancer, and follows on Ariad's previous studies showing a possible association between the measles virus and a cancer of the lymph tissue called Hodgkin's disease3.
In addition, Arash Rezazadeh of the University of Louisville in Kentucky and his colleagues tested 23 lung cancer tumours for HPVs. In five cases, the samples tested positive for the virus's DNA. Others have previously shown a possible link between the virus and lung cancer, but, as in this case, have relied on small sample sizes.
It's not known if the viruses caused the tumors; however, many kinds of cancer are associated with viral infections and HPV, at least, is a well-established cause of both cervical cancer and warts. The connection between measles virus and cancer isn't as clear, but there is one recent study that shows a link between measles virus and Hodgkins disease.
From Nature News:
As much as 20% of the world's cancers have been linked to infections. In addition to the connection between HPVs and cervical cancer, chronic infections by hepatitis-B and -C viruses contribute to liver cancer, and the bacterium Helicobacter pylori has been associated with stomach cancer.
In February, researchers reported viral genome sequences found in an aggressive form of skin cancer called Merkel cell carcinoma, although it remains to be seen precisely how the virus contributes to skin cancer, if at all. And some have proposed that a virus similar to the 'mouse mammary tumor virus' -- which causes breast cancer in mice -- could also be associated with breast cancer in humans.
Our ability to uncover hidden viruses is improving greatly due to Next Generation DNA sequencing technologies (2). It is likely that further research will find viruses involved in many more health problems.
In this case, more research is needed to prove a link between these viruses and lung cancer. If these early results are confirmed, many of us will doubly glad that we had our children vaccinated against HPV.
NOTE: I should add that lung cancer can be caused by multiple things - smoking, asbestos, maybe measles?, - a vaccine against HPV would only protect against lung cancer if that cancer was caused by the same strain HPV used in the vaccine.
1. Heidi Ledford "Viruses found in lung tumours" Nature News, April 25, 2008.
2. Feng, H. , Shuda, M. , Chang, Y. & Moore, P. S. "Clonal Integration of a Polyomavirus in Human Merkel Cell Carcinoma" Science 319, 1096-1100 (2008).
Possible but unlikely IMO. Haven't seen the data so don't know what kind of study design this was (or wasn't) or whether they looked for the virus in non-neoplastic cells in the same patients or in non lung CA patients. So those are some obvious open science type questions. But research also takes place in a social and political environment and some kinds of work gains currency for reasons other than science. I am not saying this isn't an a researchable question, only making an observation.
For those old enough to remember the big cancer and virus hype of the late 60s and early 70s will also remember that it found especially fertile ground at a time when there was a lot of interest in carcinogens in the environment. This was a nice political solution to the problem: blame the patient, not the patient's environment and immunize them against your tobacco smoke consensate. The they can smoke as much as they want (until their heart and lungs give out, that is).
I agree, Revere, these are preliminary data and shouldn't give anyone the notion that smoking is safe.
But I don't think it's correct to characterize the link between viruses and some kinds of cancer as "hype." I remember when the notion of a virus causing cervical cancer was widely disputed, too. We know now that there are multiple causes for cancer - some cancers are related to our own genes, some are caused by viruses, maybe even multiple kinds of viruses. It will be awhile before we understand the relative contributions from the different mechanisms.
This is going to be the end of civilization. Now, teenage girls who get this vaccine will think it is OK to have sex AND smoke cigarettes!
sandy: Mostly I was talking about the late 60s, early 70s where the evidence was extremely poor but the money was going to viruses (an investment that didn't pay off). Today there is good evidence for some viruses being either causative or co-factors, most notably HBV (liver) and HPV, but possibly others as well, But the epidemiological evidence for most cancers is slim while the evidence for environmental and occupational factors is pretty strong. Maybe because I'm an environmental epidemiologist I'm not objective about this, but I blog mostly about viruses so I'm cognizant of their importance. Anyway, it was just an observation from someone with a long memory (and the gray hairs to go with it).
I do appreciate your perspective. I first learned about the link between viruses and cancer when I was an undergraduate student in the early 80's and I raised tadpoles with kidney tumors. Those frog tumors were caused by Herpes Lueke Tumor Virus, but I also became fascinated with retroviruses like Rous Sarcoma Virus (causes cancer in chickens) and oncogenes. Perhaps my thinking is warped a bit by history, too.
Joseph: Sigh, it's hard to be a parent. Don't tell my daughters, okay?
There is new hope for parents. A Swedish experimental vaccine against smoking has just entered phase II trials:
I scanned the Nature News piece but couldn't find strain info. Are they the same ones that are associated with cervical cancer (or, if this bears fruit, are we looking at a new HPV vaccine)?
You should submit this post to the Cancer Research Blog Carnival here: http://blogcarnival.com/bc/cprof_2479.html
I'll check the link when I'm back in town.
its a good thing to know that there is already a vaccine agains lung cancer.
ATG: It's not clear that there's a vaccine yet. So far, this is still a wishful possibility.