Stem vaccine against cancer: bad science and loud PR
Oncological fantasy
Vaccination against cancer with stem cells is pointless and unsafeAda Gorbacheva, Independent Newspaper
No matter what they say, no matter what they write about the successes in the treatment of oncological diseases (and in recent years a lot has really been achieved), but God forbid anyone to hear the diagnosis of "cancer".
It is clear with what joy any news of a cardinal victory over cancer, anyone, meets. I really want to believe that such a magic remedy has been found.
Even now, news agencies enthusiastically repeated the Daily Telegraph's message that world science has come close to creating a vaccine against cancer. The newspaper referred to the latest joint work of American and Chinese scientists from the University of Connecticut. The studies were conducted using genetically modified stem cells, on the basis of which the vaccine was obtained. Experiments have shown that these cells have the ability to activate those protective mechanisms that block the development of cancer cells. In mice that were vaccinated, the division of cancer cells was slowed down many times.
The head of the study, Professor Qihai Li, noted that cancer and stem cells have a number of common properties and features from a molecular point of view. He believes that this research has laid the foundations for obtaining a new generation of vaccines that can be used for vaccinations against cancer.
Dmitry Kazansky, Doctor of Biological Sciences, head of the Laboratory of the mechanism of regulation of Immunity at the Blokhin Cancer Center Research Institute of Carcinogenesis, reacted with great skepticism to the publication in the Daily Telegraph. "It follows from the text of the publication that Chinese researchers, by inoculating mice with human cells, gained immunity against a mouse line of rectal cancer cells," Dmitry Kazansky explained in an interview with an NG correspondent. "They explain the effect by immunization with oncophetal antigens similar in human stem and mouse cancer cells."
But there are many other antigens by which these cells can differ, the expert stressed. What exactly the immune response is in this system is a very vague and difficult to interpret matter. For example, an antibody (humoral) response can go to a virus that accidentally infected both cell lines, or to mycoplasma – the eternal enemy of experimenters.
"The experimental system is too complicated to get clear answers," Dmitry Kazansky stressed. – Therefore, apparently, the article did not get into a professional oncology journal. The authors, about whom the Daily Telegraph writes, got the effect by immunizing animals with embryonic stem cells, which you can't get from an adult. The effect of polypotent stem cells was the worst. This means that either animal embryonic stem cells or another person will have to be used to vaccinate people (autologous vaccination turns out to be impossible), which creates the same problems of uncontrolled responses to xenoantigens and to transplant antigens. In addition, there is a risk of introducing some oncogenic virus to a person, as was the case with immunization with live polio vaccines that were grown on macaque cells."
Another remark of Dmitry Kazansky – American researchers have received immunity against subsequent transplantation of tumor cells. The creation of protective immunity against cancer is a hopeless task due to the multiplicity of sources of origin and the "appearance" of malignant cells. Anti-cancer vaccines are used to treat sick people, and universal immunization of the population with cocktails of embryonic stem cells in the hope of preventing cancer is hardly a good idea.
Embryonic stem cells have been repeatedly tried to be used in the experiment for the treatment of neurological and other disorders. To do this, they resorted to transplantation of genetically identical embryonic stem cells. That is, the immune response to them did not develop (although they could be a source of oncophetal antigens). The usual result was the appearance of teratomas – tumors containing various tissues "out of place", as well as hair, nails and teeth.
According to Dmitry Kazansky, the article by Chinese authors from Connecticut is similar to advertising material in order to obtain funding for further research. Another thing is vaccinations against infectious oncogenic viruses (hepatitis B, human papillomavirus): they do significantly prevent the development of liver cancer and cervical cancers.
Portal "Eternal youth" http://vechnayamolodost.ru20.10.2009