Dr.
Michael Har-Noy of Immunovative Therapies, an Israeli biotech company founded
in 2004, says that the idea that cancer occurs because of weakened immunity is
erroneous and misguided.
Dr.
Michael Har-Noy explains that when a normal cell grows into a cancer cell,
changes in the display of surface antigens give rise to tumor-associated
antigens (TAAs) that could be detected by one’s immune system. In 1909,Ehrlich first theorized that a person’s own immunity protected them
from cancer, an idea that was promoted in the 1950s by Lewis Thomas and later
by Sir Macfarlane Burnet, who theorized that a patient’s immune cells had a
“surveillance” system that identified and killed precancerous and cancerous
cells. Dr. Michael Har-Noy indicates
that this hypothesis was based on the idea that cancer cells continually form
in a person’s body and that their immune system must identify and kill cells
that express surface TAAs
This
hypothesis goes on to state that in instances where the patient’s immunity is
compromised, the surveillance system is then disabled, and the cancer cells grow
unchecked and clinical disease occurs. Dr. Michael Har-Noy says that
this is the idea behind the notion that in cancer, the patient’s immune system
is weakened, and that it must be reinforced to effectively attack the cancer
cells.
Dr.
Michael Har-Noy goes on to indicate that there is much evidence contradicting
this theory. While a minority of the more unusual cancers develop in immune
compromised patients, most malignant tumors arise in individuals with intact
immunity. Also, many tumors, especially
epithelial cell cancers, have a significant number of inflammatory cells. This
includes an array of leukocyte infiltrates consisting of neutrophils, macrophages,
mast cells, eosinophils, often in the presence of lymphocytes. Dr. Michael
Har-Noy points out that malignant tumors are usually profusely infiltrated with
immune cells, which contradicts the hypothesis of deficient immune recognition of
TAAs.
Additionally,
many previous efforts to augment the immune response resulted in faster growth
rather than slower growth of the cancer. For example, in mice, a newly formed
cancer of combined mesenchymal and epithelial origin grows more quickly of it
stimulates a response from the patient’s immune cells. Dr. Michael Har-Noy indicates that cancers
that stimulate a significant immune response will often, if left undisturbed,
grow more quickly than those that do not trigger the patient’s immunity. So, the notion that cancers are “invisible” to
the patient’s immune cells and that the patient’s immune response needs to be
enhanced appears to be wrong.
Dr.
Michael Har-Noy concludes
that the issue may be that the patient’s immune reaction to the cancer is the
incorrect type of response. Therefore,
by attempting to augment an immune response that has already failed to protect the
patient against malignancies, tumor propagation may be sped up rather than
slowed. This is likely the reason that
most immune cancer therapies to date have been ineffective.
Source: http://www.immunovative.co.il
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