in east China, announced his findings on human gestation which will be of great value in anti-cancer research.
Zhang's research and achievements have created wide interest here and abroad. He and his colleagues have spent years carrying out cancer research employing biological and genetic engineering methods.
Zhang said a human embryo, formed by the combination of a sperm and an ovum, evolves to be a 3000 to 3500 kg baby within the short period of no more than nine months. Complete genetic information is released and inherited during this evolutionary period.
According to Zhang, research into fetal evolution has proved that cancer genes are active at the same level in an embryo as are other normal genes promoting development of common cells.
It is amazing that an embryo can allow normal cells to grow at a very fast pace, while automatically checking the growth of cancer genes.
This fact confirms the existence of anti-cancer factors, which can differentiate cancer cells from normal cells and also curtail cancer cell development.
Zhang said that each of 100,000 factors in an embryo is a genetic valve key to solve corresponding diseases. In the embryonic stage, all genetic valves are open and unblocked with valve keys to keep them functional.
These keys are lost one by one as a person matures. The problem could be resolved by finding the keys which weed out specific diseases in the embryonic stage, according to Zhang.
Cancer cells are groups of out-of-order cellular variants which expand themselves at a rapid rate, yet at a still slower rate than that of embryonic development.
This suggests that a highly efficient management system is at work in the embryonic development stage which arranges the orderly growth of cells. Unfortunately the way the system works is not yet understood by modern science and becomes dormant when a baby is born,
If the system was reactivated and lost keys were got back, human beings could regain the ability to control cellular variation, namely, by controlling cancer cell development and changing them into cells which do nor harm the human body, the professor says.
If this happens, the treatment of cancer or tumors will be simplified and doctors will be happy to abandon traditional measures like chemotherapy which leads to massive destruction of normal cells and tissues, and sharp degeneration of the human immune system.
Zhang and his team are working hard to find the elusive factors through molecular biology and biochemistry.
He was the first in China to use silkworms as bioreactors to develop biologically active factor products by using silkworm embryos as material.
In addition, Zhang also developed biologically active protein by using embryos of chickens and testing it on rats and macaques. The test results show a way of increasing the number of white blood-cells, prolonging life and lifting life standards of the test animals
Zhang's theory and supposition of anti-cancer factors are certificated with the success of cultivating biologically active substances by using embryos of silkworms and chickens.
To finalize his theory, Zhang and his fellows are using embryos of animals like sheep as bioreactors to develop genetic therapeutics for the cure of cancer.
(People's Daily October 21, 2001)
