In a rare case, that has baffled medical scientists around the world, cancer cells passed over from a mother to her unborn baby.
The discovery was made by scientists in when an 11-month old baby developed cancer soon after her mother died from leukemia.
The 28 year-old Japanese mother had developed lymphoma during the course of her pregnancy. A team of scientists from the Institute of Cancer Research , found that leukemia cells had crossed the placenta and spread from the infected mother to the fetus, defying age-old biology theories.
Though, for over 100 years, scientists had established the possibility of such transmission, this case provides hard evidence of the phenomena, Nik Zeps, the scientific adviser to Cancer Council Australia told the Guardian. However, he added that it is a rare occurrence for pregnant women to contract cancer and even rarer for the unborn to get infected with it.
In this case, the mother was detected with advanced leukemia a month after she delivered the baby girl and died. 11 months later, the baby was hospitalized for swollen right cheeks, and eventually was diagnosed with tumor in her jaw, by which time the cancer had spread to her lungs.
It is fascinating to note how the cells escaped the baby's immune system, which should have recognized them as foreign invaders and destroyed them, if they had attempted to cross the placental barrier.
Researchers found the cancer cells of mother and baby carried the identical mutated cancer gene, called BCR-ABL1, but the infant had not inherited this gene. This meant that the cells must have come from the mother. The scientists tried to figure out if there was any scope of immunological acceptance of the cells by the fetus.
On further examining the genes of the cancer cells in the infant's and they found a deletion mutation that means some of the DNA was missing. This was an important discovery as the missing cells were responsible for making the distinction between the mother's ce''s and the baby's cells.
This explained why the baby's immune system did not react to the cancer cells, and hence did not make any effort to counter them.