09 June 2012
IN LABOUR, MOM MAY PASS ON CANCER VIRUS TO BABY
Is the virus responsible for cervical cancer in women causing eye cancer in their children? A study by Chennai doctors may soon have some answers.
The department of biotechnology has given Rs 3.5 crore to Vision Research Centre of Sankara Nethralaya to study if human papillomavirus (HPV) that causes cervical cancer in women is responsible for retinoblastoma, a cancer of the retina found in children below the age of six. Many of the tumours in the eyes of such children were found to have the virus. Researchers suspect that the virus may be pushed into thechild from the mother during delivery, something which has been proven in the case of HIV.
Sankara Nethralaya will work with experts from Institute of Bioinformatics, Bangalore, and Johns Hopkins University in the US on the project that may help doctors prevent and treat retinoblastoma in children better. About 1,500 cases of retinoblastoma are reported every year in the country, mostly in children in the 1-2 age group. Many cases are treatable, but 60% are detected late, forcing surgeons to remove the eye to save the child.
It is believed that retinoblastoma is caused by a genetic mutation, but more than half the cases don’t have a family history of eye cancer. Hence, HPV becomes a suspect. Dr Sangeetha B Desai, author of the study published in medical journal Pediatric Blood Cancer last month, says the findings strengthen the hypothesis that HPV plays a role in development of retinoblastoma.
"We want to know why we are seeing HPV in eye tumours,"said Sankara Nethralaya deputy director (research) S Krishnakumar, who will head the retinoblastoma project. Studies by Sankara Nethralaya in 2009 had also showed the presence of HPV in eye tumour samples. HPV 16 was detected in 12 out of 21 tumours. They found that children younger than 18 months were significantly associated with the presence of HPV DNA, compared to children above 24 months.
That gives enough reason for scientists to suspect that the virus is pushed to the baby from the mother when the uterus contracts during labour. "While passing through the cervix, the baby has chances of picking up the virus from the uterine fluids. The virus may later cause mutations that lead to uncontrolled cell division," Dr Krishnakumar said. Oncologist Dr Vikas Ketan hopes that such fundamental research will help find important answers. "In most cases, we try to save the eye. But it becomes impossible in many cases. We hope a new treatment helps," he said.
BUG FROM THE WOMB
Sankara Nethralaya will work with experts from B’lore’s Institute of Bioinformatics & the US’s John Hopkins univ to help docs prevent retinoblastoma in children
CERVICAL CANCER | Cervical cancer occurs when abnormal cells on the cervix, lower part of the uterus, grow out of control. It is the most common cancer found among Indian women
CAUSED BY | Human papilloma virus (HPV). Not all types of HPV cause cervical cancer. The most common subtypes in the country are HPV 16 and 18 (in pic) TRANSMITTED THROUGH | Sexual contact
RETINOBLASTOMA CATCHING THEM YOUNG | It is a rare type of eye cancer that usually develops in the retina before the age of six AFFECTS THE EYE | In most children, the disease affects only one eye. However, one out of three children with retinoblastoma develops the cancer in both eyes At least 1,500 children develop retinoblastoma in India every year 60% of cases are detected late, forcing surgeons to remove the eye to save the child LINK BETWEEN THE TWO
There are increasing instances of scientists finding HPV in retinoblastoma tumours. Like in HIV, scientists suspect that a mother may pass on the virus to the baby when she is in labour
This year, doctors at the Tata Memorial Hospital in Mumbai found that HPV was present in 53 out of 76 (69.7%) retinoblastoma tumours. The study lent support to the hypothesis that infection of HPV–16/–18 may play an important role in the development of retinoblastoma in children