Tuesday, June 12, 2012
Singapore - S'pore scientists discover cells that cause HPV-related cervical cancers
SINGAPORE: Scientists in Singapore have discovered a set of cells in the womb that causes human papillomaviruses or HPV-related cervical cancers.
Cervical cancer is the seventh most common female cancer in Singapore and about 200 cases are diagnosed every year.
Infection with HPV is the most common cause or risk factor for cervical cancer.
HPV infection causes a pre-invasive cancer, known as Cervical Intraepithelial Neoplasia, which are pre-cancerous lesions that can progress and potentially become invasive cancer if left untreated.
The team of scientists, from research agency A*STAR's Institute of Medical Biology and Genome Institute of Singapore, worked with clinicians from Boston's Brigham and Women's Hospital (BWH) in this study.
They found that a set of cells, located at the cervix, have unique biomarkers that are seen in all forms of invasive cervical cancers linked to HPV. This means that the signature markers of these particular group of cells can provide a way of distinguishing potentially dangerous pre-cancerous lesions from benign ones.
Their research was published in the prestigious journal, Proceedings of the National Academy of Sciences this week.
The team also showed that these cells do not regenerate when excised. It said these findings have immense clinical implications in the diagnosis, prevention and treatment of cervical cancer.
For example, it raises the distinct possibility that removing this set of cells in young women could reduce their risk of cervical cancer.
Dr Christopher P. Crum, Director of Women's and Perinatal Pathology in the Department of pathology at BWH, said: "It has been a decades-old mystery why cervical cancers caused by HPV arise only from a discrete region of the cervix, known as the 'squamocolumnar junction', despite the presence of the virus throughout the genital tract.
"The discovery of these cells finally resolves this mystery and will have wide-ranging impact, from developing more meaningful animal models of early cervical carcinogenesis to clinical implications."
Dr Wa Xian, Principal Investigator at IMB, said: "Our study also revealed that this exotic population of cells does not reappear after ablation by cone biopsy.
"This finding helps to explain the low rate of new HPV infections in the cervix after excisional therapy and also raises the distinct possibility that pre-emptive removal of these cells in young women could reduce their risk of cervical cancer. This could be an alternative to current vaccines which only protect against HPV types 16 and 18."
Added Dr Frank Mckeon, Senior Group Leader at GIS: "Our previous work on esophageal cancer opened up the possibility of 'preventive therapy' to stamp out the disease by eliminating this small group of cells. This recent work in the cervix further validates this concept and raises important possibilities for early intervention to prevent malignancies linked to very small populations of these unusual, discrete population of cells."
In a landmark paper published in Cell in June 2011, Dr Wa and Dr Mckeon identified a novel mechanism for the evolution of highly aggressive cancers in collaboration with BWH and NUS.
They discovered that a discrete population of cells at the junction of the esophagus and stomach were linked to precursors of esophageal cancer (Barrett's metaplasia).
It was the first time scientists realised that some cancers originate from just a small set of cells that are unique from the other cells that reside around them.