Recent studies have shown the presence of human papillomavirus (HPV) genome in
retinoblastoma (RB)
tumor samples. There is no information on the HPV status in the RB
tumors of Indian patients. We studied the presence of HPV genome in RB
tumor samples from patients with unilateral
tumor. Forty-four fresh RB
tumor samples and 30 non-neoplastic donor retinas were analyzed for the presence of HPV 16 and 18 genome by nested and seminested polymerase chain reaction.
Tumor tissue sections were also used to assess the expression of the
retinoblastoma (
Rb) protein. All 30 control tissues were negative for HPV genome. Among the 44
tumor samples, there were 23
tumors with invasion of optic nerve/choroid and 21
tumors with no invasion. HPV
DNA was present in 21/44 (47%) RB
tumors. Among 21 unilateral RB
tumors that were positive for HPV
DNA, HPV 16 was detected in 12/21 (57%)
tumors. However, HPV 18 was negative in all the
tumors.
Rb protein was absent in 16 (71%) of 21
tumors that had HPV
DNA. However, Rb was also absent in 20 (86%) of 23
tumors that were HPV negative. Children younger than 18 months old were significantly associated with the presence of HPV
DNA compared with children above 24 months old (P<0.014). Our study shows the presence of HPV and HPV 16 in a subset of RB
tumor samples. However, further studies are in progress to know the role played by HPV in RB.