Human retinoblastoma is not caused by known pRb-inactivating human DNA tumor viruses

Human Papillomavirus and Retinoblastoma: Evidence From a Systematic Review and Meta-analysis of Cross-Sectional Studies

Objectives: To study the prevalence and the association of HPV infection in retinoblastoma and to determine the most common genotype presented in RB. Methods: Following the PRIMSA guideline, 14 studies reporting HPV infection in RB acquired from six databases were included. Results: The prevalence of HPV from 941 RB samples was 15.6% [95% confidence interval (CI): 7.3-30]. Mexico followed by India and Brazil had the highest HPV prevalence in RB samples, 61.7% (95% CI: 17-93), 22.5% (95% CI: 9-47), and 12.1% (95% CI: 2-52), in order. HPV 16 was the most common genotype presented in RB samples 23% (95% CI: 9-47), followed by HPV 18 10% (95% CI: 3-30) and the combined HPV 16-18 6% (95% CI: 0-50). We did not find a significant association between HPV and RB [odds ratio (OR): 12.2; 95% CI: 0.65-232; p = 0.09]. However, after removing the largest-weighted study, a significant association between HPV and RB was observed (OR: 45.9; 95% CI; 8.6-245; p < 0.001). Conclusion: HPV prevalence in RB samples was 15% and HPV 16 was the most presented genotype in RB samples. There may be an association between HPV and RB that is needed to be confirmed by high quality future studies. Preventive and treatment measures against HPV infection are essential for the prevention of any possible consequences, in particular, RB.

Human papillomavirus in retinoblastoma: A tertiary eye care center study from South India

Purpose:

This study is aimed to investigate the presence of Human papillomavirus (HPV) DNA in tumors obtained from sporadic retinoblastoma patients.

Methods:

One hundred six tumor tissues obtained from sporadic RB patients were analyzed for HPV infection by use of both seminested PCR and real-time quantitative PCR.

Results:

Of 106 RB patients, 55 were male and 51 were female. The mean age at diagnosis was 26.77 ± 15.36 (mean ± Std. dev) months. Almost all patients presented with leukocoria. Molecular investigation by different methods revealed no HPV positivity in any tumor genome.

Conclusion:

Our study demonstrates no association between HPV and RB, postulating HPV may not be a major risk factor in the etiology of RB.

Molecular evidence of human papillomaviruses in the retinoblastoma tumor

Retinoblastoma tumor (RB) is one of the most prevalent ocular cancers among children. RB may be caused by inherited mutations in RB1 gene as well as some environmental risk factors. Human papillomaviruses (HPV) are suspected as a risk factor of RB due to their pRb inactivating protein. This study evaluated the molecular prevalence of HPV among the RB tumor specimens in Iran. The RB tumor samples were tested for detection of HPV-L1 gene using a nested-PCR approach, and then followed by sequencing and phylogenetic analysis to reveal HPV types. Overall, there were 61 RB tumor samples; 54/61 (88.5%) had unilateral and 7/61 (11.5%) bilateral RB; 55/61 cases (90.2%) had sporadic non-familial RB tumor. HPV-DNA was detected in 6/61 (9.8%) of patients' tumors; the HPV positive RB cases all had unilateral and unfamiliar sporadic RB tumor. HPV type 16 was the most prevalent type identified across the RB tumor samples (3/61, 4.9%). The rate of detected HPV among the RB specimens seems to be considerable. Further investigations are required to elucidate the exact association between HPV and progression to RB.

Human papillomavirus in ocular malignant tumours: a study from a tertiary eye care centre in North India

OBJECTIVE

The present study aims to detect the presence of human papillomavirus (HPV) in ocular malignant tumours, including retinoblastoma, eyelid squamous cell carcinoma (SCC), and sebaceous gland carcinoma (SGC), in the North Indian population.

DESIGN

Prospective observational non randomized study.

PARTICIPANTS

In this study, 142 prospective cases of ocular malignant tumours (retinoblastoma, SGC, and SCC) were included.

METHODS

HPV was detected by multiplex PCR using PGMY09/11 primers in 142 patients with ocular malignancies. This was followed by genotyping using linear array (reverse hybridization).

RESULTS

Of the 142 tumours studied, 72 were retinoblastoma, 30 SGC, and 40 SCC. The HPV genome was detected in 2.8% (4 of 142) of cases by multiplex PCR; all positive cases (4 of 40) were SCC. Genotyping revealed that all positives belonged to the high-risk HPV16 genotype. HPV-positive SCC patients had better disease-free survival. Retinoblastoma and SGC cases were negative for HPV.

CONCLUSIONS

Low prevalence of HPV in ocular malignancies was observed in this study. The HPV genome was detected only in ocular squamous cell carcinoma cases and these patients were associated with better prognosis. HPV may not have a role in retinoblastoma and SGC in the North Indian population.

HPV-16 Detected in One-Fourth Eyes With Retinoblastoma: A Prospective Case-control Study From North India

The incidence of nonfamilial retinoblastoma (RB) is believed to be higher in developing countries. The reports on association of human papillomavirus (HPV) with RB are limited and contradictory. The aim was to investigate the prevalence of HPV in RB tumor tissue. In the prospective study, consecutive eyes enucleated for RB from patients lacking a family history of RB were enrolled as cases over a 3-year period. Controls included donor eyes obtained from the eye bank. Normal retinal tissue from the donor eyes and tumor tissue from eyes with RB was subjected to DNA isolation. Polymerase chain reaction followed by dot-blot hybridization was performed to detect 21 HPV genotypes. The study cohort included 39 RB and 42 normal retinal tissues. A positive result for HPV-polymerase chain reaction was obtained in 10 (25.6%) tumor tissues and none of the control eyes. HPV-16 was the only subtype detected. Socioeconomic status (P=0.58) or maternal age (P=0.58) was not associated with presence of HPV. All HPV-positive patients had undergone a vaginal delivery (P=0.60). HPV-16 was detected in one-fourth cases of nonfamilial RB. None of the control cases (donor eyes) tested positive. Implication of the presence of HPV in RB tissue and role in carcinogenesis needs further elucidation.

Somatic genomic alterations in retinoblastoma beyond RB1 are rare and limited to copy number changes

Retinoblastoma is a rare childhood cancer initiated by RB1 mutation or MYCN amplification, while additional alterations may be required for tumor development. However, the view on single nucleotide variants is very limited. To better understand oncogenesis, we determined the genomic landscape of retinoblastoma. We performed exome sequencing of 71 retinoblastomas and matched blood DNA. Next, we determined the presence of single nucleotide variants, copy number alterations and viruses. Aside from RB1, recurrent gene mutations were very rare. Only a limited fraction of tumors showed BCOR (7/71, 10%) or CREBBP alterations (3/71, 4%). No evidence was found for the presence of viruses. Instead, specific somatic copy number alterations were more common, particularly in patients diagnosed at later age. Recurrent alterations of chromosomal arms often involved less than one copy, also in highly pure tumor samples, suggesting within-tumor heterogeneity. Our results show that retinoblastoma is among the least mutated cancers and signify the extreme sensitivity of the childhood retina for RB1 loss. We hypothesize that retinoblastomas arising later in retinal development benefit more from subclonal secondary alterations and therefore, these alterations are more selected for in these tumors. Targeted therapy based on these subclonal events might be insufficient for complete tumor control.

A case-control study of sporadic retinoblastoma in relation to maternal health conditions and reproductive factors: a report from the Children's Oncology group

Background

The early age at retinoblastoma occurrence, the most common eye malignancy in childhood, suggests that perinatal factors may contribute to its etiology.

Methods

In a large multicenter study of non-familial retinoblastoma, we conducted structured interviews with the parents of 280 cases and 146 controls to elicit information on health during the perinatal period. We used unconditional logistic regression to assess associations between retinoblastoma and parental fertility treatment, birth control use in the year prior to pregnancy, maternal health conditions and the use of prescription medications during pregnancy, and whether mothers breastfed the index child.

Results

Bilateral retinoblastoma was related to maternal underweight (body mass index <18.5) prior to pregnancy [Odds Ratio (OR) = 4.5, 95 % confidence interval (CI) 1.0, 20]. With regards to unilateral retinoblastoma, we observed a negative association with the use of condoms in the year prior to pregnancy (OR = 0.4, CI 0.2, 0.9), and a trend towards a positive association with maternal diabetes (OR = 2.2, CI 0.8, 6.6).

Conclusions

Results from our study suggest a role for several maternal health and reproductive factors. Given that there are few epidemiologic studies of retinoblastoma, our results require replication in studies which utilize medical record review.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1773-0) contains supplementary material, which is available to authorized users.

Update on Ophthalmic Oncology 2013: Retinoblastoma and Uveal Melanoma

PURPOSE

The aim of this study was to discuss the clinical and translational content of the literature as well as advancement in our knowledge pertaining to retinoblastoma and uveal melanoma that were published from January to December 2013.

DESIGN

This study is a literature review.

METHODS

The search terms retinoblastoma and uveal melanoma were used in a MEDLINE literature search. Abstracts were studied, and the most relevant articles were selected for inclusion and further in-depth review.

RESULTS

In retinoblastoma, fewer eyes are lost because of the expanded use of ophthalmic artery chemosurgery and intravitreal melphalan, and the past year marks a deepening in our understanding of these modalities. Knowledge on the genetic underpinnings of uveal melanoma has broadened to include genes associated with a favorable prognosis. This is accompanied by promising results in the treatment of metastatic uveal melanoma.

CONCLUSIONS

This past year, there were important advancements in our knowledge of retinoblastoma and uveal melanoma.

Are human polyomaviruses co-factors for cancers induced by other oncoviruses?

Presently, 12 human polyomaviruses are known: BK polyomavirus (BKPyV), JCPyV, KIPyV, WUPyV, Merkel cell polyomavirus (MCPyV), HPyV6, HPyV7, Trichodysplasia spinulosa-associated polyomavirus, HPyV9, HPyV10, STLPyV and HPyV12. In addition, the non-human primate polyomavirus simian virus 40 (SV40) seems to circulate in the human population. MCPyV was first described in 2008 and is now accepted to be an etiological factor in about 80% of the rare but aggressive skin cancer Merkel cell carcinoma. SV40, BKPyV and JCPyV or part of their genomes can transform cells, including human cells, and induce tumours in animal models. Moreover, DNA and RNA sequences and proteins of these three viruses have been discovered in tumour tissue. Despite these observations, their role in cancer remains controversial. So far, an association between cancer and the other human polyomaviruses is lacking. Because human polyomavirus DNA has been found in a broad spectrum of cell types, simultaneous dwelling with other oncogenic viruses is possible. Co-infecting human polyomaviruses may therefore act as a co-factor in the development of cancer, including those induced by other oncoviruses. Reviewing studies that report co-infection with human polyomaviruses and other tumour viruses in cancer tissue fail to detect a clear link between co-infection and cancer. Directions for future studies to elaborate on a possible auxiliary role of human polyomaviruses in cancer are suggested, and the mechanisms by which human polyomaviruses may synergize with other viruses in oncogenic transformation are discussed.

Spectrum of RB1 mutations identified in 403 retinoblastoma patients

BACKGROUND

Retinoblastoma (RB) is a malignant, childhood tumour of the developing retina that occurs with an estimated frequency of 1 in 20 000. Identification of oncogenic mutations in the RB1 gene aids in the clinical management of families with a heritable predisposition to RB. Here we present the spectrum of genetic and epigenetic changes identified in 194 tumours and 209 blood samples, from 403 unrelated RB patients.

METHODS

Mutation screening was carried out across all 27 RB1 exons and their associated splice sites. Small coding sequence changes were detected using fluorescent conformation analysis followed by sequencing. Large exonic deletions were detected by quantitative fluorescent PCR. Methylation specific PCR of the RB1 promoter was performed to detect epigenetic alterations. Polymorphism analysis was used to determine loss of heterozygosity in tumour samples.

RESULTS

95% of the expected mutations were identified in the tumour samples, with 16 samples exhibiting only one mutation, while two samples had no detectable RB1 mutation. 96% of bilateral/familial RB blood samples and 9.5% of unilateral sporadic blood samples, yielded mutations. 111 were novel mutations.

CONCLUSIONS

The full range of screening techniques is required to achieve a high screening sensitivity in RB patients.

Human papilloma virus in retinoblastoma tissues from Korean patients

Purpose

Recent reports suggest the association of human papilloma virus (HPV) with retinoblastoma. This study was performed to elucidate whether HPV infection is related to retinoblastoma among Koreans.

Methods

A total of 54 cases diagnosed with retinoblastoma were enrolled from Seoul National University Children's Hospital and Seoul Metropolitan Government-Seoul National University Boramae Medical Center. Presence of human papilloma viral DNA was detected by in situ hybridization in formalin-fixed paraffin-embedded retinoblastoma tissues using both probes against high- and low risk HPV types.

Results

The mean age at diagnosis was 22.0 months (range, 1.1 to 98.0 months), and the mean age at enucleation was 27.8 months (range, 1.5 to 112.7 months) among the 54 patients with retinoblastoma. HPV was not detected in any of the retinoblastoma samples using either high risk or low risk HPV probes.

Conclusions

Our study, being the first study in the Korean population, proposes that HPV infection may have no causal relationship with retinoblastoma in Koreans.

Maternal transmission of human papillomavirus in retinoblastoma: A possible route of transfer

Context:

After establishing the presence of human papillomavirus (HPV) in retinoblastoma (RB), the probable role of the mother was investigated.

Materials and Methods:

A total of 21 sporadic RB cases and 15/21 corresponding mothers′ cervical brushings were collected. HPV testing was carried out using multiplex PCR (PGMY09/11 primers) followed by genotyping using line blot assay.

Results:

We found both high- (83%) and intermediate-risk (17%) HPV types in 12/21 (57%) RB samples and only high-risk (100%) types in 6/15 (40%) cervical brushing samples. The single genotype of HPV 16 was found in six cases and HPVs 82, 68 and 35 in one case each. Both HPVs 16 and 59 were found in two cases and HPV 16 and 73 in one case. Three samples of RB harboring HPV 16, HPVs 16 and 59, and HPVs 16 and 73 had HPV genotype 16 in the respective mothers′ cervical brushing samples.

Conclusions:

Maternal transfer of HPV in RB could be a possible route of transmission. However, a larger cohort and sampling of the mothers′ cervical brushings at various stages, i.e. before, during, and after pregnancy will give us insight to propound an alternate mechanism for the development of sporadic RB.

Perinatal characteristics and retinoblastoma

PURPOSE

The etiology of retinoblastoma remains poorly understood. In the present study, we examined associations between perinatal factors and retinoblastoma risk in California children.

METHODS

We identified 609 retinoblastoma cases (420 unilateral, 187 bilateral, and 2 with laterality unknown) from California Cancer Registry records of diagnoses 1988-2007 among children < 6 years of age. We randomly selected 209,051 controls from California birth rolls. The source of most study data was birth certificates. Multivariable logistic regression was used to examine associations between retinoblastoma and perinatal characteristics.

RESULTS

Bilateral retinoblastoma was associated with greater paternal age [for fathers over 35, crude odds ratio (OR) = 1.73, 95 % confidence interval (CI) 1.20, 2.47] and with twin births (OR = 1.93, 95 % CI 0.99, 3.79). Among unilateral cases, we observed an increased risk among children of US-born Hispanic mothers (OR = 1.34, 95 % CI 1.01, 1.77) while a decreased risk was observed for infants born to mothers with less than 9 years of education (OR = 0.70, 95 % CI 0.49, 1.00), a group that consisted primarily of mothers born in Mexico. We observed that maternal infection in pregnancy with any STD (OR = 3.59, 95 % CI 1.58, 8.15) was associated with bilateral retinoblastoma.

CONCLUSIONS

This study supports the findings of previous investigations reporting associations between parental age, HPV infection, and retinoblastoma.

Evidence for the presence of high risk human papillomavirus in retinoblastoma tissue from nonfamilial retinoblastoma in developing countries

BACKGROUND

The prevalence of human papillomavirus (HPV) infection in India is high. HPV infection is known to cause cervical cancer and has also been implicated in the pathogenesis of retinoblastoma (RB), a common intraocular malignant tumor of childhood which can be familial or sporadic. Despite the high incidence of RB in India, its familial form is rare. Hence this study was undertaken to investigate whether high-risk HPV types 16 and 18 are involved in the development of RB.

METHODS

Formalin fixed paraffin embedded RB tissues (n = 76) including prospective cases with corresponding maternal cervical smears (n = 10) were analyzed for the presence of HPV DNA sequences. Expression of the cell cycle regulatory proteins viz; p105, p107, p30, p16, E2F-1, E2F-4, and MiB-1 was studied by immunohistochemistry (IHC) (n = 34).

RESULTS

A total of 53 out of 76 (69.7%) cases were positive for HPV, of these 3 cases were positive for HPV-16, 23 for HPV-18, and 27 for both HPV-16 and -18. Of the prospective cases (n = 10) studied, five cases along with the corresponding maternal cervical cytology smear had identical HPV status. HPV-16 positive tumors were classified as well differentiated (P = 0.013). Nuclear expression of pRB2/p130 showed significant association with HPV-16 infection (P = 0.04) or dual infection of HPV-16/-18 (P = 0.02).

CONCLUSIONS

Our study lends support to the hypothesis that infection of HPV-16/-18 may play an important role in the development of nonfamilial form of RB in children in India.

Retinoblastoma: Recent trends A mini review based on published literature

Retinoblastoma (RB) is the most common intraocular malignancy in children. Recently, there have been significant advances made in the molecular pathology and the management of the disease. Last decade has witnessed better understanding of the genetics of RB, the discovery of new tumor markers expressed by the RB tumors, the identification of high-risk histopathological factors following enucleation, and newer methods of treatment including periocular chemotherapy and superselective intraarterial chemotherapy. All these advances have translated in improved survival rates for the affected children, improved rates of eye salvage, and improved visual outcomes. This article briefly reviews these advances.Method of Literature Search: Literature on the Medline database was searched using the PubMed interface. The search strategy included MeSH and natural language terms using the keywords mentioned. Reference lists in retrieved articles and textbooks were also searched for relevant references.

Molecular pathology of retinoblastoma

Retinoblastoma (RB) is an embryonic neoplasm of retinal origin. For many years, scientists have sought the fundamental origins of tumorigenesis, with the ultimate hope of discovering a cure. Indeed, these efforts have led to a significant understanding that multiple molecular and genetic aberrations, such as uncontrolled proliferation and the inhibition of apoptosis that contribute to the canonical characteristics of tumor biology. Despite these advances, a thorough understanding, such as the precise cells, which are the targets of neoplastic transformation, especially in solid tumors, is currently lacking. The focus of this review is to emphasize the molecular defects involved in the RB tumor progression and mechanisms associated with inhibition of tumor cell apoptotic processes. This review also discusses the importance of target molecules characterization and their potential therapeutic or prognostic use in RB disease.

Low prevalence of HPV in Brazilian children with retinoblastoma

Retinoblastoma is the most frequent intra-ocular malignant tumor of the childhood, occurring in 1 of 18,000-30,000 live births. Little is known about the causes of sporadic retinoblastoma and only a few authors have investigated the etiologic role of human papillomavirus (HPV), with controversial results. Formalin-fixed, paraffin-embedded tissue blocks containing retinoblastoma were retrieved from the archives of the Department of Pathology at Hospital A C Camargo, São Paulo, Brazil. All patients were treated with enucleation (21 children had both eyes enucleated). Retinoblastoma and, when possible, normal retina of each specimen, were micro-dissected under direct light microscopic visualization by using a PixCell II Laser Capture Micro-dissection System. The DNA quality was evaluated by polymerase chain reaction (PCR) amplification of 110 base pairs fragment of the human β-globin gene using primers PCO3+/PCO4+. All globin positive specimens were analyzed by PCR for the presence of HPV DNA using consensus primers GP5+/GP6+. A total of 154 specimens were evaluated. Forty-four patients also had normal retinal specimens available for analysis of DNA HPV. The DNA HPV prevalence among all tumor specimens was 4.6% (95% CI 2.0; 8.8) (7 positive specimens/153 adequate specimens). Among normal retinal specimens, the DNA HPV prevalence was 9.1% (95% CI 2.9; 20.5) (4 positive specimens/44 specimens). There was no statistically significant difference between these rates (P = 0.318). Excluding any experimental failure, our results indicate a low prevalence of HPV DNA in retinoblastomas. We were therefore unable to conclude about the association between these oncogenic viruses and this rare pediatric neoplasm.

Retinoblastoma

Retinoblastoma (Rb) is a malignant tumor that originates from developing retina. Diagnosis based on clinical signs and symptoms and is usually made in children under the age of five years. Mutations in both alleles of the RB1 gene are a prerequisite for this tumor to develop. In most patients with sporadic unilateral Rb, both RB1 gene mutations occur in somatic cells and are not passed over to offspring (nonhereditary Rb). Almost all patients with sporadic bilateral and virtually all patients with familial Rb are heterozygous for RB1 gene mutations that cause predisposition to Rb (hereditary Rb). In families, Rb predisposition is transmitted as an autosomal dominant trait (familial Rb). In addition to Rb, patients with hereditary disease also have an increased risk of tumors outside the eye (second cancer). This risk is enhanced in patients who have received external beam radiotherapy. Analysis of genotype-phenotype associations has shown that the mean number of tumor foci that develop in carriers of mutant RB1 alleles is variable depending on which functions of the normal allele are retained and to what extent. Moreover, phenotypic expression of hereditary retinoblastoma is subject to genetic modification. Identification of the genetic factors that underlie these effects will not only help to arrive at a more precise prognosis but may also point to mechanisms that can be used to reduce the risk of tumor development.

Detection of human papillomavirus DNA in retinoblastoma samples: a preliminary study

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.