Retinoblastoma for Pediatric Ophthalmologists

Survival disadvantage of male children with retinoblastoma in the United States: Surveillance Epidemiology and End Results (2000-2017) Evidence

BACKGROUND

Retinoblastoma is a rare malignancy involving the retina, although, more common among children, with genetic inheritance explaining the incidence as well as acquired forms. The incidence varies among race and sex as well as mortality and survival. The current study aimed to assess retinoblastoma cumulative incidence (CMI), mortality, and survival by sex.

METHODS

A retrospective cohort design was used to assess the CMI, mortality, and survival in this pediatric malignancy based on the Surveillance Epidemiology and End Results (SEER) data 2000-2017. The binomial regression model was used to examine sex differentials in mortality, as well as other study variables, while Cox proportional hazard model was used for the survival variability by sex.

RESULTS

The CMI during this period was higher among males relative to females (males n = 249, 56.7%; females n = 190, 43.3%, χ²  = 2.90, df = 1, p = 0.089). There were sex differences in mortality, with excess mortality observed among males compared to females, risk ratio = 3.40, 95% CI [1.0-15.72]. The survival differences by sex indicated decreased survival among males relative to females, hazard ratio (HR) = 3.39, 95% CI [1.0-15.72]. After controlling for the potential confoundings, namely tumor grade, urbanity, and median income the survival disadvantage of males persisted. Compared to females', males were more than three times as likely to die, adjusted HR = 3.42, 99% CI [0.37-31.60].

CONCLUSION

In a representative sample of pediatric retinoblastoma, there was a sex differential in survival with excess risk of dying identified among males relative to females, which may be explained in part by male X-linkage.

Role of circular RNAs in retinoblastoma

Retinoblastoma (RB), the most common malignant retinal tumor among children under 3 years old, is lethal if left untreated. Early diagnosis, together with timely and effective treatment, is important to improve retinoblastoma-related outcomes. Circular RNAs (circRNAs), a new class of non-coding RNAs with the capacity to regulate cellular activities, have great potential in retinoblastoma diagnosis and treatment. Recent studies have identified circular RNAs that regulate multiple cellular processes involved in retinoblastoma, including cell viability, proliferation, apoptosis, autophagy, migration, and invasion. Six circular RNAs (circ-FAM158A, circ-DHDDS, circ-E2F3, circ-TRHDE, circ-E2F5, and circ-RNF20) promote disease progression and metastasis in retinoblastoma and function as oncogenic factors. Other circular RNAs, such as circ-TET1, circ-SHPRH, circ-MKLN1, and circ-CUL2, play tumor suppressive roles in retinoblastoma. At present, the studies on the regulatory mechanism of circular RNAs in retinoblastoma are not very clear. The purpose of this review is to summarize recent studies on the functional roles and molecular mechanisms of circular RNAs in retinoblastoma and highlight novel strategies for retinoblastoma diagnosis, prognosis, and treatment.

Retinoblastoma in an older child with secondary glaucoma as the first clinical presenting symptom: A case report

BACKGROUND

Retinoblastoma (Rb) is primarily found in infants or young children. The most common primary presenting sign of Rb is leukocoria. Rb is very rare in children who are 10 years old or older. Timely and correct diagnosis as well as proper treatment are the key factors affecting the prognosis of Rb.

CASE SUMMARY

A 10-year-old girl with symptoms of vision loss, redness, swelling and pain in the right eye for 2 mo was admitted to our Department of Ophthalmology. The visual acuity of the right eye was graded as hand movement. The intraocular pressure of the eye was 46.9 mmHg. No substantial space-occupying lesion or characteristic calcified plaque was found in the eye. The patient underwent anterior chamber irrigation under general anesthesia on the same day of admission, and 2 mL of irrigation solution was saved for pathological examination. Histopathological examination of the anterior chamber fluid revealed cancer cells. A diagnosis of Rb with masquerade syndrome was made. The patient underwent enucleation followed by 6 rounds of systematic chemotherapy. A follow-up examination almost 9 years later found no relapse of Rb.

CONCLUSION

For older pediatric patients who have secondary glaucoma and uveitis symptoms without a clear cause of the disease and have no space-occupying lesion found by imaging examination, aqueous humor or vitreous humor examination is recommended for timely and correct diagnosis and appropriate treatment.

Spectrum of ophthalmic diseases in children hospitalized in a tertiary ophthalmology hospital in China from 2010 to 2019

BACKGROUND

Describing the pattern of pediatric eye diseases is necessary for appropriate eye care in children. This study explored the spectrum and characteristics of pediatric ophthalmic diseases in a typical tertiary ophthalmology hospital in China.

METHODS

A retrospective study was conducted at a tertiary ophthalmology hospital between 2010 and 2019 in Guangzhou, China. This study included 44,552 inpatients who were younger than 18 years old. Demographic and diagnostic data were collected from the electronic medical record system. Multiphase regression analysis was used to estimate trends in the annual percentages of ten common ophthalmic diseases.

RESULTS

From 2010 to 2019, 44,552 inpatients met the inclusion criteria. The majority were male (61.9%), aged 7 to 12 years (30.3%) and self-paying (56.6%). The top ten conditions were refractive error (41.2%), strabismus (36.1%), cataract (13.6%), trauma (11.8%), congenital ptosis (8.8%), tumor (8.1%), amblyopia (7.1%), glaucoma (7.0%), entropion and trichiasis of eyelid (7.0%), and retinal detachment (6.5%). The annual percentage changes (APCs) for refractive error, strabismus, and retinal detachment were 9.3% (95% CI, 8.1-10.5%), 4.7% (95% CI, 3.8-5.6%) and - 2.8% (95% CI, - 5.1% to - 0.4%) respectively. For trauma, the average APC (AAPC = -9.2%, (95% CI, - 12.1% to - 6.2%) decreased gradually from 2010 to 2015 (APC = -4.2% (95% CI, - 8.8-0.7%)) and decreased rapidly from 2015 to 2019 (APC = -15.1% (95% CI, - 21.0% to - 8.7%)).

CONCLUSIONS

Pediatric ophthalmic diseases are common in China. Preventive strategies and health education aimed at the prevention of refractive error, strabismus, and entropion and trichiasis of eyelid will be crucial in reducing the burden of pediatric ophthalmic diseases on health care systems and human development.

circRNF20 aggravates the malignancy of retinoblastoma depending on the regulation of miR-132-3p/PAX6 axis

Circular RNAs (circRNAs) serve as essential players in diverse human cancers, including retinoblastoma (RB). In this study, the function of circRNA Ring Finger Protein 20 (circRNF20) in RB progression was investigated. Quantitative real-time polymerase chain reaction, western blot assay or immunohistochemistry assay was performed to determine the expression of circRNF20, miR-132-3p and Paired Box 6 (PAX6). Dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay were utilized to verify the relationships among circRNF20, miR-132-3p and PAX6. In vivo experiment was done for circRNF20 function in tumor formation. It was found that ircRNF20 level was increased in RB tissues and linked to advanced tumor, nodes, metastases (TNM) stage and poor overall survival rate. Deficiency of circRNF20 suppressed cell proliferation, migration and invasion and induced apoptosis in vitro, as well as blocked tumor growth in vivo. circRNF20 directly targeted miR-132-3p and miR-132-3p overexpression inhibited RB cell progression. PAX6 was the target gene of miR-132-3p. Moreover, miR-132-3p inhibition or PAX6 overexpression reversed circRNF20 deficiency-mediated effects on RB cell malignant behaviors. In addition, exosomal circRNF20 was able to promote RB cell progression. Thus, we concluded that circRNF20 served as an oncogene in RB progression through the circRNF20/miR-132-3p/PAX6 pathway.

Applications of Non-Coding RNAs in Patients With Retinoblastoma

Retinoblastoma (RB) is the most common primary intraocular malignancy in childhood. In the carcinogenic process of neoplasms such as RB, the role of non-coding RNAs (ncRNAs) has been widely demonstrated recently. In this review, we aim to provide a clinical overview of the current knowledge regarding ncRNAs in relation to RB. Although ncRNAs are now considered as potential diagnostic biomarkers, prognostic factors, and therapeutic targets, further studies will facilitate enhanced understanding of ncRNAs in RB physiopathology and define the roles ncRNAs can play in clinical practice.

High-Risk Histopathologic Features of Retinoblastoma Treated at a Tertiary Hospital in West Java, Indonesia

PURPOSE

To evaluate the histopathological characteristics of clinically advanced retinoblastoma (RB) and its relationship with tumor differentiation.

METHODS

This was a cross-sectional study of primary enucleated group D/E intraocular RB using medical records from 2017 to 2020 in a tertiary referral hospital. Cases with incomplete histopathological results were excluded. Tumors were classified into well, moderately, and poorly differentiated and undifferentiated. High-risk histopathological features were classified as per Thaung and Karaa [Community Eye Health. 2018;31(101):17-3].

RESULTS

This study included 121 patients (129 eyes), of which 32.2% were diagnosed at 25-36 months. High-risk features (HRFs) were found in 100/129 eyes, and of 73 complete histopathological results, the 2 most common HRFs were postlaminar optic nerve invasion and massive choroidal invasion. RB was poorly differentiated in 69.9% and well differentiated in 12.3% of eyes. There was no statistically significant association between any HRFs and tumor differentiation, with age >2 years associated with tumor differentiation (p < 0.05).

CONCLUSION

The frequency of HRFs is 77.5% of primary enucleated eyes, mainly poorly and undifferentiated cells, particularly in children aged >2 years old.

A high-risk retinoblastoma subtype with stemness features, dedifferentiated cone states and neuronal/ganglion cell gene expression

Retinoblastoma is the most frequent intraocular malignancy in children, originating from a maturing cone precursor in the developing retina. Little is known on the molecular basis underlying the biological and clinical behavior of this cancer. Here, using multi-omics data, we demonstrate the existence of two retinoblastoma subtypes. Subtype 1, of earlier onset, includes most of the heritable forms. It harbors few genetic alterations other than the initiating RB1 inactivation and corresponds to differentiated tumors expressing mature cone markers. By contrast, subtype 2 tumors harbor frequent recurrent genetic alterations including MYCN-amplification. They express markers of less differentiated cone together with neuronal/ganglion cell markers with marked inter- and intra-tumor heterogeneity. The cone dedifferentiation in subtype 2 is associated with stemness features including low immune and interferon response, E2F and MYC/MYCN activation and a higher propensity for metastasis. The recognition of these two subtypes, one maintaining a cone-differentiated state, and the other, more aggressive, associated with cone dedifferentiation and expression of neuronal markers, opens up important biological and clinical perspectives for retinoblastomas.

Therapeutic Targeting PLK1 by ON-01910.Na Is Effective in Local Treatment of Retinoblastoma

Cell cycle deregulation is involved in the pathogenesis of many cancers and is often associated with protein kinase aberrations, including the polo-like kinase 1 (PLK1). We used retinoblastoma, an intraocular malignancy that lacks targeted therapy, as a disease model and set out to reveal targetability of PLK1 with a small molecular inhibitor ON-01910.Na. First, transcriptomic analysis on patient retinoblastoma tissues suggested that cell cycle progression was deregulated and confirmed that PLK1 pathway was upregulated. Next, antitumor activity of ON-01910.Na was investigated in both cellular and animal levels. Cytotoxicity induced by ON-01910.Na was tumor specific and dose dependent in retinoblastoma cells, while nontumor cells were minimally affected. In three-dimensional culture, ON-01910.Na demonstrated efficient drug penetrability with multilayer cell death. Posttreatment transcriptomic findings revealed that cell cycle arrest and MAPK cascade activation were induced following PLK1 inhibition and eventually resulted in apoptotic cell death. In Balb/c nude mice, a safe threshold of 0.8 nmol intravitreal dosage of ON-01910.Na was established for intraocular safety, which was demonstrated by structural integrity and functional preservation. Furthermore, intraocular and subcutaneous xenograft were significantly reduced with ON-01910.Na treatments. For the first time, we demonstrated targetability of PLK1 in retinoblastoma by efficiently causing cell cycle arrest and apoptosis. Our study is supportive that local treatment of ON-01910.Na may be a novel, effective modality benefiting patients with PLK1-aberrant tumors.

Correlation between Family RB1 Gene Pathogenic Variant with Clinical Features and Prognosis of Retinoblastoma under 5 Years Old

Retinoblastoma (RB) is the most common primary intraocular malignant tumor in infants and the prototype of human hereditary tumors. Its occurrence and development are closely related to the pathogenic variant of tumor suppressor RB1 gene. We aim to analyze the characteristics of RB1 gene pathogenic variant and clinical phenotype in retinoblastoma patients and their relatives. Children with RB were recruited from August 2007 to November 2017. QT-PCR, probing, and gene sequencing were used to analyze the sequence of RB1 gene in RB children, their parents, or grandparents with a clear history of illness. The SPSS20.0 software was used to analyze the correlation between polymorphisms of RB1 gene and the incidence and prognosis of the enrolled children and relatives. 40 RB children (20 males and 20 females) were recruited, unilateral RB accounted for 52.5% (21/40), bilateral RB accounted for 42.5% (17/40), and trilateral RB accounted for 5.0% (2/40). 6 patients had a clear family history (15.0%, 6/40). It had been verified that 19 probands (47.5%) have RB1 gene pathogenic variants (11 frameshift and 8 missense pathogenic variants), of which germline inheritance accounted for 47.4% (9/19) and nongermline heredity accounted for 52.6% (10/19). Pathogenic variants of 10 nucleic acid sites without reported were found, among which c.2455C>G (p.L819V) was confirmed to have heterozygous pathogenic variants in both a bilateral RB patient and his mother with unilateral RB. Family genetic high-risk factors, bilateral/trilateral RB, >12-month-onset RB have a higher proportion of RB1 gene pathogenic variant than children with no family history, unilateral RB, and ≤12-month (P = 0.021, 0.001,0.034). The proportion of pedigree inheritance of infantile retinoblastoma with bilateral disease is high. There was a certain proportion of RB1 gene pathogenic variant in 3-5-year-old children with bilateral RB, even if they had no family genetic history. Therefore, the detection of RB1 gene pathogenic variant should not only focus on infants but also on the phenotype of RB1 gene pathogenic variant in children over 3 years old with bilateral eye disease.

Clinical evaluation of RB1 genetic testing reveals novel mutations in Vietnamese patients with retinoblastoma

Clinical evaluation of the genetic testing strategy is essential for ensuring the correct determination of mutation carriers. The current study retrospectively analyzed genetic and clinicopathological data from 62 Vietnamese patients with retinoblastoma (RB) referred to the Vinmec Hi-Tech Center for RB transcriptional corepressor 1 (RB1) genetic testing between 2017 and 2019. The present study aimed to evaluate the sensitivity of the Next Generation Sequencing (NGS) method to identify novel RB1 mutations, and to consider using age at diagnosis as a risk factor. Genomic DNA was analyzed with custom panel based targeted NGS. NGS was performed on the Beijing Genomics Institute (BGI) sequencing platform, and pathogenic or likely pathogenic variants were confirmed by Sanger sequencing, quantitative PCR (qPCR) or Multiplex Ligation-dependent Probe Amplification assay (MLPA). Constitutional RB1 variants were identified in 100% (25/25) of the bilateral cases, while several common previously reported RB1 mutations were also recorded. In addition, in Vietnamese patients with RB, nine novel RB1 mutations were identified. Children aged between 0-36 months were more likely to be RB1 carriers compared with those aged >36 months. The current findings indicated that the NGS method implemented in the Vinmec Hi-Tech Center was highly accurate, and age at diagnosis may be used to assess the risk of hereditary RB. Furthermore, the newly identified RB1 mutations may provide additional data to improve the current understanding of the mechanisms underlying RB1 inactivation and the development of rapid assays for detecting RB1 mutations. Overall, the present study suggested that NGS may be applied for detecting germline RB1 mutations in routine clinical practice.

Prenatal diagnosis of bilateral retinoblastomas by multimodality fetal imaging: case report and review of the literature

Retinoblastoma is the prototypic genetic tumor. Caused by mutations in the RB1 gene, retinoblastomas are heritable in 40% of the cases and, in such cases, tumors are bilateral in 80%, unilateral in 15%, and trilateral in 5% of the cases. Trilateral retinoblastoma is a term that describes bilateral retinoblastomas plus a midline suprasellar or pineal neuroectodermal tumor. Patients with a germline RB1 mutation have 45% chance of having an offspring with retinoblastoma. Prenatal diagnosis is important because the doubling time is fast, ranging from 7 to 15 days. Thus, late diagnosis during infancy is associated with larger tumors and increased risk of death, need for globe enucleation and vision loss. We report a case of bilateral retinoblastomas diagnosed by targeted high-resolution ultrasonography of the orbits at 32 weeks of gestation in a patient at risk. This report demonstrates the feasibility of accurately detecting even tiny retinoblastomas by ultrasound with current technology. We also review prenatally published cases to date and comment on the technical strengths and limitations of ultrasound and fetal MRI for prenatal diagnosis of retinoblastomas.

lncRNA RHPN1-AS1 Serves as a Sponge for miR-3133 Modulating the Cell Proliferation of Retinoblastoma through JAK2

Purpose

To investigate the effects of lncRNA RHPN1-AS1 on retinoblastoma (RB) and further explore its underlying molecular mechanisms.

Methods

The expression of RHPN1-AS1, miR-3133, (JAK2), and signal transducer and activator of transcription 3 (STAT3) was detected by qRT-PCR. CCK-8, EDU, and flow cytometry assays were conducted to assess the proliferation activity and apoptosis of RB cells. Double fluorescein and RNA immunoprecipitation assays were performed to detect the interaction between RHPN1-AS1 and miR-3133 or miR-3133 and JAK2. Western blotting was performed to detect the expression of apoptosis-related proteins.

Results

In RB cells, RHPN1-AS1 was upregulated. Silencing RHPN1-AS1 inhibited the activity of RB cells and promoted apoptosis. The expressions of proapoptotic factors (Bax and p53) were increased, while antiapoptotic factors (Bcl-2 and Survivin) were suppressed in siRHPN1-AS1 groups. Furthermore, we predicted and verified that RHPN1-AS1 regulated RB progression by targeting miR-3133/JAK2. In addition, siRHPN1-AS1 also inhibited oncogene STAT3 protein expression.

Conclusion

lncRNA RHPN1-AS1 served as a sponge for miR-3133 to counteract miR-3133-mediated JAK2/STAT3 suppression, indicating that the lncRNA RHPN1-AS1 may be a potential therapeutic target for the treatment of RB.

Next generation sequencing of RB1gene for the molecular diagnosis of ethnic minority with retinoblastoma in Yunnan

Background

Retinoblastoma is a rare intraocular malignancy and typically initiated by inactivating biallelic mutations of RB1 gene. Each year, ~ 8000 children worldwide are diagnosed for retinoblastoma. In high-income countries, patient survival is over 95% while low-income countries is ~ 30%.If disease is diagnosed early and treated in centers specializing in retinoblastoma, the survival might exceed 95% and many eyes could be safely treated and support a lifetime of good vision. In China, approximate 1100 newly diagnosed cases are expected annually and 28 hospitals covering 25 provinces established centers classified by expertise and resources for better treatment options and follow-up. Comparing with other province of eastern China, Yunnan province is remote geographically. This might result that healthcare staff have low awareness of the role of genetic testing in management and screening in families.

Methods

The patients with retinoblastoma were selected in Yunnan. DNA from blood was used for targeted gene sequencing. Then, an in-house bioinformatics pipeline was done to detect both single nucleotide variants and small insertions/deletions. The pathogenic mutations were identified and further confirmed by conventional methods and cosegregation in families.

Results

Using our approach, targeted next generation sequencing was used to detect the mutation of these 12 probands. Bioinformatic predictions showed that nine mutations were found in our study and four were novel pathogenic variants in these nine mutations.

Conclusions

It’s the first report to describe RB1 mutations in Yunnan children with retinoblastoma. This study would improve role of genetic testing for management and family screening.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12881-020-01150-7.

Unilateral Leukocoria in an Infant

A nine-day-old male infant presents with his mother to the pediatric clinic with a concern of a white spot in his right eye. There was no history of antenatal or perinatal complications and the mother's serology was negative. Physical examination was remarkable only for leukocoria in the right eye. He was evaluated to have a Mittendorf dot. This is a benign clinical finding. Pupillary reflex check is an important part of a physical examination which can recognise pathological conditions such as cataract, retinoblastoma, metabolic errors with ocular manifestations and lead to early treatment before the child loses vision.

Liquid Biopsy for Solid Ophthalmic Malignancies: An Updated Review and Perspectives

Simple Summary

To date, there is no treatment for metastatic uveal melanoma. Identifying its metastatic spread is essential. Liquid biopsy can identify patients at risk of metastatic spread early. Here, we aim to summarize the current knowledge of liquid biopsy in ophthalmic malignant tumors, including uveal melanoma. Our objective is to establish the current state of liquid biopsy in the ophthalmic field, as well as its perspectives and limitations.

Abstract

Tissue biopsy is considered the gold standard when establishing a diagnosis of cancer. However, tissue biopsies of intraocular ophthalmic malignancies are hard to collect and are thought to be associated with a non-negligible risk of extraocular dissemination. Recently, the liquid biopsy (LB) has emerged as a viable, non-invasive, repeatable, and promising way of obtaining a diagnosis, prognosis, and theragnosis of patients with solid tumors. LB refers to blood, as well as any human liquid. The natural history of uveal melanoma (UM) and retinoblastoma (RB) are radically opposed. On the one hand, UM is known to disseminate through the bloodstream, and is, therefore, more accessible to systemic venous liquid biopsy. On the other hand, RB rarely disseminates hematogenous, and is, therefore, more accessible to local liquid biopsy by performing an anterior chamber puncture. In this review, we summarize the current knowledge concerning LB in UM, RB, conjunctival tumors, and choroidal metastases. We also develop the current limitations encountered, as well as the perspectives.

Molecular Genetics of Intraocular Tumors

PURPOSE

To explore the value of molecular technologies in the pathologic evaluation, diagnosis, and treatment of retinoblastoma and uveal melanoma.

METHODS

Review of the peer-reviewed literature on the molecular pathology of primary intraocular tumors.

CONCLUSION

Molecular tests are playing an increasingly important role in the diagnosis of intraocular tumors. They provide information valuable for diagnosis, prognosis, screening regimens, genetic counselling, and treatment. These technologies are becoming easier, faster, and with higher sensitivity and accuracy.

Different transcriptome profiles between human retinoblastoma Y79 cells and an etoposide-resistant subline reveal a chemoresistance mechanism

Background

Retinoblastoma (RB) is the most frequent pediatric retinal tumor. In the present study, to elucidate chemoresistance mechanisms and identify potential biomarkers in RB, we utilized RNA sequencing (RNAseq) technological platforms to reveal transcriptome profiles and identify any differentially expressed genes (DEGs) between an etoposide drug-resistant subline (Y79/EDR) and parental Y79 cells.

Methods

To test whether Y79/EDR cells showed resistance to antineoplastic agents for RB, we treated the cells with etoposide, carboplatin and vincristine and analyzed them with a Cell Counting Kit-8 (CCK-8). Y79/EDR and parental Y79 cells were used for RNAseq and bioinformatics analysis to enable a genome-wide review of DEGs between the two lines using the DESeq R package (1.10.1). Then, DEG enrichment in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways was analyzed with KOBAS software. Next, real-time quantitative reverse transcription polymerase chain reaction (real time QRT-PCR) and cytotoxicity assays were performed to experimentally and functionally validate the identified candidate biomarkers.

Results

Y79/EDR cells showed resistance to etoposide, carboplatin and vincristine at different concentrations. In total, 524 transcripts were differentially expressed in Y79/EDR cells based on analysis of fragments per kilobase of transcript per million fragments mapped (FPKM); among these, 57 genes were downregulated and 467 genes were upregulated in Y79/EDR cells compared to parental Y79 cells. We selected candidate DEGs, including ARHGAP9, HIST1H4H, RELN, DDIT4, HK2, STC1 and PFKFB4, for mRNA expression validation with real time QRT-PCR assays and found that the expression levels determined by real time QRT-PCR were consistent with the RNAseq data. Further studies involving downregulation of ARHGAP9 with a specific siRNA showed that ARHGAP9 altered the cellular sensitivity of Y79 cells to etoposide and carboplatin.

Conclusion

Our initial findings provided a genomic view of the transcription profiles of etoposide-induced acquired resistance in RB. Follow-up studies indicated that ARHGAP9 might be a chemoresistance biomarker in RB, providing insight into potential therapeutic targets for overcoming acquired chemoresistance in RB. These findings can aid in understanding and overcoming chemoresistance during treatment of RB in the clinic.

Update on pathology of retinoblastoma

Retinoblastoma is caused by mutational inactivation of both alleles of the RB1 gene, which maps to chromosome 13q14 and encodes retinoblastoma protein that acts as a tumor suppressor. Histopathological high-risk features of retinoblastoma are predictive of metastasis or local recurrence. The focus of this update is to emphasize the recent advances in pathology, various molecular key pathways and genome wide approaches for newer potential therapeutic future targets associated with retinoblastoma tumor biology. This review article highlights the new biomarkers expressed by the retinoblastoma tumor for the better survival of patients.

Expression profiles and prognostic value of miRNAs in retinoblastoma

Current cure rates for retinoblastoma (RB) are very high in developed countries. Nonetheless, in less privileged places worldwide, delayed diagnosis and refusal to adhere to treatment still endure an obstacle to improve overall patient survival. Thus, the access to consistent biomarkers for diagnosis at an earlier stage may facilitate treatment and improve outcomes. Over recent years, much attention has been focused on miRNAs, key post-transcriptional regulators that when altered, largely contribute to carcinogenesis and tumor progression. Many of the ~ 2500 microRNAs described in humans have shown differential expression profiles in tumors. In this review, we summarize current data about the roles of miRNAs in RB along with their value as diagnostic/prognostic factors using electronic databases such as PubMed. We reviewed the importance of miRNA in RB biology and discussed their implications in clinic intervention. Several miRNAs have pointed out reliable diagnostic and prognostic molecular biomarkers. The emergence of targeted therapies has significantly improved cancer treatment. In the near future, the modulation of miRNAs will represent a good treatment strategy.