Previous CHECT research

CHECT photo - retinoblastoma past research

Previous CHECT funded retinoblastoma research projects

These projects have previously been funded by CHECT. For latest research please have a look at our current retinoblastoma research page.

Validation of Molecular Targets Characterizing Invasive Retinoblastoma

Project leader: Richard L. Hurwitz, MD, FARVO
Award: £39,756
Duration: Three years, May 2014

Summary

Although almost all children with retinoblastoma have mutations in the RB1 gene, not all children have invasive disease, a precursor to the development of metastatic disease. We hypothesize that by comparing gene expression in tumours derived from children with invasive retinoblastoma to tumours derived from children with noninvasive retinoblastoma, we can gain an understanding of the metabolic steps after the mutation of RB1 that lead to tumour invasion and subsequent metastatic disease.

We have studied gene expression in both invasive and noninvasive retinoblastoma tumours using next generation RNA-Seq technology and have identified 50 candidate genes that are more highly expressed in invasive retinoblastoma tumours when compared to noninvasive retinoblastoma tumours. We propose to validate these candidate genes by examining differences between non-invasive and invasive retinoblastoma tumours using in vitro and in vivo models of retinoblastoma as well as tumour samples from children. The advantages of studying retinoblastoma are 1) lack of complications caused by age or environmental exposures, 2) known molecular initiating events and 3) relatively rapid tumour initiation and progression.

The results obtained will help stratify risk for metastasis, identify new therapeutic targets for retinoblastoma and improve approaches to genetic counselling of affected families.

Status: Project completed

Investigation of the mutational landscape of retinoblastoma

Project leader: Dr Carmel McConville
Award: £15,000 joint funding CHECT and Fight for Sight; additional £14,200 CHECT
Duration: One year, May 2014

Summary

We have established cell lines from 15 different retinoblastomas and these represent one of the largest collections of retinoblastoma cell lines worldwide.

We will use the latest technology, known as ‘next generation sequencing’, to look at the DNA sequence of every active gene in these retinoblastoma cell lines. This sequence will be compared to a normal reference sequence in order to identify genes which are mutated. The sequence analysis will indicate which genes which are most frequently mutated in retinoblastoma and will also show how the overall cellular genetic activity is influenced by these mutated genes.

All of this information is essential to inform future research into the development of novel targeted therapeutics capable of reversing the effects of mutated genes in retinoblastoma.

Status: Project complete, awaiting final report

Role of SLRP family members in malignant progression of retinoblastoma.

Project Leader Professor: Shin-ichi Ohnuma Co-investigator: Dr Mandeep Sagoo
Award: £15,000 Joint funding CHECT and Fight for Sight
Duration: One year from April 2014

Summary

This project will investigate the role of a family of genes, which produce secreted proteins around the cancer cells, because this family of proteins is highly produced in the normal eye and known to be involved in formation of non-eye cancers. Moreover, our previous studies using cells isolated from retinoblastoma patients showed that amounts of some members of this protein family are altered in association with retinoblastoma development.

Firstly, we will examine the change of gene expression in the process of retinoblastoma development using human retinoblastoma tissues. Then we will examine their function and how they affect retinoblastoma progression using cells isolated from retinoblastoma tissues.

If we can prove the importance of the gene family in retinoblastoma, it may become possible to develop new methods of diagnosis and treatment for retinoblastoma.

Status: Project complete

Retinal vessel architecture in retinoblastoma patients – a predictor of progression?

Project Leader: Dr Clare Wilson
Award: £10,500
Duration: August 2013

Summary

Retinoblastoma treatment has developed leading to vastly improved survival rates. However, detecting early disease progression is challenging for experienced retinoblastoma surgeons who see over 20 new patients a year. It is even more problematic for surgeons working in countries with smaller populations. An objective assessment that can alert the surgeon to progression of the cancer would be of great benefit.

New software can measure changes in blood vessels at the back of the eye. Eye cancer doctors have made the clinical observation that these vessels change when disease worsens, and so could be used to detect eye needing more treatment. At The Royal London Hospital we have a large set of digital images from children who have had eye cancer and we are analysing them with new software to see if the vessel changes can be used to accurately detect progression of the tumour.

If we get positive results, we could make the follow up visits for these children with eye cancer a more pleasant experience, yet just as accurate.

Status: Project complete, awaiting final report

Use of aptamers to increase the efficacy of HMGA2 targeted therapy in retinoblastoma

Project Leader: Dr S Krishnakumar
Award: £47,298
Duration: Two years, April 2014

Summary

With advancements in molecular biology, targeted therapy is gaining importance in the treatment of Rb. Aptamers have immense potential in targeted therapy because of their ability to bind to the target with high affinity and specificity. Previous findings show over-expression of the transcription factor HMGA2 in retinoblastoma transformation. Our previous work also showed the contribution of HMGA2 in cell proliferation and G1/S phase transition in Rb.

HMGA2 was also found to regulate many oncogenic and tumour suppressive miRNAs in Rb. siRNA and aptamer targeting HMGA2 were able to bring down the proliferation in Rb. But these biomolecules targeting HMGA2 should reach the tumour cells to modulate HMGA2 function with minimal uptake and damage to the normal cells.

In the present proposal, we would like to develop strategies for delivering the HMGA2 siRNA and aptamer targeting HMGA2 to the retinoblastoma cells. Tumour cell specific delivery of the aptamer and siRNA sparing the non-cancerous cell would be the first parameter to be evaluated. We would also investigate that the delivery strategies do not compromise the affinity, stability and functional effect of the siRNA and aptamer targeting HMGA2.

The two novel strategies proposed in this project are: delivery of HMGA2 siRNA through aptamer-siRNA chimeras into the retinoblastoma cells; and developing a novel antibody mediated delivery of aptamer into Rb cells.

Status: Project completed – final report summary and in full.

Epigenetic Mechanisms in Retinoblastoma Tumourigenesis

Project Leader: Dr Carmel McConville at the CRUK Institute for Cancer Studies at the University of Birmingham.
Award: £50,500
Duration: One year from February 2012

Summary

It is known that a gene called ‘DEK’ is present at abnormally high levels in approximately 50% of cases of retinoblastoma. It is possible that DEK might contribute to the growth of the retinoblastoma and perhaps also to its spread outside the eye. It could therefore be a target for therapy in these retinoblastomas.

he purpose of this research is firstly to find out what effect DEK has on retinoblastoma cells and exactly how it works. This will be the key to developing new drugs to block its action.

Status: Project completed – final report here.

Development of a next generation sequencing analytical pathway for improved test sensitivity and enhanced detection of low level RB1 mutations in retinoblastoma patients.

Project Leader: Dr Simon Ramsden Co-investigator: Dr Sarah Waller
Award £13,810 Joint funding CHECT and Fight for Sight
Duration: One year from December 2013

Summary

Mutations in the retinoblastoma gene RB1 cause retinoblastoma. Traditional Sanger sequencing technology reliably detects mutations in RB1 in tumour tissue in the majority of patients from whom tumour is available, and detection of a germline mutation permits predictive testing of at risk family members. In our laboratory Sanger sequencing detects germline mutations in ~92% of patients with bilateral tumours and ~16% of patients with unilateral tumours.

Whilst Sanger sequencing offers appropriate test sensitivity for most cases there remain a small number of undetected familial mutations and also it has limited utility when trying to detect mosaicism. Emerging sequencing technologies (so called “Next Generation”) are showing great promise in both the academic and service environment and offer significant advantages over conventional Sanger testing. We feel that Next Generation Sequencing could offer us a means of overcoming both of these obstacles.

Status: Project completed – final report here.

Identification of molecular tools

Project Leader: Dr Carmel McConville at the CRUK Institute for Cancer Studies at the University of Birmingham.
Award: £70,000
Duration: Three years from Oct 2009

Summary
Survival rates for retinoblastoma in the UK are well in excess of 90% and the challenge in treating this disease is to maximize preservation of sight whilst minimizing the risk of recurrent disease and treatment-related toxicity. The purpose of this project is to provide a molecular characterisation of retinoblastoma which will allow a more informed approach to balancing these twin objectives.

Status: Project completed – summary of final report here.

Audit of clinical genetic and molecular genetic information and reproductive issues known to retinoblastoma families.

Project Leader: Dr Trevor Cole, Consultant Clinical Geneticist, Birmingham Women’s Hospital
Award: £30,000
Duration: Two years from October 2008. The project overran and finished in late 2012, we await a final report.

Summary

The differing and complex genetics underlying the majority of unilateral and bilateral retinoblastoma means that many families have to be given genetic counselling advice on an ongoing and rather piecemeal basis. We therefore suggest that we need to work with families currently undergoing treatment and, families discharged from follow up, to see if further genetic counselling input is necessarily to ensure families have the best information we are currently able to provide.

We would suggest that this is important baseline data and would facilitate periodic review or audit that is likely to be necessary until all families are able to have a “definitive genetic explanation” to all at risk family members. Evidence on the practical benefits perceived by patients, in addition to the theoretical medical and cost benefits reported by Richter et al 2003, from molecular studies could then be assessed. This study would be timely as it could collect data prospectively from families yet to have definitive molecular answers and subsequent to these answers becoming available.

Progress report (As written by Dr T Cole): In early 2012 attempts to contact the remaining list of people was drawn to a close and we decided at this stage all remaining contact would be via letters to the participants’ GPs. Since this time several hundred further patient replies have been reviewed and letters to GPs are being produced and sent out to the remaining families.

Status: Project complete, published article here.

The role of HMGA1 and HMGA2 in retinoblastoma

Project leader: Mr A M Reddy, Royal London Hospital
Duration: Six months 2005
Award: £4,817.33

Summary

The aim is to investigate the expression of HMGA1 and HMGA2 proteins in archival retinoblastoma tumours and whether the protein HMGA2 is expressed uniformly throughout the Rb tumours or there is a heterogeneous expression in the tumour samples. Also HMGA2 expression will be correlated with invasion of the tumours. The study will also generate data whether the HMGA1 protein is expressed in non-neoplastic retinal tissues. This has implications in damage to the non-neoplastic retinal tissues.

Status Project completed. The results from this project led to the funding of a subsequent project entitled ‘To study the RNAi mediated HMGA2 gene expression profile of y79 cells’ (see below)

To study the RNAi mediated HMGA2 gene expression profile of y79 cells

Project Leader: Prof Krishnakumar from the Sankara Nethralaya Centre in India and Mr Ashwin Reddy from the Royal London Hospital.
Award: £15,000
Duration: Three years

Summary

We still do not understand why some retinoblastoma tumours grow slowly and some are very aggressive. The more aggressive retinoblastoma tumours (invasive retinoblastoma) invade into the outer layers of the eye. We are aware that loss of the retinoblastoma protein initiates events with tumour development, but other proteins are also implicated.

This team has already shown that a protein called HMGA2 (High Mobility Group A2 protein) is produced more in tumours that are invasive (above).This project gives an explanation for this. When this protein is not produced, retinoblastoma cells stop growing. Therefore this protein appears to be very important for the growth of the tumour-forming cells.

The genes that make proteins for tumour effectiveness such as ‘stickiness’ to blood vessels are affected. A tumour with more ‘sticky’ proteins is likely to be more aggressive. Other genes that are important for tumours to work are also affected. This is more evidence that stopping HMGA2 from working may be beneficial for patients as the retinoblastoma tumours may stop growing. It also shows how complex the biological pathways are for retinoblastoma.

Status: Complete. Abstract of final report herefull free paper here.

Epidemiological studies of retinoblastoma with particular reference to the incidence of multiple primary tumours

Project leader Dr Gerald Draper, Childhood Cancer Research Group, Oxford
Award: £34,879 in collaboration with University of Oxford, Childhood Cancer Research Group
Duration: Three years April 2003 – March 2006.

Summary

The Childhood Cancer Research Group (CCRG) has records of virtually every case of retinoblastoma occurring in Great Britain during the past forty years, together with records of selected groups of cases in earlier years. This database is linkable to laboratory records relating to many of these cases, including, in particular, those held at the Retinoblastoma Screening Unit at St Bartholomew’s Hospital.

In addition, the group has access to pedigree data collected by other research workers and to international data on the incidence of retinoblastoma. It is proposed, within the CCRG’s ongoing programme of epidemiological research, to update earlier analyses of these data and to initiate others in three areas:

1. Multiple primary tumours
2. Risks to offspring and siblings
3. Incidence rates of retinoblastoma

Status: Two of the three stages complete, final report here.

Psychological consequences of treatment for Rb in young children

Project leader: Dr S Norgate
Duration: One year from October 2002
Award: £31,136.23

Summary
This project seeks to examine the psychological consequences of retinoblastoma and associated treatment in the under-fives.

Status: Project completed – final report here.

Retinoblastoma treated with primary chemotherapy alone: The significance of tumour size, location and age

Project lead: Mr D S Gombos

Summary

This project will evaluate how tumour size, retinal location and patient age affect the outcome of retinoblastoma foci treated with chemotherapy.

Status: Project completed 2001 – final report here.

1. Is tumour size predictive of response to chemotherapy? 2. Does laser hyperthermia of retinoblastoma foci increase the risk of vitreous seeding?

Project lead: Mr D S Gombos
Duration: 10 months from January 2000
Awarded: £10,152

Summary

Project 1: To evaluate whether the size of a tumour at diagnosis correlates with its response to chemotherapy. Is the size of a tumour at diagnosis predictive of its response to chemotherapy alone?

Project 2: To establish whether laser hyperthermia correlates with an increased risk of vitreous seeding.

Retinoblastoma RB1 gene mutation analysis: Molecular Genetic Study of Hereditary Retinoblastoma

Project leader: Dr Z Onadim
Duration: Three years from December 1997
Awarded: £91,989 in collaboration with Queen Mary & Westfield College

Summary

The aim of the study was to analyse mutations in patients predisposed to Rb to gain an insight into the mechanism of mutagenesis and to offer screening for carrier status.

Status: Project complete – lay summary of the final report here.

Development of retinoblastoma database

Project leader: Prof G Draper & Dr J Kingston
Duration: One year from May 1997
Awarded: £19,528

Status: Project completed – final report here.

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