Recurrent Somatic Chromosomal Abnormalities in Relapsed Extraocular Retinoblastoma

A human neural crest model reveals the developmental impact of neuroblastoma-associated chromosomal aberrations

Early childhood tumours arise from transformed embryonic cells, which often carry large copy number alterations (CNA). However, it remains unclear how CNAs contribute to embryonic tumourigenesis due to a lack of suitable models. Here we employ female human embryonic stem cell (hESC) differentiation and single-cell transcriptome and epigenome analysis to assess the effects of chromosome 17q/1q gains, which are prevalent in the embryonal tumour neuroblastoma (NB). We show that CNAs impair the specification of trunk neural crest (NC) cells and their sympathoadrenal derivatives, the putative cells-of-origin of NB. This effect is exacerbated upon overexpression of MYCN, whose amplification co-occurs with CNAs in NB. Moreover, CNAs potentiate the pro-tumourigenic effects of MYCN and mutant NC cells resemble NB cells in tumours. These changes correlate with a stepwise aberration of developmental transcription factor networks. Together, our results sketch a mechanistic framework for the CNA-driven initiation of embryonal tumours.

The importance of basic and translational research in caring for children with malignant solid tumors in Latin America

Objective

Basic and translational research in pediatric cancer are essential to improve patient care. To critically assess the developments achieved in these areas in Latin America, we systematically reviewed information published between 2013 and 2023.

Methods

Studies of basic and translational research performed by investigators in Latin America evaluating pediatric malignant solid and central nervous system tumors were retrieved from PubMed. Original articles published in English between 2013 and 2023 were included. Collaborations among Latin American authors or among Latin American authors working with researchers from other continents were also included. Studies were excluded if they focused only on adults or on basic research in tumor biology not specifically related to the tumor types analyzed in this review.

Results

A total of 550 articles were retrieved, but after removal of duplicates, 514 articles were included in the analysis, the majority of which were authored by researchers affiliated with institutions in Argentina, Brazil and Mexico. These countries also had the highest number of collaborations on original articles published with authors from Europe and North America. Argentina had the highest number of collaborations on original publications, with coauthors from Brazil and Uruguay. The median impact factor of the 244 journals in which articles were published was 3.5. The most commonly studied tumors were osteosarcomas, neuroblastomas and medulloblastomas; the most commonly studied areas were molecular analysis, tumor cell biology and biomarkers.

Conclusions

In Latin America, research in pediatric oncology is on the agenda, despite a notable disparity in publication rates and frequency of collaboration between countries. There is a need to strengthen scientific collaboration within Latin America and with countries from other continents to promote research and to develop novel treatment strategies that reflect the local needs of children in Latin America who have solid tumors and brain cancer.

Correlating somatic copy number alteration in aqueous humour cfDNA with chemotherapy history, eye salvage and pathological features in retinoblastoma

BackgroundThis study determined to probe the potential association between somatic copy number alteration (SCNA) in retinoblastoma (RB) aqueous humour (AH) and pathological high-risk factors, clinical features and previous chemotherapy history.

METHODS

Single-centre retrospective cohort study from including 58 AH samples collected from 58 patients diagnosed. Among them, 41 samples were collected after enucleation and 17 samples were collected before intravitreal chemotherapy. SCNAs were accessed by conducting shallow whole-genome sequencing in cell-free (cf) DNA of AH. HRs and ORs were applied to measure risk factors.

RESULTS

Canonical RB SCNAs including 1q gain (87%), 2p gain (50%), 6p gain (76%), 16q loss (69%) were frequently detected. Non-classical RB SCNAs in AH including 17q gain (53%), 19q loss (43%), 7q gain (35%) were also commonly observed. 19q loss was significantly more common in patients with cT3c or worse stage than others (p=0.034). 2p gain(p=0.001) and 7q gain(p=0.001) were both more common in patients with primary enucleation than those with previous chemotherapy. Interestingly, both 2p gain (HR=1.933, p=0.027) and 7q gain (HR=2.394, p=0.005) might predict enucleation. Correlation analysis with pathological features among enucleated eyes showed that 19q loss can predict a higher risk for both massive choroid invasion (OR=4.909, p=0.038) and postlaminar optic nerve invasion (OR=4.250, p=0.043).

DISCUSSION

Sequencing of AH cfDNA in RB can provide sufficient in vivo information. 19q loss was a potential signature of advanced cases clinically and pathologically.Repeated sampling from eyes receiving sequential chemotherapy should be conducted to evaluate fluctuation of SCNA in future study.

Establishment and Comprehensive Characterization of a Novel Preclinical Platform of Metastatic Retinoblastoma for Therapeutic Developments

Purpose

Although there have been improvements in the management of metastatic retinoblastoma, most patients do not survive, and all patients suffer from multiple short- and long-term treatment toxicities. Reliable and informative models to assist clinicians are needed. Thus we developed and comprehensively characterized a novel preclinical platform of primary cell cultures and xenograft models of metastatic retinoblastoma to provide insights into the molecular biology underlying metastases and to perform drug screening for the identification of hit candidates with the highest potential for clinical translation.

Methods

Orbital tumor, bone marrow, cerebrospinal fluid, and lymph node tumor infiltration specimens were obtained from seven patients with metastatic retinoblastoma at diagnosis, disease progression, or relapse. Tumor specimens were engrafted in immunodeficient animals, and primary cell lines were established. Genomic, immunohistochemical/immunocytochemical, and pharmacological analysis were performed.

Results

We successfully established five primary cell lines: two derived from leptomeningeal, two from orbital, and one from lymph node tumor dissemination. After the intravitreal or intraventricular inoculation of these cells, we established cell-derived xenograft models. Both primary cell lines and xenografts accurately retained the histological and genomic features of the tumors from which they were derived and faithfully recapitulated the dissemination patterns and pharmacological sensitivity observed in the matched patients.

Conclusions

Ours is an innovative and thoroughly characterized preclinical platform of metastatic retinoblastoma developed for the understanding of tumor biology of this highly aggressive tumor and has the potential to identify drug candidates to treat patients who currently lack effective treatment options.

Transcriptome analysis reveals molecularly distinct subtypes in retinoblastoma

Retinoblastoma is the most frequent intraocular malignancy in children. Little is known on the molecular basis underlying the biological and clinical behavior of this cancer. Here, using gene expression profiles, we demonstrate the existence of two major retinoblastoma subtypes that can be divided into six subgroups. Subtype 1 has higher expression of cone related genes and higher percentage of RB1 germline mutation. By contrast, subtype 2 tumors harbor more genes with ganglion/neuronal features. The dedifferentiation in subtype 2 is associated with stemness features including low immune infiltration. Gene Otology analysis demonstrates that immune response regulations and visual related pathways are the key molecular difference between subtypes. Subtype 1b has the highest risk of invasiveness across all subtypes. The recognition of these molecular subtypes shed a light on the important biological and clinical perspectives for retinoblastomas.

Causes of death and survival analysis for patients with retinoblastoma in Jordan

Purpose

To analyze causes and prognostic factors for death among Retinoblastoma (Rb) patients treated at a single specialized tertiary cancer center in Jordan.

Methods

We reviewed the mortality causes for all Rb patients who have been treated at the King Hussein Cancer Center between 2003 and 2019 and were followed for at least 3 years after diagnosis. The main outcome measures included demographics, laterality, tumor stage, treatment modalities, metastasis, survival, and causes of death.

Results

Twenty-four (5%) of the 478 patients died from retinoblastoma and 5-year survival was 94%. The mean age at diagnosis was 15 months (median, 18 months; range, 4-38 months); eight (33%) received diagnoses within the first year of life. Eleven (46%) were boys, 16 (67%) had bilateral disease, and 3 (13%) had a positive family history. The stage for the worst eye was C for 1 (4%) patient, D in 6 (25%) patients, and E (T3) in 15 (63%) patients. Two patients had extraocular Rb at diagnosis, and four of the patients who had intraocular Rb at diagnosis refused treatment and then came back with extraocular Rb. In total, extraocular disease was encountered in six eyes (six patients). After a 120-month median follow-up period, 24 patients (5%) died of second neoplasms (n = 3) or metastases (n = 21). Significant predictive factors for metastasis and death included advanced IIRC tumor stage (p < 0.0001), the presence of high-risk pathological features in the enucleated eyes (p = 0.013), parental refusal of the recommended primary treatment plan (p < 0.0001), and extraocular extension (p < 0.0001).

Conclusion

The 5-year survival rates of Rb patients in Jordan are as high as those in high-income countries. However, 5% are still dying from metastatic disease, prompting the need for awareness campaigns to educate the public about the high cure rates and to prevent treatment abandonment.

Special Issue of Cancers: "Retinoblastoma: Current Challenges and Promising New Approaches"

Despite being a rare pediatric cancer arising in the developing retina from red/green cone precursors, retinoblastoma is the most common eye cancer worldwide and occupies an emblematic position in oncology and human genetics for the following reasons:-Historically, the discovery of RB1 and the recessive nature of its mutations led to the prototypic description of anti-oncogenes or tumor suppressor genes [...].

Retinoblastoma: Review and new insights

Retinoblastoma (Rb), the most frequent malignant intraocular tumor in childhood, is caused by mutations in the retinoblastoma gene (RB1) situated on chromosome 13q14.2. The incidence of retinoblastoma is approximately 1 in 17,000 live births with approximately 8,000 new cases diagnosed each year worldwide. Rb is the prototypical hereditary cancer in humans. Autosomal dominant inheritance is seen in 30-40% of cases whereas the non-inherited sporadic type accounts for the remaining 60-70%. Rb arises due to inactivation of both alleles of the Rb tumor suppressor gene, which results in a defective Rb protein (pRB) with subsequent cell cycle impairment and uncontrolled cell proliferation. Patients with Rb have survival rates higher than 95-98% in industrialized countries but mortality remains high in developing countries. For example, the mortality rate in Africa is 70%. In all cases of intraocular and extraocular retinoblastoma, there is a need for new therapies that are more effective and carry less risk of toxicity. The Bruckner test is a practical and easy test for the detection of Rb, this test consists of assessing the fundus reflex through the pupil (red reflex) in both eyes simultaneously with a bright coaxial light produced with the direct ophthalmoscope. Rb can be detected by the Bruckner test showing a pupil that shines white or “Leukocoria”. Although the diagnosis of Rb remains essentially clinical, the newly identified biomarkers could contribute to early molecular detection, timely detection of micrometastases and establish new therapeutic options for Rb.

Metastatic Death Based on Presenting Features and Treatment for Advanced Intraocular Retinoblastoma: A Multicenter Registry-Based Study

PURPOSE

To evaluate presenting features, tumor size, and treatment methods for risk of metastatic death due to advanced intraocular retinoblastoma (RB).

DESIGN

International, multicenter, registry-based retrospective case series.

PARTICIPANTS

A total of 1841 patients with advanced RB.

METHODS

Advanced RB was defined by 8th edition American Joint Committee on Cancer (AJCC) categories cT2 and cT3 and new AJCC-Ophthalmic Oncology Task Force (OOTF) Size Groups (1: < 50% of globe volume, 2: > 50% but < 2/3, 3: > 2/3, and 4: diffuse infiltrating RB). Treatments were primary enucleation, systemic chemotherapy with secondary enucleation, and systemic chemotherapy with eye salvage.

MAIN OUTCOME MEASURES

Metastatic death.

RESULTS

The 5-year Kaplan-Meier cumulative survival estimates by patient-level AJCC clinical subcategories were 98% for cT2a, 96% for cT2b, 88% for cT3a, 95% for cT3b, 92% for cT3c, 84% for cT3d, and 75% for cT3e RB. Survival estimates by treatment modality were 96% for primary enucleation, 89% for systemic chemotherapy and secondary enucleation, and 90% for systemic chemotherapy with eye salvage. Risk of metastatic mortality increased with increasing cT subcategory (P < 0.001). Cox proportional hazards regression analysis confirmed a higher risk of metastatic mortality in categories cT3c (glaucoma, hazard ratio [HR], 4.9; P = 0.011), cT3d (intraocular hemorrhage, HR, 14.0; P < 0.001), and cT3e (orbital cellulitis, HR, 19.6; P < 0.001) than in category cT2a and with systemic chemotherapy with secondary enucleation (HR, 3.3; P < 0.001) and eye salvage (HR, 4.9; P < 0.001) than with primary enucleation. The 5-year Kaplan-Meier cumulative survival estimates by AJCC-OOTF Size Groups 1 to 4 were 99%, 96%, 94%, and 83%, respectively. Mortality from metastatic RB increased with increasing Size Group (P < 0.001). Cox proportional hazards regression analysis revealed that patients with Size Group 3 (HR, 10.0; P = 0.002) and 4 (HR, 41.1; P < 0.001) had a greater risk of metastatic mortality than Size Group 1.

CONCLUSIONS

The AJCC-RB cT2 and cT3 subcategories and size-based AJCC-OOTF Groups 3 (> 2/3 globe volume) and 4 (diffuse infiltrating RB) provided a robust stratification of clinical risk for metastatic death in advanced intraocular RB. Primary enucleation offered the highest survival rates for patients with advanced intraocular RB.

The Impact of Cell-Free DNA Analysis on the Management of Retinoblastoma

Retinoblastoma is a childhood eye cancer, mainly caused by mutations in the RB1 gene, which can be somatic or constitutional. Unlike many other cancers, tumour biopsies are not performed due to the risk of tumour dissemination. As a result, until recently, somatic genetic analysis was only possible if an affected eye was removed as part of a treatment. Several recent proof of principle studies have demonstrated that the analysis of tumour-derived cell-free DNA, either obtained from ocular fluid or blood plasma, has the potential to advance the diagnosis and influence the prognosis of retinoblastoma patients. It has been shown that a confirmed diagnosis is possible in retinoblastoma patients undergoing conservative treatment. In vivo genetic analysis of retinoblastoma tumours is also now possible, allowing the potential identification of secondary genetic events as prognostic biomarkers. In addition, noninvasive prenatal diagnosis in children at risk of inheriting retinoblastoma has been developed. Here, we review the current literature and discuss the potential impact of cell-free DNA analysis on both the diagnosis and treatment of retinoblastoma patients and their families.