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1.
Ophthalmic Epidemiol ; : 1-7, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578693

RESUMO

PURPOSE: To identify sociodemographic factors associated with the visual outcomes of retinoblastoma survivors. METHODS: Retrospective cohort study using a US-based clinical data registry. All individuals < 18 years of age with a history of retinoblastoma in the Intelligent Research in Sight (IRIS®) Registry (1/1/2013-12/31/2020). The primary outcome was visual acuity below the threshold for legal blindness (20/200 or worse) in at least one eye. Multivariable logistic regression was used to evaluate the association between visual outcomes and age, sex, laterality, race, ethnicity, type of insurance, and geographic location. RESULTS: This analysis included 1545 children with a history of retinoblastoma. The median length of follow-up was 4.1 years (IQR, 2.2-5.9 years) and the median age at most recent clinical visit was 12 years (IQR, 8-16 years). Retinoblastoma was unilateral in 54% of cases. Poor vision in at least one eye was identified in 78% of all children and poor vision in both eyes in 17% of those with bilateral disease. Poor visual outcomes were associated with unilateral diagnosis (OR, 1.55; 95% CI,1.13-2.12; p = .007), Black race (OR, 2.03; 95% CI, 1.19-3.47; p = .010), Hispanic ethnicity (OR, 1.65; 95% CI, 1.16-2.37; p = .006), and non-private insurance (OR, 1.47; 95% CI, 1.02-2.10; p = .037). CONCLUSIONS: Poor visual outcomes appear to be more common among Black, Hispanic, and publicly insured children with a history of retinoblastoma, raising concerns regarding healthcare inequities. Primary care physicians should ensure that young children receive red reflex testing during routine visits and consider retinoblastoma in the differential diagnosis of abnormal eye exams.

2.
Head Neck ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594829

RESUMO

BACKGROUND: Human papillomavirus (HPV) is an increasing risk factor for cancer. HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) is associated with a favorable outcome. Blockstaining for p16 is a surrogate marker for HPV+ OPSCC. In oral and laryngeal squamous cell carcinoma (OSCC/LSCC), the relevance of p16 immunohistochemistry, alone or in combination with other cell cycle-related proteins, to identify HPV-driven non-OPSCC is less well understood. METHODS: We stained for p16, pRb, cyclin D1, and p53 in 327 HNSCC. In 310 OPSCC, HPV-status was assessed by HPV DNA PCR. In 119 non-OPSCC, RNA in situ hybridization was additionally performed. HPV-status was correlated with staining patterns, p53 and clinical data. RESULTS: The OPSCC showed blockstaining for p16 in 36%, 8% were equivocal. Of these, HPV-testing was performed in 57%, and 53% were positive for HPV DNA. HPV-association correlated with absence of pRb and cyclin D1 and favorable outcome. In non-OPSCC, 18% showed p16-blockstaining, and 13% showed E6/E7 RNA. Six of seven HPV+ OSCC and 8/8 LSCC lost pRb and cyclin D1. Compared to HPV-negative counterparts, patients with HPV+ cancers had lower rates of alcohol consumption and keratinizing morphology. HPV-positive OSCC had a longer overall survival (p < 0.05). HPV subtype 16 was the most common. CONCLUSIONS: We conclude that HPV-positive non-OPSCC are associated with p16 overexpression and low levels of pRb and cyclin D1. High expression of pRb and cyclin D1 indicates HPV-negativity.

3.
Pediatr Blood Cancer ; : e30987, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594882

RESUMO

Retinoblastoma, the most common intraocular tumor in childhood, still faces challenges in diagnosis and treatment, particularly in low- and middle-income countries. Identifying strategies to improve the time to diagnosis and access to treatment is crucial to enhance survival rates and preserve ocular health. We conducted a systematic review to identify interventions that have demonstrated potential in addressing these challenges. We performed a comprehensive search across databases until March 2023. Out of the studies reviewed, 21 met the inclusion criteria and were categorized into five main areas: surveillance strategies, genetic counseling, education, public assistance, and international partnership. Despite the obstacles faced, the initiatives identified in this review present acts toward improving the time to diagnosis and access to treatment for retinoblastoma. Based on the extracted data, we propose a comprehensive chain of initiatives. We firmly believe that implementing this chain of initiatives can lead to improved clinical outcomes for retinoblastoma patients.

4.
J Clin Med ; 13(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38610910

RESUMO

Background: This study compares the outcomes of managing retinoblastoma between patients with unilateral and bilateral presentations. Methods: The study, conducted at the King Hussein Cancer Center in Amman, Jordan, retrospectively analyzed cases of retinoblastoma treated between March 2003 and December 2019. Evaluation criteria included clinical features, disease stage, treatment methods, and overall management outcomes. Results: The study comprised 697 eyes from 478 patients with retinoblastoma, with 52% being males. Bilateral disease was observed in 70% of patients, and a family history of retinoblastoma was more prevalent in cases with bilateral disease (20%) compared to those with unilateral disease (4%). Unilateral cases had a median age at diagnosis of 28 months, whereas bilateral cases were diagnosed at a median age of 6 months. Extra-ocular retinoblastoma was detected in 1% of eyes. According to the International Intraocular Retinoblastoma Classification (IIRC), 88% of unilateral cases presented with advanced disease (IIRC group D/E), compared to 46% in bilateral cases. Primary enucleation was performed in 29% of unilateral cases and 16% of bilateral cases (p-value 0.0007). Eye salvage rates were 31% in unilateral cases and 68% in bilateral cases (p-value < 0.0001). At 120 months of follow-up, 5% of patients died from secondary neoplasms or metastases, 81% were alive, and 14% were lost to follow-up. There was no significant difference in metastasis, secondary neoplasms, or mortality between patients with unilateral and bilateral retinoblastoma. Conclusions: This study highlights the nuanced differences in clinical characteristics and outcomes between unilateral and bilateral retinoblastoma, emphasizing the necessity of customized management and early detection strategies. It demonstrates that while bilateral retinoblastoma benefits from earlier detection and has a higher rate of eye salvage, there is no significant difference in metastasis or mortality rates when compared to unilateral cases. The critical roles of primary enucleation in advanced cases, along with effective communication and patient education, are also underscored to improve treatment adherence. Overall, these findings point to the importance of tailored approaches in optimizing outcomes for the diverse patient population affected by retinoblastoma.

5.
Front Oncol ; 14: 1372548, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606112

RESUMO

Introduction: This systematic review and meta-analysis aimed to examine the risk of second primary cancers (SPCs) among retinoblastoma (Rb) patients, both hereditary and nonhereditary. Previous studies have reported on the long-term risk of SPCs in these patient populations, but a comprehensive synthesis of the existing evidence is lacking. Methods: A systematic search was conducted in PubMed, EMBASE, and Cochrane Library from inception to 12 March 2023, supplemented by manual screening. Eligible studies were identified, and data were extracted. The primary outcome measure was the standardized incidence ratios (SIRs) of SPCs in Rb patients. Summary estimates were calculated using random or fixed effects models. The quality of included studies was assessed using the Newcastle-Ottawa Scale. Results: Ten studies, including nine high-quality studies, were included in this review. The summary estimate of SIR for SPCs among hereditary Rb patients was 17.55 (95% CI=13.10-23.51), while the pooled estimate of SIR for SPCs among nonhereditary Rb patients was 1.36 (95% CI=0.90-2.04). Significant differences in SIRs for different SPC types were observed (P=0.028), including nasal cavity tumor (SIR=591.06, 95% CI=162.79-2146.01), bone tumor (SIR=442.91, 95% CI=191.63-1023.68), soft tissue sarcoma (SIR=202.93, 95% CI=114.10-360.93), CNS (SIR=12.84, 95% CI=8.80-18.74), and female breast cancer (SIR=3.68, 95% CI=2.52-5.37). Chemotherapy and radiation therapy were associated with an increased risk of SPCs among hereditary Rb patients. Discussion: The findings of this review indicate that hereditary Rb patients have a significantly elevated risk of developing SPCs, whereas nonhereditary Rb patients do not show the same risk. Furthermore, significant differences were observed in the SIRs of different SPC types. Treatment techniques, specifically chemotherapy and radiation therapy, were associated with an increased risk of SPCs among hereditary Rb patients. These findings highlight the importance of radiation protection for Rb patients and the need for further research and tailored management strategies for this high-risk population.

6.
Indian J Pediatr ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639859

RESUMO

Retinoblastoma (RB) is the most common intraocular malignancy of childhood. Advanced stage presentation of RB is common in low middle-income countries (LMICs) due to lack of awareness, social taboos associated with enucleation, seeking alternative conservative treatment options, and poor accessibility to health care. Over the last few decades, there have been significant advancements in the management of extraocular RB (EORB) which have improved outcomes and helped in minimizing treatment-related toxicities. The incorporation of multimodality approaches including chemotherapy, surgery, and radiotherapy (RT) has shown promising results; however, prognosis remains poor especially in LMICs. In this article, authors have discussed the ICMR consensus guidelines on the management of EORB, including metastatic RB.

7.
Am J Ophthalmol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615831

RESUMO

PURPOSE: To evaluate changes in retinal microvascular density and choroidal vascularity in patients with retinoblastoma (RB) after intra-arterial chemotherapy (IAC). DESIGN: Retrospective clinical cohort study. METHODS: This study included 12 unilateral RB eyes treated with IAC (RB tumour), 12 contralateral normal eyes (RB fellow), and 12 healthy controls. The macular retinal thickness and retinal microvascular structure, including foveal avascular zone (FAZ) area, the macular and peripapillary superficial vessel density (SVD) and deep vessel density (DVD), were measured by optical coherence tomography angiography (OCTA). The choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA) and Choroidal Vascularity Index (CVI), were measured by spectral-domain optical coherence tomography (SD-OCT). A comparison among the three groups was conducted, while the correlations among the parameters were analyzed. RESULTS: Between the three cohorts, the foveal retinal thickness, the SVD, DVD, ChT, TCA, LA, SA and CVI were significantly lower in RB tumour compared to RB fellow and the control eyes (all P<0.01). There were no significant differences in the parameters between the contralateral and control eyes. The correlation analyses indicated a significant negative correlation between the total melphalan dose and foveal and parafoveal DVD, ChT, and LA. CONCLUSIONS: The retinal microvascular density and choroidal vascularity were lower in unilateral RB treated with IAC, and seemed to be related to the total melphalan dose. Moreover there were no measurable changes in the contralateral eyes.

8.
Asia Pac J Ophthalmol (Phila) ; : 100058, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615905

RESUMO

Retinoblastoma, the primary ocular malignancy in pediatric patients, poses a substantial threat to mortality without prompt and effective management. The prognosis for survival and preservation of visual acuity hinges upon the disease severity at the time of initial diagnosis. Notably, retinoblastoma has played a crucial role in unraveling the genetic foundations of oncogenesis. The process of tumorigenesis commonly begins with the occurrence of biallelic mutation in the RB1 tumor suppressor gene, which is then followed by a cascade of genetic and epigenetic alterations that correspond to the clinical stage and pathological features of the tumor. The RB1 gene, recognized as a tumor suppressor, encodes the retinoblastoma protein, which plays a vital role in governing cellular replication through interactions with E2F transcription factors and chromatin remodeling proteins. The diagnosis and treatment of retinoblastoma necessitate consideration of numerous factors, including disease staging, germline mutation status, family psychosocial factors, and the resources available within the institution. This review has systematically compiled and categorized the latest developments in the diagnosis and treatment of retinoblastoma which enhanced the quality of care for this pediatric malignancy.

9.
Indian J Pediatr ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38609685

RESUMO

Retinoblastoma (RB) is the most common childhood intraocular malignancy. Delayed presentation due to a lack of awareness and advanced intraocular tumors are a common scenario in low-middle income countries (LMICs). Remarkable treatment advances have been made in the past few decades allowing globe salvage in advanced intraocular RB (IORB) including systemic chemotherapy with focal consolidation and targeted treatments like intraarterial chemotherapy and intravitreal chemotherapy. However, a lack of availability and affordability limits the use of such advances in LMICs. External beam radiotherapy, despite risk of second cancers in RB with germline mutations, still remains useful for recalcitrant RB not responding to any other treatment. When choosing conservative treatment for advanced IORB, the cost and long duration of treatment, morbidity from multiple evaluation under anesthesias (EUAs), side effects of treatment and risk of treatment failure need to be taken into account and discussed with the parents. In this article, the authors discuss the ICMR consensus guidelines on the management of IORB.

10.
Asia Pac J Ophthalmol (Phila) ; : 100061, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38641204

RESUMO

Retinoblastoma stands as a paradigm of success in treating malignancies among pediatric patients. Over recent decades, the approach to managing retinoblastoma has evolved significantly, transitioning from the preservation of patients' lives to the preservation of eyes and vision while minimizing treatment-related complications. Chemotherapy, administered through diverse routes, has solidified its role as the cornerstone of retinoblastoma treatment. In addition to intravenous chemotherapy (IVC), alternative administration routes, including intraarterial (IAC), intravitreal, intracameral, and periocular delivery, have emerged as promising modalities for retinoblastoma management. Numerous studies have demonstrated outstanding outcomes, achieving nearly 100% salvage rates for eyes classified under groups A-C. However, for advanced intraocular retinoblastoma (groups D and E eyes), IAC appears to offer superior local control rates compared to IVC. Intravitreal injection of chemotherapeutic agents, when administered in a controlled and secure manner, holds promise in averting the need for enucleation and radiotherapy in advanced retinoblastoma cases presenting with vitreous seeds. The optimal chemotherapy strategy remains meticulously tailored based on numerous factors. This review provides a comprehensive update on chemotherapy across various routes, encompassing key considerations, dosages, administration methods, treatment outcomes, and potential complications. Furthermore, it explores emerging potential treatments and outlines future directions aimed at enhancing treatment outcomes.

11.
Heliyon ; 10(6): e27653, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38524558

RESUMO

Objective: To explore the role and mechanisms of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in angiogenesis of retinoblastoma (RB) cells. Methods: This study investigated the roles of NEAT1 in RB progression. The RNA expression levels of NEAT1, miR-106a, and hypoxia-inducible factor-1alpha (HIF-1α) examined by quantitative reverse transcription polymerase chain reaction (RT-qPCR) were compared between RB cells and normal retinal pigment epithelial (RPE) cells. The binding sites between NEAT1 and miR-106a, and between miR-106a and HIF-1α were predicted by the TargetScan database and verified using the dual-luciferase reporter assay. By transfection of overexpression plasmid or shRNA of NEAT1, and/or treatment of miR-106a inhibitor or mimics, proliferation, invasion, and angiogenesis of RB cells (measured by the MTT assay, the Transwell assay, and the tube formation assay, respectively) were compared between groups. Group comparisons were analyzed using one-way analysis of variance (ANOVA), and Tukey's post-hoc test was employed for further statistical assessment. P-value less than 0.05 was considered statistically significant. Results: The RNA expression levels of NEAT1 and HIF-1α were upregulated in RB cells, whereas the expression level of miR-106a was downregulated compared with RPE cells. NEAT1 overexpression or miR-106a knockdown advanced proliferation, invasion, and tube formation of RB cells. As a target of NEAT1, miR-106a could sponge HIF-1α to downregulate HIF-1α expression level. Functional analyses indicated that miR-106a knockdown reversed the inhibitory effects of NEAT1 silencing on the proliferation, invasion, and tube formation of RB cells. Furthermore, miR-106a overexpression suppressed RB cell angiogenesis by downregulating HIF-1α expression level. Conclusion: NEAT1 promoted proliferation, invasion, and angiogenesis of RB cells through upregulation of HIF-1α expression level by sponging miR-106a, demonstrating that NEAT1 may be a novel target for RB treatment.

12.
Cesk Slov Oftalmol ; 80(Ahead of print): 1001-1007, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38538290

RESUMO

Retinoblastoma is the most common primary malignant intraocular tumor in children. Seeding, specifically the dispersion of the tumor into the adjacent compartments, represents a major parameter determining the degree of retinoblastoma according to the International Classification of Retinoblastoma. In this article we focused on vitreous seeding, one of the main limiting factors in the successful "eye preservation treatment" of retinoblastoma. This article presents an overview of the history of vitreous seeding of retinoblastoma, established treatment procedures and new-research modalities. The introduction of systemic chemotherapy in the treatment of retinoblastoma at the end of the 1990s represented a significant breakthrough, which enabled the progressive abandonment of radiotherapy with its attendant side effects. However, the attained concentrations of chemotherapeutics in the vitreous space during systemic chemotherapy are not sufficient for the treatment of vitreous seeding, and the toxic effects of systemic chemotherapy are not negligible. A significant change came with the advent of chemotherapy in situ, with the targeted administration of chemotherapeutic drugs, namely intra-arterial and intravitreal injections, contributing to the definitive eradication of external radiotherapy and a reduction of systemic chemotherapy. Although vitreous seeding remains the most common reason for the failure of intra-arterial chemotherapy, this technique has significantly influenced the original treatment regimen of children with retinoblastoma. However, intravitreal chemotherapy has made the greatest contribution to increasing the probability of preservation of the eyeball and visual functions in patients with advanced findings. Novel local drug delivery modalities, gene therapy, oncolytic viruses and immunotherapy from several ongoing preclinical and clinical trials may represent promising approaches in the treatment of vitreous retinoblastoma seeding, though no clinical trials have yet been completed for routine use.


Assuntos
Neoplasias da Retina , Retinoblastoma , Criança , Humanos , Retinoblastoma/induzido quimicamente , Retinoblastoma/tratamento farmacológico , Neoplasias da Retina/induzido quimicamente , Neoplasias da Retina/tratamento farmacológico , Melfalan/efeitos adversos , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Corpo Vítreo/patologia , Injeções Intravítreas , Estudos Retrospectivos
13.
Int Ophthalmol ; 44(1): 133, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38480634

RESUMO

PURPOSE: To investigate the expression of nuclear receptor subfamily 1 group D member 1 (NR1D1) and nuclear receptor subfamily 2 group E Member 3 (NR2E3) in retinoblastoma (RB) and their correlation with the clinical and pathological features of RB. METHODS: Immunohistochemical (IHC) assays were performed to detect and evaluate the expression levels of NR1D1 and NR2E3 in paraffin-embedded tissue samples. The relationship between the expression levels and clinicopathological characteristics of RB patients was analyzed using the χ2 test or Fisher exact test. RESULTS: A total of 51 RB patients were involved in this research. The expression levels of NR1D1 (P = 0.004) and NR2E3 (P = 0.024) were significantly lower in RB tumor tissues than in normal retina. The expression levels of NR1D1 and NR2E3 were less positive in RB patients with advanced stages (P = 0.007, P = 0.015), choroidal infiltration (P = 0.003, P = 0.029), and optic nerve infiltration (P = 0.036, P = 0.003). In addition, a low expression level of NR2E3 was associated with high-risk pathology (P = 0.025) and necrosis (P = 0.035) of RB tissues. CONCLUSION: The expression levels of NR1D1 and NR2E3 were decreased in RB and closely associated with the clinical stage and high invasion of the disease. These findings provide new insights into the mechanism of RB progression and suggest that NR1D1 and NR2E3 could be potential targets for treatment strategies.


Assuntos
Neoplasias da Retina , Retinoblastoma , Humanos , Retinoblastoma/patologia , Neoplasias da Retina/diagnóstico , Receptores Nucleares Órfãos , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares
14.
BMC Ophthalmol ; 24(1): 114, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481156

RESUMO

PURPOSE: To report the result of strabismus surgery in eye-salvaged retinoblastoma (Rb) patients. METHODS: A retrospective case series including 18 patients with Rb and strabismus who underwent strabismus surgery after completing tumor treatment by a single pediatric ophthalmologist. RESULTS: A total of 18 patients (10 females and 8 males) were included with a mean age of 13.3 ± 3.0 (range, 2-39) months at the time tumor presentation and 6.0 ± 1.5 (range, 4-9) years at the time of strabismus surgery. Ten (56%) patients had unilateral and 8(44%) had bilateral involvement and the most common worse eye tumor's group was D (n = 11), C (n = 4), B (n = 2) and E (n = 1). Macula was involved by the tumors in 12 (67%) patients. The tumors were managed by intravenous chemotherapy (n = 8, 47%), intra-arterial chemotherapy (n = 7, 41%) and both (n = 3, 17%). After complete treatment, the average time to strabismus surgery was 29.9 ± 20.5 (range, 12-84) months. Except for one, visual acuity was equal or less than 1.0 logMAR (≤ 20/200) in the affected eye. Seven (39%) patients had exotropia, 11(61%) had esotropia (P = 0.346) and vertical deviation was found in 8 (48%) cases. The angle of deviation was 42.0 ± 10.4 (range, 30-60) prism diopter (PD) for esotropic and 35.7 ± 7.9 (range, 25-50) PD for exotropic patients (P = 0.32) that after surgery significantly decreased to 8.5 ± 5.3 PD in esotropic cases and 5.9 ± 6.7 PD in exotropic cases (P < 0.001). The mean follow-up after surgery was 15.2 ± 2.0 (range, 10-24) months, in which, 3 (17%) patients needed a second surgery. CONCLUSION: Strabismus surgery in treated Rb is safe and results of the surgeries are acceptable and close to the general population. There was not associated with tumor recurrence or metastasis.


Assuntos
Esotropia , Exotropia , Neoplasias da Retina , Retinoblastoma , Estrabismo , Masculino , Feminino , Humanos , Criança , Adolescente , Retinoblastoma/cirurgia , Retinoblastoma/complicações , Estudos Retrospectivos , Seguimentos , Recidiva Local de Neoplasia , Estrabismo/cirurgia , Esotropia/cirurgia , Músculos Oculomotores/cirurgia , Exotropia/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Neoplasias da Retina/cirurgia , Neoplasias da Retina/complicações , Resultado do Tratamento
15.
Indian J Pediatr ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38492167

RESUMO

Retinoblastoma (RB) is the most common intraocular tumor in childhood. It is mainly caused by mutations in both alleles of the RB1 tumor suppressor gene that is found on chromosome 13 and regulates the cell cycle. Approximately 8000 children are diagnosed with RB globally each year, with an estimated 1500 cases occurring in India. The survival rate of RB has improved to more than 90% in the developed world. Leukocoria and proptosis are the most common presenting features of RB in Asian Indian populations. Most cases of RB are diagnosed by fundus examination followed by ultrasound. The International Classification of Retinoblastoma is the most used scheme for the staging and classification of intraocular RB in India. Prenatal testing and preimplantation genetic testing for RB may be beneficial in high-risk families. Histopathologic risk factors such as massive choroidal invasion and post-laminar optic nerve help in predicting the occurrence of metastasis in children with RB, while presence of microscopic residual disease requires aggressive adjuvant treatment in eyes enucleated for group E RB. The review provides a consensus document on diagnosis and genetics of RB in India.

16.
Plant Commun ; : 100857, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38433446

RESUMO

The transition from mitosis to meiosis is a critical event in the reproductive development of all sexually reproducing species. However, the mechanisms that regulate this process in plants remain largely unknown. Here, we find that the rice (Oryza sativa L.) protein RETINOBLASTOMA RELATED 1 (RBR1) is essential to the transition from mitosis to meiosis. Loss of RBR1 function results in hyper-proliferative sporogenous-cell-like cells (SCLs) in the anther locules during early stages of reproductive development. These hyper-proliferative SCLs are unable to initiate meiosis, eventually stagnating and degrading at late developmental stages to form pollen-free anthers. These results suggest that RBR1 acts as a gatekeeper of entry into meiosis. Furthermore, cytokinin content is significantly increased in rbr1 mutants, whereas the expression of type-B response factors, particularly LEPTO1, is significantly reduced. Given the known close association of cytokinins with cell proliferation, these findings imply that hyper-proliferative germ cells in the anther locules may be attributed to elevated cytokinin concentrations and disruptions in the cytokinin pathway. Using a genetic strategy, the association between germ cell hyper-proliferation and disturbed cytokinin signaling in rbr1 has been confirmed. In summary, we reveal a unique role of RBR1 in the initiation of meiosis; our results clearly demonstrate that the RBR1 regulatory module is connected to the cytokinin signaling pathway and switches mitosis to meiosis in rice.

17.
Cardiovasc Intervent Radiol ; 47(4): 407-415, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38509339

RESUMO

Retinoblastoma is the most common eye malignancy in children that if left untreated can invade intraocular structures, metastasize, and rarely lead to death. Traditionally treated with systemic chemotherapy, Intra-arterial chemotherapy is gaining popularity as it allows for the direct administration of chemotherapy through the ophthalmic artery, thus reducing systemic side effects. Intra-arterial chemotherapy procedures have evolved, with refinements to reduce risks and radiation exposure. Intra-arterial chemotherapy boasts an impressive technical success rate and one year ocular survival even amongst advanced cases. This review offers a thorough examination of the technique, indications, contraindications, outcomes, and alternative options for Intra-arterial chemotherapy.


Assuntos
Exposição à Radiação , Neoplasias da Retina , Retinoblastoma , Criança , Humanos , Lactente , Retinoblastoma/induzido quimicamente , Retinoblastoma/tratamento farmacológico , Neoplasias da Retina/induzido quimicamente , Neoplasias da Retina/tratamento farmacológico , Infusões Intra-Arteriais , Artéria Oftálmica/patologia , Melfalan/uso terapêutico , Estudos Retrospectivos
18.
Biomed Pharmacother ; 174: 116437, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38522240

RESUMO

Retinoblastoma (RB) is a type of pediatric solid tumor in the fundus. The lack of precision therapies combined with the difficulty of delivering small interfering RNA (siRNA) into the eyes means that there is currently no nucleic acid-based therapy for RB in clinical practice. Here, we reported on anti-GD2 and glutathione-responsive spherical nucleic acids (SNAs), loaded with siRNA and the inhibitor NVP-CGM097, which jointly blocked the oncogenic factor n in RB cells (Y79 and WERI-RB-1). The SNAs were formed through the self-assembly of bifunctional cholesterol amphiphiles containing aptamers that specifically targeted GD2-positive RB cells, allowing for the formation of an SNA with a dense DNA shell. The aptamer/siRNA component functioned both as a carrier and a payload, enhancing the specific recognition and delivery of both components and constituting an active agent for MDM2 regulation. Following SNA endocytosis by RB cells, siRNA and NVP-CGM097 were released from the SNA particles by glutathione, which synergistically blocked the MDM2-p53 pathway, increasing p53 protein content and inducing cell apoptosis. This study showed a potent antitumor effect following intravitreal injection of SNAs in Y79 tumor-bearing mice through clinical manifestation and tumor pathological analysis. In hematological analysis and hepatotoxicity assays, SNAs were safer for mice than melphalan, the favored drug for treating RB in clinical practice. Our results illustrated the potential of intravitreally injected SNAs as a precision medicine for treating RB.

19.
Biomed Pharmacother ; 173: 116403, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490156

RESUMO

Drug resistance (DR) is one of the challenges in treating retinoblastoma (Rb) that warrants novel approaches. With the emerging evidence on the role of small extracellular vesicles (sEVs) as a drug-delivery carrier system, in this study, we derived the drug-resistant (DR) clones of Y79 cells and evaluated the efficacy of sEVs-loaded with carboplatin (sEVs-CPT) to reverse the chemoresistance. Drug-resistant clones of Y79 cells (DR-Y79) were systematically developed through sequential exposure to carboplatin (CPT), showcasing a sixfold increase in inhibitory concentration when compared to parental Y79 cells (IC50: 41.4 µg/mL and 6.2 µg/mL) (P<0.0001). These DR-Y79 cells show higher expression of ABCG2 and higher expression of DR genes than parental Y79 cells (P<0.0001). The sEVs were isolated from the conditioned media of Y79 cells using ultracentrifugation (UC) and characterized. Further, the sEVs were loaded with CPT and achieved higher encapsulation efficiency at one hour, and drug release of sEVs-CPT was highest at ∼80% at pH 5.0. The cytotoxicity of sEVs-CPT on Y79 cells and DR-Y79 was higher when compared to the CPT (IC50: 3.5 µg/mL vs 6.2 µg/mL; 23.1 µg/mL vs 41.2 µg/mL) (p<0.0001). This study demonstrates that sequential exposure to CPT generates DR clones of Y79 cells, which could serve as an appropriate model to evaluate the efficacy of drugs. The sEVs-CPT were highly effective in enhancing cytotoxicity in DR-Y79 cells, and appear to hold promise as a novel complimentary drug delivery system.


Assuntos
Vesículas Extracelulares , Neoplasias da Retina , Humanos , Carboplatina/farmacologia , Preparações Farmacêuticas , Linhagem Celular Tumoral
20.
Surv Ophthalmol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492584

RESUMO

Artificial Intelligence (AI) has become a focus of research in the rapidly evolving field of ophthalmology. Nevertheless, there is a lack of systematic studies on the health economics of AI in this field. We examine studies from the PubMed, Google Scholar, and Web of Science databases that employed quantitative analysis, retrieved up to July 2023. Most of the studies indicate that AI leads to cost savings and improved efficiency in ophthalmology. On the other hand, some studies suggest that using AI in healthcare may raise costs for patients, especially when taking into account factors such as labor costs, infrastructure, and patient adherence. Future research should cover a wider range of ophthalmic diseases beyond common eye conditions. Moreover, conducting extensive health economic research, designed to collect data relevant to its own context, is imperative.

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