-
Investigative Ophthalmology & Visual... Dec 2023Although there have been improvements in the management of metastatic retinoblastoma, most patients do not survive, and all patients suffer from multiple short- and...
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.
Topics: Animals; Humans; Retinoblastoma; Neoplasm Recurrence, Local; Cell Line; Disease Models, Animal; Retinal Neoplasms
PubMed: 38117242
DOI: 10.1167/iovs.64.15.27 -
Seminars in Cancer Biology Jan 2024CDK4, along with its regulatory subunit, cyclin D, drives the transition from G1 to S phase, during which DNA replication and metabolic activation occur. In this... (Review)
Review
CDK4, along with its regulatory subunit, cyclin D, drives the transition from G1 to S phase, during which DNA replication and metabolic activation occur. In this canonical pathway, CDK4 is essentially a transcriptional regulator that acts through phosphorylation of retinoblastoma protein (RB) and subsequent activation of the transcription factor E2F, ultimately triggering the expression of genes involved in DNA synthesis and cell cycle progression to S phase. In this review, we focus on the newly reported functions of CDK4, which go beyond direct regulation of the cell cycle. In particular, we describe the extranuclear roles of CDK4, including its roles in the regulation of metabolism, cell fate, cell dynamics and the tumor microenvironment. We describe direct phosphorylation targets of CDK4 and decipher how CDK4 influences these physiological processes in the context of cancer.
Topics: Humans; Cyclins; Cyclin-Dependent Kinase 4; Cyclin D; Phosphorylation; Cell Cycle; Neoplasms; Cell Cycle Proteins; Tumor Microenvironment
PubMed: 38135020
DOI: 10.1016/j.semcancer.2023.12.002 -
Child's Nervous System : ChNS :... Sep 2023Pineal parenchymal tumors in children are rare. They consist of two main types, pineoblastoma (PB) and pineal parenchymal tumor of intermediate differentiation (PPTID),... (Review)
Review
Pineal parenchymal tumors in children are rare. They consist of two main types, pineoblastoma (PB) and pineal parenchymal tumor of intermediate differentiation (PPTID), which are World Health Organization (WHO) grade 4 and grade 2-3 respectively. PBs are divided into four distinct molecular groups: PB-miRNA1, PB-miRNA2, PB-RB1, and PB-MYC/FOXR2. PB-RB1 and PB-MYC/FOXR2 affect young children and are associated with a dismal prognosis. PB-miRNA1 and PB-miRNA2 groups affect older children and follow a more favorable course. They are characterized by mutually exclusive alterations in genes involved in miRNA biogenesis, including DICER1, DROSHA, and DGCR8. They may be sporadic or may represent one manifestation of DICER1 syndrome. PB-RB1 tumors show alterations in the RB1 gene and may develop in the setting of congenital retinoblastoma, a condition known as "trilateral retinoblastoma." In the pediatric population, PPTIDs typically affect adolescents. They are characterized by small in-frame insertions in the KBTBD4 gene which is involved in ubiquitination.
Topics: Adolescent; Humans; Child; Child, Preschool; Pinealoma; Brain Neoplasms; Pineal Gland; Pathology, Molecular; Retinoblastoma; MicroRNAs; RNA-Binding Proteins; Retinal Neoplasms; Ribonuclease III; DEAD-box RNA Helicases; Forkhead Transcription Factors
PubMed: 35972537
DOI: 10.1007/s00381-022-05637-x -
Critical Reviews in Oncology/hematology Feb 2024Cervical cancer (CaCx) is the deadliest malignancy among women which is caused by human papillomavirus (HPV) and anthro-demographical/clinicopathological factors. HPV... (Review)
Review
Cervical cancer (CaCx) is the deadliest malignancy among women which is caused by human papillomavirus (HPV) and anthro-demographical/clinicopathological factors. HPV oncoproteins E6 and E7 target p53 and RB (retinoblastoma) protein degradation, Ataxia telangiectasia mutated (ATM), ATM-RAD3-related (ATR) inactivation and subsequent impairment of non-homologous end joining (NHEJ), homologous recombination, and base excision repair pathways. There is also an accumulation of genetic and epigenetic alterations in Tumor Growth Suppressors (TGS), oncogenes, and DNA repair genes leading to increased genome instability and CaCx development. These alterations might be responsible for differential clinical response to Cisplatin-based chemoradiotherapy (CRT) in patients. This review explores HPV-mediated DNA damage as a risk factor in CaCx development, the mechanistic role of genetic and epigenetic alterations in DNA repair genes and their association with CRT and outcome, It also explores new possibilities for the development of genetic and epigenetic-based biomarkers for diagnostic, prognostic, and molecular therapeutic interventions.
Topics: Humans; Female; Uterine Cervical Neoplasms; Oncogene Proteins, Viral; Papillomavirus E7 Proteins; Papillomavirus Infections; DNA; DNA Repair; Epigenesis, Genetic; Treatment Outcome
PubMed: 38122918
DOI: 10.1016/j.critrevonc.2023.104240 -
Indian Journal of Pediatrics Apr 2024Retinoblastoma (RB) is the most common childhood intraocular malignancy. Delayed presentation due to a lack of awareness and advanced intraocular tumors are a common... (Review)
Review
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.
PubMed: 38609685
DOI: 10.1007/s12098-024-05095-0 -
Advances in Protein Chemistry and... 2024Osteosarcoma is a malignant osseous neoplasm. Osteosarcoma is a primary bone malignancy capable of producing osteoid tissue or immature bones. A subsequent malignant... (Review)
Review
Osteosarcoma is a malignant osseous neoplasm. Osteosarcoma is a primary bone malignancy capable of producing osteoid tissue or immature bones. A subsequent malignant degeneration of the primary bone pathology occurs less frequently in adults. The over-expression of several proteins, including Heat shock proteins, Cofilin, Annexins, Insulin-like growth factor, transforming growth factor-β, Receptor tyrosine kinase, Ezrin, Runx2, SATB2, ATF4, Annexins, cofilin, EGFR, VEGF, retinoblastoma 1 (Rb1) and secreted protein, has been associated to the development and progression of osteosarcoma. These proteins are involved in cell adhesion, migration, invasion, and the control of cell cycle and apoptosis. In genomic studies, osteosarcoma has been associated with several genetic abnormalities, including chromosomal rearrangements, gene mutations, and gene amplifications. These differentially expressed proteins could be used as early identification biomarkers or treatment targets. Proteomics and genomics play significant parts in enhancing our molecular understanding of osteosarcoma, and their integration provides essential insights into this aggressive bone cancer. This review will discuss the tumour biology that has assisted in helping us better understand the causes of osteosarcoma and how they could potentially be used to find new treatment targets and enhance the survival rate for osteosarcoma patients.
Topics: Adult; Humans; Proteomics; Osteosarcoma; Genomics; Bone Neoplasms; Actin Depolymerizing Factors; Annexins
PubMed: 38220428
DOI: 10.1016/bs.apcsb.2023.06.001 -
Cell Reports Aug 2023The neddylation inhibitor MLN4924/Pevonedistat is in clinical trials for multiple cancers. Efficacy is generally attributed to cullin RING ligase (CRL) inhibition, but...
The neddylation inhibitor MLN4924/Pevonedistat is in clinical trials for multiple cancers. Efficacy is generally attributed to cullin RING ligase (CRL) inhibition, but the contribution of non-CRL targets is unknown. Here, CRISPR screens map MLN4924-monotherapy sensitivity in retinoblastoma to a classic DNA damage-induced p53/E2F3/BAX-dependent death effector network, which synergizes with Nutlin3a or Navitoclax. In monotherapy-resistant cells, MLN4924 plus standard-of-care topotecan overcomes resistance, but reduces DNA damage, instead harnessing ribosomal protein nucleolar-expulsion to engage an RPL11/p21/MYCN/E2F3/p53/BAX synergy network that exhibits extensive cross-regulation. Strikingly, unneddylatable RPL11 substitutes for MLN4924 to perturb nucleolar function and enhance topotecan efficacy. Orthotopic tumors exhibit complete responses while preserving visual function. Moreover, MLN4924 plus melphalan deploy this DNA damage-independent strategy to synergistically kill multiple myeloma cells. Thus, MLN4924 synergizes with standard-of-care drugs to unlock a nucleolar death effector network across cancer types implying broad therapeutic relevance.
Topics: Topotecan; Tumor Suppressor Protein p53; bcl-2-Associated X Protein; Cell Line, Tumor; Cyclopentanes; Ribosomal Proteins; Apoptosis; NEDD8 Protein
PubMed: 37552601
DOI: 10.1016/j.celrep.2023.112925 -
Pharmacology & Therapeutics Aug 2023Ocular cancers represent a rare pathology. The American Cancer Society estimates that 3,360 cases of ocular cancer occur annually in the United States. The major types... (Review)
Review
Ocular cancers represent a rare pathology. The American Cancer Society estimates that 3,360 cases of ocular cancer occur annually in the United States. The major types of cancers of the eye include ocular melanoma (also known as uveal melanoma), ocular lymphoma, retinoblastoma, and squamous cell carcinoma. While uveal melanoma is one of the primary intraocular cancers with the highest occurrence in adults, retinoblastoma remains the most common primary intraocular cancer in children, and squamous cell carcinoma presents as the most common conjunctival cancer. The pathophysiology of these diseases involves specific cell signaling pathways. Oncogene mutations, tumor suppressor mutations, chromosome deletions/translocations and altered proteins are all described as causal events in developing ocular cancer. Without proper identification and treatment of these cancers, vision loss, cancer spread, and even death can occur. The current treatments for these cancers involve enucleation, radiation, excision, laser treatment, cryotherapy, immunotherapy, and chemotherapy. These treatments present a significant burden to the patient that includes a possible loss of vision and a myriad of side effects. Therefore, alternatives to traditional therapy are urgently needed. Intercepting the signaling pathways for these cancers with the use of naturally occurring phytochemicals could be a way to relieve both cancer burden and perhaps even prevent cancer occurrence. This research aims to present a comprehensive review of the signaling pathways involved in various ocular cancers, discuss current therapeutic options, and examine the potential of bioactive phytocompounds in the prevention and targeted treatment of ocular neoplasms. The current limitations, challenges, pitfalls, and future research directions are also discussed.
Topics: Adult; Child; Humans; Retinoblastoma; Eye Neoplasms; Signal Transduction; Carcinoma, Squamous Cell; Retinal Neoplasms
PubMed: 37330112
DOI: 10.1016/j.pharmthera.2023.108479 -
Asia-Pacific Journal of Ophthalmology... 2024Retinoblastoma, the primary ocular malignancy in pediatric patients, poses a substantial threat to mortality without prompt and effective management. The prognosis for... (Review)
Review
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.
Topics: Retinoblastoma; Humans; Retinal Neoplasms; Disease Management
PubMed: 38615905
DOI: 10.1016/j.apjo.2024.100058 -
Life Science Alliance Dec 2023The retinoblastoma tumor suppressor protein (RB) interacts physically and functionally with a number of epigenetic modifying enzymes to control transcriptional...
The retinoblastoma tumor suppressor protein (RB) interacts physically and functionally with a number of epigenetic modifying enzymes to control transcriptional regulation, respond to replication stress, promote DNA damage response and repair, and regulate genome stability. To better understand how disruption of RB function impacts epigenetic regulation of genome stability and determine whether such changes represent exploitable weaknesses of RB-deficient cancer cells, we performed an imaging-based screen to identify epigenetic inhibitors that promote DNA damage and compromise the viability of RB-deficient cells. We found that loss of RB alone leads to high levels of replication-dependent poly-ADP ribosylation (PARylation) and that preventing PARylation by trapping PARP enzymes on chromatin enables RB-deficient cells to progress to mitosis with unresolved replication stress. These defects contribute to high levels of DNA damage and compromised cell viability. We demonstrate this sensitivity is conserved across a panel of drugs that target both PARP1 and PARP2 and can be suppressed by reexpression of the RB protein. Together, these data indicate that drugs that target PARP1 and PARP2 may be clinically relevant for RB-deficient cancers.
Topics: Poly(ADP-ribose) Polymerase Inhibitors; Epigenesis, Genetic; DNA; Chromatin; DNA Damage
PubMed: 37704395
DOI: 10.26508/lsa.202302067