Multimodal imaging for the differential diagnosis and efficacy evaluation of intraocular retinoblastoma in children with selective ophthalmic artery infusion.

Background: Retinoblastoma (RB) is the most common malignant tumor in children under the age of 3 years and is associated with a high disability and mortality rate. The aim of this study was, first, to evaluate the clinical efficacy of multimodal imaging in differentially diagnosing RB in children and in predicting the efficacy of selective ophthalmic artery infusion (SOAI) and, second, to identify the factors associated with this efficacy. Methods: This study retrospectively collected the data from 256 children with unilateral RB and intraocular involvement, including multimodal imaging magnetic resonance imaging (MRI), computed tomography (CT), and clinical characteristics. Among the cases, 33 with both CT and MRI data available were used to evaluate the diagnostic accuracy in distinguishing RB, with histopathological results serving as the gold standard. Additionally, a retrospective analysis was conducted on the MRI and clinical characteristics of 256 cases of unilateral RB with intraocular involvement before SOAI treatment. The predictive ability of imaging features and clinical characteristics for the treatment efficacy of children was analyzed, and the differences in globe salvage rates and visual preservation based on different tumor stages were evaluated. Results: The diagnostic accuracy of CT imaging for RB was 96.96% while that of MRI was 84.84%, with both showing high consistency with the histopathological results. CT images demonstrated a posterior intraocular mass with a high-density appearance, with spots, patches, or clustered calcifications visible within the tumor. The CT values were mostly above 100 Hounsfield units (HU), and enhanced scanning showed varying degrees of enhancement in noncalcified masses. MRI showed low or moderate signal intensity on T1-weighted images and moderate-to-high signal intensity on T2-weighted images, with significant enhancement after contrast administration. Tumors with more calcifications showed long T1 and short T2 signals. Patients with better prognosis had a higher delta signal increase (ΔSI), a greater distance from the optic disc, smaller tumor diameter, absence of implantation nodules or smaller implantation range, endogenous growth pattern, smaller extent of retinal detachment, absence of clinical high-risk factors, no vitreous hemorrhage, no globe shrinkage, and smaller calcification volume. The distance between the tumor and optic disc, clinical high-risk factors, and tumor growth pattern were found to be independent factors associated with prognosis. The rate of successful globe salvage and visual acuity decreased with increasing tumor stage. Conclusions: CT and MRI are highly valuable for the comprehensive assessment of tumors in pediatric RB. MRI alone can complete a comprehensive assessment of patients with RB and thus allow for the reduction radiation dose in children. Calcification of the tumor is crucial for diagnosis, and imaging findings can serve to inform patient prognosis and treatment planning. The distance between the tumor and optic disc, clinical high-risk factors, and tumor growth pattern are closely related to the prognosis of children.

PEITC Induces DNA Damage and Inhibits DNA Repair-Associated Proteins in Human Retinoblastoma Cells In Vitro.

Phenethyl isothiocyanate (PEITC), a natural product, exists in biological activities, including anticancer activity in many human cancer cells. No information shows that PEITC affects DNA damage in human retinoblastoma (RB) cells in vitro. In this study, the aim of experiments was to determine whether PEITC decreased total viable cell number or not by inducing protein expressions involved in DNA damage and repair in Y79 RB cells in vitro. Total cell viability was measured by PI exclusion assay, and PEITC reduced the total Y79 viable cell numbers in a dose-dependent manner. DNA condensation and DNA impairment were conducted by DAPI staining and comet assays, respectively, in Y79 cells. The findings show that PEITC induced DNA condensation dose-dependently based on the brighter fluorescence of cell nuclei stained by DAPI staining. PEITC-induced DNA damage showed a more extended DNA migration smears than that of the control, which was performed by a comet assay. Western blotting was performed to measure the protein expressions involved in DNA damage and repair, which showed that PEITC at 2.5-10 µM increased NRF2, HO-1, SOD (Mn), and catalase; however, it decreased SOD (Cu/Zn) except 10 µM PEITC treatment, and decreased glutathione, which were associated with oxidative stress. Furthermore, PEITC increased DNA-PK, MDC1, H2A.XpSer139, ATMpSer1981, p53, p53pSer15, PARP, HSP70, and HSP90, but decreased TOPIIα, TOPIIß, and MDM2pSer166 that were associated with DNA damage and repair mechanism in Y79 cells. The examination from confocal laser microscopy shows that PEITC increased H2A.XpSer139 and p53pSer15, and decreased glutathione and TOPIIα in Y79 cells. In conclusion, the cytotoxic effects of PEITC on reducing the number of viable cells may be due to the induction of DNA damage and the alteration of DNA repair proteins in Y79 cells in vitro.

The Traces of Dysregulated lncRNAs-Associated ceRNA Axes in Retinoblastoma: A Systematic Scope Review.

PURPOSE: Long non-coding RNAs are an essential component of competing endogenous RNA regulatory axes and play their role by sponging microRNAs and interfering with the regulation of gene expression. Because of the broadness of competing endogenous RNA interaction networks, they may help investigate treatment targets in complicated disorders. METHODS: This study performed a systematic scoping review to assess verified loops of competing endogenous RNAs in retinoblastoma, emphasizing the competing endogenous RNAs axis related to long non-coding RNAs. We used a six-stage approach framework and the PRISMA guidelines. A systematic search of seven databases was done to locate suitable papers published before February 2022. Two reviewers worked independently to screen articles and collect data. RESULTS: Out of 363 records, fifty-one articles met the inclusion criteria, and sixty-three axes were identified in desired articles. The majority of the research reported several long non-coding RNAs that were experimentally verified to act as competing endogenous RNAs in retinoblastoma: XIST/NEAT1/MALAT1/SNHG16/KCNQ1OT1, respectively. At the same time, around half of the studies investigated unique long non-coding RNAs. CONCLUSIONS: Understanding the many features of this regulatory system may aid in elucidating the unknown etiology of Retinoblastoma and providing novel molecular targets for therapeutic and clinical applications.

Expression of YAP suppresses cell proliferation and elevates the sensitivity of chemotherapy in retinoblastoma cells through lipid-peroxidation induced ferroptosis.

BACKGROUND: Retinoblastoma (RB) is a retinal cancer most commonly occurred in young children. Cisplatin and etoposide had been confirmed as chemotherapy drugs in the treatment of RB, even though the phenomenon of chemotherapeutic resistance has been occurring in clinical treatment frequently. RB has been reported to be a tumor with reduced expression of yes-associated protein (YAP). However, the role of YAP protein and its correlation with the chemotherapy effect in RB still remains unknown. METHODS: Here we used human RB cell lines Y79 and RB3823 to construct YAP over-expression cell lines for exploring the specific role of YAP. In vitro, a series of techniques and methods were used to identify the biological role of YAP in RB, such as Agilent Seahorse assay, lipid peroxidation assay, intracellular reactive oxygen species (ROS) measurement, flow cytometry apoptosis assay, and other basic experimental techniques, among others. RESULTS: The cell growth and cytology experimental results found YAP can inhibit the proliferation of RB cells and promote their apoptosis (Y79 32.71% vs. 3.75%; RB3823 40.32% vs. 6.73%). The mitochondrial fuel flex test, lipid peroxide and ROS measurement confirmed that YAP over-expression could promote mitochondrial fatty-acids ß-oxidation and lipid peroxidation in RB cells. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis for the expression of lipid peroxidation related factors imply that YAP over-expression caused ferroptosis in RB cell lines. In addition, YAP transcription specific activator PY-60 (10 µM) further improved the sensitivity of cisplatin/etoposide. CONCLUSIONS: Our research results found the expression of YAP inhibits cell proliferation and promoted lipid peroxidation induced ferroptosis in RB. Interestingly, the mitochondrial oxidative phosphorylation shows an increased fatty acid dependency and decreased glucose dependency. As a result, this phenomenon improved the sensitivity of RB to cisplatin/etoposide chemotherapy in vitro. Our finding provides a potential therapeutic target for RB chemotherapy.

miRNAs as potential game-changers in retinoblastoma: Future clinical and medicinal uses.

Retinoblastoma (RB) is a rare tumor in children, but it is the most common primitive intraocular malignancy in childhood age, especially those below three years old. The RB gene (RB1) undergoes mutations in individuals with RB. Although mortality rates remain high in developing countries, the survival rate for this type of cancer is greater than 95-98% in industrialized countries. However, it is lethal if left untreated, so early diagnosis is essential. As a non-coding RNA, miRNA significantly impacts RB development and treatment resistance because it can control various cellular functions. In this review, we illustrate the recent advances in the role of miRNAs in RB. That includes the clinical importance of miRNAs in RB diagnosis, prognosis, and treatment. Moreover, the regulatory mechanisms of miRNAs in RB and therapeutic interventions are discussed.

Integrated analysis of multiple bioinformatics studies to identify microRNA-target gene-transcription factor regulatory networks in retinoblastoma.

Background: In children, retinoblastoma (RB) is one of the most common primary malignant ocular tumors and has a poor prognosis and high mortality. To understand the molecular mechanisms of RB, we identified microRNAs (miRNAs), key genes and transcription factors (TFs) using bioinformatics analysis to build potential miRNA-gene-TF networks. Methods: We collected three gene expression profiles and one miRNA expression profile from the Gene Expression Omnibus (GEO) database. We used the limma R package to identify overlapping differentially expressed genes (DEGs) and differentially expressed miRNAs in RB tissues compared to noncancer tissues. The robust rank aggregation (RRA) method was implemented to identify key genes among the DEGs. Then, miRNA-key gene-TF networks were built using the online tools TransmiR and miRTarBase. Next, we used RT-qPCR to confirm the results. Results: We identified 180 DEGs in RB tissues compared to nontumor tissues using integrative analysis, among which 109 genes were upregulated and 71 were downregulated. Gene ontology (GO) analysis revealed that these DEGs were primarily involved with chromosome segregation, condensed chromosome and DNA replication origin binding. The most highly enriched pathways obtained in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were cell cycle, DNA replication, homologous recombination, P53 signaling pathway and pyrimidine metabolism. Furthermore, two key differentially expressed miRNAs (DEMs) were also established: let-7a and let-7b. Finally, the potential regulatory networks of miRNA-target gene-TFs were examined. Conclusions: This study identified key genes and built miRNA-target gene-TF regulatory networks in RB, which will deepen our understanding of the molecular mechanisms involved in the development of RB. These key genes and miRNAs may be potential targets and biomarkers for RB diagnosis and therapy.

Chemotherapy modulates CDK4/6 inhibitors resistance in metastatic breast cancer by Rb1 mutations: a case report and literature review.

Cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) plays a major role in breast cancer therapeutics acting through preventing the cell cycle from G1 to the S phase. Recently, Endocrine therapy combined with CDK4/6i represented a major milestone in hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer treatment. However, the resistance of CDK4/6i is clinically common, and the mechanism remains to be clarified. Retinoblastoma (Rb) is a negative regulator of cell cycle. It inhibits cell cycle transition by binding to E2F transcription factors, and prevent cells division in this way. Rb is regulated by phosphorylation. The CDK4/6i have been shown to affect cancer by blocking phosphorylation of Rb. In addition, decreasing estrogen signal has been confirmed to reduce cyclin D-CDK4/6 complexing. Currently, FCN-437c is a new CDK4/6i that is in clinical trials. Here, we present the case of an HR-positive and HER2-negative patient whose disease continued to rapidly progress after receiving FCN-437c. To determine why, we did a series of examinations and found that her Rb1 had mutated after using CDK4/6i. To our surprise, the Rb1 mutations recovered after treatment with eribulin, and CDK4/6i was shown to exert a renewed effect. In this way, a hypothesis was made that eribulin may influence the pathway of cyclin D- CDK4/6- Rb- E2F by effecting in Rb. This case provides new insights into strategies for CDK4/6i therapy resistance options and shows the significance of next-generation sequencing in the clinic.

Anticancer activity of ursolic acid on retinoblastoma cells determined by bioinformatics analysis and validation.

BACKGROUND: This article aims to explore whether ursolic acid (UA) inhibits the progression of retinoblastoma (Rb) by regulating stearoyl-CoA desaturase (SCD). METHODS: The Gene Expression Omnibus (GEO) database was used to filter the chip, then the GEO2R software was used to analyze the microarray data (GSE97508, GSE24673, and GSE110811). Gene set enrichment analysis (GSEA) was used to analyze the relationship between the expression level of SCD and the proliferation, migration, invasion, and inflammation in Rb patients. SO-RB50 and Y79 cell proliferation, migration, and invasion were assessed by the CCK-8 assay, the colony formation assay, the Transwell assay, and the wound scratch test. The protein expression levels of SCD were measured by western blot. The mRNA expression levels of IL-8, IL-6, CXCL1, and CCL2 were measured by RT-qPCR. The protein expression levels of IL-8 and IL-6 were measured by ELISA. A xenograft nude mouse model was established to evaluate the effect of UA on tumor growth in male BALB/c mice. RESULTS: The expression levels of SCD were related to cell proliferation, migration, invasion, and inflammation. UA inhibited SO-RB50 and Y79 cell proliferation, migration, and invasion. At the same time, UA suppressed tumor growth in the xenograft nude mouse model. Overexpression of SCD promoted SO-RB50 and Y79 cell proliferation, migration, invasion, and inflammation, while SCD knockout inhibited SO-RB50 and Y79 cell proliferation, migration, invasion, and inflammation. Importantly, UA inhibited the proliferation, migration, and invasion of Rb cells through SCD inhibition. CONCLUSIONS: UA inhibited the proliferation, migration, and invasion of Rb cells through SCD. This provides a new scientific basis for targeted therapy of Rb.

Cellular senescence limits translational readthrough.

The origin and evolution of cancer cells is considered to be mainly fueled by DNA mutations. Although translation errors could also expand the cellular proteome, their role in cancer biology remains poorly understood. Tumor suppressors called caretakers block cancer initiation and progression by preventing DNA mutations and/or stimulating DNA repair. If translational errors contribute to tumorigenesis, then caretaker genes should prevent such errors in normal cells in response to oncogenic stimuli. Here, we show that the process of cellular senescence induced by oncogenes, tumor suppressors or chemotherapeutic drugs is associated with a reduction in translational readthrough (TR) measured using reporters containing termination codons withing the context of both normal translation termination or programmed TR. Senescence reduced both basal TR and TR stimulated by aminoglycosides. Mechanistically, the reduction of TR during senescence is controlled by the RB tumor suppressor pathway. Cells that escape from cellular senescence either induced by oncogenes or chemotherapy have an increased TR. Also, breast cancer cells that escape from therapy-induced senescence express high levels of AGO1x, a TR isoform of AGO1 linked to breast cancer progression. We propose that senescence and the RB pathway reduce TR limiting proteome diversity and the expression of TR proteins required for cancer cell proliferation.

Clinical features and imaging manifestations of retinoblastoma with hepatic metastasis.

Clinical data of five patients with hepatic metastases of retinoblastoma were analyzed retrospectively (two had bilateral tumors three had unilateral intraocular tumors). On computed tomography, multiple and single low-density foci were observed. Four patients had tumor remission, and one showed no response after chemotherapy. Three patients who underwent enucleation were at high risk for extensive choroidal invasion. Central nervous system and bone metastases occurred in all five patients. Neuron-specific enolase and lactate dehydrogenase levels were significantly elevated in all patients. Two patients died (not from hepatic metastasis). Three patients (one with tumor progression and two with shorter courses) are continuing treatment.

The role for intra-arterial chemotherapy for refractory retinoblastoma: a systematic review.

BACKGROUND: Intra-arterial chemotherapy is a new retinoblastoma treatment associated with high rates of globe salvage that has been widely adopted for primary treatment of retinoblastoma but is less frequently used as secondary treatment for refractory retinoblastoma. This systematic review aims to summarize the reported outcomes of intra-arterial chemotherapy for refractory retinoblastoma. METHODS: We conducted a systematic review of studies published on PubMed, Medline, and Embase from 2011 to 2021 reporting globe salvage rates following intra-arterial chemotherapy for secondary treatment of refractory retinoblastoma. RESULTS: Our search yielded 316 studies, and 24 met inclusion criteria. The 24 included studies were comprised of 1366 patients and 1757 eyes. Among these, 1184 (67%) eyes received secondary indication treatment, and globe salvage was achieved for 776 of these 1184 eyes (64%). Sixteen studies reported cannulation success rates from 71.8 to 100%. Pooled analysis of subjects revealed 21 patients (2.6%) with metastatic disease and 26 deaths (3%) during study follow-up periods (7-74 months). The most common ocular complications were vitreous hemorrhage (13.2%), loss of eyelashes (12.7%), and periocular edema (10.5%). The most common systemic complications were nausea/vomiting (20.5%), neutropenia (14.1%), fever (8.2%), and bronchospasm (6.2%). CONCLUSIONS: Intra-arterial chemotherapy is associated with high rates of globe salvage and low rates of serious complications in patients with refractory retinoblastoma. Unfortunately, current literature is predominantly comprised of retrospective case studies, and further high-quality evidence is necessary to inform clinical practice.

TP53/miR-129/MDM2/4/TP53 feedback loop modulates cell proliferation and apoptosis in retinoblastoma.

Retinoblastoma (RB) is commonly-seen cancer in children. The p53 pathway dysfunction, which can lead to elevated MDM2 or MDM4 (p53 antagonists) protein expression, is frequently observed in almost all human cancers, including RB. The present study attempted to investigate the underlying mechanism from the perspective of non-coding RNA regulation. Here, we demonstrated that p53 and miR-129 were positively correlated with each other in RB. miR-129 directly targeted MDM2/4 to inhibit expression, therefore counteracting MDM2/4-mediated p53 signaling suppression and modulating RB cell proliferation and apoptosis. Moreover, p53 could activate the transcription of miR-129 via binding to the miR-129 promoter region, therefore forming a regulatory loop with MDM2/4 to affect RB progression. Altogether, the p53/miR-129/MDM2/4/p53 regulatory loop can modulate RB cell growth. We provide a solid experimental basis for developing novel therapies for RB.

Case report: Delayed retinoblastoma relapse in a lymph node after 9 years of complete remission.

Retinoblastoma (RB) is the most common primary intraocular malignancy of childhood. Recurrence of RB often occurs within 6 months to 1 year after the end of treatment. Orbital tissue is the most common site of recurrence in children who have undergone enucleation; other sites include the central nervous system, bone, bone marrow, lymph nodes, and other organs. Here, we describe an adolescent girl who presented with RB recurrence and metastasis in a distant lymph node after 9 years of complete remission. The tumor was an incidental finding during a routine examination and was misdiagnosed as lymphadenitis. After histopathologic examination of an aspiration biopsy sample, the correct diagnosis of recurrent metastatic RB was made. Systemic chemotherapy and surgical excision were provided; the patient remained tumor-free during the 6-month follow-up period. RB often relapses within 1 year after treatment; orbital tissue is the most common site of recurrence. However, our patient's case was unique in terms of delayed relapse and the presence of a single metastatic site; these findings may provide new insights into the behavior of RB. Furthermore, this case report indicates the need for lifelong follow-up of children with RB. Oncologists should be vigilant when treating patients with a history of RB, because complete remission does not mean complete safety; long-term recurrence and metastasis may occur. Lifelong follow-up is necessary for children with RB. Complete remission might be achieved after active and standardized treatment.

TUG1 promotes retinoblastoma progression by sponging miR-516b-5p to upregulate H6PD expression.

BACKGROUND: Retinoblastoma (RB), depicted as an aggressive eye cancer, mainly occurs in infancy and childhood and is followed by high mortality and poor prognosis. Increasing evidence has revealed that long noncoding RNA taurine upregulated gene 1 (TUG1) is closely linked to the progression of diverse cancers. Nonetheless, the specific function and molecular regulatory mechanism of TUG1 in RB still need to be explored. METHODS: To explore the specific role of TUG1 in RB. TUG1 expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell counting kit-8 (CCK-8), colony formation, 5-ethynyl-2'-deoxyuridine (EdU), caspase-3, terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) and western blot assays were utilized to study the role of TUG1 in RB. The binding relation between miR-516b-5p and TUG1 or hexose-6-phosphate dehydrogenase/glucose 1-dehydrogenase (H6PD) was analyzed by luciferase reporter and RNA immunoprecipitation (RIP) assays. RESULTS: The expression of TUG1 was upregulated in RB cells. TUG1 knockdown repressed proliferation ability and promoted apoptosis ability of RB cells. Moreover, TUG1 could bind with miR-516b-5p, which targeted H6PD in RB. In addition, the expression of H6PD was negatively and positively regulated by miR-516b-5p and TUG1 in RB, respectively. Finally, H6PD overexpression could partially offset the effects of TUG1 deficiency on cell proliferation and apoptosis. CONCLUSIONS: TUG1 promoted the development of RB by sponging miR-516b-5p to upregulate H6PD expression, which might provide a new thought for researching RB-related molecular mechanism.

Exploration of retinoblastoma pathogenesis with bioinformatics.

BACKGROUND: Differentially expressed genes (DEGs) from retinoblastoma (RB) tissues play key roles in the progression of RB. However, the role of DEGs in different subtypes and stages of RB has not yet been systematically analyzed. METHODS: In this study, the DEGs for tumor and adjacent from 3 RB data sets GSE24673, GSE97508, and GSE110811 were analyzed with regard to the different subtypes and stages of the disease. RESULTS: Through comparison with adjacent tissues, a total of 78 upregulated genes and 155 downregulated genes from the RB tissues were identified across the 3 data sets. Gene set enrichment analysis (GSEA) showed that the 3 representative genes CDK1, CDC20, and BUB1, which were all upregulated, could promote the cell cycle in RB. Compared with adjacent tissues in GSE97508, a total of 19 gigantol-targeted genes were predicted to be upregulated in invasive RB tissues. On the other hand, DEGs for tumor and adjacent from 3 RB data sets GSE24673, GSE97508, and GSE110811 were integrated with regard to invasiveness and stages of the disease, and another 19 DEGs were subsequently identified. Among these genes, UHRF1 was the only identified upregulated gene, while the other 18 were all downregulated genes. Cell Counting Kit-8 (CCK-8) experiment and GSEA results showed that UHRF1 can promote the proliferation and invasion of RB. Conversely, the downregulated representative gene CADM1 is a tumor suppressor gene, which can inhibit the progression of RB. CONCLUSIONS: This study indicated that the verified DEGs are continuously and consistently expressed in different subtypes and stages of RB. These DEGs may be the key to understanding the development and invasion of RB.

Netrin-1 promotes retinoblastoma-associated angiogenesis.

BACKGROUND: Retinoblastoma (Rb) is the most common intraocular cancer of infancy and childhood, with an incidence of nearly 0.006% in all live births. Although a functional loss or inactivation of both alleles of the retinoblastoma 1 (RB1) gene during retinal development appears to be the predominant etiology for Rb, genes associated with tumor angiogenesis are also likely to be involved in the development of this condition. Netrin-1 is a factor that regulates pathological angiogenesis, while its role in Rb is largely unknown. The present study examined the role of netrin-1 in Rb. METHODS: The expression of netrin-1 in Rb was assessed using public databases and using clinical specimens by RT-qPCR for mRNA and by ELISA for protein. The expression of netrin-1 was suppressed in Rb by siRNA and the effects on cell growth were determined by a CCK-8 assay, while the effects on angiogenesis were examined in vitro using human umbilical vein endothelial cell (HUVEC) assays and in vivo by quantification of tumor vessel density. RESULTS: Analysis of published databases revealed that the netrin-1 gene is significantly upregulated in Rb, which was confirmed by immunohistochemistry on clinical specimens. Inhibition of netrin-1 in Rb cell lines significantly reduced their effects on angiogenesis in vitro using a HUVEC co-culture assay without affecting cell growth. Inhibition of netrin-1 expression in vivo suppressed the growth of grafted Rb, and this effect could be abolished by co-expression of vascular endothelial growth factor A (VEGF-A). CONCLUSIONS: This data demonstrated a novel role for netrin-1 in the regulation of Rb-associated cancer vascularization and may represent a novel therapeutic target for patients with Rb.

Effect of miR-215 on the Expression of Tumor Suppressor Gene Rb1 in Retinoblastoma Cell Lines.

BACKGROUND: Effect of miR-215 on the expression of tumor suppressor gene retinoblastoma (Rb)1 in Rb cell lines was investigated. METHODS: A total of 128 patients were selected. The expression of miR-215 in cancer and adjacent healthy tissues of the 128 patients was detected by reverse transcription-quantitative PCR (RT-qPCR). HXO-Rb44 and Y79 cell lines were transfected with miR-215 analogs or miR-215 inhibitors, and the expression of Rb1 protein in the cell lines was detected by western blotting. RESULTS: The expression of miR-215 in the adjacent healthy tissues of patients was significantly lower than that in cancer tissues (P<0.001). The expression of miR-215 in Y79 and HXO-Rb44 cells was significantly higher than that in APRE-19 cells (P<0.001). The expression of miR-215 in HXO-Rb44 cells was significantly higher than that in Y79 cells (P<0.001). The expression of miR-215 was statistically different from the degree of differentiation and nerve infiltration (P<0.05). The expression of Rb1 in cancer tissues was significantly lower than that in adjacent tissues (P<0.001), the expression of APRE-19 was significantly higher than that in Y79 and HXO-Rb44 cells (P<0.001), and the expression of Rb1 in HXO-Rb44 cells was significantly higher than that in Y79 cells (P<0.05). There was a negative correlation between miR-215 and Rb1 in the tissues of patients, and Rb1 expression decreased with the increase of miR-215 (r=-0.576, P<0.001). CONCLUSION: miR-215 is highly expressed in Rb cell lines, and is related to the clinicopathological features of this disease.

Long non-coding RNA TP73-AS1 promotes TFAP2B-mediated proliferation, metastasis and invasion in retinoblastoma via decoying of miRNA-874-3p.

Retinoblastoma (RB) is one of the most common ophthalmic tumors, and most of the patients have been identified as advanced at the time of diagnosis, which is directly related to high mortality. Recent studies showed that long noncoding RNA (lncRNA) and miRNAs play key roles in the development、progression、or treatment of cancer, such as RB. However, the role of lncRNA -TP73-AS1 in RB remains unclear. In this study, we performed functional and mechanistic investigation of miRNA-874-3p-TP73-AS1 interaction in RB. The experiments results revealed that miRNA-874-3p had anti-oncogenic functions in RB. Moreover, the bioinformatics analysis shown that TP73-AS1 could bind to miRNA-874-3p. TP73-AS1 was inversely correlated with miRNA-874-3p expression. Furthermore, studies confirmed that TP73-AS1 negatively regulated miRNA-874-3p expression via functioning as a ceRNA. In a word, our results suggest that the TP73-AS1/ miRNA-874-3p / TFAP2B (transcription factor activating enhancer-binding protein 2B) pathway contributes to the progression of RB, which may provide novel insights into the function of lncRNA-driven retinoblastogenesis. Graphical abstract.

Long noncoding RNA UCA1 facilitates cell proliferation and inhibits apoptosis in retinoblastoma by activating the PI3K/Akt pathway.

BACKGROUND: This study aimed to explore the effects of the long noncoding RNA (lncRNA)-UCA1 on retinoblastoma (RB) and the potential underlying molecular mechanisms. METHODS: The expression of lncRNA-UCA1 was measured by qRT-RCR in both RB tissues and the RB cell lines HXO-RB44 and Y79. The relationship between lncRNA-UCA1 expression and the clinical characteristics of RB patients was evaluated. Cell proliferation, colony formation, and apoptosis and the cell cycle of HXO-RB44 and Y79 cells were evaluated by the cell counting kit-8 (CCK-8) assay, colony formation assay, and flow cytometry, respectively. In addition, the expression levels of PCNA, caspase-3, survivin, p16, p21, CDK2, PI3K, p-PI3K, Akt, p-Akt, and S6k in HXO-RB44 and Y79 cells were measured by Western blotting. RESULTS: LncRNA-UCA1 was highly expressed in both RB tissues and the RB cell lines HXO-RB44 and Y79. Moreover, lncRNA-UCA1 expression levels in RB patients were correlated with tumour size, optic nerve invasion, and pathologic grade. LncRNA-UCA1 promoted cell proliferation and cell cycle progression and inhibited apoptosis in HXO-RB44 and Y79 cells. LncRNA-UCA1 overexpression dramatically increased the expression of S6k and the phosphorylation of PI3K and Akt in RB cells. Treatment with the PI3K inhibitor LY294002 reversed the effects of lncRNA-UCA1 on RB cell proliferation, apoptosis, and cell cycle progression. CONCLUSIONS: Our study showed that lncRNA-UCA1 could promote cell proliferation and cell cycle progression and inhibit cell apoptosis in RB by activating the PI3K/Akt pathway.

G Protein-Coupled Receptor Systems and Their Role in Cellular Senescence.

Aging is a complex biological process that is inevitable for nearly all organisms. Aging is the strongest risk factor for development of multiple neurodegenerative disorders, cancer and cardiovascular disorders. Age-related disease conditions are mainly caused by the progressive degradation of the integrity of communication systems within and between organs. This is in part mediated by, i) decreased efficiency of receptor signaling systems and ii) an increasing inability to cope with stress leading to apoptosis and cellular senescence. Cellular senescence is a natural process during embryonic development, more recently it has been shown to be also involved in the development of aging disorders and is now considered one of the major hallmarks of aging. G-protein-coupled receptors (GPCRs) comprise a superfamily of integral membrane receptors that are responsible for cell signaling events involved in nearly every physiological process. Recent advances in the molecular understanding of GPCR signaling complexity have expanded their therapeutic capacity tremendously. Emerging data now suggests the involvement of GPCRs and their associated proteins in the development of cellular senescence. With the proven efficacy of therapeutic GPCR targeting, it is reasonable to now consider GPCRs as potential platforms to control cellular senescence and the consequently, age-related disorders.