Systematic review of the current status of programs and general knowledge of diagnosis and management of retinoblastoma

Plasma miR-6089 as potential diagnostic biomarker for retinoblastoma

OBJECTIVE

The purpose of this study was to screen target miRNA related to RB and explore the expression levels of target miRNA in RB and its potential value of diagnosis.

METHODS

The Affymetrix GeneChip miRNA 4.0 Array was used to screen the differential miRNAs in the plasma of 5 RB patients before and after intravenous chemotherapy, and the most significant down-regulated miRNA was selected for target miRNA. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) is used to verify the expression levels of plasma target miRNA in 30 RB patients. Then, qRT-PCR was performed to further verify the expression of target miRNA in plasma of RB patients and RB tumor tissues. Finally, receiver-operating-characteristic (ROC) curve and the area under the ROC curve (AUC) were used to evaluate the diagnostic power of plasma target miRNA.

RESULTS

The miRNA Array obtain 8 core miRNAs, 1 up-regulated and 7 down-regulated, of which miR-6089 was the most significantly down-regulated. Plasma miR-6089 levels were significantly up-regulated in RB patients. Besides, in RB tumor tissues, miR-6089 levels were also obviously up-regulated. After intravenous chemotherapy, the expression of plasma miR-6089 was significantly decreased. Furthermore, ROC curve analysis showed that miR-6089 in the plasma had a good sensitivity and specificity for distinguishing RB from the healthy control group.

CONCLUSIONS

MiR-6089 may be considered as a novel potential diagnostic biomarker for RB.

TRIAL REGISTRATION NUMBER

ChiCTR2000040154; date of registration: 2020/11/22; retrospectively registered.

miR-491-3p is Downregulated in Retinoblastoma and Inhibit Tumor Cells Growth and Metastasis by Targeting SNN

Retinoblastoma (Rb) is the most common pediatric malignant tumor of the eyes. Previous studies demonstrated that miR-491-3p is downregulated in various cancers. However, its function in Rb remains unknown. A total of 15 pairs of primary Rb tissues and adjacent noncancerous tissues were collected. Quantitative real-time PCR (qRT-PCR) was used to investigate the expression profiles of miR-491-3p. qRT-PCR, western blotting and in situ immunocytochemistry were performed to investigate the expression profiles of epithelial–mesenchymal transition-related proteins (E-cadherin, Vimentin and N-cadherin) in Rb tissues and Rb cell lines as well as cell morphology. Cell proliferation was estimated by MTS and colony formation assays. Apoptosis was determined by FACS, cell migration and invasion were analyzed using transwell chambers. MiR-491-3p’s target genes were predicted using target gene prediction databases. The interplay between miR-491-3p and SNN was evaluated through dual luciferase reporter gene assay. MiR-491-3p was significantly downregulated in mixed collection of 15 pairs of Rb tissues and Rb cell lines. Overexpression of miR-491-3p enhanced apoptosis, and significantly suppressed proliferation, migration and invasion of Rb cells. In contrast, the present of miR-491-3p inhibitor showed reversed results which apoptosis decreased, while cell proliferation of ARPE-19 cells increased. In addition, miR-491-3p increased the expression of E-cadherin, and dramatically decreased the expression of Vimentin and N-cadherin in Rb tissues and Rb cell lines, noticeable changes in morphology, too, as cells became less cohesive and more adhering. We found out that SNN was the pairing target of miR-491-3p and result showed that miR-491-3p and SNN interacted with each other. We also found out that the effects of miR-491-3p were in Rb cells were almost entirely canceled out at the overexpression of SNN. Our findings collectively suggest that miR-491-3p is an important tumor suppressor in Rb, which inhibits tumor growth and metastasis in Rb. These implicate it may be explored as a new therapeutic target in Rb.

Curcumin suppressed proliferation and migration of human retinoblastoma cells through modulating NF-κB pathway

PURPOSE

To study the effect of curcumin on proliferation and invasion of the human retinoblastoma cells and its potential mechanism.

METHODS

A cell line of retinoblastoma (WERI-Rb-1) was treated with various concentrations of curcumin (0-40 µM). Cell number was counted with CCK8 kit, and cell migration was assessed using the Transwell assay. Immunoblotting was performed to detect the proteins of metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF) as well as nuclear translocation of nuclear factor-κB (NF-κB, p65).

RESULTS

Proliferation and migration of WERI-Rb-1 cells were significantly inhibited by curcumin in a concentration-dependent manner (0-40 µM). Protein expressions of MMP-2, MMP-9 and VEGF in the WERI-Rb-1 cells were also significantly inhibited by curcumin in a concentration-dependent manner (0-40 µM). Furthermore, nuclear translocation of NF-κB (p65) was significantly inhibited by curcumin in time-dependent manner (6-24 h).

CONCLUSION

Curcumin inhibited proliferation and migration of WERI-Rb-1 cells, a cell line of human retinoblastoma, which might be through modulating NF-κB and its downstream proteins including VEGF, MMP-2, and MMP-9.

Long noncoding RNA SNHG14 promotes the aggressiveness of retinoblastoma by sponging microRNA‑124 and thereby upregulating STAT3

A long noncoding RNA called small nucleolar RNA host gene 14 (SNHG14) has been validated as a key regulator of cellular processes in multiple types of human cancer. However, to the best of our knowledge, the expression status and specific roles of SNHG14 in retinoblastoma (RB) have not been studied. The aims of the present study were to determine the expression status of SNHG14 in RB, assess the effects of SNHG14 on malignant characteristics of RB cells and investigate the mechanisms of action of SNHG14 in RB. SNHG14 expression levels in RB tissue samples and cell lines were measured by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Cell proliferation, apoptosis, migration and invasion in vitro, and tumor growth in vivo were quantitated by the Cell Counting Kit‑8 assay, flow cytometry, migration and invasion assays, and mouse tumor xenograft experiments, respectively. The target microRNA (miRNA) of SNHG14 was predicted by bioinformatics analysis and was subsequently validated by a luciferase reporter assay, RNA immunoprecipitation (RIP) assay, RT‑qPCR, and western blot analysis. SNHG14 was identified to be significantly overexpressed in RB tissues and cell lines. SNHG14 overexpression was markedly associated with the intraocular international retinoblastoma classification stage, optic nerve invasion, and differentiation grade among patients with RB. The patients in the SNHG14 high‑expression group exhibited shorter overall survival compared with the SNHG14 low‑expression group. Functional analysis revealed that SNHG14 silencing inhibited cell proliferation, migration and invasion, and increased apoptosis in vitro, and decreased tumor growth in vivo. SNHG14 directly interacted with, and functioned as a competing endogenous RNA (ceRNA) of, miR‑124, consequently upregulating signal transducer and activator of transcription 3 (STAT3). miR‑124 inhibition and STAT3 expression recovery attenuated the effects of the SNHG14 silencing on RB cells. In conclusion, SNHG14 served as a ceRNA to upregulate STAT3 by sponging miR‑124. Therefore, targeting the SNHG14/miR‑124/STAT3 pathway may be an effective therapeutic strategy against RB.

Challenge of Retinoblastoma in Mexico in 2020: Perspectives and Solutions

Early diagnosis and positive outcomes of retinoblastoma in childhood have been positively correlated with the economic wealth of high-income countries (HICs) worldwide. Adequate curability and survival rates, adherence to treatment, presence of poor prognostic initial clinical signs, and metastatic disease at diagnosis appear to have a less favorable picture in low-income countries (LICs). However, this is not always the case. An example is Argentina, where disease-free survival rates of retinoblastoma are notably higher than expected when taking into consideration its economic situation. Unfortunately, as in other Latin American LICs, retinoblastoma outcomes in Mexico are worrisome. Interestingly, the Human Development Index (HDI) in Mexico varies widely between its different geographical regions. While in some states, the HDI resembles those of high-income countries, and in others, the opposite is observed. A unifying picture of Mexico's developmental status, health resources, indicators, and other factors possibly influencing outcomes in retinoblastoma is currently unavailable. The present review explores the previously mentioned factors in Mexico and compares them to other countries. Additionally, it recommends solutions or enhancements where possible.

A temperature-sensitive phase-change hydrogel of topotecan achieves a long-term sustained antitumor effect on retinoblastoma cells

Background

Retinoblastoma (Rb) is one of the most common malignancies among children. Following early diagnosis and prompt treatment, the clinical outcome or prognosis of Rb is promising. However, the prognosis or survival rates of patients with late-stage Rb remain poor. Current therapeutic strategies for advanced Rb mainly involve the use of advanced chemotherapeutic options. However, the efficacy of these strategies is not satisfactory. Therefore, the development of novel strategies to achieve a more effective antitumor effect on late-stage Rb is of crucial importance.

Methods and materials

Topotecan was dissolved in phosphate-buffered saline and prepared into a temperature-sensitive phase-change hydrogel (termed Topo-Gel). Moreover, Topo-Gel was injected into tumor tissues formed by Y79 cells (an Rb cell line) in nude mice to examine the long-term release and long-acting antitumor effect of Topo-Gel on Rb tumors.

Results

Topo-Gel transforms from liquid to a hydrogel at near body temperatures (phase-change temperature [T_1/2] was 37.23±0.473 °C), and maintains the slow release of topotecan in Rb tumor tissues. Following the subcutaneous injection of Topo-Gel, the treatment induced long-acting inhibition of tumor growth and relieved the adverse effects associated with topotecan. Topo-Gel, a temperature-sensitive phase-change hydrogel, is a slow-release system that prolongs the presence of topotecan in Rb tissues, and preserves the efficacy of topotecan in the long term.

Conclusion

Preparation of topotecan into a temperature-sensitive phase-change hydrogel achieves a long-term sustained antitumor effect on Rb cells, and may be a useful strategy for the treatment of intraocular Rb.

Serum miR-338-5p has potential for use as a tumor marker for retinoblastoma

The aim of the present study was to investigate the expression of microRNA (miR)-338-5p in retinoblastoma(RB), thereby evaluating whether it could have potential as a biomarker to screen patients with RB from healthy controls. The results revealed that miR-338-5p was significantly upregulated in patients with RB compared with in healthy controls. There was no significant difference in the expression of miR-338-5p between patients with RB of different age, sex, tumor stage or binocular disease. Receiver operator characteristic analysis indicated that serum miR-338-5p combined with neuron-specific enolase (NSE) had a larger area under the curve compared with serum miR-338-5p alone when diagnosing RB. In addition, suppression of miR-338-5p induced slower proliferation of ACBRI-181 and Y79 cells at 2, 3, 4 and 5 days compared with the negative control group. Flow cytometric analysis indicated that transfection with miR-338-5p inhibitor leads to significant cell cycle arrest in ACBRI-181 and Y79 cells compared with in the negative control group. Furthermore, transfection with miR-338-5p inhibitor significantly decreased ACBRI-181 and Y79 cell migration and invasion, suggesting that miR-338-5p may serve an oncogenic role in the progression of RB. In conclusion, the low expression of miR-338-5p in the serum of patients with RB suggests that it may be involved in the formation of RB. Serum miR-338-5p has the potential to be a tumor marker of RB, and, in combination with NSE, miR-338-5p may improve the early diagnosis rate of RB.