SCARA5 suppresses the proliferation and migration, and promotes the apoptosis of human retinoblastoma cells by inhibiting the PI3K/AKT pathway

Paeonol upregulates expression of tumor suppressors TNNC1 and SCARA5, exerting anti-tumor activity in non-small cell lung cancer cells

Paeonol, a naturally bioactive phenolic ingredient predominantly isolated from Paeonia suffruticosa, has recently garnered significant interest as an anti-tumor agent against diverse carcinomas including non-small cell lung cancer (NSCLC). However, the anti-tumor mechanism of paeonol in NSCLC remains unclear. Cell viability, caspase-3 activity, and apoptosis were evaluated using CCK-8 assay, Caspase-3 Colorimetric Assay Kit, and flow cytometry analysis, respectively. GSE186218 was downloaded from NCBI Gene Expression Omnibus (GEO). The common genes were screened using GEO2R and Draw Venn Diagram software. Expression of troponin C type 1 (TNNC1), scavenger receptor class A member 5 (SCARA5), phosphorylated protein kinase B (AKT) (p-AKT) and AKT was examined using GEPIA database, qRT-PCR and western blot analysis. Paeonol treatment concentration-dependently inhibited cell viability and increased caspase-3 activity and apoptotic rate in NSCLC cells. Only 5 overlapping genes including TNNC1 and SCARA5 were obtained among 232 upregulated genes in GSE186218, 200 underexpressed genes in TCGA-LUAD, and 200 underexpressed genes in TCGA-LUSC according to the Venn diagram software. TNNC1 and SCARA5, two known tumor suppressors, were significantly downregulated in LUAD and LUSC tissues and NSCLC cells. Paeonol dose-dependently upregulated TNNC1 and SCARA5 expression in NSCLC cells. Paeonol suppressed the AKT pathway by upregulating TNNC1 and SCARA5 expression. AKT inhibitor attenuated the effects of TNNC1 or SCARA5 knockdown on the anti-tumor activity of paeonol. In conclusion, paeonol exhibited anti-cancer activity in NSCLC cells through inactivating the AKT pathway by upregulating TNNC1 or SCARA5.

LncRNA NEAT1 promotes angiogenesis of retinoblastoma cells through regulation of the miR-106a/HIF-1α axis

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.

Stem-Cell-Derived Extracellular Vesicles: Unlocking New Possibilities for Treating Diminished Ovarian Reserve and Premature Ovarian Insufficiency

Despite advancements in assisted reproductive technology (ART), achieving successful pregnancy rates remains challenging. Diminished ovarian reserve and premature ovarian insufficiency hinder IVF success-about 20% of in vitro fertilization (IVF) patients face a poor prognosis due to a low response, leading to higher cancellations and reduced birth rates. In an attempt to address the issue of premature ovarian insufficiency (POI), we conducted systematic PubMed and Web of Science research, using keywords "stem cells", "extracellular vesicles", "premature ovarian insufficiency", "diminished ovarian reserve" and "exosomes". Amid the complex ovarian dynamics and challenges like POI, stem cell therapy and particularly the use of extracellular vesicles (EVs), a great potential is shown. EVs trigger paracrine mechanisms via microRNAs and bioactive molecules, suppressing apoptosis, stimulating angiogenesis and activating latent regenerative potential. Key microRNAs influence estrogen secretion, proliferation and apoptosis resistance. Extracellular vesicles present a lot of possibilities for treating infertility, and understanding their molecular mechanisms is crucial for maximizing EVs' therapeutic potential in addressing ovarian disorders and promoting reproductive health.

SCARA5 in bone marrow stromal cell-derived exosomes inhibits colorectal cancer progression by inactivating the PI3K/Akt pathway

Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer worldwide. Bone marrow stromal cells (BMSCs) play an essential role in tumor development by secreting exosomes. Scavenger receptor class A member 5 (SCARA5) is a newly identified tumor suppressor. This study aimed to investigate the effects of BMSCs-derived exosomes (BMSCs-Exos) on CRC development and to explore their regulatory mechanisms. BMSCs-Exos showed an oval-shaped, bilayer membrane structure. BMSCs-Exos inhibited growth and motility of CRC cells, while BMSCs-Exos with SCARA5 knockdown significantly promoted cell proliferation and movement. Exosomal SCARA5 also effectively suppressed colorectal tumor growth in mouse xenografts. Further analysis revealed that exosomal SCARA5 inhibited the phosphorylation of protein kinase B and phosphoinositide 3-kinase in both CRC cells and tumors. In conclusion, SCARA5 in BMSCs-Exos inhibited CRC progression by inactivating PI3K/Akt, thus suggesting the potential clinical application of SCARA5-containing BMSCs-Exos for CRC treatment.

Downregulated lncRNA HOTAIR ameliorates polycystic ovaries syndrome via IGF-1 mediated PI3K/Akt pathway

OBJECTIVE

Polycystic ovarian syndrome (PCOS) is a common disorder that leads to infertility in reproductive-aged females. HOTAIR is highly expressed in various gynecological diseases and is associated with a poor prognosis. We aimed to explore the role of HOTAIR in PCOS.

METHODS

First, PCOS rats were induced using dehydroepiandrosterone and then treated with si-HOTAIR. Next, HOTAIR mRNA expression and serum hormone levels were detected. HE staining was applied to observe estrus cycle, ovarian morphology and count the number of follicles. Apoptosis in the ovary was detected by TUNEL. Thereafter, ovarian granulosa cells (GCs) were isolated from PCOS rats, transfected with si-HOTAIR and treated with LY294002 (Akt inhibitor) or IGF-1. CCK-8 and flow cytometry assays were used to evaluate cell viability and apoptosis. IGF-1, apoptosis- and PI3K/Akt pathway-associated protein expressions in ovary and GCs were also detected.

RESULTS

In in vivo experiments, si-HOTAIR decreased serum T, E₂ and LH levels but increased FSH level, restored estrus cycle, ovarian morphology and inhibited apoptosis of ovary in PCOS rats. Meanwhile, in vitro assays showed that si-HOTAIR upregulated the viability but inhibited the apoptosis of PCOS GCs. Furthermore, both in vivo and in vitro assays revealed that si-HOTAIR increased Bcl-2 expression but suppressed Bax, Bad, IGF-1 expressions and PI3K, AKT phosphorylation. However, the aforementioned effects of si-HOTAIR in vitro were further enhanced by LY294002 and partially reversed by IGF-1.

CONCLUSIONS

HOTAIR knockdown improved PCOS, and the mechanism may relate to IGF-1-mediated PI3K/Akt pathway, indicating HOTAIR may be a novel therapeutic target for PCOS.

m6A-mediated upregulation of lncRNA RMRP boosts the progression of bladder cancer via epigenetically suppressing SCARA5

Aim: This study aimed to elucidate the relationship between SCARA5 and RMRP in bladder cancer and their underlying mechanism. Methods: Biological functions were evaluated using cell-counting kit 8 assay, 5-ethynyl-2'-deoxyuridine incorporation, wound healing and Transwell assays. RNA immunoprecipitation, RNA pull-down and chromatin immunoprecipitation were employed. A xenograft tumor model in nude mice was also conducted. Results & conclusion: RMRP and SCARA5 exhibited an inverse correlation. Downregulation of RMRP significantly suppressed bladder cancer cell proliferation, migration and invasion, which was reversed by SCARA5 overexpression. RMRP recruited DNA methyltransferases to the promoter region of SCARA5, thereby triggering the methylation of the SCARA5 promoter to epigenetically suppress its expression. Our findings elucidate the machinery by which RMRP, stabilized by METTL3, exerts a promoter role in bladder cancer tumorigenesis by triggering SCARA5 methylation.

SCARA5 inhibits oral squamous cell carcinoma via inactivating the STAT3 and PI3K/AKT signaling pathways

Oral squamous cell carcinoma (OSCC) is a common tumor in the world. Despite the rapid development of medical care, OSCC is also accompanied by high incidence and mortality every year. Therefore, it is still necessary to continuously develop new methods or find new targets to treat OSCC. Previous research showed that scavenger receptor class A member 5 (SCARA5) was one of the potential biomarkers of OSCC, and its expression is significantly low in OSCC. This study aimed to explore the role and related molecular mechanisms of SCARA5 in OSCC. In this study, we found that the SCARA5 expression was lower in CAL-27 and SCC-9 cells than that in human normal oral epithelial keratinocytes. SCARA5 overexpression significantly inhibited cell proliferation and induced apoptosis of CAL-27 and SCC-9 cells. In addition, SCARA5 repressed OSCC cell epithelial-mesenchymal transformation (EMT), evidenced by increased E-cadherin expression and reduced N-cadherin expression. Finally, we found that SCARA5 could suppress STAT3, PI3K, and AKT phosphorylation. Therefore, SCARA5 was related to STAT3 and PI3K/AKT signaling pathways in OSCC. In conclusion, SCARA5 inhibited the proliferation and EMT and induced the apoptosis of OSCC cells through the inhibition of STAT3 and PI3K/AKT signaling pathways, thereby exerting a tumor suppressor effect.

SCARA5 induced ferroptosis to effect ESCC proliferation and metastasis by combining with Ferritin light chain

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) remains one of the most lethal cancers worldwide accompany with an extremely poor prognosis. Therefore, this study aims to screen for new molecules affecting ESCC and explore their mechanisms of action to provide ideas for targeted therapies for ESCC.

METHODS

Firstly, we screened out the membrane protein SCARA5 by high-throughput sequencing of the ESCC patient tissues, and RT-qPCR and WB were used to verify the differential expression of SCARA5 in esophageal cell lines, and IHC analyzed the expression localization of SCARA5 in ESCC tissue. Then, flow cytometry, wound healing assay, Transwell assay and CCK-8 assay were used to explore the effects of SCARA5 on cell cycle, migration and invasion as well as cell proliferation activity of esophageal squamous carcinoma cells. Meanwhile, transmission electron microscopy was used to detect changes in cellular mitochondrial morphology, and flow cytometry were used to detect changes in intracellular reactive oxygen metabolism, and immunofluorescence and flow cytometry were used to detect changes in intracellular Fe²⁺. Mechanistically, co-immunoprecipitation was used to detect whether SCARA5 binds to ferritin light chain, and ferroptosis-related protein expression was detected by WB. Finally, the tumor xenograft model was applied to validation the role of SCARA5 tumor growth inhibition in vivo.

RESULTS

We found that SCARA5 was aberrantly decreased in ESCC tissues and cell lines. Furthermore, we confirmed that SCARA5 suppressed the cell cycle, metastasis and invasion of ESCC cells. Meanwhile, we also found that overexpression of SCARA5 caused changes in mitochondrial morphology, accumulation of intracellular reactive oxygen species and increased intracellular Fe²⁺ in ESCC cells, which induced ferroptosis in ESCC cells. Mechanically, we validated that SCARA5 combined with ferritin light chain and increased intracellular Fe²⁺. As well as, overexpression SCARA5 induced ferroptosis by increasing ferritin light chain in nude mice subcutaneous tumors and inhibited the growth of nude mice subcutaneous tumors.

CONCLUSION

Collectively, our findings demonstrated that SCARA5 suppressed the proliferation and metastasis of ESCC by triggering ferroptosis through combining with ferritin light chain.

Effect of Eriodictyol on Retinoblastoma via the PI3K/Akt Pathway

Retinoblastoma (RB) is one of the most common intraocular malignancies in children, which causes vision loss and even threatens life. Eriodictyol is a natural flavonoid with strong anticancer activity. Some studies have shown that eriodictyol exerts anticancer effects in glioma, colon cancer, and lung cancer; however, no studies have reported the anticancer effects of eriodictyol on RB. Therefore, the aim of this study was to investigate the anticancer activity of eriodictyol against the RB Y79 cell line and its potential mechanism of action. Interestingly, we found that eriodictyol inhibited the proliferation, migration, and invasion of Y79 cells in a dose-dependent manner and decreased the expression of MMP-2 and MMP-9 proteins in the cells. In addition, eriodictyol-induced apoptosis in Y79 cells was assessed by flow cytometry and immunoblotting. Here, our study revealed that eriodictyol dose dependently inhibited the activation of the PI3K/Akt signaling pathway. Notably, the effect of eriodictyol on RB apoptosis was reversed by a PI3K agonist 740 Y-P. In conclusion, our study shows that eriodictyol effectively inhibits proliferation, migration, and invasion and induces apoptosis in RB cell lines, which may be the result of blocking the PI3K/Akt signaling pathway. Thus, eriodictyol may provide a new theoretical basis for exploring targeted antitumor natural therapies.

Publication Trends of Research on Retinoblastoma During 2001-2021: A 20-Year Bibliometric Analysis

Background: Retinoblastoma is the most common primary intraocular malignancy of childhood. Despite high survival and eye salvage as the result of various types of therapies, retinoblastoma remains a disease that places a considerable burden on developing countries. Our study attempted to analyse the research trends in retinoblastoma research and compare contributions from different countries, institutions, journals, and authors.

Methods: We extracted all publications concerning retinoblastoma from 2001 to 2021 from the Web of Science database. Microsoft Excel and VOSviewer were employed to collect publication data, analyse publication trends, and visualize relevant results.

Results: A total of 1,675 publications with 30,148 citations were identified. The United States contributed the most publications (643) and citations (16,931 times) with the highest H-index value (67) as of February 4, 2021. China ranked second in the number of publications (259), while ranking fourth in both citations (2,632 times) and the H-index (26) ranked fourth. The British Journal of Ophthalmology was the most productive journal concerning retinoblastoma, and Abramson DH had published the most papers in the field. Keywords were categorized into three clusters; tumor-related research, clinical research, and management-related research. The keywords “intravitreal,” “intraarterial,” and “intravenous” appeared the most frequently, with the average appearing year being 2018.1, 2017.7, and 2017.1, respectively. Management-related research has been recognized as a heavily researched topic in the field.

Conclusion: We conclude that the United States, China, and India made the most exceptional contributions in the field of retinoblastoma research, while China still has a disparity between the quantity and quality of publications. Management-related research, including intravitreal, intraarterial, and intravenous chemotherapy was considered as a potential focus for future research.