Anticancer effects of melatonin via regulating lncRNA JPX-Wnt/β-catenin signalling pathway in human osteosarcoma cells

Role of melatonin in carcinogenesis and metastasis: From mechanistic insights to intermeshed networks of noncoding RNAs

In recent years, seminal studies have been devoted to unraveling the puzzling mysteries associated with the cancer preventive/inhibitory role of melatonin. Our current knowledge of the translational mechanisms and the detailed structural insights have highlighted the characteristically exclusive role of melatonin in the inhibition of carcinogenesis and metastatic dissemination. This mini-review outlines recent discoveries related to mechanistic role of melatonin in prevention of carcinogenesis and metastasis. Moreover, another exciting facet of this mini-review is related to phenomenal breakthroughs linked with regulation of noncoding RNAs by melatonin in wide variety of cancers.

Deciphering chemoresistance in osteosarcoma: Unveiling regulatory mechanisms and function through the lens of noncoding RNA

Osteosarcoma (OS) is a primary malignant bone tumor and is prevalent in children, adolescents, and elderly individuals. It has the characteristics of high invasion and metastasis. Neoadjuvant chemotherapy combined with surgical resection is the most commonly used treatment for OS. However, the efficacy of OS is considerably diminished by chemotherapy resistance. In recent years, noncoding RNAs (ncRNAs), including microRNAs, long noncoding RNAs, and circular RNAs, are hot topics in the field of chemotherapy resistance research. Several studies have demonstrated that ncRNAs are substantially associated with chemoresistance in OS. Thus, the present study overviews the abnormally expressed ncRNAs in OS and the molecular mechanisms involved in chemoresistance, with an emphasis on their function in promoting or inhibiting chemoresistance. ncRNAs are expected to become potential therapeutic targets for overcoming drug resistance and predictive biomarkers in OS, which are of great significance for enhancing the therapeutic effect and improving the prognosis.

Melatonin in cancer biology: pathways, derivatives, and the promise of targeted delivery

Melatonin, historically recognized for its primary role in regulating circadian rhythms, has expanded its influence particularly due to its wide range of biological activities. It has firmly established itself in cancer research. To highlight its versatility, we delved into how melatonin interacts with key signaling pathways, such as the Wnt/β-Catenin, PI3K, and NF-κB pathways, which play foundational roles in tumor development and progression. Notably, melatonin can intricately modulate these pathways, potentially affecting various cellular functions such as apoptosis, metastasis, and immunity. Additionally, a comprehensive review of current clinical studies provides a dual perspective. These studies confirm melatonin's potential in cancer management but also underscore its inherent limitations, particularly its limited bioavailability, which often relegates it to a supplementary role in treatments. Despite this limitation, there is an ongoing quest for innovative solutions and current advancements include the development of melatonin derivatives and cutting-edge delivery systems. By synthesizing the past, present, and future, this review provides a detailed overview of melatonin's evolving role in oncology, positioning it as a potential cornerstone in future cancer therapeutics.

Unveiling the Protective Role of Melatonin in Osteosarcoma: Current Knowledge and Limitations

Melatonin, an endogenous neurohormone produced by the pineal gland, has received increased interest due to its potential anti-cancer properties. Apart from its well-known role in the sleep-wake cycle, extensive scientific evidence has shown its role in various physiological and pathological processes, such as inflammation. Additionally, melatonin has demonstrated promising potential as an anti-cancer agent as its function includes inhibition of tumorigenesis, induction of apoptosis, and regulation of anti-tumor immune response. Although a precise pathophysiological mechanism is yet to be established, several pathways related to the regulation of cell cycle progression, DNA repair mechanisms, and antioxidant activity have been implicated in the anti-neoplastic potential of melatonin. In the current manuscript, we focus on the potential anti-cancer properties of melatonin and its use in treating and managing pediatric osteosarcoma. This aggressive bone tumor primarily affects children and adolescents and is treated mainly by surgical and radio-oncological interventions, which has improved survival rates among affected individuals. Significant disadvantages to these interventions include disease recurrence, therapy-related toxicity, and severe/debilitating side effects that the patients have to endure, significantly affecting their quality of life. Melatonin has therapeutic effects when used for treating osteosarcoma, attributed to its ability to halt cancer cell proliferation and trigger apoptotic cell death, thereby enhancing chemotherapeutic efficacy. Furthermore, the antioxidative function of melatonin alleviates harmful side effects of chemotherapy-induced oxidative damage, aiding in decreasing therapeutic toxicities. The review concisely explains the many mechanisms by which melatonin targets osteosarcoma, as evidenced by significant results from several in vitro and animal models. Nevertheless, if further explored, human trials remain a challenge that could shed light and support its utility as an adjunctive therapeutic modality for treating osteosarcoma.

Neutrophil extracellular traps promote intestinal barrier dysfunction by regulating macrophage polarization during trauma/hemorrhagic shock via the TGF-β signaling pathway

The mechanism by which neutrophil extracellular traps (NETs) may cause intestinal barrier dysfunction in response to trauma/hemorrhagic shock (T/HS) remains unclear. In this study, the roles and mechanisms of NETs in macrophage polarization were examined to determine whether this process plays a role in tissue damage associated with T/HS. Rat models of T/HS and macrophage polarization were developed and the levels of NETs formation in the intestinal tissue of T/HS rats were assessed. NET formation was inhibited in models of T/HS to examine the effect on intestinal inflammation and barrier injury. The proportions of pro-inflammatory and anti-inflammatory macrophages in the damaged intestinal tissues were measured. Finally, high-throughput sequencing was performed to investigate the underlying mechanisms involved in this process. The study revealed that the level of NETs formation was increased and that inhibition of NETs formation alleviated the intestinal inflammation and barrier injury. Moreover, the number of pro-inflammatory macrophages increased and the number of anti-inflammatory macrophages decreased. RNA sequencing analysis indicated that NETs formation decreased the expression of transforming growth factor-beta receptor 2 (TGFBR2), bioinformatic analyses revealed that TGFBR2 was significantly enriched in the transforming growth factor-beta (TGF-β) signaling pathway. Verification experiments showed that NETs impeded macrophage differentiation into the anti-inflammatory/M2 phenotype and inhibited TGFBR2 and TGF-β expression in macrophages. However, treatment with DNase I and overexpression of TGFBR2, and inhibition of TGF-β promoted and prevented this process, respectively. NETs may regulate the macrophage polarization process by promoting intestinal barrier dysfunction in T/HS rats through the TGFBR2-mediated TGF-β signaling pathway.

Melatonin and bone-related diseases: an updated mechanistic overview of current evidence and future prospects

PURPOSE

Bone diseases account for an enormous cost burden on health systems. Bone disorders are considered as age-dependent diseases. The aging of world population has encouraged scientists to further explore the most effective preventive modalities and therapeutic strategies to overcome and reduce the high cost of bone disorders. Herein, we review the current evidence of melatonin's therapeutic effects on bone-related diseases.

METHODS

This review summarized evidences from in vitro, in vivo, and clinical studies regarding the effects of melatonin on bone-related diseases, with a focus on the molecular mechanisms. Electronically, Scopus and MEDLINE®/PubMed databases were searched for articles published on melatonin and bone-related diseases from inception to June 2023.

RESULTS

The findings demonstrated that melatonin has beneficial effect in bone- and cartilage-related disorders such as osteoporosis, bone fracture healing, osteoarthritis, and rheumatoid arthritis, in addition to the control of sleep and circadian rhythms.

CONCLUSION

A number of animal and clinical studies have indicated that various biological effects of melatonin may suggest this molecule as an effective therapeutic agent for controlling, diminishing, or suppressing bone-related disorders. Therefore, further clinical studies are required to clarify whether melatonin can be effective in patients with bone-related diseases.

Melatonin acts synergistically with pazopanib against renal cell carcinoma cells through p38 mitogen-activated protein kinase-mediated mitochondrial and autophagic apoptosis

BACKGROUND

Mounting evidence indicates that melatonin has possible activity against different tumors. Pazopanib is an anticancer drug used to treat renal cell carcinoma (RCC). This study tested the anticancer activity of melatonin combined with pazopanib on RCC cells and explored the underlying mechanistic pathways of its action.

METHODS

The 786-O and A-498 human RCC cell lines were used as cell models. Cell viability and tumorigenesis were detected with the MTT and colony formation assays, respectively. Apoptosis and autophagy were assessed using TUNEL, annexin V/propidium iodide, and acridine orange staining with flow cytometry. The expression of cellular signaling proteins was investigated with western blotting. The in vivo growth of tumors derived from RCC cells was evaluated using a xenograft mouse model.

RESULTS

Together, melatonin and pazopanib reduced cell viability and colony formation and promoted the apoptosis of RCC cells. Furthermore, the combination of melatonin and pazopanib triggered more mitochondrial, caspase-mediated, and LC3-II-mediated autophagic apoptosis than melatonin or pazopanib alone. The combination also induced higher activation of the p38 mitogen-activated protein kinase (p38MAPK) in the promotion of autophagy and apoptosis by RCC cells than melatonin or pazopanib alone. Finally, tumor xenograft experiments confirmed that melatonin and pazopanib cooperatively inhibited RCC growth in vivo and predicted a possible interaction between melatonin/pazopanib and LC3-II.

CONCLUSION

The combination of melatonin and pazopanib inhibits the growth of RCC cells by inducing p38MAPK-mediated mitochondrial and autophagic apoptosis. Therefore, melatonin might be a potential adjuvant that could act synergistically with pazopanib for RCC treatment.

Connection of Cancer Exosomal LncRNAs, Sponging miRNAs, and Exosomal Processing and Their Potential Modulation by Natural Products

Cancerous exosomes contain diverse biomolecules that regulate cancer progression. Modulating exosome biogenesis with clinical drugs has become an effective strategy for cancer therapy. Suppressing exosomal processing (assembly and secretion) may block exosomal function to reduce the proliferation of cancer cells. However, the information on natural products that modulate cancer exosomes lacks systemic organization, particularly for exosomal long noncoding RNAs (lncRNAs). There is a gap in the connection between exosomal lncRNAs and exosomal processing. This review introduces the database (LncTarD) to explore the potential of exosomal lncRNAs and their sponging miRNAs. The names of sponging miRNAs were transferred to the database (miRDB) for the target prediction of exosomal processing genes. Moreover, the impacts of lncRNAs, sponging miRNAs, and exosomal processing on the tumor microenvironment (TME) and natural-product-modulating anticancer effects were then retrieved and organized. This review sheds light on the functions of exosomal lncRNAs, sponging miRNAs, and exosomal processing in anticancer processes. It also provides future directions for the application of natural products when regulating cancerous exosomal lncRNAs.

Emerging role of long non-coding RNA JPX in malignant processes and potential applications in cancers

ABSTRACT

Long non-coding RNAs (lncRNAs) reportedly function as important modulators of gene regulation and malignant processes in the development of human cancers. The lncRNA JPX is a novel molecular switch for X chromosome inactivation and differentially expressed JPX has exhibited certain clinical correlations in several cancers. Notably, JPX participates in cancer growth, metastasis, and chemoresistance, by acting as a competing endogenous RNA for microRNA, interacting with proteins, and regulating some specific signaling pathways. Moreover, JPX may serve as a potential biomarker and therapeutic target for the diagnosis, prognosis, and treatment of cancer. The present article summarizes our current understanding of the structure, expression, and function of JPX in malignant cancer processes and discusses its molecular mechanisms and potential applications in cancer biology and medicine.

The Effects of circ_000558/miR-1225-5p/ARL4C on Regulating the Proliferation of Renal Cell Carcinoma Cells

Renal cell carcinoma (RCC) is one of the top ten tumors over the world. RCC is not sensitive to radiotherapy and chemotherapy. Therefore, it is necessary to find new targets for the treatment. CircRNAs are a special type of noncoding RNAs, which play important roles in many types of cancer. In this study, we found circ_000558 was upregulated in RCC cells, and it elevated the proliferation ability of RCC cells. The relationship between miR-1225-5p and circ_000558 or ARL4C was predicted via circBank and circular RNA interactome and confirmed by dual-luciferase reporter assay. Then, the effects of circ_000558/miR-1225-5p/ARL4C on RCC cell proliferation and apoptosis were assessed by CCK-8 assay. The results revealed that the knockdown of ARL4C significantly reduced RCC cell proliferation and overexpression of circ_000558 could significantly induce RCC cell proliferation after miR-1225-5p treatment further promoted the inhibitory ability of ARL4C knockdown. Overall, our study suggested that circ_000558/miR-1225-5p/ARL4C network was related to the RCC cell proliferation. This finding could provide new targets for the treatment and prognosis of RCC.

miR-135a inhibits the proliferation of HBV-infected hepatocellular carcinoma cells by targeting HOXA10

Background

The incidence of hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV) is extremely high. MicroRNAs (miRNAs) are a type of endogenous non-coding small RNA with novel molecular therapeutic mechanisms that plays an important role in the occurrence and development of cancers. This study aimed to explore the regulation mechanism of miR-135a and HOXA10 in the proliferation, invasion, and apoptosis of HCC cells.

Methods

Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis was used to detect the expression level of miR-135a. Overexpression of miR-135a was used to measure the roles of miR-135a in the proliferation, invasion, and apoptosis of HCC cells. A dual luciferase experiment was performed to assess the relationship between HOXA10 and miR-135a. Western blot was applied to observe the protein levels of p-p38, p-ERK, and p-JNK.

Results

The expression levels of miR-135a were significantly decreased in HCC tissues and cells. Overexpression of miR-135a inhibited the proliferation and invasion but promoted the apoptosis of HCC cells. Importantly, our results confirmed that HOXA10 was a direct target of miR-135a. Under HBV infection, silencing of HOXA10 significantly blocked the proliferation and invasion and promoted the apoptosis of HCC cells. In addition, miR-135a/HOXA10 regulated the expressions of p-p38, p-ERK, and p-JNK through the miR-135a/HOXA10 axis, thereby inhibiting the activation of the MAPK pathway.

Conclusions

HBV promoted the proliferation and invasion, and inhibited the apoptosis of HCC cells by regulating the miR-135a/HOXA10 pathway. These findings provide a theoretical basis for improving the treatment of HBV-infected HCC patients.

Interactions of melatonin with various signaling pathways: implications for cancer therapy

Melatonin is a neuro-hormone with conserved roles in evolution. Initially synthetized as an antioxidant molecule, it has gained prominence as a key molecule in the regulation of the circadian rhythm. Melatonin exerts its effect by binding to cytoplasmic and intra-nuclear receptors, and is able to regulate the expression of key mediators of different signaling pathways. This ability has led scholars to investigate the role of melatonin in reversing the process of carcinogenesis, a process in which many signaling pathways are involved, and regulating these pathways may be of clinical significance. In this review, the role of melatonin in regulating multiple signaling pathways with important roles in cancer progression is discussed, and evidence regarding the beneficence of targeting malignancies with this approach is presented.

Modulation of immunosuppressive cells and noncoding RNAs as immunotherapy in osteosarcoma

The most common bone cancer is osteosarcoma (OS), which mostly affects children and teenagers. Early surgical resection combined with chemotherapy significantly improves the prognosis of patients with OS. Existing chemotherapies have poor efficacy in individuals with distant metastases or inoperable resection, and these patients may respond better to novel immunotherapies. Immune escape, which is mediated by immunosuppressive cells in the tumour microenvironment (TME), is a major cause of poor OS prognosis and a primary target of immunotherapy. Myeloid-derived suppressor cells, regulatory T cells, and tumour-associated macrophages are the main immunosuppressor cells, which can regulate tumorigenesis and growth on a variety of levels through the interaction in the TME. The proliferation, migration, invasion, and epithelial-mesenchymal transition of OS cells can all be impacted by the expression of non-coding RNAs (ncRNAs), which can also influence how immunosuppressive cells work and support immune suppression in TME. Interferon, checkpoint inhibitors, cancer vaccines, and engineered chimeric antigen receptor (CAR-T) T cells for OS have all been developed using information from studies on the metabolic properties of immunosuppressive cells in TME and ncRNAs in OS cells. This review summarizes the regulatory effect of ncRNAs on OS cells as well as the metabolic heterogeneity of immunosuppressive cells in the context of OS immunotherapies.

Knockdown of lncRNA HOXD-AS2 Improves the Prognosis of Glioma Patients by Inhibiting the Proliferation and Migration of Glioma Cells

Objective

Increasing studies reported that long noncoding RNAs are involved in regulating glioma progression. However, the specific roles and mechanisms of lncRNAs in glioma remain unclear. Here, we sought to explore the functions of HOXD-AS2 in glioma progression.

Methods

Gene expressions of lncRNAs in 5 normal brain tissue specimens and 5 glioblastoma tissue specimens were detected by gene expression profile chip technology. Bioinformatic analysis was performed to see whether differential expression of lncRNAs played any significant role in glioma occurrence and progression. The relationship between HOXD-AS2 level and clinical prognosis of the patients was analyzed. HOXD-AS2 was specifically interfered with by siRNA technology to observe its effects on U251 cell growth, proliferation, apoptosis, and invasion.

Results

The expression level of HOXD-AS2 gene in glioma was significantly higher than that in the normal brain tissue, which was related to the tumor grade. The level of HOXD-AS2 gene in patients with high-grade glioma was higher than that in patients with low-grade glioma. High expression of HOXD-AS2 gene was a risk factor for poor prognosis of glioma patients. Knocking down the expression of HOXD-AS2 in glioma cell line U251 arrested the cell cycle and reduced the cell proliferation. Furthermore, it could significantly reduce the migration ability of the cells but had no significant effect on the invasion.

Conclusion

HOXD-AS2 is an oncogenic lncRNA associated with the poor prognosis of glioma. Knockdown of HOXD-AS2 may reduce the growth of glioma, which may provide a new avenue for treatment.

Molecular hallmarks of long non-coding RNAs in aging and its significant effect on aging-associated diseases

Aging is linked to the deterioration of many physical and cognitive abilities and is the leading risk factor for Alzheimer's disease. The growing aging population is a significant healthcare problem globally that researchers must investigate to better understand the underlying aging processes. Advances in microarrays and sequencing techniques have resulted in deeper analyses of diverse essential genomes (e.g., mouse, human, and rat) and their corresponding cell types, their organ-specific transcriptomes, and the tissue involved in aging. Traditional gene controllers such as DNA- and RNA-binding proteins significantly influence such programs, causing the need to sort out long non-coding RNAs, a new class of powerful gene regulatory elements. However, their functional significance in the aging process and senescence has yet to be investigated and identified. Several recent researchers have associated the initiation and development of senescence and aging in mammals with several well-reported and novel long non-coding RNAs. In this review article, we identified and analyzed the evolving functions of long non-coding RNAs in cellular processes, including cellular senescence, aging, and age-related pathogenesis, which are the major hallmarks of long non-coding RNAs in aging.

The role of lncRNA just proximal to XIST (JPX) in human disease phenotypes and RNA methylation: The novel biomarker and therapeutic target potential

Increasing evidence suggests that long non-coding RNAs (lncRNAs) are closely related to the initialization and development of human diseases. lncRNA just proximal to XIST (JPX), as a newly identified lncRNA, has been reported to be aberrantly expressed and associated with pathophysiological traits in numerous diseases, particularly cancers. More importantly, JPX has been proven to play important roles in various biological functions, including cell proliferation, migration, invasion, apoptosis, chemoresistance, and differentiation. In addition, we discuss the diverse molecular mechanisms and correlation with RNA methylation of JPX in several cancers. In this Review, we summarize current studies on JPX's roles in diseases and its potential application as a biomarker for both diagnoses and prognoses and a therapeutic target in human diseases.

A Noval Established Cuproptosis-Associated LncRNA Signature for Prognosis Prediction in Primary Hepatic Carcinoma

The copper ion content in the body maintains homeostasis, and when dysregulated, it can produce cytotoxicity and induce cell death through a variety of pathways. Cuproptosis refers to copper ions combining directly with acylated molecules, leading to the accumulation of oligomerization of lipoylated protein and subsequent downregulation of iron-sulfur cluster proteins; this induces proteotoxic stress and cell death. This study on the relationship between cuproptosis-related lncRNAs (CRLns) and the prognosis of primary hepatic carcinoma (PHC) has important clinical guiding significance for the diagnosis and treatment of PHC. Prognosis-related CRLRs were identified via rank-sum tests, correlational analyses, and univariate Cox regression, and a CRLR risk-scoring model (CRLRSM) was constructed using LASSO Cox regression. Patients were divided into high-risk and low-risk groups based on the median CRLRSM scores. Variance analysis for cuproptosis-related genes, gene set enrichment analysis, and correlational analysis for risk and immunity were performed using boxplots. Quantitative polymerase chain reactions were used to verify the CRLR levels in PHC cell lines. The study results showed that patients in the CRLRSM high-risk group had worse survival rates than those in the low-risk group. The PHC stage and risk score were independent prognostic factors for hepatocellular carcinoma. There were 7 CRLRs (MIR210HG, AC099850.3, AL031985.3, AC012073.1, MKLN1-AS, KDM4A-AS1, and PLBD1-AS1) associated with PHC prognosis, primarily through cellular metabolism, growth, proliferation, apoptosis, and immunity. In conclusion, the overexpression of 7 CRLRs in patients with PHC indicates a poor prognosis.

Loureirin A Exerts Antikeloid Activity by Antagonizing the TGF-β1/Smad Signalling Pathway

It has been recently shown that loureirin A (LA), a major active component of resina draconis, might be effective in the prevention and treatment of liver fibrosis. We examined whether LA could inhibit the formation of keloids. To investigate the pharmacological effects of loureirin A on keloid formation and the underlying mechanisms. CellTiter-Blue viability assays were used to examine the proliferation of keloid fibroblasts (KFs) that were treated with LA. Fibroblast migration was evaluated using a cell migration assay. Immunofluorescence staining was used to measure the expression of α-SMA in KFs. RT-qPCR was used to evaluate the mRNA expression of Col-I, Col-III, α-SMA, Bax, and Caspase-3, while Western blotting was used to evaluate the protein expression of Col-I, Col-III, α-SMA, Bax, Caspase-3, p-Smad2, and p-Smad3. LA inhibited the proliferation of KFs and suppressed the migration and TGF-β1-induced myofibroblast differentiation of KFs. In addition, LA downregulated the mRNA and protein levels of Col-I, Col-III, and α-SMA while promoting the mRNA and protein levels of Bax and Caspase-3. Moreover, LA downregulated the protein levels of p-Smad2 and p-Smad3 in cultured TGF-β1-treated KFs ex vivo. These results show that LA has an antikeloid effect on KFs by suppressing the TGF-β1/Smad signalling pathway. Our findings suggest that LA may be a potential candidate drug for the prevention and treatment of keloids.

Bioinformatics analysis of lncRNAs in the occurrence and development of osteosarcoma

BACKGROUND

Osteosarcoma (OS) is a disease with high mortality in children and adolescents, and metastasis is one of its important clinical features. However, the molecular mechanism of OS occurrence is not completely clear. Thus, we screened potential biomarkers of OS and analyze their prognostic value.

METHODS

The Cancer Genome Atlas (TCGA) datasets were used to analyze the differential lncRNAs in patients with OS of different immune score and the lncRNAs expressed by immune cells. Cox regression was used to develop the prognosis prediction model and specify the prognosis outcomes. Risk-proportional regression model was constructed, and the samples were divided into high and low groups based on the risk scores for the survival analysis. The areas under the receiver operating characteristic (ROC) curve were calculated and the risk-score model was verified. Finally, using 4 gene sets (comprising chemokines, immune checkpoint blockades, immune activity-related genes, and immune cells), and 4 analysis tools (CIBERSORT, TIMER, XCELL and MCP) to evaluated tumor immune infiltration.

RESULTS

Twenty-nine long non-coding ribonucleic acids (lncRNAs) were obtained from the intersection of the screened lncRNAs. Caspase recruitment domain-containing protein 8-antisense RNA 1 (CARD8-AS1), lncRNA five prime to Xist (FTX), KAT8 regulatory NSL complex unit 1-antisense RNA 1 (KANSL1-AS1), Neuroplastin Intronic Transcript 1 (NPTN-IT1), oligodendrocyte maturation-associated long intervening non-coding RNA (OLMALINC) and RPARP Antisense RNA 1 (RPARP-AS1) were found to be correlated with survival. Univariate and multivariate regression analysis showed risk score [HR (hazard ratio) 3.5, P value 0.0043; HR 3.7, P value 0.0033] and metastasis (HR 4.7, P value 6.60E-05; HR 4.8, P value 8.36E-05) were the key factors of patients with OS. The areas under curves (AUCs) of the 1-, 3-, and 5-year ROC curves of the prognostic model were 0.715, 0.729, and 0.771. The low-risk patients tended to have a high abundance of immune cells.

CONCLUSIONS

This study showed that a risk score based on 6 lncRNAs has potential value in the prognosis of OS, and patients with low-risk scores have high immune cell infiltration and good prognosis. This study may enrich understandings of underlying mechanisms related to the occurrence and development of OS.

Melatonin Increases the Sensitivity of Osteosarcoma Cells to Chemotherapy Drug Cisplatin

Chemotherapy, which is one of the common treatments for osteosarcoma (OS), has many side effects and in some cases has low effectiveness due to chemoresistance, hence it is vital to study new therapies for OS. In this regard, we combined melatonin with cisplatin and evaluate their effect on MG63 OS cells. Since melatonin has anti-cancer properties, we hypothesized that its combination with cisplatin could increase the effectiveness of cisplatin. Firstly, MTT assay was used to evaluate the cell viability and cytotoxicity of cisplatin on MG63 cells and the results showed that melatonin in combination with cisplatin increases the sensitivity of MG63 cells to cisplatin. In addition, qRT-PCR results showed that the expressions of miR-181 and P53, CYLD, CBX7 and BCL2 genes change in MG63 cells after treatment with the combination of cisplatin and melatonin, so that the expression of P53, CYLD and CBX7 increased and the expression of BCL2 and miR-181b decreases significantly. Furthermore, analysis of Annexin V/FITC assay data revealed that the rate of apoptosis in MG63 OS cell line remarkably promoted after treated with cisplatin and melatonin combination. As a result, our findings show that melatonin in combination with cisplatin increases the effectiveness of cisplatin in osteosarcoma cells and this study provides a new therapeutic approach for OS.

Identification of Implications of Angiogenesis and m6A Modification on Immunosuppression and Therapeutic Sensitivity in Low-Grade Glioma by Network Computational Analysis of Subtypes and Signatures

Angiogenesis is a complex process in the immunosuppressed low-grade gliomas (LGG) microenvironment and is regulated by multiple factors. N⁶-methyladenosine (m6A), modified by the m6A modification regulators (“writers” “readers” and “erasers”), can drive LGG formation. In the hypoxic environment of intracranial tumor immune microenvironment (TIME), m6A modifications in glioma stem cells are predominantly distributed around neovascularization and synergize with complex perivascular pathological ecology to mediate the immunosuppressive phenotype of TIME. The exact mechanism of this phenomenon remains unknown. Herein, we elucidated the relevance of the angiogenesis-related genes (ARGs) and m6A regulators (MAGs) and their influencing mechanism from a macro perspective. Based on the expression pattern of MAGs, we divided patients with LGG into two robust categories via consensus clustering, and further annotated the malignant related mechanisms and corresponding targeted agents. The two subgroups (CL1, CL2) demonstrated a significant correlation with prognosis and clinical-pathology features. Moreover, WGCNA has also uncovered the hub genes and related mechanisms of MAGs affecting clinical characters. Clustering analysis revealed a synergistic promoting effect of M6A and angiogenesis on immunosuppression. Based on the expression patterns of MAGs, we established a high-performance gene-signature (MASig). MASig revealed somatic mutational mechanisms by which MAGs affect the sensitivity to treatment in LGG patients. In conclusion, the MAGs were critical participants in the malignant process of LGG, with a vital potential in the prognosis stratification, prediction of outcome, and therapeutic sensitivity of LGG. Findings based on these strategies may facilitate the development of objective diagnosis and treatment systems to quantify patient survival and other outcomes, and in some cases, to identify potential unexplored targeted therapies.

Use of Melatonin in Cancer Treatment: Where Are We?

Cancer represents a large group of diseases accounting for nearly 10 million deaths each year. Various treatment strategies, including surgical resection combined with chemotherapy, radiotherapy, and immunotherapy, have been applied for cancer treatment. However, the outcomes remain largely unsatisfying. Melatonin, as an endogenous hormone, is associated with the circadian rhythm moderation. Many physiological functions of melatonin besides sleep–wake cycle control have been identified, such as antioxidant, immunomodulation, and anti-inflammation. In recent years, an increasing number of studies have described the anticancer effects of melatonin. This has drawn our attention to the potential usage of melatonin for cancer treatment in the clinical setting, although huge obstacles still exist before its wide clinical administration is accepted. The exact mechanisms behind its anticancer effects remain unclear, and the specific characters impede its in vivo investigation. In this review, we will summarize the latest advances in melatonin studies, including its chemical properties, the possible mechanisms for its anticancer effects, and the ongoing clinical trials. Importantly, challenges for the clinical application of melatonin will be discussed, accompanied with our perspectives on its future development. Finally, obstacles and perspectives of using melatonin for cancer treatment will be proposed. The present article will provide a comprehensive foundation for applying melatonin as a preventive and therapeutic agent for cancer treatment.

3'-daidzein sulfonate protects myocardial cells from hypoxic-ischemic injury via the NRF2/HO-1 signaling pathway

Background

Myocardial infarction (MI) has a high mortality and disability rate and greatly affects human health. This study sought to explore the therapeutic effect and molecular mechanism of 3'-daidzein sulfonate (DSS) on MI.

Methods

A rat MI model was established and low and high doses of DSS were administered to the rats. An in vitro oxygen glucose deprivation model was used to verify the treatment role and mechanism of DSS. The establishment of the rat MI model was confirmed by electrocardiogram. The tissue changes were detected by HE, Masson’s trichrome, TUNEL and TTC staining. Cell viability was detected by CCK-8. The viable and dead cells were detected by Calcein-AM/PI. Apoptotic cells, ROS and JC-1 were detected by flow cytometry apoptosis. The level of proteins was detected by western blotting. MDA, SOD and GSH were detected by ELISA.

Results

The results of Hematoxylin and eosin, TUNEL, and Masson staining showed that the myocardial tissue of the MI group was repaired by DSS. The serum levels of cardiac troponin I (CTnI), lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), and malondialdehyde (MDA) were decreased by DSS, while the serum levels of superoxide dismutase and glutathione were promoted by DSS. The treatment of DSS activated the Nuclear Factor Erythroid 2-Related Factor 2 (NRF-2)/Heme Oxygenase 1 (HO-1) pathway and inhibited the caspase-3 apoptosis pathway. The in vitro experiment showed that DSS greatly restored cell viability and reduced cell apoptosis. DSS also greatly inhibited mitochondrial membrane potential depolarization, reactive oxygen species production, and oxidative stress. The application of the NRF-2 inhibitor, C₂₉H₂₅N₃O₄S (ML385), greatly inhibited the treatment role of DSS and the NRF-2/HO-1 pathway, and activated the caspase-3 apoptosis pathway.

Conclusions

In conclusion, this study first identified the beneficial role of DSS in MI. DSS protected myocardial cells by activating the NRF-2/HO-1 pathway and inhibiting cell apoptosis. DSS could be used as a novel drug in the treatment of MI.

Anticancer effects of melatonin via regulating lncRNA JPX-Wnt/β-catenin signalling pathway in human osteosarcoma cells

Osteosarcoma (OS) is a type of malignant primary bone cancer, which is highly aggressive and occurs more commonly in children and adolescents. Thus, novel potential drugs and therapeutic methods are urgently needed. In the present study, we aimed to elucidate the effects and mechanism of melatonin on OS cells to provide a potential treatment strategy for OS. The cell survival rate, cell viability, proliferation, migration, invasion and metastasis were examined by trypan blue assay, MTT, colony formation, wound healing, transwell invasion and attachment/detachment assay, respectively. The expression of relevant lncRNAs in OS cells was determined by real-time qPCR analysis. The functional roles of lncRNA JPX in OS cells were further examined by gain and loss of function assays. The protein expression was measured by western blot assay. Melatonin inhibited the cell viability, proliferation, migration, invasion and metastasis of OS cells (Saos-2, MG63 and U2OS) in a dose-dependent manner. Melatonin treatment significantly downregulated the expression of lncRNA JPX in Saos-2, MG63 and U2OS cells. Overexpression of lncRNA JPX into OS cell lines elevated the cell viability and proliferation, which was accompanied by the increased metastasis. We also found that melatonin inhibited the OS progression by suppressing the expression of lncRNA JPX via regulating the Wnt/β-catenin pathway. Our results suggested that melatonin inhibited the biological functions of OS cells by repressing the expression of lncRNA JPX through regulating the Wnt/β-catenin signalling pathway, which indicated that melatonin might be applied as a potentially useful and effective natural agent in the treatment of OS.