Icarisid II inhibits the proliferation of human osteosarcoma cells by inducing apoptosis and cell cycle arrest

Synthesis, evaluation of anti-breast cancer activity in vitro of ICS II derivatives and summary of the structure-activity relationship

A series of Icariside II (ICS II) derivatives were synthesized, and their structure-activity relationships (SARs) were studied in this paper. The in vitro antitumor activities towards human breast cancer cell lines (MCF-7) were evaluated by Cell Counting Kit-8 (CCK-8 kit). Preliminary results showed that, compared with ICS II, most of the derivatives displayed good micromole level activities. Among the series of derivatives, the S27, which totally acetylated hydroxyl of ICS II, possessed highest cytotoxicity, with IC₅₀ values of 0.70 ± 0.08 μM. Furthermore, compound S27 showed better selectivity than ICS II for cancer cells over normal cells. Our findings indicate that compound S27 may be a promising anticancer lead candidate drug.

Identification and verification of m7G-Related genes as biomarkers for prognosis of sarcoma

Background: Increasing evidence indicates a crucial role for N7-methylguanosine (m7G) methylation modification in human disease development, particularly cancer, and aberrant m7G levels are closely associated with tumorigenesis and progression via regulation of the expression of multiple oncogenes and tumor suppressor genes. However, the role of m7G in sarcomas (SARC) has not been adequately evaluated. Materials and methods: Transcriptome and clinical data were gathered from the TCGA database for this study. Normal and SARC groups were compared for the expression of m7G-related genes (m7GRGs). The expression of m7GRGs was verified using real-time quantitative PCR (RT-qPCR) in SARC cell lines. Then, differentially expressed genes (DEGs) were identified between high and low m7GRGs expression groups in SARC samples, and GO enrichment and KEGG pathways were evaluated. Next, prognostic values of m7GRGs were evaluated by Cox regression analysis. Subsequently, a prognostic model was constructed using m7GRGs with good prognostic values by Lasso regression analysis. Besides, the relationships between prognostic m7GRGs and immune infiltration, clinical features, cuproptosis-related genes, and antitumor drugs were investigated in patients with SARC. Finally, a ceRNA regulatory network based on m7GRGs was constructed. Results: The expression of ten m7GRGs was higher in the SARC group than in the control group. DEGs across groups with high and low m7GRGs expression were enriched for adhesion sites and cGMP-PKG. Besides, we constructed a prognostic model that consists of EIF4A1, EIF4G3, NCBP1, and WDR4 m7GRGs for predicting the survival likelihood of sarcoma patients. And the elevated expression of these four prognostic m7GRGs was substantially associated with poor prognosis and elevated expression in SARC cell lines. Moreover, we discovered that these four m7GRGs expressions were negatively correlated with CD4⁺ T cell levels, dendritic cell level and tumor purity, and positively correlated with tumor mutational burden, microsatellite instability, drug sensitivity and cuproptosis-related genes in patients with sarcomas. Then, a triple regulatory network of mRNA, miRNA, and lncRNA was established. Conclusion: The current study identified EIF4A1, EIF4G3, NCBP1, and WDR4 as prognostic genes for SARC that are associated with m7G.These findings extend our knowledge of m7G methylation in SARC and may guide the development of innovative treatment options.

The role of dietary polyphenols in osteosarcoma: A possible clue about the molecular mechanisms involved in a process that is just in its infancy

Osteosarcoma (OS) is a primary malignant bone tumor mainly affecting children, teenagers and young adults, being associated with early metastasis and poor prognosis. The beneficial effects of polyphenols have been investigated in different areas, including their potential to fight OS. Polyphenols are believed to reduce morbidity and/or slow down the development of cancer. This review aimed to assess the effect of polyphenols in OS and investigate their molecular mechanisms. It was observed that the broad spectrum of health-promoting properties of plant polyphenols in OS occurs mainly due to modulation of reactive oxygen species, anti-inflammatory activity, anti-angiogenesis, apoptosis inducer, inhibition of invasion and metastasis. However, it is worth mentioning that although the promising effects of polyphenols in the fight against OS, most of the studies have been performed using in vitro and in vivo animal models. Therefore, studies in humans are needed to validate the effectiveness of polyphenols in OS treatment. PRACTICAL APPLICATIONS: Polyphenols are widely used for various diseases, however, until now, their real role in the treatment of osteosarcoma remains unknown. This review provides a broad spectrum of research conducted with polyphenols and their potential as adjuvant therapy in the treatment of osteosarcoma. However, prior to their clinical application for osteosarcoma treatment, there is a need to isolate and identify specific polyphenolic compounds with high antitumor activity, increase their oral bioavailability, and to investigate their interactions with chemotherapeutic drugs being used in clinical practice.

3',4'-Dihydroxyflavonol Modulates the Cell Cycle in Cancer Cells: Implication as a Potential Combination Drug in Osteosarcoma

New agents are demanded to increase the therapeutic options for osteosarcoma (OS). Although OS is the most common bone cancer in children and adolescents, it is considered a rare disorder. Therefore, finding adjuvant drugs has potential to advance therapy for this disease. In this study, 3′,4′-dihydroxyflavonol (DiOHF) was investigated to assess the effects in OS cellular models in combination with doxorubicin (Dox). MG-63 and U2OS human OS cells were exposed to DiOHF and Dox and tested for cell viability and growth. To elucidate the inhibitory effects of DiOHF, additional studies were conducted to assess apoptosis and cell cycle distribution, gene expression quantification of cell cycle regulators, and cytokinesis-block cytome assay to determine nuclear division rate. DiOHF decreased OS cell growth and viability in a concentration-dependent manner. Its combination with Dox enabled Dox dose reduction in both cell lines, with synergistic interactions in U2OS cells. Although no significant apoptotic effects were detected at low concentrations, cytostatic effects were demonstrated in both cell lines. Incubation with DiOHF altered cell cycle dynamics and resulted in differential cyclin and cyclin-dependent kinase expression. Overall, this study presents an antiproliferative action of DiOHF in OS combination therapy via modulation of the cell cycle and nuclear division.

Tanshinone IIA inhibits osteosarcoma growth through modulation of AMPK-Nrf2 signaling pathway

Tanshinone IIA (Tan IIA) is a member of the major lipophilic components extracted from the root of Salvia miltiorrhiza Bunge. Osteosarcomas are primary malignant tumors of bone. The aim of our study is to explore the role of Tan IIA in osteosarcomas survival, migration, and proliferation. MG63 osteosarcoma cell line was cultured in vitro and treated with different concentrations of Tan IIA. Then, ELISA, immunofluorescence, qPCR, western blots, and pathway analysis were conducted to verify whether Tan II modulated osteosarcoma survival, migration, and proliferation through the AMPK/Nrf2 signaling pathway. Our results indicated that Tan IIA dose-dependently inhibited MG63 osteosarcoma cell survival, migration, and proliferation. Mechanistically, Tan IIA reduced cell viability and inhibited the transcriptions of migratory factors. In addition, the number of proliferative MG63 osteosarcoma cell was also reduced by Tan IIA. Molecular investigations demonstrated that Tan IIA treatment caused a drop in the transcriptions and activities of AMPK and Nrf2. Interestingly, knockdown of AMPK and Nrf2 markedly attenuated MG63 osteosarcoma cell survival, migration, and proliferation. Altogether, our results indicate that Tan IIA could be used as an effective anticancer drug to control osteosarcoma proliferation through affecting its survival, migration, and proliferation.

Apoptotic Pathway as the Therapeutic Target for Anticancer Traditional Chinese Medicines

Cancer is a leading cause of morbidity and mortality worldwide. Apoptosis is a process of programmed cell death and it plays a vital role in human development and tissue homeostasis. Mounting evidence indicates that apoptosis is closely related to the survival of cancer and it has emerged as a key target for the discovery and development of novel anticancer drugs. Various studies indicate that targeting the apoptotic signaling pathway by anticancer drugs is an important mechanism in cancer therapy. Therefore, numerous novel anticancer agents have been discovered and developed from traditional Chinese medicines (TCMs) by targeting the cellular apoptotic pathway of cancer cells and shown clinically beneficial effects in cancer therapy. This review aims to provide a comprehensive discussion for the role, pharmacology, related biology, and possible mechanism(s) of a number of important anticancer TCMs and their derivatives mainly targeting the cellular apoptotic pathway. It may have important clinical implications in cancer therapy.

Vitamin C promotes the proliferation and effector functions of human γδ T cells

γδ T cells are of interest as effector cells for cellular immunotherapy due to their HLA-non-restricted lysis of many different tumor cell types. Potential applications include the adoptive transfer of in vitro-expanded γδ T cells. Therefore, it is important to optimize the culture conditions to enable maximal proliferative and functional activity. Vitamin C (L-ascorbic acid) is an essential vitamin with multiple effects on immune cells. It is a cofactor for several enzymes, has antioxidant activity, and is an epigenetic modifier. Here, we investigated the effects of vitamin C (VC) and its more stable derivative, L-ascorbic acid 2-phosphate (pVC), on the proliferation and effector function of human γδ T cells stimulated with zoledronate (ZOL) or synthetic phosphoantigens (pAgs). VC and pVC did not increase γδ T-cell expansion within ZOL- or pAg-stimulated PBMCs, but increased the proliferation of purified γδ T cells and 14-day-expanded γδ T-cell lines in response to γδ T-cell-specific pAgs. VC reduced the apoptosis of γδ T cells during primary stimulation. While pVC did not prevent activation-induced death of pAg-restimulated γδ T cells, it enhanced the cell cycle progression and cellular expansion. Furthermore, VC and pVC enhanced cytokine production during primary activation, as well as upon pAg restimulation of 14-day-expanded γδ T cells. VC and pVC also increased the oxidative respiration and glycolysis of γδ T cells, but stimulus-dependent differences were observed. The modulatory activity of VC and pVC might help to increase the efficacy of γδ T-cell expansion for adoptive immunotherapy.

Improved Pharmacokinetics of Icariin (ICA) within Formulation of PEG-PLLA/PDLA-PNIPAM Polymeric Micelles

Icariin (ICA) is a major flavonoid that contains the active compound Epimedii Folium. However, ICA’s pharmacokinetic characteristics remain unsatisfactory due to its low bioavailability, and hence limited drugability. In order to improve its pharmacokinetics and achieve prolonged blood circulation time, a novel polymeric micelle, made of the self-assembled micelle between poly (ethylene glycol)-poly (_L-lactic acid) (PEG-PLLA) and poly (_D-lactic acid)-poly(N-isopropylacrylamide) (PDLA-PNIPAM), was designed to encapsulate ICA. Our experimental results showed that this polymeric micelle formulation of ICA exhibited uniform nano-size distribution and high stability within 48 h. The new formulation also allowed sustained ICA release in an in vitro drug release study. Furthermore, in vivo experiments revealed that ICA bioavailability in the PEG-PLLA/PDLA-PNIPAM polymeric micelle formulation was significantly higher compared to ICA alone, or ICA in the traditional Pluronic F127 micelle formulation. Finally, we show that metabolite analysis confirmed that ICA within the PEG-PLLA/PDLA-PNIPAM polymeric micelle formulation provided better drug protection, reduced drug metabolites production, and decreased undesired first-pass effects. Overall, these data show that ICA within PEG-PLLA/PDLA-PNIPAM polymeric micelle formulation exhibit advantages, in terms of improved physicochemical properties, sustained release of ICA in vitro, and improved bioavailability of ICA in vivo, which represent a feasible approach for improving the drugability of pharmaceutical small molecules with low bioavailability or poor stability.

MicroRNA-17 promotes osteosarcoma cells proliferation and migration and inhibits apoptosis by regulating SASH1 expression

MicroRNAs (miRNAs) are abnormally expressed in numerous diseases, which are intimately associated with cell proliferation, migration and invasion. Recent study indicated that miR-17 may be involved in regulating osteosarcoma (OS) occurrence and development, but its function and mechanism have not been reported. In this study, quantitative real-time PCR (qRT-PCR) was used to measure the expression of miR-17, and Western blotting assay was performed to measure the expressions of SAM and SH3 domain containing 1 (SASH1), phosphoinoinositide-3 kinase (PI3K), protein kinase B (AKT), Caspase3, Bcl-2 gene family (Bcl-2, Bax) and matrix metalloprotein (MMP-2, MMP-9) in MG-63 cells. Luciferase reporter assay was conducted to confirm the target of SASH1 by miR-17. Cell proliferation, migration, invasion and apoptosis assay was performed to investigate the role of miR-17 in OS cells. We found that the expression of miR-17 was significantly up-regulated in OS cell lines. MiR-17 inhibitor inhibited the proliferation ability, and induced apoptosis of OS cells. Besides, miR-17 inhibitor prevented the migration and invasion of OS cells. Further, we identified that SASH1 was a target gene of miR-17. In addition, knockdown of miR-17 increased the protein expression of SASH1, and regulate related genes of cell proliferation, invasion and anti-apoptosis in the downstream of OS cells. These findings indicated that miR-17 was over-expressed and promoted cell proliferation, migration and inhibited cell apoptosis by targeting SASH1 in OS cells.

Circular RNAs hsa_circ_0032462, hsa_circ_0028173, hsa_circ_0005909 are predicted to promote CADM1 expression by functioning as miRNAs sponge in human osteosarcoma

BACKGROUND

Osteosarcoma (OS) is a primary malignant bone tumor with a high fatality rate. Many circRNAs have been proved to play important roles in the pathogenesis of some diseases. However, the occurrence of circRNAs in OS remains little known.

METHODS

The circular RNA (circRNA) expression file GSE96964 dataset, which included seven osteosarcoma cell lines and one control sample (osteoblast cell line), was downloaded from the Gene Expression Omnibus (GEO) database to explore the potential function of circRNAs in osteosarcoma by competing endogenous RNA (ceRNA) analysis. Three gene expression profiles of OS were downloaded from GEO database and then used for the pathway enrichment analysis, Venn analysis and protein-protein interaction (PPI) network analysis. Real-time qPCR validation and RNA interference were conducted to verify our prediction.

RESULTS

Differentially expressed circRNAs between OS and control, including 8 up-regulated and 102 down-regulated circRNAs, were generated and ceRNA analysis for 5 most up-regulated or 5 most down-regulated circRNAs in OS were then performed. The pathway enrichment analysis of gene expression profiles indicated differentially expressed genes (DEGs) of three gene profiles significantly enriched in cell cycle pathway, cell adhesion molecules (CAMs) pathway, oxidative phosphorylation pathway, cytokine-cytokine receptor interaction pathway, p53 signaling pathway and proteoglycans in cancer pathway, which were critical important pathways in the pathogenesis of OS. The Venn analysis showed that 2 (one is a pseudogene) up-regulated and 39 down-regulated DEGs were co-expressed in all three gene profiles. Then PPI networks of 41 co-expressed DEGs (up- and down-regulated DEGs) were constructed to predict their functions using the GeneMANIA. The expression levels of these related RNAs also matched our predictions really well.

CONCLUSION

Ultimately, we found cell adhesion molecule 1 (CADM1) gene was not only a co-expression mRNA of the three mRNA expression profiles of OS, but also are predicted to be regulated by hsa_circ_0032462, hsa_circ_0028173, hsa_circ_0005909 by functioning as miRNAs 'Sponge' in human osteosarcoma. These over-expressed circRNAs may result in the over expression of CADM1 which promote the development of OS. We envision this discovery of these important moleculars, incuding hsa_circ_0032462, hsa_circ_0028173, hsa_circ_0005909 and CADM1 may lead to further development of new concepts, thus allowing for more opportunities in diagnosis and therapy of OS.

Synthesis and Biological Evaluation of Novel Alkyl Amine Substituted Icariside II Derivatives as Potential Anticancer Agents

A series of novel alkyl amine-substituted icariside II (ICA II) derivatives were synthesized by Mannich reactions at the 6-C position (compounds 4a–d) and changing the carbon chain length at the 7-OH position (compounds 7a–h), and their in vitro antitumor activity towards human breast cancer lines (MCF-7 and MDA-MB-231) and human hepatoma cell lines (HepG2 and HCCLM3-LUC) were evaluated by the MTT assay. Compared with ICA II, most of the twelve derivatives showed good micromole level activity and a preliminary structure-activity relationship (SAR) for the anticancer activity was obtained. Compound 7g showed the most potent inhibitory activity for the four cancer cell lines (13.28 μM for HCCLM3-LUC, 3.96 μM for HepG2, 2.44 μM for MCF-7 and 4.21 μM for MDA-MB-231), which was 2.94, 5.54, 12.56 and 7.72-fold stronger than that of ICA II. The preliminary SAR showed that the introduction of a alkyl amine substituent at 6-C was not favorable for the anticancer activity, while most of the 7-O-alkylamino derivatives exhibited good antitumor activity and the anticancer activity 7-O-alkylamino derivatives were influenced by the alkyl chain length and the different terminal amine substituents. Furthermore, the effects of compound 7g on apoptosis and cell cycle of MCF-7 cells were further investigated, which showed that compound 7g triggered apoptosis and arrested the cell cycle at the G0/G1 phase in MCF-7 cells. Our findings indicate that compound 7g may be a promising anticancer drug candidate lead.

Anti-Cancer Activity of Lobaric Acid and Lobarstin Extracted from the Antarctic Lichen Stereocaulon alpnum

Lobaric acid and lobarstin, secondary metabolites derived from the antarctic lichen Stereocaulon alpnum, exert various biological activities, including antitumor, anti-proliferation, anti-inflammation, and antioxidant activities. However, the underlying mechanisms of these effects have not yet been elucidated in human cervix adenocarcinoma and human colon carcinoma. In the present study, we evaluated the anticancer effects of lobaric acid and lobarstin on human cervix adenocarcinoma HeLa cells and colon carcinoma HCT116 cells. We show that the proliferation of Hela and HCT116 cells treated with lobaric acid and lobarstin significantly decreased in a dose- and time-dependent manner. Using flow cytometry analysis, we observed that the treatment with these compounds resulted in significant apoptosis in both cell lines, following cell cycle perturbation and arrest in G2/M phase. Furthermore, using immunoblot analysis, we investigated the expression of cell cycle and apoptosis-related marker genes and found a significant downregulation of the apoptosis regulator B-cell lymphoma 2 (Bcl-2) and upregulation of the cleaved form of the poly (ADP-ribose) polymerase (PARP), a DNA repair and apoptosis regulator. These results suggest that lobaric acid and lobarstin could significantly inhibit cell proliferation through cell cycle arrest and induction of apoptosis via the mitochondrial apoptotic pathway in cervix adenocarcinoma and colon carcinoma cells. Taken together, our data suggests that lobaric acid and lobarstin might be novel agents for clinical treatment of cervix adenocarcinoma and colon carcinoma.