Saos-2 Cells Research Articles

Boldine Treatment Induces Cytotoxicity in Human Colorectal Carcinoma and Osteosarcoma Cells.

Introduction Cancer continues to be a significant health issue worldwide, with colorectal cancer (CRC) standing out as one of the most prevalent forms of cancer on a global scale. The lifetime risk of developing CRC is about one in 23 (4.3%) for men and one in 25 (4.0%) for women. Moreover, children and adolescents are frequently reported with osteosarcoma with a low five-year survival rate (69% and 67%, respectively). Aim The aim of the study was to analyze the cytotoxic effects of boldine against human CRC (HCT-116) and osteosarcoma cell lines (Saos-2). Materials and methods HCT-116 and Saos-2 cell lines were subjected to different concentrations of boldine treatment (5, 10, 20, 30, 40, and 50 μg/mL) and (10, 20, 40, 60, and 80 µg/mL), respectively, for 24 hours. The cytotoxicity was analyzed by MTT assay, AO/EBstaining, DCFH-DA assay, and scratch assay. Results The MTT assay, microscopic analysis, and staining showed that boldine had dose-dependent cytotoxic effects against HCT-116 and Saos-2 cell lines by inhibiting their proliferation, viability, and migration, and inducing ROS-mediated apoptosis. Conclusion The study concluded that boldine had a concentration-dependent cytotoxic effect on human CRC and osteosarcoma cell lines.

Evaluation of the Biological Effect of Non-UV-Activated Bergapten on Selected Human Tumor Cells and the Insight into the Molecular Mechanism of Its Action.

There is some evidence that non-photoactivated psoralens may be active against breast and colon tumor cells. Therefore, we evaluated the antiproliferative, proapoptotic, and anti-migrative effect of 5-methoxypsoralen (5-MOP) isolated from Peucedanum tauricum MB fruits in human colorectal adenocarcinoma (HT-29 and SW620), osteosarcoma (Saos-2 and HOS), and multiple myeloma (RPMI8226 and U266). Dose- and cell-line-dependent effects of 5-MOP on viability and proliferation were observed, with the strongest inhibitory effect against Saos-2 and a moderate effect against the HOS, HT-29, and SW620 cells. Multiple myeloma showed low sensitivity. The high viability of human normal cell cultures (HSF and hFOB) in a wide range of 5-MOP concentrations tested (6.25-100 µM) was confirmed. Moreover, the migration of treated Saos-2, SW620, and HT-29 cell lines was impaired, as indicated via a wound healing assay. Flow cytometry analysis conducted on Saos-2 cells revealed the ability of 5-MOP to block the cell cycle in the G2 phase and trigger apoptosis, which was accompanied by a loss of mitochondrial membrane potential, caspases (-9 and -3) activation, the altered expression of the Bax and Bcl-2 proteins, and decreased AKT phosphorylation. This is the first report evaluating the antiproliferative and antimigratory impact of non-UV-activated bergapten on the abovementioned (except for HT-29) tumor cells, which provides new data on the potential role of 5-MOP in inhibiting the growth of various types of therapeutic-resistant cancers.

Nelumbo nucifera Leaf Extract Induces Cytotoxicity in Osteosarcoma Saos-2 Cells.

Background Osteosarcoma is the eighth most common cancer and its prevalence in children makes it a global concern. Existing medications and treatments like high-dose methotrexate possess harmful side effects. Therefore, novel herbal drugs like Nelumbo nucifera are of utmost importance. Aim To analyze a novel anticancer herbal drug, Nelumbo nucifera leaf extractfor its cytotoxic potential against osteosarcoma. Materials and method Nelumbo nucifera leaf extract was prepared. Saos-2 Cells (human osteosarcoma cell line) were treated with Nelumbo nucifera leaf extract (25, 50, 75, 100, 125, and 150 µg/ml) for 24 hours which were then subjected to MTT assay, morphological analysis and DAPI staining. Results The results suggested that Nelumbo nucifera leaf extract had a concentration-dependent cytotoxic effect onSaos-2 cell line. The extract significantly reduced the number of viable cells, inhibited proliferation and induced morphological changes in Saos-2 cells. Conclusion Nelumbo nucifera has the potential to induce cytotoxicity against osteosarcoma cell lines and hence, this study provides a novel therapeutic regimen for the treatment of osteosarcoma.

Chemical characterization of the crude extract of Sauromatum venosum (voodoo lily) and docking study with 12-O-acetylingol 8-tiglate for cytotoxicity testing in SaOS2 (osteoblastic osteosarcoma cells).

The current study was carried out to investigate the anticancer potential of Sauromatum venosum (SV) tuber by gas chromatography with high-resolution mass spectrometry (GC-HRMS) analysis of ethanolic (eSV), hydroalcoholic (hSV), and aqueous extracts (wSV), and in silico study were performed to investigate the main targets of 12-O-acetylingol 8-tiglate by computational docking. The GC-HRMS analysis of three plant samples was carried out on a system equipped with a high-resolution mass spectrometer. The major compounds were identified in all crude extracts. Computation docking analysis was performed for the prediction of the main target of the cancer proliferation of active compound of the Sauromatum venosum tuber extract in cancer therapy. A total of 45 phytocompounds were detected including diterpenoids, esters of fatty acid, hydrocarbons, and alkanes in the tuber of SV. Among all the crude samples tested, eSV showed the lowest IC50 value treated with SaOS2 cells. 12-O-acetylingol 8-tiglate is one of the phytocompounds identified in eSV extract and has been found to exhibit cytotoxic effects against various cancer cells, as reported in the research. It shows the optimum binding affinity with -8.59kcal/mol binding energy with a molecular target protein TNF-α (PDB ID: 7PKA). The observed interactions strongly support the anticancer activity of 12-O-acetylingol 8-tiglate and its role in the medicinal efficacy of the plant. These findings highlight the potential of the compound as a valuable source for the development of a therapeutic agent aimed at combating cancer. However, it is important to note that additional in vitro and in vivo studies are required to validate these findings and establish the therapeutic potential.

Mutant p53 Gain-of-Function Induces Migration and Invasion through Overexpression of miR-182-5p in Cancer Cells.

The master-key TP53 gene is a tumor suppressor that is mutated in more than 50% of human cancers. Some p53 mutants lose their tumor suppressor activity and acquire new oncogenic functions, known as a gain of function (GOF). Recent studies have shown that p53 mutants can exert oncogenic effects through specific miRNAs. We identified the differentially expressed miRNA profiles of the three most frequent p53 mutants (p53R273C, p53R248Q, and p53R175H) after their transfection into the Saos-2 cell line (null p53) as compared with p53WT transfected cells. The associations between these miRNAs and the signaling pathways in which they might participate were identified with miRPath Software V3.0. QRT-PCR was employed to validate the miRNA profiles. We observed that p53 mutants have an overall negative effect on miRNA expression. In the global expression profile of the human miRNome regulated by the p53R273C mutant, 72 miRNAs were underexpressed and 35 overexpressed; in the p53R175H miRNAs profile, our results showed the downregulation of 93 and upregulation of 10 miRNAs; and in the miRNAs expression profile regulated by the p53R248Q mutant, we found 167 decreased and 6 increased miRNAs compared with p53WT. However, we found overexpression of some miRNAs, like miR-182-5p, in association with processes such as cell migration and invasion. In addition, we explored whether the induction of cell migration and invasion by the p53R48Q mutant was dependent on miR-182-5p because we found overexpression of miR-182-5p, which is associated with processes such as cell migration and invasion. Inhibition of mutant p53R248Q and miR-182-5p increased FOXF2-MTSS1 levels and decreased cell migration and invasion. In summary, our results suggest that p53 mutants increase the expression of miR-182-5p, and this miRNA is necessary for the p53R248Q mutant to induce cell migration and invasion in a cancer cell model.

In Vitro Characterization of Doped Bioglass 45S5/HAp Coatings Obtained by CoBlastTM Deposition

Bone replacement is one of the major medical procedures in the oral surgery field due to the progressive ageing population and to illness or trauma in younger age groups. The use of implants without biological activity and effective osseointegration increases the chances of implant failure. This work aims to improve the interaction between implants and bone by using Bioglass 45S5 (BG)/hydroxyapatite (HAp) mixtures, including copper-, zinc-, and cerium-doped BG, as well as co-doping by the mentioned metals, as coatings produced by the CoBlastTM technique. All coatings present a uniform coverage of the Ti-6Al-4V substrate. Furthermore, in vitro testing using human osteosarcoma Saos-2 cells indicated that BG/HAp coatings have no cytotoxic effect, and the used of doping agents did not alter cell adhesion, proliferation, or alkaline phosphatase (ALP) expression when compared to undoped coating. These results demonstrate that BG/HAp by CoBlastTM can be a solution to improve implants’ osseointegration.

Synthesis, characterization, and in vitro cytotoxic evaluation of hydroxyapatite submicron particles functionalized with 2-chlorobenzoylthiourea as a drug delivery system

In this study, hydroxyapatite (HAp) nanoparticles (NPs) were synthesized via hydrothermal synthesis method. The surfaces of HAp NPs were functionalized with (3-aminopropyl)triethoxysilane (APTES) and 2-chlorobenzoylthiourea (BT) to obtain HAp–APTES–BT NPs. The structural characterization of HAp submicron particles was made via FTIR and X-ray diffraction techniques. HAp–APTES and HAp–APTES–BT submicron particles were characterized via FTIR. The particle size of HAp submicron particles was determined to be 1281, 1484, and 1718 nm, and their zeta potentials were determined to be −3.38, −3.25, and −3.18. Zoledronic acid (ZA) was loaded onto the HAp–APTES–BT submicron particles under supercritical CO2 conditions (25 °C, 200 bar, 1 h). Drug release profiles of HAp–APTES–BT–ZA submicron particles were investigated in phosphate buffered saline solution (pH 7.4, 37 °C) for 72 h. The cytotoxic effects of HAp–APTES–BT–ZA submicron particles on Saos-2 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-diphenyl tetrazolium bromide test.

Eugenol: In Vitro and In Ovo Assessment to Explore Cytotoxic Effects on Osteosarcoma and Oropharyngeal Cancer Cells.

Cancer is a significant health problem worldwide; consequently, new therapeutic alternatives are being investigated, including those found in the vegetable kingdom. Eugenol (Eug) has attracted attention for its therapeutic properties, especially in stomatology. The purpose of this study was to investigate the cytotoxicity of Eug, in vitro, on osteosarcoma (SAOS-2) and oropharyngeal squamous cancer (Detroit-562) cells, as well as its potential irritant effect in ovo at the level of the chorioallantoic membrane (CAM). The data obtained following a 72 h Eug treatment highlighted the reduction in cell viability up to 41% in SAOS-2 cells and up to 37% in Detroit-562 cells, respectively. The apoptotic-like effect of Eug was indicated by the changes in cell morphology and nuclear aspect; the increase in caspase-3/7, -8 and -9 activity; the elevated expression of Bax and Bad genes; and the increase in luminescence signal (indicating phosphatidylserine externalization) that preceded the increase in fluorescence signal (indicating the compromise of membrane integrity). Regarding the vascular effects, slight signs of coagulation and vascular lysis were observed, with an irritation score of 1.69 for Eug 1 mM. Based on these results, the efficiency of Eug in cancer treatment is yet to be clarified.

Calcium hypochlorite cytotoxicity mechanism in fibroblasts and effect on osteoblast mineralization.

To determine the cytotoxicity mechanism of 2.5% calcium hypochlorite [Ca(OCl)2 ] in L929 fibroblasts and the effect of this solution on human osteoblast-like cells (Saos-2) mineralization, compared to that of 2.5% sodium hypochlorite (NaOCl). L929 fibroblasts were exposed to Ca(OCl)2 and NaOCl at different dilutions for 10 min. Cell metabolism was assessed by methyl-thiazole-tetrazolium (MTT); lysosome integrity, by neutral red (NR) assay; type of cell death, by flow cytometry (apoptosis/necrosis); cytoskeleton, by actin and α-tubulin fluorescence and cell ultrastructure, by transmission electron microscopy (TEM). The alkaline phosphatase (ALP) activity and mineralized nodule formation were determined in Saos-2 by thymolphthalein release and alizarin red staining (ARS), respectively. The data were analysed by two-way anova and Bonferroni's post-test (α = .05). Ca(OCl)2 promoted higher cell viability and a lower percentage of apoptosis and necrosis than NaOCl (p < .05). Ca(OCl)2 and NaOCl decreased cell metabolism and lysosome integrity, induced the breakdown of microtubules and actin filaments, promoted alterations of rough endoplasmic reticulum and disruption of mitochondrial cristae. Additionally, Ca(OCl)2 did not induce ALP activity and had no effect on mineralized nodules formation. Although Ca(OCl)2 and NaOCl promoted the same cytotoxicity mechanism, Ca(OCl)2 was less cytotoxic than NaOCl. As for ALP activity, no differences were observed between NaOCl and Ca(OCl)2 . The production of mineralized nodules induced by Ca(OCl)2 was lower than those induced by NaOCl, but was not different from those induced by the control group.

Effects of surface micro-deformation on the cellular response to metallic implant materials

In the current study, it is aimed to get a comprehensive understanding of how cellular response to metallic biomaterial surfaces can be controlled via surface parameter specifics, as well as microstructural modifications. For this purpose, a surface micro-deformation procedure was designed where patterns with different parameters, specifically different indent size and repeating frequencies, were created on 316 L stainless steel sample surfaces by using a Vicker's microhardness testing device. The effects of the changes in surface properties following the formation of the different patterns were characterized via scanning electron microscopy (SEM), optical microscopy and profilometer. It was observed that surface roughness significantly increased as a result of the surface micro-deformation process and additionally, dislocation activities of different levels were triggered depending on the specifics of the formed micro-deformation pattern. The effects of the surface micro-deformation process on cellular response were investigated through in vitro experiments where Saos-2 cell line was used. Significant improvements were obtained in terms of cellular viability, proliferation, attachment and cell differentiation behaviors on the samples with surface micro-deformation. Correlating the effects surface parameters such as surface roughness, dislocation density close to the surface and topographical feature specifics on cellular response, it has been observed that by manipulating the metal microstructure and optimizing the surface micro-deformation patterning parameters, cellular response can be significantly enhanced. It was shown that specific surface patterns with smaller indent depth and narrower spacings, as well as optimum dislocation density levels and surface roughness yields superior cellular response. Overall, the obtained information about the specifics of surface features of metallic biomaterials on cellular response can be used for the design of novel implant surface modification methods to improve osseointegration.

Bioactive Glasses Containing Strontium or Magnesium Ions to Enhance the Biological Response in Bone Regeneration.

The non-surgical treatments are being required to reconstruct damaged tissue, prioritizing our body's natural healing process. Thus, the use of bioactive materials such as bioactive glass has been studied to support the repair and restoration of hard and soft tissue. Thus, in this work Bioglass 45S5 was developed, adding 1 and 2%mol of SrO or MgO and the physical and biological properties were evaluated. The addition of MgO and SrO at the studied concentrations promoted the slight increase in non-bridging oxygens number, observed through the temperature shift in phase transitions to lower values compared to Bioglass 45S5. The insertion of the ions also showed a positive effect on Saos-2 cell viability, decreasing the cytotoxic of Bioglass 45S5. Besides the Ca/P ratio on the pellets surface demonstrating no evidence of higher reactivity between Bioglass 45S5 and Bioglass with Sr and Mg, micrographs show that at 24 h the Ca/P rich layer is denser than in Bioglass 45S5 after the contact with simulated body fluid. The samples with Sr and Mg show a higher antibacterial effect compared to Bioglass 45S5. The addition of the studied ions may benefit the biological response of Bioglass 45S5 in dental applications as scaffolds or coatings.

CB65 and novel CB65 liposomal system suppress MG63 and Saos-2 osteosarcoma cell growth in vitro

Curable approaches for primary osteosarcoma are inadequate and urge investigation of novel therapeutic formulations. Cannabinoid ligands exert antiproliferative and apoptotic effect on osteosarcoma cells via cannabinoid 2 (CB2) or transient receptor potential vanilloid type (TRPV1) receptors. In this study, we confirmed CB2 receptor expression in MG63 and Saos-2 osteosarcoma cells by qRT-PCR and flow cytometry (FCM), then reported the reduction effect of synthetic specific CB2 receptor agonist CB65 on the proliferation of osteosarcoma cells by WST-1 (water-soluble tetrazolium-1) and RTCA (real-time impedance-based proliferation). CB65 revealed an IC50 (inhibitory concentration) for MG63 and Saos-2 cells as 1.11 × 10−11 and 4.95 × 10−11 M, respectively. The specific antiproliferative effect of CB65 on osteosarcoma cells was inhibited by CB2 antagonist AM630. CB65 induced late apoptosis of MG63 and Saos-2 cells at 24 and 48 h, respectively by FCM when applied submaximal concentration. A novel CB65 liposomal system was generated by a thin film hydration method with optimal particle size (141.7 ± 0.6 nm), polydispersity index (0.451 ± 0.026), and zeta potential (−10.9 ± 0.3 mV) values. The encapsulation efficiency (EE%) of the CB65-loaded liposomal formulation was 51.12%. The CB65 and CB65-loaded liposomal formulation releasing IC50 of CB65 reduced proliferation by RTCA and invasion by scratch assay and induced late apoptosis of MG63 and Saos-2 cells, by FCM. Our results demonstrate the CB2 receptor-mediated antiproliferative and apoptotic effect of a new liposomal CB65 delivery system on osteosarcoma cells that can be used as a targeted and intelligent tool for bone tumors to ameliorate pediatric bone cancers following in vivo validation.

Improvements in mechanical, corrosion, and biocompatibility properties of Mg–Zr–Sr–Dy alloys via extrusion for biodegradable implant applications

In this study, extrusion was performed on Mg‒Zr‒Sr‒Dy alloys for improving their mechanical, corrosion, and biocompatibility properties. Effects of extrusion and alloying elements on the microstructural characteristics, tensile and compressive strengths, corrosion behavior, and biocompatibility were investigated. The Mg‒Zr‒Sr‒Dy alloys were composed of an α-Mg matrix containing {101¯2} extension twins and secondary phases of intermetallic compounds Mg17Sr2 and Mg2Dy. Evolution of basal and rare earth (RE) textures was observed in the extruded alloys and an increase in Dy content to 2 wt.% resulted in texture randomization and strengthening of the RE component, mainly due to particle-stimulated nucleation and a change from discontinuous dynamic recrystallization to continuous dynamic recrystallization, which also led to an improved tension–compression yield asymmetry of 0.87. Extrusion of the alloys significantly enhanced their tensile and compressive properties due to improved distribution of alloying elements and formation of textures. Corrosion rates tested by hydrogen evolution testing, potentiodynamic polarization, and electrical impedance spectroscopy showed similar trends for each composition, and the lowest corrosion rate of 3.37 mmy−1 was observed for the Mg-1Zr-0.5Sr-1Dy in the potentiodynamic polarization testing. Dy2O3 was observed in the inner layers of the Mg(OH)2 protective films, whose protective efficacy was confirmed by charge-transfer and film resistances. A comparison among the minimum CRs observed in this study and previously studied as-cast Mg‒Zr‒Sr‒Dy and extruded Mg‒Zr‒Sr alloys, demonstrates that both the extrusion process and addition of Dy in Mg‒Zr‒Sr improved the CR. Similarly, extruded Mg–Zr–Sr–Dy alloys showed improved cell viability and adhesion of human osteoblast–like SaOS2 cells due to increased corrosion resistance and enhanced Sr distribution within the Mg matrix.

Mechanical force application and inflammation induce osteoclastogenesis by independent pathways.

To investigate the functional changes of PDL fibroblasts in the presence of mechanical force, inflammation, or a combination of force and inflammation. Inflammatory supernatants were prepared by inoculating human neutrophils with Porphyromonas gingivalis. Primary human PDL fibroblasts (PDLF), gingival fibroblasts (GFs), and osteoblasts (Saos2) were then exposed to the inflammatory supernatants. Orthodontic force on the PDLFs was simulated by centrifugation. Analyses included cell proliferation, cell viability, cell cycle, and collagen expression, as well as osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-Β ligand (RANKL) expression. Mechanical force did not affect PDLF viability, but it increased the metabolic rate compared to resting cells. Force application shifted the PDLF cell cycle to the G0/G1 phase, arresting cell proliferation and leading to elevated collagen production, mild OPG level elevation, and robust RANKL level elevation. Including an inflammatory supernatant in the presence of force did not affect PDLF viability, proliferation, or cytokine expression. By contrast, the inflammatory supernatant increased RANKL expression in GFs, but not in Saos2 cells. Applying mechanical force significantly affects PDLF function. Although inflammation had no effect on PDLF or Saos2 cells, it promoted RANKL expression in GF cells. Within the limitations of the in vitro model, the results suggest that periodontal inflammation and mechanical forces could affect bone catabolism through effects on different cell types, which may culminate in synergistic bone resorption.

Molecular docking, synthesis, anticancer activity, and metabolomics study of boronic acid ester-containing fingolimod derivatives.

In recent years, drugs that contain boronic acid groups, such as ixazomib (Ninlaro™) and bortezomib (Velcade™), have been used in the treatment of bone marrow cancer.The activity of compounds has been found to increase with the addition of boron atoms to the structure. In addition to these compounds, studies have found that fingolimod (FTY720) is more effective against breast cancer than cisplatin. Therefore, in this study, the first examples of boron-containing derivatives of fingolimod were designed and synthesized; in addition, their structures were confirmed by spectroscopic techniques. The synthesized boron-containing drug candidates were found to significantly inhibit cell proliferation and induce apoptosis-mediated cell death in HT-29 (colorectal cells), SaOs-2 (osteosarcoma cells), and U87-MG (glioblastoma cells). Moreover, we revealed that the anticancer effects of boron-containing fingolimod compounds were found to be significantly enhanced over boron-free control groups and, strikingly, over the widely used anticancer drug 5-fluorouracil. The metabolomic analysis confirmed that administration of the boron-containing drug candidates induces significant changes in the metabolite profiles in HT-29, SaOs-2, and U87-MG cells. Altogether, our results showed that boron-containing fingolimod compounds can be further examined to reveal their potential as anticancer drug candidates.

Gossypetin Is a Novel Modulator of Inflammatory Cytokine Production and a Suppressor of Osteosarcoma Cell Growth.

Osteosarcoma (OS) is a common childhood sarcoma, and its treatment is hindered by adverse effects, chemoresistance, and recurrence. Interleukin (IL)-6 production by tumors plays a significant role in inflammation, carcinogenesis, and metastasis. This study aimed to investigate the antiproliferative potential of luteolin derivatives in OS and to evaluate interleukin production. MG-63, Saos-2, HOS, and 143B human OS cell lines were incubated with luteolin and eight derivatives containing hydroxy, chlorine, or alkyl substitutions. The cell viability and growth were evaluated in the presence of these compounds. Apoptosis was also examined through the analysis of the Bax expression and caspase-3 activity. Finally, the gossypetin effects were measured regarding the production of proinflammatory cytokines interleukin (IL)-6, IL-1β, and IL-12p70. Our findings show that gossypetin was the most potent compound, with proliferation-suppressing activities that induced a series of critical events, including the inhibition of the cell viability and growth. Apoptosis was associated with enhanced caspase-3 activity and increased Bax expression, indicating the involvement of the intrinsic pathway of apoptosis. Moreover, pre-/co-treatment with gossypetin significantly reduced the autocrine production of proinflammatory cytokines. Further investigation is required; nevertheless, considering the link between inflammation, carcinogenesis, and metastasis in OS, our findings suggest that gossypetin exhibits anti-proliferative and anti-inflammatory properties that are potentially relevant in the clinical context.

Ph-Responsive Alendronic Acid-Coated Liposomes for Improved Treatment Osteosarcoma

Objective Current research work aimed to develop pH-responsive osteosarcoma-targeted liposomes composed of non-oncology drugs previously identified for repositioning purposes. Material and Methods Using thin film hydration method, the Ketoconazole (KCZ)-, Simvastatin (SVN)-, and Niclosamide (NSD)-loaded non-targeted liposomes (KLs, SLs, and NLs respectively) were developed individually. The Aledronic acid-Choleteryl hemiscuccinate conjugate (AA-CHSC) was synthesized and confirmed using FTIR and 1H-NMR analysis. The AA-CHSC coated liposomes (pH sensitive and targeted liposome: PT-KLs, PT-SLs, and PT-NLs) were developed individually for the treatment of osteosarcoma with improved efficacy and reduced drug’s primary effects. The developed non-targeted and targeted liposomes were characterized for drug contentt,vesicle size, surface morphology using transmission electron microscope (TEM), in vitro pH-sensitive drug release behaviour using dialysis bag technique, and in vitro cytotoxicity characteristics against osteosarcoma cells. Results All non-targeted liposomes showed %drug content and mean vesicle size in the range of 41-75% and 161-182 nm, respectively. The AA-CHSC insertion into the liposomal membrane (targeted liposomes) has substantially improved the drug solubility in the membrane as a result of its amphiphilic nature. Furthermore, the targeted liposomes showed moderately increased mean vesicle size (203-210 nm) validating the surface modification. The TEM image revealed the formation of spherical, nearly spherical, and non-aggregated liposomes. The AA-CHSC insertion also caused liposomes sensitive to tumor pH (5.8); as a result, substantially higher drug release (58-80%) was observed as compared to non-targeted liposomes (34-52%). The cytotoxicity study results revealed substantially higher osteosarcoma cell (Saos-2) growth inhibition characteristics of targeted liposomes. Conclusions In conclusion, the developed targeted liposomes have potential application in the treatment of osteosarcoma. In addition, detailed anticancer activities should be revealed for the combination of targeted liposomes as the combination caused almost similar cytotoxicity as that of individual targeted liposomes.

Differing responses of osteogenic cell lines to β-glycerophosphate

Ascorbic acid (Asc), dexamethasone (Dex) and β-glycerophosphate (β-Gly) are commonly used to promote osteogenic behaviour by osteoblasts in vitro. According to the literature, several osteosarcoma cells lines appear to respond differently to the latter with regards to proliferation kinetics and osteogenic gene transcription. Unsurprisingly, these differences lead to contrasting data between publications that necessitate preliminary studies to confirm the phenotype of the chosen osteosarcoma cell line in the presence of Asc, Dex and β-Gly. The present study exposed Saos-2 cells to different combinations of Asc, Dex and β-Gly for 14 days and compared the response with immortalised human mesenchymal stromal/stem cells (MSCs). Cell numbers, cytotoxicity, mineralised matrix deposition and cell proliferation were analysed to assess osteoblast-like behaviour in the presence of Asc, Dex and β-Gly. Additionally, gene expression of runt-related transcription factor 2 (RUNX2); osteocalcin (OCN); alkaline phosphatase (ALP); phosphate regulating endopeptidase homolog X-linked (PHEX); marker of proliferation MKI67 and proliferating cell nuclear antigen (PCNA) was performed every two days during the 14-day cultures. It was found that proliferation of Saos-2 cells was significantly decreased by the presence of β-Gly which contrasted with hMSCs where no change was observed. Furthermore, unlike hMSCs, Saos-2 cells demonstrated an upregulated expression of late osteoblastic markers, OCN and PHEX that suggested β-Gly could affect later stages of osteogenic differentiation. In summary, it is important to consider that β-Gly significantly affects key cell processes of Saos-2 when using it as an osteoblast-like cell model.

Bio-inspired nanoporous scaffold: electrospun hybrid fibers based on self-assembled block copolymer mineralized with inorganic nanoparticles for bone tissue engineering

Mineralized, bio-inspired nanofibrous scaffolds with controllable architecture and capable of mimicking essential characteristics of bone extracellular matrix at the micro- and nanoscale offer a promising strategy to restore functions or elicit favorable responses for bone tissue regeneration and repair. In this study, a simple approach to fabricate a hybrid scaffold with porous fibers for bone tissue engineering is presented. Non-woven multifunctional nano- and microfibers were fabricated using a block copolymer of poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) (PL-b-CL) as a matrix and hydroxyapatite (HA) as a functional agent, dissolved in a binary solvent mixture. Physicochemical and thermal characterization as well as biocompatibility analyses were carried out using SaOS-2 cells. The results showed fibers with highly porous surfaces whose pore diameters range in the nanometer scale and all scaffolds exhibited hydrophobicity. HA-modified scaffolds significantly improved cell metabolic activity and proliferation as compared to pristine scaffolds. The biodegradable and biocompatible scaffolds proposed in this study carry great potential for various biomedical applications and in the future, it is expected that they can be used for controlled drug delivery by incorporating growth factors, proteins, or drugs to reduce the inflammatory response and/or to promote bone repair.

MiR-4270 acts as a tumor suppressor by directly targeting Bcl-xL in human osteosarcoma cells.

Chondrosarcomas and osteosarcomas are malignant bone tumors with a poor prognosis when unresectable or metastasized. Moreover, radiotherapy and chemotherapy could be ineffective. MiRNAs represent an alternative therapeutic approach. Based on high-throughput functional screening, we identified four miRNAs with a potential antiproliferative effect on SW1353 chondrosarcoma cells. Individual functional validations were then performed in SW1353 cells, as well as in three osteosarcoma cell lines. The antiproliferative and cytotoxic effects of miRNAs were evaluated in comparison with a positive control, miR-342-5p. The cytotoxic effect of four selected miRNAs was not confirmed on SW1353 cells, but we unambiguously revealed that miR-4270 had a potent cytotoxic effect on HOS and MG-63 osteosarcoma cell lines, but not on SaOS-2 cell line. Furthermore, like miR-342-5p, miR-4270 induced apoptosis in these two cell lines. In addition, we provided the first report of Bcl-xL as a direct target of miR-4270. MiR-4270 also decreased the expression of the anti-apoptotic protein Mcl-1, and increased the expression of the pro-apoptotic protein Bak. Our findings demonstrated that miR-4270 has tumor suppressive activity in osteosarcoma cells, particularly through Bcl-xL downregulation.