Multiple Effects of Resveratrol on Osteosarcoma Cell Lines

Three-dimensional (3D) polylactic acid gradient scaffold to study the behavior of osteosarcoma cells under dynamic conditions

This study adopts an in vitro method to recapitulate the behavior of Saos-2 cells, using a system composed of a perfusion bioreactor and poly-L-lactic acid (PLLA) scaffold fabricated using the low-cost thermally-induced phase separation (TIPS) technique. Four distinct scaffold morphologies with different pore sizes were fabricated, characterized by Scanning electron microscopy and micro-CT analysis and tested with osteosarcoma cells under static and dynamic environments to identify the best morphology for cellular growth. In order to accomplish this purpose, cell growth and matrix deposition of the Saos-2 osteosarcoma cell line were assessed using Picogreen and OsteoImage assays. The obtained data allowed us to identify the morphology that better promotes Saos-2 cellular activity in static and dynamic conditions. These findings provided valuable insights into scaffold design and fabrication strategies, emphasizing the importance of the dynamic culture to recreate an appropriate 3D osteosarcoma model. Remarkably, the gradient scaffold exhibits promise for osteosarcoma applications, offering the potential for targeted tissue engineering approaches.

Plant molecules reinforce bone repair: Novel insights into phenol-modified bone tissue engineering scaffolds for the treatment of bone defects

Bone defects have become a major cause of disability and death. To overcome the limitations of natural bone implants, including donor shortages and immune rejection risks, bone tissue engineering (BTE) scaffolds have emerged as a promising therapy for bone defects. Despite possessing good biocompatibility, these metal, ceramic and polymer-based scaffolds are still challenged by the harsh conditions in bone defect sites. ROS accumulation, bacterial infection, excessive inflammation, compromised blood supply deficiency and tumor recurrence negatively impact bone tissue cells (BTCs) and hinder the osteointegration of BTE scaffolds. Phenolic compounds, derived from plants and fruits, have gained growing application in treating inflammatory, infectious and aging-related diseases due to their antioxidant ability conferred by phenolic hydroxyl groups. The prevalent interactions between phenols and functional groups also facilitate their utilization in fabricating scaffolds. Consequently, phenols are increasingly incorporated into BTE scaffolds to boost therapeutic efficacy in bone defect. This review demonstrated the effects of phenols on BTCs and bone defect microenvironment, summarized the intrinsic mechanisms, presented the advances in phenol-modified BTE scaffolds and analyzed their potential risks in practical applications. Overall, phenol-modified BTE scaffolds hold great potential for repairing bone defects, offering novel patterns for BTE scaffold construction and advancing traumatological medicine.

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.

Special Issue "Osteosarcomas: Treatment Strategies"

This Special Issue, titled "Osteosarcomas: Treatment Strategies", aims to overview the recent and future research trends related to the treatment of osteosarcoma [...].

Multi-Anticancer Activities of Phytoestrogens in Human Osteosarcoma

Phytoestrogens are plant-derived bioactive compounds with estrogen-like properties. Their potential health benefits, especially in cancer prevention and treatment, have been a subject of considerable research in the past decade. Phytoestrogens exert their effects, at least in part, through interactions with estrogen receptors (ERs), mimicking or inhibiting the actions of natural estrogens. Recently, there has been growing interest in exploring the impact of phytoestrogens on osteosarcoma (OS), a type of bone malignancy that primarily affects children and young adults and is currently presenting limited treatment options. Considering the critical role of the estrogen/ERs axis in bone development and growth, the modulation of ERs has emerged as a highly promising approach in the treatment of OS. This review provides an extensive overview of current literature on the effects of phytoestrogens on human OS models. It delves into the multiple mechanisms through which these molecules regulate the cell cycle, apoptosis, and key pathways implicated in the growth and progression of OS, including ER signaling. Moreover, potential interactions between phytoestrogens and conventional chemotherapy agents commonly used in OS treatment will be examined. Understanding the impact of these compounds in OS holds great promise for developing novel therapeutic approaches that can augment current OS treatment modalities.

Alternations of NF-κB Signaling by Natural Compounds in Muscle-Derived Cancers

The NF-κB-signaling pathway plays a crucial role in cancer progression, including muscle-derived cancers such as rhabdomyosarcoma or sarcoma. Several natural compounds have been studied for their ability to alter NF-κB signaling in these types of cancers. This review paper summarizes the current knowledge on the effects of natural compounds, including curcumin, resveratrol, quercetin, epigallocatechin-3-gallate, and berberine, on NF-κB signaling in muscle-derived cancers. These compounds have been shown to inhibit NF-κB signaling in rhabdomyosarcoma cells through various mechanisms, such as inhibiting the activation of the IKK complex and the NF-κB transcription factor. These findings suggest that natural compounds could be potential therapeutic agents for muscle-derived cancers. However, further research is needed to fully understand their mechanisms of action and potential clinical applications.

Challenges and opportunities for improving the druggability of natural product: Why need drug delivery system?

Bioactive natural products (BNPs) are the marrow of medicinal plants, which are the secondary metabolites of organisms and have been the most famous drug discovery database. Bioactive natural products are famous for their enormous number and great safety in medical applications. However, BNPs are troubled by their poor druggability compared with synthesis drugs and are challenged as medicine (only a few BNPs are applied in clinical settings). In order to find a reasonable solution to improving the druggability of BNPs, this review summarizes their bioactive nature based on the enormous pharmacological research and tries to explain the reasons for the poor druggability of BNPs. And then focused on the boosting research on BNPs loaded drug delivery systems, this review further concludes the advantages of drug delivery systems on the druggability improvement of BNPs from the perspective of their bioactive nature, discusses why BNPs need drug delivery systems, and predicts the next direction.

Resveratrol Loaded by Folate-Modified Liposomes Inhibits Osteosarcoma Growth and Lung Metastasis via Regulating JAK2/STAT3 Pathway

Background

Osteosarcoma is a malignant bone tumor with a high rate of lung metastasis and mortality. It has been demonstrated that resveratrol can inhibit tumor proliferation and metastasis, but its application is limited due to poor water solubility and low bioavailability. In this study, we proposed to prepare folate-modified liposomes loaded with resveratrol to investigate its anti-osteosarcoma effect in vitro and in vivo.

Methods

We prepared and characterized resveratrol liposomes modified with folate (denoted as, FA-Res/Lps). The effects of FA-Res/Lps on human osteosarcoma cell 143B proliferation, apoptosis, and migration were investigated by MTT, cell cloning, wound-healing assay, transwell, and flow cytometry. A xenograft tumor and lung metastasis model of osteosarcoma was constructed to study the therapeutic effects of FA-Res/Lps on the growth and metastasis of osteosarcoma in vivo.

Results

The FA-Res/Lps were prepared with a particle size of 118.5 ± 0.71 and a small dispersion coefficient of 0.154 ± 0.005. We found that FA-modified liposomes significantly increased resveratrol uptake by osteosarcoma cells 143B in flow cytometric assay, resulting in FA-Res/Lps, which inhibit tumor proliferation, migration and induce apoptosis more effectively than free Res and Res/Lps. The mechanism of action may be associated with the inhibition of JAK2/STAT3 signaling. In vivo imaging demonstrated that FA-modified DiR-modified liposomes significantly increased the distribution of drugs at the tumor site, leading to significant inhibition of osteosarcoma growth and metastasis by FA-Res/Lps. Furthermore, we found that FA-Res/Lps did not cause any adverse effects on mice body weight, liver, or kidney tissues.

Conclusion

Taken together, the anti-osteosarcoma effect of resveratrol is significantly enhanced when it is loaded into FA-modified liposomes. FA-Res/Lps is a promising strategy for the treatment of osteosarcoma.

Timing Expression of miR203a-3p during OA Disease: Preliminary In Vitro Evidence

Osteoarthritis (OA) is a degenerative bone disease that involves the microenvironment and macroenvironment of joints. Progressive joint tissue degradation and loss of extracellular matrix elements, together with different grades of inflammation, are important hallmarks of OA disease. Therefore, the identification of specific biomarkers to distinguish the stages of disease becomes a primary necessity in clinical practice. To this aim, we investigated the role of miR203a-3p in OA progression starting from the evidence obtained by osteoblasts isolated from joint tissues of OA patients classified according to different Kellgren and Lawrence (KL) grading (KL ≤ 3 and KL > 3) and hMSCs treated with IL-1β. Through qRT-PCR analysis, it was found that osteoblasts (OBs) derived from the KL ≤ 3 group expressed high levels of miR203a-3p and low levels of ILs compared with those of OBs derived from the KL > 3 group. The stimulation with IL-1β improved the expression of miR203a-3p and the methylation of the IL-6 promoter gene, favoring an increase in relative protein expression. The gain and loss of function studies showed that the transfection with miR203a-3p inhibitor alone or in co-treatments with IL-1β was able to induce the expression of CX-43 and SP-1 and to modulate the expression of TAZ, in OBs derived from OA patients with KL ≤ 3 compared with KL > 3. These events, confirmed also by qRT-PCR analysis, Western blot, and ELISA assay performed on hMSCs stimulated with IL-1β, supported our hypothesis about the role of miR203a-3p in OA progression. The results suggested that during the early stage, miR203a-3p displayed a protective role reducing the inflammatory effects on CX-43, SP-1, and TAZ. During the OA progression the downregulation of miR203a-3p and consequently the upregulation of CX-43/SP-1 and TAZ expression improved the inflammatory response and the reorganization of the cytoskeleton. This role led to the subsequent stage of the disease, where the aberrant inflammatory and fibrotic responses determined the destruction of the joint.

Bitter taste signaling in cancer

Pharmacoresistance of cancer cells to many drugs used in chemotherapy remains a major challenge for the treatment of cancer. Multidrug resistance transporters, especially ATP-binding cassette (ABC) transporters, are a major cause of cancer drug resistance since they translocate a broad range of drug compounds across the cell membrane, extruding them out of the cells. The regulation of ABC transporters by bitter taste receptors (TAS2Rs), which might be activated by specific bitter tasting compounds, was described in several types of cells/organs, becoming a potential target for cancer therapy. TAS2Rs expression has been reported in many organs and several types of cancer, like breast, ovarian, prostate, and colorectal cancers, where their activation was shown to be involved in various biological actions (cell survival, apoptosis, molecular transport, among others). Moreover, many TAS2Rs' ligands, such as flavonoids and alkaloids, with well-recognized beneficial properties, including several anticancer effects, have been reported as potential adjuvants in cancer therapies. In this review, we discuss the potential therapeutic role of TAS2Rs and bitter tasting compounds in different types of cancer as a possible way to circumvent chemoresistance.

The Involvement of Natural Polyphenols in Molecular Mechanisms Inducing Apoptosis in Tumor Cells: A Promising Adjuvant in Cancer Therapy

Various literature data show how a diet rich in vegetables could reduce the incidence of several cancers due to the contribution of the natural polyphenols contained in them. Polyphenols are attributed multiple pharmacological actions such as anti-inflammatory, anti-oxidant, antibiotic, antiseptic, anti-allergic, cardioprotective and even anti-tumor properties. The multiple mechanisms involved in their anti-tumor action include signaling pathways modulation associated with cell proliferation, differentiation, migration, angiogenesis, metastasis and cell death. Since the dysregulation of death processes is involved in cancer etiopathology, the natural compounds able to kill cancer cells could be used as new anticancer agents. Apoptosis, a programmed form of cell death, is the most potent defense against cancer and the main mechanism used by both chemotherapy agents and polyphenols. The aim of this review is to provide an update of literature data on the apoptotic molecular mechanisms induced by some representative polyphenol family members in cancer cells. This aspect is particularly important because it may be useful in the design of new therapeutic strategies against cancer involving the polyphenols as adjuvants.

Improving Osteosarcoma Treatment: Comparative Oncology in Action

Osteosarcoma (OSA) is the most common pediatric malignant bone tumor. Although surgery together with neoadjuvant/adjuvant chemotherapy has improved survival for localized OSA, most patients develop recurrent/metastatic disease with a dismally poor outcome. Therapeutic options have not improved for these OSA patients in recent decades. As OSA is a rare and "orphan" tumor, with no distinct targetable driver antigens, the development of new efficient therapies is still an unmet and challenging clinical need. Appropriate animal models are therefore critical for advancement in the field. Despite the undoubted relevance of pre-clinical mouse models in cancer research, they present some intrinsic limitations that may be responsible for the low translational success of novel therapies from the pre-clinical setting to the clinic. From this context emerges the concept of comparative oncology, which has spurred the study of pet dogs as a uniquely valuable model of spontaneous OSA that develops in an immune-competent system with high biological and clinical similarities to corresponding human tumors, including in its metastatic behavior and resistance to conventional therapies. For these reasons, the translational power of studies conducted on OSA-bearing dogs has seen increasing recognition. The most recent and relevant veterinary investigations of novel combinatorial approaches, with a focus on immune-based strategies, that can most likely benefit both canine and human OSA patients have been summarized in this commentary.

The Binomial "Inflammation-Epigenetics" in Breast Cancer Progression and Bone Metastasis: IL-1β Actions Are Influenced by TET Inhibitor in MCF-7 Cell Line

The existence of a tight relationship between inflammation and epigenetics that in primary breast tumor cells can lead to tumor progression and the formation of bone metastases was investigated. It was highlighted how the induction of tumor progression and bone metastasis by Interleukin-1 beta, in a non-metastatic breast cancer cell line, MCF-7, was dependent on the de-methylating actions of ten-eleven translocation proteins (TETs). In fact, the inhibition of their activity by the Bobcat339 molecule, an inhibitor of TET enzymes, determined on the one hand, the modulation of the epithelial-mesenchymal transition process, and on the other hand, the reduction in the expression of markers of bone metastasis, indicating that the epigenetic action of TETs is a prerequisite for IL-1β-dependent tumor progression and bone metastasis formation.

A mechanistic review of chinese medicine polyphenols on bone formation and resorption

Bone reconstruction includes a steady state system of bone formation and bone absorption. This tight coupling requires subtle coordination between osteoblasts and osteoclasts. If this balance is broken, it will lead to bone mass loss, bone density reduction, and bone metabolic diseases, such as osteoporosis. Polyphenols in Chinese herbal medicines are active ingredients in plant extracts with high safety and few side effects, and they can play a role in affecting bone formation and bone resorption. Some of these have estrogen-like effects and can better target bone health in postmenopausal women. The purpose of this review is to provide comprehensive information on the mechanisms underlying the relationship between traditional Chinese medicine polyphenols and bone formation or bone resorption.

Effects of Resveratrol, Curcumin and Quercetin Supplementation on Bone Metabolism—A Systematic Review

Phenolic compounds are natural phytochemicals that have recently reported numerous health benefits. Resveratrol, curcumin, and quercetin have recently received the most attention among these molecules due to their documented antioxidant effects. The review aims to investigate the effects of these molecules on bone metabolism and their role in several diseases such as osteopenia and osteoporosis, bone tumours, and periodontitis. The PubMed/Medline, Web of Science, Google Scholar, Scopus, Cochrane Library, and Embase electronic databases were searched for papers in line with the study topic. According to an English language restriction, the screening period was from January 2012 to 3 July 2022, with the following Boolean keywords: (“resveratrol” AND “bone”); (“curcumin” AND “bone”); (“quercetin” AND “bone”). A total of 36 papers were identified as relevant to the purpose of our investigation. The studies reported the positive effects of the investigated phenolic compounds on bone metabolism and their potential application as adjuvant treatments for osteoporosis, bone tumours, and periodontitis. Furthermore, their use on the titanium surfaces of orthopaedic prostheses could represent a possible application to improve the osteogenic processes and osseointegration. According to the study findings, resveratrol, curcumin, and quercetin are reported to have a wide variety of beneficial effects as supplement therapies. The investigated phenolic compounds seem to positively mediate bone metabolism and osteoclast-related pathologies.