Curcumin inhibits the proliferation and invasion of MG-63 cells through inactivation of the p-JAK2/p-STAT3 pathway

Modulating the JAK/STAT pathway with natural products: potential and challenges in cancer therapy

The Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathway is a critical signaling network governing cellular functions such as immune responses, proliferation, and apoptosis. Dysregulation of this pathway is strongly implicated in cancer progression. This review explores the therapeutic potential of natural products, including Curcumin, Resveratrol, Apigenin, and Epigallocatechin Gallate (EGCG), as modulators of the JAK/STAT pathway. These phytochemicals exhibit anticancer activity by inhibiting JAK/STAT phosphorylation, blocking STAT dimerization, and interfering with STAT-DNA binding. A systematic evaluation of included peer-reviewed studies highlights their promise as complementary agents to conventional cancer therapies. However, challenges such as poor bioavailability and the need for robust clinical validation remain significant hurdles. Addressing these limitations through advanced drug delivery systems and rigorous trials could unlock their full potential in cancer treatment.

Cancer chemoprevention: signaling pathways and strategic approaches

Although cancer chemopreventive agents have been confirmed to effectively protect high-risk populations from cancer invasion or recurrence, only over ten drugs have been approved by the U.S. Food and Drug Administration. Therefore, screening potent cancer chemopreventive agents is crucial to reduce the constantly increasing incidence and mortality rate of cancer. Considering the lengthy prevention process, an ideal chemopreventive agent should be nontoxic, inexpensive, and oral. Natural compounds have become a natural treasure reservoir for cancer chemoprevention because of their superior ease of availability, cost-effectiveness, and safety. The benefits of natural compounds as chemopreventive agents in cancer prevention have been confirmed in various studies. In light of this, the present review is intended to fully delineate the entire scope of cancer chemoprevention, and primarily focuses on various aspects of cancer chemoprevention based on natural compounds, specifically focusing on the mechanism of action of natural compounds in cancer prevention, and discussing in detail how they exert cancer prevention effects by affecting classical signaling pathways, immune checkpoints, and gut microbiome. We also introduce novel cancer chemoprevention strategies and summarize the role of natural compounds in improving chemotherapy regimens. Furthermore, we describe strategies for discovering anticancer compounds with low abundance and high activity, revealing the broad prospects of natural compounds in drug discovery for cancer chemoprevention. Moreover, we associate cancer chemoprevention with precision medicine, and discuss the challenges encountered in cancer chemoprevention. Finally, we emphasize the transformative potential of natural compounds in advancing the field of cancer chemoprevention and their ability to introduce more effective and less toxic preventive options for oncology.

Human and canine osteosarcoma cell lines: How do they react upon incubation with calcium phosphate-coated lipid nanoparticles carrying doxorubicin and curcumin?

Osteosarcoma (OSA) is a bone cancer that affects both humans and animals, with dogs being particularly vulnerable. Standard therapy is often limited by multidrug resistance (MDR), primarily due to the overexpression of P-glycoprotein (P-gp), which expels drugs from the cells, reducing their efficacy. To overcome this challenge, drug delivery systems (DDS) and P-gp modulators have been explored. However, developing DDS that selectively target cancer cells remains difficult, with many current options lacking efficiency. Our research group has recently developed an innovative type of nanoparticle with a lipid core and a calcium phosphate shell (CaP-NPs), which enhances the uptake of doxorubicin (DOXO) in OSA cells. In this study, we loaded a lipophilic ester of doxorubicin (C12DOXO) and curcumin (CURC), a natural P-gp modulator, into CaP-NPs and co-incubated them into human and canine OSA cell lines, including DOXO-resistant cells. The results demonstrated a significant reduction in viability in human OSA cells. Additionally, the combination treatment led to a further increase in C12DOXO retention when cells were also treated with the P-gp inhibitor verapamil, indicating enhanced efficacy against MDR mechanisms. Notably, canine OSA cells exhibited a distinct response pattern, suggesting the presence of species-specific differences that warrant further investigation.

Curcumin Inhibits the Growth of Hepatocellular Carcinoma via the MARCH1-mediated Modulation of JAK2/STAT3 Signaling

BACKGROUND

Curcumin has been reported to have anti-hepatocellular carcinoma (HCC) effects, but the underlying mechanism is not well known.

OBJECTIVES

To investigate whether membrane-associated RING-CH 1 (MARCH1) is involved in the curcumin-induced growth suppression in HCC and its underlying molecular mechanism. A few recent patents for curcumin for cancer are also reviewed in this article.

METHODS

The effect of curcumin on growth inhibition of HCC cells was analyzed through in vitro and in vivo experiments, and the expression levels of MARCH1, Bcl-2, VEGF, cyclin B1, cyclin D1, and JAK2/STAT3 signaling molecules were measured in HCC cells and the xenograft tumors in nude mice. Cell transfection with MARCH1 siRNAs or expression plasmid was used to explore the role of MARCH1 in the curcumin-induced growth inhibition of HCC cells.

RESULTS

Curcumin inhibited cell proliferation, promoted apoptosis, and arrested the cell cycle at the G2/M phase in HCC cells with the decrease of Bcl-2, VEGF, cyclin B1, and cyclin D1 expression as well as JAK2 and STAT3 phosphorylation, resulting in the growth suppression of HCC cells. MARCH1 is highly expressed in HCC cells, and its expression was downregulated after curcumin treatment in a dose-dependent manner. The knockdown of MARCH1 by siRNA decreased the phosphorylation levels of JAK2 and STAT3 and inhibited the growth of HCC cells. In contrast, opposite results were observed when HCC cells overexpressed MARCH1. A xenograft tumor model in nude mice also showed that curcumin downregulated MARCH1 expression and decelerated the growth of transplanted HCC with the downregulation of JAK2/STAT3 signaling and functional molecules. The ADC value of MRI analysis showed that curcumin slowed down the progression of HCC.

CONCLUSION

Our results demonstrated that curcumin may inhibit the activation of JAK2/STAT3 signaling pathway by downregulating MARCH1 expression, resulting in the growth suppression of HCC. MARCH1 may be a novel target of curcumin in HCC treatment.

New insights into the role of the CHI3L2 protein in invasive ductal breast carcinoma

Chitinase-like proteins have multiple biological functions that promote tumor growth, angiogenesis and metastasis. Expression of CHI3L2, which is similar in structure to CHI3L1, is detected in glioma cells and tumor-associated macrophages (TAMs) in glioma and breast cancer. However, its exact role remains unclear. We analyzed the expression of CHI3L2 in 74 invasive ductal breast carcinoma (IDC) tumors, breast cancer and macrophages cell cultures using immunohistochemistry, immunofluorescence, Western blot and PCR methods. Clinicopathologic data were included in the analysis. The results obtained show that CHI3L2 expression decreases with increasing degree of tumor grade and negative status of estrogen (ER) and progesterone receptors (PR). Furthermore, CHI3L2 is significantly and positively correlated with phosphorylation of STAT-3 and ERK1/2 signaling pathways, but negatively correlated with macrophage infiltration. CHI3L2 is expressed both in the cytoplasm of cancer cells and in macrophages and may regulate STAT-3 and ERK1/2 phosphorylation in breast cancer cell lines. Analysis of the clinicopathologic data revealed that CHI3L2 levels had no effect on patient survival. CHI3L2 expression may be specific for cancer cells in IDC and involved in cross-talk with the tumor microenvironment. Our study has shown that IDC cancer cells express the CHI3L2 protein, possibly indicating a novel function of this protein.

Treatment with autophagic inhibitors enhances oligonol‑induced apoptotic effects in nasopharyngeal carcinoma cells

Although the combination of chemotherapy and radiotherapy has increased the survival rate of patients with nasopharyngeal carcinoma (NPC), certain patients do not respond well to the treatment and have a poor prognosis. Therefore, novel therapeutic drugs and strategies to improve prognosis of patients with NPC are required. As certain plant extracts can suppress the viability of cancer cells, the present study investigated whether oligonol, a polyphenolic compound primarily found in lychee fruit, exerts anticancer activities in NPC cells. MTT, ELISA and immunoblotting were performed to investigate cell survival, cytokeratin-18 fragment release, and the expression of apoptosis and autophagy markers, respectively. Oligonol decreased the viability of NPC-TW01 and NPC/HK1NPC cell lines. Oligonol increased the protein expression of several apoptosis markers, including cleaved caspase-8 and -3, cleaved PARP and cytokeratin 18 fragment. Moreover, it also increased expression of autophagy markers Beclin 1 and LC3-II, as well as LC3-II/LC3-I ratio in both NPC cell lines. Furthermore, treatment with autophagy inhibitors 3-methyladenine or LY294002 significantly increased oligonol-induced viability inhibition in NPC-TW01 cells. Combined treatment of oligonol + LY294002 reduced LC3-II expression and the LC3II/LC3I ratio while increasing cleaved caspase-8 and -3, cleaved PARP and cytokeratin 18 fragment expression in NPC-TW01 cells. These findings indicated autophagy inhibitors could enhance viability inhibition and apoptotic effects induced by oligonol in NPC cells.

The nuclear export protein exportin-1 in solid malignant tumours: From biology to clinical trials

BACKGROUND

Exportin-1 (XPO1), a crucial protein regulating nuclear-cytoplasmic transport, is frequently overexpressed in various cancers, driving tumor progression and drug resistance. This makes XPO1 an attractive therapeutic target. Over the past few decades, the number of available nuclear export-selective inhibitors has been increasing. Only KPT-330 (selinexor) has been successfully used for treating haematological malignancies, and KPT-8602 (eltanexor) has been used for treating haematologic tumours in clinical trials. However, the use of nuclear export-selective inhibitors for the inhibition of XPO1 expression has yet to be thoroughly investigated in clinical studies and therapeutic outcomes for solid tumours.

METHODS

We collected numerous literatures to explain the efficacy of XPO1 Inhibitors in preclinical and clinical studies of a wide range of solid tumours.

RESULTS

In this review, we focus on the nuclear export function of XPO1 and results from clinical trials of its inhibitors in solid malignant tumours. We summarized the mechanism of action and therapeutic potential of XPO1 inhibitors, as well as adverse effects and response biomarkers.

CONCLUSION

XPO1 inhibition has emerged as a promising therapeutic strategy in the fight against cancer, offering a novel approach to targeting tumorigenic processes and overcoming drug resistance. SINE compounds have demonstrated efficacy in a wide range of solid tumours, and ongoing research is focused on optimizing their use, identifying response biomarkers, and developing effective combination therapies.

KEY POINTS

Exportin-1 (XPO1) plays a critical role in mediating nucleocytoplasmic transport and cell cycle. XPO1 dysfunction promotes tumourigenesis and drug resistance within solid tumours. The therapeutic potential and ongoing researches on XPO1 inhibitors in the treatment of solid tumours. Additional researches are essential to address safety concerns and identify biomarkers for predicting patient response to XPO1 inhibitors.

Advancements in Photothermal Therapy Using Near-Infrared Light for Bone Tumors

Bone tumors, particularly osteosarcoma, are prevalent among children and adolescents. This ailment has emerged as the second most frequent cause of cancer-related mortality in adolescents. Conventional treatment methods comprise extensive surgical resection, radiotherapy, and chemotherapy. Consequently, the management of bone tumors and bone regeneration poses significant clinical challenges. Photothermal tumor therapy has attracted considerable attention owing to its minimal invasiveness and high selectivity. However, key challenges have limited its widespread clinical use. Enhancing the tumor specificity of photosensitizers through targeting or localized activation holds potential for better outcomes with fewer adverse effects. Combinations with chemotherapies or immunotherapies also present avenues for improvement. In this review, we provide an overview of the most recent strategies aimed at overcoming the limitations of photothermal therapy (PTT), along with current research directions in the context of bone tumors, including (1) target strategies, (2) photothermal therapy combined with multiple therapies (immunotherapies, chemotherapies, and chemodynamic therapies, magnetic, and photodynamic therapies), and (3) bifunctional scaffolds for photothermal therapy and bone regeneration. We delve into the pros and cons of these combination methods and explore current research focal points. Lastly, we address the challenges and prospects of photothermal combination therapy.

Curcumin suppresses metastasis, invasion, and proliferation in osteosarcoma cells by regulating the EGFR/Src signaling axis

We explored the biological mechanisms by which curcumin (Cur) confronts osteosarcoma (OS) tumorigenesis and potential drug gene targets based on network pharmacology and in vitro cell experiments. Cur has been recognized for its significant role in combating various types of tumors. However, the intrinsic molecular mechanisms through which it affects OS remain uncharted. In this study, we performed network pharmacology methods including protein-protein interaction (PPI) and core target screening, Functional Enrichment Analysis and Network Construction, Molecular Docking, which obtained the potential target of Cur. Meanwhile, cell experiments (wound healing assay, Transwell assay, Western blots, immunofluorescence, et al.) in vitro were performed to verify the targets, and reveal the biological mechanisms. A total of 18 hub genes were identified through our network pharmacological analysis. In vitro studies show that Cur inhibits the proliferation, migration, invasion capabilities of MG63 and U2OS cells. Western blot reveals a down-regulation of p-PI3K, PI3K, p-Akt, Akt, EGFR, Src, p-Src (Tyr416) and STAT3 expression when treated with Cur. Additionally, Cur upregulated epithelial proteins (E-cadherin and Occludin) while decreasing the expression of the mesenchymal protein (N-cadherin). In addition, Cur treatment decreases the EGFR/Src signaling pathway in the presence of active Src overexpression. Cur inhibits the proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) by down-regulating EGFR/Src signaling axis, also resulting in coordinated weakening of its downstream regulatory genes, including Akt, STAT3, Bcl2, ERK1/2, among others signal axis (PI3K/Akt signaling pathway).

Tumor microenvironment phenotypes and prognostic evaluation tools for osteosarcoma characterized by different prognostic outcomes and immunotherapy responses

BACKGROUND

The physiological and immunological characteristics of the tumor microenvironment (TME) have a profound impact on the effectiveness of immunotherapy. The present study aimed to define the TME subtype of osteosarcoma according to the signatures representing the global TME of the tumor, as well as create a new prognostic assessment tool to monitor the prognosis, TME activity and immunotherapy response of patients with osteosarcoma.

METHODS

The enrichment scores of 29 functional gene expression signatures in osteosarcoma samples were calculated by single sample gene set enrichment analysis (ssGSEA). TME classification of osteosarcoma was performed and a prognostic assessment tool was created based on 29 ssGSEA scores to comprehensively correlate them with TME components, immunotherapy efficacy and prognosis of osteosarcoma.

RESULTS

Three TME subtypes were generated that differed in survival, TME activity and immunotherapeutic response. Four differentially expressed genes between TME subtypes were involved in the development of prognostic assessment tools. The established prognosis assessment tool had strong performance in both training and verification cohorts, could be effectively applied to the survival prediction of samples of different ages, genders and transfer states, and could well distinguish the TME status of different samples.

CONCLUSIONS

The present study describes three different TME phenotypes in osteosarcoma, provides a risk stratification tool for osteosarcoma prognosis and TME status assessment, and provides additional information for clinical decision-making of immunotherapy.

Co-delivery of curcumin and si-STAT3 with a bioinspired tumor homing for polydopamine nanoparticles for synergistic osteosarcoma therapy

Purpose

Owing to the complexity of cancer, a synergistic combination of chemotherapy and gene therapy can be a promising therapeutic strategy. This study aimed to use stem cell membrane (SCM)-camouflaged polydopamine nanoparticles for simultaneous delivery of curcumin (CUR) and siRNA-targeting STAT3 (CPDA/siSTAT3@SCM NPs) for osteosarcoma (OS).

Methods

Transmission electron microscopy, UV–Vis absorbance spectra, zeta potential, cell co-localization, and Coomassie bright blue staining were used to characterize CPDA/siSTAT3@SCM NPs constructed by the self-assembly method. Drug release, cellular uptake, cell proliferation, apoptosis, wound healing, and transwell assays were evaluated in vitro. The expression levels of epithelial–mesenchymal transition (EMT)- and apoptosis-related proteins were measured by western blotting. Furthermore, the biodistribution, antitumor efficacy, and biosafety of CPDA/siSTAT3@SCM NPs in an MG63 xenograft mouse model were evaluated.

Results

CPDA/siSTAT3@SCM NPs were successfully synthesized to deliver CUR and siRNA simultaneously, and they showed osteosarcoma-targeting ability. Furthermore, it showed high cellular uptake and excellent synergistic antitumor effects in vitro. CPDA/siSTAT3@SCM NPs suppressed OS cell proliferation, migration, invasion, and EMT progression, and promoted the apoptotic process. In tumor-bearing mice, the treatment with CPDA/siSTAT3@SCM NPs showed an excellent antitumor effect with no side effects in major organs.

Conclusion

This study revealed that CPDA/siSTAT3@SCM NPs can target drug delivery by biomimetic multifunctional nanoparticles to treat OS through chemo-gene combined therapy.

Pterostilbene-Isothiocyanate Inhibits Proliferation of Human MG-63 Osteosarcoma Cells via Abrogating β-Catenin/TCF-4 Interaction-A Mechanistic Insight

Osteosarcoma, a highly metastasizing bone neoplasm, is a leading cause of death and disability in children and adolescents worldwide. Osteosarcoma is only suboptimally responsive to surgery and radio- and chemotherapy, that too with adverse side effects. Hence, there is a necessary need for safer alternative therapeutic approaches. This study evaluated the anticancer effects of the semi-synthetic compound, pterostilbene-isothiocyanate (PTER-ITC), on human osteosarcoma MG-63 cells through cytotoxicity, wound-healing, and transwell-migration assays. Results showed that PTER-ITC specifically inhibited the survival, proliferation, and migration of osteosarcoma cells. PTER-ITC induced apoptosis in MG-63 cells by disrupting mitochondrial membrane potential, as evident from the outcomes of different cytological staining. The antimetastatic potential of PTER-ITC was evaluated through immunostaining, RT-qPCR, and immunoblotting. In silico (molecular docking and dynamic simulation) and, subsequently, biochemical [co-immunoprecipitation (Co-IP) and luciferase reporter] assays deciphered the underlying mode-of-action of this compound. PTER-ITC increased E-cadherin and reduced N-cadherin levels, thereby facilitating the reversal of epithelial-mesenchymal transition (EMT). It also modulated the expressions of proliferative cell nuclear antigen (PCNA), caspase-3, poly [ADP-ribose] polymerase (PARP-1) and matrix metalloproteinase-2/9 (MMPs-2/9) at transcriptional and translational levels. PTER-ITC interfered with the β-catenin/transcription factor-4 (TCF-4) interaction in silico by occupying the β-catenin binding site on TCF-4, confirmed by their reduced physical interactions (Co-IP assay). This inhibited transcriptional activation of TCF-4 by β-catenin (as shown by luciferase reporter assay). In conclusion, PTER-ITC exhibited potent anticancer effects in vitro against human osteosarcoma cells by abrogating the β-catenin/TCF-4 interaction. Altogether, this study suggests that PTER-ITC may be regarded as a new approach for osteosarcoma treatment.

Solamargine induces apoptosis of human renal carcinoma cells via downregulating phosphorylated STAT3 expression

Solamargine (SM), an active compound derived from Solanum nigrum, triggers apoptosis and inhibits the metastatic and oxidative activities of various types of tumor cells. However, the effect of SM on human renal carcinoma cells remains unknown. In the present study, the molecular mechanisms underlying the antitumor effects of SM on ACHN and 786-O cells were elucidated. Specifically, MTT and colony formation assays were conducted to evaluate the impact of SM treatment on the proliferation of ACHN and 786-O cells, and flow cytometry was conducted to determine the influence of SM on the apoptosis rates of these cells. In addition, the expression of target proteins was determined by western blotting. The results revealed that SM not only inhibited cell viability but also promoted the apoptosis of ACHN and 786-O cells in a time- and dose-dependent manner. Moreover, treatment of ACHN and 786-O cells with SM significantly enhanced the caspase-3, caspase-8 and caspase-9 activities. Furthermore, SM downregulated the expression of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) and Bcl-2 but increased the expression of cleaved caspase-3, -8, -9 and Bax. BAY2353, a p-STAT3 inhibitor, inhibited the viability of ACHN and 786-O cells, increased the expression of cleaved caspase-9 and Bax and decreased the expression of p-STAT3 and Bcl-2. Further experiments demonstrated that SM inhibited tumor growth in xenograft nude mice without causing specific toxicity to the major organs. Collectively, these findings indicated that SM not only inhibited the viability but also promoted the apoptosis of ACHN and 786-O cells, through a mechanism involving downregulation of p-STAT3 expression.

Targeting signaling pathways in osteosarcoma: Mechanisms and clinical studies

Osteosarcoma (OS) is a highly prevalent bone malignancy among adolescents, accounting for 40% of all primary malignant bone tumors. Neoadjuvant chemotherapy combined with limb-preserving surgery has effectively reduced patient disability and mortality, but pulmonary metastases and OS cells' resistance to chemotherapeutic agents are pressing challenges in the clinical management of OS. There has been an urgent need to identify new biomarkers for OS to develop specific targeted therapies. Recently, the continued advancements in genomic analysis have contributed to the identification of clinically significant molecular biomarkers for diagnosing OS, acting as therapeutic targets, and predicting prognosis. Additionally, the contemporary molecular classifications have revealed that the signaling pathways, including Wnt/β-catenin, PI3K/AKT/mTOR, JAK/STAT3, Hippo, Notch, PD-1/PD-L1, MAPK, and NF-κB, have an integral role in OS onset, progression, metastasis, and treatment response. These molecular classifications and biological markers have created new avenues for more accurate OS diagnosis and relevant treatment. We herein present a review of the recent findings for the modulatory role of signaling pathways as possible biological markers and treatment targets for OS. This review also discusses current OS therapeutic approaches, including signaling pathway-based therapies developed over the past decade. Additionally, the review covers the signaling targets involved in the curative effects of traditional Chinese medicines in the context of expression regulation of relevant genes and proteins through the signaling pathways to inhibit OS cell growth. These findings are expected to provide directions for integrating genomic, molecular, and clinical profiles to enhance OS diagnosis and treatment.

Deciphering the Signaling Mechanisms of Osteosarcoma Tumorigenesis

Osteosarcoma (OS) is the predominant primary bone tumor in the pediatric and adolescent populations. It has high metastatic potential, with the lungs being the most common site of metastasis. In contrast to many other sarcomas, OS lacks conserved translocations or genetic mutations; instead, it has heterogeneous abnormalities, including somatic DNA copy number alteration, ploidy, chromosomal amplification, and chromosomal loss and gain. Unfortunately, clinical outcomes have not significantly improved in over 30 years. Currently, no effective molecularly targeted therapies are available for this disease. Several genomic studies showed inactivation in the tumor suppressor genes, including p53, RB, and ATRX, and hyperactivation of the tumor promoter genes, including MYC and MDM2, in OS. Alterations in the major signaling pathways, including the PI3K/AKT/mTOR, JAK/STAT, Wnt/β-catenin, NOTCH, Hedgehog/Gli, TGF-β, RTKs, RANK/RANKL, and NF-κB signaling pathways, have been identified in OS development and metastasis. Although OS treatment is currently based on surgical excision and systematic multiagent therapies, several potential targeted therapies are in development. This review focuses on the major signaling pathways of OS, and we propose a biological rationale to consider novel and targeted therapies in the future.

Combination Curcuma longa and Phyllanthus niruri Extract Potentiate Antiproliferative in Triple Negative Breast Cancer MDAMB-231 Cells

BACKGROUND

Triple negative breast cancer cells (TNBC) are a small part of cancer-inducing cells in breast cancer, which are characterized by high metastatic and self-renewal. Self-renewal has the ability to renew itself and loses control of proliferation. Curcuma longa extract (CL) and Phyllanthus niruri extract (PN) known to have anti-proliferative effects on cancer cells. However, the effects of combination CL and PN on TNBC proliferation still unclear.

AIMS

This study aimed to evaluate the antiproliferative effects of the combination CL and PN on TNBC MDAMB-231 and attempted to elucidate the underlying molecular mechanisms.

SUBJECTS AND METHODS

The dried rhizomes of Curcuma longa and the herbs of Phyllanthus niruri were macerated with ethanol for 72 h.The antiproliferative and synergistic effects of combination CL and PN were investigated using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. Combination index values were calculated using CompuSyn (ComboSyn, Inc, Paramus, NJ). The cell cycle and apoptosis assay were determined by propidium iodide (PI) and PI-AnnexinV assay under flow cytometer, respectively. The intracellular ROS levels were evaluated using 2',7'-Dichlorodihydrofluorescein diacetate (DCFDA) assay. The mRNA expressions of proliferation-related genes in the cells were determined using bioinformatic assay.

RESULTS

The CL and PN single treatment caused a potent and dose-dependent decrease in the percentage of viable cells with IC50 value of 13 μg/mL and 45 μg/mL for 24 h, respectively. The combination index values of the different combinations ranged from 0.08 - 0.90, indicating slightly strong to very strong synergistic effects. The combination of CL and PN also remarkably induced the S- and G2/M-phases cell cycle arrest that leading to apoptosis induction. Furthermore, the combination of CL and PN treatment induced the intracellular reactive oxygen species (ROS) levels. Mechanistically, the AKT1, EP300, STAT3 and EGFR signaling as potential targets of combination CL and PN in antiproliferation and antimetastatic of TNBC.

CONCLUSIONS

The combination of CL and PN exerted promising antiproliferative effects in TNBC. Therefore, CL and PN may be considered a potential source for the development of potent anticancer drugs for breast cancer treatment.

Identification of HER2 inhibitors from curcumin derivatives using combination of in silico screening and molecular dynamics simulation

Breast cancer remains a major world health challenge in women. Some Breast cancers are human epidermal growth factor receptor 2 (HER2) positive. Since this protein promotes the growth of cancer cells, it remains a therapeutic target for novel drugs. This study uses in silico model to predict HER2 inhibitors from curcumin derivatives via QSAR, e-pharmacophore, ADMET as well as structure-based virtual screening using Schrodinger suite. The molecular dynamics simulation of lead compounds, reference ligand and co-crystalized ligand was performed using GROMACS. At the end, eight active curcumin derivatives were predicted as inhibitors of HER2 with high binding affinity and better interaction compared with the reference drug (Neratinib) but lower binding affinity compared with the co-crystalized ligand (TAK-285). After prediction of the bioactivity of the molecules using AutoQSAR, the hit compounds showed appreciable inhibitory pIC50 compared with the reference and co-crystalized ligands against HER2. The pharmacokinetics profile predicted the eight hit compounds as drug-like and drug candidates. The MD simulation predicted the stability of the two top-scored compounds (10763284 and 78321412) in complex with HER2 for the final 80 ns of the trajectory period after initial equilibration with higher H-bond interactions in the protein-reference drug complex compared to the hit compounds-HER2 complexes. This study revealed that curcumin derivatives especially (1E,6E)-1,8-bis(4-hydroxy-3-methoxyphenyl)octa-1,6-diene-3,5-dione and (1E,6E)-4-ethyl-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione were identified to demonstrate inhibitory activity against HER2 which is comparable to neratinib. Conclusively, the lead compounds require further in vitro and in vivo experimental validation for the discovery of new HER2 antagonists for breast cancer management.Communicated by Ramaswamy H. Sarma.

Curcumin in human osteosarcoma: From analogs to carriers

Osteosarcoma (osteogenic sarcoma), the most prevalent primary malignant bone tumor in adolescents, confers low survival rates in patients with metastatic disease. Dietary curcumin has a number of anticancer properties but has poor bioavailability. To improve the clinical applications of curcumin, several potential curcumin analogs and nanobased curcumin delivery systems have been developed. In this critical review, we address the biological and pharmacological characteristics of curcumin and its analogs, with an emphasis on strategies to improve the bioactivity and bioavailability of curcumin analogs that may increase their application in the treatment of potent human metastatic osteosarcoma. We highlight promising current multifunctional nanoformulations and three-dimensional printed scaffold systems utilized for the targeting and delivery of curcumin in human osteosarcoma cells. Our purpose is to drive further research on curcumin analogs and carriers to improve their bioavailability and anti-osteosarcoma bioactivity.

Curcumin and its Analogs and Carriers: Potential Therapeutic Strategies for Human Osteosarcoma

Curcumin is a natural polyphenol phytochemical derived from turmeric with antioxidant, anti-inflammatory, and anticancer properties but is concerned about poor solubility in water, absorption, and metabolic stability. Potent metastatic osteosarcoma is the most common primary bone cancer in children, adolescents, and young adults. It is responsible for low survival rates because of its high rate of metastasis to the lungs. To improve poor bioavailability, numerous curcumin analogs were developed to possess anticancer characteristics through a variety of biological pathways involved in cytotoxicity, proliferation, autophagy, sensitizing chemotherapy, and metastases. This review provides an overview of their various pharmacological functions, molecular mechanisms, and therapeutic potential as a remedy for human osteosarcoma. To enhance therapeutic efficacy, several liposomal nanoparticles, nanocarriers, multifunctional micelles, and three-dimensional printed scaffolds have also been developed for the controlled delivery of curcumin targeting human osteosarcoma cells. Consequently, curcumin and several potential analogs and delivery formulations are optimistic candidates to improve the currently available strategy for human osteosarcoma. However, further insight into the mechanism of action of promising curcumin analogs and the development of carriers in clinical trials of osteosarcoma needs to be investigated to improve their overall potency and clinical utility, in particular the anti-metastatic effect.

Cordycepin Induces Apoptosis through JNK-Mediated Caspase Activation in Human OEC-M1 Oral Cancer Cells

Cordycepin, a bioactive compound extracted from Cordyceps sinensis, can induce apoptosis in human OEC-M1 oral cancer cells. However, the exact mechanism is still unclear. The present study aimed to investigate the underlying mechanism of cordycepin-induced apoptosis in OEC-M1 cells. Following treatment with cordycepin, apoptosis was examined and quantified using a DNA laddering assay and a cytokeratin 18 fragment enzyme-linked immunosorbent assay, respectively. Expressions of mitogen-activated protein kinases (MAPKs) and apoptosis-related proteins were detected by the western blot analysis. Our results show that a pan-caspase inhibitor, Z-VAD-FMK, could significantly inhibit cordycepin-induced apoptosis in OEC-M1 cells. In addition, treatment with cordycepin not only activated caspase-8, caspase-9, and caspase-3 but also induced Bid and poly ADP-ribose polymerase cleavages. Furthermore, cordycepin also induced the activation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase, and p38 MAPKs. Among MAPKs, activation of JNK solely contributed to cordycepin-induced apoptosis with the activation of caspase-8, caspase-9, and caspase-3 and cleavage of PARP. Taken together, the present study demonstrated that cordycepin activated JNK and caspase pathways to induce apoptosis in OEC-M1 cells.

In Silico Modeling Study of Curcumin Diffusion and Cellular Growth

Curcumin can enhance cutaneous wound healing by improving fibroblast proliferation. However, its therapeutic properties are dose-dependent: high concentrations produce cytotoxic effects, whereas low concentrations benefit cell proliferation. Similarly, the type of administration and its moderation are key aspects, as an erroneous distribution may result in null or noxious activity to the organism. In silico models for curcumin diffusion work as predictive tools for evaluating curcumin’s cytotoxic effects and establishing therapeutic windows. A 2D fibroblast culture growth model was created based on a model developed by Gérard and Goldbeter. Similarly, a curcumin diffusion model was developed by adjusting experimental release values obtained from Aguilar-Rabiela et al. and fitted to Korsmeyer–Peppas and Peleg’s hyperbolic models. The release of six key curcumin concentrations was achieved. Both models were integrated using Morpheus software, and a scratch-wound assay simulated curcumin’s dose-dependent effects on wound healing. The most beneficial effect was achieved at 0.25 μM, which exhibited the lowest cell-division period, the highest confluence (~60% for both release models, 447 initial cells), and the highest final cell population. The least beneficial effect was found at 20 μM, which inhibited cell division and achieved the lowest confluence (~34.30% for both release models, 447 initial cells). Confluence was shown to decrease as curcumin concentration increased, since higher concentrations of curcumin have inhibitory and cytotoxic effects.

Cytokines Activate JAK-STAT Signaling Pathway in MG-63 Cells on Titanium and Zirconia

Although titanium has been traditionally used as the gold standard for dental implants, recent years have seen the widespread application of zirconia implants given their superiority with regards to reduced bacterial adhesion, inflammation and cellular-interaction in terms of bio-compatibility. The JAK-STAT signaling pathway plays an important role in bone remodeling and formation. The aim of the study was to investigate the activation of the JAK-STAT pathway through different cytokines in osteoblast-like cells (MG-63) on zirconia in comparison to titanium discs. IFN-γ induced the very strong activation of STAT1 protein, IFN-α activated both STAT1 and STAT3 molecules, IL-6 activated STAT3 and IL-4 induced the activation of STAT6 on both surfaces. The activation of STAT proteins was confirmed by western blot, immunofluorescence and flow cytometry using phospho-specific anti-STAT antibodies, which recognize only phosphorylated STAT proteins. The incubation of MG-63 cells with IFN-γ caused the upregulation of MHC class I and class II proteins when MG-63 cells were grown on zirconia and titanium discs. In sum, the present study shows that the JAK-STAT pathway is activated in MG-63 cells when they are incubated on titanium or zirconia surfaces.

Curcumin attenuates Cr (VI)-induced cell growth and migration by targeting autophagy-dependent reprogrammed metabolism

Hexavalent chromium [Cr (VI)] is a well-established carcinogen. Cr (VI)-treated cells are phenotypically characterized by aberrant levels of growth and migration. Curcumin, a polyphenolic compound from the plant turmeric, has been found to possess antiproliferation, anti-inflammation, and antioxidant properties. In this study, the effect of curcumin on Cr (VI)-induced cell survival and migration and the underlying mechanism were investigated. Cell viability assay on A549 and human embryonic lung fibroblast cells showed that curcumin at the concentration of 10 µM could significantly attenuate Cr (VI)-induced viability in both cell lines. Following Western blot assay and metabolomics assays, cotreatment with curcumin and Cr (VI) resulted in the suppression of Cr (VI)-induced glycolysis-, autophagy-, and migration-related proteins. Meanwhile, curcumin increased Cr (VI)-reduced oxidative phosphorylation (OXPHOS)-related proteins, COXIV and ND1. Moreover, curcumin suppressed Cr (VI)-induced mitochondrial dysfunction, mitochondrial mass decrease, and mitochondrial membrane potential loss. Treatment with curcumin for 24 h significantly attenuated pcATG4B-induced autophagy and the subsequent expression of glucose transporter 1, hexokinase II, and pyruvate kinase M2. Wound healing and transwell assay demonstrated that curcumin reduced Cr (VI)-induced cell migration. Taken together, these results showed that curcumin was able to attenuate Cr (VI)-induced cell viability and migration by targeting autophagy-dependent reprogrammed metabolism from OXPHOS to glycolysis.

The Role of Natural Products and Their Multitargeted Approach to Treat Solid Cancer

Natural products play a critical role in the discovery and development of numerous drugs for the treatment of various types of cancer. These phytochemicals have demonstrated anti-carcinogenic properties by interfering with the initiation, development, and progression of cancer through altering various mechanisms such as cellular proliferation, differentiation, apoptosis, angiogenesis, and metastasis. Treating multifactorial diseases, such as cancer with agents targeting a single target, might lead to limited success and, in many cases, unsatisfactory outcomes. Various epidemiological studies have shown that the steady consumption of fruits and vegetables is intensely associated with a reduced risk of cancer. Since ancient period, plants, herbs, and other natural products have been used as healing agents. Likewise, most of the medicinal ingredients accessible today are originated from the natural resources. Regardless of achievements, developing bioactive compounds and drugs from natural products has remained challenging, in part because of the problem associated with large-scale sequestration and mechanistic understanding. With significant progress in the landscape of cancer therapy and the rising use of cutting-edge technologies, we may have come to a crossroads to review approaches to identify the potential natural products and investigate their therapeutic efficacy. In the present review, we summarize the recent developments in natural products-based cancer research and its application in generating novel systemic strategies with a focus on underlying molecular mechanisms in solid cancer.

HO-3867 Induces Apoptosis via the JNK Signaling Pathway in Human Osteosarcoma Cells

Metastatic osteosarcoma often results in poor prognosis despite the application of surgical en bloc excision along with chemotherapy. HO-3867 is a curcumin analog that induces cell apoptosis in several cancers, but the apoptotic effect and its mechanisms on osteosarcoma cells are still unknown. After observing the decrease in cellular viability of three human osteosarcoma U2OS, HOS, and MG-63 cell lines, and the induction of cellular apoptosis and arrest in sub-G1 phase in U2OS and HOS cells by HO-3867, the human apoptosis array showed that heme oxygenase (HO)-1 and cleaved caspase-3 expressions had significant increases after HO-3867 treatment in U2OS cells and vice versa for cellular inhibitors of apoptosis (cIAP)1 and X-chromosome-linked IAP (XIAP). Western blot analysis verified the results and showed that HO-3867 activated the initiators of both extrinsic caspase 8 and intrinsic caspase 9, and significantly increased cleaved PARP expression in U2OS and HOS cells. Moreover, with the addition of HO-3867, ERK1/2, and JNK1/2 phosphorylation were increased in U2OS and HOS cells. Using the inhibitor of JNK (JNK in 8), HO-3867’s increases in cleaved caspases 3, 8, and 9 could be expectedly suppressed, indicating that JNK signaling is responsible for both apoptotic pathways, including extrinsic and intrinsic, in U2OS and HOS cells caused by HO-3867. Through JNK signaling, HO-3867 has proven to be effective in causing both extrinsic and intrinsic apoptotic pathways of human osteosarcoma cells.

Robust radiosensitization of hemoglobin-curcumin nanoparticles suppresses hypoxic hepatocellular carcinoma

Background

Radioresistance inducing by hypoxic microenvironment of hepatocellular carcinoma is a major obstacle to clinical radiotherapy. Advanced nanomedicine provides an alternative to alleviate the hypoxia extent of solid tumor, even to achieve effective synergistic treatment when combined with chemotherapy or radiotherapy.

Results

Herein, we developed a self-assembled nanoparticle based on hemoglobin and curcumin for photoacoustic imaging and radiotherapy of hypoxic hepatocellular carcinoma. The fabricated nanoparticles inhibited hepatoma migration and vascular mimics, and enhanced the radiosensitivity of hypoxic hepatoma cells in vitro via repressing cell proliferation and DNA damage repair, as well as inducing apoptosis. Benefit from oxygen-carrying hemoglobin combined with polyphenolic curcumin, the nanoparticles also effectively enhanced the photoacoustic contrast and the efficacy of radiotherapy for hepatocellular carcinoma in vivo.

Conclusions

Together, the current study offered a radiosensitization platform for optimizing the efficacy of nanomedicines on hypoxic radioresistant tumor.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01316-w.

Astaxanthin ameliorates lipopolysaccharide-induced acute lung injury via inhibition of inflammatory reactions and modulation of the SOCS3/JAK2/STAT3 signaling pathways in mice

The results showed that astaxanthin had a protective effect on LPS-induced acute lung injury in mice, and its protective mechanism was through activating the SOCS3/JAK2/STAT3 signaling pathway.

Curculigoside Represses the Proliferation and Metastasis of Osteosarcoma via the JAK/STAT and NF-κB Signaling Pathways

Curculigoside (Cur) is a natural component from Curculigo orchioides Gaertn, with various bioactivities. The function of Cur in the nervous system and osteoarthritis has been reported. However, its role in osteosarcoma (OS) needs to be investigated. Hence, we focus on probing the impact of Cur on OS. In vitro, cell counting kit 8 (CCK-8), flow cytometry and Transwell assay were used to investigate the effects of Cur on OS cell proliferation, apoptosis, migration and invasion. In vivo, we developed a xenograft model to figure out the effect of Cur on tumor growth in nude mice. Western blotting (WB) was conducted to compare the levels of Cur on apoptosis-related proteins (C-caspase-3, Bax, and Bcl-2), epithelial-mesenchymal transition (EMT)-related proteins (N-cadherin, Snail, and E-cadherin) and the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) and nuclear factor-κB (NF-κB) pathways in vitro and in vivo. In-vitro data testified that Cur treatment markedly hampered OS cells' growth, migration and invasion and intensified their apoptosis compared to that of the control group. In vivo, Cur treatment notably hampered the growth of OS tumors in mice. In addition, both in vitro and in vivo experiments demonstrated that the phosphorylation of JAK2, STAT3, and NF-κB were inhibited through Cur treatment. Furthermore, the inhibition of Cur in OS cells was demonstrated by up-regulating the expression of JAK/STAT and NF-κB pathways protein levels. In summary, the data suggest that Cur curbs OS growth by down-regulating the JAK/STAT and NF-κB pathways, which is an underlying therapeutic option for OS treatment.

Receptor Tyrosine Kinases and Their Signaling Pathways as Therapeutic Targets of Curcumin in Cancer

Receptor tyrosine kinases (RTKs) are transmembrane cell-surface proteins that act as signal transducers. They regulate essential cellular processes like proliferation, apoptosis, differentiation and metabolism. RTK alteration occurs in a broad spectrum of cancers, emphasising its crucial role in cancer progression and as a suitable therapeutic target. The use of small molecule RTK inhibitors however, has been crippled by the emergence of resistance, highlighting the need for a pleiotropic anti-cancer agent that can replace or be used in combination with existing pharmacological agents to enhance treatment efficacy. Curcumin is an attractive therapeutic agent mainly due to its potent anti-cancer effects, extensive range of targets and minimal toxicity. Out of the numerous documented targets of curcumin, RTKs appear to be one of the main nodes of curcumin-mediated inhibition. Many studies have found that curcumin influences RTK activation and their downstream signaling pathways resulting in increased apoptosis, decreased proliferation and decreased migration in cancer both in vitro and in vivo. This review focused on how curcumin exhibits anti-cancer effects through inhibition of RTKs and downstream signaling pathways like the MAPK, PI3K/Akt, JAK/STAT, and NF-κB pathways. Combination studies of curcumin and RTK inhibitors were also analysed with emphasis on their common molecular targets.

Potential of natural products in osteosarcoma treatment: Focus on molecular mechanisms

Osteosarcoma is the most frequent type of bone cancer found in children and adolescents, and commonly arises in the metaphyseal region of tubular long bones. Standard therapeutic approaches, such as surgery, chemotherapy, and radiation therapy, are used in the management of osteosarcoma. In recent years, the mortality rate of osteosarcoma has decreased due to advances in treatment methods. Today, the scientific community is investigating the use of different naturally derived active principles against various types of cancer. Natural bioactive compounds can function against cancer cells in two ways. Firstly they can act as classical cytotoxic compounds by non-specifically affecting macromolecules, such as DNA, enzymes, and microtubules, which are also expressed in normal proliferating cells, but to a greater extent by cancer cells. Secondly, they can act against oncogenic signal transduction pathways, many of which are activated in cancer cells. Some bioactive plant-derived agents are gaining increasing attention because of their anti-cancer properties. Moreover, some naturally-derived compounds can significantly promote the effectiveness of standard chemotherapy drugs, and in certain cases are able to ameliorate drug-induced adverse effects caused by chemotherapy. In the present review we summarize the effects of various naturally-occurring bioactive compounds against osteosarcoma.

The Multifaceted Therapeutic Mechanisms of Curcumin in Osteosarcoma: State-of-the-Art

Osteosarcoma is a major form of malignant bone tumor that typically occurs in young adults and children. The combination of aggressive surgical strategies and chemotherapy has led to improvements in survival time, although individuals with recurrent or metastatic conditions still have an extremely poor prognosis. This disappointing situation strongly indicates that testing novel, targeted therapeutic agents is imperative to prevent the progression of osteosarcoma and enhance patient survival time. Curcumin, a naturally occurring phenolic compound found in Curcuma longa, has been shown to have a wide variety of anti-tumor, anti-oxidant, and anti-inflammatory activities in many types of cancers including osteosarcoma. Curcumin is a highly pleiotropic molecule that can modulate intracellular signaling pathways to regulate cell proliferation, inflammation, and apoptosis. These signaling pathways include RANK/RANKL, Notch, Wnt/β-catenin, apoptosis, autophagy, JAK/STAT, and HIF-1 pathways. Additionally, curcumin can regulate the expression of various types of microRNAs that are involved in osteosarcoma. Therefore, curcumin may be a potential candidate for the prevention and treatment of osteosarcoma. This comprehensive review not only covers the use of curcumin in the treatment of osteosarcoma and its anti-cancer molecular mechanisms but also reveals the novel delivery strategies and combination therapies with the aim to improve the therapeutic effect of curcumin.

Assessing a Novel 3D Assay System for Drug Screening against OS Metastasis

Osteosarcoma (OS) is an aggressive mesenchymal cell tumor that carries a poor long-term prognosis. Despite definitive surgery for the primary tumor and adjuvant chemotherapy, pulmonary metastasis is common and is the primary cause of morbidity. To improve outcomes for patients, we have developed and optimized a phenotypic screen for drugs that may target OS disseminated tumor cells (DTCs) and inhibit their metastatic outbreak rather than merely screening for cytotoxic activity against proliferating cells, as is commonly conducted in conventional drug discovery approaches. We report on the validation of a previously described 3D reconstituted basement membrane extract (3D BME) model system for tumor dormancy and metastatic outgrowth adapted to clonal pairs of high and low metastatic OS cells. A post-hoc validation of the assay was possible by comparing the activity of a drug in our assay with early evidence of activity in human OS clinical trials (regorafenib and saracatinib). In this validation, we found concordance between our assay and human clinical trial experience We then explored an approved veterinary small molecule inhibitor of Janus kinase-1 (oclacitinib) as a potential drug candidate to take advantage of the high prevalence of OS in pet dogs and its translational value to humans. Despite the biological rationale, we found no evidence to support the use of oclacitinib as an antimetastatic agent in OS. The findings support our 3D BME assay as a highly efficient method to examine drugs for activity in targeting OS DTCs.

Curcumin suppresses the progression of gastric cancer by regulating circ_0056618/miR-194-5p axis

Curcumin has been demonstrated to be an anti-tumor agent in many types of cancers, including gastric cancer (GC). However, the molecular mechanisms by which curcumin performs its anti-tumor effects remain elusive. circ_0056618 and miR-194-5p are reported to be involved in GC progression, but their relationships with curcumin are unclear. In this study, circ_0056618 was elevated, and miR-194-5p was reduced in GC tissues and cells. Curcumin treatment led to a decrease in circ_0056618 level in GC cells. Overexpression of circ_0056618 promoted cell proliferation, migration, and invasion and suppressed cell cycle arrest and apoptosis in curcumin-treated GC cells. Moreover, miR-194-5p was identified as the target of circ_0056618, and its expression in GC cells increased after curcumin treatment. Overexpression of miR-194-5p reversed the promotional effect of circ_0056618 on cell progression in curcumin-treated GC cells. Additionally, curcumin treatment repressed the tumorigenesis of GC in vivo through regulating circ_0056618. Curcumin treatment delayed the development of GC partly through decreasing circ_0056618 and increasing miR-194-5p.

Pharmacological Effects of Polyphenol Phytochemicals on the JAK-STAT Signaling Pathway

The JAK-STAT signaling pathway is a common pathway of many cytokine signal transductions, closely related to cell proliferation, apoptosis, differentiation, and inflammatory response. It is essential for inhibiting the inflammatory response, initiating innate immunity, and coordinating adaptive immune mechanisms. Owing to the nature of this pathway and its potential cross-epitopes with multiple alternative pathways, the long-term efficacy of monotherapy-based adaptive targeting therapy is limited, and the majority of drugs targeting STATs are still in the preclinical phase. Meanwhile, curcumin, quercetin, and several kinds of plant polyphenol chemicals play roles in multiple sites of the JAK-STAT pathway to suppress abnormal activation. Polyphenol compounds have shown remarkable effects by acting on the JAK-STAT pathway in anti-inflammatory, antitumor, and cardiovascular disease control. This review summarizes the pharmacological effects of more than 20 kinds of phytochemicals on JAK-STAT signaling pathway according to the chemical structure of polyphenolic phytochemicals.

GO-Y078, a Curcumin Analog, Induces Both Apoptotic Pathways in Human Osteosarcoma Cells via Activation of JNK and p38 Signaling

Osteosarcoma is the most common primary bone malignancy in teenagers and continues to confer a generally poor prognosis due to its highly metastatic potential. Poor solubility in water and instability of curcumin limits its bioavailability for use in the adjuvant situation to improve the prognosis and the long-term survival of patients with osteosarcoma. To further obtain information regarding the apoptosis induced by a new curcumin analog, GO-Y078, in human osteosarcoma cells, flow cytometric analysis, annexin V-FITC/PI apoptosis staining assay, human apoptosis array, and Western blotting were employed. GO-Y078 dose-dependently decreased viabilities of human osteosarcoma U2OS, MG-63, 143B, and Saos-2 cells and induced sub-G1 fraction arrest and apoptosis in U2OS and 143B cells. In addition to the effector caspase 3 and poly adenosine diphosphate-ribose polymerase, GO-Y078 significantly activated both initiators of extrinsic caspase 8 and intrinsic caspase 9, whereas cellular inhibitors of apoptosis 1 (cIAP-1) and X-chromosome-linked IAP (XIAP) in U2OS and 143B cells were significantly repressed. Moreover, GO-Y078 increased phosphorylation of extracellular signal-regulated protein kinases (ERK)1/2, c-Jun N-terminal kinases (JNK)1/2, and p38 in U2OS and 143B cells. Using inhibitors of JNK (JNK-in-8) and p38 (SB203580), GO-Y078′s increases in cleaved caspases 8, 9, and 3 could be expectedly suppressed, but they could not be affected by co-treatment with the ERK inhibitor (U0126). Altogether, GO-Y078 simultaneously induces both apoptotic pathways and cell arrest in U2OS and 143B cells through activating JNK and p38 signaling and repressing IAPs. These findings contribute to a better understanding of the mechanisms responsible for GO-Y078′s apoptotic effects on human osteosarcoma cells.

Curcumin in Osteosarcoma Therapy: Combining With Immunotherapy, Chemotherapeutics, Bone Tissue Engineering Materials and Potential Synergism With Photodynamic Therapy

Osteosarcoma is a dominating malignant bone tumor with high mortality due to pulmonary metastases. Furthermore, because of the cancer cell erosion and surgery resection, osteosarcoma always causes bone defects, which means dysfunction and disfigurement are seldom inevitable. Although various advanced treatments (e.g. chemotherapy, immunotherapy, radiotherapy) are coming up, the 5-year survival rate for osteosarcoma with metastases is still dismal. In line with this, the more potent treatments for osteosarcoma are in high demand. Curcumin, a perennial herb, has been reportedly applied in the therapy of various types of tumors via different mechanisms. In vitro, it has also been reported that curcumin can inhibit the proliferation of osteosarcoma cell lines and can be used to repair bone defects. This seems curcumin is a promising candidate in osteosarcoma treatment. However, due to its congenital property like hydrophobicity, and low bioavailability, affecting its anticancer effect, clinical applications of curcumin are highly limited. To enhance its performance in cancer therapies, some synergist approaches with curcumin have emerged. The present review presents some prospective ones (i.e. combinations with immunotherapy, chemotherapeutics, bone tissue engineering, and biomaterials) applied in osteosarcoma treatment. Additionally, with the advancements of photodynamic therapy in cancer therapy, this review also prospects the combination of curcumin with photodynamic therapy in osteosarcoma treatment.

Diabetes and Cancer: Metabolic Association, Therapeutic Challenges, and the Role of Natural Products

Cancer is considered the second leading cause of death worldwide and in 2018 it was responsible for approximately 9.6 million deaths. Globally, about one in six deaths are caused by cancer. A strong correlation was found between diabetes mellitus and carcinogenesis with the most evident correlation was with type 2 diabetes mellitus (T2DM). Research has proven that elevated blood glucose levels take part in cell proliferation and cancer cell progression. However, limited studies were conducted to evaluate the efficiency of conventional therapies in diabetic cancer patients. In this review, the correlation between cancer and diabetes will be discussed and the mechanisms by which the two diseases interact with each other, as well as the therapeutics challenges in treating patients with diabetes and cancer with possible solutions to overcome these challenges. Natural products targeting both diseases were discussed with detailed mechanisms of action. This review will provide a solid base for researchers and physicians to test natural products as adjuvant alternative therapies to treat cancer in diabetic patients.

STAT3 and its targeting inhibitors in osteosarcoma

Signal transducer and activator of transcription 3 (STAT3) is one of seven STAT family members involved with the regulation of cellular growth, differentiation and survival. STAT proteins are conserved among eukaryotes and are important for biological functions of embryogenesis, immunity, haematopoiesis and cell migration. STAT3 is widely expressed and located in the cytoplasm in an inactive form. STAT3 is rapidly and transiently activated by tyrosine phosphorylation by a range of signalling pathways, including cytokines from the IL‐6 family and growth factors, such as EGF and PDGF. STAT3 activation and subsequent dimer formation initiates nuclear translocation of STAT3 for the regulation of target gene transcription. Four STAT3 isoforms have been identified, which have distinct biological functions. STAT3 is considered a proto‐oncogene and constitutive activation of STAT3 is implicated in the development of various cancers, including multiple myeloma, leukaemia and lymphomas. In this review, we focus on recent progress on STAT3 and osteosarcoma (OS). Notably, STAT3 is overexpressed and associated with the poor prognosis of OS. Constitutive activation of STAT3 in OS appears to upregulate the expression of target oncogenes, leading to OS cell transformation, proliferation, tumour formation, invasion, metastasis, immune evasion and drug resistance. Taken together, STAT3 is a target for cancer therapy, and STAT3 inhibitors represent potential therapeutic candidates for the treatment of OS.

Curcumin Analogue L48H37 Suppresses Human Osteosarcoma U2OS and MG-63 Cells' Migration and Invasion in Culture by Inhibition of uPA via the JAK/STAT Signaling Pathway

Osteosarcoma, the most prevalent malignant bone tumor in the pediatric age group, is responsible for the great majority of cancer-associated deaths owing to its highly metastatic potential. The anti-metastatic effects of the new curcumin analogue L48H37 in human osteosarcoma are still unknown; hence, we investigated whether L48H37 represses human osteosarcoma cells’ biological behavior of migratory potential and invasive activities and attempted to delve into its underlying mechanisms. L48H37 up to 5 μM inhibited, without cytotoxicity, the motility, migration, and invasion of human osteosarcoma U2OS and MG-63 cells. In U2OS cells, the human protease array revealed an obvious decrease in urokinase plasminogen activator (uPA) expression after L48H37 treatment, and L48H37 actually reduced the level, protein and mRNA expression, and promoter activity of uPA dose-dependently. L48H37 decreased the phosphorylation of STAT3, JAK1, JAK2, and JAK3 in U2OS cells, but did not affect the phosphorylation of ERK, JNK, p38, and Akt. Using colivelin, an activator of STAT3, the L48H37-induced decrease in uPA and migratory potential could be countered as expected. Collectively, L48H37 represses the invasion and migration capabilities of U2OS and MG-63 cells by the suppression of uPA expression and the inhibition of JAK/STAT signaling. These results suggest that L48H37 may be a potential candidate for anti-metastatic treatment of human osteosarcoma.

Progress in Natural Compounds/siRNA Co-delivery Employing Nanovehicles for Cancer Therapy

Chemotherapy using natural compounds, such as resveratrol, curcumin, paclitaxel, docetaxel, etoposide, doxorubicin, and camptothecin, is of importance in cancer therapy because of the outstanding therapeutic activity and multitargeting capability of these compounds. However, poor solubility and bioavailability of natural compounds have limited their efficacy in cancer therapy. To circumvent this hurdle, nanocarriers have been designed to improve the antitumor activity of the aforementioned compounds. Nevertheless, cancer treatment is still a challenge, demanding novel strategies. It is well-known that a combination of natural products and gene therapy is advantageous over monotherapy. Delivery of multiple therapeutic agents/small interfering RNA (siRNA) as a potent gene-editing tool in cancer therapy can maximize the synergistic effects against tumor cells. In the present review, co-delivery of natural compounds/siRNA using nanovehicles are highlighted to provide a backdrop for future research.

Plant-Derived Natural Products in Cancer Research: Extraction, Mechanism of Action, and Drug Formulation

Cancer is one of the main causes of death globally and considered as a major challenge for the public health system. The high toxicity and the lack of selectivity of conventional anticancer therapies make the search for alternative treatments a priority. In this review, we describe the main plant-derived natural products used as anticancer agents. Natural sources, extraction methods, anticancer mechanisms, clinical studies, and pharmaceutical formulation are discussed in this review. Studies covered by this review should provide a solid foundation for researchers and physicians to enhance basic and clinical research on developing alternative anticancer therapies.

Potential therapeutic effects of curcumin mediated by JAK/STAT signaling pathway: A review

Curcumin is a naturally occurring nutraceutical compound with a number of therapeutic and biological activities such as antioxidant, anti-inflammatory, anti-diabetic, antitumor, and cardioprotective. This plant-derived chemical has demonstrated great potential in targeting various signaling pathways to exert its protective effects. Signal transducers and activator of transcription (STAT) is one of the molecular pathways involved in a variety of biological processes such as cell proliferation and cell apoptosis. Accumulating data demonstrates that the STAT pathway is an important target in treatment of a number of disorders, particularly cancer. Curcumin is capable of affecting STAT signaling pathway in induction of its therapeutic impacts. Curcumin is able to enhance the level of anti-inflammatory cytokines and improve inflammatory disorders such as colitis by targeting STAT signaling pathway. Furthermore, studies show that inhibition of JAK/STAT pathway by curcumin is involved in reduced migration and invasion of cancer cells. Curcumin normalizes the expression of JAK/STAT signaling pathway to exert anti-diabetic, renoprotective, and neuroprotective impacts. At the present review, we provide a comprehensive discussion about the effect of curcumin on JAK/STAT signaling pathway to direct further studies in this field.

Curcumin Derivative C086 Combined with Cisplatin Inhibits Proliferation of Osteosarcoma Cells

Background

Curcumin derivative C086 (cur C086) is a potential chemotherapeutic agent for patients with osteosarcoma. In this study, the effects of cur C086 combined with cisplatin on the biological processes of osteosarcoma cells were investigated.

Material/Methods

In this study, expression of BMIL1 was detected by real-time quantitative reverse transcription polymerase chain reaction and Western blotting in MG-63 cells treated with cur C086+cisplatin. Functions of cur C086+cisplatin on proliferation ability, apoptosis response, and metastatic potential of MG-63 cells were determined by MTT, flow cytometry, Hoechst 33258 staining and Transwell assays, respectively. In additionally, expression of P16, E-cadherin, epidermal growth factor (EGFR), and Notch1 was measured by Western blotting.

Results

Expression of BMIL1 decreased significantly in MG-63 cells treated with cur C086 (20 μM)+cisplatin (1.28 nM). Treatment with cur C086+cisplatin considerably inhibited growth, migration, and invasion potential in MG-63 cells, whereas apoptosis was obviously upregulated. Moreover, cur C086+cisplatin suppressed BMIL1 expression or its potential downstream targets, P16, E-cadherin, EGFR, and Notch1.

Conclusions

The current results demonstrate that combined treatment with cur C086+cisplatin may be an effective form of chemotherapy for patients with osteosarcoma.

Phytochemical Targeting of STAT3 Orchestrated Lipid Metabolism in Therapy-Resistant Cancers

Lipids are critical for maintaining homeostasis and cellular metabolism. However, the dysregulation of lipid metabolism contributes to the pathogenesis of chronic inflammatory diseases and is a hallmark of several cancer types. Tumours exist in a microenvironment of poor vascularization-depleted oxygen and restricted nutrients. Under these conditions, tumours have been shown to increasingly depend on the metabolism of fatty acids for sustained proliferation and survival. Signal transducer and activator of transcription 3 (STAT3) plays a key role in cellular processes such as cell growth, apoptosis and lipid metabolism. Aberrant STAT3 activity, as seen in several cancer types, is associated with tumour progression and malignancy, in addition to propagating crosstalk between tumour cells and the microenvironment. Furthermore, STAT3-regulated lipid metabolism is critical for cancer stem cell self-renewal and therapy resistance. Plant-derived compounds known as phytochemicals are a potential source for novel cancer therapeutic drugs. Dietary phytochemicals are known to modulate key cellular signalling pathways involved in lipid homeostasis and metabolism, including the STAT3 signalling pathways. Targeting STAT3 orchestrated lipid metabolism has shown therapeutic promise in human cancer models. In this review, we summarize the antitumour activity of phytochemicals with an emphasis placed on their effect on STAT3-regulated lipid metabolism and their role in abrogating therapy resistance.

The roles of curcumin in regulating the tumor immunosuppressive microenvironment

Cancer is a harmful threat to human health. In addition to surgery, a variety of anticancer drugs are increasingly used in cancer therapy; however, despite the developments in multimodality treatment, the morbidity and mortality of patients with cancer patients are on the increase. The tumor-specific immunosuppressive microenvironment serves an important function in tumor tolerance and escape from immune surveillance leading to tumor progression. Therefore, identifying new drugs or foods that can enhance the tumor immune response is critical to develop improved cancer prevention methods and treatment. Curcumin, a polyphenolic compound extracted from ginger, has been shown to effectively inhibit tumor growth, proliferation, invasion, metastasis and angiogenesis in a variety of tumors. Recent studies have also indicated that curcumin can modulate the tumor immune response and remodel the tumor immunosuppressive microenvironment, indicating its potential in the immunotherapy of cancer. In this review, a brief introduction to the effects of curcumin on the tumor immune response and tumor immune microenvironment is provided and recent clinical trials investigating the potential of curcumin in cancer therapy are discussed.

Curcumin Inhibits the Tumorigenesis of Breast Cancer by Blocking Tafazzin/Yes-Associated Protein Axis

Purpose

This study was aimed to explore the anti-tumor effect of curcumin on breast cancer (BC) and the underlying mechanism involving Tafazzin (TAZ)/Yes-associated protein (YAP) axis.

Methods

Different concentrations of curcumin (0, 10, 20 and 30 μM) were used to treat BC cells (MCF-7 and MDA-MB-231 cells). The viability, colony formation, apoptosis, migration, and invasion of BC cells were detected by MTT, colony formation, flow cytometry, wound-healing and transwell assay, respectively. The protein expression of TAZ and YAP (effectors of Hippo signaling pathway) was detected by Western blot. MDA-MB-231 cells were injected into mice to verify the anti-tumor effect of curcumin in vivo.

Results

Curcumin (20 and 30 μM) inhibited the proliferation, migration and invasion, and promoted the apoptosis of MCF-7 and MDA-MB-231 cells. Curcumin decreased the protein expression of TAZ and YAP in MCF-7 and MDA-MB-231 cells. Overexpression of YAP reversed the anti-tumor effect of curcumin on MDA-MB-231 cells. In addition, curcumin (100, 200 and 300 mg/kg/d) inhibited the growth of tumor xenografts in mice, and down-regulated the protein expression of TAZ and YAP in tumor xenografts. However, curcumin at a concentration of 300 mg/kg/d slowed the increasing of body weight in mice.

Conclusion

Curcumin inhibited the tumorigenesis of BC by blocking TAZ/YAP axis.

Aloin Inhibits the Proliferation and Migration of Gastric Cancer Cells by Regulating NOX2-ROS-Mediated Pro-Survival Signal Pathways

Background

Aloin has been reported to have many pharmacological effects including anti-inflammatory, anti-oxidant and anti-tumour activities. However, the precise molecular mechanisms underlying the anti-tumour properties of aloin are yet to be elucidated.

Methods

HGC-27 and BGC-823 gastric cancer cells were treated with aloin. EdU and colony formation assays were used to detect the proliferation ability of cells. The migration of cells was detected using wound healing and transwell assays. Western blotting was used to detect the levels of cyclinD1, cyclin E1, MMPs, N-cadherin, E-cadherin and NOX2. The phosphorylation of Akt, mTOR, P70S6K, S6, Src, stat3 and IκBα were also detected by Western blotting. Flow cytometry was used to detect the cell cycle distribution.The location of p65 in cells was determined by using a confocal microscopy assay. The total amounts of ROS present in cells were measured using an ROS assay kit.

Results

Here, we found that aloin inhibited the proliferation and migration of HGC-27 and BGC-823 gastric cancer cells using a combination of EdU, colony formation, wound healing and transwell assays. Further investigations revealed that aloin decreased the protein expression levels of cyclin D1, N-cadherin, and the matrix metalloproteinases (MMP)-2 and MMP-9; increased E-cadherin expression in a dose-dependent manner; inhibited reactive oxygen species (ROS) generation; and mediated the activation of Akt-mTOR, signal transducer and activator of transcription-3 (Stat3), and NF-κB signalling pathways. Our results also indicated that aloin is able to attenuate the expression levels of the two regulatory proteins of nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2), p47^phox and p22^phox, but had no effect on the level of gp91^phox. N-acetylcysteine treatment of gastric cancer cells inhibited ROS production and Akt-mTOR, Stat3, and IκBα phosphorylation. Taken together, our data suggest that aloin inhibits the proliferation and migration of gastric cancer cells by downregulating NOX2–ROS-mediated activation of the Akt-mTOR, Stat3, and NF-κB signalling pathways.

Conclusion

Our findings suggest a potential role for aloin in the prevention of gastric cancer cell proliferation and migration and provide novel insights into the anti-cancer properties of aloin.

Curcumin Management of Myocardial Fibrosis and its Mechanisms of Action: A Review

Myocardial fibrosis is implicated as a leading risk factor for heart failure, arrhythmia, and sudden death after cardiac injury, as the excessive interstitial extracellular matrix impedes heart contraction and electrical conduction. Complicated mechanisms involving oxidative stress, pro-inflammatory cytokines, chemokine families, NLRP3 inflammasomes, growth factors, and non-coding RNAs participate in cardiac fibrogenesis and make it difficult to designate specific and effective therapies. Oriental herbs have been popular for thousands of years in the health care of Asian residents, due to their multi-targeted, multi-faceted approaches and their multi-functional effects in fighting difficult and complicated diseases, including cardiovascular disorders such as myocardial fibrosis. Curcumin, a natural polyphenol and yellow pigment obtained from the spice turmeric, was found to have strong anti-oxidant and anti-inflammatory properties. Increasing evidence has shown that curcumin can be used to prevent and treat myocardial fibrosis, when the myocardium suffers pathological pro-fibrotic changes in vivo and in vitro. The present review focuses on recent studies elucidating the mechanisms of curcumin in treating different pathologic conditions, including ischemia, hypoxia/reoxygenation, pressure or volume overload, and hyperglycemia or high-fat-induced cardiac fibrosis. Novel analogs such as C66, B2BrBC, Y20, and J17 have been designed to maximize the therapeutic potentials of curcumin. These optimized curcumin analogs with improved bioavailability and pharmacokinetic profiles need to be clinically verified before curcumin could be recommended for the treatment of myocardial fibrosis.