Curcumin on the "flying carpets" to modulate different signal transduction cascades in cancers: Next-generation approach to bridge translational gaps

Curcumin Modulates Oxidative Stress, Fibrosis, and Apoptosis in Drug-Resistant Cancer Cell Lines

In cancer management, drug resistance remains a challenge that reduces the effectiveness of chemotherapy. Several studies have shown that curcumin resensitizes cancer cells to chemotherapeutic drugs to overcome resistance. In the present study, we investigate the potential therapeutic role of curcumin in regulating the proliferation of drug-resistant cancers. Six drug-sensitive (MCF7, HCT116, and A549) and -resistant (MCF7/TH, HCT116R, and A549/ADR) cancer cell lines were treated with curcumin followed by an analysis of cytotoxicity, LDH enzyme, total reactive oxygen species, antioxidant enzymes (SOD and CAT), fibrosis markers (TGF-β1 protein, fibronectin, and hydroxyproline), and expression of cellular apoptotic markers (Bcl-2, Bax, Bax/Bcl-2 ratio, Annexin V, cytochrome c, and caspase-8). Additionally, the expression of cellular SIRT1 was estimated by ELISA and RT-PCR analysis. Curcumin treatment at doses of 2.7–54.3 µM significantly reduced the growth of sensitive and resistant cells as supported with decreased viability and increased cellular LDH enzyme of treated cells compared to controls non-treated cells. Curcumin also at doses of 2.7 and 54.3 µM regulated the fibrogenesis by reducing the expression of fibrotic markers in treated cells. Analysis of apoptotic markers indicated increased Bax, Bax, Bax/Bcl-2 ratio, Annexin V, caspase-8, and cytochrome c expression, while Bcl-2 expressions were significantly reduced. In curcumin-treated cells at 2.7 μM, non-significant change in ROS with significant increase in SOD and CAT activity was observed, whereas an increase in ROS with a reduction in respective antioxidant enzymes were seen at higher concentrations along with significant upregulation of SIRT1. In conclusion, the present study shows that curcumin induces anticancer activity against resistant cancer cell lines in a concentration- and time-dependent manner. The protective activities of curcumin against the growth of cancer cells are mediated by modulating oxidative stress, regulating fibrosis, SIRT1 activation, and inducing cellular apoptosis. Therefore, curcumin could be tested as an auxiliary therapeutic agent to improve the prognosis in patients with resistant cancers.

Preparation and evaluation of the anti-cancer properties of RGD-modified curcumin-loaded chitosan/perfluorohexane nanocapsules in vitro

Curcumin (Cur) encapsulation in nanocapsules (NCs) could improve its availability and therapeutic antitumor efficacy. Cur-loaded chitosan/perfluorohexane (CS/PFH) nanocapsules (CS/PFH-Cur-NCs) were thus synthesized via a nanoemulsion process. To further enhance the selective tumor targeting ability of Cur-loaded NCs, a novel CS/PFH-Cur-NCs with conjugation of Arg-Gly-Asp (RGD) peptide (RGD-CS/PFH-Cur-NCs) were prepared in this study. The properties of these NCs were then explored through in vitro release experiments and confocal laser scanning microscopy-based analyses of the ability of these NCs to target MDA-MB-231 breast cancer cells. In addition, an MTT assay-based approach was used to compare the relative cytotoxic impact of CS/PFH-Cur-NCs and RGD-CS/PFH-Cur-NCs on these breast cancer cells. It was found that both CS/PFH-Cur-NCs and RGD-CS/PFH-Cur-NCs were smooth, relatively uniform, spheroid particles, with the latter being 531.20 ± 68.97 nm in size. These RGD-CS/PFH-Cur-NCs can be ideal for contrast imaging studies, and were better able to target breast cancer cells in comparison to CS/PFH-Cur-NCs. In addition, RGD-CS/PFH-Cur-NCs were observed to induce cytotoxic MDA-MB-231 cell death more swiftly in comparison to CS/PFH-Cur-NCs. These findings suggest that NC encapsulation and RGD surface modification can remarkably improve the anti-tumor efficacy of Cur. These novel NCs may thus manifest a significant potential value in the realm of image-guided cancer therapy, underscoring an important direction for future research.

Curcumin, the active substance of turmeric: its effects on health and ways to improve its bioavailability

Turmeric (Curcuma longa L.) is a spice utilized widely in India, China, and Southeast Asia as an aromatic stimulant, a food preservative, and coloring material. The commonly used names of turmeric are castor saffron, turmeric, and saffron root. Turmeric is a yellow-orange polyphenolic natural substance derived from C. longa rhizomes. It has been used to treat common inflammatory diseases, tumors, biliary diseases, anorexia, cough, topical wounds, diabetic injuries, liver disorders, rheumatism, and sinusitis. Extensive studies on the biological properties and pharmacological consequences of turmeric extracts have been conducted in recent years. Curcumin, the primary yellow biocomponent of turmeric, has anti-inflammatory, antioxidant, anticarcinogenic, antidiabetic, antibacterial, antiprotozoal, antiviral, antifibrotic, immunomodulatory, and antifungal properties. Defense assessment tests showed that curcumin is tolerated well at high doses, without adverse effects. Thus, curcumin is a highly active biological material with the potential to treat different diseases in modern medicine. This review article focuses on curcumin's biological characteristics. The most popular methods for curcumin encapsulation are also discussed. Several effective techniques and approaches have been proposed for curcuminoid capsulation, including nanocomplexing, gelation, complex coacervation, electrospraying, and solvent-free pH-driven encapsulation. This review also highlights curcumin's chemical properties, allowing the readers to expand their perspectives on its use in the development of functional products with health-promoting properties. © 2021 Society of Chemical Industry.

Anti-proliferative and apoptotic effect of gemini curcumin in p53-wild type and p53-mutant colorectal cancer cell lines

BACKGROUND

Despite recent advances in therapy, colorectal cancer remains a leading cause of death in affected people. Curcumin is the main bioactive compound of turmeric that has been demonstrated as an effective agent against cancer. However, its poor stability and bioavailability limit therapeutic application. We previously showed that delivery of curcumin by using gemini surfactant nanoparticles called gemini curcumin (Gemini-Cur) could improve its solubility, uptake and toxic effect on breast and ovarian cancer cells. Here, we aimed to investigate the anticancer activity of Gemini-Cur in both p53-mutant and p53-wild type colorectal cancer cells. The toxicity of Gemini-Cur on HT-29 and HCT116 was studied through MTT, uptake kinetics, fluorescence microscopy, annexin V/FITC, and cell cycle assays. Also, real-time PCR and western blotting were performed to evaluate the expression of p53, p21, BAX, BCL-2, and NOXA genes. Our data showed that Gemini-Cur not only enters cells quite rapidly compared to free curcumin crystals, but also suppresses HT-29 and HCT-116 cells proliferation in a time- and dose-dependent manner (p < 0.001). The IC50 values as well as apoptosis assays showed that p53-wild type cells are sensitive to Gemini-Cur. Flow cytometry also revealed that the number of apoptotic cells is dramatically increased in HCT-116 cells earlier than HT-29 cells (p < 0.0001). Gemini-Cur upregulated apoptotic genes including p53 (in both mutant and wild-type forms), p21, NOXA and BAX while decreased anti-apoptotic BCL-2 in mRNA and protein level (p < 0.0001). As a hallmark of apoptosis, the expression ratio of BAX/BCL-2 was significantly increased in all treated cells. Taken together, our findings demonstrated that Gemini-Cur suppresses the proliferation of cancer cells via induction of apoptosis and could be considered as novel nano-formulated phytochemical for cancer targeting.

Toward Regulatory Effects of Curcumin on Transforming Growth Factor-Beta Across Different Diseases: A Review

Immune response, proliferation, migration and angiogenesis are juts a few of cellular events that are regulated by transforming growth factor-β (TGF-β) in cells. A number of studies have documented that TGF-β undergoes abnormal expression in different diseases, e.g., diabetes, cancer, fibrosis, asthma, arthritis, among others. This has led to great fascination into this signaling pathway and developing agents with modulatory impact on TGF-β. Curcumin, a natural-based compound, is obtained from rhizome and roots of turmeric plant. It has a number of pharmacological activities including antioxidant, anti-inflammatory, anti-tumor, anti-diabetes and so on. Noteworthy, it has been demonstrated that curcumin affects different molecular signaling pathways such as Wnt/β-catenin, Nrf2, AMPK, mitogen-activated protein kinase and so on. In the present review, we evaluate the potential of curcumin in regulation of TGF-β signaling pathway to corelate it with therapeutic impacts of curcumin. By modulation of TGF-β (both upregulation and down-regulation), curcumin ameliorates fibrosis, neurological disorders, liver disease, diabetes and asthma. Besides, curcumin targets TGF-β signaling pathway which is capable of suppressing proliferation of tumor cells and invading cancer cells.

Using the Pleiotropic Characteristics of Curcumin to Validate the Potential Application of a Novel Gene Expression Screening Platform

Curcumin is a polyphenol derived from curcumin longa that exhibits anticancer and anti-inflammatory properties. The consumption of foods at supernutritional levels to obtain health benefits may paradoxically result in negative health outcomes. In the present study, multiple targeting characteristics of curcumin were analyzed using our gene expression screening system, which utilized the gene expression signatures of curcumin from human hepatocellular carcinoma and colorectal cancer cells to query gene expression databases and effectively identify the molecular actions of curcumin. In agreement with prediction, curcumin inhibited NF-κB and Aurora-A, and induced G2/M arrest and apoptosis. Curcumin-suppressed NF-κB was identified through inhibition of PLCG1, PIK3R1, and MALT1 in the CD4-T-cell-receptor-signaling NF-κB cascade pathway. The results suggest that our novel gene expression screening platform is an effective method of rapidly identifying unknown biological functions and side effects of compounds with potential nutraceutical benefits.

Development of curcumin-loaded gemini surfactant nanoparticles: Synthesis, characterization and evaluation of anticancer activity against human breast cancer cell lines

BACKGROUND

Curcumin, the polyphenolic constituent of turmeric, has been recognized as an effective anticancer agent in the treatment of breast cancer. However, the poor bioavailability of curcumin triggers finding of new approaches for elevating its therapeutic efficiency.

PURPOSE

We aimed to use gemini surfactant nanocarriers for curcumin in order to overcome its limitations.

STUDY DESIGN

We investigated the in vitro characterization of gemini surfactant-curcumin (Gemini-Cur) and examined its antiproliferative & apoptotic activities on breast cancer cell lines.

METHODS

Gemini-Cur polymersomes were synthesized through nanoprecipitation method and characterized by dynamic light scattering (DLS), transmission and scanning electron microscopies, HPLC and X-ray diffraction (XRD). The anticancer effect of Gemini-Cur nanoparticles was studied on three different breast cancer cell lines including MCF-7, SkBr-3 and MDA-MB-231 through uptake kinetics, viability & cytotoxicity recordings and apoptotic assays. Furthermore, qRT-PCR was performed to evaluate the expression of apoptotic genes including p16INK4a, p14ARF, Bax and Bcl-2.

RESULTS

According to physicochemical analysis, the average particle size, zeta potential value and drug entrapment efficiency for Gemini-Cur compound were recorded as 161 ± 6.2 nm, +5.32 mV and 89.13% ± 0.93, respectively. XRD analysis also confirmed the incorporation of curcumin in gemini surfactant micelles. Regarding the enhanced cellular uptake of sphere shaped Gemini-Cur, our data showed that this nano compound suppresses cancer cell proliferation via induction of apoptosis. Moreover, qRT-PCR analysis revealed that Gemini-Cur could effectively upregulate the expression of p16INK4a, p14ARF and Bax, while significantly decreasing the Bcl-2 expression in these breast cancer cells.

CONCLUSION

Our data demonstrates the great potential of gemini surfactants for efficient delivery of curcumin and subsequently, the improvement of its anticancer effect. Therefore, it is sagacious to support the idea that Gemini-Cur nano compound might have the potential to be considered as an anticancer agent.

Wenshen Zhuanggu formula mitigates breast cancer bone metastasis through the signaling crosstalk among the Jagged1/Notch, TGF-β and IL-6 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Advanced breast cancer frequently metastasizes to the bone, resulting in patient morbidity and mortality. The interaction of tumor cells with osteoclasts and osteoblasts seriously affects the occurrence and development of bone metastasis in breast cancer. The signaling crosstalk among the Jagged1/Notch, TGF-β and IL-6 signaling pathways plays a significant role in the context of bone metastasis.

AIM OF THE STUDY

Although Wenshen Zhuanggu (WSZG) formula efficiently decreased the risk of bone metastases in tumor-bearing mice, it remains unclear how WSZG formula regulates the interaction of cancer cells with osteoclasts and osteoblasts in bone metastasis of breast cancer.

MATERIALS AND METHODS

In this study, we investigated the role of WSZG formula in the progress of bone metastasis in breast cancer and focused on the cell-cell interactions of tumor cells with osteoclasts and osteoblasts. Western blotting and quantitative real-time PCR were utilized to evaluate the inhibitory activities of WSZG formula on Jagged1 expression both in vivo and in vitro. Osteoblast co-culture and osteoclastogenesis co-culture were applied to analyze the effects of WSZG formula on the interaction of tumor cells with osteoclasts and osteoblasts. A breast cancer xenograft model was also used to test the inhibitory effects of WSZG formula on bone metastasis in breast cancer.

RESULTS

WSZG formula decreased Jagged1 expression in osteolytic lesions in the breast cancer xenograft model. Additionally, WSZG formula decreased Jagged1 expression in tumor cell culture alone or co-culture with pre-osteoclasts and osteoblasts. In addition, WSZG formula decreased Jagged1 expression in Jagged1-overexpressing tumor cells.

CONCLUSION

The results of this study suggest that WSZG formula mitigates breast cancer bone metastasis through the Jagged1/Notch signaling pathway mediated by TGF-β and IL-6.

Naturally occurring compounds as pancreatic cancer therapeutics

Naturally occurring small molecule compounds have long been in the spotlight of pancreatic cancer research as potential therapeutics to prevent cancer progression and sensitize chemoresistant tumors. The hope is that terminal pancreatic cancer patients receiving aggressive chemotherapy can benefit from an increase in treatment efficacy without adding further toxicity by way of utilizing natural compounds. While preclinical studies on a number of natural compounds, such as resveratrol, curcumin, rapalogs and cannabinoids, show promising preclinical results, little has translated into clinical practice, though a number of other compounds hold clinical potential. Nevertheless, recent advances in compound formulation may increase the clinical utility of these compounds.