Curcumin inhibits TGF-β1-induced MMP-9 and invasion through ERK and Smad signaling in breast cancer MDA- MB-231 cells

Role of transforming growth factor-β in peripheral nerve regeneration

Injuries caused by trauma and neurodegenerative diseases can damage the peripheral nervous system and cause functional deficits. Unlike in the central nervous system, damaged axons in peripheral nerves can be induced to regenerate in response to intrinsic cues after reprogramming or in a growth-promoting microenvironment created by Schwann cells. However, axon regeneration and repair do not automatically result in the restoration of function, which is the ultimate therapeutic goal but also a major clinical challenge. Transforming growth factor (TGF) is a multifunctional cytokine that regulates various biological processes including tissue repair, embryo development, and cell growth and differentiation. There is accumulating evidence that TGF-β family proteins participate in peripheral nerve repair through various factors and signaling pathways by regulating the growth and transformation of Schwann cells; recruiting specific immune cells; controlling the permeability of the blood-nerve barrier, thereby stimulating axon growth; and inhibiting remyelination of regenerated axons. TGF-β has been applied to the treatment of peripheral nerve injury in animal models. In this context, we review the functions of TGF-β in peripheral nerve regeneration and potential clinical applications.

Curcumin for Treating Breast Cancer: A Review of Molecular Mechanisms, Combinations with Anticancer Drugs, and Nanosystems

Breast cancer (BC) has become the fifth most prevalent cause of cancer-related morbidity, attracting significant attention from researchers due to its heightened malignancy and drug resistance. Conventional chemotherapy approaches have proven inadequate in addressing all BC subtypes, highlighting the urgent need for novel therapeutic approaches or drugs. Curcumin (CUR), a phytochemical derived from Curcuma longa (turmeric), has shown substantial potential in inhibiting BC cell migration, metastasis, and proliferation. However, the use of CUR in this context comes with challenges due to its dynamic and easily degradable nature, poor aqueous solubility, low bioavailability, rapid metabolism, and swift systemic elimination, collectively limiting its clinical applications. As such, we provide an overview of the properties, synthesis, and characterization of the hybridization of CUR and its analogue with chemo-drug building blocks. We reviewed research from the last five years on CUR's biogenesis with respect to the regulation of BC, revealing that CUR participates in arresting BC cells in the cell cycle and significantly induces apoptosis in BC cells. Information on the chemotherapeutic and antitumor mechanisms of CUR in BC, including regulation of the cell cycle, increased cell apoptosis, and inhibition of multidrug resistance (MDR), was compiled. Additionally, we provide an overview of CUR loaded into nanomaterials that are cotreated with other chemotherapeutic drugs, such as paclitaxel, thymoquinone, and tamoxifen. In this review, we discuss different types of nanoparticles that can be used for CUR delivery, such as polymeric nanoparticles, carbon nanotubes, and liposomes. By comparing the size, entrapment efficiency, drug-loading capacity, release time, biocompatibility, pharmaceutical scale, and reproducibility of various nanomaterials, we aimed to determine which formulations are better suited for loading CUR or its analogue. Ultimately, this review is expected to offer inspiring ideas, promising strategies, and potential pathways for developing advanced anti-BC strategy nanosystems in clinical practice.

Gemini curcumin inhibits 4T1 cancer cell proliferation and modulates the expression of apoptotic and metastatic genes in Balb/c mice model

BACKGROUND

Despite the attractive anti-cancer effects, poor solubility and low bioavailability have restricted the clinical application of Curcumin. Recent findings show that Gemini nano-curcumin (Gemini-Cur) significantly improves the cellular uptake of Curcumin and its anti-cancer effect in tumor cells. Here, we aimed to assess the suppressive effect of Gemini-Cur on 4T1 breast cancer cells in vitro and, subsequently, in BALB/c mouse models.

MATERIALS AND METHODS

Fluorescence microscopy was employed to visualize cellular uptake and morphological changes of 4T1 cells during treatment with Gemini-Cur and void curcumin. MTT and annexin V/FITC assays were performed to study the toxic effect of Gemini-Cur on mouse cancer cells. For in vivo studies, BALB/c tumor-bearing mice were used to evaluate the inhibitory effect of Gemini-Cur in comparison with mice receiving free Curcumin and nanoparticles.

RESULTS

Our data showed that Gemini-Cur enters the cells and inhibits proliferation in a time- and dose-dependent manner. Annexin V/FITC confirmed apoptotic effect on 4T1 cells. In vivo studies also illustrated that tumor growth is suppressed in Gemini-Cur treated mice rather than controls. Expression studies demonstrated the modulation of apoptotic and metastatic genes, including Bax, Bcl-2, MMP-9, VEGF, and COX-2 in treated mice.

CONCLUSION

In conclusion, these data demonstrate the promising anti-cancer properties of Gemini-Cur on mice models. However, further studies at molecular and cellular levels are required to conclude this therapeutic advantage.

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.

Combined Curcumin and Luteolin Synergistically Inhibit Colon Cancer Associated with Notch1 and TGF-β Signaling Pathways in Cultured Cells and Xenograft Mice

This study aimed to select a combination of curcumin and luteolin, two phytochemicals from food, at lower concentrations with a higher inhibitory effect on colon cancer growth and investigate possible molecular mechanisms of this anti-colon cancer effect. By pairwise combination screening, we identified that the combination of curcumin (CUR) at 15 μM and luteolin (LUT) at 30 μM (C15L30) synergistically suppressed the proliferation of human colon cancer CL-188 cells, but the individual chemicals had a little inhibitory effect at the selected concentrations. This result was also confirmed in other colon cancer DLD-1cells, suggesting that this synergistic inhibitory effect of C15L30 applies to different colon cancer cells. The combination C15L30 synergistically suppressed the wound closure (wound healing assay) in CL-188 cells. We also found that the combination of CUR and LUT (at 20 mg/kg/day and 10 mg/kg/day, respectively, IP injection, 5 days for 2 weeks) synergistically suppressed tumor growth in CL-188 cell-derived xenograft mice. Western blot results showed that protein levels of Notch1 and TGF-β were synergistically reduced by the combination, both in CL-188 cells and xenograft tumors. Tumor pathological analysis revealed that combined CUR and LUT synergistically increased necrosis, but the individual treatment with CUR and LUT had no significant effect on tumor necrosis. Therefore, combined curcumin and luteolin synergically inhibit colon cancer development by suppressing cell proliferation, necrosis, and migration associated with Notch1 and TGF-β pathways. This study provides evidence that colon cancer may be prevented/treated by consuming foods having high levels of luteolin and curcumin in humans.

Natural plant extracts mediated expression regulation of TGF-β receptors and SMAD genes in human cancer cell lines

BACKGROUND

Transforming growth factor beta (TGF-β) superfamily has key role in cell proliferation which leads to tumor promoting activities at metastatic stage of cancer. Inhibition of transforming growth factor beta receptor (TGFβR) signaling pathway can provide better therapeutic strategy to control cancer. Natural products are best known for their safety, less toxic nature, antioxidant characteristics making them a promising candidate to inhibit TGFβR signaling pathway.

METHODS AND RESULTS

Crude methanolic extracts (CMEs) of 16 selected plants were prepared by using maceration method and subjected to phytochemical assays for identification of major phytometabolites particularly cancer chemopreventive antioxidant constituents. Total flavonoid content of all plants CME was > 0.6 mg/ml exhibiting the Cichorium intybus contains comparatively highest amount of total flavonoid content (0.53 mg/ml). Scanvenging activity of all plants was determined having IC₅₀ ranges between 2 and 88 (µg/ml) while Moringa oleifera revealed the maximum scavenging activity (IC₅₀ 2.03 µg/ml). Comparative cytotoxicity of plant extracts was evaluated in HUH and MCF-7 cell lines using 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) colorimetric assay. The nine active plant extracts i.e. Fagonia cretica, Argemone Mexicana, Rubus fruticosus, M. oleifera, Punica granatum, Cichorium intybus, Xanthium strumarium, Carissa opaca, Cyperus rotundus were identified based on their high antiproliferative activity > 50% against cancer cell lines and subjected to relative expression studies. Modulation of TGFβ signaling molecules (i.e.TGFβR1, 2 & 3, SMAD3, SMAD5) and ubiquitous proteins i.e. SMURF1 and SMURF2 genetic expression by potent extracts was determined by RT-PCR using GAPDH (housekeeping gene) as gene of reference.

CONCLUSIONS

This present study revealed that CME of Fagonia cretica and Argemone mexicana significantly inhibit TGF beta mediated signaling cascade by downregulating the gene expression fold change > 1 of TGFβR 1, 2 & 3 and receptor associated complex protein SMAD3 as compared to control.

Curcumin as an Enhancer of Therapeutic Efficiency of Chemotherapy Drugs in Breast Cancer

Female breast cancer is the world’s most prevalent cancer in 2020. Chemotherapy still remains a backbone in breast cancer therapy and is crucial in advanced and metastatic breast cancer treatment. The clinical efficiency of chemotherapy regimens is limited due to tumor heterogeneity, chemoresistance, and side effects. Chemotherapeutic drug combinations with natural products hold great promise for enhancing their anticancer efficacy. Curcumin is an ideal chemopreventive and chemotherapy agent owning to its multitargeting function on various regulatory molecules, key signaling pathways, and pharmacological safety. This review aimed to elucidate the potential role of curcumin in enhancing the efficacy of doxorubicin, paclitaxel, 5-fluorouracil, and cisplatin via combinational therapy. Additionally, the molecular mechanisms underlying the chemosensitizing activity of these combinations have been addressed. Overall, based on the promising therapeutic potential of curcumin in combination with conventional chemotherapy drugs, curcumin is of considerable value to develop as an adjunct for combination chemotherapy with current drugs to treat breast cancer. Furthermore, this topic may provide the frameworks for the future research direction of curcumin–chemotherapy combination studies and may benefit in the development of a novel therapeutic strategy to maximize the clinical efficacy of anticancer drugs while minimizing their side effects in the future breast cancer treatment.

Infection by High-Risk Human Papillomaviruses, Epithelial-to-Mesenchymal Transition and Squamous Pre-Malignant or Malignant Lesions of the Uterine Cervix: A Series of Chained Events?

Wound healing requires static epithelial cells to gradually assume a mobile phenotype through a multi-step process termed epithelial-to-mesenchymal transition (EMT). Although it is inherently transient and reversible, EMT perdures and is abnormally activated when the epithelium is chronically exposed to pathogens: this event deeply alters the tissue and eventually contributes to the development of diseases. Among the many of them is uterine cervical squamous cell carcinoma (SCC), the most frequent malignancy of the female genital system. SCC, whose onset is associated with the persistent infection of the uterine cervix by high-risk human papillomaviruses (HR-HPVs), often relapses and/or metastasizes, being resistant to conventional chemo- or radiotherapy. Given that these fearsome clinical features may stem, at least in part, from the exacerbated and long-lasting EMT occurring in the HPV-infected cervix; here we have reviewed published studies concerning the impact that HPV oncoproteins, cellular tumor suppressors, regulators of gene expression, inflammatory cytokines or growth factors, and the interactions among these effectors have on EMT induction and cervical carcinogenesis. It is predictable and desirable that a broader comprehension of the role that EMT inducers play in SCC pathogenesis will provide indications to flourish new strategies directed against this aggressive tumor.

Circulating Tumour Cells (CTCs) in NSCLC: From Prognosis to Therapy Design

Designing optimal (neo)adjuvant therapy is a crucial aspect of the treatment of non-small-cell lung carcinoma (NSCLC). Standard methods of chemotherapy, radiotherapy, and immunotherapy represent effective strategies for treatment. However, in some cases with high metastatic activity and high levels of circulating tumour cells (CTCs), the efficacy of standard treatment methods is insufficient and results in treatment failure and reduced patient survival. CTCs are seen not only as an isolated phenomenon but also a key inherent part of the formation of metastasis and a key factor in cancer death. This review discusses the impact of NSCLC therapy strategies based on a meta-analysis of clinical studies. In addition, possible therapeutic strategies for repression when standard methods fail, such as the administration of low-toxicity natural anticancer agents targeting these phenomena (curcumin and flavonoids), are also discussed. These strategies are presented in the context of key mechanisms of tumour biology with a strong influence on CTC spread and metastasis (mechanisms related to tumour-associated and -infiltrating cells, epithelial–mesenchymal transition, and migration of cancer cells).

Suppression of latent transforming growth factor-β (TGF-β)-binding protein 1 (LTBP1) inhibits natural killer/ T cell lymphoma progression by inactivating the TGF-β/Smad and p38MAPK pathways

BACKGROUND

Natural killer/T cell lymphoma (NKTCL) is a distinct subtype of Non-Hodgkin's lymphoma with highly aggressive clinical behavior. We aim to investigate the function of Latent transforming growth factor β binding protein 1 (LTBP1) and transforming growth factor beta1 (TGF-β1) and complex molecular pathogenesis of this disease.

METHODS

NKTCL patients and reactive lymph nodes patients were recruited in this study. The expression of LTBP1 and TGF-β1 was examined using qRT-PCR, Western blot, IHC and ELISA analyses in biopsied tissues and serum from participants and NKTCL cell lines. Cell proliferation was determined using CFSE. Cell cycle and apoptosis were evaluated using flow cytometric analyses. The expression of Ki-67, CDK4 and cyclinD1 proteins was measured using Western blot analyses. The roles of LTBP-1/TGF-β1 in EMT program were determined by measuring E-cadherin, N-cadherin and Vimentin using Western blot analyses. The effects of LTBP-1 and TGF-β1 on tumor progression in vivo were determined by animal experiments.

RESULTS

LTBP-1 and TGF-β1 levels were elevated in NKTCL tissues and serum. The expression of LTBP-1 was positively correlated with the expression of TGF-β1 in NKTCL tissues. LTBP-1 was overexpressed in NKTCL cells. Knockdown of LTBP-1 suppressed cell proliferation and cell cycle progression, induced cell apoptosis, and suppressed EMT program in NKTCL cells. These effects of LTBP-1 knockdown were attenuated after TGF-β1 stimulation. Knockdown of LTBP-1 inhibited NKTCL tumor weight and volume in vivo. Also, stimulation of TGF-β1 attenuated the suppressive effects on tumor growth from sh-LTBP-1. Silencing of LTBP-1 lowered cellular TGF-β1, phosphorylated-Smad2, phosphorlyatd-Smad3, and phosphorylated-p38 and the suppressive effects were reversed after stimulation of TGF-β1.

CONCLUSION

Our findings suggested that inhibition of LTBP-1/TGF-β1 suppressed the malignant phenotypes of NKTCL cells and tumor growth via inactivating the canonical TGF-β/Smad signaling and p38^MAPK signaling.

Curcumin: Modulator of Key Molecular Signaling Pathways in Hormone-Independent Breast Cancer

Simple Summary

Breast cancer remains the most commonly diagnosed cancer and the leading cause of cancer death among females worldwide. It is a highly heterogeneous disease, classified according to hormone and growth factor receptor expression. Patients with triple negative breast cancer (TNBC) (estrogen receptor-negative/progesterone receptor-negative/human epidermal growth factor receptor (HER2)-negative) and hormone-independent HER2 overexpressing subtypes still represent highly aggressive behavior, metastasis, poor prognosis, and drug resistance. Thus, new alternative anticancer agents based on the use of natural products have been receiving enormous attention. In this regard, curcumin is a promising lead in cancer drug discovery due its ability to modulate a diverse range of molecular targets and signaling pathways. The current review has emphasized the underlying mechanism of curcumin anticancer action mediated through the modulation of PI3K/Akt/mTOR, JAK/STAT, MAPK, NF-ĸB, p53, Wnt/β-catenin, apoptosis, and cell cycle pathways in hormone-independent breast cancer, providing frameworks for future studies and insights to improve its efficiency in clinical practice.

Abstract

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among women worldwide. Despite the overall successes in breast cancer therapy, hormone-independent HER2 negative breast cancer, also known as triple negative breast cancer (TNBC), lacking estrogens and progesterone receptors and with an excessive expression of human epidermal growth factor receptor 2 (HER2), along with the hormone-independent HER2 positive subtype, still remain major challenges in breast cancer treatment. Due to their poor prognoses, aggressive phenotype, and highly metastasis features, new alternative therapies have become an urgent clinical need. One of the most noteworthy phytochemicals, curcumin, has attracted enormous attention as a promising drug candidate in breast cancer prevention and treatment due to its multi-targeting effect. Curcumin interrupts major stages of tumorigenesis including cell proliferation, survival, angiogenesis, and metastasis in hormone-independent breast cancer through the modulation of multiple signaling pathways. The current review has highlighted the anticancer activity of curcumin in hormone-independent breast cancer via focusing on its impact on key signaling pathways including the PI3K/Akt/mTOR pathway, JAK/STAT pathway, MAPK pathway, NF-ĸB pathway, p53 pathway, and Wnt/β-catenin, as well as apoptotic and cell cycle pathways. Besides, its therapeutic implications in clinical trials are here presented.

Curcumin and cancer biology: Focusing regulatory effects in different signalling pathways

Cancer is the second-leading cause of death worldwide. Till date, many such effective treatments are available, for example chemotherapy, surgery, and radiation therapy, but there are severe associated side effects, such as increased infection risk, constipation, hair loss, anaemia, among others. Thus, the need for effective therapeutic strategies and screening methodology arises. Researchers around the world are increasingly trying to discover anticancer therapies with as few side effects as possible and many are now focusing on phytochemicals, like curcumin. Curcumin is a bright yellow substance isolated from the plant rhizomes of Curcuma longa L. To this molecule a high therapeutic benefit has been underlined, being able to alter the development of cancer by different mechanisms, such as regulating multiple microRNA expression, modifying a series of signalling pathways, that is, Akt, Bcl-2, PTEN, p53, Notch, and Erbb. Another major pathway that curcumin targets is the matrix metalloproteinase (MMP) gene expression. In fact, MMPs are responsible for the degradation of the cell-extracellular matrix, which can lead to the diseased condition and many different pathways contribute to its activity, such as JAK/STAT, NF-κB, MAPK/ERK, COX-2, ROS, TGF-β, among others. In this review, we have attempted to describe the curcumin regulatory effect on different cell signalling pathways involved in the progression of different types of cancers.

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.

Therapeutic potential of pharmacological TGF-β signaling pathway inhibitors in the pathogenesis of breast cancer

The TGF-β signaling pathway plays an important role in cancer cell proliferation, growth, inflammation, angiogenesis, and metastasis. The role of TGF-β signaling in the pathogenesis of breast cancer is complex. TGF-β acts as a tumor suppressor in the early stages of disease, and as a tumor promoter in its later stages. Over-activation of the TGF-β signaling pathway and over-expression of the TGF-β receptors are frequently found in breast tumors. Suppression of TGF-β pathway using biological or pharmacological inhibitors is a potentially novel therapeutic approach for breast cancer treatment. This review summarizes the regulatory role of TGF-β signaling in the pathogenesis of breast cancer for a better understanding and hence a better management of this disease.

Curcumin-loaded PLA-PEG copolymer nanoparticles for treatment of liver inflammation in streptozotocin-induced diabetic rats

This report focused on loading curcumin (CUR) drug into biodegradable Polylactide-poly(ethylene glycol) (PLA-PEG) copolymer nanoparticles as an effective anti-inflammatory agent in vivo to overcome the limitations resulted from the free CUR. By a simple nano-emulsification technique, hydrophobic CUR was loaded into hydrophobic polymer's segments and stabilized by cationic surfactant. They were then characterized by DLS, TEM, and SEM techniques providing monodispersed and spherical nanoparticles with an average diameter of 117 nm and high surface charge of +35 mV. Thereafter, they were orally administrated into five groups of rats, typically, control (healthy rats), streptozotocin (STZ)-induced diabetic rats, diabetics treated with free CUR, diabetics treated with PLA-PEG NPs, and diabetics treated with CUR-encapsulated PLA-PEG NPs. Next, complete blood analyses were assessed including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and nuclear factor kappa B (NF-ҡB), reduced glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO), cyclooxygenase (COX-2), Peroxisome proliferator-activated receptors (PPAR-γ) and transforming growth factor-β1 (TGF-β1). The obtained results demonstrated that diabetes initially produced liver inflammation in rats manifested by leveraging the mean levels of serum AST, ALT inducing oxidative stress resulting in a clear increase in the levels of hepatic MDA and NO concomitant with a remarkable decrease in GSH. Moreover, diabetes significantly increased serum NF-ҡB, hepatic COX-2 and TGF-β1, while highly reduced hepatic PPAR-γ. In contrast, both CUR free and CUR-encapsulated NPs ameliorated the negative changes in diabetes but CUR-encapsulated NPs showed more pronounced treated effect than free CUR. In addition, histopathological investigations were performed on the liver tissues of all groups, showing a mitigation in inflammation while treating with CUR-NPs.

Mechanistic evaluation of phytochemicals in breast cancer remedy: current understanding and future perspectives

Breast cancer is one of the most commonly diagnosed cancers around the globe and accounts for a large proportion of fatalities in women. Despite the advancement in therapeutic and diagnostic procedures, breast cancer still represents a major challenge. Current anti-breast cancer approaches include surgical removal, radiotherapy, hormonal therapy and the use of various chemotherapeutic drugs. However, drug resistance, associated serious adverse effects, metastasis and recurrence complications still need to be resolved which demand safe and alternative strategies. In this scenario, phytochemicals have recently gained huge attention due to their safety profile and cost-effectiveness. These phytochemicals modulate various genes, gene products and signalling pathways, thereby inhibiting breast cancer cell proliferation, invasion, angiogenesis and metastasis and inducing apoptosis. Moreover, they also target breast cancer stem cells and overcome drug resistance problems in breast carcinomas. Phytochemicals as adjuvants with chemotherapeutic drugs have greatly enhanced their therapeutic efficacy. This review focuses on the recently recognized molecular mechanisms underlying breast cancer chemoprevention with the use of phytochemicals such as curcumin, resveratrol, silibinin, genistein, epigallocatechin gallate, secoisolariciresinol, thymoquinone, kaempferol, quercetin, parthenolide, sulforaphane, ginsenosides, naringenin, isoliquiritigenin, luteolin, benzyl isothiocyanate, α-mangostin, 3,3'-diindolylmethane, pterostilbene, vinca alkaloids and apigenin.

Molecular Mechanisms Underlying Curcumin-Mediated Therapeutic Effects in Type 2 Diabetes and Cancer

The growing prevalence of age-related diseases, especially type 2 diabetes mellitus (T2DM) and cancer, has become global health and economic problems. Due to multifactorial nature of both diseases, their pathophysiology is not completely understood so far. Compelling evidence indicates that increased oxidative stress, resulting from an imbalance between production of reactive oxygen species (ROS) and their clearance by antioxidant defense mechanisms, as well as the proinflammatory state contributes to the development and progression of the diseases. Curcumin (CUR; diferuloylmethane), a well-known polyphenol derived from the rhizomes of turmeric Curcuma longa, has attracted a great deal of attention as a natural compound with beneficial antidiabetic and anticancer properties, partly due to its antioxidative and anti-inflammatory actions. Although this polyphenolic compound is increasingly being recognized for its growing number of protective health effects, the precise molecular mechanisms through which it reduces diabetes- and cancer-related pathological events have not been fully unraveled. Hence, CUR is the subject of intensive research in the fields Diabetology and Oncology as a potential candidate in the treatment of both T2DM and cancer, particularly since current therapeutic options for their treatment are not satisfactory in clinics. In this review, we summarize the recent progress made on the molecular targets and pathways involved in antidiabetic and anticancer activities of CUR that are responsible for its beneficial health effects.

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

Curcumin, a bioactive and pharmacologically efficient component isolated from Curcuma longa has attracted considerable attention because of its ability to modulate diverse cellular and physiological pathways. WNT, TGF/SMAD, NOTCH, and SHH are fundamentally different signaling cascades, but their choreographed activation is strongly associated with cancer development and progression. In this review we have attempted to set spotlight on regulation of different cell signaling pathways by curcumin in different cancers. We partition this multi-component review into in-depth biological understanding of various signal transduction cascades and how curcumin targets intracellular signal transducers of deregulated pathways to inhibit cancer development and progression. Rapidly broadening landscape of both established and candidate oncogenic driver mutations identified in different cancers is a major stumbling block in the standardization of drugs having significant clinical outcome. Intra and inter-tumor heterogeneity had leveraged the complexity of therapeutic challenges to another level. Multi-pronged approach and molecularly guided treatments will be helpful in improving the clinical outcome.

Effect of Curcuma xanthorrhiza Supplementation on Systemic Lupus Erythematosus Patients with Hypovitamin D Which Were Given Vitamin D3 towards Disease Activity (SLEDAI), IL-6, and TGF-β1 Serum

Background

Curcumin contained in Curcuma xanthorrhiza is an immunomodulator that has similar biological effect as vitamin D. Combination of curcumin and vitamin D₃ is expected to work synergistically.

Objective

To determine the effect of Curcuma xanthorrhiza supplementation on vitamin D₃ administration to SLEDAI, IL-6, and TGF-β1 serum in SLE patients with hypovitamin D.

Methods

This was a double-blind RCT conducted in Saiful Anwar Hospital, Malang, in January 2016–March 2017. Subjects were SLE active (SLEDAI > 3) with levels of 25(OH)D3 ≤ 30 ng/ml and divided into two groups: those receiving cholecalciferol 3 × 400 IU and placebo 3 × 1 tablets (group I) and those receiving 3 × 400 IU cholecalciferol and Curcuma xanthorrhiza 3 × 20 mg for 3 months (group II). SLEDAI, levels of vitamin D, IL-6, and TGF-β1 in serum were evaluated before and after the treatment.

Results

There were no significant differences in SLEDAI reduction, decreased serum levels of IL-6, and increased levels of TGF-β1 serum among groups after the treatment. Decreased levels of serum IL-6 have a positive correlation with SLEDAI reduction. Conclusion. Curcuma xanthorrhiza supplementation on vitamin D₃ had no effects on SLEDAI and serum levels of IL-6 and TGF-β1. This clinical trial is registered with NCT03155477.

Salvia miltiorrhiza extract inhibits TPA-induced MMP-9 expression and invasion through the MAPK/AP-1 signaling pathway in human breast cancer MCF-7 cells

Cancer cell invasion is crucial for metastasis. A major factor in the capacity of cancer cell invasion is the activation of matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix. Salvia miltiorrhiza has been used as a promotion for blood circulation to remove blood stasis. Numerous previous studies have demonstrated that S. miltiorrhiza extracts (SME) decrease lipid levels and inhibit inflammation. However, the mechanism behind the effect of SME on breast cancer invasion has not been identified. The inhibitory effects of SME on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP-9 expression were assessed using western blotting, reverse transcription-quantitative polymerase chain reaction and zymography assays. MMP-9 upstream signal proteins, including mitogen-activated protein kinases and activator protein 1 (AP-1) were also investigated. Cell invasion was assessed using a matrigel invasion assay. The present study demonstrated the inhibitory effects of the SME ethanol solution on MMP-9 expression and cell invasion in TPA-treated MCF-7 breast cancer cells. SME suppressed TPA-induced MMP-9 expression and MCF-7 cell invasion by blocking the transcriptional activation of AP-1. SME may possess therapeutic potential for inhibiting breast cancer cell invasiveness.

Therapeutic potential of novel formulated forms of curcumin in the treatment of breast cancer by the targeting of cellular and physiological dysregulated pathways

Breast cancer is among the most important causes of cancer related death in women. There is a need for novel agents for targeting key signaling pathways to either improve the efficacy of the current therapy, or reduce toxicity. There is some evidence that curcumin may have antitumor activity in breast cancer. Several clinical trials have investigated its activity in patients with breast cancer, including a recent trial in breast cancer patients receiving radiotherapy, in whom it was shown that curcumin reduced the severity of radiation dermatitis, although it is associated with low bioavailability. Several approaches have been developed to increase its absorption rate (e.g., nano crystals, liposomes, polymers, and micelles) and co-delivery of curcumin with adjuvants as well as different conjugation to enhance its bioavailability. In particular, micro-emulsions is an option for transdermal curcumin delivery, which has been reported to increase its absorption. Lipid-based nano-micelles is another approach to enhance curcumin absorption via gastrointestinal tract, while polymer-based nano-formulations (e.g., poly D, L-lactic-co-glycolic [PLGA]) allows the release of curcumin at a sustained level. This review summarizes the current data of the therapeutic potential of novel formulations of curcumin with particular emphasis on recent preclinical and clinical studies in the treatment of breast cancer.

Curcumin induces apoptosis and suppresses invasion through MAPK and MMP signaling in human monocytic leukemia SHI-1 cells

CONTEXT

Curcumin is a polyphenolic compound extracted from rhizomes of the tropical plant Curcuma longa L. (Zingiberaceae) and it has antitumor, antioxidative, and anti-inflammatory effects. However, its effects on leukemia cell proliferation and invasion are not clear.

OBJECTIVE

This study investigates the effects of curcumin on acute monocytic leukemia SHI-1 cells at the molecular level.

MATERIALS AND METHODS

The effects of SHI-1 cells treated with 6.25-25 μM curcumin for 12-48 h were measured by MTT assay, flow cytometry, and Matrigel transwell assay; the underlying molecular mechanisms were assessed by quantitative PCR, Western blotting, and gelatin zymography.

RESULTS

Treatment of SHI-1 cells with curcumin inhibited cell proliferation in a dose- and time-dependent manner, and the IC50 values at 12, 24, and 48 h were 32.40, 14.13, and 9.67 μM. Curcumin inhibited SHI-1 cell proliferation by arresting the cells in the S-phase, increasing the number of Annexin V-FITC(+)/PI(-) cells and promoting the loss of △Ψm. The results of PCR and Western blotting showed that curcumin increased the FasL mRNA level; inhibited Bcl-2, NF-κB, and ERK expression; and activated P38 MAPK, JNK, and caspase-3. Additionally, curcumin partially suppressed SHI-1 cell invasion and attenuated the mRNA transcription and secretion of MMP-2 and MMP-9.

DISCUSSION AND CONCLUSION

This study demonstrates that curcumin not only induces SHI-1 cell apoptosis, possibly via both intrinsic and extrinsic pathways triggered by JNK, P38 MAPK and ERK signaling, but also partially suppresses SHI-1 cell invasion, likely by reducing the levels of transcription and secretion of MMP-2 and MMP-9.

Phosphorylated-p38 mitogen-activated protein kinase expression is associated with clinical factors in invasive breast cancer

Purpose

P38 mitogen-activated protein kinases (MAPK) level is an important prognostic factor in breast cancer. This study was performed to detect the expressions of P-p38 MAPK expression in breast cancer and explore their correlations with clinicopathological factors.

Experimental design

Tumor samples from 355 Chinese patients diagnosed with invasive breast cancer and adjacent non-cancerous tissue were collected between 2003 and 2010. The expression of P-p38 MAPK was analyzed using immunohistochemical staining. The correlations between P-p38 MAPK expression and clinicopathological findings including age, AJCC Stage, Histologic characters, ER, PR, and HER2 were analyzed using the parametric correlation method. P-p38 MAPK was selected as dependent variable to perform multivariate analysis respectively at last.

Results

Overall, 161 (45 %) and 183 (52 %) of the 355 specimens showed positive P-p38 MAPK staining in the cytoplasm and nucleus respectively, which were significant higher than that in the adjacent non-cancerous tissues in both the cytoplasm and the nucleus. High P-p38 MAPK expression of cytoplasm and nucleus were both associated with positive PR status in luminal A/B type of breast cancer, and were both associated with positive HER2 status in HER2-positive type of breast cancer. The result of multivariate analysis demonstrated that HER2 and PR were both significantly association with P-p38 MAPK expression of cytoplasm and nucleus.

Conclusions

Our study suggests that P-p38 MAPK expression were significantly associated with clinicopathological factors and PR/HER2 might association with phosphorylation of p38 MAPK in different types of breast cancer.

Inhibition of Transforming Growth Factor-β (TGF-β) Signaling by Scutellaria baicalensis and Fritillaria cirrhosa Extracts in Endometrial Cancer

Transforming growth factor-β (TGF-β), regulates cell proliferation, angiogenesis, metastasis, and is an inducer of epithelial-mesenchymal transition (EMT). Cancer cells exhibit activated TGF-β/SMAD signaling pathway and its inhibition is an attractive strategy for cancer treatment. The Chinese Herbs Scutellaria baicalensis (SB) and Fritillaria cirrhosa (FC) have been shown to be beneficial to cancer patients, but the mechanisms by which the extracts of two herbs elicit the beneficial effects are unclear. In this study, we have used human endometrial cancer cells to assess the anticancer efficacy of SB and FC on TGF-β signaling pathway components. SB and FC treatment of cancer cells resulted in a significant decrease in expression of TGF-β isoforms, TGF-β receptors, and SMADs. Both herbs effectively inhibited basal and TGF-β1-induced cancer cell proliferation and invasion, which was accompanied with abrogation of Snail, Slug, matrix metalloproteinases (MMPs), αvβ3 integrin, focal adhesion kinase (FAK), and p-FAK expression. An inhibitor of TGF-βRI blocked TGF-β1-induced cell invasion and significantly diminished antitumor effects of SB and FC. These results suggest that SB and FC block endometrial cancer growth by downregulating TGF-β/SMAD signaling pathway.

Suppression of TPA-induced cancer cell invasion by Peucedanum japonicum Thunb. extract through the inhibition of PKCα/NF-κB-dependent MMP-9 expression in MCF-7 cells

Metastatic cancers spread from their site of origin (the primary site) to other parts of the body. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix, is important in metastatic cancers as it plays a major role in cancer cell invasion. The present study examined the inhibitory effect of an ethanol extract of Peucedanum japonicum Thunb. (PJT) on MMP-9 expression and the invasion of MCF-7 breast cancer cells induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Western blot analysis, gelatin zymography, and reverse transcription-quantitative PCR revealed that PJT significantly suppressed MMP-9 expression and activation in a dose-dependent manner. Furthermore, PJT attenuated TPA-induced nuclear translocation and the transcriptional activation of nuclear factor (NF)-κB. The results indicated that the PJT-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involved the suppression of the PKCα/NF-κB pathway in MCF-7 cells. Thus, the inhibition of MMP-9 expression by PJT may have potential value as a therapy for restricting the invasiveness of breast cancer.

Recent Advances of Curcumin and its Analogues in Breast Cancer Prevention and Treatment

More than 230,000 diagnosed cases of invasive breast cancer in women was estimated in 2014 and an expected 40,000 deaths attributed to the aggressive carcinoma. An effective approach to diminish the morbidity and mortality of breast cancer is the development of chemopreventive and chemotherapeutic agents. Nutraceuticals have demonstrated their ability to proficiently halt carcinogenesis. The administration of natural compounds able to effectively serve as chemoprevention and chemotherapeutics without causing harm or adverse effects is imperative. Curcumin derived from the rhizome of Curcuma longa L., is a common spice of India, used for centuries because of its medicinal properties. The main component of curcumin possesses a wide range of biological activities; anti-proliferative, anti-inflammatory, and apoptotic characteristics modulated through the inactivation of pathways such as EGK and Akt/mTOR. In addition, curcumin alters the expression of cytokines, transcription factors, and enzymes involved in cell vitality. The in vivo application of curcumin in breast cancer is hindered by its limited bioavailabiity. The synthesis of curcumin analogues and delivery via nanoparticles has demonstrated enhanced bioavailability of curcumin in the malignancy. This review focuses on recent developments in the use of curcumin, curcumin analogues, and novel delivery systems as a preventive and therapeutic method for breast cancer.

Curcumin suppresses migration and invasion of human endometrial carcinoma cells

Curcumin, a widely used Chinese herbal medicine, has historically been used in anti-cancer therapies. However, the anti-metastatic effect and molecular mechanism of curcumin in endometrial carcinoma (EC) are still poorly understood. The purpose of this study was to detect the anti-metastatic effects of curcumin and the associated mechanism(s) in EC. Based on assays carried out in EC cell lines, it was observed that curcumin inhibited EC cell migration and invasion in vitro. Furthermore, following treatment with curcumin for 24 h, there was a decrease in the expression levels of matrix metalloproteinase (MMP)-2 and -9 as well as proteinase activity in EC cells. Moreover, curcumin treatment significantly decreased the levels of the phosphorylated form of extracellular signal-regulated kinase (ERK) 1/2. MEK1 overexpression partially blocked the anti-metastatic effects of curcumin. Combined treatment with ERK inhibitor U0126 and curcumin resulted in a synergistic reduction in MMP-2/-9 expression; the invasive capabilities of HEC-1B cells were also inhibited. In conclusion, curcumin inhibits tumor cell migration and invasion by reducing the expression and activity of MMP-2/9 via the suppression of the ERK signaling pathway, suggesting that curcumin is a potential therapeutic agent for EC.

The beneficial role of curcumin on inflammation, diabetes and neurodegenerative disease: A recent update

The concept of using phytochemicals has ushered in a new revolution in pharmaceuticals. Naturally occurring polyphenols (like curcumin, morin, resveratrol, etc.) have gained importance because of their minimal side effects, low cost and abundance. Curcumin (diferuloylmethane) is a component of turmeric isolated from the rhizome of Curcuma longa. Research for more than two decades has revealed the pleiotropic nature of the biological effects of this molecule. More than 7000 published articles have shed light on the various aspects of curcumin including its antioxidant, hypoglycemic, anti-inflammatory and anti-cancer activities. Apart from these well-known activities, this natural polyphenolic compound also exerts its beneficial effects by modulating different signalling molecules including transcription factors, chemokines, cytokines, tumour suppressor genes, adhesion molecules, microRNAs, etc. Oxidative stress and inflammation play a pivotal role in various diseases like diabetes, cancer, arthritis, Alzheimer's disease and cardiovascular diseases. Curcumin, therefore, could be a therapeutic option for the treatment of these diseases, provided limitations in its oral bioavailability can be overcome. The current review provides an updated overview of the metabolism and mechanism of action of curcumin in various organ pathophysiologies. The review also discusses the potential for multifunctional therapeutic application of curcumin and its recent progress in clinical biology.

Curcumin analogue A501 induces G2/M arrest and apoptosis in non-small cell lung cancer cells

Curcumin and its analogues have been reported to exert anti-cancer activity against a variety of tumors. Here, we reported A501, a new curcumin analogue. The effect of A501 on cell viability was detected by MTT assay, the result showed that A501 had a better inhibiting effect on the four non-small cell lung cancer (NSCLC) cells than that of curcumin. Moreover, Colony forming experiment showed A501 significant restrained cell proliferation. Flow cytometry displayed A501 can cause G2/M arrest and induce apoptosis. Western blotting showed that A501 decreased the expression of cyclinB1, cdc-2, bcl-2, while increased the expression of p53, cleaved caspase-3 and bax. In conclusion, curcumin analogues A501 played antitumor activity by inhibiting cell proliferation and inducing apoptosis of NSCLC cells. And it was likely to be a promising starting point for the development of curcumin-based anticancer drugs.

Dissecting the role of curcumin in tumour growth and angiogenesis in mouse model of human breast cancer

Breast cancer is considered the most common cancer for women worldwide and it is now the second leading cause of cancer-related deaths among females in the world. Since breast cancer is highly resistant to chemotherapy, alternative anticancer strategies have been developed. In particular, many studies have demonstrated that curcumin, a derivative of turmeric, can be used as natural agent in treatment of some types of cancer by playing antiproliferative and antioxidant effects. In our study, we assessed the antitumor activities of curcumin in ER-negative human breast cancer cell line resistant to chemotherapy, MDA.MB231 by in vitro and in vivo experiments. In vitro data allowed us to demonstrate that curcumin played a role in regulation of proliferation and apoptosis in MDA.MB231 cells. In vivo, by generation of mouse model of breast cancer, we showed that treatment of curcumin inhibited tumor growth and angiogenesis. Specifically, we showed that curcumin is able to deregulate the expression of cyclin D1, PECAM-1, and p65, which are regulated by NF-κB. Our data demonstrated that curcumin could be used as an adjuvant agent to chemotherapy in treatment of triple negative breast cancer.

Curcumin and emodin down-regulate TGF-β signaling pathway in human cervical cancer cells

Cervical cancer is the major cause of cancer related deaths in women, especially in developing countries and Human Papilloma Virus infection in conjunction with multiple deregulated signaling pathways leads to cervical carcinogenesis. TGF-β signaling in later stages of cancer is known to induce epithelial to mesenchymal transition promoting tumor growth. Phytochemicals, curcumin and emodin, are effective as chemopreventive and chemotherapeutic compounds against several cancers including cervical cancer. The main objective of this work was to study the effect of curcumin and emodin on TGF-β signaling pathway and its functional relevance to growth, migration and invasion in two cervical cancer cell lines, SiHa and HeLa. Since TGF-β and Wnt/β-catenin signaling pathways are known to cross talk having common downstream targets, we analyzed the effect of TGF-β on β-catenin (an important player in Wnt/β-catenin signaling) and also studied whether curcumin and emodin modulate them. We observed that curcumin and emodin effectively down regulate TGF-β signaling pathway by decreasing the expression of TGF-β Receptor II, P-Smad3 and Smad4, and also counterbalance the tumorigenic effects of TGF-β by inhibiting the TGF-β-induced migration and invasion. Expression of downstream effectors of TGF-β signaling pathway, cyclinD1, p21 and Pin1, was inhibited along with the down regulation of key mesenchymal markers (Snail and Slug) upon curcumin and emodin treatment. Curcumin and emodin were also found to synergistically inhibit cell population and migration in SiHa and HeLa cells. Moreover, we found that TGF-β activates Wnt/β-catenin signaling pathway in HeLa cells, and curcumin and emodin down regulate the pathway by inhibiting β-catenin. Taken together our data provide a mechanistic basis for the use of curcumin and emodin in the treatment of cervical cancer.

Curcumin inhibits LPA-induced invasion by attenuating RhoA/ROCK/MMPs pathway in MCF7 breast cancer cells

Breast cancer generally shows poor prognosis because of its invasion and metastasis. Lysophosphatidic acid (LPA) induces and aggravates cancer invasion and metastasis by activating its downstream signal pathways. RhoA/ROCK/MMP signaling was found one of the LPA-induced pathways, which may be involved in invasion of breast cancer. Furthermore, we investigated whether this pathway was involved in curcumin's effect against LPA-induced invasion. LPA incubation was used to enhance invasion of MCF-7 breast cancer cells. RhoA expression was knocked-down by siRNA technique. MTT assay was used to evaluate the proliferation. Transwell assay was utilized to investigate the invasion ability of MCF-7 cells. Real-time PCR and Western blotting were used to assess the expressions of RhoA, ROCK1, ROCK2, MMP2 and MMP9 at both translational and transcriptional levels. The RhoA and ROCK activities were also evaluated. LPA incubation significantly boosted invasion rate of MCF-7. RhoA silencing by siRNA dramatically inhibited LPA-enhanced invasion. Concurrently, RhoA and ROCK activities and expression levels of RhoA, ROCK1, ROCK2, MMP2 and MMP9 were down-regulated by RhoA siRNA transfection. In order to avoid influence of cytotoxicity of curcumin, concentrations below 45 μmol/L were selected to further investigate the mechanism of curcumin's anti-invasion effect. Invasion of LPA-incubated MCF-7 cells was impaired by curcumin in a concentration-dependent manner. Concurrently, RhoA and ROCK activities and expression levels of RhoA, ROCK1, ROCK2, MMP2 and MMP9 were down-regulated by curcumin in a concentration-dependent manner. In conclusion, RhoA/ROCK/MMPs pathway activation is involved in LPA-induced invasion in MCF-7 cells; curcumin inhibited LPA-induced invasion in MCF-7 cells by attenuating RhoA/ROCK/MMPs pathway.

To study the effect of curcumin on the growth properties of circulating endothelial progenitor cells

Curcumin has been shown to regulate the expression of genes implicated in tumor cell proliferation, metastasis, chemotherapy resistance, and angiogenesis. Endothelial progenitor cells (EPCs) have been recently described in the peripheral blood as cells contributing to both physiological and pathological angiogenesis. In the current study, we evaluated the effect of curcumin on these angiogenic cells. EPCs were isolated, expanded, and characterized ex vivo. These cells were then treated with different concentrations of curcumin. The formation of EPC colonies in culture and their proliferation was analyzed by 5'-bromo-2'-deoxyuridine assays in absence and presence of curcumin. Further, the expression of two important cell cycle inhibitory proteins, p21 and p53, in the curcumin- and culture medium-treated cells without curcumin was evaluated by intracellular flow cytometry. The results showed that there was a significant decrease in the formation of EPC colonies in culture. EPC proliferation was significantly inhibited by curcumin in a dose-dependent manner. Flow cytometry analysis showed a twofold increase in the expression of both p21 and p53 in curcumin-treated cells as compared to the medium-treated cells, suggesting that curcumin inhibits EPC growth by mainly inhibiting the G1 to S phase transition in the cell cycle. It would be further worthwhile to study the effect of curcumin on EPC-mediated angiogenic activity.

Molecular mechanism of TGF-β signaling pathway in colon carcinogenesis and status of curcumin as chemopreventive strategy

Colon cancer is one of the third most common cancer in man, the second most common cancer in women worldwide, and the second leading cause of mortality in the USA. There are a number of molecular pathways that have been implicated in colon carcinogenesis, including TGF-β/Smad signaling pathway. TGF-β (transforming growth factor-beta) signaling pathway has the potential to regulate various biological processes including cell growth, differentiation, apoptosis, extracellular matrix modeling, and immune response. TGF-β signaling pathway acts as a tumor suppressor, but alterations in TGF-β signaling pathway promotes colon cancer cell growth, migration, invasion, angiogenesis, and metastasis. Here we review the role of TGF-β signaling cascade in colon carcinogenesis and multiple molecular targets of curcumin in colon carcinogenesis. Elucidation of the molecular mechanism of curcumin on TGF-β signaling pathway-induced colon carcinogenesis may ultimately lead to novel and more effective treatments for colon cancer.

pTyr421 cortactin is overexpressed in colon cancer and is dephosphorylated by curcumin: involvement of non-receptor type 1 protein tyrosine phosphatase (PTPN1)

Cortactin (CTTN), first identified as a major substrate of the Src tyrosine kinase, actively participates in branching F-actin assembly and in cell motility and invasion. CTTN gene is amplified and its protein is overexpressed in several types of cancer. The phosphorylated form of cortactin (pTyr⁴²¹) is required for cancer cell motility and invasion. In this study, we demonstrate that a majority of the tested primary colorectal tumor specimens show greatly enhanced expression of pTyr⁴²¹-CTTN, but no change at the mRNA level as compared to healthy subjects, thus suggesting post-translational activation rather than gene amplification in these tumors. Curcumin (diferulolylmethane), a natural compound with promising chemopreventive and chemosensitizing effects, reduced the indirect association of cortactin with the plasma membrane protein fraction in colon adenocarcinoma cells as measured by surface biotinylation, mass spectrometry, and Western blotting. Curcumin significantly decreased the pTyr⁴²¹-CTTN in HCT116 cells and SW480 cells, but was ineffective in HT-29 cells. Curcumin physically interacted with PTPN1 tyrosine phosphatases to increase its activity and lead to dephosphorylation of pTyr⁴²¹-CTTN. PTPN1 inhibition eliminated the effects of curcumin on pTyr⁴²¹-CTTN. Transduction with adenovirally-encoded CTTN increased migration of HCT116, SW480, and HT-29. Curcumin decreased migration of HCT116 and SW480 cells which highly express PTPN1, but not of HT-29 cells with significantly reduced endogenous expression of PTPN1. Curcumin significantly reduced the physical interaction of CTTN and pTyr⁴²¹-CTTN with p120 catenin (CTNND1). Collectively, these data suggest that curcumin is an activator of PTPN1 and can reduce cell motility in colon cancer via dephosphorylation of pTyr⁴²¹-CTTN which could be exploited for novel therapeutic approaches in colon cancer therapy based on tumor pTyr⁴²¹-CTTN expression.

Curcuma Contra Cancer? Curcumin and Hodgkin's Lymphoma

Curcumin, a phytochemical isolated from curcuma plants which are used as coloring ingredient for the preparation of curry powder, has several activities which suggest that it might be an interesting drug for the treatment or prevention of cancer. Curcumin targets different pathways which are involved in the malignant phenotype of tumor cells, including the nuclear factor kappa B (NFKB) pathway. This pathway is deregulated in multiple tumor entities, including Hodgkin’s lymphoma (HL). Indeed, curcumin can inhibit growth of HL cell lines and increases the sensitivity of these cells for cisplatin. In this review we summarize curcumin activities with special focus on possible activities against HL cells.