Resveratrol Chemosensitizes TNF-β-Induced Survival of 5-FU-Treated Colorectal Cancer Cells

The role of tumor-associated macrophages in osteosarcoma progression - therapeutic implications

BACKGROUND

Osteosarcoma (OS) is the most common primary malignant bone tumor. Compared with previous treatment modalities, such as amputation, more recent comprehensive treatment modalities based on neoadjuvant chemotherapy combined with limb salvage surgery have improved the survival rates of patients. Osteosarcoma treatment has, however, not further improved in recent years. Therefore, attention has shifted to the tumor microenvironment (TME) in which osteosarcoma cells are embedded. Therapeutic targets in the TME may be key to improving osteosarcoma treatment. Tumor-associated macrophages (TAMs) are the most common immune cells within the TME. TAMs in osteosarcoma may account for over 50% of the immune cells, and may play important roles in tumorigenesis, angiogenesis, immunosuppression, drug resistance and metastasis. Knowledge on the role of TAMs in the development, progression and treatment of osteosarcoma is gradually improving, although different or even opposing opinions still remain.

CONCLUSIONS

TAMs may participate in the malignant progression of osteosarcoma through self-polarization, the promotion of blood vessel and lymphatic vessel formation, immunosuppression, and drug resistance. Besides, various immune checkpoint proteins expressed on the surface of TAMs, such as PD-1 and CD47, provide the possibility of the application of immune checkpoint inhibitors. Several clinical trials have been carried out and/or are in progress. Mifamotide and the immune checkpoint inhibitor Camrelizumab were both found to be effective in prolonging progression-free survival. Thus, TAMs may serve as attractive therapeutic targets. Targeting TAMs as a complementary therapy is expected to improve the prognosis of osteosarcoma. Further efforts may be made to identify potential beneficiaries of TAM-targeted therapies.

Resveratrol as Chemosensitizer Agent: State of Art and Future Perspectives

Resistance to chemotherapy still remains a major challenge in the clinic, impairing the quality of life and survival rate of patients. The identification of unconventional chemosensitizing agents is therefore an interesting aspect of cancer research. Resveratrol has emerged in the last decades as a fascinating molecule, able to modulate several cancer-related molecular mechanisms, suggesting a possible application as an adjuvant in cancer management. This review goes deep into the existing literature concerning the possible chemosensitizing effect of resveratrol associated with the most conventional chemotherapeutic drugs. Despite the promising effects observed in different cancer types in in vitro studies, the clinical translation still presents strong limitations due to the low bioavailability of resveratrol. Recently, efforts have been moved in the field of drug delivery to identifying possible strategies/formulations useful for a more effective administration. Despite the necessity of a huge implementation in this research area, resveratrol appears as a promising molecule able to sensitize resistant tumors to drugs, suggesting its potential use in therapy-refractory cancer patients.

Resveratrol's Anti-Cancer Effects through the Modulation of Tumor Glucose Metabolism

Simple Summary

The prevention and treatment of cancer is an ongoing medical challenge. In the context of personalized medicine, the well-studied polyphenol resveratrol could complement classical tumor therapy. It may affect key processes such as inflammation, angiogenesis, proliferation, metastasis, glucose metabolism, and apoptosis in various cancers because resveratrol acts as a multi-targeting agent by modulating multiple signal transduction pathways. This review article focuses on resveratrol’s ability to modify tumor glucose metabolism and its associated therapeutic capacity. Resveratrol reduces glucose uptake and glycolysis by affecting Glut1, PFK1, HIF-1α, ROS, PDH, and the CamKKB/AMPK pathway. It also inhibits cell growth, invasion, and proliferation by targeting NF-kB, Sirt1, Sirt3, LDH, PI-3K, mTOR, PKM2, R5P, G6PD, TKT, talin, and PGAM. In addition, resveratrol induces apoptosis by targeting integrin, p53, LDH, and FAK. In conclusion, resveratrol has many potentials to intervene in tumor processes if bioavailability can be increased and this natural compound can be used selectively.

Abstract

Tumor cells develop several metabolic reprogramming strategies, such as increased glucose uptake and utilization via aerobic glycolysis and fermentation of glucose to lactate; these lead to a low pH environment in which the cancer cells thrive and evade apoptosis. These characteristics of tumor cells are known as the Warburg effect. Adaptive metabolic alterations in cancer cells can be attributed to mutations in key metabolic enzymes and transcription factors. The features of the Warburg phenotype may serve as promising markers for the early detection and treatment of tumors. Besides, the glycolytic process of tumors is reversible and could represent a therapeutic target. So-called mono-target therapies are often unsafe and ineffective, and have a high prevalence of recurrence. Their success is hindered by the ability of tumor cells to simultaneously develop multiple chemoresistance pathways. Therefore, agents that modify several cellular targets, such as energy restriction to target tumor cells specifically, have therapeutic potential. Resveratrol, a natural active polyphenol found in grapes and red wine and used in many traditional medicines, is known for its ability to target multiple components of signaling pathways in tumors, leading to the suppression of cell proliferation, activation of apoptosis, and regression in tumor growth. Here, we describe current knowledge on the various mechanisms by which resveratrol modulates glucose metabolism, its potential as an imitator of caloric restriction, and its therapeutic capacity in tumors.

Targeting the tumor immune microenvironment with "nutraceuticals": From bench to clinical trials

The occurrence of immune effector cells in the tissue microenvironment during neoplastic progression is critical in determining tumor growth outcomes. On the other hand, tumors may also avoid immune system-mediated elimination by recruiting immunosuppressive leukocytes and soluble factors, which coordinate a tumor microenvironment that counteracts the efficiency of the antitumor immune response. Checkpoint inhibitor therapy results have indicated a way forward via activation of the immune system against cancer. Widespread evidence has shown that different compounds in foods, when administered as purified substances, can act as immunomodulators in humans and animals. Although there is no universally accepted definition of nutraceuticals, the term identifies a wide category of natural compounds that may impact health and disease statuses and includes purified substances from natural sources, plant extracts, dietary supplements, vitamins, phytonutrients, and various products with combinations of functional ingredients. In this review, we summarize the current knowledge on the immunomodulatory effects of nutraceuticals with a special focus on the cancer microenvironment, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of nutraceuticals for envisioning future therapies employing nutraceuticals as chemoadjuvants.

Inflammatory Responses in Oro-Maxillofacial Region Expanded Using Anisotropic Hydrogel Tissue Expander

OBJECTIVE

Reconstruction of oral and facial defects often necessitate replacement of missing soft tissue. The purpose of tissue expanders is to grow healthy supplementary tissue under a controlled force. This study investigates the inflammatory responses associated with the force generated from the use of anisotropic hydrogel tissue expanders.

METHODS

Sprague Dawley rats (n = 7, body weight = 300 g ± 50 g) were grouped randomly into two groups-control (n = 3) and expanded (n = 4). Anisotropic hydrogel tissue expanders were inserted into the frontal maxillofacial region of the rats in the expanded group. The rats were sacrificed, and skin samples were harvested, fixed in formalin, and embedded in paraffin wax for histological investigation. Hematoxylin and eosin staining was performed to detect histological changes between the two groups and to investigate the inflammatory response in the expanded samples. Three inflammatory markers, namely interleukin (IL)-1α, IL-6, and tumor necrosis factor-α (TNF-α), were analyzed by immunohistochemistry.

RESULT

IL-1-α expression was only observed in the expanded tissue samples compared to the controls. In contrast, there was no significant difference in IL-6, and TNF-α production. Histological analysis showed the absence of inflammatory response in expanded tissues, and a negative non-significant correlation (Spearman's correlation coefficient) between IL-1-α immune-positive cells and the inflammatory cells (r = -0.500). In conclusion, tissues that are expanded and stabilized using an anisotropic self-inflating hydrogel tissue expander might be useful for tissue replacement and engraftment as the expanded tissue does not show any sign of inflammatory responses. Detection of IL-1-α in the expanded tissues warrants further investigation for its involvement without any visible inflammatory response.

Resveratrol Suppresses Cross-Talk between Colorectal Cancer Cells and Stromal Cells in Multicellular Tumor Microenvironment: A Bridge between In Vitro and In Vivo Tumor Microenvironment Study

The interaction between tumor cells and the tumor microenvironment (TME) is an important process for the development of tumor malignancy. Modulation of paracrine cross-talk could be a promising strategy for tumor control within the TME. The exact mechanisms of multi-targeted compound resveratrol are not yet fully understood. Whether resveratrol can modulate paracrine signal transduction-induced malignancy in the multicellular-TME of colorectal cancer cells (CRC) was investigated. An in vitro model with 3D-alginate HCT116 cells in multicellular-TME cultures (fibroblast cells, T-lymphocytes) was used to elucidate the role of TNF-β, Sirt1-ASO and/or resveratrol in the proliferation, invasion and cancer stem cells (CSC) of CRC cells. We found that multicellular-TME, similar to TNF-β-TME, promoted proliferation, colony formation, invasion of CRC cells and enabled activation of CSCs. However, after co-treatment with resveratrol, the malignancy of multicellular-TME reversed to HCT116. In addition, resveratrol reduced the secretion of T-lymphocyte/fibroblast (TNF-β, TGF-β3) proteins, antagonized the T-lymphocyte/fibroblast-promoting NF-κB activation, NF-κB nuclear translocation and thus the expression of NF-κB-promoting biomarkers, associated with proliferation, invasion and survival of CSCs in 3D-alginate cultures of HCT116 cells induced by TNF-β- or multicellular-TME, but not by Sirt1-ASO, indicating the central role of this enzyme in the anti-tumor function of resveratrol. Our results suggest that in vitro multicellular-TME promotes crosstalk between CRC and stromal cells to increase survival, migration of HCT116 and the resveratrol/Sirt1 axis suppresses this loop by modulating paracrine agent secretion and NF-κB signaling. Fibroblasts and T-lymphocytes are promising targets for resveratrol in the prevention of CRC metastasis.

Inhibition of semaphorin 4D enhances chemosensitivity by increasing 5-fluorouracile-induced apoptosis in colorectal cancer cells

Overexpression of semaphorin 4D (SEMA4D), an immune semaphorin, is found in various human malignancies, including colorectal cancer (CRC). In this study, we explored the relationship between silencing SEMA4D expression and 5-fluorouracil (5-FU) response in the colorectal cancer cell line. SW48 cells were transfected with a short interfering RNA (siRNA) in order to silence SEMA4D gene expression and then exposed to 5-FU for 48 h. The down-regulation of SEMA4D expression was confirmed by qRT-PCR and the particular concentration of 5-FU was acquired using MTT assay. Flow cytometry and western blot were used to evaluate apoptosis rate and pro- and anti-apoptotic expression levels of proteins involved in apoptosis including Bax, Bcl-2, P53, and caspase-3. Other oncogenic activities including epithelial-mesenchymal transition (EMT) process, cancer stem cell (CSC) markers, and β-catenin pathway were investigated using qRT-PCR, and western blot. The proliferation was analyzed via colony formation test and cell invasion was assessed by transwell assay. Our data demonstrate that SEMA4D silencing results in strikingly elevated apoptosis in response to 5-FU treatment and leads to down-regulation of Bcl-2 and overexpression of Bax, P53, and caspase-3 in protein levels. Furthermore, the mRNA and protein expression levels of β-catenin, as well as transcript expressions of CSCs and EMT markers, were remarkably diminished. However, mRNA expression of E-cadherin as an epithelial marker was significantly increased in 5-FU treatment combined with siRNA SEMA4D. This study implicates that the silencing of SEMA4D by siRNA promotes the chemosensitivity of SW48 cells to 5-FU and it may be a potential therapeutic agent for colon cancer therapy.

Flavonoids and Related Members of the Aromatic Polyketide Group in Human Health and Disease: Do They Really Work?

Some aromatic polyketides such as dietary flavonoids have gained reputation as miraculous molecules with preeminent beneficial effects on human health, for example, as antioxidants. However, there is little conclusive evidence that dietary flavonoids provide significant leads for developing more effective drugs, as the majority appears to be of negligible medicinal importance. Some aromatic polyketides of limited distribution have shown more interesting medicinal properties and additional research should be focused on them. Combretastatins, analogues of phenoxodiol, hepatoactive kavalactones, and silymarin are showing a considerable promise in the advanced phases of clinical trials for the treatment of various pathologies. If their limitations such as adverse side effects, poor water solubility, and oral inactivity are successfully eliminated, they might be prime candidates for the development of more effective and in some case safer drugs. This review highlights some of the newer compounds, where they are in the new drug pipeline and how researchers are searching for additional likely candidates.

Targeting NF-κB Signaling by Calebin A, a Compound of Turmeric, in Multicellular Tumor Microenvironment: Potential Role of Apoptosis Induction in CRC Cells

Increasing lines of evidence suggest that chronic inflammation mediates most chronic diseases, including cancer. The transcription factor, NF-κB, has been shown to be a major regulator of inflammation and metastasis in tumor cells. Therefore, compounds or any natural agents that can inhibit NF-κB activation have the potential to prevent and treat cancer. However, the mechanism by which Calebin A, a component of turmeric, regulates inflammation and disrupts the interaction between HCT116 colorectal cancer (CRC) cells and multicellular tumor microenvironment (TME) is still poorly understood. The 3D-alginate HCT116 cell cultures in TME were treated with Calebin A, BMS-345541, and dithiothreitol (DTT) and examined for invasiveness, proliferation, and apoptosis. The mechanism of TME-induced malignancy of cancer cells was confirmed by phase contrast, Western blotting, immunofluorescence, and DNA-binding assay. We found through DNA binding assay, that Calebin A inhibited TME-induced NF-κB activation in a dose-dependent manner. As a result of this inhibition, NF-κB phosphorylation and NF-κB nuclear translocation were down-modulated. Calebin A, or IκB-kinase (IKK) inhibitor (BMS-345541) significantly inhibited the direct interaction of nuclear p65 to DNA, and interestingly this interaction was reversed by DTT. Calebin A also suppressed the expression of NF-κB-promoted anti-apoptotic (Bcl-2, Bcl-xL, survivin), proliferation (Cyclin D1), invasion (MMP-9), metastasis (CXCR4), and down-regulated apoptosis (Caspase-3) gene biomarkers, leading to apoptosis in HCT116 cells. These results suggest that Calebin A can suppress multicellular TME-promoted CRC cell invasion and malignancy by inhibiting the NF-κB-promoting inflammatory pathway associated with carcinogenesis, underlining the potential of Calebin A for CRC treatment.

Mechanisms of resveratrol in the prevention and treatment of gastrointestinal cancer

Gastrointestinal (GI) cancer is one of the leading causes of cancer-related deaths worldwide. According to the Global Cancer Statistics, colorectal cancer is the second leading cause of cancer-related mortality, closely followed by gastric cancer (GC). Environmental, dietary, and lifestyle factors including cigarette smoking, alcohol intake, and genetics are the most important risk factors for GI cancer. Furthermore, infections caused by Helicobacter pylori are a major cause of GC initiation. Despite improvements in conventional therapies, including surgery, chemotherapy, and radiotherapy, the length or quality of life of patients with advanced GI cancer is still poor because of delayed diagnosis, recurrence and side effect. Resveratrol (3, 4, 5-trihydroxy-trans-stilbene; Res), a natural polyphenolic compound, reportedly has various pharmacologic functions including anti-oxidant, anti-inflammatory, anti-cancer, and cardioprotective functions. Many studies have demonstrated that Res also exerts a chemopreventive effect on GI cancer. Research investigating the anti-cancer mechanism of Res for the prevention and treatment of GI cancer has implicated multiple pathways including oxidative stress, cell proliferation, and apoptosis. Therefore, this paper provides a review of the function and molecular mechanisms of Res in the prevention and treatment of GI cancer.

Recent Advances in Polymer Nanomaterials for Drug Delivery of Adjuvants in Colorectal Cancer Treatment: A Scientific-Technological Analysis and Review

Colorectal cancer (CRC) is the type with the second highest morbidity. Recently, a great number of bioactive compounds and encapsulation techniques have been developed. Thus, this paper aims to review the drug delivery strategies for chemotherapy adjuvant treatments for CRC, including an initial scientific-technological analysis of the papers and patents related to cancer, CRC, and adjuvant treatments. For 2018, a total of 167,366 cancer-related papers and 306,240 patents were found. Adjuvant treatments represented 39.3% of the total CRC patents, indicating the importance of adjuvants in the prognosis of patients. Chemotherapy adjuvants can be divided into two groups, natural and synthetic (5-fluorouracil and derivatives). Both groups can be encapsulated using polymers. Polymer-based drug delivery systems can be classified according to polymer nature. From those, anionic polymers have garnered the most attention, because they are pH responsive. The use of polymers tailors the desorption profile, improving drug bioavailability and enhancing the local treatment of CRC via oral administration. Finally, it can be concluded that antioxidants are emerging compounds that can complement today's chemotherapy treatments. In the long term, encapsulated antioxidants will replace synthetic drugs and will play an important role in curing CRC.

Synergistic enhancement of efficacy of platinum drugs with verteporfin in ovarian cancer cells

Background

Epithelial ovarian cancers (EOCs) comprises the majority of malignant ovarian neoplasms. Combination treatment with chemotherapeutic agents seems to be a promising strategy in ovarian cancer (OVCA) patients in order to overcome drug resistance. In this in vitro study, we investigated the therapeutic efficacy of verteporfin (VP) alone and in combination with cisplatin (CDDP), carboplatin (CP) and paclitaxel (Taxol). The main objectives of this study are to determine the nature of interactions between VP and CDDP/CP/Taxol and to understand the mechanism of action of VP in OVCA cells.

Methods

The efficacy of VP on cell proliferation, cytotoxicity, invasion and clonogenic capacity was assayed in CDDP-sensitive (COV504, OV-90) and CDDP-resistant (A2780Cis) cell lines. The cytotoxic effects of drugs either alone or in combination were evaluated using MTT assay and Cell Viability Blue assay. The effects of drugs on the metabolic functions were studied using matrigel invasion assay and clonogenic assay. Immunoblot analysis was carried out to investigate changes in YAP and cell cycle genes. Changes in the cytokines due to drug treatments were analyzed using a cytokine array.

Results

Treatment with VP inhibited cell proliferation, invasion and increased cytotoxicity of OVCA cells. We observed that VP chemosensitized CDDP-resistant cells, even at lower doses. When added either in constant or non-constant ratios, VP produced synergistic effects in combination with CDDP/CP/Taxol. A cytokine array identified upregulation of cytokines in OVCA cells that were inhibited by VP treatment.

Conclusions

Either in cisplatin-resistant cell lines or cisplatin-sensitive cell lines, VP proves to be more efficient in inhibiting cell proliferation and inducing cytotoxicity. Our results suggest that novel combinations of VP with CDDP or CP or Taxol might be an attractive therapeutic strategy to enhance OVCA chemosensitivity. The fact that lower doses of VP are effective in chemosensitizing the CDDP-resistant cells, might ultimately lead to the development of an innovative combination therapy for the treatment of OVCA patients.

Calebin A Potentiates the Effect of 5-FU and TNF-β (Lymphotoxin α) against Human Colorectal Cancer Cells: Potential Role of NF-κB

Objective: The majority of chemotherapeutic agents stimulate NF-κB signaling that mediates cell survival, proliferation and metastasis. The natural turmeric non-curcuminoid derivate Calebin A has been shown to suppress cell growth, invasion and colony formation in colorectal cancer cells (CRC) by suppression of NF-κB signaling. Therefore, we hypothesized here that Calebin A might chemosensitize the TNF-β-treated tumor cells and potentiates the effect of 5-Fluorouracil (5-FU) in advanced CRC. Materials and Methods: CRC cells (HCT116) and their clonogenic 5-FU chemoresistant counterparts (HCT116R) were cultured in monolayer or alginate-based 3D tumor environment culture and were treated with/without Calebin A, TNF-β, 5-FU, BMS-345541 and DTT (dithiothreitol). Results: The results showed that TNF-β increased proliferation, invasion and resistance to apoptosis in chemoresistant CRC cells. Pretreatment with Calebin A significantly chemosensitized HCT116R to 5-FU and inhibited the TNF-β-induced enhanced efforts for survival, invasion and anti-apoptotic effects. We found further that Calebin A significantly suppressed TNF-β-induced phosphorylation and nuclear translocation of p65-NF-κB, similar to BMS-345541 (specific IKK inhibitor) and NF-κB-induced tumor-promoting biomarkers (NF-κB, β1-Integrin, MMP-9, CXCR4, Ki67). This was associated with increased apoptosis in HCT116 and HCT116R cells. Furthermore, blocking of p65-NF-κB stimulation by Calebin A was imparted through the downmodulation of p65-NF-κB binding to the DNA and this suppression was turned by DTT. Conclusion: Our findings indicate, for the first time, that Calebin A chemosensitizes human CRC cells to chemotherapy by targeting of the p65-NF-κB signaling pathway.

Menopause-Associated Lipid Metabolic Disorders and Foods Beneficial for Postmenopausal Women

Menopause is clinically diagnosed as a condition when a woman has not menstruated for one year. During the menopausal transition period, there is an emergence of various lipid metabolic disorders due to hormonal changes, such as decreased levels of estrogens and increased levels of circulating androgens; these may lead to the development of metabolic syndromes including cardiovascular diseases and type 2 diabetes. Dysregulation of lipid metabolism affects the body fat mass, fat-free mass, fatty acid metabolism, and various aspects of energy metabolism, such as basal metabolic ratio, adiposity, and obesity. Moreover, menopause is also associated with alterations in the levels of various lipids circulating in the blood, such as lipoproteins, apolipoproteins, low-density lipoproteins (LDLs), high-density lipoproteins (HDL) and triacylglycerol (TG). Alterations in lipid metabolism and excessive adipose tissue play a key role in the synthesis of excess fatty acids, adipocytokines, proinflammatory cytokines, and reactive oxygen species, which cause lipid peroxidation and result in the development of insulin resistance, abdominal adiposity, and dyslipidemia. This review discusses dietary recommendations and beneficial compounds, such as vitamin D, omega-3 fatty acids, antioxidants, phytochemicals—and their food sources—to aid the management of abnormal lipid metabolism in postmenopausal women.

The Association Between Inflammation, Epithelial Mesenchymal Transition and Stemness in Colorectal Carcinoma

Background

Inflammation plays an important albeit dual role in carcinogenesis. Survival studies have highlighted the prognostic significance of peritumorous inflammation. Currently, the theoretical background allows inflammation, epithelial mesenchymal transition (EMT) and the closely associated stem cell differentiation in colorectal carcinoma (CRC) to be linked. However, there is scarce direct morphological evidence.

Purpose and methods

The aim of our study was to investigate the role of inflammation in cancer growth and invasion by analyzing the association between inflammation and known morphological prognostic features of colorectal cancer, EMT, stemness and mismatch repair (MMR) protein expression. The study was designed as a retrospective morphological and immunohistochemical assessment of 553 consecutive cases of surgically treated primary CRC.

Results

There were statistically significant associations between high-grade inflammation and lower pT (p = 0.002), absence of lymph node metastases (p < 0.001) and less frequent lymphatic (p = 0.003), venous (p = 0.017), arterial (p = 0.012), perineural (p = 0.001) and intraneural (p = 0.01) invasion. In contrast, Crohn's like reaction (CLR) by density of lymphoid follicles in the invasive front lacked significant differences in regard to pT, pN, tumor invasion into surrounding structures (blood or lymphatic vessels, nerves), grade or necrosis (all p > 0.05). The expression of E-cadherin, CD44 and MMR proteins yielded no statistically significant associations with peritumorous inflammation by Klintrup-Mäkinen score or the density of lymphoid follicles. Nevertheless, E-cadherin levels were significantly associated with the density of eosinophils (p = 0.007).

Conclusion

High-grade peritumorous inflammation is associated with beneficial morphologic CRC features, including less frequent manifestations of invasion, and is not secondary to tissue damage and necrosis. CLR is not associated with cancer spread by pTN; this finding indirectly suggests an independent role of CLR in carcinogenesis. Further, inflammation by Klintrup-Mäkinen grade and CLR is not dependent on epithelial-mesenchymal transition and stem cell differentiation. Our study highlights the complex associations between inflammation, tumor morphology, EMT, stemness and MMR protein expression in human CRC tissues.

Pro-apoptotic genes as new targets for single and combinatorial treatments with resveratrol and curcumin in colorectal cancer

Colorectal cancer (CRC) represents the third most diagnosed type of cancer worldwide with high mortality and an increased incidence rate. Bioactive dietary components such as curcumin and resveratrol have great therapeutic potential as they can modulate a plethora of signaling pathways related to colorectal carcinogenesis. Previous data have demonstrated that curcumin and resveratrol can induce apoptosis in different types of cancer cells. Considering the lack of data on the combinatorial effect of curcumin and resveratrol associated with the induction of apoptosis in colorectal pathology, the main objective of this study is to investigate the impact of single vs. combinatorial treatment of resveratrol and curcumin on their cytotoxic effects, as well as the modulation of several essential pro-apoptotic genes, on two colorectal cancer cell lines (DLD-1 and Caco-2) different in terms of chromosomal stability (MSI and MSS). The cytotoxic effects were evaluated by the MTT assay, the nature of the interaction between curcumin and resveratrol was assessed by the combination index method and the expression levels of key genes involved in the modulation of pro-apoptotic mechanisms were evaluated by RT-qPCR. Our data indicate that the combination treatment of curcumin and resveratrol is more effective in inhibiting the proliferation in a dose-dependent manner, with a synergistic effect for the DLD-1 cell line (CI < 1) and an additive effect for the Caco-2 cell line (CI ≥ 1). The IC50 values for the combination treatment were 71.8 μM (20.5 μM curcumin + 51.3 μM resveratrol) for the DLD-1 cell line and 66.21 μM (18.9 μM curcumin + 47.3 μM resveratrol) for the Caco-2 cell line, respectively. Our data pointed out, for the first time, that several genes involved in the modulation of apoptosis, including PMAIP1, BID, ZMAT3, CASP3, CASP7, and FAS, represent new targets of both singular and combinatorial treatments with resveratrol and curcumin, and also the combinatorial approach of curcumin and resveratrol exhibits a more powerful gene regulating effect compared to single treatment. Considering the beneficial aspects of the combinatorial approach with curcumin and resveratrol on colorectal cancer cells further studies should address the possible pharmacological benefits of using a combination of both dietary agents with different chemotherapeutic drug approaches.

Evidence That Calebin A, a Component of Curcuma Longa Suppresses NF-B Mediated Proliferation, Invasion and Metastasis of Human Colorectal Cancer Induced by TNF-β (Lymphotoxin)

Objective: Natural polyphenol Calebin A has been recently discovered as a novel derivate from turmeric with anti-cancer potential. Pro-inflammatory cytokine TNF-β (lymphotoxin α) is a stimulant for cancer cell malignity via activation of NF-κB pathway, also in colorectal cancer (CRC). Here, we investigated the potential of Calebin A to suppress TNF-β-induced NF-κB signalling in CRC. Materials and Methods: Three distinct CRC cell lines (HCT116, RKO, SW480) were treated in monolayer or 3-dimensional alginate culture with TNF-β, Calebin A, curcumin, BMS-345541, dithiothreitol (DTT) or antisense oligonucleotides-(ASO) against NF-κB. Results: Calebin A suppressed dose-dependent TNF-β-induced CRC cell vitality and proliferation in monolayer culture. Further, in alginate culture, Calebin A significantly suppressed TNF-β-enhanced colonosphere development, as well as invasion and colony formation of all three CRC cell lines investigated. Calebin A specifically blocked TNF-β-induced activation and nuclear translocation of p65-NF-κB, similar to curcumin (natural NF-κB inhibitor), BMS-345541 (specific IKK inhibitor) and ASO-NF-κB. Moreover, Immunofluorescence and Immunoblotting showed that Calebin A, similar to curcumin or BMS-345541 suppressed TNF-β-induced activation and nuclear translocation of p65-NF-κB and the transcription of NF-κB-promoted biomarkers associated with proliferation, migration and apoptosis, in a dose- and time-dependent manner. Those findings were potentiated by the specific treatment of extracted nuclei with DTT, which abrogated Calebin A-mediated nuclear p65-NF-κB-inhibition and restored p65-NF-κB-activity in the nucleus. Conclusion: Overall, these results demonstrate, for the first time, that multitargeted Calebin A has an anti-cancer capability on TNF-β-induced malignities through inhibitory targeting of NF-κB activation in the cytoplasm, as well as by suppressing the binding of p65-NF-κB to DNA.

Th1, Th2, and Th17 cytokines in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the breakdown of immune tolerance leading to excessive inflammation and tissue damage. Imbalance in the levels of cytokines represents one of the multifactorial causes of SLE pathogenesis and it contributes to disease severity. Deregulated levels of T helper type 1 (Th1), type 2 (Th2), and type 17 (Th17) cytokines have been associated with autoimmune inflammation. Growing evidence has shown deregulated levels of Th1, Th2, and Th17 cytokines in SLE patients compared to healthy controls associated with disease activity and severity. In this review, we describe and discuss the levels of Th1, Th2, and Th17 cytokines in SLE patients, and clinical trials involving Th1, Th2, and Th17 cytokines in SLE patients. In particular, with the exception of IL-2, IL-4, and TGF-β1, the levels of Th1, Th2, and Th17 cytokines are increased in SLE patients associated with disease severity. Current phase II or III studies involve therapeutic antibodies targeting IFN-α and type I IFN receptor, while low-dose IL-2 therapy is assessed in phase II clinical trials.

Modulation of Multiple Signaling Pathways of the Plant-Derived Natural Products in Cancer

Natural compounds are highly effective anticancer chemotherapeutic agents, and the targets of plant-derived anticancer agents have been widely reported. In this review, we focus on the main signaling pathways of apoptosis, proliferation, invasion, and metastasis that are regulated by polyphenols, alkaloids, saponins, and polysaccharides. Alkaloids primarily affect apoptosis-related pathways, while polysaccharides primarily target pathways related to proliferation, invasion, and metastasis. Other compounds, such as flavonoids and saponins, affect all of these aspects. The association between compound structures and signaling pathways may play a critical role in drug discovery.

Resveratrol is a promising agent for colorectal cancer prevention and treatment: focus on molecular mechanisms

Colorectal cancer (CRC) is the third most common cancer and one of the main causes of cancer death entire the world. Environmental, dietary, and lifestyle factors including red meat consumption, cigarette smoking, alcohol intake and family history are the most important risk factors of CRC. Multiple pathways including inflammation, oxidative stress, and apoptosis are involved in its incidence and progression. Resveratrol, a polyphenolic compound, has different pharmacologic functions including anti-inflammation, cancer prevention, lipid-lowering effect, and hypoglycemic effect. Many studies have proved that resveratrol might also represent a chemo preventive effect on CRC. Thus, the aim of the current review is to depict the role of resveratrol in treatment of CRC in a molecular manner.

Isobavachalcone isolated from Psoralea corylifolia inhibits cell proliferation and induces apoptosis via inhibiting the AKT/GSK-3β/β-catenin pathway in colorectal cancer cells

Background: Colorectal cancer (CRC) is a common form of cancer associated with a high mortality rate and poor prognosis. Given the limited efficacy of current therapies for CRC, interest in novel therapeutic agents isolated from natural sources has increased. We studied the anticancer properties of isobavachalcone (IBC), a flavonoid isolated from the herb Psoralea corylifolia, which is used in traditional Chinese medicine, in an in vitro model of CRC.

Materials and methods: Cell viability and growth of CRC cells were determined by Cell Counting Kit-8 and colony formation assays following treatment with varying concentrations of IBC, respectively. Apoptosis was examined by 4′,6-diamidino-2-phenylindole staining and flow cytometry with Annexin V/propidium iodide double staining. Western blot analysis was used to analyze expression of apoptosis-associated protein pathway and the AKT/GSK-3β/β-catenin signaling pathway.

Results: Initial experiments showed that IBC inhibited proliferation and colony formation of human CRC cell lines in dose- and time-dependent manners. The antiproliferative effect of IBC resulted from induction of apoptosis, as evidenced by morphological changes in the nucleus, flow cytometry analysis, upregulation of cleaved caspase-3 and cleaved PARP, changes in the ratio of the anti-apoptotic protein Bcl-2 and the pro-apoptotic protein Bax, translocation of Bax from the cytosol to the mitochondria, and decreased expression of two inhibitors of apoptosis family proteins, XIAP, and survivin. Western blot analysis of signaling pathway proteins demonstrated that IBC downregulated Wnt/β-catenin signaling, which has previously been associated with CRC, by inhibiting the AKT/GSK-3β signaling pathway.

Conclusion: This study demonstrated that IBC inhibited cell proliferation and induced apoptosis through inhibition of the AKT/GSK-3β/β-catenin pathway in CRC. These results suggest the potential of IBC as a novel therapeutic agent for the treatment of CRC.

Induction of the Epithelial-to-Mesenchymal Transition of Human Colorectal Cancer by Human TNF-β (Lymphotoxin) and its Reversal by Resveratrol

Objective: Tumor necrosis factor-beta (TNF-β), as an inflammatory mediator that has been shown to promote tumorigenesis, induces NF-κB. Natural multi-targeted agent resveratrol in turn shows anti-inflammatory and anti-cancer properties. Epithelial-to-mesenchymal transition (EMT) allows cancer cells to turn into a motile state with invasive capacities and is associated with metastasis and development of cancer stem cells (CSC). However, TNF-β-induced EMT and the anti-invasion mechanism of resveratrol on CRC are not yet completely understood. Methods: We investigated the underlying molecular mechanisms of resveratrol on TNF-β/TNF-βR-induced EMT and migration of CRC cells (HCT116, RKO, SW480) in monolayer or 3D alginate cultures. Results: TNF-β, similar to TNF-α, induced significant cell proliferation, morphological change, from an epithelial to a spindle-like mesenchymal shape with the formation of filopodia and lamellipodia associated with the expression of EMT parameters (elevated vimentin and slug, reduced E-cadherin), increased migration/invasion, and formation of CSC in all CRC cells. Interestingly, these effects were dramatically decreased in the presence of resveratrol or anti-TNF-βR with TNF-β co-treatment, inducing biochemical changes to the mesenchymal-epithelial transition (MET), with a planar cell surface and suppressed formation of CSC cells. This was associated with a significant increase in apoptosis. Furthermore, we found that resveratrol suppressed TNF-β-induced NF-κB and NF-κB-regulated gene biomarkers associated with growth, proliferation, and invasion. Finally, TNF-βR interacts directly with focal adhesion kinase (FAK) and NF-κB. Conclusion: These results suggest that resveratrol down-regulates TNF-β/TNF-βR-induced EMT, at least in part via specific suppression of NF-κΒ and FAK in CRC cells.

Resveratrol as a Tumor-Suppressive Nutraceutical Modulating Tumor Microenvironment and Malignant Behaviors of Cancer

Tumor-suppressive effects of resveratrol have been shown in various types of cancer. However, regulation of tumor microenvironment by resveratrol is still unclear. Recent findings suggest resveratrol can potentiate its tumor-suppressive effect through modulation of the signaling pathways of cellular components (fibroblasts, macrophages and T cells). Also, studies have shown that resveratrol can suppress malignant phenotypes of cancer cells acquired in response to stresses of the tumor microenvironment, such as hypoxia, oxidative stress and inflammation. We discuss the effects of resveratrol on cancer cells in stress environment of tumors as well as interactions between cancer cells and non-cancer cells in this review.

Low let-7d and high miR-205 expression levels positively influence HNSCC patient outcome

Introduction

Head and neck squamous carcinoma (HNSCC) is one of the most invasive types of cancer with high mortality. A previous study has indicated that low levels of let-7d and miR-205 in HNSCC patients are correlated with poor survival. Let-7d and miR-205 are tumor suppressors and regulators of epithelial-to-mesenchymal transition (EMT). However, it is unclear if let-7d and miR-205 together influence cancer cells.

Aim

To determine if let-7d and miR-205 expression levels influence HNSCC patient outcome.

Methods

The TCGA expression data for let-7d, miR-205 and their targets as well as clinical data were downloaded from cBioPortal and starBase v2.0 for 307 patients. The expression levels of let-7d and miR-205 were verified according to clinicopathological parameters. The let-7d and miR-205 high- and low-expression groups as well as disease-free survival (DFS), overall survival (OS) and expression levels of genes related to EMT, cancer stem cells, metastasis, cell cycle, drug response and irradiation response were investigated.

Results

Let-7d and miR-205 were frequently upregulated in HNSCC compared to normal samples, and ROC analysis showed high discrimination ability for let-7d and miR-205 (area 0.7369 and 0.7739, respectively; p < 0.0001). Differences between expression levels of let-7d or miR-205 and grade, angiolymphatic invasion, perineural invasion and alcohol consumption were indicated. No differences were observed in N-stage, tumor localization, gender or patient age. Patients with lower let-7d levels and higher miR-205 levels had significantly better OS (p = 0.0325) than patients with higher let-7d levels and lower miR-205 levels. In the low let-7d level and high miR-205 level group, a lower percentage of more advanced cancers was observed. The analysis of genes related to EMT, cancer stem cells, metastasis, cell cycle, drug response and irradiation response revealed a distinct phenotype of analyzed groups.

Conclusions

The present findings indicated that let-7d down-regulation and miR-205 overexpression create a unique cell phenotype with different behavior compared to cells with upregulated let-7d and down-regulated miR-205. Thus, let-7d and miR-205 are good candidates for new HNSCC biomarkers.

Inhibition of NF-κB Signaling Pathway by Resveratrol Improves Spinal Cord Injury

Spinal cord injury (SCI) can have a significant impact on an individual’s life. Herein, we discuss how resveratrol improves SCI by inhibiting nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway. Evidences show resveratrol suppresses NF-κB signaling pathway to exert its beneficial effects on various diseases. NF-κB signaling pathway plays a significant role in the pathophysiological mechanisms of SCI including increase in inflammation, augmentation of damage caused by free radicals and lipid peroxidation as well as facilitation of apoptosis and axonal demyelination. We also discuss mechanisms between resveratrol and NF-κB signaling pathway in the wake of SCI, which can be potential targets for resveratrol to treat SCI.

Wnt Signalling-Targeted Therapy in the CMS2 Tumour Subtype: A New Paradigm in CRC Treatment?

Colorectal cancers (CRC) belonging to the consensus molecular subtype 2 (CMS2) have the highest incidence rate, affect mainly the distal colon and rectum, and are characterized by marked Wnt/β-catenin/Transcription Factor 7-Like 2 (TCF7L2) pathway activation and also by activation of epidermal growth factor receptor (EGFR) signalling. Despite having the highest overall survival, CMS2 tumours are often diagnosed at stage III when an adjuvant chemotherapy-based regimen is recommended. Nevertheless, colorectal cancer stem cells (CSCs) and circulating tumour cells may still evade the current therapeutic options and metastasize, stressing the need to develop more tailored therapeutic strategies. For example, activation of EGFR signalling is being used as a target for tailored therapy, however, therapy resistance is frequently observed. Therefore, targeting the Wnt signalling axis represents an additional therapeutic strategy, considering that CMS2 tumours are "Wnt-addicted". Several efforts have been made to identify Wnt antagonists, either of synthetic or natural origin. However, an inverse gradient of Wnt/β-catenin/TCF7L2 signalling activity during CRC progression has been suggested, with early stage and metastatic tumours displaying high and low Wnt signalling activities, respectively, which lead us to revisit the "just-right" signalling model. This may pinpoint the use of Wnt signalling agonists instead of antagonists for treatment of metastatic stages, in a context-dependent fashion. Moreover, the poor immunogenicity of these tumours challenges the use of recently emerged immunotherapies. This chapter makes a journey about CMS2 tumour characterization, their conventional treatment, and how modulation of Wnt signalling or immune response may be applied to CRC therapy. It describes the newest findings in this field and indicates where more research is required.