Efficacy of melatonin, IL-25 and siIL-17B in tumorigenesis-associated properties of breast cancer cell lines

Melatonin: a modulator in metabolic rewiring in T-cell malignancies

Melatonin, (N-acetyl-5-methoxytryptamine) an indoleamine exerts multifaced effects and regulates numerous cellular pathways and molecular targets associated with circadian rhythm, immune modulation, and seasonal reproduction including metabolic rewiring during T cell malignancy. T-cell malignancies encompass a group of hematological cancers characterized by the uncontrolled growth and proliferation of malignant T-cells. These cancer cells exhibit a distinct metabolic adaptation, a hallmark of cancer in general, as they rewire their metabolic pathways to meet the heightened energy requirements and biosynthesis necessary for malignancies is the Warburg effect, characterized by a shift towards glycolysis, even when oxygen is available. In addition, T-cell malignancies cause metabolic shift by inhibiting the enzyme pyruvate Dehydrogenase Kinase (PDK) which in turn results in increased acetyl CoA enzyme production and cellular glycolytic activity. Further, melatonin plays a modulatory role in the expression of essential transporters (Glut1, Glut2) responsible for nutrient uptake and metabolic rewiring, such as glucose and amino acid transporters in T-cells. This modulation significantly impacts the metabolic profile of T-cells, consequently affecting their differentiation. Furthermore, melatonin has been found to regulate the expression of critical signaling molecules involved in T-cell activations, such as CD38, and CD69. These molecules are integral to T-cell adhesion, signaling, and activation. This review aims to provide insights into the mechanism of melatonin's anticancer properties concerning metabolic rewiring during T-cell malignancy. The present review encompasses the involvement of oncogenic factors, the tumor microenvironment and metabolic alteration, hallmarks, metabolic reprogramming, and the anti-oncogenic/oncostatic impact of melatonin on various cancer cells.

Dual Functions of T Lymphocytes in Breast Carcinoma: From Immune Protection to Orchestrating Tumor Progression and Metastasis

Breast cancer (BC) is the most common cancer type in women and the second leading cause of death. Despite recent advances, the mortality rate of BC is still high, highlighting a need to develop new treatment strategies including the modulation of the immune system and immunotherapies. In this regard, understanding the complex function of the involved immune cells and their crosstalk with tumor cells is of great importance. T-cells are recognized as the most important cells in the tumor microenvironment and are divided into several subtypes including helper, cytotoxic, and regulatory T-cells according to their transcription factors, markers, and functions. This article attempts to provide a comprehensive review of the role of T-cell subsets in the prognosis and treatment of patients with BC, and crosstalk between tumor cells and T-cells. The literature overwhelmingly contains controversial findings mainly due to the plasticity of T-cell subsets within the inflammatory conditions and the use of different panels for their phenotyping. However, investigating the role of T-cells in BC immunity depends on a variety of factors including tumor types or subtypes, the stage of the disease, the localization of the cells in the tumor tissue and the presence of different cells or cytokines.

New insights into the function of Interleukin-25 in disease pathogenesis

Interleukin-25 (IL-25), also known as IL-17E, is a cytokine belonging to the IL-17 family. IL-25 is abundantly expressed by Th2 cells and various kinds of epithelial cells. IL-25 is an alarm signal generated upon cell injury or tissue damage to activate immune cells through the interaction with IL-17RA and IL-17RB receptors. The binding of IL-25 to IL-17RA/IL-17RB complex not only initiates and maintains type 2 immunity but also regulates other immune cells (e.g., macrophages and mast cells) via various signaling pathways. It has been well-documented that IL-25 is critically involved in the development of allergic disorders (e.g., asthma). However, the roles of IL-25 in the pathogenesis of other diseases and the underlying mechanisms are still unclear. This review presents current evidence on the roles of IL-25 in cancers, allergic disorders, and autoimmune diseases. Moreover, we discuss the unanswered key questions underlying IL-25-mediated disease pathology, which will provide new insights into the targeted therapy of this cytokine in clinical treatment.

Antitumor effect of melatonin on breast cancer in experimental models: A systematic review

Breast cancer is the most frequent malignant neoplasm in females. While conventional treatments such as chemotherapy and radiotherapy are available, they are highly invasive and toxic to oncological patients. Melatonin is a promising molecule for the treatment of breast cancer with antitumor effects on tumorigenesis and tumor progression. The aim of this systematic review was to synthesize knowledge about the antitumor effect of melatonin on breast cancer in experimental models and propose the main mechanisms of action already described in relation to the processes regulated by melatonin. PubMed, Web of Science, and Embase databases were used. The inclusion criteria were in vitro and in vivo experimental studies that used different formulations of melatonin as a treatment for breast cancer, without year or language restrictions. Risk of bias for studies was assessed using the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) tool. Data from selected articles were presented as narrative descriptions and tables. Seventy-five articles on different breast cancer cell lines and experimental models treated with melatonin alone, or in combination with other compounds were included. Melatonin showed antitumor effects on proliferative pathways related to the cell cycle and tumorigenesis, tumor death, angiogenesis, and tumor metastasis, as well as on oxidative stress and immune regulatory pathways. These effects were either dependent or independent of melatonin receptors. Herein, we clarify the antitumor action of melatonin on different tumorigenic processes in breast cancer in experimental models. Systematic review registration: PROSPERO database (CRD42022309822/https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022309822).

Interactions of melatonin with various signaling pathways: implications for cancer therapy

Melatonin is a neuro-hormone with conserved roles in evolution. Initially synthetized as an antioxidant molecule, it has gained prominence as a key molecule in the regulation of the circadian rhythm. Melatonin exerts its effect by binding to cytoplasmic and intra-nuclear receptors, and is able to regulate the expression of key mediators of different signaling pathways. This ability has led scholars to investigate the role of melatonin in reversing the process of carcinogenesis, a process in which many signaling pathways are involved, and regulating these pathways may be of clinical significance. In this review, the role of melatonin in regulating multiple signaling pathways with important roles in cancer progression is discussed, and evidence regarding the beneficence of targeting malignancies with this approach is presented.

Pro-Apoptotic and Anti-Migration Properties of a Thiazoline-Containing Platinum(II) Complex in MDA-MB-231 Breast Cancer Cells: The Role of Melatonin as a Synergistic Agent

Triple-negative breast cancer (TNBC) is an aggressive cancer insensitive to hormonal and human epidermal growth factor receptor 2 (HER2)-targeted therapies and has a poor prognosis. Therefore, there is a need for the development of convenient anticancer strategies for the management of TNBC. In this paper, we evaluate the antitumoral potential of a platinum(II) complex coordinated with the ligand 2-(3,5-diphenylpyrazol-1-yl)-2-thiazoline (DPhPzTn), hereafter PtDPhPzTn, against the TNBC cell line MDA-MB-231, and compared its effect with both cisplatin and its less lipophilic counterpart PtPzTn, the latter containing the ligand 2-(pyrazol-1-yl)-2-thiazoline (PzTn). Then, the putative potentiating actions of melatonin, a naturally occurring antioxidant with renowned antitumor properties, on the tumor-killing ability of PtDPhPzTn were also checked in TNBC cells. Our results show that PtDPhPzTn presented enhanced cytotoxicity compared to both the classical drug cisplatin and PtPzTn. In addition, PtDPhPzTn was able to induce apoptosis, being more selective for MDA-MB-231 cells when compared to non-tumor breast epithelial MCF10A cells. Likewise, PtDPhPzTn produced moderate S phase arrest and greatly impaired the migration ability of MDA-MB-231 cells. Most importantly, the co-stimulation of TNBC cells with PtDPhPzTn and melatonin substantially enhanced apoptosis and markedly improved the anti-migratory action compared to PtDPhPzTn alone. Altogether, our findings provide evidence that PtDPhPzTn and melatonin could be potentially applied to breast cancer treatment as powerful synergistic agents.

Molecular and cellular mechanisms of melatonin in breast cancer

Breast cancer is considered as one of the most important health problems due to its poor prognosis and high rate of mortality and new diagnosed cases. Annually, a great number of deaths are reported in men and women; this means that despite all the improvements in cancer diagnosis and treatment, still, an intense need for more effective approaches exists. Melatonin is a multivalent compound which has a hand in several cellular and molecular processes and therefore, is an appropriate candidate for treatment of many diseases like cancer. Currently, considerable properties of this agent have oriented the research towards investigating its effects specifically in breast cancer. In this review, we gathered a bunch of evidence in order to give a new sight for breast cancer treatment utilizing melatonin. We expect that in coming years, melatonin will become one of the most common therapeutic drugs with lesser side-effects than other chemotherapeutic drugs.

Modulation of Epithelial Mesenchymal Transition after AGTR-1 Gene Edition by Crispr/Cas9 and Losartan Treatment in Mammary Tumor Cell Line: A Comparative Study between Human and Canine Species

Breast cancer is the most prevalent tumor type among women and female dogs. Tumor malignancy is characterized by the epithelial-to-mesenchymal transition (EMT) which leads to the metastasis formation. The inhibition of angiotensin II type I receptor (AGTR1) by an antagonist such as losartan can suppress angiogenesis, consequently contributing to the metastasis control. The aim of this study was to analyze the capacity of losartan and AGTR-1 gene edition to modulate the EMT process in triple negative/metastatic mammary tumor cells, compared to existing treatment protocols such as carboplatin. The cell lines CF41.Mg and MDA-MB-468, were cultured and treated with carboplatin, losartan, or submitted to AGTR-1 gene edition by CRISPR/Cas9. EMT markers and PARP-1 protein and gene expression were evaluated by immunofluorescence or immunocytochemistry and qRT-PCR, respectively. Cell migration capacity was also evaluated. For CF41.Mg and MDA-MB-468 cell lines, there was an increase in E-cadherin and a decrease in N-cadherin and PARP-1 protein and gene expression after treatment with carboplatin, losartan, both in combination and after AGTR-1 gene edition. There was a decrease in VEGF and PARP-1 protein and gene expression after AGTR-1 gene edition. Moreover, in both lines, reduction in invasion rate was observed after all treatments. Our data suggest that losartan and the gene edition of AGTR-1 by CRISPR/Cas9 were able to block the DNA repair and control the EMT process, such as carboplatin. The results in the canine species are unprecedented, as there are no data in the literature that demonstrate the action of losartan in this tumor type.

Multifunctional Nanoparticles Loaded with Vascular Endothelial Growth Factor Inhibitors and MED1 siRNA to Inhibit Breast Cancer Progression by Targeting Tumor-Associated Macrophages and Breast Cancer Cells

Breast cancer is still threatening many people' lives, hence novel targeted therapies are urgently required to improve the poor outcome of breast cancer patients. Herein, our study aimed to explore the potential of nanoparticles (NPs)-loaded with VEGF inhibitors and MED1 siRNA for treatment of the disorder. PEG and MTC conjugates were synthesized by ion gelation, and equipped with VEGF inhibitor (siV) and MED1 (siD) siRNA (MT/PC/siV-D NPs). The size and morphology of the NPs were detected by TEM. Agarose gel experiment was performed to detect drug encapsulation rate and NPs stability. Zeta potential was assessed by immunofluorescence assay and cell uptake was detected by fluorescence analysis. After cancer cells were treated with NPs or PBS, cell proliferation and invasion were evaluated with VEGF and MED1 expression was detected by Western blot and RT-qPCR analyses. Animal model was conducted to confirm the role of NPs in tumor growth. Results showed that, the MT/PC/siV-D NPs exhibited great stability, drug encapsulation and internalization ability. The combined NPs caused decreased proliferation and invasion of tumor cells, inducing M2 macrophages to re-polarize to M1 type with declined expression of VEGF and MED1. Moreover, the NPs remarkably alleviated breast tumor progression. The multifunctional NPs equipped with EGF inhibitors and MED1 siRNA can inhibit tumor progression by targeting TAMs and cancer cells during breast cancer.

Treatment of Triple Negative Cell Lines with Olaparib to Block DNA Repair

BACKGROUND

The most aggressive breast cancer is the triple negative histological type and the gold standard for its treatment is platinum salts, such as carboplatin. Due to high recurrence, there is a need to test new drugs, such as PARP inhibitors (PARPi) that induce lethality in cells with DNA damage. Olaparib is a PARPi, already used in some tumors, but not tested in canine species. Thus, the aim of this study was demonstrating the efficacy of olaparib in inhibiting DNA repair and controlling disease progression by decreasing the migration capacity of mammary tumor cells.

METHODS

The cell lines, CF41.Mg and MDA-MB-468, were cultured and was performed the MTT to define the best dose of carboplatin. Next, the cells were treated with 10 µM carboplatin, olaparib and with combination of both for 24 hours. PARP-1 protein and gene expression was evaluated by immunofluorescence, western blotting and qRT-PCR, respectively. The analysis of cell migration was performed in transwell chambers.

RESULTS

For CF41.Mg and MDA-MB-468 cell lines, there was decrease in PARP-1 protein and gene expression after treatment with carboplatin, olaparib and both in combination compared to the group without treatment (control) (p<0.05). Moreover, in both lines, reduction in invasion rate was observed after treatment with carboplatin, olaparib and when combined, compared to the control group (p<0.05).

CONCLUSION

Our data suggests that carboplatin and olaparib were able to block DNA repair and control the cancer invasion, especially when used in combination. The results with olaparib in the canine line are unpublished. The olaparib should be a possible agent against human breast cancer and canine mammary tumors.

Interleukin-25: New perspective and state-of-the-art in cancer prognosis and treatment approaches

Cancer is a leading cause of death which imposes a substantial financial burden. Among the several mechanisms involved in cancer progression, imbalance of immune cell-derived factors such as cytokines and chemokines plays a central role. IL-25, as a member of the IL-17 cytokine subfamily, exerts a paradoxical role in cancer, including tumor supportive and tumor suppressive. Hence, we have tried to clarify the role of IL-25 and its receptor in tumor progression and cancer prognosis. It has been confirmed that IL-25 exerts a tumor-suppressive role through inducing infiltration of eosinophils and B cells into the tumor microenvironment and activating the apoptotic pathways. In contrast, the tumor-supportive function has been implemented by activating inflammatory cascades, promoting cell cycle, and inducing type-2 immune responses. Since IL-25 has been dysregulated in tumor tissues and this dysregulation is involved in cancer development, its examination can be used as a tumor diagnostic and prognostic biomarker. Moreover, IL-25-based therapeutic approaches have shown promising results in cancer inhibition. In cancers in which IL-25 has a tumor-suppressive function, employing IL-25-enhancing approaches, such as Virulizin® and dihydrobenzofuran administration, has potentially inhibited tumor cell growth. On the other hand, in the case of IL-25-dependent tumor progression, using IL-25 blocking methods, including anti-IL-25 antibodies, might be a complementary approach to the other anticancer agent. Collectively, it is hoped, IL-25 might be a promising target in cancer treatment.

IL-25 promotes trophoblast proliferation and invasion via binding with IL-17RB and associated with PE

INTRODUCTION

Interleukin-25 is a Th2 interleukin and has been shown to influence cell behavior. This study aims to illustrate its affection on extravillous trophoblasts function and association with PE. Methods qPCR and immunohistochemistry demonstrate IL-25 and IL-17RB expression. CCK-8 test and transwell were to access the behavior of HTR8 in the presence or absence of IL-25, IL-25 neutralization antibody. Results EVTs and HTR8 express IL-25 and IL-17RB. IL-25 promotes proliferation and invasion (p< 0.05),which was abolished in the presence of IL-25Ab (p< 0.05). Conclusion: IL-25 may contribute to promote trophoblast invasion and proliferation and abnormal decline of IL-25 might be associated with PE.

METHODS

qPCR and immunohistochemistry (IHC) were used to demonstrate IL-25 and its receptor IL-17RB expression in primary human trophoblasts of normal first- and third- trimester, as well as third-trimester of PE. CCK-8 test and transwell invasion system in vitro were applied separately to access the behavior of trophoblast cell line (HTR8) in the presence or absence of IL-25, IL-25 neutralization antibody (IL-25 Ab).

RESULTS

EVTs and HTR8 express IL-25 and IL-17RB. The expressions increase in third-trimester during normal pregnancy. In PE, both of IL-25 and IL-17RB expressions decrease (p< 0.05). IL-25 for 24 h promoted HTR8 proliferation and invasion (p< 0.05). The effect was abolished in the presence of IL-25Ab (p< 0.05).

CONCLUSION

This study demonstrates that IL-25 may contribute to promote trophoblast invasion and proliferation and abnormal decline of IL-25 might be associated with PE.

An updated review of mechanistic potentials of melatonin against cancer: pivotal roles in angiogenesis, apoptosis, autophagy, endoplasmic reticulum stress and oxidative stress

Cancers are serious life-threatening diseases which annually are responsible for millions of deaths across the world. Despite many developments in therapeutic approaches for affected individuals, the rate of morbidity and mortality is high. The survival rate and life quality of cancer patients is still low. In addition, the poor prognosis of patients and side effects of the present treatments underscores that finding novel and effective complementary and alternative therapies is a critical issue. Melatonin is a powerful anticancer agent and its efficiency has been widely documented up to now. Melatonin applies its anticancer abilities through affecting various mechanisms including angiogenesis, apoptosis, autophagy, endoplasmic reticulum stress and oxidative stress. Regarding the implication of mentioned cellular processes in cancer pathogenesis, we aimed to further evaluate the anticancer effects of melatonin via these mechanisms.

Melatonin: A Potential Therapeutic Option for Breast Cancer

Melatonin has significant inhibitory effects in numerous cancers, especially breast cancer. In estrogen receptor (ER)-positive human breast cancer, the oncostatic actions of melatonin are mainly achieved by suppressing ER mRNA expression and ER transcriptional activity via the MT1 receptor. Melatonin also regulates the transactivation of nuclear receptors, estrogen-metabolizing enzymes, and the expression of related genes. Furthermore, melatonin suppresses tumor aerobic glycolysis, critical cell-signaling pathways relevant to cell proliferation, survival, metastasis, and overcomes drug resistance. Studies in animal and human models indicate that disruption of the circadian nocturnal melatonin signal promotes the growth, metabolism, and signaling of human breast cancer, resulting in resistance to hormone therapy and chemotherapy, which may be reversed by melatonin.

Regulation of cancer cell glucose metabolism is determinant for cancer cell fate after melatonin administration

Several oncogenic pathways plus local microenvironmental conditions, such as hypoxia, converge on the regulation of cancer cells metabolism. The major metabolic alteration consists of a shift from oxidative phosphorylation as the major glucose consumer to aerobic glycolysis, although most of cancer cells utilize both pathways to a greater or lesser extent. Aerobic glycolysis, together with the directly related metabolic pathways such as the tricarboxylic acid cycle, the pentose phosphate pathway, or gluconeogenesis are currently considered as therapeutic targets in cancer research. Melatonin has been reported to present numerous antitumor effects, which result in a reduced cell growth. This is achieved with both low and high concentrations with no relevant side effects. Indeed, high concentrations of this indolamine reduce proliferation of cancer types resistant to low concentrations and induce cell death in some types of tumors. Previous work suggest that regulation of glucose metabolism and other related pathways play an important role in the antitumoral effects of high concentration of melatonin. In the present review, we analyze recent work on the regulation by such concentrations of this indolamine on aerobic glycolysis, gluconeogenesis, the tricarboxylic acid cycle and the pentose phosphate pathways of cancer cells.

Therapeutic Potential of Melatonin in the Regulation of MiR-148a-3p and Angiogenic Factors in Breast Cancer

BACKGROUND

The high mortality rate of breast cancer is related to the occurrence of metastasis, a process that is promoted by tumor angiogenesis. MicroRNAs are small molecules of noncoding mRNA that play a key role in gene regulation and are directly involved in the progression and angiogenesis of various tumor types, including breast cancer. Several miRNAs have been described as promoters or suppressors angiogenesis and may be associated with tumor growth and metastasis. Melatonin is an oncostatic agent with a capacity of modifying the expression of innumerable genes and miRNAs related to cancer.

OBJECTIVE

The aim of this study was to evaluate the role of melatonin and the tumor suppressor miR- 148a-3p on angiogenesis of breast cancer.

METHOD

MDA-MB-231 cells were treated with melatonin and modified with the overexpression of miR-148a-3p. The relative quantification in real-time of miR-148a-3p, IGF-IR and VEGF was performed by real-time PCR. The protein expression of these targets was performed by immunocytochemistry and immunohistochemistry. Survival, migration and invasion rates of tumor cells were evaluated. Finally, the xenograft model of breast cancer was performed to confirm the role of melatonin in the tumor.

RESULTS

The melatonin was able to increase the gene level of miR-148a-3p and decreased the gene and protein expression of IGF-1R and VEGF, both in vitro and in vivo. In addition, it also had an inhibitory effect on the survival, migration and invasion of breast tumor cells.

CONCLUSION

Our results confirm the role of melatonin in the regulation of miR-148a-3p and decrease of angiogenic factors.

Melatonin: An atypical hormone with major functions in the regulation of angiogenesis

Melatonin (N-acetyl-5-methoxytryptamine), a pleotropic molecule with a wide distribution, has received considerable attention in recent years, mostly because of its various major effects on tissues or cells since it has both receptor-dependent and receptor-independent actions over a wide range of concentrations. These biological and physiological functions of melatonin include regulation of circadian rhythms by modulating the expression of core oscillator genes, scavenging the reactive oxygen species and reactive nitrogen species, modulating the immune system and inflammatory response, and exerting cytoprotective and antiapoptotic effects. Given the multiple critical roles of melatonin, dysregulation of its production or any disruption in signaling through its receptors may have contributed in the development of a wide range of disorders including type 2 diabetes, aging, immune-mediated diseases, hypertension, and cancer. Herein, we focus on the modulatory effects of melatonin on angiogenesis and its implications as a therapeutic strategy in cancer and related diseases.

Evaluation of Interleukin 25 and Interleukin 25 Receptor Expression in Peripheral Blood Mononuclear Cells of Breast Cancer Patients and Normal Subjects

[Figure: see text] Interleukin 25 (IL-25) is a ligand for IL-25 receptor (IL-25R) with apoptotic effect on breast cancer epithelial cells that are produced by peripheral blood mononuclear cells (PBMCs). In this study, we aimed to evaluate IL-25/IL-25R mRNA expression in PBMCs, and also investigate correlation of IL-25/IL-25R with tumor stages/grades in patients with breast cancer. PBMCs and serum were isolated from 30 patients with breast cancer and 18 normal subjects. ELISA test was conducted for IL-25 cytokine. Total RNA was isolated from 2 × 10⁶ PBMCs and reverse transcribed to cDNA. Quantitative PCRs were performed for IL-25, IL-25R, and GAPDH genes. IL-25 mRNA expression in PBMCs of breast cancer patients (malignant and benign) was significantly lower than that in normal subjects, Also IL-25 expression in breast cancer patients with malignant tumor was significantly lower than that in nonmalignant patients. IL-25R expression in malignant patients was significantly higher than that of benign and normal subjects (P < 0.05). IL-25 in serum of normal subjects was higher than that of benign and malignant patients. There was a direct association between IL-25R expression and tumor grade/stage of cancer. In conclusion, IL-25 seems as a potential prognostic factor in the serum of breast cancer patients and reduction of IL-25 is associated with a higher grade/stage of cancer.

Melatonin is an appropriate candidate for breast cancer treatment: Based on known molecular mechanisms

Breast cancer is the most prevalent cancer and one of the most important causes of death in women throughout the world. Breast cancer risk factors include smoking, alcohol consumption, personal and family history, hypertension, and hormone therapy, long-term use of nonsteroidal anti-inflammatory drugs and tobacco usage. Surgery, chemotherapy, radiotherapy, immunotherapy, and neoadjuvant therapy are the current means for breast cancer treatment. Despite hormonal agents and chemotherapy, which have beneficial effects on lowering breast cancer death rate, the reaction of different people to these treatments is still a challenging point. Melatonin (N-acetyl-5-methoxy tryptamine) is a methoxy indole compound that is mainly secreted by the pineal gland at night; it is as an antioxidant, anti-inflammatory, and oncostatic agent. On the basis of recent studies, melatonin has antitumor properties on different cancer types and it may suppress cancer development in vitro and as well as in animal models. It is suggested that melatonin inhibits the development of breast cancer by various mechanisms. This paper summarizes the roles of melatonin in breast cancer treatment from the aspect of its molecular actions.

The emergence of melatonin in oncology: Focus on colorectal cancer

Within the last few decades, melatonin has increasingly emerged in clinical oncology as a naturally occurring bioactive molecule with substantial anticancer properties and a pharmacological profile optimal for joining the currently available pharmacopeia. In addition, extensive experimental data shows that this chronobiotic agent exerts oncostatic effects throughout all stages of tumor growth, from initial cell transformation to mitigation of malignant progression and metastasis; additionally, melatonin alleviates the side effects and improves the welfare of radio/chemotherapy-treated patients. Thus, the support of clinicians and oncologists for the use of melatonin in both the treatment and proactive prevention of cancer is gaining strength. Because of its epidemiological importance and symptomatic debut in advanced stages of difficult clinical management, colorectal cancer (CRC) is a preferential target for testing new therapies. In this regard, the development of effective forms of clinical intervention for the improvement of CRC outcome, specifically metastatic CRC, is urgent. At the same time, the need to reduce the costs of conventional anti-CRC therapy results is also imperative. In light of this status quo, the therapeutic potential of melatonin, and the direct and indirect critical processes of CRC malignancy it modulates, have aroused much interest. To illuminate the imminent future on CRC research, we focused our attention on the molecular mechanisms underlying the multiple oncostatic actions displayed by melatonin in the onset and evolution of CRC and summarized epidemiological evidence, as well as in vitro, in vivo and clinical findings that support the broadly protective potential demonstrated by melatonin.

Melatonin loaded with bacterial cellulose nanofiber by Pickering-emulsion solvent evaporation for enhanced dissolution and bioavailability

The objective of the present work aimed to explore the potential of bacterial cellulose (BC) for oral delivery of melatonin (MLT), a natural hormone that faces problems of low solubility and oral bioavailability. BC was hydrolyzed by sulfuric acid followed by the oxidation to prepare bacterial cellulose nanofiber suspension (BCNs). Melatonin-loaded bacterial cellulose nanofiber suspension (MLT-BCNs) was prepared by emulsion solvent evaporation method. The properties of freeze-dried BCs and MLT-BCNs were studied by Fluorescence microscopy (FM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermo gravimetric (TG). The results indicated that the fibers in BCNs became short and thin compared with BC, MLT in MLT-BCNs was uniformly distributed, both BCNs and MLT-BCNs have good thermodynamic stability. The MLT-BCNs showed more rapid dissolution MLT rates compared to the commercially available MLT in SGF and SIF, the dissolution of the cumulative release rate was about 2.1 times of the commercially available MLT. The oral bioavailability of MLT-BCNs in rat was about 2.4 times higher than the commercially available MLT. Thus, MLT-BCNs could act as promising delivery with enhanced dissolution and bioavailability for MLT after oral administration.

Evaluation of melatonin and AFMK levels in women with breast cancer

PURPOSE

Changes in the circadian rhythm may contribute to the development of cancer and are correlated with the high risk of breast cancer (BC) in night workers. Melatonin is a hormone synthesized by the pineal gland at night in the absence of light. Levels of melatonin and the metabolite of oxidative metabolism AFMK (acetyl-N-formyl-5-methoxykynurenamine), are suggested as potential biomarkers of BC risk. The aims of this study were to evaluate levels of melatonin and AFMK in women recently diagnosed with BC, women under adjuvant chemotherapy, and night-shift nurses, and compare them with healthy women to evaluate the relation of these compounds with BC risk.

METHODS

Blood samples were collected from 47 women with BC, 9 healthy women, 10 healthy night shift nurses, and 6 patients under adjuvant chemotherapy. Compound levels were measured by mass spectrometry.

RESULTS AND CONCLUSIONS

Our results showed that women with BC had lower levels of melatonin compared to control group women, and even lower in night-shift nurses and in patients under adjuvant chemotherapy. There was no significant difference of AFMK levels between the groups. In addition to this, high levels of melatonin and AFMK were related to patients with metastasis, and high levels of AFMK were related to the presence of lymph node-positive, tumor > 20 mm and patients who sleep with light at night. Our results showed a reduction of melatonin levels in BC patients, suggesting a relation with the disease, and in addition, point to the importance of melatonin supplementation in women that work at night to reduce the BC risk.

Mechanisms Underlying Tumor Suppressive Properties of Melatonin

There is considerable evidence that melatonin may be of use in the prevention and treatment of cancer. This manuscript will review some of the human, animal and cellular studies that provide evidence that melatonin has oncostatic properties. Confirmation that melatonin mitigates pathogenesis of cancer will be described from both direct study of its effects on carcinogenesis, and from indirect findings implicating disruption of the circadian cycle. A distinction is made between the role of melatonin in preventing the initiation of the tumorigenic pathway and the ability of melatonin to retard the progression of cancer. Melatonin appears to slow down the rate of advancement of established tumors and there is evidence that it constitutes a valuable complement to standard pharmacological and radiation treatment modalities. There are instances of the beneficial outcomes in cancer treatment which utilize a range of hormones and vitamins, melatonin being among the constituents of the mix. While these complex blends are empirically promising, they are only briefly mentioned here in view of the confounding influence of a multiplicity of agents studied simultaneously. The last section of this review examines the molecular mechanisms that potentially underlie the oncostatic effects of melatonin. Alterations in gene expression following activation of various transcription factors, are likely to be an important mediating event. These changes in gene activity not only relate to cancer but also to the aging process which underlies the onset of most tumors. In addition, epigenetic events such as modulation of histone acetylation and DNA methylation patterns throughout the lifespan of organisms need to be considered. The antioxidant and immunoregulatory roles of melatonin may also contribute to its cancer modulatory properties. Naturally, these mechanisms overlap and interact extensively. Nevertheless, in the interest of clarity and ease of reading, each is discussed as a separate topic section. The report ends with some general conclusions concerning the clinical value of melatonin which has been rather overlooked and understudied.

Melatonin restrains angiogenic factors in triple-negative breast cancer by targeting miR-152-3p: In vivo and in vitro studies

AIMS

Breast cancer represents the second most prevalent tumor-related cause of death among women. Although studies have already been published regarding the association between breast tumors and miRNAs, this field remains unclear. MicroRNAs (miRNAs) are defined as non-coding RNA molecules, and are known to be involved in cell pathways through the regulation of gene expression. Melatonin can regulate miRNAs and genes related with angiogenesis. This hormone is produced naturally by the pineal gland and presents several antitumor effects. The aim of this study was to understand the action of melatonin in the regulation of miRNA-152-3p in vivo and in vitro.

MAIN METHODS

In order to standardize the melatonin treatment in the MDA-MB-468 cells, we carried out the cell viability assay at different concentrations. PCR Array plates were used to identify the differentiated expression of miRNAs after the treatment with melatonin. The relative quantification of the target gene expression (IGF-IR, HIF-1α and VEGF) was performed by real-time PCR. For the tumor development, MDA-MB-468 cells were implanted in female BALB/c mice, and treated or not treated with melatonin. Moreover, the quantification of the target genes protein expression was performed by immunocytochemistry and immunohistochemistry.

KEY FINDINGS

Relative quantification shows that the melatonin treatment increases the gene expression of miR-152-3p and the target genes, and decreased protein levels of the genes both in vitro and in vivo.

SIGNIFICANCE

Our results confirm the action of melatonin on the miR-152-3p regulation known to be involved in the progression of breast cancer.