EGFR gene regulation in colorectal cancer cells by garlic phytocompounds with special emphasis on S-Allyl-L-Cysteine Sulfoxide

Evidence-based capacity of natural cytochrome enzyme inhibitors to increase the effectivity of antineoplastic drugs

Cytochrome (CYP) enzymes catalyze the metabolism of numerous exogenous and endogenous substrates in cancer therapy leading to significant drug interactions due to their metabolizing effect. CYP enzymes play an important role in the metabolism of essential anticancer medications. They are shown to be overexpressed in tumor cells at numerous locations in the body. This overexpression could be a result of lifestyle factors, presence of hereditary variants of CYP (Bio individuality) and multi-drug resistance. This finding has sparked an interest in using CYP inhibitors to lower their metabolizing activity as a result facilitating anti-cancer medications to have a therapeutic impact. As a result of the cytotoxic nature of synthetic enzyme inhibitors and the increased prevalence of herbal medication, natural CYP inhibitors have been identified as an excellent way to inhibit overexpression sighting their tendency to show less cytotoxicity, lesser adverse drug reactions and enhanced bioavailability. Nonetheless, their effect of lowering the hindrance caused in chemotherapy due to CYP enzymes remains unexploited to its fullest. It has been observed that there is a substantial decrease in first pass metabolism and increase in intestinal absorption of chemotherapeutic drugs like paclitaxel when administered along with flavonoids which help suppress certain specific cytochrome enzymes which play a role in paclitaxel metabolism. This review elaborates on the role and scope of phytochemicals in primary, secondary and tertiary care and how targeted prevention of cancer could be a breakthrough in the field of chemotherapy and oncology. This opens up a whole new area of research for delivery of these natural inhibitors along with anticancer drugs with the help of liposomes, micelles, nanoparticles, the usage of liquid biopsy analysis, artificial intelligence in medicine, risk assessment tools, multi-omics and multi-parametric analysis. Further, the site of action, mechanisms, metabolites involved, experimental models, doses and observations of two natural compounds, quercetin & thymoquinone, and two plant extracts, liquorice & garlic on CYP enzymes have been summarized.

New combination of drugs to combat Escherichia coli DSM1103 QCDSM by reducing antibiotic ciprofloxacin standard dose using response surface methodology

BACKGROUND

Microbial diseases are emerged as a concern for the global health and are responsible for increased mortality among different age groups. It is therefore essential to control the microbial population with novel antimicrobial agents. Antibiotic-phytochemicals mixtures are used for improving the antibacterial efficiency against bacterial pathogens to decrease their microbial resistance development. This study compared the inhibitory potentials of ciprofloxacin antibiotic and phytochemical mixtures of Syzygium aromaticum (clove), Allium sativum (garlic) and Cinnamomum verum (cinnamon) against Escherichia coli DSM1103 QCDSM using Minimal inhibitory concentrations (MICs) and Bactericidal inhibitory concentrations (MBCs) methods.

OBJECTIVE

Inhibitory activity of ciprofloxacin and three oil plant extracts of the selected plants (clove, garlic, cinnamon) were tested against E. coli DSM1103 QCDSM using well diffusion method on Muller-Hinton agar plates by studying MIC and MBC tests. The software "Design Expert® 12" Stat-Ease was used to analyze the experimental mixture design.

RESULTS

A mixture design of twenty mixture combination runs using different concentration levels of ciprofloxacin and the three oil plants extracts were performed against E. coli DSM1103 QCDSM growth. Results revealed that the standard recommended ciprofloxacin dose 5 μg/100 ml may be replaced by the oil extracts of S. aromaticum 4.75 % (v/v), A. sativum 5.0% (v/v), C. verum 5.0%(v/v) and ciprofloxacin 0.25% (w/v) as alternative drugs.

CONCLUSION

The proposed mixture containing Syzygium aromaticum (clove), Allium sativum (garlic) and Cinnamomum verum (cinnamon) was found to be an effective antimicrobial agent and may signifies the role of traditional knowledge in drug discovery.

Phytochemical profiling of Azima tetracantha Lam. leaf methanol extract and elucidation of its potential as a chain-breaking antioxidant, anti-inflammatory and anti-proliferative agent

Azima tetracantha, a traditional medicinal plant included in the order Brassicales and family Salvadoraceae, is widely used as a dietary supplement in folklore medicines. The plant is also used for the treatment of rheumatism, diarrhea and other inflammatory disorders. The present investigation focused on the phytochemical composition, radical scavenging, reducing potential and anti-proliferative activities of the A. tetracantha leaves. Quantitative estimation of the polyphenols and flavonoids revealed significantly elevated levels in the methanol extract. Corroborating with this, methanol extract exhibited higher in vitro anti-radical scavenging effect against 2,2-diphenyl-1- picrylhydrazyl (34.14 ± 2.19 μg/mL), and hydrogen peroxide (44.96 ± 1.77 μg/mL), as well as ferric reducing properties (58.24 ± 6.98 μg/mL). The methanolic extract also showed strong lipoxygenase (71.42 ± 6.36 μg/mL) and nitric oxide inhibitory activities (94.23 ± 8.11 μg/mL). Cytotoxic activity against MCF7 cells was found to be higher (IC50= 37.62 ± 2.94 μg/mL), than that of MDAMB231 cells (IC50= 69.11 ± 5.02 μg/mL). The qPCR-based analysis indicated dose-dependent increase in the expression of the pro-apoptotic genes such as executioner caspases and apoptotic protease activating factor-1. Overall, the results indicated the possible use of methanol extract of A. tetracantha leaves as a chain-breaking antioxidant molecule and are capable of inhibiting inflammatory enzymes and the proliferative potential of breast cancer cells.

Phytochemicals as PI3K/ Akt/ mTOR Inhibitors and Their Role in Breast Cancer Treatment

BACKGROUND

Breast cancer is the predominant form of cancer in women; various cellular pathways are involved in the initiation and progression of breast cancer. Among the various types of breast cancer that differ in their growth factor receptor status, PI3K/Akt signaling is a common pathway where all these converge. Thus, the PI3K signaling is of great interest as a target for breast cancer prevention; however, it is less explored.

OBJECTIVE

The present review is aimed to provide a concise outline of the role of PI3K/Akt/mTOR pathway in breast carcinogenesis and its progression events, including metastasis, drug resistance and stemness. The review emphasizes the role of natural and synthetic inhibitors of PI3K/Akt/m- TOR pathway in breast cancer prevention.

METHODS

The data were obtained from PubMed/Medline databases, Scopus and Google patent literature.

RESULTS

PI3K/Akt/mTOR signaling plays an important role in human breast carcinogenesis; it acts on the initiation and progression events associated with it. Numerous molecules have been isolated and identified as promising drug candidates by targeting the signaling pathway. Results from clinical studies confirm their application in the treatment of human breast cancer alone and in combination with classical chemotherapeutics as well as monoclonal antibodies.

CONCLUSION

PI3K/mTOR signaling blockers have evolved as promising anticancer agents by interfering breast cancer development and progression at various stages. Natural products and bioactive components are emerging as novel inhibitors of PI3K signaling and more research in this area may yield numerous drug candidates.

The Potential Application of Allium Extracts in the Treatment of Gastrointestinal Cancers

Herbal medicine is currently widely practiced, since natural resources are reported to alleviate side effects during oncological treatment while modifying cancer cell responses at the same time. Allium vegetables and their constituents have recently been extensively investigated due to the numerous possible beneficial properties, establishing them as an additional treatment modality in different cancers. According to the epidemiological evidence, as well as many in vivo and in vitro studies, the abovementioned substances seem to be effective in the prevention and inhibition of the progression of carcinogenesis. Due to high concentrations of organosulfur compounds, which exhibit anticarcinogenic, antimicrobial, as well as anti-inflammatory properties, Allium constituents are believed to constitute a promising prevention and supportive therapy for oncological patients. Besides, it was demonstrated that a combination of Allium extracts with chemotherapy provided satisfactory clinical outcomes while at the same time being cost-effective. The aim of this review was to present and discuss currently investigated Allium extracts and their effects on several gastrointestinal cancers including gastric, colon, liver, esophageal, and pancreatic cancer.

Targeting Toll like Receptors in Cancer: Role of TLR Natural and Synthetic Modulators

Background:

Toll like receptors (TLRs) are a group of transmembrane receptors belonging to the broad class pattern recognition receptors (PRR), involved in recognition of Pathogen Associated Molecular Patterns (PAMPs) thereby inducing an immune response. Apart from these exogenous PAMPs, numerous endogenous PAMPs are also ligands for various TLRs thereby activating the TLR dependent immune response, subsequently leading to the onset of an inflammatory response. Prolonged activation of TLR by these endogenous PAMPs leads to chronic inflammatory insults to the body and which in turn alters the proliferative patterns of the cells, which ultimately leads to the development of cancer.

Objectives:

The present review aims to provide a detailed outline of the differential roles of various TLRs in cancer and the possible use of them as a therapeutic target.

Methods:

Data were collected from PubMed/Sciencedirect/Web of Science database and sorted; the latest literature on TLRs was incorporated in the review.

Results:

Among the different TLRs, few are reported to be anti-neoplastic, which controls the cell growth and multiplication in response to the endogenous signals. On the contrary, numerous studies have reported the procarcinogenic potentials of TLRs. Hence, TLRs have emerged as a potential target for the prevention and treatment of various types of cancers. Several molecules, such as monoclonal antibodies, small molecule inhibitors and natural products have shown promising anticancer potential by effectively modulating the TLR signalling.

Conclusion:

Toll-like receptors play vital roles in the process of carcinogenesis, hence TLR targeting is a promising approach for cancer prevention.

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.

Glutathione, an Antioxidant Tripeptide: Dual Roles in Carcinogenesis and Chemoprevention

Glutathione (GSH or reduced glutathione) is a tripeptide of gamma-Glutamyl-cysteinylglycine and the predominant intracellular antioxidant in many organisms including humans. GSH and associated enzymes are controlled by a transcription factor-nuclear factor-2 related erythroid factor-2 (Nrf2). In cellular milieu, GSH protects the cells essentially against a wide variety of free radicals including reactive oxygen species, lipid hydroperoxides, xenobiotic toxicants, and heavy metals. It has two forms, the reduced form or reduced glutathione (GSH) and oxidized form (GSSG), where two GSH moieties combine by sulfhydryl bonds. Glutathione peroxidase (GPx) and glutathione-s-transferase (GST) essentially perform the detoxification reactions using GSH, converting it into GSSG. Glutathione reductase (GR) operates the salvage pathway by converting GSSG to GSH with the expense of NADPH and restores the cellular GSH pool. Hence, GSH and GSH-dependent enzymes are necessary for maintaining the normal redox balance in the body and help in cell survival under stress conditions. In addition, GST removes various carcinogenic compounds offering a chemopreventive property, whereas the GSH system plays a significant role in regulating the cellular survival by offering redox stability in a variety of cancers including prostate, lung, breast, and colon cancer. Studies have also indicated that GSH inhibitors, such as buthionine sulfoximine, improve the chemo-sensitivity in cancer cells. In addition, GSH and dependent enzymes provide a survival advantage for cancer cells against chemotherapeutic drugs and radiotherapy.

Phytochemicals and Gastrointestinal Cancer: Cellular Mechanisms and Effects to Change Cancer Progression

Gastrointestinal (GI) cancer is a prevailing global health disease with a high incidence rate which varies by region. It is a huge economic burden on health care providers. GI cancer affects different organs in the body such as the gastric organs, colon, esophagus, intestine, and pancreas. Internal and external factors like smoking, obesity, urbanization, genetic mutations, and prevalence of Helicobacter pylori and Hepatitis B and Hepatitis C viral infections could increase the risk of GI cancer. Phytochemicals are non-nutritive bioactive secondary compounds abundantly found in fruits, grains, and vegetables. Consumption of phytochemicals may protect against chronic diseases like cardiovascular disease, neurodegenerative disease, and cancer. Multiple studies have assessed the chemoprotective effect of selected phytochemicals in GI cancer, offering support to their potential towards reducing the pathogenesis of the disease. The aim of this review was to summarize the current knowledge addressing the anti-cancerous effects of selected dietary phytochemicals on GI cancer and their molecular activities on selected mechanisms, i.e., nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), detoxification enzymes, adenosine monophosphate activated protein kinase (AMPK), wingless-related integration site/β-catenin (wingless-related integration site (Wnt) β-catenin, cell apoptosis, phosphoinositide 3-kinases (PI3K)/ protein kinase B AKT/ mammalian target of rapamycin (mTOR), and mitogen-activated protein kinase (MAPK). In this review phytochemicals were classified into four main categories: (i) carotenoids, including lutein, lycopene, and β-carotene; (ii) proanthocyanidins, including quercetin and ellagic acid; (iii) organosulfur compounds, including allicin, allyl propyl disulphide, asparagusic acid, and sulforaphane; and (iv) other phytochemicals including pectin, curcumins, p-coumaric acid and ferulic acid. Overall, phytochemicals improve cancer prognosis through the downregulation of β-catenin phosphorylation, therefore enhancing apoptosis, and upregulation of the AMPK pathway, which supports cellular homeostasis. Nevertheless, more studies are needed to provide a better understanding of the mechanism of cancer treatment using phytochemicals and possible side effects associated with this approach.

Heat Shock Proteins (HSPs): A Novel Target for Cancer Metastasis Prevention

Background:

Heat shock proteins (HSPs) are predominant molecular chaperones which are actively involved in the protein folding; which is essential in protecting the structure and functioning of proteins during various stress conditions. Though HSPs have important physiological roles, they have been well known for their roles in various pathogenic conditions such as carcinogenesis; however, limited literature has consolidated its potential as an anti-metastatic drug target.

Objectives:

The present review outlines the role of different HSPs on cancer progression and metastasis; possible role of HSP inhibitors as anti-neoplastic agents is also discussed.

Methods:

The data were collected from PubMed/Medline and other reputed journal databases. The literature that was too old and had no significant role to the review was then omitted.

Results:

Despite their strong physiological functions, HSPs are considered as good markers for cancer prognosis and diagnosis. They have control over survival, proliferation and progression events of cancer including drug resistance, metastasis, and angiogenesis. Since, neoplastic cells are more dependent on HSPs for survival and proliferation, the selectivity and specificity of HSP-targeted cancer drugs remain high. This has made various HSPs potential clinical and experimental targets for cancer prevention. An array of HSP inhibitors has been in trials and many others are in experimental conditions as anticancer and anti-metastatic agents. Several natural products are also being investigated for their efficacy for anticancer and anti-metastatic agents by modulating HSPs.

Conclusion:

Apart from their role as an anticancer drug target, HSPs have shown to be promising targets for the prevention of cancer progression. Extensive studies are required for the use of these molecules as anti-metastatic agents. Further studies in this line may yield specific and effective antimetastatic agents.

Lauric acid induce cell death in colon cancer cells mediated by the epidermal growth factor receptor downregulation: An in silico and in vitro study

Coconut oil (CO) is enriched with medium chain saturated fatty acids like lauric acid (LA), capric acid and caprylic acid, which are known to have several health benefits. LA, the predominant fatty acid in CO, is reported to possess anticancer activity mediated through oxidative stress-induced apoptosis; however, there is no clear information on its cellular signalling mechanism. The present study screened the anticancer potential of various fatty acids present in CO (capric acid, caprylic acid and LA) using in silico tools such as CDOCKER in Accelrys Discovery Studio by targeting proteins like epidermal growth factor receptor (EGFR), cyclin-dependent kinase and thymidine synthase (TS). The results were further confirmed using cell culture-based studies and quantitative PCR. Among the tested compounds, LA was found to be the most active and showed a higher affinity towards EGFR and TS. Corroborating with these results, LA-induced dose-dependent cytotoxicity towards HCT-15 (human colon cancer), HepG2 (human hepatocellular carcinoma) and Raw 264.7 (murine macrophages) cells exhibiting morphological characteristics of apoptosis. Further, in HCT-15 cells exposed to LA (30 and 50 µg/mL), the expression of EGFR was found to be downregulated by 1.33- and 1.58-fold. The study thus concludes that the anticancer activity of LA may be partially mediated by the downregulation of EGFR signalling and consequent reduction in cell viability through apoptosis. Since EGFR signalling is crucial in cancer cell survival and is a prime target in drug development, the present study has pharmacological significance.

A Fluorescent Coumarin-Based Probe for the Fast Detection of Cysteine with Live Cell Application

A new coumarin-based fluorescent probe, containing an allylic esters group, has been designed and synthesized for sensing cysteine in physiological pH. In this fluorescent probe, the coumarin was applied as the fluorophore and an allylic esters group was combined as both a fluorescence quencher and a recognition unit. The probe can selectively and sensitively detect cysteine (Cys) over homocysteine, glutathione, and other amino acids, and has a rapid response time of 30 min and a low detection limit of 47.7 nM. In addition, the probe could be applied for cell imaging with low cytotoxicity.