Allicin inhibits the invasion of lung adenocarcinoma cells by altering tissue inhibitor of metalloproteinase/matrix metalloproteinase balance via reducing the activity of phosphoinositide 3-kinase/AKT signaling

Plants as a Source of Anticancer Agents: From Bench to Bedside

Cancer is the second leading cause of death after cardiovascular diseases. Conventional anticancer therapies are associated with lack of selectivity and serious side effects. Cancer hallmarks are biological capabilities acquired by cancer cells during neoplastic transformation. Targeting multiple cancer hallmarks is a promising strategy to treat cancer. The diversity in chemical structure and the relatively low toxicity make plant-derived natural products a promising source for the development of new and more effective anticancer therapies that have the capacity to target multiple hallmarks in cancer. In this review, we discussed the anticancer activities of ten natural products extracted from plants. The majority of these products inhibit cancer by targeting multiple cancer hallmarks, and many of these chemicals have reached clinical applications. Studies discussed in this review provide a solid ground for researchers and physicians to design more effective combination anticancer therapies using plant-derived natural products.

Targeting Mutant Kirsten Rat Sarcoma Viral Oncogene Homolog in Non-Small Cell Lung Cancer: Current Difficulties, Integrative Treatments and Future Perspectives

In the past few decades, several gene mutations, including the anaplastic lymphoma kinase, epidermal growth factor receptor, ROS proto-oncogene 1 and rat sarcoma viral oncogene homolog (RAS), have been discovered in non-small cell lung cancer (NSCLC). Kirsten rat sarcoma viral oncogene homolog (KRAS) is the isoform most frequently altered in RAS-mutated NSCLC cases. Due to the structural and biochemical characteristics of the KRAS protein, effective approaches to treating KRAS-mutant NSCLC still remain elusive. Extensive recent research on KRAS-mutant inhibitors has made a breakthrough in identifying the covalent KRASG12C inhibitor as an effective agent for the treatment of NSCLC. This review mainly concentrated on introducing new covalent KRASG12C inhibitors like sotorasib (AMG 510) and adagrasib (MRTX 849); summarizing inhibitors targeting the KRAS-related upstream and downstream effectors in RAF/MEK/ERK pathway and PI3K/AKT/mTOR pathway; exploring the efficacy of immunotherapy and certain emerging immune-related therapeutics such as adoptive cell therapy and cancer vaccines. These inhibitors are being investigated in clinical trials and have exhibited promising effects. On the other hand, naturally extracted compounds, which have exhibited safe and effective properties in treating KRAS-mutant NSCLC through suppressing the MAPK and PI3K/AKT/mTOR signaling pathways, as well as through decreasing PD-L1 expression in preclinical studies, could be expected to enter into clinical studies. Finally, in order to confront the matter of drug resistance, the ongoing clinical trials in combination treatment strategies were summarized herein.

Evaluation of Allicin Against Alveolar Echinococcosis In Vitro and in a Mouse Model

Purpose

At present, the chemotherapy for alveolar echinococcosis (AE) is mainly based on albendazole (ABZ). However, more than 20% of patients fail chemotherapy. Therefore, new and more effective treatments are urgently needed. Allicin has been reported to have antibacterial and antiparasitic effects. The objectives of the present study were to investigate the in vivo and in vitro efficacy of allicin against Echinococcus multilocularis (E. multilocularis).

Methods

The effects of allicin on protoscolex survival and structural changes were evaluated in vitro. The 4-week-old BALB/c male mice used for in vivo modelling underwent inoculation of E. multilocularis protoscoleces by intraperitoneal injection, followed by intragastric administration of allicin for 6 weeks. Then, the effects of allicin on lymphocyte subsets, metacestode growth and host tissue matrix metalloproteinase 2 (MMP2)/MMP9 expression around metacestodes in mice were evaluated. The toxicity of allicin was further evaluated in vivo and in vitro.

Results

Att 40 μg/mL, allicin showed a killing effect on protoscoleces in vitro and treatment resulted in the destruction of protoscolex structure. Molecular docking showed that allicin could form hydrogen bonds with E. multilocularis cysteine enzymes. After 6 weeks of in vivo allicin treatment, the spleen index of mice was increased and the weight of metacestodes was reduced. Allicin increased the proportion of CD4⁺ T cells and decreased the proportion of CD8⁺ T cells in the peripheral blood and spleen. Pathological analysis of the metacestodes showed structural disruption of the germinal and laminated layers after allicin treatment. In addition, allicin inhibited the expression of MMP2 and MMP9 in metacestode-surrounding host tissues. At 160 μg/mL, allicin had no significant toxicity to normal hepatocytes but could inhibit hepatoma cell proliferation. At 30 mg/kg, allicin had no significant hepatorenal toxicity in vivo.

Conclusion

These results suggest that allicin exerts anti-E. multilocularis effects in vitro and in vivo and can enhance immune function in mice, with the potential to be developed as a lead compound against echinococcosis.

Re-establishing the comprehension of phytomedicine and nanomedicine in inflammation-mediated cancer signaling

Recent mounting evidence has revealed extensive genetic heterogeneity within tumors that drive phenotypic variation affecting key cancer pathways, making cancer treatment extremely challenging. Diverse cancer types display resistance to treatment and show patterns of relapse following therapy. Therefore, efforts are required to address tumor heterogeneity by developing a broad-spectrum therapeutic approach that combines targeted therapies. Inflammation has been progressively documented as a vital factor in tumor advancement and has consequences in epigenetic variations that support tumor instigation, encouraging all the tumorigenesis phases. Increased DNA damage, disrupted DNA repair mechanisms, cellular proliferation, apoptosis, angiogenesis, and its incursion are a few pro-cancerous outcomes of chronic inflammation. A clear understanding of the cellular and molecular signaling mechanisms of tumor-endorsing inflammation is necessary for further expansion of anti-cancer therapeutics targeting the crosstalk between tumor development and inflammatory processes. Multiple inflammatory signaling pathways, such as the NF-κB signaling pathway, JAK-STAT signaling pathway, MAPK signaling, PI3K/AKT/mTOR signaling, Wnt signaling cascade, and TGF-β/Smad signaling, have been found to regulate inflammation, which can be modulated using various factors such as small molecule inhibitors, phytochemicals, recombinant cytokines, and nanoparticles in conjugation to phytochemicals to treat cancer. Researchers have identified multiple targets to specifically alter inflammation in cancer therapy to restrict malignant progression and improve the efficacy of cancer therapy. siRNA-and shRNA-loaded nanoparticles have been observed to downregulate STAT3 signaling pathways and have been employed in studies to target tumor malignancies. This review highlights the pathways involved in the interaction between tumor advancement and inflammatory progression, along with the novel approaches of nanotechnology-based drug delivery systems currently used to target inflammatory signaling pathways to combat cancer.

Chemical diversity of dietary phytochemicals and their mode of chemoprevention

Despite the advancement in prognosis, diagnosis and treatment, cancer has emerged as the second leading cause of disease-associated death across the globe. With the remarkable application of synthetic drugs in cancer therapy and the onset of therapy-associated adverse effects, dietary phytochemicals have been materialized as potent anti-cancer drugs owing to their antioxidant, apoptosis and autophagy modulating activities. With dynamic regulation of apoptosis and autophagy in association with cell cycle regulation, inhibition in cellular proliferation, invasion and migration, dietary phytochemicals have emerged as potent anti-cancer pharmacophores. Dietary phytochemicals or their synthetic analogous as individual drug candidates or in combination with FDA approved chemotherapeutic drugs have exhibited potent anti-cancer efficacy. With the advancement in cancer therapeutics, dietary phytochemicals hold high prevalence for their use as precision and personalized medicine to replace conventional chemotherapeutic drugs. Hence, keeping these perspectives in mind, this review focuses on the diversity of dietary phytochemicals and their molecular mechanism of action in several cancer subtypes and tumor entities. Understanding the possible molecular key players involved, the use of dietary phytochemicals will thrive a new horizon in cancer therapy.

Modulation of Matrix Metalloproteinases by Plant-derived Products

Matrix metalloproteinases (MMPs) are a group of zinc-dependent metalloendopeptidases that are responsible for the degradation, repair, and remodeling of extracellular matrix components. MMPs play an important role in maintaining a normal physiological function and preventing diseases, such as cancer and cardiovascular diseases. Natural products derived from plants have been used as traditional medicine for centuries. Its active compounds, such as catechin, resveratrol and quercetin, are suggested to play an important role as MMPs inhibitors, thereby opening new insights into their applications in many fields, such as pharmaceutical, cosmetic, and food industries. This review summarises the current knowledge of plant-derived natural products with MMP-modulating activities. Most of the reviewed plant-derived products exhibit an inhibitory activity on MMPs. Amongst MMPs, MMP-2 and MMP-9 are the most studied. The expression of MMPs is inhibited through respective signaling pathways, such as MAPK, NF-κB and PI3 kinase pathways, which contribute to the reduction in cancer cell behaviors, such as proliferation and migration. Most studies have employed in vitro models, but a limited number of animal studies and clinical trials have been conducted. Even though plant-derived products show promising results in modulating MMPs, more in vivo studies and clinical trials are needed to support their therapeutic applications in the future.

The in Vitro Antischistosomal Activity and Genotoxicity of the Active Ingredients of Allium sativum (allicin) and Curcuma longa (curcumin)

Background:

In this study, we assessed the in vitro antischistosomal activity of the active ingredients of Allium sativum (allicin) and Curcuma longa (curcumin) on Schistosoma mansoni.

Methods:

This study was conducted in Faculty of Science, Port said University, Egypt (2018). Adult worms were exposed to a range of concentrations of AL or CU, and worm survival was assessed 24 h post-exposure to calculate the lethal concentration of the compounds. Scanning electron microscopy was used to assess ultrastructural changes in the surface of AL- or CU- treated worms. The genotoxicities of AL and CU on S. mansoni were determined by DNA fragmentation analysis.

Results:

We determined the concentrations of AL and CU required to kill 50% of S. mansoni (LC₅₀ ). The LC₅₀ of AL was 8.66 μL/mL, whereas 100% mortality of S. mansoni was achieved by AL at concentrations of 50 μL/mL. The LC₅₀ of CU was 87.25 μL/mL, with the highest mortality of 91.3% seen after 24 h exposure to 100 μg/mL CU. Ultrastructural studies revealed that exposure to either AL or CU led to mild or severe surface damage to S. mansion, respectively. The degree of damage in the worms was sex-dependent. Interestingly, while CU exposure resulted in DNA fragmentation in S. mansoni worms, we observed no genotoxic effects of AL.

Conclusion:

Both AL and CU exhibit antischistosomal activity; the study provided evidence suggesting that these compounds act through distinct mechanisms. These promising results encourage further investigation into these compounds as potential antischistosomal agents, either alone or as complementary treatments to praziquantel.

Phytochemical Analysis and In Vitro Effects of Allium fistulosum L. and Allium sativum L. Extracts on Human Normal and Tumor Cell Lines: A Comparative Study

Allium sativum L. (garlic bulbs) and Allium fistulosum L. (Welsh onion leaves) showed quantitative differences of identified compounds: allicin and alliin (380 µg/mL and 1410 µg/mL in garlic; 20 µg/mL and 145 µg/mL in Welsh onion), and the phenolic compounds (chlorogenic acid, p-coumaric acid, ferulic acid, gentisic acid, 4-hydroxybenzoic acid, kaempferol, isoquercitrin, quercitrin, quercetin, and rutin). The chemical composition determined the inhibitory activity of Allium extracts in a dose-dependent manner, on human normal cells (BJ-IC50 0.8841% garlic/0.2433% Welsh onion and HaCaT-IC50 1.086% garlic/0.6197% Welsh onion) and tumor cells (DLD-1-IC50 5.482%/2.124%; MDA-MB-231-IC50 6.375%/2.464%; MCF-7-IC50 6.131%/3.353%; and SK-MES-1-IC50 4.651%/5.819%). At high concentrations, the cytotoxic activity of each extract, on normal cells, was confirmed by: the 50% of the growth inhibition concentration (IC50) value, the cell death induced by necrosis, and biochemical determination of LDH, catalase, and Caspase-3. The four tumor cell lines treated with high concentrations (10%, 5%, 2.5%, and 1.25%) of garlic extract showed different sensibility, appreciated on the base of IC50 value for the most sensitive cell line (SK-MES-1), and the less sensitive (MDA-MB-231) cell line. The high concentrations of Welsh onion extract (5%, 2.5%, and 1.25%) induced pH changes in the culture medium and SK-MES-1 being the less sensitive cell line.

Antileukemic activity of sulfoxide nutraceutical allicin against THP-1 cells is associated with premature phosphatidylserine exposure in human erythrocytes

Background

Allicin (ACN), a sulfoxide in freshly crushed garlic, is known for its diverse bioactive properties. Among the most notable effects of ACN is its antitumor activity against a wide array of cancer types. Thus, ACN may be a promising anticancer therapeutic. Nevertheless, chemotherapy-induced anemia is a major obstacle in cancer management with a prevalence of up to 70%. Although the pathophysiology behind it remains elusive, a number of medications known to cause anemia in patients have been shown to induce premature programmed cell death in red blood cells (RBCs) known as eryptosis. This study, thus, investigates the anticancer potential of ACN against THP-1 monocytic leukemia cells, its toxic effects on human RBCs, and delineate the underlying biochemical mechanisms.

Methods

Cytotoxicity was detected using the MTT assay, while hemoglobin leakage was used as a surrogate for hemolysis which was photometrically measured. Major eryptotic events were examined using flow cytometry with fluorescent probes. Phosphatidylserine (PS) exposure was detected by Annexin-V-FITC, cytosolic calcium with Fluo4/AM, and reactive oxygen species with H₂DCFDA.

Results

Our results show that ACN induces hemolysis in a dose-dependent fashion, which is significantly abrogated in absence of extracellular calcium. Moreover, ACN stimulates PS exposure, intracellular calcium overload, and oxidative stress. Using small-molecule inhibitors, we demonstrate that the pro-eryptotic activity of ACN is ameliorated in presence of zVAD(OMe)-FMK, SB203580, and D4476.

Conclusion

ACN possesses both hemolytic and eryptotic properties mediated through elevated intracellular calcium levels, oxidative stress, caspase, p38 MAPK, and CK1α.

Allicin suppresses growth and metastasis of gastric carcinoma: the key role of microRNA-383-5p-mediated inhibition of ERBB4 signaling

Allicin is a natural product suppressing the progression of gastric carcinoma (GC). In the current study, the mechanism underlying the anti-GC effect of allicin was explored by focusing on the role of miR-383-5p/ERBB4 signaling. Two GC cell lines were treated with allicin and the effects on viability, apoptosis, migration, invasion, and miR-383-5p/ERBB4 activity in the cells were assessed. The interaction between allicin and miR-383-5p was further explored by inhibiting the miR-383-5p level. Allicin suppressed cell viability and induced apoptosis in both GC cell lines. The compound also inhibited migration and invasion of GC cells, which was associated with the up-regulation miR-383-5p and down-regulation of ERBB4. The inhibition of miR-383-5p by specific inhibitor blocked the anti-GC effect of allicin. Our results demonstrated that allicin contributed to the suppressed growth and metastasis potentials in GC cell lines. The effect was accompanied by an increased level of miR-383-5p and subsequent inhibition of ERBB4.

The Synergistic Antitumor Effect of 5-Fluorouracil Combined with Allicin against Lung and Colorectal Carcinoma Cells

5-fluorouracil (5-FU) is an anticancer drug used to inhibit the proliferation of many different tumor cells. Since severe events are associated with this compound, its combination with different anticancer drugs or adjuvants would allow the use of a significantly lower dose of 5-FU. In this study, we highlighted that the combination of allicin with 5-FU inhibited the cell migration and proliferation of colorectal and lung cancer cells. 5-FU inhibited cell growth with a similar inhibitory concentration for both normal and tumor cells (~200µM), while allicin showed different inhibitory concentrations. With an IC50 of 8.625 µM, lung cancer cells were the most sensitive to allicin. Compared to 5-FU and allicin single-agent treatments, the co-treatment showed a reduced viability rate, with p < 0.05. The morphological changes were visible on all three cell lines, indicating that the treatment inhibited the proliferation of both normal and tumor cells. We highlighted different cell death mechanisms—apoptosis for lung cancer and a non-apoptotic cell death for colorectal cancer. The synergistic antitumor effect of 5-FU combined with allicin was visible against lung and colorectal carcinoma cells. Better results were obtained when a lower concentration of 5-FU was combined with allicin than the single-agent treatment at IC50.

Garlic and its Active Compounds: A Potential Candidate in The Prevention of Cancer by Modulating Various Cell Signalling Pathways

BACKGROUND

Cancer is a multi-factorial disease including alterations in the cell signalling pathways. Currently, several drugs are in use to treat cancer but such drugs show negative side effects on normal cells and cause severe toxicity.

METHODS

The current research is mainly focused on medicinal plants with potential therapeutic efficacy in the treatment of cancer without any adverse effects on normal cells. In this regard, garlic and its active compounds including diallyl sulfide, diallyl trisulfide, ajoene, and allicin have been established to suppress the growth of cancer and killing of cancer cells.

RESULT

The review focuses on garlic and its active compounds chemopreventive effect through modulating various cell signalling pathways. Additionally, garlic and its active compound were established to induce cell cycle arrest at the G0/G1 phase and G2/M phases in cancer cells, increase the expression of tumor suppressor genes, inhibit the angiogenesis process, induction of apoptosis and modulation of various other genetic pathways.

CONCLUSION

This review sketches the diverse chemopreventive activities of garlic and their active ingredients in the management of cancer mainly focusing on cell signalling pathways.

Phytochemicals in Cancer Treatment: From Preclinical Studies to Clinical Practice

Cancer is a severe health problem that continues to be a leading cause of death worldwide. Increasing knowledge of the molecular mechanisms underlying cancer progression has led to the development of a vast number of anticancer drugs. However, the use of chemically synthesized drugs has not significantly improved the overall survival rate over the past few decades. As a result, new strategies and novel chemoprevention agents are needed to complement current cancer therapies to improve efficiency. Naturally occurring compounds from plants known as phytochemicals, serve as vital resources for novel drugs and are also sources for cancer therapy. Some typical examples include taxol analogs, vinca alkaloids such as vincristine, vinblastine, and podophyllotoxin analogs. These phytochemicals often act via regulating molecular pathways which are implicated in growth and progression of cancer. The specific mechanisms include increasing antioxidant status, carcinogen inactivation, inhibiting proliferation, induction of cell cycle arrest and apoptosis; and regulation of the immune system. The primary objective of this review is to describe what we know to date of the active compounds in the natural products, along with their pharmacologic action and molecular or specific targets. Recent trends and gaps in phytochemical based anticancer drug discovery are also explored. The authors wish to expand the phytochemical research area not only for their scientific soundness but also for their potential druggability. Hence, the emphasis is given to information about anticancer phytochemicals which are evaluated at preclinical and clinical level.

Recent progress in natural dietary non-phenolic bioactives on cancers metastasis

From several decades ago to now, cancer continues to be the leading cause of death worldwide, and metastasis is the major cause of cancer-related deaths. For health benefits, there is a great desire to use non-chemical therapy such as nutraceutical supplementation to prevent pathology development. Over 10,000 different natural bioactives or phytochemicals have been known that possessing potential preventive or supplementary effects for various diseases including cancer. Previously, the in vitro and in vivo anti-invasive and anti-metastatic activities of phenolic acids, monophenol, polyphenol and their derivatives and flavonoids and their derivatives have been reviewed. However, a vast number of natural dietary compounds other than phenolics have been demonstrated to potentially possess the ability to inhibit the invasion and metastasis of various cancers. In this review, we summarize the studies in recent decade on in vitro and in vivo effects and molecular mechanisms of natural bioactives, excluding the phenolics in food, in cancer invasion and metastasis. By combining this review of non-phenolics with the previous phenolics reviews, the puzzle for the contribution of natural dietary bioactives on cancer invasive or/and metastatic progress will be almost complete and more clear.

Downregulating PI3K/Akt/NF-κB signaling with allicin for ameliorating the progression of osteoarthritis:in vitroandvivostudies

A schematic illustration of the potential protective effects of allicin on osteoarthritis development.