Targeting kinases with thymoquinone: a molecular approach to cancer therapeutics

Paraoxonase-1: How a xenobiotic detoxifying enzyme has become an actor in the pathophysiology of infectious diseases and cancer

Both infectious and non-infectious diseases can share common molecular mechanisms, including oxidative stress and inflammation. External factors, such as bacterial or viral infections, excessive calorie intake, inadequate nutrients, or environmental factors, can cause metabolic disorders, resulting in an imbalance between free radical production and natural antioxidant systems. These factors may lead to the production of free radicals that can oxidize lipids, proteins, and nucleic acids, causing metabolic alterations that influence the pathogenesis of the disease. The relationship between oxidation and inflammation is crucial, as they both contribute to the development of cellular pathology. Paraoxonase 1 (PON1) is a vital enzyme in regulating these processes. PON1 is an enzyme that is bound to high-density lipoproteins and protects the organism against oxidative stress and toxic substances. It breaks down lipid peroxides in lipoproteins and cells, enhances the protection of high-density lipoproteins against different infectious agents, and is a critical component of the innate immune system. Impaired PON1 function can affect cellular homeostasis pathways and cause metabolically driven chronic inflammatory states. Therefore, understanding these relationships can help to improve treatments and identify new therapeutic targets. This review also examines the advantages and disadvantages of measuring serum PON1 levels in clinical settings, providing insight into the potential clinical use of this enzyme.

Cordycepin and kinase inhibition in cancer

Cordycepin, a nucleoside from Cordyceps mushrooms, has many beneficial properties for health, including anticancer activities. In cancer cells, cordycepin targets various signaling molecules. Here, we review the possible anticancer mechanisms of cordycepin involving the targeting of kinases. Abnormal kinase expression is involved in cancer development and progression through different molecular mechanisms, including phosphorylation, amplification, genetic mutations, and epigenetic regulation. Research suggests that kinases, such as the c-Jun N-terminal kinase (JNK), mitogen-activated protein kinase (MAPK), AMP kinase (AMPK), phosphoinositide 3-kinase (PI3K)/Akt, extracellular signal-regulated kinase (ERK), mammalian target of rapamycin (mTOR), glycogen synthase kinase (GSK)-3β, and focal adhesion kinase (FAK) pathways, can be targeted by cordycepin and disrupting their activity. Given that kinase inhibitors can have crucial roles in cancer treatment, targeting kinases might be one of the molecular mechanisms involved in the anticancer potential of cordycepin.

Gold Nanoparticles in Triple-Negative Breast Cancer Therapeutics

BACKGROUND

Triple-negative breast cancer (TNBC) is the most aggressive type of breast cancer with enhanced metastasis and poor survival. Though chemotherapy, radiotherapy, photothermal therapy (PTT), photodynamic therapy (PDT), and gene delivery are used to treat TNBC, various side effects limit these therapeutics against TNBC. In this review article, we have focused on the mechanism of action of gold nanoparticles (AuNPs) to enhance the efficacy of therapeutics with targeted delivery on TNBC cells.

METHODS

Research data were accumulated from PubMed, Scopus, Web of Science, and Google Scholar using searching criteria "gold nanoparticles and triple-negative breast cancer" and "gold nanoparticles and cancer". Though we reviewed many old papers, the most cited papers were from the last ten years.

RESULTS

Various studies indicate that AuNPs can enhance bioavailability, site-specific drug delivery, and efficacy of chemotherapy, radiotherapy, PTT, and PDT as well as modulate gene expression. The role of AuNPs in the modulation of TNBC therapeutics through the inhibition of cell proliferation, progression, and metastasis has been proved in vitro and in vivo studies. As these mechanistic actions of AuNPs are most desirable to develop drugs with enhanced therapeutic efficacy against TNBC, it might be a promising approach to apply AuNPs for TNBC therapeutics.

CONCLUSION

This article reviewed the mechanism of action of AuNPs and their application in the enhancement of therapeutics against TNBC. Much more attention is required for studying the role of AuNPs in developing them either as a single or synergistic anticancer agent against TNBC.

Therapeutic implications and clinical manifestations of thymoquinone

Thymoquinone (TQ), a natural phytochemical predominantly found in Nigella sativa, has been investigated for its numerous health benefits. TQ showed anti-cancer, anti-oxidant, and anti-inflammatory properties, validated in various disease models. The anti-cancer potential of TQ is goverened by anti-proliferation, cell cycle arrest, apoptosis induction, ROS production, anti-metastasis and anti-angiogenesis, inhibition of cell migration and invasion action. Additionally, TQ exhibited antitumor activity via the modulation of multiple pathways and molecular targets, including Akt, ERK1/2, STAT3, and NF-κB. The present review highlighted the anticancer potential of TQ . We summarize the anti-cancer, anti-oxidant, and anti-inflammatory properties of TQ, focusing on its molecular targets and its promising action in cancer therapy. We further described the molecular mechanisms by which TQ prevents signaling pathways that mediate cancer progression, invasion, and metastasis.

Bax/Bcl-2 Cascade Is Regulated by the EGFR Pathway: Therapeutic Targeting of Non-Small Cell Lung Cancer

Non-small cell lung carcinoma (NSCLC) comprises 80%-85% of lung cancer cases. EGFR is involved in several cancer developments, including NSCLC. The EGFR pathway regulates the Bax/Bcl-2 cascade in NSCLC. Increasing understanding of the molecular mechanisms of fundamental tumor progression has guided the development of numerous antitumor drugs. The development and improvement of rationally planned inhibitors and agents targeting particular cellular and biological pathways in cancer have been signified as a most important paradigm shift in the strategy to treat and manage lung cancer. Newer approaches and novel chemotherapeutic agents are required to accompany present cancer therapies for improving efficiency. Using natural products as a drug with an effective delivery system may benefit therapeutics. Naturally originated compounds such as phytochemicals provide crucial sources for novel agents/drugs and resources for tumor therapy. Applying the small-molecule inhibitors (SMIs)/phytochemicals has led to potent preclinical discoveries in various human tumor preclinical models, including lung cancer. In this review, we summarize recent information on the molecular mechanisms of the Bax/Bcl-2 cascade and EGFR pathway in NSCLC and target them for therapeutic implications. We further described the therapeutic potential of Bax/Bcl-2/EGFR SMIs, mainly those with more potent and selectivity, including gefitinib, EGCG, ABT-737, thymoquinone, quercetin, and venetoclax. In addition, we explained the targeting EGFR pathway and ongoing in vitro and in vivo and clinical investigations in NSCLC. Exploration of such inhibitors facilitates the future treatment and management of NSCLC.

Gene Expression Profiling and Protein Analysis Reveal Suppression of the C-Myc Oncogene and Inhibition JAK/STAT and PI3K/AKT/mTOR Signaling by Thymoquinone in Acute Myeloid Leukemia Cells

Overexpression of c-Myc plays an essential role in leukemogenesis and drug resistance, making c-Myc an attractive target for cancer therapy. However, targeting c-Myc directly is impossible, and c-Myc upstream regulator pathways could be targeted instead. This study investigated the effects of thymoquinone (TQ), a bioactive constituent in Nigella sativa, on the activation of upstream regulators of c-Myc: the JAK/STAT and PI3K/AKT/mTOR pathways in HL60 leukemia cells. Next-generation sequencing (NGS) was performed for gene expression profiling after TQ treatment. The expression of c-Myc and genes involved in JAK/STAT and PI3K/AKT/mTOR were validated by quantitative reverse transcription PCR (RT-qPCR). In addition, Jess assay analysis was performed to determine TQ’s effects on JAK/STAT and PI3K/AKT signaling and c-Myc protein expression. The results showed 114 significant differentially expressed genes after TQ treatment (p < 0.002). DAVID analysis revealed that most of these genes’ effect was on apoptosis and proliferation. There was downregulation of c-Myc, PI3K, AKT, mTOR, JAK2, STAT3, STAT5a, and STAT5b. Protein analysis showed that TQ also inhibited JAK/STAT and PI3K/AKT signaling, resulting in inhibition of c-Myc protein expression. In conclusion, the findings suggest that TQ potentially inhibits proliferation and induces apoptosis in HL60 leukemia cells by downregulation of c-Myc expression through inhibition of the JAK/STAT and PI3K/AKT signaling pathways.

Cytotoxic, apoptotic, and genetic evaluations of Nigella sativa essential oil nanoemulsion against human hepatocellular carcinoma cell lines

Background

Phytochemicals and plant extracts are showing promising anticancer potentials. In the current study, the volatile faction (essential oil) of Nigella sativa seeds was evaluated against some hepatocellular carcinoma (HCC). The essential oil was extracted and characterized by chromatographic techniques to reveal its chemical composition, especially thymoquinone. Then, the oil was fabricated in two nanoemulsion formulations (F1 and F2), which differ in their composition of surfactants. The cytotoxicity and apoptotic activities of the essential oil and its nanoemulsions were evaluated in vitro against HepG2 and Huh-7 cell lines. Normal WI-38 cell line was also included in that evaluation to study the selectivity and safety of the different formulations on normal cells.

Results

Gas chromatographic analysis indicated that the essential oil is composed mainly of p-cymene (40.0%), thymoquinone (31.2%) and trans-α-thujene (12.8%). Particle size of the nanoemulsions ranged between 9.4 and 119.7 nm depending on the type of surfactant used in the formulation process. The pure essential oil and its two nanoemulsions (F1 and F2) showed dose-dependent antiproliferative activity against both HCC cells. This activity reached its highest cell inhibition in the case of nanoemulsion (F2) where the proliferation percentage was only 21.9% and 9.2% against HepG2 and Huh-7 cells, respectively. The same nanoemulsion (F2) also showed the lowest IC50 values (55.7 and 35.5 µg/ml) against both HepG2 and Huh-7 cells, respectively, compared to 100 µg/ml for the reference drug Doxorubicin. Flow cytometric analysis also confirmed that nanoemulsion (F2) has the highest apoptotic activity compared to nanoemulsion (F1) and the pure unformulated essential oil. Genetic expressions of pro-apoptotic (Bax) and the anti-apoptotic (Bcl-2) gene markers evaluation revealed that nanoemulsion (F2) has better activity in upregulating (Bax) and down-regulate (Bcl-2) with the highest Bax/Bcl-2 ratio (69) was found against Huh-7 cells. All N. sativa nanoemulsions showed minimal cytotoxicity on the normal WI-38 cell, indicating wide safety margins due to selective properties.

Conclusion

Overall, the study revealed the potentials of N. sativa essential oil, after formulation in specially tailored nanoemulsion for application as potential adjuvant liver anticancer agent.

Graphical Abstract

Targeting microRNAs with thymoquinone: a new approach for cancer therapy

Cancer is a global disease involving transformation of normal cells into tumor types via numerous mechanisms, with mortality among all generations, in spite of the breakthroughs in chemotherapy, radiotherapy and/or surgery for cancer treatment. Since one in six deaths is due to cancer, it is one of the overriding priorities of world health. Recently, bioactive natural compounds have been widely recognized due to their therapeutic effects for treatment of various chronic disorders, notably cancer. Thymoquinone (TQ), the most valuable constituent of black cumin seeds, has shown anti-cancer characteristics in a wide range of animal models. The revolutionary findings have revealed TQ's ability to regulate microRNA (miRNA) expression, offering a promising approach for cancer therapy. MiRNAs are small noncoding RNAs that modulate gene expression by means of variation in features of mRNA. MiRNAs manage several biological processes including gene expression and cellular signaling pathways. Accordingly, miRNAs can be considered as hallmarks for cancer diagnosis, prognosis and therapy. The purpose of this study was to review the various molecular mechanisms by which TQ exerts its potential as an anti-cancer agent through modulating miRNAs.

Thymoquinone upregulates miR-125a-5p, attenuates STAT3 activation, and potentiates doxorubicin antitumor activity in murine solid Ehrlich carcinoma

In breast cancer, there has been evidence of atypical activation of signal transduction and activators of transcription 3 (STAT3). Thymoquinone (TQ) exerts its anti-neoplastic effect through diverse mechanisms, including STAT3 inhibition. The tumor suppressor, microRNA-125a-5p was reported to be downregulated in various breast cancer cells. Therefore, we investigated the influence of TQ and/or doxorubicin on microRNA-125a-5p and its correlation with STAT3 activation as well as tumor growth in mice bearing solid Ehrlich tumors. We found that TQ markedly suppressed inducible and constitutive phosphorylation of STAT3 in tumor tissue without affecting STAT5. Moreover, it attenuated tumor growth, downregulated STAT3 downstream target proteins, and increased the apoptotic activities of caspase-3 and -9. Interestingly, TQ-elicited synergism of doxorubicin anti-neoplastic activity was coupled with upregulation of tumoral microRNA-125a-5p. Taken together, the current findings raise the potential of TQ as a promising chemomodulatory adjuvant to augment mammary carcinoma sensitivity to doxorubicin.

LPS/TLR4 pathways in breast cancer: insights into cell signalling

BACKGROUND

Cancer cells are usually recognized as foreign particles by the immune cells. Mounting evidences suggest important link between toll like receptors (TLRs) and carcinogenesis. This review article focused on the role of TLRs, especially TLR4 in breast cancer. <p> Methods: Research data on TLRs and cancer was explored in PubMed, Scopus, Google Scholar, and reviewed. Although some pioneer works are referenced, papers published in last ten years were mostly cited. <p> Results: TLRs are widely investigated pattern recognition receptors (PRR), and TLR4 is the most studied TLRs, implicated with occurrence of several types of cancers including breast cancer. TLR4 activation occurs via the binding of its ligand lipopolysaccharide (LPS), a component of the outer membrane of gram negative bacteria. Upon LPS binding, TLR4 dimerizes and recruits downstream signalling and/or adapter molecules leading to gene expression related to cancer cell proliferation, survival, invasion, and metastasis. Although LPS/TLR4 signalling seems a single signal transduction pathway, the TLR4 activation results in the activation of multiple diverse intracellular networks with huge cellular responses in both immune and cancer cells. The role of TLR4 in growth, invasion and metastasis of breast cancer is attracting huge attention in oncology research. Several clinical and preclinical studies utilize both TLR4 agonists and antagonists as treatment option for cancer therapy either as monotherapy or adjuvants for vaccine development. <p> Conclusion: This review narrates the role of LPS/TLR4 signalling in breast cancer development and future prospective for targeting LPS/TLR4 axis in the treatment of breast cancer.

Nature-derived hit, lead, and drug-like small molecules: Current status and future aspects against key target proteins of Coronaviruses

BACKGROUND

COVID-19 pandemic, the most unprecedented event of the year 2020, has brought millions of scientists worldwide in a single platform to fight against it. Though several drugs are now in the clinical trial, few vaccines available on the market already but the lack of an effect of those is making the situation worse.

AIM OF THE STUDY

In this review, we demonstrated comprehensive data of natural antiviral products showing activities against different proteins of Human Coronaviruses (HCoV) that are responsible for its pathogenesis. Furthermore, we categorized the compounds into the hit, lead, and drug based on the IC50/EC50 value, drug-likeness, and lead-likeness test to portray their potentiality to be a drug. We also demonstrated the present status of our screened antiviral compounds with respect to clinical trials and reported the lead compounds that can be promoted to clinical trial against COVID-19.

METHODS

A systematic search strategy was employed focusing on Natural Products (NPs) with proven activity (in vitro, in vivo, or in silico) against human coronaviruses, in general, and data were gathered from databases like PubMed, Web of Science, Google Scholar, SciVerse, and Scopus. Information regarding clinical trials retrieved from the Clinical Trial database.

RESULTS

Total "245" natural compounds were identified initially from the literature study. Among them, Glycyrrhizin, Caffeic acid, Curcumin is in phase 3, and Tetrandrine, Cyclosporine, Tacrolimus, Everolimus are in phase 4 clinical trial. Except for Glycyrrhizin, all compounds showed activity against COVID-19.

CONCLUSIONS

In summary, our demonstrated specific small molecules with lead and drug-like capabilities clarified their position in the drug discovery pipeline and proposed their future research against COVID-19.

On the Role of Paraoxonase-1 and Chemokine Ligand 2 (C-C motif) in Metabolic Alterations Linked to Inflammation and Disease. A 2021 Update

Infectious and many non-infectious diseases share common molecular mechanisms. Among them, oxidative stress and the subsequent inflammatory reaction are of particular note. Metabolic disorders induced by external agents, be they bacterial or viral pathogens, excessive calorie intake, poor-quality nutrients, or environmental factors produce an imbalance between the production of free radicals and endogenous antioxidant systems; the consequence being the oxidation of lipids, proteins, and nucleic acids. Oxidation and inflammation are closely related, and whether oxidative stress and inflammation represent the causes or consequences of cellular pathology, both produce metabolic alterations that influence the pathogenesis of the disease. In this review, we highlight two key molecules in the regulation of these processes: Paraoxonase-1 (PON1) and chemokine (C-C motif) ligand 2 (CCL2). PON1 is an enzyme bound to high-density lipoproteins. It breaks down lipid peroxides in lipoproteins and cells, participates in the protection conferred by HDL against different infectious agents, and is considered part of the innate immune system. With PON1 deficiency, CCL2 production increases, inducing migration and infiltration of immune cells in target tissues and disturbing normal metabolic function. This disruption involves pathways controlling cellular homeostasis as well as metabolically-driven chronic inflammatory states. Hence, an understanding of these relationships would help improve treatments and, as well, identify new therapeutic targets.

Biological Role of AKT and Regulation of AKT Signaling Pathway by Thymoquinone: Perspectives in Cancer Therapeutics

BACKGROUND

AKT/PKB is an important enzyme with numerous biological functions, and its overexpression is related to carcinogenesis. AKT stimulates different signaling pathways that are downstream of activated tyrosine kinases and phosphatidylinositol 3-kinase, hence functions as an important target for anti-cancer drugs.

OBJECTIVE

In this review article, we have interpreted the role of AKT signaling pathway in cancer and the natural inhibitory effect of Thymoquinone (TQ) in AKT and its possible mechanisms.

METHOD

We have collected the updated information and data on AKT, its role in cancer and the inhibitory effect of TQ in AKT signaling pathway from Google Scholar, PubMed, Web of Science, Elsevier, Scopus, and many more.

RESULTS

Many drugs are already developed, which can target AKT, but very few among them have passed clinical trials. TQ is a natural compound, mainly found in black cumin, which has been found to have potential anti-cancer activities. TQ targets numerous signaling pathways, including AKT, in different cancers. In fact, many studies revealed that AKT is one of the major targets of TQ. The preclinical success of TQ suggests its clinical studies on cancer.

CONCLUSION

This review article summarizes the role of AKT in carcinogenesis, its potent inhibitors in clinical trials, and how TQ acts as an inhibitor of AKT and TQ's future as a cancer therapeutic drug.

Multiple Myeloma Inhibitory Activity of Plant Natural Products

A literature search on plant natural products with antimyeloma activity until the end of 2020 resulted in 92 compounds with effects on at least one human myeloma cell line. Compounds were divided in different compound classes and both their structure-activity-relationships as well as eventual correlations with the pathways described for Multiple Myeloma were discussed. Each of the major compound classes in this review (alkaloids, phenolics, terpenes) revealed interesting candidates, such as dioncophyllines, a group of naphtylisoquinoline alkaloids, which showed pronounced and selective induction of apoptosis when substituted in position 7 of the isoquinoline moiety. Interestingly, out of the phenolic compound class, two of the most noteworthy constituents belong to the relatively small subclass of xanthones, rendering this group a good starting point for possible further drug development. The class of terpenoids also provides noteworthy constituents, such as the highly oxygenated diterpenoid oridonin, which exhibited antiproliferative effects equal to those of bortezomib on RPMI8226 cells. Moreover, triterpenoids containing a lactone ring and/or quinone-like substructures, e.g., bruceantin, whitaferin A, withanolide F, celastrol, and pristimerin, displayed remarkable activity, with the latter two compounds acting as inhibitors of both NF-κB and proteasome chymotrypsin-like activity.

Recent Findings on Thymoquinone and Its Applications as a Nanocarrier for the Treatment of Cancer and Rheumatoid Arthritis

Cancer causes a considerable amount of mortality in the world, while arthritis is an immunological dysregulation with multifactorial pathogenesis including genetic and environmental defects. Both conditions have inflammation as a part of their pathogenesis. Resistance to anticancer and disease-modifying antirheumatic drugs (DMARDs) happens frequently through the generation of energy-dependent transporters, which lead to the expulsion of cellular drug contents. Thymoquinone (TQ) is a bioactive molecule with anticancer as well as anti-inflammatory activities via the downregulation of several chemokines and cytokines. Nevertheless, the pharmacological importance and therapeutic feasibility of thymoquinone are underutilized due to intrinsic pharmacokinetics, including short half-life, inadequate biological stability, poor aqueous solubility, and low bioavailability. Owing to these pharmacokinetic limitations of TQ, nanoformulations have gained remarkable attention in recent years. Therefore, this compilation intends to critically analyze recent advancements in rheumatoid arthritis and cancer delivery of TQ. This literature search revealed that nanocarriers exhibit potential results in achieving targetability, maximizing drug internalization, as well as enhancing the anti-inflammatory and anticancer efficacy of TQ. Additionally, TQ-NPs (thymoquinone nanoparticles) as a therapeutic payload modulated autophagy as well as enhanced the potential of other drugs when given in combination. Moreover, nanoformulations improved pharmacokinetics, drug deposition, using EPR (enhanced permeability and retention) and receptor-mediated delivery, and enhanced anti-inflammatory and anticancer properties. TQ's potential to reduce metal toxicity, its clinical trials and patents have also been discussed.

Thymoquinone, a Dietary Bioactive Compound, Exerts Anti-Inflammatory Effects in Colitis by Stimulating Expression of the Colonic Epithelial PPAR-γ Transcription Factor

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders with increasing incidence and prevalence worldwide. Here, we investigated thymoquinone (TQ), a naturally occurring phytochemical present in Nigella sativa, for anti-inflammatory effects in colonic inflammation. To address this, we used in vivo (mice) and in vitro (HT-29 cells) models in this investigation. Our results showed that TQ treatment significantly reduced the disease activity index (DAI), myeloperoxidase (MPO) activity, and protected colon microscopic architecture. In addition, TQ also reduced the expression of proinflammatory cytokines and mediators at both the mRNA and protein levels. Further, TQ decreased phosphorylation of the activated mitogen-activated protein kinase (MAPK) signaling pathway and nuclear factor kappa B (NF-κB) proteins and enhanced colon epithelial PPAR-γ transcription factor expression. TQ significantly decreased proinflammatory chemokines (CXCL-1 and IL-8), and mediator (COX-2) mRNA expression in HT-29 cells treated with TNF-α. TQ also increased HT-29 PPAR-γ mRNA, PPAR-γ protein expression, and PPAR-γ promoter activity. These results indicate that TQ inhibits MAPK and NF-κB signaling pathways and transcriptionally regulates PPAR-γ expression to induce potent anti-inflammatory activity in vivo and in vitro models of colon inflammation.

Thymoquinone in autoimmune diseases: Therapeutic potential and molecular mechanisms

Autoimmune diseases (AUDs) are a multifactorial disease, among which rheumatoid arthritis, systemic lupus erythematosus and multiple sclerosis are more prevalent. Several anti-inflammatory, biologics, and AUD-modifying drugs are found effective against them, but their repeated use are associated with various adverse effects. In this review article, we have focused on the regulation of inflammatory molecules, molecular signaling pathways, immune cells, and epigenetics by natural product thymoquinone on AUDs. Studies indicate that thymoquinone can regulate inflammatory molecules including interferons, interleukins, tumor necrosis factor-α (TNF-α), oxidative stress, regulatory T cells, and various signaling pathways such as nuclear factor kappa beta (NF-κβ), janus kinase/signal transduction and activator of transcription (JAK-STAT), mitogen-activated protein kinase (MAPK) at the molecular level and epigenetic alteration. As these molecules and signaling pathways with defective immune function play an important role in AUD development, controlling these molecules and deregulated molecular mechanism is a significant feature of AUD therapeutics. Interestingly thymoquinone is reported to possess all these potential. This article reviewed the deregulated mechanism of AUDs, and the action of thymoquinone on inflammatory molecules, immune cells, signaling pathways, and epigenetic machinery. Thymoquinone can be regarded as a potential drug candidate for AUD treatment.