Thymoquinone exerts potent growth-suppressive activity on leukemia through DNA hypermethylation reversal in leukemia cells

Management of triple-negative breast cancer by natural compounds through different mechanistic pathways

Triple-negative breast cancer (TNBC) is the most severe form of breast cancer, characterized by the loss of estrogen, progesterone, and human epidermal growth factor receptors. It is caused by various genetic and epigenetic factors, resulting in poor prognosis. Epigenetic changes, such as DNA methylation and histone modification, are the leading mechanisms responsible for TNBC progression and metastasis. This review comprehensively covers the various subtypes of TNBC and their epigenetic causes. In addition, the genetic association of TNBC with all significant genes and signaling pathways linked to the progression of this form of cancer has been enlisted. Furthermore, the possible uses of natural compounds through different mechanistic pathways have also been discussed in detail for the successful management of TNBC.

Emerging DNA Methylome Targets in FLT3-ITD-Positive Acute Myeloid Leukemia: Combination Therapy with Clinically Approved FLT3 Inhibitors

OPINION STATEMENT

The internal tandem duplication (ITD) mutation of the FMS-like receptor tyrosine kinase 3 (FLT3-ITD) is the most common mutation observed in approximately 30% of acute myeloid leukemia (AML) patients. It represents poor prognosis due to continuous activation of downstream growth-promoting signaling pathways such as STAT5 and PI3K/AKT. Hence, FLT3 is considered an attractive druggable target; selective small FLT3 inhibitors (FLT3Is), such as midostaurin and quizartinib, have been clinically approved. However, patients possess generally poor remission rates and acquired resistance when FLT3I used alone. Various factors in patients could cause these adverse effects including altered epigenetic regulation, causing mainly abnormal gene expression patterns. Epigenetic modifications are required for hematopoietic stem cell (HSC) self-renewal and differentiation; however, critical driver mutations have been identified in genes controlling DNA methylation (such as DNMT3A, TET2, IDH1/2). These regulators cause leukemia pathogenesis and affect disease diagnosis and prognosis when they co-occur with FLT3-ITD mutation. Therefore, understanding the role of different epigenetic alterations in FLT3-ITD AML pathogenesis and how they modulate FLT3I's activity is important to rationalize combinational treatment approaches including FLT3Is and modulators of methylation regulators or pathways. Data from ongoing pre-clinical and clinical studies will further precisely define the potential use of epigenetic therapy together with FLT3Is especially after characterized patients' mutational status in terms of FLT3 and DNA methlome regulators.

Natural bioactive compounds targeting DNA methyltransferase enzymes in cancer: Mechanisms insights and efficiencies

The regulation of gene expression is fundamental to health and life and is essentially carried out at the promoter region of the DNA of each gene. Depending on the molecular context, this region may be accessible or non-accessible (possibility of integration of RNA polymerase or not at this region). Among enzymes that control this process, DNA methyltransferase enzymes (DNMTs), are responsible for DNA demethylation at the CpG islands, particularly at the promoter regions, to regulate transcription. The aberrant activity of these enzymes, i.e. their abnormal expression or activity, can result in the repression or overactivation of gene expression. Consequently, this can generate cellular dysregulation leading to instability and tumor development. Several reports highlighted the involvement of DNMTs in human cancers. The inhibition or activation of DNMTs is a promising therapeutic approach in many human cancers. In the present work, we provide a comprehensive and critical summary of natural bioactive molecules as primary inhibitors of DNMTs in human cancers. The active compounds hold the potential to be developed as anti-cancer epidrugs targeting DNMTs.

In Vitro and In Vivo Preventive Effects of Thymoquinone against Breast Cancer: Role of DNMT1

Breast cancer (BC) is one of the most common cancers in women and is a major cause of female cancer-related deaths. BC is a multifactorial disease caused by the dysregulation of many genes, raising the need to find novel drugs that function by targeting several signaling pathways. The antitumoral drug thymoquinone (TQ), found in black seed oil, has multitargeting properties against several signaling pathways. This study evaluated the inhibitory effects of TQ on the MCF7 and T47D human breast cancer cell lines and its antitumor activity against BC induced by a single oral dose (65 mg/kg) of 7,12-dimethylbenzanthracene (DMBA) in female rats. The therapeutic activity was evaluated in DMBA-treated rats who received oral TQ (50 mg/kg) three times weekly. TQ-treated MCF7 and T47D cells showed concentration-dependent inhibition of cell proliferation and induction of apoptosis. TQ also decreased the expression of DNA methyltransferase 1 (DNMT1) in both cancer cell types. In DMBA-treated animals, TQ inhibited the number of liver and kidney metastases. These effects were associated with a reduction in DNMT1 mRNA expression. These results indicate that TQ has protective effects against breast carcinogens through epigenetic mechanisms involving DNMT1 inhibition.

Recent Advances in Natural Products with Anti-Leukemia and Anti- Lymphoma Activities

Leukemia and lymphoma are the most common blood cancers, which pose a critical threat to the health of adults and children. The total incidence and mortality rates of both are approximately 6% globally. Compared with the expensive cost of CAR T cell therapy, natural products from animals, plants and microorganisms have the characteristics of wide-range sources and costeffectiveness in the treatment of cancer. Moreover, the drug resistance that emerged in leukemia and lymphoma treatments shows an urgent need for new drugs. However, in addition to the natural products that have been marketed in the treatment of leukemia and lymphoma, there have been a large number of studies on natural products that fight blood cancer in recent years. This review summarized the recent studies on natural compounds with anti-lymphoma and anti-leukemia activities, hoping to provide novel weapons into the drug development arsenal.

Thymoquinone Enhances Apoptosis of K562 Chronic Myeloid Leukemia Cells through Hypomethylation of SHP-1 and Inhibition of JAK/STAT Signaling Pathway

The epigenetic silencing of tumor suppressor genes (TSGs) is critical in the development of chronic myeloid leukemia (CML). SHP-1 functions as a TSG and negatively regulates JAK/STAT signaling. Enhancement of SHP-1 expression by demethylation provides molecular targets for the treatment of various cancers. Thymoquinone (TQ), a constituent of Nigella sativa seeds, has shown anti-cancer activities in various cancers. However, TQs effect on methylation is not fully clear. Therefore, the aim of this study is to assess TQs ability to enhance the expression of SHP-1 through modifying DNA methylation in K562 CML cells. The activities of TQ on cell cycle progression and apoptosis were evaluated using a fluorometric-red cell cycle assay and Annexin V-FITC/PI, respectively. The methylation status of SHP-1 was studied by pyrosequencing analysis. The expression of SHP-1, TET2, WT1, DNMT1, DNMT3A, and DNMT3B was determined using RT-qPCR. The protein phosphorylation of STAT3, STAT5, and JAK2 was assessed using Jess Western analysis. TQ significantly downregulated the DNMT1 gene, DNMT3A gene, and DNMT3B gene and upregulated the WT1 gene and TET2 gene. This led to hypomethylation and restoration of SHP-1 expression, resulting in inhibition of JAK/STAT signaling, induction of apoptosis, and cell cycle arrest. The observed findings imply that TQ promotes apoptosis and cell cycle arrest in CML cells by inhibiting JAK/STAT signaling via restoration of the expression of JAK/STAT-negative regulator genes.

Epigenetic regulation in hematopoiesis and its implications in the targeted therapy of hematologic malignancies

Hematologic malignancies are one of the most common cancers, and the incidence has been rising in recent decades. The clinical and molecular features of hematologic malignancies are highly heterogenous, and some hematologic malignancies are incurable, challenging the treatment, and prognosis of the patients. However, hematopoiesis and oncogenesis of hematologic malignancies are profoundly affected by epigenetic regulation. Studies have found that methylation-related mutations, abnormal methylation profiles of DNA, and abnormal histone deacetylase expression are recurrent in leukemia and lymphoma. Furthermore, the hypomethylating agents and histone deacetylase inhibitors are effective to treat acute myeloid leukemia and T-cell lymphomas, indicating that epigenetic regulation is indispensable to hematologic oncogenesis. Epigenetic regulation mainly includes DNA modifications, histone modifications, and noncoding RNA-mediated targeting, and regulates various DNA-based processes. This review presents the role of writers, readers, and erasers of DNA methylation and histone methylation, and acetylation in hematologic malignancies. In addition, this review provides the influence of microRNAs and long noncoding RNAs on hematologic malignancies. Furthermore, the implication of epigenetic regulation in targeted treatment is discussed. This review comprehensively presents the change and function of each epigenetic regulator in normal and oncogenic hematopoiesis and provides innovative epigenetic-targeted treatment in clinical practice.

Advances in research on the relationship between thymoquinone and pancreatic cancer

Pancreatic cancer has one of the worst prognoses among the most common cancers in the world. Its characteristics include a high rate of metastasis and chemotherapeutic resistance, which present major challenges to the medical community. The potential anticancer effects of thymoquinone (TQ), which is the main bioactive compound of the black seeds of the Nigella sativa plant, have recently received widespread attention for their potential use in treating pancreatic cancer. TQ can inhibit cell proliferation, promote cancer cell apoptosis, inhibit cell invasion and metastasis, enhance chemotherapeutic sensitivity, inhibit angiogenesis, and exert anti-inflammatory effects. These anticancer effects predominantly involve the nuclear factor (NF)-κB, phosphoinositide 3 kinase (PI3K)/Akt, Notch, transforming growth factor (TGF)-β, c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) signaling pathways as well as the regulation of the cell cycle, matrix metallopeptidase (MMP)-9 expression, and pyruvate kinase isozyme type M2 (PKM2) activity. TQ regulates the occurrence and development of pancreatic cancer at multiple levels and through multiple targets that communicate with each other. In this review, we summarize and discuss the analogs and carriers of TQ that have been developed in recent years. Given its multilevel anticancer effects, TQ may become a new therapeutic drug for treating pancreatic cancer in the future. This review presents a brief introduction to the research that has been conducted on TQ in relation to pancreatic cancer to provide a theoretical basis for future studies on the topic.

Response of Skin-Derived and Metastatic Human Malignant Melanoma Cell Lines to Thymoquinone and Thymoquinone-Loaded Liposomes

Thymoquinone has been proved to be effective against neoplasms, including skin cancer. Its high lipophilicity, however, may limit its potential use as a drug. Melanoma remains the deadliest of all skin cancers worldwide, due to its high heterogeneity, depending on the stage of the disease. Our goal was to compare the anti-cancer activity of free thymoquinone and thymoquinone-loaded liposomes on two melanoma cell lines that originated from different stages of this cancer: skin-derived A375 and metastatic WM9. We evaluated the proapoptotic effects of free thymoquinone by flow cytometry and Western blot, and its mitotoxicity by means of JC-1 assay. Additionally, we compared the cytotoxicity of free thymoquinone and thymoquinone in liposomes by WST-1 assay. Our results revealed a higher antiproliferative effect of TQ in WM9 cells, whereas its higher proapoptotic activity was observed in the A375 cell line. Moreover, the thymoquinone-loaded liposome was proved to exert stronger cytotoxic effect on both cell lines studied than free thymoquinone. Differences in the response of melanoma cells derived from different stages of the disease to thymoquinone, as well as their different responses to free and carrier-delivered thymoquinone, are essential for the development of new anti-melanoma therapies. However, further research is required to fully understand them.

Thymoquinone Inhibits JAK/STAT and PI3K/Akt/ mTOR Signaling Pathways in MV4-11 and K562 Myeloid Leukemia Cells

Constitutive activation of Janus tyrosine kinase-signal transducer and activator of transcription (JAK/STAT) and Phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathways plays a crucial role in the development of acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). Thymoquinone (TQ), one of the main constituents of Nigella sativa, has shown anti-cancer activities in several cancers. However, the inhibitory effect mechanism of TQ on leukemia has not been fully understood. Therefore, this study aimed to investigate the effect of TQ on JAK/STAT and PI3K/Akt/mTOR pathways in MV4-11 AML cells and K562 CML cells. FLT3-ITD positive MV4-11 cells and BCR-ABL positive K562 cells were treated with TQ. Cytotoxicity assay was assessed using WSTs-8 kit. The expression of the target genes was evaluated using RT-qPCR. The phosphorylation status and the levels of proteins involved in JAK/STAT and PI3K/Akt/mTOR pathways were investigated using Jess western analysis. TQ induced a dose and time dependent inhibition of K562 cells proliferation. TQ significantly downregulated PI3K, Akt, and mTOR and upregulated PTEN expression with a significant inhibition of JAK/STAT and PI3K/Akt/mTOR signaling. In conclusion, TQ reduces the expression of PI3K, Akt, and mTOR genes and enhances the expression of PTEN gene at the mRNA and protein levels. TQ also inhibits JAK/STAT and PI3K/Akt/mTOR pathways, and consequently inhibits proliferation of myeloid leukemia cells, suggesting that TQ has potential anti-leukemic effects on both AML and CML cells.

The effects of thymoquinone on pancreatic cancer: Evidence from preclinical studies

Thymoquinone (TQ) is a secondary metabolite found in abundance in very few plant species including Nigella sativa L., Monarda fistulosa L., Thymus vulgaris L. and Satureja montana L. Preclinical pharmacological studies have shown that TQ has many biological activities, such as anti-inflammatory, antioxidant and anticancer. Both in vivo and in vitro experiments have shown that TQ acts as an antitumor agent by altering cell cycle progression, inhibiting cell proliferation, stimulating apoptosis, inhibiting angiogenesis, reducing metastasis and affecting autophagy. In this comprehensive study, the evidence on the pharmacological potential of TQ on pancreatic cancer is reviewed. The positive results of preclinical studies support the view that TQ can be considered as an additional therapeutic agent against pancreatic cancer. The possibilities of success for this compound in human medicine should be further explored through clinical trials.

Modulation of miR-192/NF-κB/ TGF-β/ E-cadherin by thymoquinone protects against diethylnitrosamine /carbon tetrachloride hepatotoxicity

Scientific efforts have been made for a better understanding of the pathogenesis of hepatocellular carcinoma (HCC). We investigated the possible role of miR-192/nuclear factor-κB (NF-κB)/transforming growth factor-β (TGF-β)/E-cadherin in hepatic tumorigenesis. We expected a modulatory impact of thymoquinone. Thirty adult male rats were assigned into 3 groups (n = 10); (1) Control group. Group (2): Experimental HCC induced by intraperitoneal injection of diethylnitrosamine (DENA) followed by carbon tetrachloride (CCl4). Group (3): Thymoquinone 20 mg kg-1/oral supplementation starting from the model induction to the end of the 8th week. The HCC (DENA-CCL4) model was confirmed by elevated serum levels of alpha-fetoprotein and transaminases (ALT, AST) and by histopathological examination which denoted marked cellular atypia and features of neoplasia. Suppressed hepatic miR-192 and E-cadherin expression were detected in the HCC (DENA-CCL4) group accompanied by elevated tumor necrosis factor (TNF-α), interleukin (IL6)/NF-κB & TGF-β1. Thymoquinone treatment protected the rat livers from hepatic tumorigenesis. Thymoquinone diminished (P < 0.001) alpha-fetoprotein and improved ALT, AST. It preserved hepatic miR-192 and normal E-cadherin expression. Thymoquinone-treated rats showed abrogated TNF-α, IL6/NF-κB/TGF-β. Thymoquinone increased cell apoptosis markers Bax/Bcl2 and diminished cellular atypia. Pearson's correlations revealed positive association between miR-192 expression and E-cadherin and Bax/Bcl2 as well, and it was negatively correlated to alpha-fetoprotein, NF-κB and TGF-β and the cellular atypia score. In conclusion, thymoquinone protected the liver tissues through preserving miR-192 and E-cadherin and aborting NF-κB & TGF-β signaling. The current results highlight a new role for thymoquinone in preventing hepatic tumorigenesis.

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.

Thymoquinone upregulates IL17RD in controlling the growth and metastasis of triple negative breast cancer cells in vitro

Background

Triple negative breast cancer (TNBC) is a molecular subtype of breast cancer, which is a major health burden of females worldwide. Thymoquinone (TQ), a natural compound, has been found to be effective against TNBC cells, and this study identified IL17RD as a novel target of TQ in TNBC cells.

Methods

We have performed chromatin immunoprecipitation Sequence (ChIP-Seq) by MBD1 (methyl-CpG binding domain protein 1) antibody to identify genome-wide methylated sites affected by TQ. ChIP-seq identified 136 genes, including the tumor suppressor IL17RD, as a novel target of TQ, which is epigenetically upregulated by TQ in TNBC cell lines BT-549 and MDA-MB-231. The IL17RD expression and survival outcomes were studied by Kaplan–Meier analysis.

Results

TQ treatment inhibited the growth, migration, and invasion of TNBC cells with or without IL17RD overexpression or knockdown, while the combination of IL17RD overexpression and TQ treatment were the most effective against TNBC cells. Moreover, higher expression of IL17RD is associated with longer survival in TNBC patients, indicating potential therapeutic roles of TQ and IL17RD against TNBC.

Conclusions

Our data suggest that IL17RD might be epigenetically upregulated in TNBC cell lines by TQ, and this might be one of the mechanisms by which TQ exerts its anticancer and antimetastatic effects on TNBC cells.

The Potential Role of Nigella sativa Seed Oil as Epigenetic Therapy of Cancer

Nigella sativa oil, commonly known as black seed oil (BSO), is a well-known Mediterranean food, and its consumption is associated with beneficial effects on human health. A large number of BSO's therapeutic properties is attributed to its pharmacologically active compound, thymoquinone (TQ), which inhibits cell proliferation and induces apoptosis by targeting several epigenetic players, including the ubiquitin-like, containing plant homeodomain (PHD) and an interesting new gene, RING finger domains 1 (UHRF1), and its partners, DNA methyltransferase 1 (DNMT1) and histone deacetylase 1 (HDAC1). This study was designed to compare the effects of locally sourced BSO with those of pure TQ on the expression of the epigenetic complex UHRF1/DNMT1/HDAC1 and the related events in several cancer cells. The gas chromatographs obtained from GC-MS analyses of extracted BSO showed that TQ was the major volatile compound. BSO significantly inhibited the proliferation of MCF-7, HeLa and Jurkat cells in a dose-dependent manner, and it induced apoptosis in these cell lines. BSO-induced inhibitory effects were associated with a significant decrease in mRNA expression of UHRF1, DNMT1 and HDAC1. Molecular docking and MD simulation showed that TQ had good binding affinity to UHRF1 and HDAC1. Of note, TQ formed a stable metal coordinate bond with zinc tom, found in the active site of the HDAC1 protein. These findings suggest that the use of TQ-rich BSO represents a promising strategy for epigenetic therapy for both solid and blood tumors through direct targeting of the trimeric epigenetic complex UHRF1/DNMT1/ HDAC1.

Metformin and Thymoquinone Synergistically Inhibit Proliferation of Imatinib-Resistant Human Leukemic Cells

Chemotherapy resistance is one of the major challenges in cancer treatment, including leukemia. A massive array of research is evaluating combinations of drugs directed against different intracellular signaling molecules to overcome cancer resistance, increase therapy effectiveness, and decrease its adverse effects. Combining chemicals with proven safety profiles, such as drugs already used in therapy and active substances isolated from natural sources, could potentially have superior effects compared to monotherapies. In this study, we evaluated the effects of metformin and thymoquinone (TQ) as monotherapy and combinatorial treatments in chronic myeloid leukemia (CML) cell lines sensitive and resistant to imatinib therapy. The effects were also evaluated in primary monocytic acute myeloid leukemia (AML) and chronic lymphocytic leukemia (CLL) cells. Both compounds induced a dose- and time-dependent decrease of viability and proliferation in tested cells. Metformin had similar IC₅₀ values in imatinib-sensitive and imatinib-resistant cell lines. IC₅₀ values of TQ were significantly higher in imatinib-resistant cells, but with a limited resistance index (2.4). Synergistic effects of combinatorial treatments were observed in all tested cell lines, as well as in primary cells. The strongest synergistic effects were observed in the inhibition of imatinib-resistant cell line proliferation. Metformin and TQ inhibited the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling and induced apoptosis in tested cell lines and primary cells. The enhanced effects of combinatorial treatments on the induction of apoptosis were more dominant in imatinib-resistant compared to imatinib-sensitive CML cells. Primary cells were more sensitive to combinatorial treatments compared to cell lines. A combination of 1.25 mM metformin and 0.625 µM TQ increased the levels of cleaved poly (ADP-ribose) polymerase (PARP), decreased the levels of proliferation regulatory proteins, and inhibited protein kinase B (Akt) and NF-κB signaling in primary CLL cells. This study demonstrates that combinatorial treatments of imatinib-resistant malignant clones with metformin and TQ by complementary intracellular multi-targeting represents a promising approach in future studies.

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.

Thymoquinone Inhibits Growth of Acute Myeloid Leukemia Cells through Reversal SHP-1 and SOCS-3 Hypermethylation: In Vitro and In Silico Evaluation

Epigenetic silencing of tumor suppressor genes (TSGs) plays an essential role in cancer pathogenesis, including acute myeloid leukemia (AML). All of SHP-1, SOCS-1, and SOCS-3 are TSGs that negatively regulate JAK/STAT signaling. Enhanced re-expression of TSGs through de-methylation represents a therapeutic target in several cancers. Thymoquinone (TQ) is a major component of Nigella sativa seeds with anticancer effects against several cancers. However, the effects of TQ on DNA methylation are not entirely understood. This study aimed to evaluate the ability of TQ to re-express SHP-1, SOCS-1, and SOCS-3 in MV4-11 AML cells through de-methylation. Cytotoxicity, apoptosis, and cell cycle assays were performed using WSTs-8 kit, Annexin V-FITC/PI apoptosis detection kit, and fluorometric-red cell cycle assay kit, respectively. The methylation of SHP-1, SOCS-1, and SOCS-3 was evaluated by pyrosequencing analysis. The expression of SHP-1, SOCS-1, SOCS-3, JAK2, STAT3, STAT5A, STAT5B, FLT3-ITD, DNMT1, DNMT3A, DNMT3B, TET2, and WT1 was assessed by RT-qPCR. The molecular docking of TQ to JAK2, STAT3, and STAT5 was evaluated. The results revealed that TQ significantly inhibited the growth of MV4-11 cells and induced apoptosis in a dose- and time-dependent manner. Interestingly, the results showed that TQ binds the active pocket of JAK2, STAT3, and STAT5 to inhibit their enzymatic activity and significantly enhances the re-expression of SHP-1 and SOCS-3 through de-methylation. In conclusion, TQ curbs MV4-11 cells by inhibiting the enzymatic activity of JAK/STAT signaling through hypomethylation and re-expression of JAK/STAT negative regulators and could be a promising therapeutic candidate for AML patients.

Natural Bioactive Compounds Targeting Epigenetic Pathways in Cancer: A Review on Alkaloids, Terpenoids, Quinones, and Isothiocyanates

Cancer is one of the most complex and systemic diseases affecting the health of mankind, causing major deaths with a significant increase. This pathology is caused by several risk factors, of which genetic disturbances constitute the major elements, which not only initiate tumor transformation but also epigenetic disturbances which are linked to it and which can induce transcriptional instability. Indeed, the involvement of epigenetic disturbances in cancer has been the subject of correlations today, in addition to the use of drugs that operate specifically on different epigenetic pathways. Natural molecules, especially those isolated from medicinal plants, have shown anticancer effects linked to mechanisms of action. The objective of this review is to explore the anticancer effects of alkaloids, terpenoids, quinones, and isothiocyanates.

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.

Epigenetics of Triple-negative breast cancer via natural compounds

Triple-negative breast cancer (TNBC) is a highly resistant, lethal, and metastatic sub-division of breast carcinoma, characterized by the deficiency of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). In women, TNBC shows a higher aggressive behavior with poor patient prognosis and a higher recurrence rate during reproductive age. TNBC is defined by the presence of epithelial-to-mesenchymal-transition (EMT), which shows a significant role in cancer progression. At the epigenetic level, TNBC is characterized by epigenetic signatures, such as DNA methylation, histone remodeling, and a host of miRNA, MiR-193, LncRNA, HIF-2α, eEF2K, LIN9/NEK2, IMP3, LISCH7/TGF-β1, GD3s and KLK12 mediated regulation. These modifications either are silenced or activate the necessary genes that are prevalent in TNBC. The review is based on epigenetic mediated mechanistic changes in TNBC. Furthermore, Thymoquinone (TQ), Regorafenib, Fangjihuangqi decoction, Saikosaponin A, and Huaier, etc., are potent antitumor natural compounds extensively reported in the literature. Further, the review emphasizes the role of these natural compounds in TNBC and their possible epigenetic targets, which can be utilized as a potential therapeutic strategy in treatment of TNBC.

Therapeutic perspectives of the black cumin component thymoquinone: A review

The dietary phytochemical thymoquinone (TQ), belonging to the family of quinones, mainly obtained from the black and angular seeds of Nigella sativa, is one of the promising monoterpenoid hydrocarbons, which has been receiving massive attention for its therapeutic potential and pharmacological properties. It plays an important role as a chemopreventive and therapeutic agent in the treatment of various diseases and illnesses. The aim of this review is to present a summary of the most recent literature pertaining to the use of TQ for the prevention and treatment of various diseases along with possible mechanisms of action, and the potential use of this natural product as a complementary or alternative medicine. Research findings indicated that TQ exhibits numerous pharmacological activities including antioxidant, anti-inflammatory, cardioprotective, hepatoprotective, antidiabetic, neuroprotective, and anticancer, among others. Conclusions of this review on the therapeutic aspects of TQ highlight the medicinal and folk values of this compound against various diseases and ailments. In short, TQ could be a novel drug in clinical trials, as we hope.

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.

The Anti-Leukemic Activity of Natural Compounds

The use of biologically active compounds has become a realistic option for the treatment of malignant tumors due to their cost-effectiveness and safety. In this review, we aimed to highlight the main natural biocompounds that target leukemic cells, assessed by in vitro and in vivo experiments or clinical studies, in order to explore their therapeutic potential in the treatment of leukemia: acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL). It provides a basis for researchers and hematologists in improving basic and clinical research on the development of new alternative therapies in the fight against leukemia, a harmful hematological cancer and the leading cause of death among patients.

Thymoquinone Is a Multitarget Single Epidrug That Inhibits the UHRF1 Protein Complex

Silencing of tumor suppressor genes (TSGs) through epigenetic mechanisms, mainly via abnormal promoter DNA methylation, is considered a main mechanism of tumorigenesis. The abnormal DNA methylation profiles are transmitted from the cancer mother cell to the daughter cells through the involvement of a macromolecular complex in which the ubiquitin-like containing plant homeodomain (PHD), and an interesting new gene (RING) finger domains 1 (UHRF1), play the role of conductor. Indeed, UHRF1 interacts with epigenetic writers, such as DNA methyltransferase 1 (DNMT1), histone methyltransferase G9a, erasers like histone deacetylase 1 (HDAC1), and functions as a hub protein. Thus, targeting UHRF1 and/or its partners is a promising strategy for epigenetic cancer therapy. The natural compound thymoquinone (TQ) exhibits anticancer activities by targeting several cellular signaling pathways, including those involving UHRF1. In this review, we highlight TQ as a potential multitarget single epidrug that functions by targeting the UHRF1/DNMT1/HDAC1/G9a complex. We also speculate on the possibility that TQ might specifically target UHRF1, with subsequent regulatory effects on other partners.

Thymoquinone, as a Novel Therapeutic Candidate of Cancers

To date, natural products are widely used as pharmaceutical agents for many human diseases and cancers. One of the most popular natural products that have been studied for anticancer properties is thymoquinone (TQ). As a bioactive compound of Nigella sativa, TQ has shown anticancer activities through the inhibition of cell proliferation, migration, and invasion. The anticancer efficacy of TQ is being investigated in several human cancers such as pancreatic cancer, breast cancer, colon cancer, hepatic cancer, cervical cancer, and leukemia. Even though TQ induces apoptosis by regulating the expression of pro- apoptotic and anti-apoptotic genes in many cancers, the TQ effect mechanism on such cancers is not yet fully understood. Therefore, the present review has highlighted the TQ effect mechanisms on several signaling pathways and expression of tumor suppressor genes (TSG). Data from relevant published experimental articles on TQ from 2015 to June 2020 were selected by using Google Scholar and PubMed search engines. The present study investigated the effectiveness of TQ alone or in combination with other anticancer therapeutic agents, such as tyrosine kinase inhibitors on cancers, as a future anticancer therapy nominee by using nanotechnology.

Nutritional Value and Preventive Role of Nigella sativa L. and Its Main Component Thymoquinone in Cancer: An Evidenced-Based Review of Preclinical and Clinical Studies

In recent times, scientific attention has been paid to different foods and their bioactive components for the ability to inhibit the onset and progress of different types of cancer. Nigella sativa extract, powder and seed oil and its main components, thymoquinone and α-hederin, have showed potent anticancer and chemosensitizing effects against various types of cancer, such as liver, colon, breast, renal, cervical, lung, ovarian, pancreatic, prostate and skin tumors, through the modulation of various molecular signaling pathways. Herein, the purpose of this review was to highlight the anticancer activity of Nigella sativa and it constitutes, focusing on different in vitro, in vivo and clinical studies and projects, in order to underline their antiproliferative, proapoptotic, cytotoxic and antimetastatic effects. Particular attention has been also given to the synergistic effect of Nigella sativa and it constitutes with chemotherapeutic drugs, and to the synthesized analogs of thymoquinone that seem to enhance the chemo-sensitizing potential. This review could be a useful step towards new research on N. sativa and cancer, to include this plant in the dietary treatments in support to conventional therapies, for the best achievement of therapeutic goals.

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.

Essential Oils from Monarda fistulosa: Chemical Composition and Activation of Transient Receptor Potential A1 (TRPA1) Channels

Little is known about the pharmacological activity of Monarda fistulosa L. essential oils. To address this issue, we isolated essential oils from the flowers and leaves of M. fistulosa and analyzed their chemical composition. We also analyzed the pharmacological effects of M. fistulosa essential oils on transient receptor potential (TRP) channel activity, as these channels are known targets of various essential oil constituents. Flower (MEOFl) and leaf (MEOLv) essential oils were comprised mainly of monoterpenes (43.1% and 21.1%) and oxygenated monoterpenes (54.8% and 77.7%), respectively, with a high abundance of monoterpene hydrocarbons, including p-cymene, γ-terpinene, α-terpinene, and α-thujene. Major oxygenated monoterpenes of MEOFl and MEOLv included carvacrol and thymol. Both MEOFl and MEOLv stimulated a transient increase in intracellular free Ca2+ concentration ([Ca2+]i) in TRPA1 but not in TRPV1 or TRPV4-transfected cells, with MEOLv being much more effective than MEOFl. Furthermore, the pure monoterpenes carvacrol, thymol, and β-myrcene activated TRPA1 but not the TRPV1 or TRPV4 channels, suggesting that these compounds represented the TRPA1-activating components of M. fistulosa essential oils. The transient increase in [Ca2+]i induced by MEOFl/MEOLv, carvacrol, β-myrcene, and thymol in TRPA1-transfected cells was blocked by a selective TRPA1 antagonist, HC-030031. Although carvacrol and thymol have been reported previously to activate the TRPA1 channels, this is the first report to show that β-myrcene is also a TRPA1 channel agonist. Finally, molecular modeling studies showed a substantial similarity between the docking poses of carvacrol, thymol, and β-myrcene in the binding site of human TRPA1. Thus, our results provide a cellular and molecular basis to explain at least part of the therapeutic properties of these essential oils, laying the foundation for prospective pharmacological studies involving TRP ion channels.

Chemopreventive and Anticancer Effects of Thymoquinone: Cellular and Molecular Targets

Thymoquinone (TQ) is a bioactive component derived from the seeds of Nigella sativa that are commonly as black cumin. Evidences indicate that the medicinal properties of TQ have been recognized for more than 2000 years. TQ has been shown to possess potent chemopreventive properties that include anti-inflammatory and anti-neoplastic activities. Recent studies have unraveled the multiple mechanisms through which TQ exerts its chemopreventive and anticancer activity in different cancer cells in a contextual manner. The present review aims to provide a brief compendium on the molecular mechanisms through which TQ inhibits signaling pathways underlying cancer genesis, progression, and metastasis.

Thymoquinone and Difluoromethylornithine (DFMO) Synergistically Induce Apoptosis of Human Acute T Lymphoblastic Leukemia Jurkat Cells Through the Modulation of Epigenetic Pathways

Thymoquinone (TQ), a natural anticancer agent exerts cytotoxic effects on several tumors by targeting multiple pathways, including apoptosis. Difluoromethylornithine (DFMO), an irreversible inhibitor of the ornithine decarboxylase (ODC) enzyme, has shown promising inhibitory activities in many cancers including leukemia by decreasing the biosynthesis of the intracellular polyamines. The present study aimed to investigate the combinatorial cytotoxic effects of TQ and DFMO on human acute T lymphoblastic leukemia Jurkat cells and to determine the underlying mechanisms. Here, we show that the combination of DFMO and TQ significantly reduced cell viability and resulted in significant synergistic effects on apoptosis when compared to either DFMO or TQ alone. RNA-sequencing showed that many key epigenetic players including Ubiquitin-like containing PHD and Ring finger 1 (UHRF1) and its 2 partners DNA methyltransferase 1 (DNMT1) and histone deacetylase 1 (HDAC1) were down-regulated in DFMO-treated Jurkat cells. The combination of DFMO and TQ dramatically decreased the expression of UHRF1, DNMT1 and HDAC1 genes compared to either DFMO or TQ alone. UHRF1 knockdown led to a decrease in Jurkat cell viability. In conclusion, these results suggest that the combination of DFMO and TQ could be a promising new strategy for the treatment of human acute T lymphoblastic leukemia by targeting the epigenetic code.

Thymoquinone synergizes with arsenic and interferon alpha to target human T-cell leukemia/lymphoma

AIMS

To reduce the dose of arsenic used against human T-cell leukemia/lymphoma and to sensitize cells to drug treatment, we combined arsenic/interferon-alpha (As/IFN-α) with thymoquinone (TQ) in HTLV-I positive (HuT-102 and C91) and HTLV-1 negative (CEM and Jurkat) cell lines.

MAIN METHODS

Cells were treated with TQ, As/IFN-α and combinations. Trypan blue and flow cytometry were used to investigate viability and cell cycle effects. Annexin-V staining, rhodamine assay and western blotting were used to determine apoptosis induction and changes in protein expression. Efficacy of single drugs and combinations were tested in adult T-cell leukemia (HuT-102) mouse xenograft model.

KEY FINDINGS

TQ/As/IFN-α led to a more pronounced and synergistic time-dependent inhibitory effect on HTLV-I positive cells in comparison to As/IFN-α. While As/IFN-α combination was not effective against CEM or Jurkat cells, the triple combination TQ/As/IFN-α sensitized these two cell lines and led to a pronounced time-dependent inhibition of cell viability. TQ/As/IFN-α significantly induced apoptosis in all four cell lines and disrupted the mitochondrial membrane potential. Apoptosis was confirmed by the cleavage of caspase 3 and poly (ADP-ribose) polymerase (PARP), downregulation of Bcl-2 and XIAP and upregulation of Bax. TQ alone or in combination activated p53 in HTLV-1 positive cell lines. Strikingly, TQ/As/IFN-α resulted in a pronounced significant decrease in tumor volume in HuT-102 xenograft mouse model, as compared to separate treatments or double combination therapy.

SIGNIFICANCE

Our results suggest a strong potential for TQ to enhance the drug targeting effects of the standard clinical drugs As and IFN-α against CD4+ malignant T-cells.

Extra Virgin Olive Oil and Nigella sativa Oil Produced in Central Italy: A Comparison of the Nutrigenomic Effects of Two Mediterranean Oils in a Low-Grade Inflammation Model

Extra virgin olive (EVO) oil and Nigella sativa (NG) oil are two well-known Mediterranean foods whose consumption has been associated with beneficial effects on human health. This study investigates the nutrigenomic properties of two high quality EVO and NG oils in an in vitro model of low-grade inflammation of human macrophages (THP-1 cells). The aim was to assess whether these healthy foods could modulate inflammation through antioxidant and epigenetic mechanisms. When THP-1 cells were co-exposed to both lipopolysaccharides (LPS)-induced inflammation and oils, both EVO and NG oils displayed anti-inflammatory activity. Both oils were able to restore normal expression levels of DNMT3A and HDAC1 (but not DNMT3B), which were altered under inflammatory conditions. Moreover, EVO oil was able to prevent the increase in TET2 expression and reduce global DNA methylation that were measured in inflamed cells. Due to its antioxidant properties, EVO oil was particularly efficient in restoring normal levels of membrane fluidity, which, on the contrary, were reduced in the presence of inflammation. In conclusion, these data support the hypothesis that these Mediterranean oils could play a major role in the modulation of low-grade inflammation and metabolic syndrome prevention. However, NS oil seems to be more efficient in the control of proinflammatory cytokines, whereas EVO oil better helps to counteract redox imbalance. Further studies that elucidate the nutrigenomic properties of local produce might help to promote regional the production and consumption of high-quality food, which could also help the population to maintain and promote health.

Epigenetic role of thymoquinone: impact on cellular mechanism and cancer therapeutics

Thymoquinone is a natural product known for its anticancer activity. Preclinical studies indicated numerous mechanisms of action by which thymoquinone exerts its effects on cancer cells. Recent evidence has indicated that thymoquinone can modulate epigenetic machinery, like modifying histone acetylation and deacetylation, DNA methylation and demethylation, which are among the major epigenetic changes that can contribute to carcinogenesis. Moreover, thymoquinone can alter the genetic expression of various noncoding RNAs, such as miRNA and lncRNA, which are the key parts of cellular epigenetics. This review focuses on cellular epigenetic systems, epigenetic changes responsible for cancer and the counteraction of thymoquinone to target epigenetic challenges, which might be among the mechanisms of the thymoquinone effect in cancer cells.

Thymoquinone-Induced Reactivation of Tumor Suppressor Genes in Cancer Cells Involves Epigenetic Mechanisms

The epigenetic silencing of tumor suppressor genes (TSGs) is a common finding in several solid and hematological tumors involving various epigenetic readers and writers leading to enhanced cell proliferation and defective apoptosis. Thymoquinone (TQ), the major biologically active compound of black seed oil, has demonstrated anticancer activities in various tumors by targeting several pathways. However, its effects on the epigenetic code of cancer cells are largely unknown. In the present study, we performed RNA sequencing to investigate the anticancer mechanisms of TQ-treated T-cell acute lymphoblastic leukemia cell line (Jurkat cells) and examined gene expression using different tools. We found that many key epigenetic players, including ubiquitin-like containing plant homeodomain (PHD) and really interesting new gene (RING) finger domains 1 (UHRF1), DNMT1,3A,3B, G9A, HDAC1,4,9, KDM1B, and KMT2A,B,C,D,E, were downregulated in TQ-treated Jurkat cells. Interestingly, several TSGs, such as DLC1, PPARG, ST7, FOXO6, TET2, CYP1B1, SALL4, and DDIT3, known to be epigenetically silenced in various tumors, including acute leukemia, were upregulated, along with the upregulation of several downstream pro-apoptotic genes, such as RASL11B, RASD1, GNG3, BAD, and BIK. Data obtained from RNA sequencing were confirmed using quantitative reverse transcription polymerase chain reaction (RT-qPCR) in Jurkat cells, as well as in a human breast cancer cell line (MDA-MB-468 cells). We found that the decrease in cell proliferation and in the expression of UHRF1, DNMT1, G9a, and HDAC1 genes in both cancer cell (Jurkat cells and MDA-MB-468 cells) lines depends on the TQ dose. Our results indicate that the use of TQ as an epigenetic drug represents a promising strategy for epigenetic therapy for both solid and blood tumors by targeting both DNA methylation and histone post-translational modifications.

Synthesis, Biological Evaluation and Docking Studies of Benzoxazoles Derived from Thymoquinone

Thymoquinone (TQ), a natural compound with antimicrobial and antitumor activity, was used as the starting molecule for the preparation of 3-aminothymoquinone (ATQ) from which ten novel benzoxazole derivatives were prepared and characterized by elemental analysis, IR spectroscopy, mass spectrometry and NMR (¹H, ¹³C) spectroscopy in solution. The crystal structure of 4-methyl-2-phenyl-7-isopropyl-1,3-benzoxazole-5-ol (1a) has been determined by X-ray diffraction. All compounds were tested for their antibacterial, antifungal and antitumor activities. TQ and ATQ showed better antibacterial activity against tested Gram-positive and Gram-negative bacterial strains than benzoxazoles. ATQ had the most potent antifungal effect against Candida albicans, Saccharomyces cerevisiae and Aspergillus brasiliensis. Three benzoxazole derivatives and ATQ showed the highest antitumor activities. The most potent was 2-(4-fluorophenyl)-4-methyl-7-isopropyl-1,3-benzoxazole-5-ol (1f). Western blot analyses have shown that this compound inhibited phosphorylation of protein kinase B (Akt) and Insulin-like Growth Factor-1 Receptor (IGF1R β) in HeLa and HepG2 cells. The least toxic compound against normal fibroblast cells, which maintains similar antitumor activities as TQ, was 2-(4-chlorophenyl)-4-methyl-7-isopropyl-1,3-benzoxazole-5-ol (1e). Docking studies indicated that 1e and 1f have significant effects against selected receptors playing important roles in tumour survival.

A dynamic N6-methyladenosine methylome regulates intrinsic and acquired resistance to tyrosine kinase inhibitors

N⁶-methyladenosine (m⁶A) on mRNAs is critical for various biological processes, yet whether m⁶A regulates drug resistance remains unknown. Here we show that developing resistant phenotypes during tyrosine kinase inhibitor (TKI) therapy depends on m⁶A reduction resulting from FTO overexpression in leukemia cells. This deregulated FTO-m⁶A axis pre-exists in naïve cell populations that are genetically homogeneous and is inducible/reversible in response to TKI treatment. Cells with mRNA m⁶A hypomethylation and FTO upregulation demonstrate more TKI tolerance and higher growth rates in mice. Either genetic or pharmacological restoration of m⁶A methylation through FTO deactivation renders resistant cells sensitive to TKIs. Mechanistically, the FTO-dependent m⁶A demethylation enhances mRNA stability of proliferation/survival transcripts bearing m⁶A and subsequently leads to increased protein synthesis. Our findings identify a novel function for the m⁶A methylation in regulating cell fate decision and demonstrate that dynamic m⁶A methylome is an additional epigenetic driver of reversible TKI-tolerance state, providing a mechanistic paradigm for drug resistance in cancer.

Thymoquinone: A novel strategy to combat cancer: A review

The higher consumption of fruit, herbs, spices, and vegetables is well known and practical strategy to cure human cancers owing to their presence of bioactive compounds. Among these, Nigella sativa is a promising source of bioactive compounds including thymoquinone, monoterpenes, p-cymene and α-piene etc. Thymoquinone has been found effective to inhibit the different cancer stages such as proliferation, migration and invasion. It also acts as anticancer agent against different human cancers such as breast, pancreatic, prostate, blood, oral, bone, head and neck, cervical, liver and lung. It significantly mediated miR-34a up-regulation, enhanced the levels of miR-34a through p53, and down controlled Rac1 expression. Thymoquinone induces apoptosis, regulates the levels of pro- and anti- apoptotic genes. It also has been known to lower the phosphorylation of NF-κB and IKKα/β and reduces the metastasis as well as also lowered the ERK1/2 and PI3K activities. Thymoquinone inhibits the metastasis through activation of JNK and p38. The present review article highlights the anticancer perspectives of thymoquinone in human by various pathways and use of this compound as diet based therapy has proven new pharmacological agent against several types of cancers.