Androgen receptor and E2F-1 targeted thymoquinone therapy for hormone-refractory prostate cancer

Structure-based investigation of pyruvate dehydrogenase kinase-3 inhibitory potential of thymoquinone, targeting lung cancer therapy

Protein kinases are an attractive therapeutic target for cardiovascular, cancer and neurodegenerative diseases. Cancer cells demand energy generation through aerobic glycolysis, surpassing "oxidative phosphorylation" (OXPHOS) in mitochondria. The pyruvate dehydrogenase kinases (PDKs) have many regulatory roles in energy generation balance by controlling the pyruvate dehydrogenase complex. Overexpression of PDKs is associated with the overall survival of cancer. PDK3, an isoform of PDK is highly expressed in various cancer types, is targeted for inhibition in this study. PDK3 has been shown to binds strongly with a natural compound, thymoquinone (TQ), which is known to exhibit anti-cancer potential. Detailed interaction between the PDK3 and TQ was carried out using spectroscopic and docking methods. The overall changes in the protein's structures after TQ binding were estimated by UV-Vis spectroscopy, circular dichroism and fluorescence binding studies. The kinase activity assay was also carried out to see the kinase inhibitory potential of TQ. The enzyme inhibition assay suggested an excellent inhibitory potential of TQ towards PDK3 (IC50 = 5.49 μM). We observed that TQ forms a stable complex with PDK3 without altering its structure and can be a potent PDK3 inhibitor which may be implicated in cancer therapy after desired clinical validation.

Thymoquinone-loaded lipid nanocapsules with promising anticancer activity for colorectal cancer

Colorectal cancer (CRC) is the third most common worldwide. Depending on its stage, chemotherapy is usually given after surgery when CRC has already metastasized to other organs like the liver or lungs. Unfortunately, the current antineoplastics used for CRC therapies involve toxicity and side effects due to their lack of site-specificity. To overcome the drawbacks of heavy chemotherapy, this study proposes to assess the efficacy of thymoquinone (TQ), a bioactive constituent of black seeds (Nigella sativa), as an antiproliferative and pro-apoptotic agent on an experimental CRC model in mice. TQ was encapsulated in lipid nanocapsules (LNCs), used as nanocarriers, in order to increase its specificity and cell absorption. TQ-loaded LNCs (TQ-LNCs) have a diameter of 58.3 ± 3.7 nm and 87.7 ± 4.5% TQ encapsulation efficiency. In turn, in vivo studies showed that the intratumoral administration of TQ-LNCs decreased the tumor size in colorectal cancer bearing mice compared to the control group. TQ-LNCs were more effective than free TQ for inducing tumor cell death. These results highlight the potential of TQ entrapped in LNCs as an anticancer agent for CRC treatment.

Anticancer activity of thymoquinone against breast cancer cells: Mechanisms of action and delivery approaches

The rising incidence of breast cancer has been a significant source of concern in the medical community. Regarding the adverse effects and consequences of current treatments, cancers' health, and socio-economical aspects have become more complicated, leaving research aimed at improved or new treatments on top priority. Medicinal herbs contain multitarget compounds that can control cancer development and advancement. Owing to Nigella Sativa's elements, it can treat many disorders. Thymoquinone (TQ) is a natural chemical derived from the black seeds of Nigella sativa Linn proved to have anti-cancer and anti-inflammatory properties. TQ interferes in a broad spectrum of tumorigenic procedures and inhibits carcinogenesis, malignant development, invasion, migration, and angiogenesis owing to its multitargeting ability. It effectively facilitates miR-34a up-regulation, regulates the p53-dependent pathway, and suppresses Rac1 expression. TQ promotes apoptosis and controls the expression of pro- and anti-apoptotic genes. It has also been shown to diminish the phosphorylation of NF-B and IKK and decrease the metastasis and ERK1/2 and PI3K activity. We discuss TQ's cytotoxic effects for breast cancer treatment with a deep look at the relevant stimulatory or inhibitory signaling pathways. This review discusses the various forms of polymeric and non-polymeric nanocarriers (NC) and the encapsulation of TQ for increasing oral bioavailability and enhanced in vitro and in vivo efficacy of TQ-combined treatment with different chemotherapeutic agents against various breast cancer cell lines. This study can be useful to a broad scientific community, comprising pharmaceutical and biological scientists, as well as clinical investigators.

Antioxidant Thymoquinone and Its Potential in the Treatment of Neurological Diseases

Oxidative stress is one of the main pathogenic factors of neuron damage in neurodegenerative processes; this makes it an important therapeutic target to which the action of neuroprotectors should be directed. One of these drugs is thymoquinone. According to modern data, this substance has a wide range of pharmacological activity, including neuroprotective, which was demonstrated in experimental modeling of various neurodegenerative diseases and pathological conditions of the brain. The neuroprotective effect of thymoquinone is largely due to its antioxidant ability. Currently available data show that thymoquinone is an effective means to reduce the negative consequences of acute and chronic forms of cerebral pathology, leading to the normalization of the content of antioxidant enzymes and preventing an increase in the level of lipid peroxidation products. Antioxidant properties make this substance a promising basis for the development of prototypes of therapeutic agents aimed at the treatment of a number of degenerative diseases of the central nervous system.

Mitochondrial Dysfunction and Induction of Apoptosis in Hepatocellular Carcinoma and Cholangiocarcinoma Cell Lines by Thymoquinone

Thymoquinone (TQ), a plant-based bioactive constituent derived from the volatile oil of Nigella sativa, has been shown to possess some anti-neoplastic activities. The present study aimed to investigate the mitochondria and apoptosis observed when TQ is applied against hepatocellular carcinoma (HepG2) and cholangiocarcinoma (HuCCT1) cells, two of the most common primary tumors of the liver. All cell lines were treated with increasing concentrations of TQ for varying durations. The anti-proliferative effect of TQ was measured using the methoxyphenyl-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and resulted in dose- and time-dependent growth inhibition in both cell lines. Cell cycle, apoptosis, and assessment of mitochondria viability by morphology assessment and evaluation of the mitochondrial membrane potential were investigated. The present study confirms that TQ caused cell cycle arrest at different phases and induced apoptosis in both cell lines. A systematic review of rodent animal models was also carried out. Overall, our data seem to represent the most robust results, suggesting that TQ possesses promising therapeutic potential as an anti-tumor agent for the treatment of hepatocellular carcinoma and cholangiocarcinoma.

Phytochemicals in Inhibition of Prostate Cancer: Evidence from Molecular Mechanisms Studies

Prostate cancer is one of the leading causes of death for men worldwide. The development of resistance, toxicity, and side effects of conventional therapies have made prostate cancer treatment become more intensive and aggressive. Many phytochemicals isolated from plants have shown to be tumor cytotoxic. In vitro laboratory studies have revealed that natural compounds can affect cancer cell proliferation by modulating many crucial cellular signaling pathways frequently dysregulated in prostate cancer. A multitude of natural compounds have been found to induce cell cycle arrest, promote apoptosis, inhibit cancer cell growth, and suppress angiogenesis. In addition, combinatorial use of natural compounds with hormone and/or chemotherapeutic drugs seems to be a promising strategy to enhance the therapeutic effect in a less toxic manner, as suggested by pre-clinical studies. In this context, we systematically reviewed the currently available literature of naturally occurring compounds isolated from vegetables, fruits, teas, and herbs, with their relevant mechanisms of action in prostate cancer. As there is increasing data on how phytochemicals interfere with diverse molecular pathways in prostate cancer, this review discusses and emphasizes the implicated molecular pathways of cell proliferation, cell cycle control, apoptosis, and autophagy as important processes that control tumor angiogenesis, invasion, and metastasis. In conclusion, the elucidation of the natural compounds' chemical structure-based anti-cancer mechanisms will facilitate drug development and the optimization of drug combinations. Phytochemicals, as anti-cancer agents in the treatment of prostate cancer, can have significant health benefits for humans.

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 Alterations of the Apoptotic Gene Expressions and Cell Cycle Arrest in Genetically Distinct Triple-Negative Breast Cancer Cells

Breast cancer (BC) is the most common cancer in women worldwide, and it is one of the leading causes of cancer death in women. triple-negative breast Cancer (TNBC), a subtype of BC, is typically associated with the highest pathogenic grade and incidence in premenopausal and young African American (AA) women. Chemotherapy, the most common treatment for TNBC today, can lead to acquired resistance and ineffective treatment. Therefore, novel therapeutic approaches are needed to combat medication resistance and ineffectiveness in TNBC patients. Thymoquinone (TQ) is shown to have a cytotoxic effect on human cancer cells in vitro. However, TQ's mode of action and precise mechanism in TNBC disease in vitro have not been adequately investigated. Therefore, TQ's effects on the genetically different MDA-MB-468 and MDA-MB-231 human breast cancer cell lines were assessed. The data obtained show that TQ displayed cytotoxic effects on MDA-MB-468 and MDA-MB-231 cells in a time- and concentration-dependent manner after 24 h, with IC50 values of 25.37 µM and 27.39 µM, respectively. Moreover, MDA-MB-231 and MDA-MB-468 cells in a scratched wound-healing assay displayed poor wound closure, inhibiting invasion and migration via cell cycle blocking after 24 h. TQ arrested the cell cycle phase in MDA-MB-231 and MDA-MB-468 cells. The three cell cycle stages in MDA-MB-468 cells were significantly affected at 15 and 20 µM for G0/G1 and S phases, as well as all TQ concentrations for G2/M phases. In MDA-MB-468 cells, there was a significant decrease in G0/G1 phases with a substantial increase in the S phase and G2/M phases. In contrast, MDA-MB-231 showed a significant effect only during the two cell cycle stages (S and G2/M), at concentrations of 15 and 20 µM for S phases and all TQ values for G2/M phases. The TQ effect on the apoptotic gene profiles indicated that TQ upregulated 15 apoptotic genes in MDA-MB-231 TNBC cells, including caspases, GADD45A, TP53, DFFA, DIABLO, BNIP3, TRAF2/3, and TNFRSF10A. In MDA-MB-468 cells, 16 apoptotic genes were upregulated, including TNFRSF10A, TNF, TNFRSF11B, FADD TNFRSF10B, CASP2, and TRAF2, all of which are important for the apoptotic pathway andsuppress the expression of one anti-apoptotic gene, BIRC5, in MDA-MB-231 cells. Compared to MDA-MB-231 cells, elevated levels of TNF and their receptor proteins may contribute to their increased sensitivity to TQ-induced apoptosis. It was concluded from this study that TQ targets the MDA-MB-231 and MDA-MB-468 cells differently. Additionally, due to the aggressive nature of TNBC and the lack of specific therapies in chemoresistant TNBC, our findings related to the identified apoptotic gene profile may point to TQ as a potential agent for TNBC therapy.

Combinatorial effect of thymoquinone with chemo agents for tumor therapy

BACKGROUND

Most chemotherapeutics used in cancer therapies exhibit considerable side effects to the patients. Thus, developing new chemo agents to treat cancer patients with minimal toxic and side effects is urgently needed. Recently, the combination of different chemotherapeutics has become a promising strategy to treat malignancies. Thymoquinone (TQ) is a primary bioactive compound derived from the folk medicinal plant Nigella sativa, which has been found an antitumor, chemopreventive and chemopotentiating agent against human neoplastic diseases.

PURPOSE

We briefly summarize the current research of the biomolecular mechanisms of TQ and evaluate the existing literature on TQ adjuvant therapies against various cancers.

METHOD

The data in this review were gathered by several search engines including, Google Scholar, PubMed and ScienceDirect. We highlighted and classified the outcomes of both in vitro and in vivo experiments of TQ adjuvant therapies against human cancers and their chemopreventive activities on vital organs.

RESULTS

Several studies have shown that TQ synergistically potentiated the antitumor activity of numerous chemo agents against human neoplastic disease, including lung, breast, liver, colorectal, skin, prostate, stomach, bone and blood cancers. TQ also acted as a chemopreventive agent and reduced the toxicity of many chemo agents to vital organs, such as the heart, liver, kidneys and lungs.

CONCLUSION

In summary, we highly recommend an advanced evaluation of TQ adjuvant therapies at the level of preclinical and clinical trials, which could lead to a novel combinatorial therapy for cancer treatment with low or tolerable adverse effects on patients.

Potential anticancer properties and mechanisms of thymoquinone in osteosarcoma and bone metastasis

Despite great advances, therapeutic approaches of osteosarcoma, the most prevalent class of preliminary pediatric bone tumors, as well as bone-related malignancies, continue to demonstrate insufficient adequacy. In recent years, a growing trend toward applying natural bioactive compounds, particularly phytochemicals, as novel agents for cancer treatment has been observed. Bioactive phytochemicals exert their anticancer features through two main ways: they induce cytotoxic effects against cancerous cells without having any detrimental impact on normal cell macromolecules such as DNA and enzymes, while at the same time combating the oncogenic signaling axis activated in tumor cells. Thymoquinone (TQ), the most abundant bioactive compound of Nigella sativa, has received considerable attention in cancer treatment owing to its distinctive properties, including apoptosis induction, cell cycle arrest, angiogenesis and metastasis inhibition, and reactive oxygen species (ROS) generation, along with inducing immune system responses and reducing side effects of traditional chemotherapeutic drugs. The present review is focused on the characteristics and mechanisms by which TQ exerts its cytotoxic effects on bone malignancies.

Evaluation of Portable Vibrational Spectroscopy Sensors as a Tool to Detect Black Cumin Oil Adulteration

Black cumin oil adulteration has become a concern because it has numerous health benefits and a high price. Therefore, a simple, non-destructive, and rapid method to identify adulterations in black seed oil is necessary to protect the quality of the oils. This study aimed to perform a non-invasive method to authenticate black cumin oil by portable FT-NIR, FT-MIR, and Raman spectrometers. Spectra were collected with portable devices and analyzed using Soft Independent Modelling of Class Analogy (SIMCA) to generate a classification model to identify pure black cumin oil and partial least squares regression (PLSR) to predict the adulterant levels. For confirmation, the fatty acid profile of the oils was determined by gas chromatography (GC). SIMCA and PLSR models provided a very high performance in detecting adulterated samples in all portable units. These portable units showed great potential for rapid and non-destructive monitoring to identify adulterated black cumin oils.

PI3K-AKT Pathway Modulation by Thymoquinone Limits Tumor Growth and Glycolytic Metabolism in Colorectal Cancer

Colorectal cancer (CRC) is the third leading cause of death in men and the fourth in women worldwide and is characterized by deranged cellular energetics. Thymoquinone, an active component from Nigella sativa, has been extensively studied against cancer, however, its role in affecting deregulated cancer metabolism is largely unknown. Further, the phosphoinositide 3-kinase (PI3K) pathway is one of the most activated pathways in cancer and its activation is central to most deregulated metabolic pathways for supporting the anabolic needs of growing cancer cells. Herein, we provide evidence that thymoquinone inhibits glycolytic metabolism (Warburg effect) in colorectal cancer cell lines. Further, we show that such an abrogation of deranged cell metabolism was due, at least in part, to the inhibition of the rate-limiting glycolytic enzyme, Hexokinase 2 (HK2), via modulating the PI3/AKT axis. While overexpression of HK2 showed that it is essential for fueling glycolytic metabolism as well as sustaining tumorigenicity, its pharmacologic and/or genetic inhibition led to a reduction in the observed effects. The results decipher HK2 mediated inhibitory effects of thymoquinone in modulating its glycolytic metabolism and antitumor effects. In conclusion, we provide evidence of metabolic perturbation by thymoquinone in CRC cells, highlighting its potential to be used/repurposed as an antimetabolite drug, though the latter needs further validation utilizing other suitable cell and/or preclinical animal models.

Herceptin-conjugated magnetic polystyrene-Agsbox nanoparticles as a theranostic agent for breast cancer

Breast cancer is a malignant tumor, which has derived from cells of the breast. Further, a relatively rapid metastasis, and resistance development against all the conventional drug combinations are major clinical issues in breast cancer patients as well as limitations like toxicity, genetic mutation, and metastasis make difficult the use of conventional therapy methods such as chemotherapy, radiotherapy, and local surgery. Therefore, considering the urgent needs, and high death rate in breast cancer cases, the development of new diagnosis and treatment regimens which diagnosed at the early stage and protected normal tissues required for clinical applications. Recently, the combination of tumor diagnosis and treatment within a single platform is a novel perspective, and magnetic nanoparticles are potential candidate owing to their low toxic effect, biocompatibility, biological degradability, superior magnetic properties, and targeting ability to overcome the problems of conventional diagnosis and therapy techniques. Considering these restrictions and requirements, the goal of this research was to investigate the potential of an innovative theranostic agent, which is soybean oil-based polystyrene (PS)-g-soybean oil graft copolymer containing AgNPs (PS-Agsbox) for treatment and MRI-based diagnosis of cancer. Herein, we designed targeted magnetic PS-Agsbox nanoparticles carrying thymoquinone (TQ) that is known for its anticancer potential against breast cancer, and herceptin (HER), which is to bind to the HER2 receptor protein on the surface of HER2-positive tumor cells, and acts by blocking the effects of it. We have successfully demonstrated selective binding, effective uptake of HER-conjugated magnetic PS-Agsbox nanoparticles into MDA-MB-231 (human breast carcinoma cells, a HER2-underexpressing cell line) and SKBR-3 (human breast cancer cells, a HER2-overexpressing breast cancer cell line) cell lines while no effect against L929 (mouse fibroblast cell line). Moreover, the magnetic resonance (MRI) properties of HER-conjugated magnetic PS-Agsbox nanoparticles were also confirmed.

Triangulating the pharmacological properties of thymoquinone in regulating reactive oxygen species, inflammation, and cancer: Therapeutic applications and mechanistic pathways

Cancer is a heterogeneous disease with high morbidity and mortality rate involving changes in redox balance and deregulation of redox signalling. For decades, studies have involved developing an effective cancer treatment to combat treatment resistance. As natural products such as thymoquinone have numerous health benefits, studies are also focusing on using them as a viable method for cancer treatment, as they have minimal toxic effects compared with standard cancer treatments. Thymoquinone studies have shown numerous mechanisms of action, such as regulation of reactive species interfering with DNA structure, modulating various potential targets and their signalling pathways as well as immunomodulatory effects in vitro and in vivo. Thymoquinone's anti-cancer effect is mainly due to the induction of apoptotic mechanisms, such as activation of caspases, downregulation of precancerous genes, inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), anti-tumour cell proliferation, ROS regulation, hypoxia and anti-metastasis. Insight into thymoquinone's potential as an alternative treatment for chemoprevention and inflammation can be accomplished via compiling these studies, to provide a better understanding on how and why it works, as well as its interactions with common chemotherapeutic treatments.

Prognostic Value of E2F Transcription Factor Expression in Pancreatic Adenocarcinoma

Background

Pancreatic adenocarcinoma (PAAD) is one of the deadliest types of cancer. In the early stages, patients often have atypical symptoms, making diagnosis difficult. The prognosis of diagnosed patients is very poor and treating PAAD is challenging. Therefore, determining reliable risk factors related to PAAD development is critical for improving patient prognosis. E2F family transcription factors (TFs) are essential regulators of DNA synthesis and cell cycle progression in eukaryotic cells, and they have been identified as prognostic biomarkers associated with multiple cancer types. However, further research is necessary to establish the prognostic relevance of these TFs in PAAD patients.

Material/Methods

We assessed PAAD patient transcriptional and outcome data using the TIMER, ONCOMINE, STRING, GEPIA, cBioPortal, Kaplan-Meier Plotter, GSCALite, and starBase databases.

Results

PAAD tumor tissues exhibited increased expression of E2F1/3/5/7/8 relative to that in normal tissues, while the expression of E2F2/3/6/8 was associated with a more advanced tumor stage. Survival analyses indicated that PAAD patients expressing higher levels of E2F1/2/3/7/8 exhibited shorter overall survival (OS) and disease-free survival (DFS) than patients expressing lower levels of these TFs. In addition, E2F4 and E2F6 overexpression was associated with poorer DFS and OS, respectively. We also found that the expression of E2Fs was significantly correlated with immune infiltrates, including CD8+ T cells, CD4+ T cells, B cells, dendritic cells, neutrophils, and macrophages.

Conclusions

Our study may provide new insights into the optimal choice of immunotherapy and promising novel targets for therapeutic intervention in PAAD patients.

Radioresistance of Human Cancers: Clinical Implications of Genetic Expression Signatures

Although radiotherapy is given to more than 50% of cancer patients, little progress has been made in identifying optimal radiotherapy - drug combinations to improve treatment efficacy. Using molecular data from The Cancer Genome Atlas (TCGA), we extracted a total of 1016 cancer patients that received radiotherapy. The patients were diagnosed with head-and-neck (HNSC - 294 patients), cervical (CESC - 166 patients) and breast (BRCA - 549 patients) cancer. We analyzed mRNA expression patterns of 50 hallmark gene sets of the MSigDB collection, which we divided in eight categories based on a shared biological or functional process. Tumor samples were split into upregulated, neutral or downregulated mRNA expression for all gene sets using a gene set analysis (GSEA) pre-ranked analysis and assessed for their clinical relevance. We found a prognostic association between three of the eight gene set categories (Radiobiological, Metabolism and Proliferation) and overall survival in all three cancer types. Furthermore, multiple single associations were revealed in the other categories considered. To the best of our knowledge, our study is the first report suggesting clinical relevance of molecular characterization based on hallmark gene sets to refine radiation strategies.

TQFL12, a novel synthetic derivative of TQ, inhibits triple-negative breast cancer metastasis and invasion through activating AMPK/ACC pathway

Thymoquinone (TQ) has been reported as an anti‐tumour drug widely studied in various tumours, and its mechanism and effect of which has become a focus of current research. However, previous studies from our laboratory and other groups found that TQ showed weak anti‐tumour effects in many cancer cell lines and animal models. Therefore, it is necessary to modify and optimize the structure of TQ to obtain new chemical entities with high efficiency and low toxicity as candidates for development of new drugs in treating cancer. Therefore, we designed and synthesized several TQ derivatives. Systematic analysis, including in vitro and in vivo, was conducted on a panel of triple‐negative breast cancer (TNBC) cells and mouse model to demonstrate whether TQFL12, a new TQ derivative, is more efficient than TQ. We found that the anti‐proliferative effect of TQFL12 against TNBC cells is significantly stronger than TQ. We also demonstrated TQFL12 affects different aspects in breast cancer development including cell proliferation, migration, invasion and apoptosis. Moreover, TQFL12 inhibited tumour growth and metastasis in cancer cell–derived xenograft mouse model, with less toxicity compared with TQ. Finally, mechanism research indicated that TQFL12 increased AMPK/ACC activity by stabilizing AMPKα, while molecular docking supported the direct interaction between TQFL12 and AMPKα. Taken together, our findings suggest that TQFL12, as a novel chemical entity, possesses a better inhibitory effect on TNBC cells and less toxicity in both in vitro and in vivo studies. As such, TQFL12 could serve as a potential therapeutic agent for breast cancer.

Nigella sativa extract kills pre-malignant and malignant oral squamous cell carcinoma cells

In this study, the potential of Nigella sativa was evaluated in the management of oral cancer through assays designed to mimic conditions expected when chewing the whole seeds or use of a seed extract. For this purpose, a water-based extract of N. sativa seeds was prepared, mimicking the chewing process. This extract demonstrated significant cytotoxic effect on oral cancer and pre-cancerous leukoplakia cells in vitro at a much lower concentration than the predicted oral concentration that could be achieved upon seed chewing. When the active constituent(s) in this water-based N. sativa seed extract, was explored significant quantities of the compound α-hederin was detected but only modest quantities of thymoquinone suggesting that thymoquinone is not fully released into the aqueous medium during the chewing process. While the N. sativa seed extract induced a different effect on the cells than that of pure thymoquinone, α-hederin alone induced a very similar effect on the cells to that of the extract. These results suggest that α-hederin and not thymoquinone, is the major component of the seed that is responsible for the inhibitory effect observed in vitro. Therefore, chewing N. sativa whole seeds or applying a concentrated extract on the oral lesions may be an inexpensive, widely available, and effective option for patients at risk of developing oral cancer who are receiving no other preventive treatment.

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.

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.

Establishment of Novel Prostate Cancer Risk Subtypes and A Twelve-Gene Prognostic Model

Prostate cancer (PCa) is the most common malignancy among men worldwide. However, its complex heterogeneity makes treatment challenging. In this study, we aimed to identify PCa subtypes and a gene signature associated with PCa prognosis. In particular, nine PCa-related pathways were evaluated in patients with PCa by a single-sample gene set enrichment analysis (ssGSEA) and an unsupervised clustering analysis (i.e., consensus clustering). We identified three subtypes with differences in prognosis (Risk_H, Risk_M, and Risk_L). Differences in the proliferation status, frequencies of known subtypes, tumor purity, immune cell composition, and genomic and transcriptomic profiles among the three subtypes were explored based on The Cancer Genome Atlas database. Our results clearly revealed that the Risk_H subtype was associated with the worst prognosis. By a weighted correlation network analysis of genes related to the Risk_H subtype and least absolute shrinkage and selection operator, we developed a 12-gene risk-predicting model. We further validated its accuracy using three public datasets. Effective drugs for high-risk patients identified using the model were predicted. The novel PCa subtypes and prognostic model developed in this study may improve clinical decision-making.

Anti-inflammatory effects of thymoquinone and its protective effects against several diseases

Thymoquinone (TQ, 2-methyl-5-isopropyl-1, 4-benzoquinone), a monoterpene molecule present in Nigella sativa L., has an anti-inflammatory, anti-oxidant, and anti-apoptotic properties in several disorders such as asthma, hypertension, diabetes, inflammation, bronchitis, headache, eczema, fever, dizziness and influenza. TQ exerts its anti-inflammatory and anti-oxidant effects via several molecular pathways, including the release of cytokines, and activation of cyclooxygenase-2 (COX2), nuclear factor erythroid 2-related factor 2 (Nrf2), phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT), nuclear factor kappa-light-chain-enhancer of activated B (NF-Κβ). In this review, recent reports on the anti-inflammatory efficacy of TQ in heart disorders, respiratory diseases, neuroinflammation, diabetes and arthritis are summarized. We suggest that further investigation is necessary to better characterize the efficacy of TQ as a therapeutic agent.

Senescent Colon and Breast Cancer Cells Induced by Doxorubicin Exhibit Enhanced Sensitivity to Curcumin, Caffeine, and Thymoquinone

Cellular senescence is a process of physiological growth arrest that can be induced by intrinsic or extrinsic stress signals. Some cancer therapies are associated with senescence of cancer cells with a typical cell cycle arrest. Doxorubicin (Dox) induces senescence by a p53-dependent pathway and telomere dysfunction of numerous cancers. However, cellular senescence induces suppression in proliferation activity, and these cells will remain metabolically active and play an important role in tumor relapse and development of drug resistance. In the current study, we investigated the apoptotic effect of curcumin (Cur), caffeine (Caff), and thymoquinone (TQ) on senescent colon cancer HCT116 and breast cancer MCF7 cell lines treated with Dox. Results showed typical senescence markers including decreased bromodeoxyuridine incorporation, increased accumulation of senescence-associated β-galactosidase (SA-β-gal), cell cycle arrest, and upregulation of p53, P-p53, and p21 proteins. Annexin-V analysis by flow cytometry revealed 2- to 6-fold increases in annexin-V–positive cells in Dox-treated MCF7 and HCT116 cells by Cur (15 µM), Caff (10 mM), and TQ (50 µM; P < .001). In comparison between proliferative and senescent of either HCT116 or MCF7 cells, Caff at 15 mM and TQ at 25 µM induced significant increases in apoptosis of Dox-treated cells compared with proliferative cells (P < .001). Data revealed that Cur, Caff, and TQ potentially induced apoptosis of both proliferative and senescent HCT116 and MCF7 cells. In vivo and clinical trials are of great importance to validate this result.

Antibacterial Activity and Time-kill Assay of Terminalia catappa L. and Nigella sativa L. against Selected Human Pathogenic Bacteria

The current investigation aims to test the susceptibility of human pathogenic clinical isolates and MTCC strains to leaf and seed extracts of Terminalia catappa and Nigella sativa. Disc diffusion assay, micro dilution assay and minimum Bactericidal Concentration investigated the susceptibility of bacteria to the test extracts. The active extract was subjected to phytochemical screening, separation of the phytochemicals by Thin Layer Chromatography, bioactivity guided assay and Time- kill assay. Acetone and methanol extracts of T.catappa revealed, significant inhibition of clinical origin Staphylococcus aureus followed by Proteus vulgaris and the MTCC strains Staphylococcus aureus, Salmonella typhi, Pseudomonas aeroginosa and Bacillus subtilis. Nigella sativa inhibited the growth of clinical origin Staph.aureus and MTCC strain of Staph.aureus, Salmonella typhi and B.subtilis. Minimum inhibitory concentration for all the test bacteria was reported in the range of 5000μg/ml to 9 μg/ml in T. catappa extract. Most sensitive being the clinical isolate Staph. aureus and Proteus vulgaris. The bactericidal concentration for the test bacteria was found to be between 5000μg/ml and 625μg/ml. Phyto-chemical analysis of leaf extracts of T. catappa found to have dominated by polyphenols (Terpenoids, steroids, flavonoids, flavones, saponins and tannins) and N.sativa extracts recorded the presence of alkaloids, proteins and oils and fats. TLC profiling of the acetone extract revealed many antibacterial active bands. Bands having Retention factor 0.47 and 0.52 were active against the test bacteria. Time kill assay of the acetone extract of T. catappa were carried out for the first time. The extract exhibited dose dependent bactericidal and bacteriostatic activity against the clinical isolates.

Investigation of cellular effects of thymoquinone on glioma cell

Glioblastoma, as an invasive tumor, is one of the most common primary malignant brain tumors. Despite maximum aggressive treatment, patients with glioblastoma have a dismal prognosis. Thymoquinone (TQ) has been found to show anti-cancer effects on different types of cancer. There are a few in vitro studies on the effect of TQ on glial tumors. However, the molecular mechanism of TQ's anti-cancer effect has not been fully elucidated. In the present study, we aimed to investigate the genotoxic, apoptotic, and cytotoxic effects of TQ on C6 rat glioma cells. C6 glioma cells were analyzed after 24 h of exposure to different concentrations of TQ by the ATP cell viability assay for cytotoxicity, comet assay for genotoxicity, 2',7'dichlorodihydrofluorescein diacetate (H2DCF-DA) for intracellular reactive oxygen species (iROS) generation, 3.3'dihexyloxacarbocyanine iodide (DiOC6(3)) for mitochondrial membrane potential, GSH/GSSG-Glo Assay for glutathione level and Fura-2AM for intracellular calcium levels. Apoptosis induction was studied by acridine orange/ethidium bromide double staining, flow cytometry, and western blotting analyses. Caspase-3, Caspase-9, Bax, Bcl-2, and pSTAT3 protein levels were determined by the western blotting method. Cytotoxicity was enhanced by TQ in C6 glioma cells in a concentration-dependent manner. TQ also induced DNA damage, apoptosis, and increased iROS. Also, MMP and GSH levels were decreased by TQ. It inhibited pSTAT3, resulting in apoptosis induction through the regulation of anti-apoptotic and pro-apoptotic proteins. Our results suggest that TQ would be an effective treatment in glioma. Further studies should support these findings.

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.

Targeting kinases with thymoquinone: a molecular approach to cancer therapeutics

Kinases are enzymes that are important for cellular functions, but their overexpression has strong connections with carcinogenesis, rendering them important targets for anticancer drugs. Thymoquinone (TQ) is a natural compound with proven anticancer activities, at least in preclinical studies. TQ can target several kinases, including phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase (MAPK), Janus kinase/signal transducers and activators of transcription (JAK/STAT), polo-like kinase 1 (PLK1), and tyrosine kinase in different cancer cells and animal models. Inhibiting the activity of kinases or suppressing their expression might be among the mechanisms of TQ anticancer activity. In this review, we discuss the role of TQ in kinase regulation in different cancer models.

Current opinion and mechanistic interpretation of combination therapy for castration-resistant prostate cancer

Recent advances in genomics technology have led to the massive discovery of new drug targets for prostate cancer; however, none of the currently available therapeutics is curative. One of the greatest challenges is drug resistance. Combinations of therapies with distinct mechanisms of action represent a promising strategy that has received renewed attention in recent years. Combination therapies exert cancer killing functions through either concomitant targeting of multiple pro-cancer factors or more effective inhibition of a single pathway. Theoretically, the combination therapy can improve efficacy and efficiency compared with monotherapy. Although increasing numbers of drug combinations are currently being tested in clinical trials, the mechanisms by which these combinations can overcome drug resistance have yet to be fully understood. The purpose of this review is to summarize recent work on therapeutic combinations in the treatment of castration-resistant prostate cancer and discuss emerging mechanisms underlying drug resistance. In addition, we provide an overview of the current preclinical mechanistic studies on potential therapeutic combinations to overcome drug resistance.

Thymoquinone as a Potential Neuroprotector in Acute and Chronic Forms of Cerebral Pathology

Thymoquinone is one of the main active components of the essential oil from black cumin (Nigella sativa) seeds. Thymoquinone exhibits a wide range of pharmacological activities, including neuroprotective action demonstrated in the models of brain ischemia/reperfusion, Alzheimer's and Parkinson's diseases, and traumatic brain injury. The neuroprotective effect of thymoquinone is mediated via inhibition of lipid peroxidation, downregulation of proinflammatory cytokines, maintenance of mitochondrial membrane potential, and prevention of apoptosis through inhibition of caspases-3, -8, and -9. Thymoquinone-based mitochondria-targeted antioxidants are accumulated in the mitochondria and exhibit neuroprotective properties in nanomolar concentrations. Thymoquinone reduces the negative effects of acute and chronic forms of brain pathologies. The mechanisms of the pharmacological action of thymoquinone and its chemical derivatives require more comprehensive studying. In this paper, we formulated the prospects of application of thymoquinone and thymoquinone-based drugs in the therapy of neurodegenerative diseases.

Low Doses of Thymoquinone and Ferulic Acid in Combination Effectively Inhibit Proliferation of Cultured MDA-MB 231 Breast Adenocarcinoma Cells

Thymoquinone (TQ) and Ferulic Acid (FA) are natural ingredients from Nigella sativa and Ferula asafetida, respectively. Individually both TQ and FA have shown anticancer properties in a variety of cancer cell lines. We investigated the combination effect of lower doses of TQ and FA on proliferation, apoptosis, and cell cycle of a breast cancer cell line MDA-MB 231. Cells were treated with various concentrations of TQ, FA and various combinations of TQ + FA for 48 hrs. Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, whereas cell cycle and apoptosis were measured with flow-cytometry after propidium iodide staining and Annexin-V/FITC staining, respectively. TQ (50 and 100 µM) and FA (450 µM), and all the doses of TQ and FA in combination significantly decreased cell proliferation. 25 µM TQ and 250 µM FA individually did not affect cell proliferation but in combination significantly reduced cell proliferation. TQ at 50 µM caused significant apoptosis, whereas, FA did not affect apoptosis. These in vitro data suggest that in combination, relatively lower doses of TQ and FA are effective in decreasing cancer cell proliferation, and thus have anticancer therapeutic potential. Further research is needed to corroborate these findings in an animal model of breast cancer.

Thymoquinone protection against 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin induced nephrotoxicity in rats

We investigated the effects of thymoquinone (TQ) on kidney tissues of Wistar rats with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced nephrotoxicity. We used 50 rats divided into five groups; control, corn oil, TCDD, TQ, TCDD + TQ. We found that malondialdehyde (MDA), total oxidant status (TOS), blood urea nitrogen (BUN), creatinine, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) levels in the TCDD treated group increased significantly compared to the other groups, while reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant status (TAS) levels decreased in the TCDD group. In the TQ treated group, we found that GSH, SOD, CAT, TAS levels increased and MDA, TOS, IL-6 and TNF-α levels decreased compared to the other groups. The effects of TCDD on oxidative stress parameters, inflammatory markers and histological changes were ameliorated by TQ treatment.

Nanocarriers: more than tour de force for thymoquinone

Introduction: Thymoquinone (TQ), 2-isopropyl-5-methylbenzo-1, 4-quinone, the main active constituent of Nigella sativa (NS) plant, has been proven to be of great therapeutic aid in various in vitro and in vivo conditions. Despite the promising therapeutic activities of TQ, this molecule is not yet in the clinical trials, restricted by its poor biopharmaceutical properties including photo-instability.Area covered: This review compiles the different types of polymeric and lipidic nanocarriers (NCs), encapsulating TQ for their improved oral bioavailability, and augmented in vitro and in vivo efficacy, evidenced on various pathologies. Furthermore, we provide a comprehensive overview of TQ in relation to its encapsulation approaches advancing the delivery and improving the efficacy of TQ.Expert opinion: TQ was first identified in the essential oil of Nigella sativa L. black seed. TQ has not been used in formulations because it is a highly hydrophobic drug having poor aqueous solubility. To deal with the poor physicochemical problems associated with TQ, various NCs encapsulating TQ have been tried in the past. Nevertheless, these NCs could be impending in bringing forth this potential molecule to clinical reality. This will also be beneficial for a large research community including pharmaceutical & biological sciences and translational researchers.

The E2F family as potential biomarkers and therapeutic targets in colon cancer

Background

The E2F family is a group of genes encoding a series of transcription factors in higher eukaryotes and participating in the regulation of cell cycle and DNA synthesis in mammals. This study was designed to investigate the role of E2F family in colon cancer.

Methods

In this study, the transcriptional levels of E2F1-8 in patients with colon cancer from GEPIA was examined. Meanwhile, the immunohistochemical data of the eight genes were also obtained in the The Human Protein Atlas website. Additionally, we re-identified the mRNA expression levels of these genes via real time PCR. Furthermore, the association between the levels of E2F family and stage plot as wells overall survival of patients with colon cancer were analyzed.

Results

We found that the mRNA and protein levels of E2F1, E2F2, E3F3, E2F5, E2F7 and E2F8 were significantly higher in colon cancer tissues than in normal colon tissues while the expression levels of E2F4 and E2F6 displayed no significant difference between colon cancer tissues and normal tissues. Additionally, E2F3, E2F4, E2F7 and E2F8 were significantly associated with the stages of colon cancer. The Kaplan-Meier Plotter showed that the high levels of E2F3 conferred a worse overall survival and disease free survival of patients with colon cancer. Also, high levels of E2F4 resulted in a worse overall survival.

Conclusion

Our study implied that E2F3, E2F4, E2F7 and E2F8 are potential targets of precision therapy for patients with colon cancer while E2F1, E2F2, E3F3, E2F5, E2F7 and E2F8 are potential biomarkers for the diagnosis of colon cancer.

The Effects of Thymoquinone on Viability, and Anti-apoptotic Factors (BCL-XL, BCL-2, MCL-1) in Prostate Cancer (PC3) Cells: An In Vitro and Computer-Simulated Environment Study

Purpose: Since active plant ingredients can induce apoptosis in many tumors, in this study we evaluate the apoptotic effects of thymoquinone (TQ) on PC3 cells. Also, we predicted the interaction of TQ with BCL-XL, BCL-2, and MCL-1anti-apoptotic factors by computer-simulated environment. Methods: PC3 cells were treated with different concentrations of TQ (0- 80 µM) and IC₅₀ was determined using 3-(4, 5-dimethylthiaztol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Apoptotic and cytotoxicity effects of TQ were analyzed using flowcytometry and comet assay, respectively. Changes in energy and the molecular interactions of TQ with BCL-XL, BCL-2 and MCL-1 anti-apoptotic factors were investigated using simulation. Results: IC₅₀ value was 40 µM. TQ led to the destruction of the genome of PC3 cells and inducing apoptosis. Molecular dynamics (MD) revealed that the root mean-square deviation (RMSD), root mean square fluctuation (RMSF), radius of gyration (Rg), and the number of hydrogen and hydrophobic bonds between TQ and residues of BCL-2, BCL-XL and MCL-1were significantly (P<0.001) changed. TQ makes a more stable and stronger connection with BCL-XL compared to BCL-2 and MCL-1 and inhibits BCL-XL non-competitively. Conclusion: Our results demonstrated that TQ not only led to apoptosis, at least partly, due to reduction in the Coil, Turn, and Bend structure of BCL-XL but also caused a decrease in the Rg and RMSD value of BCL-XL, MCL-1, and BCL-2.

Association of imputed prostate cancer transcriptome with disease risk reveals novel mechanisms

Here we train cis-regulatory models of prostate tissue gene expression and impute expression transcriptome-wide for 233,955 European ancestry men (14,616 prostate cancer (PrCa) cases, 219,339 controls) from two large cohorts. Among 12,014 genes evaluated in the UK Biobank, we identify 38 associated with PrCa, many replicating in the Kaiser Permanente RPGEH. We report the association of elevated TMPRSS2 expression with increased PrCa risk (independent of a previously-reported risk variant) and with increased tumoral expression of the TMPRSS2:ERG fusion-oncogene in The Cancer Genome Atlas, suggesting a novel germline-somatic interaction mechanism. Three novel genes, HOXA4, KLK1, and TIMM23, additionally replicate in the RPGEH cohort. Furthermore, 4 genes, MSMB, NCOA4, PCAT1, and PPP1R14A, are associated with PrCa in a trans-ethnic meta-analysis (N = 9117). Many genes exhibit evidence for allele-specific transcriptional activation by PrCa master-regulators (including androgen receptor) in Position Weight Matrix, Chip-Seq, and Hi-C experimental data, suggesting common regulatory mechanisms for the associated genes.

The Chemopreventive Activity of Indonesia Medicinal Plants Targeting on Hallmarks of Cancer

Cancer remains a complex disease with increasing global mortality and morbidity. Numerous theories have been established to understand the biological mechanism underlying cancer. One of the most renowned frameworks is the hallmark of cancer proposed by Hanahan and Weinberg that covers ten eminent characteristics of cancer: (i) genome instability and mutation, (ii) sustaining proliferative signaling, (iii) evading growth suppressor, (iv) enabling replicative immortality, (v) resisting cell death, (vi) inducing angiogenesis, (vii) activating invasion and metastasis, (viii) avoiding immune destruction, (ix) tumor-promoting inflammation, and (x) deregulating cellular energetics. These hallmarks provide a rational approach to design an anticancer therapy. In the current review, we summarized specific target molecules on each hallmark of cancer. Further, we evaluated the biological activity of several Indonesia medicinal plants against those specific targets. We explicated the anticancer and chemopreventive activities of some medicinal plants that have been used for centuries by local communities in Indonesia, including Curcuma genus, Brucea javanica, Boesenbergia pandurata, Caesalpinia sappan, and Nigella sativa. Interestingly, these medicinal plants target several hallmarks of cancer, and even Curcuma genus exhibited biological activities that target all hallmarks of cancer. Further, we also discuss several strategies to develop those medicinal plants and/or their active compounds as anticancer and chemopreventive agents.

Thymoquinone Enhances the Effect of Gamma Knife in B16-F10 Melanoma Through Inhibition of Phosphorylated STAT3

BACKGROUND

Patients with brain metastasis from melanoma have a dismal prognosis with poor survival time. Gamma Knife (GK) is an effective treatment to control brain metastasis from melanoma. Thymoquinone (TQ) has emerged as a potential therapeutic option due to its antiproliferative effects on various cancers. The purpose of the study was to assess the effect of GK on B16-F10 melanoma cells in vitro and intracerebral melanoma in vivo, and its synergistic effect in combination with TQ.

METHODS

The effects of GK and combination treatment of GK and TQ were studied on B16-F10 melanoma cells by evaluating cytotoxicity with an adenosine triphosphate assay, apoptosis by acridine orange staining, and genotoxicity by comet assay. Western blot analysis was performed to investigate the expression of STAT3, p-STAT3 (Tyr705), JAK2, p-JAK2, caspase-3, Bax, Bcl-2, survivin, and β-actin. Expression of inflammatory cytokines was assessed by enzyme-linked immunosorbent assay. GK alone and in combination with TQ was assessed in an established intracerebral melanoma tumor in mice.

RESULTS

The effects of GK on cytotoxicity, genotoxicity, and apoptosis were enhanced by TQ in B16-F10 melanoma cells. GK induced apoptosis through inhibition of p-STAT3 expression, which in turn regulated pro- and antiapoptotic proteins such as caspase-3, Bax, Bcl-2, and survivin. Adding TQ to GK irradiation further enhanced this apoptotic effect of GK irradiation. GK was shown to reduce the levels of tumor-related inflammatory cytokines in B16-F10 melanoma cells. This effect was more pronounced when TQ was added to GK irradiation. GK with 15 Gy increased the survival of mice with intracerebral melanoma compared with untreated mice. However, despite the additive effect of TQ in addition to GK irradiation on B16-F10 melanoma cells in vitro, TQ did not add any significant survival benefit to GK treatment in mice with intracerebral melanoma.

CONCLUSIONS

Our findings suggest that TQ would be a potential therapeutic agent in addition to GK to enhance the antitumor effect of irradiation. Further studies are required to support our findings.

Dissecting the roles of thymoquinone on the prevention and the treatment of hepatocellular carcinoma: an overview on the current state of knowledge

Thymoquinone (TQ) is the principal active monomer isolated from the seed of the medicinal plant Nigella sativa. This compound has antitumor effects against various types of cancer including hepatocellular carcinoma (HCC), mainly due to its anti-inflammatory and anti-oxidant properties. Several pre-clinical studies showed that TQ, through the modulation of different molecular pathways, is able to induce anti-apoptotic and anti-proliferative effects in HCC, without signs of toxicity. Moreover, it has been suggested that TQ has hepatoprotective effects by enhancing the tolerability and effectivity of neoadjuvant therapy prior to liver surgery, although the underlying mechanisms are not completely understood. Based on these findings, is assumable that TQ could represent a valuable therapeutic option for patients suffering from HCC. In this review, we summarize the potential roles of TQ in the prevention and treatment of HCC, by revising the preclinical studies and by highlighting the potential applications of TQ as a therapeutic choice for HCC treatment into clinical practices.

Thymoquinone Inhibits Bone Metastasis of Breast Cancer Cells Through Abrogation of the CXCR4 Signaling Axis

Overexpression of chemokine receptor type 4 (CXCR4) has been found to be associated with increased cell proliferation, metastasis and also act as an indicator of poor prognosis in patients with breast cancer. Therefore, new agents that can abrogate CXCR4 expression have potential against breast cancer metastasis. In this study, we examined the potential effect of thymoquinone (TQ), derived from the seeds of Nigella sativa, on the expression and regulation of CXCR4 in breast cancer cells. TQ was found to inhibit the expression of CXCR4 in MDA-MB-231 triple negative breast cancer (TNBC) cells in a dose- and time-dependent manner. It was noted that suppression of CXCR4 by TQ was possibly transcriptionally regulated, as treatment with this drug caused down-regulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation and suppression of NF-κB binding to the CXCR4 promoter. Pretreatment with a proteasome inhibitor and/or lysosomal stabilization did not affect TQ induced suppression of CXCR4. Down-regulation of CXCR4 was further correlated with the inhibition of CXCL12-mediated migration and invasion of MDA-MB-231 cells. Interestingly, it was observed that the deletion of p65 could reverse the observed anti-invasive/anti-migratory effects of TQ in breast cancer cells. TQ also dose-dependently inhibited MDA-MB-231 tumor growth and tumor vascularity in a chick chorioallantoic membrane assay model. We also observed TQ (2 and 4 mg/kg) treatment significantly suppressed multiple lung, brain, and bone metastases in a dose-dependent manner in a metastasis breast cancer mouse model. Interestingly, H&E and immunohistochemical analysis of bone isolated from TQ treated mice indicated a reduction in number of osteolytic lesions and the expression of metastatic biomarkers. In conclusion, the results indicate that TQ primarily exerts its anti-metastatic effects by down-regulation of NF-κB regulated CXCR4 expression and thus has potential for the treatment of breast 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.

Thymoquinone is protective against 2,3,7,8-tetrachlorodibenzo-p-dioxin induced hepatotoxicity

We investigated changes in rat liver tissues following administration of thymoquinone (TQ) against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced hepatotoxicity. Fifty rats were assigned randomly to five groups of 10 as follows: control, corn oil, TCDD, TQ and TCDD + TQ. Biochemical and histopathological analyses were conducted on liver tissue. We found that 30 day TCDD administration caused histopathological changes in liver including thickening of Glisson's capsule, intracytoplasmic vacuolization in hepatocytes, sinusoidal dilation, vascular and sinusoidal congestion and inflammatory cell infiltration. TCDD administration increased malondialdehyde (MDA), total oxidant status (TOS), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels in rat liver tissue and reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant status (TAS) levels compared to all other groups. In the TQ treated group, GSH, SOD, CAT and TAS levels increased compared to all other groups. MDA, TOS, ALT, AST, ALP levels decreased compared to all other groups. Our histological findings were consistent with the biochemical findings. The oxidative and histologic effects of TCDD were eliminated by TQ treatment. TCDD administration caused oxidative stress in rat liver and TQ administered with TCDD prevented TCDD induced hepatotoxicity. TQ could be considered an alternative anti-TCDD toxicity agent.

Par-4-dependent p53 up-regulation plays a critical role in thymoquinone-induced cellular senescence in human malignant glioma cells

Thymoquinone (TQ), the predominant bioactive constituent present in black cumin (Nigella sativa), exerts tumor suppressive activity against a wide variety of cancer cells. Cellular senescence, characterized by stable and long term loss of proliferative capacity, acts as a potent tumor suppressive mechanism. Here, we provide evidence for the first time that TQ suppresses growth of glioma cells by potentially inducing the expression of prostate apoptosis response-4 (Par-4) tumor suppressor protein. In turn, TQ-induced Par-4 expression triggers cellular senescence, as evidenced by increasing cellular size, β-galactosidase staining, G1 phase arrest, and increased expression of senescence markers such as p53, p21, Rb, and decreased expression of lamin B1, cyclin E and cyclin depended kinase-2 (CDK-2). Further, overexpression of Par-4 significantly increases the expression of p53 and its downstream target p21, and increases β-galactosidase positive cells, while siRNA/shRNA mediated-knockdown of Par-4 reverses the TQ-induced effects. Altogether, we describe a novel mechanism of cross talk between Par-4 and p53, that plays a critical role in TQ-induced senescence in human malignant glioma cells.

Medicinal Plants from Near East for Cancer Therapy

Background: Cancer is one of the major problems affecting public health worldwide. As other cultures, the populations of the Near East rely on medicinal herbs and their preparations to fight cancer. Methods: We compiled data derived from historical ethnopharmacological information as well as in vitro and in vivo results and clinical findings extracted from different literature databases including (PubMed, Scopus, Web of Science, and Google Scholar) during the past two decades. Results: In this survey, we analyzed the huge amount of data available on anticancer ethnopharmacological sources used in the Near East. Medicinal herbs are the most dominant ethnopharmacological formula used among cancer's patients in the Near East. The data obtained highlight for the first time the most commonly used medicinal plants in the Near East area for cancer treatment illustrating their importance as natural anticancer agents. The literature survey reveals that various Arum species, various Artemisia species, Calotropis procera, Citrullus colocynthis, Nigella sativa, Pulicaria crispa, various Urtica species, Withania somnifera, and others belong to the most frequently used plants among cancer patients in the Near East countries. Molecular modes of action that have been investigated for plant extracts and isolated compounds from Near East include cell cycle arrest and apoptosis induction with participation of major player in these processes such as p53 and p21, Bcl-2, Bax, cytochrome c release, poly (ADP-ribose) polymerase cleavage, activation of caspases, etc. Conclusion: The ethnopharmacology of the Near East was influenced by Arabic and Islamic medicine and might be promising for developing new natural and safe anticancer agents. Further research is required to elucidate their cellular and molecular mechanisms and to estimate their clinical activity.

Therapeutic Potential of Thymoquinone in Glioblastoma Treatment: Targeting Major Gliomagenesis Signaling Pathways

Glioblastoma multiforme (GBM) is one of the most devastating brain tumors with median survival of one year and presents unique challenges to therapy because of its aggressive behavior. Current treatment strategy involves surgery, radiotherapy, immunotherapy, and adjuvant chemotherapy even though optimal management requires a multidisciplinary approach and knowledge of potential complications from both the disease and its treatment. Thymoquinone (TQ), the main bioactive component of Nigella sativa L., has exhibited anticancer effects in numerous preclinical studies. Due to its multitargeting nature, TQ interferes in a wide range of tumorigenic processes and counteract carcinogenesis, malignant growth, invasion, migration, and angiogenesis. TQ can specifically sensitize tumor cells towards conventional cancer treatments and minimize therapy-associated toxic effects in normal cells. Its potential to enter brain via nasal pathway due to volatile nature of TQ adds another advantage in overcoming blood-brain barrier. In this review, we summarized the potential role of TQ in different signaling pathways in GBM that have undergone treatment with standard therapeutic modalities or with TQ. Altogether, we suggest further comprehensive evaluation of TQ in preclinical and clinical level to delineate its implied utility as novel therapeutics to combat the challenges for the treatment of GBM.

Anti-cancer properties and mechanisms of action of thymoquinone, the major active ingredient of Nigella sativa

Over the past two decades, studies have documented the wide-range anti-cancer effects of Nigella sativa, known as black seed or black cumin. Thymoquinone (TQ), its major active ingredient, has also been extensively studied and reported to possess potent anti-cancer properties. Herein, we provide a comprehensive review of the findings related to the anti-cancer activity of TQ. The review focuses on analyzing experimental studies performed using different in vitro and in vivo models to identify the anti-proliferative, pro-apoptotic, anti-oxidant, cytotoxic, anti-metastatic, and NK-dependent cytotoxic effects exerted by TQ. In addition, we pinpoint the molecular mechanisms underlying these effects and the signal transduction pathways implicated by TQ. Our analysis show that p53, NF-κB, PPARγ, STAT3, MAPK, and PI3K/AKT signaling pathways are among the most significant pathways through which TQ mediates its anti-cancer activity. Experimental findings and recent advances in the field highlight TQ as an effective therapeutic agent for the suppression of tumor development, growth and metastasis for a wide range of tumors.

Review on the Potential Therapeutic Roles of Nigella sativa in the Treatment of Patients with Cancer: Involvement of Apoptosis: - Black cumin and cancer

Nigella sativa (N. sativa, family Ranunculaceae) is a medicinal plant that has been widely used for centuries throughout the world as a natural remedy. A wide range of chemical compounds found in N. sativa expresses its vast therapeutic effects. Thymoquinone (TQ) is the main component (up to 50%) in the essential oil of N. sativa. Also, pinene (up to 15%), p-cymene (40%), thymohydroquinone (THQ), thymol (THY), and dithymoquinone (DTQ) are other pharmacologically active compounds of its oil. Other terpenoid compounds, such as carvacrol, carvone, 4-terpineol, limonenes, and citronellol, are also found in small quantities in its oil. The main pharmacological characteristics of this plant are immune system stimulatory, anti-inflammatory, hypotensive, hepatoprotective, antioxidant, anti-cancer, hypoglycemic, anti-tussive, milk production, uricosuric, choleretic, anti-fertility, and spasmolytic properties. In this regard, we have searched the scientific databases PubMed, Web of Science, and Google Scholar with keywords of N. sativa, anti-cancer, apoptotic effect, antitumor, antioxidant, and malignancy over the period from 2000 to 2017. The effectiveness of N. sativa against cancer in the blood system, kidneys, lungs, prostate, liver, and breast and on many malignant cell lines has been shown in many studies, but the molecular mechanisms behind that anti-cancer role are still not clearly understood. From among the many effects of N. sativa, including its anti-proliferative effect, cell cycle arrest, apoptosis induction, ROS generation, anti-metastasis/anti-angiogenesis effects, Akt pathway control, modulation of multiple molecular targets, including p53, p73, STAT-3, PTEN, and PPAR-γ, and activation of caspases, the main suggestive anti-cancer mechanisms of N. sativa are its free radical scavenger activity and the preservation of various anti-oxidant enzyme activities, such as glutathione peroxidase, catalase, and glutathione-S-transferase. In this review, we highlight the molecular mechanisms of apoptosis and the anti-cancer effects of N. sativa, with a focus on its molecular targets in apoptosis pathways.