Therapeutic potential of tocotrienols as chemosensitizers in cancer therapy.

Chemoresistance is the adaptation of cancer cells against therapeutic agents. When exhibited by cancer cells, chemoresistance helps them to avoid apoptosis, cause relapse, and metastasize, making it challenging for chemotherapeutic agents to treat cancer. Various strategies like dosage modification of drugs, nanoparticle-based delivery of chemotherapeutics, antibody-drug conjugates, and so on are being used to target and reverse chemoresistance, one among such is combination therapy. It uses the combination of two or more therapeutic agents to reverse multidrug resistance and improve the effects of chemotherapy. Phytochemicals are known to exhibit chemosensitizing properties and are found to be effective against various cancers. Tocotrienols (T3) and tocopherols (T) are natural bioactive analogs of vitamin E, which exhibit important medicinal value and potential curative properties apart from serving as an antioxidant and nutrient supplement. Notably, T3 exhibits a variety of pharmacological activities like anticancer, anti-inflammatory, antiproliferative, and so on. The chemosensitizing property of tocotrienol is exhibited by modulating several signaling pathways and molecular targets involved in cancer cell survival, proliferation, invasion, migration, and metastasis like NF-κB, STATs, Akt/mTOR, Bax/Bcl-2, Wnt/ß-catenin, and many more. T3 sensitizes cancer cells to chemotherapeutic drugs including cisplatin, doxorubicin, and paclitaxel increasing drug concentration and cytotoxicity. Discussed herewith are the chemosensitizing properties of tocotrienols on various cancer cell types when combined with various drugs and biological molecules.

Phytochemicals in cancer cell chemosensitization: Current knowledge and future perspectives.

Despite significant advancements made in the treatment of cancer during the past several decades, it remains one of the leading causes of death worldwide killing approximately 9.6 million people annually. The major challenge for therapeutic success is the development of chemoresistance in cancer cells against conventional chemotherapeutic agents via modulation of numerous survival and oncogenic signaling pathways. Therefore, sensitization of cancer cells to conventional drugs using multitargeted agents that suppress the survival and oncogenic pathways, in single or in combination, is an emerging strategy to overcome drug-resistance. During the last couple of decades, phytochemicals such as curcumin, resveratrol, tocotrienol and quercetin have emerged as potential chemosensitizing agents in cancer cells due to their less toxic and multitargeted properties. Numerous preclinical and clinical studies enumerated their potential to prevent drug resistance and sensitize cancer cells to chemotherapeutic agents by modulating several genes/proteins or pathways that regulate the key factors during the growth and progression of tumors such as inhibition of anti-apoptotic proteins, activation of pro-apoptotic proteins, reduced expression of different transcription factors, chemokines, enzymes, cell adhesion molecules, protein tyrosine kinases and cell cycle regulators. Therefore, natural chemosensitizing agents will have a special place in cancer treatment in the near future. This comprehensive review summarizes data obtained from various in vitro, in vivo and clinical studies to provide a new perspective for the application of agents obtained from "Mother Nature" as potential chemosensitizers for further cancer drug research and development.

Inflammation, NF-κB, and Chronic Diseases: How are They Linked?

Most chronic diseases, caused by lifestyle factors, appear to be linked to inflammation. Inflammation is activated mechanistically, and nuclear factor-κB (NF-κB) is a significant mediator. NF-κB, one of the most studied transcription factors, was first identified in the nucleus of B lymphocytes almost three decades ago. This protein has a key function in regulating the human immune system, and its dysregulation has been linked to many chronic diseases including asthma, cancer, diabetes, rheumatoid arthritis, inflammation, and neurological disorders. Physiologically, many cytokines have been discovered that activate NF-κB. Pathologically, environmental carcinogens such as cigarette smoke, radiation, bacteria, and viruses can also activate this transcription factor. NF-κB activation controls expression of more than 500 genes, and most are deleterious to the human body when dysregulated. More than 70,000 articles have been published regarding NF-κB. This review emphasizes the upside and downside of NF-κB in normal and disease conditions and the ways in which we can control this critical transcription factor in patients.

Upside and Downside of Tumor Necrosis Factor Blockers for Treatment of Immune/Inflammatory Diseases.

Tumor necrosis factor (TNF)-α, the most potent proinflammatory cytokine discovered to date, was first isolated in 1984 from human macrophage cells. Initially, it was thought to be a protein that was cytotoxic to tumor cells. But later, it was regarded as an agent that promotes inflammation and other chronic diseases found in humans. Currently, we know that the TNF superfamily (TNFS) has 19 members that perform a wide variety of functions via > 40 TNF receptors. Of TNFS members, TNF-α has been studied extensively and was found to be implicated in numerous autoimmune diseases, such as rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease, psoriasis, systemic lupus erythematosus, juvenile idiopathic arthritis, and diabetes. Thus, agents that can inhibit TNF-α have great potential for prevention and treatment of chronic diseases. To date, the U.S. Food and Drug Administration has approved many TNF-α blockers, such as etanercept, infliximab, adalimumab, certolizumab pegol, and golimumab. These agents can block TNF-α actions and be used to treat different diseases. However, the uses of TNF-α blockers are not without serious adverse effects. Therefore, natural TNF-α blockers are best for developing safe, efficacious, and affordable agents for prevention and treatment of chronic diseases. The current review details the TNFS, functions of TNF-α in normal and disease conditions, roles of TNF-α blockers, and advantages and disadvantages.

Therapeutic Emergence of Rhein as a Potential Anticancer Drug: A Review of Its Molecular Targets and Anticancer Properties.

According to the World Health Organization (WHO), cancer is the second-highest cause of mortality in the world, and it kills nearly 9.6 million people annually. Besides the fatality of the disease, poor prognosis, cost of conventional therapies, and associated side-effects add more burden to patients, post-diagnosis. Therefore, the search for alternatives for the treatment of cancer that are safe, multi-targeted, effective, and cost-effective has compelled us to go back to ancient systems of medicine. Natural herbs and plant formulations are laden with a variety of phytochemicals. One such compound is rhein, which is an anthraquinone derived from the roots of Rheum spp. and Polygonum multiflorum. In ethnomedicine, these plants are used for the treatment of inflammation, osteoarthritis, diabetes, and bacterial and helminthic infections. Increasing evidence suggests that this compound can suppress breast cancer, cervical cancer, colon cancer, lung cancer, ovarian cancer, etc. in both in vitro and in vivo settings. Recent studies have reported that this compound modulates different signaling cascades in cancer cells and can prevent angiogenesis and progression of different types of cancers. The present review highlights the cancer-preventing and therapeutic properties of rhein based on the available literature, which will help to extend further research to establish the chemoprotective and therapeutic roles of rhein compared to other conventional drugs. Future pharmacokinetic and toxicological studies could support this compound as an effective anticancer agent.

Honokiol for cancer therapeutics: A traditional medicine that can modulate multiple oncogenic targets.

In spite of billions of dollars expended on cancer research every year, the incidence rate and the mortality rate due to this widespread disease has increased drastically over the last few decades. Recent reports from the World Health Organization advocate that overall global cancer burden and deaths due to cancer are expected to double by the next decade. Synthetic drugs developed as chemotherapeutics have repeatedly shown adverse side effects and development of chemoresistance. Cancer is basically a multifactorial disease that necessitates the modulation of multiple targets and oncogenic signaling pathways. Honokiol (C18H18O2) is a biphenolic natural compound isolated from the leaves and barks of Magnolia plant species and has been extensively studied for its beneficial effects against several chronic diseases. Honokiol is capable of efficiently preventing the growth of wide variety of tumors such as those of brain, breast, cervical, colon, liver, lung, prostate, skin, and hematological malignancies. Recent work has shown that this phytochemical can modulate various molecular targets such as activation of pro-apoptotic factors, suppression of anti-apoptotic proteins and different transcription factors, downregulation of various enzymes, chemokines, cell surface adhesion molecules, and cell cycle proteins, and inhibition of activity of protein tyrosine kinases and serine/threonine kinases. Because of its pharmacological safety, honokiol can either be used alone or in combination with other chemotherapeutic drugs for the prevention and treatment of cancer. The current review describes in detail the various reports supporting these anti-cancer studies documented with this promising agent.

Chronic diseases, inflammation, and spices: how are they linked?

Extensive research within the last several decades has revealed that the major risk factors for most chronic diseases are infections, obesity, alcohol, tobacco, radiation, environmental pollutants, and diet. It is now well established that these factors induce chronic diseases through induction of inflammation. However, inflammation could be either acute or chronic. Acute inflammation persists for a short duration and is the host defense against infections and allergens, whereas the chronic inflammation persists for a long time and leads to many chronic diseases including cancer, cardiovascular diseases, neurodegenerative diseases, respiratory diseases, etc. Numerous lines of evidence suggest that the aforementioned risk factors induced cancer through chronic inflammation. First, transcription factors NF-κB and STAT3 that regulate expression of inflammatory gene products, have been found to be constitutively active in most cancers; second, chronic inflammation such as pancreatitis, prostatitis, hepatitis etc. leads to cancers; third, activation of NF-κB and STAT3 leads to cancer cell proliferation, survival, invasion, angiogenesis and metastasis; fourth, activation of NF-κB and STAT3 leads to resistance to chemotherapy and radiation, and hypoxia and acidic conditions activate these transcription factors. Therefore, targeting these pathways may provide opportunities for both prevention and treatment of cancer and other chronic diseases. We will discuss in this review the potential of various dietary agents such as spices and its components in the suppression of inflammatory pathways and their roles in the prevention and therapy of cancer and other chronic diseases. In fact, epidemiological studies do indicate that cancer incidence in countries such as India where spices are consumed daily is much lower (94/100,000) than those where spices are not consumed such as United States (318/100,000), suggesting the potential role of spices in cancer prevention.

Tocotrienols: The promising analogues of vitamin E for cancer therapeutics.

Despite the significant advancements in the diagnosis and treatment of cancer, it still remains one of the most fatal diseases in the world due to the lack of sensitive diagnosis methods and effective drugs. Therefore, discovering novel therapies that are safe, efficacious and affordable are required for the better management of this disease. Tocotrienols, analogues of vitamin E have gained increased attention due to their safety and efficacy. Extensive research over the past several years has strongly indicated that tocotrienols can efficiently prevent/inhibit the growth of different cancers such as cancers of blood, brain, breast, cervical, colon, liver, lung, pancreas, prostate, skin, stomach etc. This is mainly accredited to their ability to modulate various molecular targets involved in cancer cell proliferation, survival, invasion, angiogenesis, and metastasis such as NF-κB, STAT3, Akt/mTOR, etc. In addition, increasing lines of evidence has shown that tocotrienols can sensitize cancer cells to chemotherapeutic agents such as celecoxib, doxorubicin, erlotinib, gefitinib, gemcitabine, paclitaxel, statin etc. Moreover, several clinical trials have confirmed the safety and tolerability of tocotrienols in humans. This review summarizes the potential of tocotrienols for the prevention and treatment of different cancers based on the available in vitro, in vivo and clinical studies.

Unlocking the potential of Berberine: Advancing cancer therapy through chemosensitization and combination treatments.

Despite considerable progress in cancer treatment options, resistance to chemotherapeutic drugs remains a significant challenge. This review focuses on Berberine (BBR), an isoquinoline alkaloid found in various medicinal plants, which has garnered attention in the field of oncology for its anticancer potential either alone or in combination with other compounds and its ability to modulate chemoresistance, acting as a natural chemosensitizer. BBR's ability to modulate chemoresistance is attributed to its diverse mechanisms of action, including inducing DNA breaks, inhibition of drug efflux pumps, modulation of apoptosis and necroptosis, downregulating multidrug resistance genes, enhancing immune response, suppressing angiogenesis and targeting multiple pathways within cancer cells, including protein kinase B/mammalian target of rapamycin (Akt/mTOR), epidermal growth factor receptor (EGFR), mitogen-activated protein kinase (MAPK), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), poly(ADP-ribose) polymerase (PARP1), janus kinase/signal transducers and activators of transcription (JAK-STAT), Wnt/ß-catenin etc. Moreover, BBR, in combination with other compounds, also offers a promising approach to cancer therapy, enforcing its broad-spectrum anticancer effects. Therefore, this review aims to elucidate the intricate mechanism of action of BBR in combinatorial therapy as a potential chemosensitizer to increase the efficiency of several drugs, including cisplatin, doxorubicin, lapatinib, tamoxifen, irinotecan, niraparib, etc. in various cancers. Additionally, this review briefly covers the origin and biological activities of BBR, exploring the specific actions underlying its anticancer effects. Further, pharmacokinetic properties of BBR are also discussed, providing insight into its therapeutic potential and optimization of its use in cancer treatment.

Harnessing Sulforaphane Potential as a Chemosensitizing Agent: A Comprehensive Review.

Recent advances in oncological research have highlighted the potential of naturally derived compounds in cancer prevention and treatment. Notably, sulforaphane (SFN), an isothiocyanate derived from cruciferous vegetables including broccoli and cabbage, has exhibited potent chemosensitizing capabilities across diverse cancer types of bone, brain, breast, lung, skin, etc. Chemosensitization refers to the enhancement of cancer cell sensitivity to chemotherapy agents, counteracting the chemoresistance often developed by tumor cells. Mechanistically, SFN orchestrates this sensitization by modulating an array of cellular signaling pathways (e.g., Akt/mTOR, NF-κB, Wnt/ß-catenin), and regulating the expression and activity of pivotal genes, proteins, and enzymes (e.g., p53, p21, survivin, Bcl-2, caspases). When combined with conventional chemotherapeutic agents, SFN synergistically inhibits cancer cell proliferation, invasion, migration, and metastasis while potentiating drug-induced apoptosis. This positions SFN as a potential adjunct in cancer therapy to augment the efficacy of standard treatments. Ongoing preclinical and clinical investigations aim to further delineate the therapeutic potential of SFN in oncology. This review illuminates the multifaceted role of this phytochemical, emphasizing its potential to enhance the therapeutic efficacy of anti-cancer agents, suggesting its prospective contributions to cancer chemosensitization and management.

The Promise of Epigenetics Research in the Treatment of Appendiceal Neoplasms.

Appendiceal cancers (AC) are a rare and heterogeneous group of malignancies. Historically, appendiceal neoplasms have been grouped with colorectal cancers (CRC), and treatment strategies have been modeled after CRC management guidelines due to their structural similarities and anatomical proximity. However, the two have marked differences in biological behavior and treatment response, and evidence suggests significant discrepancies in their respective genetic profiles. In addition, while the WHO classification for appendiceal cancers is currently based on traditional histopathological criteria, studies have demonstrated that histomorphology does not correlate with survival or treatment response in AC. Due to their rarity, appendiceal cancers have not been studied as extensively as other gastrointestinal cancers. However, their incidence has been increasing steadily over the past decade, making it crucial to identify new and more effective strategies for detection and treatment. Recent efforts to map and understand the molecular landscape of appendiceal cancers have unearthed a wealth of information that has made it evident that appendiceal cancers possess a unique molecular profile, distinct from other gastrointestinal cancers. This review focuses on the epigenetic landscape of epithelial appendiceal cancers and aims to provide a comprehensive overview of the current state of knowledge of epigenetic changes across different appendiceal cancer subtypes, highlighting the challenges as well as the promise of employing epigenetics in the quest for the detection of biomarkers, therapeutic targets, surveillance markers, and predictors of treatment response and survival in epithelial appendiceal neoplasms.

Utility of promoter hypermethylation in malignant risk stratification of intraductal papillary mucinous neoplasms.

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMNs), a type of cystic pancreatic cancer (PC) precursors, are increasingly identified on cross-sectional imaging and present a significant diagnostic challenge. While surgical resection of IPMN-related advanced neoplasia, i.e., IPMN-related high-grade dysplasia or PC, is an essential early PC detection strategy, resection is not recommended for IPMN-low-grade dysplasia (LGD) due to minimal risk of carcinogenesis, and significant procedural risks. Based on their promising results in prior validation studies targeting early detection of classical PC, DNA hypermethylation-based markers may serve as a biomarker for malignant risk stratification of IPMNs. This study investigates our DNA methylation-based PC biomarker panel (ADAMTS1, BNC1, and CACNA1G genes) in differentiating IPMN-advanced neoplasia from IPMN-LGDs. METHODS: Our previously described genome-wide pharmaco-epigenetic method identified multiple genes as potential targets for PC detection. The combination was further optimized and validated for early detection of classical PC in previous case-control studies. These promising genes were evaluated among micro-dissected IPMN tissue (IPMN-LGD: 35, IPMN-advanced neoplasia: 35) through Methylation-Specific PCR. The discriminant capacity of individual and combination of genes were delineated through Receiver Operating Characteristics curve analysis. RESULTS: As compared to IPMN-LGDs, IPMN-advanced neoplasia had higher hypermethylation frequency of candidate genes: ADAMTS1 (60% vs. 14%), BNC1 (66% vs. 3%), and CACGNA1G (25% vs. 0%). We observed Area Under Curve (AUC) values of 0.73 for ADAMTS1, 0.81 for BNC1, and 0.63 for CACNA1G genes. The combination of the BNC1/ CACNA1G genes resulted in an AUC of 0.84, sensitivity of 71%, and specificity of 97%. Combining the methylation status of the BNC1/CACNA1G genes, blood-based CA19-9, and IPMN lesion size enhanced the AUC to 0.92. CONCLUSION: DNA-methylation based biomarkers have shown a high diagnostic specificity and moderate sensitivity for differentiating IPMN-advanced neoplasia from LGDs. Addition of specific methylation targets can improve the accuracy of the methylation biomarker panel and enable the development of noninvasive IPMN stratification biomarkers.

Loss of TIPE3 reduced the proliferation, survival and migration of lung cancer cells through inactivation of Akt/mTOR, NF-κB, and STAT-3 signaling cascades.

Lung cancer is the foremost cause of cancer related mortality among men and one of the most fatal cancers among women. Notably, the 5-year survival rate of lung cancer is very low; 5% in developing countries. This low survival rate can be attributed to factors like late stage diagnosis, rapid postoperative recurrences in the patients undergoing treatment and development of chemoresistance against different agents used for treating lung cancer. Therefore, in this study we evaluated the potential of a recently identified protein namely TIPE3 which is known as a transfer protein of lipid second messengers as a lung cancer biomarker. TIPE3 was found to be significantly upregulated in lung cancer tissues indicating its role in the positive regulation of lung cancer. Supporting this finding, knockout of TIPE3 was also found to reduce the proliferation, survival and migration of lung cancer cells and arrested the G2 phase of cell cycle through inactivation of Akt/mTOR, NF-κB, STAT-3 signaling. It is well evinced that tobacco is the major risk factor of lung cancer which affects both males and females. Therefore, this study also evaluated the involvement of TIPE3 in tobacco mediated lung carcinogenesis. Notably, this study shows for the first time that TIPE3 positively regulates tobacco induced proliferation, survival and migration of lung cancer through modulation of Akt/mTOR signaling. Thus, TIPE3 plays critical role in the pathogenesis of lung cancer and hence it can be specifically targeted to develop novel therapeutic strategies.

Inflection of Akt/mTOR/STAT-3 cascade in TNF-α induced protein 8 mediated human lung carcinogenesis.

Lung cancer is the leading cause of cancer-related death across the globe. Despite the marked advances in detection and therapeutic approaches, management of lung cancer patients remains a major challenge to oncologists which can be mainly attributed to late stage diagnosis, tumor recurrence and chemoresistance. Therefore, to overthrow these limitations, there arises a vital need to develop effective biomarkers for the successful management of this aggressive cancer type. Notably, TNF-alpha induced protein 8 (TIPE), a nuclear factor-kappa B (NF-κB)-inducible, oncogenic molecule and cytoplasmic protein which is involved in the regulation of T lymphocyte-mediated immunity and different processes in tumor cells such as proliferation, cell death and evasion of growth suppressors, might serve as one such biomarker which would facilitate effective management of lung cancer. Expression studies revealed this protein to be significantly upregulated in different lung cancer types, pathological conditions, stages and grades of lung tumor compared to normal human lung tissues. In addition, knockout of TIPE led to the reduced proliferation, survival, invasion and migration of lung cancer cells. Furthermore, TIPE was found to function through modulation of Akt/mTOR/STAT-3 signaling cascade. This is the first report which shows the involvement of TIPE in tobacco induced lung carcinogenesis. It positively regulated nicotine, NNK, NNN, and BaP induced proliferation, survival and migration of lung cancer cells possibly via Akt/STAT-3 signaling. Thus, this protein possesses important role in the pathogenesis of lung tumor and hence it can be targeted for developing newer therapeutic interventions for the clinico-management of lung cancer.

Is curcumin bioavailability a problem in humans: lessons from clinical trials.

Introduction: Since ancient times, turmeric has been used in several folklore remedies against various ailments. The principal component of turmeric is curcumin and its efficacy has been advocated in various in vitro, in vivo and clinical studies for different chronic diseases. However, some studies suggest that curcumin bioavailability is a major problem. Areas covered: This article discusses over 200 clinical studies with curcumin that have demonstrated the pronounced protective role of this compound against cardiovascular diseases, inflammatory diseases, metabolic diseases, neurological diseases, skin diseases, liver diseases, various types of cancer, etc. The review also describes the combination of curcumin with many natural and synthetic compounds as well as various formulations of curcumin that have shown efficacy in multiple clinical studies. Expert opinion: The therapeutic potential of curcumin, as demonstrated by clinical trials has overpowered the myth that poor bioavailability of curcumin poses a problem. Low curcumin bioavailability in certain studies has been addressed by using higher concentrations of curcumin within nontoxic limits. Moreover, curcumin, in combination with other compounds or as formulations, has shown enhanced bioavailability. Hence, bioavailability is not a problem in the curcumin-mediated treatment of chronic diseases. Therefore, this golden nutraceutical presents a safe, low-cost and effective treatment modality for different chronic diseases.

Cancer drug development: The missing links.

IMPACT STATEMENT: The success rate for cancer drugs which enter into phase 1 clinical trials is utterly less. Why the vast majority of drugs fail is not understood but suggests that pre-clinical studies are not adequate for human diseases. In 1975, as per the Tufts Center for the Study of Drug Development, pharmaceutical industries expended 100 million dollars for research and development of the average FDA approved drug. By 2005, this figure had more than quadrupled, to $1.3 billion. In order to recover their high and risky investment cost, pharmaceutical companies charge more for their products. However, there exists no correlation between drug development cost and actual sale of the drug. This high drug development cost could be due to the reason that all patients might not respond to the drug. Hence, a given drug has to be tested in large number of patients to show drug benefits and obtain significant results.

FBXW7 in Cancer: What Has Been Unraveled Thus Far?

: The FBXW7 (F-box with 7 tandem WD40) protein encoded by the gene FBXW7 is one of the crucial components of ubiquitin ligase called Skp1-Cullin1-F-box (SCF) complex that aids in the degradation of many oncoproteins via the ubiquitin-proteasome system (UPS) thus regulating cellular growth. FBXW7 is considered as a potent tumor suppressor as most of its target substrates can function as potential growth promoters, including c-Myc, Notch, cyclin E, c-JUN, and KLF5. Its regulators include p53, C/EBP-δ, Numb, microRNAs, Pin 1, Hes-5, BMI1, Ebp2. Mounting evidence has indicated the involvement of aberrant expression of FBXW7 for tumorigenesis. Moreover, numerous studies have also shown its role in cancer cell chemosensitization, thereby demonstrating the importance of FBXW7 in the development of curative cancer therapy. This comprehensive review emphasizes on the targets, functions, regulators and expression of FBXW7 in different cancers and its involvement in sensitizing cancer cells to chemotherapeutic drugs.

Nature-inspired development of unnatural meroterpenoids as the non-toxic anti-colon cancer agents.

Structural analogues of anti-cancer natural product, dysideanone, were synthesized starting from Wieland-Miescher ketone derivative. In vitro studies have been conducted to evaluate the anti-cancer potential of these unnatural meroterpenoids against colon cancer. Synthesized carbotetracycles were found to be more active as compared to their acyclic carbinol-derivatives. Unnatural carbotetracycles 4b-e, 4h, 4i and 12 were found to be highly effective against the human colon adenocarcinoma cells with IC50 concentrations of 7.5-20 µM. In this series, the carbotetracyclic catechol 4e (IC50 = 7.5 µM) and quinone 12 (IC50 = 8 µM) were found to be the most potent compounds having the IC50 of less than 10 µM with no cytotoxic effect on the normal cells. Downregulation of Cox-2 and survivin and cell cycle arrest eventually leading to apoptosis were found to be the underlying mechanism of the anti-cancer effect of these unnatural meroterpenoids.

Googling the Guggul (Commiphora and Boswellia) for Prevention of Chronic Diseases.

Extensive research during last 2 decades has revealed that most drugs discovered today, although costs billions of dollars for discovery, and yet they are highly ineffective in their clinical response. For instance, the European Medicines Agency has approved 68 anti-cancer drugs, and out of which 39 has reached the market level with no indication of increased survival nor betterment of quality of life. Even when drugs did improve survival rate compared to available treatment strategies, most of these were found to be clinically insignificant. This is a fundamental problem with modern drug discovery which is based on thinking that most chronic diseases are caused by alteration of a single gene and thus most therapies are single gene-targeted therapies. However, extensive research has revealed that most chronic diseases are caused by multiple gene products. Although most drugs designed by man are mono-targeted therapies, however, those designed by "mother nature" and have been used for thousands of years, are "multi-targeted" therapies. In this review, we examine two agents that have been around for thousands of years, namely "guggul" from Commiphora and Boswellia. Although we are all familiar with the search engine "google," this is another type of "guggul" that has been used for centuries and being explored for its various biological activities. The current review summarizes the traditional uses, chemistry, in vitro and in vivo biological activities, molecular targets, and clinical trials performed with these agents.

Therapeutic potential of gambogic acid, a caged xanthone, to target cancer.

Natural compounds have enormous biological and clinical activity against dreadful diseases such as cancer, as well as cardiovascular and neurodegenerative disorders. In spite of the widespread research carried out in the field of cancer therapeutics, cancer is one of the most prevalent diseases with no perfect treatment till date. Adverse side effects and the development of chemoresistance are the imperative limiting factors associated with conventional chemotherapeutics. For this reason, there is an urgent need to find compounds that are highly safe and efficacious for the prevention and treatment of cancer. Gambogic acid (GA) is a xanthone structure extracted from the dry, brownish gamboge resin secreted from the Garcinia hanburyi tree in Southeast Asia and has inherent anti-cancer properties. In this review, the molecular mechanisms underlying the targets of GA that are liable for its effective anti-cancer activity are discussed that reveal the potential of GA as a pertinent candidate that can be appropriately developed and designed into a capable anti-cancer drug.