Silymarin and Cancer: A Dual Strategy in Both in Chemoprevention and Chemosensitivity

Therapeutic Potential of Silymarin in Mitigating Paclitaxel-Induced Hepatotoxicity and Nephrotoxicity: Insights into Oxidative Stress, Inflammation, and Apoptosis in Rats

Background

Paclitaxel (PAX) is a widely used chemotherapy drug for various cancer types but often induces significant toxicity in multiple organ systems. Silymarin (SIL), a natural flavonoid, has shown therapeutic potential due to its multiple benefits.

Aims

To evaluate the therapeutic efficacy of SIL in mitigating liver and kidney damage induced by PAX in rats, focusing on oxidative stress, inflammation, and apoptosis pathways.

Study Design

Experimental animal model.

Methods

The study included 28 male Wistar rats aged 12-14 weeks weighing 270-300 g. The rats were divided into four groups: control, SIL, PAX, and PAX + SIL, with seven in each group. The rats received intraperitoneal (i.p.) injections at a dose of 2 mg per kilogram of body weight of PAX for 5 successive days, followed by oral gavage with 200 mg/kg body mass of SIL for 10 uninterrupted days. We examined the effect of SIL on specific serum biochemical parameters using an autoanalyzer and rat-specific kits. The spectrophotometric methods was used to investigate oxidative stress indicators in kidney and liver tissues. Aquaporin-2 (AQP-2), B-cell lymphoma-2 (Bcl-2), cysteine aspartate-specific protease-3 (caspase-3), interleukin-6 (IL-6), nuclear factor kappa B (NF-κB), and streptavidin-biotin staining were used to assess immunoreactivity in PAX-induced liver and kidney injury models.

Results

SIL treatment significantly reduced serum levels of alanine aminotransferase, aspartate aminotransferase, creatinine, urea, and C-reactive protein, indicating its effectiveness in treating PAX-induced liver and kidney injury. SIL treatment significantly reduced oxidative stress by increasing essential antioxidant parameters, such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione. It also reduced malondialdehyde levels in liver and kidney tissues of SIL-PAX groups (p < 0.05). SIL administration reduced NF-κB, caspase-3, and IL-6 expression while increasing Bcl-2 and AQP2 levels in liver and kidney tissues of rats treated with SIL and PAX (p < 0.05).

Conclusion

Our findings indicate the potential of SIL to alleviate PAX-induced liver and kidney damage in rats by reducing oxidative stress, inflammation, and apoptotic processes.

Bioactive compounds from nature: Antioxidants targeting cellular transformation in response to epigenetic perturbations induced by oxidative stress

Oxidative stress results from a persistent imbalance in oxidation levels that promotes oxidants, playing a crucial role in the early and sustained phases of DNA damage and genomic and epigenetic instability, both of which are intricately linked to the development of tumors. The molecular pathways contributing to carcinogenesis in this context, particularly those related to double-strand and single-strand breaks in DNA, serve as indicators of DNA damage due to oxidation in cancer cases, as well as factors contributing to epigenetic instability through ectopic expressions. Oxidative stress has been considered a therapeutic target for many years, and an increasing number of studies have highlighted the promising effectiveness of natural products in cancer treatment. In this regard, we present significant research on the therapeutic targeting of oxidative stress using natural molecules and underscore the essential role of oxidative stress in cancer. The consequences of stress, especially epigenetic instability, also offer significant therapeutic prospects. In this context, the use of natural epi-drugs capable of modulating and reorganizing the epigenetic network is beginning to emerge remarkably. In this review, we emphasize the close connections between oxidative stress, epigenetic instability, and tumor transformation, while highlighting the role of natural substances as antioxidants and epi-drugs in the anti-tumoral context.

Natural products for combating multidrug resistance in cancer

Cancer cells frequently develop resistance to chemotherapeutic therapies and targeted drugs, which has been a significant challenge in cancer management. With the growing advances in technologies in isolation and identification of natural products, the potential of natural products in combating cancer multidrug resistance has received substantial attention. Importantly, natural products can impact multiple targets, which can be valuable in overcoming drug resistance from different perspectives. In the current review, we will describe the well-established mechanisms underlying multidrug resistance, and introduce natural products that could target these multidrug resistant mechanisms. Specifically, we will discuss natural compounds such as curcumin, resveratrol, baicalein, chrysin and more, and their potential roles in combating multidrug resistance. This review article aims to provide a systematic summary of recent advances of natural products in combating cancer drug resistance, and will provide rationales for novel drug discovery.

Silibinin, Synergistically Enhances Vinblastine-Mediated Apoptosis in Triple Negative Breast Cancer Cell Line: Involvement of Bcl2/Bax and Caspase-3 Pathway

Background: Triple-negative breast cancer (TNBC) with a poor prognosis and survival is the most invasive subtype of breast cancer. Usually, TNBC requires a chemotherapy regimen at all stages, but chemotherapy drugs have shown many side effects. We assumed that combination therapy of vinblastine and silibinin might reduce the vinblastine toxicity and dose of vinblastine. Materials and Methods: The MDA-MB-231 were cells subjected to MTT assay for IC50 determination and combination effects, which were measured based on Chou-Talalay's method. The type of cell death was determined by using a Flow-cytometric assay. Cell death pathway markers, including Bcl-2, Bax, and caspase-3 were analyzed by western blot and Real-Time PCR. Results: The treatment of MDA-MB-231 cells exhibited IC50 and synergism at the combination of 30 µM of silibinin and 4 µm of vinblastine in cell viability assay (CI=0.69). YO-PRO-1/PI double staining results showed a significant induction of apoptosis when MDA-MB-231 cells were treated with a silibinin and vinblastine combination (p<0.01). Protein levels of Bax and cleaved caspase-3 were significantly upregulated, and Bcl-2 downregulated significantly. Significant upregulation of Bax (2.96-fold) and caspase-3 (3.46-fold) while Bcl-2 was downregulated by 2-fold. Conclusion: Findings established a preclinical rationale for the combination of silibinin and vinblastine. This combination produces synergistic effects in MDA-MB-231 cells by altering pro- and anti-apoptotic genes, which may reduce the toxicity and side effects of vinblastine.

Tellimagrandin-I and camptothin a exhibit chemopreventive effects in Salmonella enterica serovar Typhimurium strains and human lymphocytes

Tellimagrandin-I (TL) and camptothin A (CA) are ellagitannins widely found in diverse plant species. Numerous studies demonstrated their significant biological activities, which include antitumor, antioxidant, and hepatoprotective properties. Despite this protective profile, the effects of TL and CA on DNA have not been comprehensively investigated. Thus, the aim of this study was to determine the mutagenic and antimutagenic effects attributed to TL and CA exposure on Salmonella enterica serovar Typhimurium strains using the Ames test. In addition, the cytotoxic and genotoxic effects were examined on human lymphocytes, employing both trypan blue exclusion and CometChip assay. The antigenotoxic effect was determined following TL and CA exposure in the presence of co-treatment with doxorubicin (DXR). Our results from the Ames test indicated that TL or CA did not display marked mutagenic activity. However, TL or CA demonstrated an ability to protect DNA against the damaging effects of the mutagens 4-nitroquinoline-1-oxide and sodium azide, thereby exhibiting antimutagenic properties. In relation to human lymphocytes, TL or CA did not induce significant cytotoxic or genotoxic actions on these cells. Further, these ellagitannins exhibited an ability to protect DNA from damage induced by DOX during co-treatment, indicating their potential beneficial usefulness as antigenotoxic agents. In conclusion, the protective effects of TL or CA against mutagens, coupled with their absence of genotoxic and cytotoxic effects on human lymphocytes, emphasize their potential therapeutic value in chemopreventive strategies.

Co-treatment of silymarin and cisplatin inhibited cell proliferation, induced apoptosis in ovarian cancer

BACKGROUND

Ovarian cancer is one of the most lethal gynecological cancers among women worldwide. Cisplatin (Cis) is an effective chemotherapeutic agent used to treat several types of cancer. Silymarin (SLM) is an extract of medicinal plant Silybum marianum (milk thistle) with anti-inflammatory, anti-angiogenesis, antioxidant, and anticancer properties used alone or in combination with other drugs.

OBJECTIVE

This study aimed to explore the effects of co-treatment with SLM and Cis on A2780 human ovarian cancer cell lines.

METHODS

In this study, A2780 cells were treated with various concentrations of SLM and Cis, separately and in combination. Cell cytotoxicity, scratch, clonogenic, and flow-cytometry assays were accomplished to estimate cell viability, migration, colony formation, and apoptosis, respectively. Real-time PCR was utilized to determine the expression levels of miR-155 and miR-27a.

RESULTS

SLM significantly reduced the proliferation of A2780 cells in a concentration- and time-dependent manner. Combination treatment with SLM and Cis was more potent than either single treatment in reducing viability, suppressing migration, inhibiting colony formation, and promoting the induction of apoptosis. Additionally, gene expression analysis revealed a significant decline in the expression levels of miR-155 and miR-27a in response to all separate and combined treatments, and co-treatment was more effective than individual treatments in altering miRNAs expression.

CONCLUSION

Based on our findings, SLM boosts the anticancer activity of Cis and mitigates its side effects. Thus, the co-treatment of SLM and Cis can be proposed as a promising therapeutic strategy for further investigation.

Anti-tumor activity of silymarin nanoliposomes in combination with iron: In vitro and in vivo study

Combination therapy represents a promising strategy in cancer management by reducing chemotherapy resistance and associated side effects. Silymarin (SLM) has been extensively investigated due to its potent antioxidant properties and demonstrated efficacy against cancer cells. Under certain conditions however, polyphenolic compounds may also exhibit prooxidant activity by elevating intracellular reactive oxygen species (ROS), which can harm the target cells. In this study, we hypothesized that the simultaneous administration of iron (Fe) could alter the antioxidant characteristic of SLM nanoliposomes (SLM Lip) to a prooxidant state. Hence, we first developed a SLM Lip preparation using lipid film method, and then investigated the anti-oxidant properties as well as the cytotoxicity of the liposomal preparation. We also explored the efficacy of concomitant administration of iron sucrose and SML Lip on the tumor growth and survival of mice bearing tumors. We observed that exposing cells to iron, and consecutive treatment with SLM Lip (Fe + SLM Lip) could induce greater toxicity to 4 T1 breast cancer cells compared to SLM Lip. Further, Fe + SLM Lip combination demonstrated a time-dependent effect on reducing the catalase activity compared to SLM Lip, while iron treatment did not alter cell toxicity and catalase activity. In a mouse breast cancer model, the therapeutic efficacy of Fe + SLM Lip was superior compared to SLM Lip, and the treated animals survived longer. The histopathological findings did not reveal a significant damage to the major organs, whereas the most significant tumor necrosis was evident with Fe + SLM Lip treatment. The outcomes of the present investigation unequivocally underscored the prospective use of Fe + SLM combination in the context of cancer therapy, which warrants further scrutiny.

Co-Delivery of Silymarin and Metformin Dual-Loaded in Mesoporous Silica Nanoparticles Synergistically Sensitizes Breast Cancer Cell Line to Mitoxantrone Chemotherapy

The development nano-carriers based therapeutic methods is a potent strategy for enhancing cellular delivery of drugs and therapeutic efficiency in cancer chemotherapy. In the study, silymarin(SLM) and metformin (Met) were co-loaded into mesoporous silica nanoparticles (MSNs) and evaluated the synergistic inhibitory effect of these natural herbal compound in improving chemotherapeutic efficiency against MCF7MX and MCF7 human breast cancer cells. Nanoparticles have been synthesized and characterized by FTIR, BET, TEM, SEM, and X-ray diffraction. Drug loading capacity and release determined. The both single and combined form of SLM and Met (free and loaded MSN) were used for MTT assay, colony formation and real time-PCR in cellular study. The synthesis MSN were uniformity in size and shape with particle size of approximately 100 nm and pore size of approximately 2 nm. The Met-MSNs IC30, SLM -MSNs IC50 and dual-drug loaded MSNs IC50 were much lower than of free-Met IC30, free-SLM IC50 and free Met-SLM IC50 MCF7MX and MCF7cells. The co-loaded MSNs treated cells were increased sensitivity to mitoxantrone with the inhibition of BCRP mRNA expressions and could induce apoptosis in MCF7MX and MCF7 cells in comparison with other groups. Colony numbers were significantly reduced in comparison to with other groups in the co-loaded MSNs -treated cells ( ). Our results indicate that Nano-SLM enhances the anti-cancer effects of SLM against human breast cancer cells. The findings of the present study suggest that the anti-cancer effects of both metformin and silymarin enhances against breast cancer cells when MSNs are used as a drug delivery system.

Milk thistle nano-micelle formulation promotes cell cycle arrest and apoptosis in hepatocellular carcinoma cells through modulating miR-155-3p /SOCS2 /PHLDA1 signaling axis

BACKGROUND

Hepatocellular Carcinoma (HCC) is a prevalent form of liver cancer that causes significant mortality in numerous individuals worldwide. This study compared the effects of milk thistle (MT) and nano-milk thistle (N-MT) on the expression of the genes that participate in apoptosis and cell cycle pathways in Huh-7 and HepG2 cells.

METHODS

IC50 values of MT and N-MT were determined using the MTT assay. Huh-7 and HepG2 cell lines (containing mutant and wild-type TP53 gene, respectively) were incubated with MT and N-MT for 24h and 48h and the impact of MT and N-MT on the proliferation of these cell lines was evaluated through a comparative analysis. Cell cycle and apoptosis were assessed by flow cytometry after 24h and 48h treatment in the cell lines mentioned. Real-time PCR was used to analyze miR-155-3p, PHLDA1, SOCS2, TP53, P21, BAX, and BCL-2 expression in the cell lines that were being treated.

RESULTS

N-MT reduces cancer cell growth in a time and concentration-dependent manner, which is more toxic compared to MT. Huh-7 was observed to have IC50 values of 2.35 and 1.7 μg/ml at 24h and 48h, and HepG2 was observed to have IC50 values of 3.4 and 2.6 μg/ml at 24 and 48h, respectively. N-MT arrested Huh-7 and HepG2 cells in the Sub-G1 phase and induced apoptosis. N-MT led to a marked reduction in the expression of miR-155-3p and BCL-2 after 24h and 48h treatments. Conversely, PHLDA1, SOCS2, BAX, and P21 were upregulated in the treated cells compared to untreated cells, which suggests that milk thistle has the potential to regulate these genes. N-MT reduced the expression of TP53 in Huh-7 cells after mentioned time points, while there was a significant increase in the expression of the TP53 gene in HepG2 cells. No gene expression changes were observed in MT-treated cells after 24h and 48h.

CONCLUSION

N-MT can regulate cancer cell death by arresting cell cycle and inducing apoptosis. This occurs through the alteration of apoptotic genes expression. A reduction in the expression of miR-155-3p and increase in the expression of SOCS2 and PHLDA1 after N-MT treatment showed the correlation between miR-155-3p and PHLDA1/SOCS2 found in bioinformatics analysis. While N-MT increased TP53 expression in HepG2, reduced it in Huh-7. The findings indicate that N-MT can function intelligently in cancer cells and can be a helpful complement to cancer treatment.

Silymarin suppresses proliferation of human hepatocellular carcinoma cells under hypoxia through downregulation of the HIF-1α/VEGF pathway

BACKGROUND

Hypoxia is a significant feature of many solid tumors and can activate hypoxia-inducible factor 1α (HIF-1α)/vascular epidermal growth factor (VEGF) signaling pathway, which is closely related to the occurrence and development of primary liver cancer (PLC). Silymarin (SM) had been used as a traditional liver protective drug for decades. Recent studies have found that SM has chemopreventive and chemosensitizing effects on multiple cancers. In this study, we investigated the effects of SM on HIF-1α/VEGF signaling in human hepatocellular carcinoma cells under hypoxia conditions.

METHODS

HepG2 and Hep3B cells were divided into different experimental groups according to different culture conditions (aerobic or anaerobic) and the concentration of SM in the culture medium. The cellular proliferation, migration, invasion, colony formation, and apoptosis were observed by using methyl thiazolyl tetrazolium (MTT) assay, cell migration assay, in vitro invasion assay, soft agar colony formation assay, and Annexin V apoptosis assay, respectively. The cellular expressions of HIF-1α and VEGF were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) and western blot (WB) analyses.

RESULTS

SM reduced cellular proliferation, migration, invasion, and colony formation, but induced apoptosis in HepG2 and Hep3B cells under hypoxia conditions. The half inhibitory concentrations (IC50) of SM on HepG2 and Hep3B cells were 58.46 and 75.13 umol/L, respectively. SM also suppressed cellular expressions of HIF-1α and VEGF in HepG2 and Hep3B cells under hypoxia conditions at the mRNA and protein levels. All these effects of SM were dose dependent.

CONCLUSIONS

The inhibitory effect of SM on HepG2 and Hep3B cells under hypoxia is partially via downregulating HIF-1α/VEGF signaling, which may serve as a potential drug therapy target for liver cancer based on SM.

A systematic review of the protective effects of silymarin/silibinin against doxorubicin-induced cardiotoxicity

PURPOSE

Although doxorubicin chemotherapy is commonly applied for treating different malignant tumors, cardiotoxicity induced by this chemotherapeutic agent restricts its clinical use. The use of silymarin/silibinin may mitigate the doxorubicin-induced cardiac adverse effects. For this aim, the potential cardioprotective effects of silymarin/silibinin against the doxorubicin-induced cardiotoxicity were systematically reviewed.

METHODS

In this study, we performed a systematic search in accordance with PRISMA guideline for identifying all relevant studies on "the role of silymarin/silibinin against doxorubicin-induced cardiotoxicity" in different electronic databases up to June 2022. Sixty-one articles were obtained and screened based on the predefined inclusion and exclusion criteria. Thirteen eligible papers were finally included in this review.

RESULTS

According to the echocardiographic and electrocardiographic findings, the doxorubicin-treated groups presented a significant reduction in ejection fraction, tissue Doppler peak mitral annulus systolic velocity, and fractional shortening as well as bradycardia, prolongation of QT and QRS interval. However, these echocardiographic abnormalities were obviously improved in the silymarin plus doxorubicin groups. As well, the doxorubicin administration led to induce histopathological and biochemical changes in the cardiac cells/tissue; in contrast, the silymarin/silibinin co-administration could mitigate these induced alterations (for most of the cases).

CONCLUSION

According to the findings, it was found that the co-administration of silymarin/silibinin alleviates the doxorubicin-induced cardiac adverse effects. Silymarin/silibinin exerts its cardioprotective effects via antioxidant, anti-inflammatory, anti-apoptotic activities, and other mechanisms.

Silymarin in combination with ATRA enhances apoptosis induction in human acute promyelocytic NB4 cells

Although all-trans retinoic acid (ATRA) is an efficient pattern in acute promyelocytic leukemia (APL) therapy, further studies are required due to the extant clinical limitations of ATRA. It has been reported that Silymarin, an anti-cancer herbal substance extracted from milk thistle (Silybum marianum), is able to regulate apoptosis in various types of cancer cells through different mechanisms of action. This study investigated the apoptosis-inducing effect of Silymarin (SM) alone and in combination with ATRA on human acute promyelocytic NB4 cells. Examination using MTT assay indicated that SM treatment leads to growth inhibition in NB4 cells in a dose-dependent manner. The IC50 values of SM and ATRA were calculated 90 μM and 2 μM, respectively. Cell cycle analysis by flow cytometry revealed that a more increase in the sub-G1 phase (a sign of apoptosis) when cells were exposed to SM in combination with ATRA. The incidence of apoptosis was confirmed through Hoechst 33258 staining and Annexin V-FITC analysis. The results showed that Silymarin enhances ATRA-induced apoptosis. The flow cytometric analysis also indicated an enhancement in levels of ROS in the treated cells with both compounds. The real-time PCR illustrated that SM targets apoptosis by down-regulation in Survivin and Bcl-2 while up-regulation in Bax. The findings showed that the combination of the two compounds is more effective in the induction of apoptosis in NB4 cells. Molecular docking studies indicated that Sylibin, as a primary compound of the SM, binds to the BH3 domain of Bcl-2 and the BIR domain of Survivin with various affinities. Based on the findings, it seems that SM used alone and in combination with ATRA may be beneficial for inducing apoptosis in APL cells.

Role of Plant-Derived Flavonoids in Cancer Treatment

Flavonoids are polyphenolic phytochemicals, which occur naturally in plants and possess both anti-oxidant and pro-oxidant properties. Flavonoids are gaining increasing popularity in the pharmaceutical industry as healthy and cost-effective compounds. Flavonoids show beneficial pharmacological activities in the treatment and prevention of various types of diseases. They are natural and less toxic agents for cancer chemotherapy and radiotherapy via regulation of multiple cell signaling pathways and pro-oxidant effects. In this review, we have summarized the mechanisms of action of selected flavonoids, and their pharmacological implications and potential therapeutic applications in cancer therapy.

Unraveling the Peculiar Features of Mitochondrial Metabolism and Dynamics in Prostate Cancer

Prostate cancer (PCa) is the second leading cause of cancer deaths among men in Western countries. Mitochondria, the "powerhouse" of cells, undergo distinctive metabolic and structural dynamics in different types of cancer. PCa cells experience peculiar metabolic changes during their progression from normal epithelial cells to early-stage and, progressively, to late-stage cancer cells. Specifically, healthy cells display a truncated tricarboxylic acid (TCA) cycle and inefficient oxidative phosphorylation (OXPHOS) due to the high accumulation of zinc that impairs the activity of m-aconitase, the enzyme of the TCA cycle responsible for the oxidation of citrate. During the early phase of cancer development, intracellular zinc levels decrease leading to the reactivation of m-aconitase, TCA cycle and OXPHOS. PCa cells change their metabolic features again when progressing to the late stage of cancer. In particular, the Warburg effect was consistently shown to be the main metabolic feature of late-stage PCa cells. However, accumulating evidence sustains that both the TCA cycle and the OXPHOS pathway are still present and active in these cells. The androgen receptor axis as well as mutations in mitochondrial genes involved in metabolic rewiring were shown to play a key role in PCa cell metabolic reprogramming. Mitochondrial structural dynamics, such as biogenesis, fusion/fission and mitophagy, were also observed in PCa cells. In this review, we focus on the mitochondrial metabolic and structural dynamics occurring in PCa during tumor development and progression; their role as effective molecular targets for novel therapeutic strategies in PCa patients is also discussed.

Novel Insights into the Role of the Antioxidants in Prostate Pathology

To date, it is known that antioxidants protect cells from damage caused by oxidative stress and associated with pathological conditions. Several studies have established that inflammation is a state that anticipates the neoplastic transformation of the prostate. Although many experimental and clinical data have indicated the efficacy of antioxidants in preventing this form of cancer, the discrepant results, especially from recent large-scale randomized clinical trials, make it difficult to establish a real role for antioxidants in prostate tumor. Despite these concerns, clinical efficacy and safety data show that some antioxidants still hold promise for prostate cancer chemoprevention. Although more studies are needed, in this review, we briefly describe the most common antioxidants that have shown benefits in preclinical and clinical settings, focusing our attention on synthesizing the advances made so far in prostate cancer chemoprevention using antioxidants as interesting molecules for the challenges of future therapies.

Silymarin as a preventive or therapeutic measure for chemotherapy and radiotherapy-induced adverse reactions: a comprehensive review of preclinical and clinical data

PURPOSE

Thus far, silymarin has been examined in several studies for prevention or treatment of various chemotherapy or radiotherapy-induced adverse reactions. In this review, we try to collect all available human, animal, and pre-clinical data in this field.

METHODS

The search was done in Scopus, PubMed, Medline, and systematic reviews in the Cochrane database, using the following keywords: "Cancer," "Chemotherapy," "Radiotherapy," "Mucositis," "Nephrotoxicity," "Dermatitis," "Ototoxicity," "Cardiotoxicity," "Nephrotoxicity," "Hepatotoxicity," "Reproductive system," "Silybum marianum," "Milk thistle," and "Silymarin" and "Silybin." We included all relevant in vitro, in vivo, and human studies up to the date of publication.

RESULTS

Based on 64 included studies in this review, silymarin is considered a safe and well-tolerated compound, with no known clinical drug interaction. Notably, multiple adverse reactions of chemotherapeutic agents are effectively managed by its antioxidant, anti-apoptotic, anti-inflammatory, and anti-immunomodulatory properties. Clinical trials suggest that oral silymarin may be a promising adjuvant with cancer treatments, particularly against hepatotoxicity (n = 10), nephrotoxicity (n = 3), diarrhea (n = 1), and mucositis (n = 3), whereas its topical formulation can be particularly effective against radiodermatitis (n = 2) and hand-foot syndrome (HFS) (n = 1).

CONCLUSION

Further studies are required to determine the optimal dose, duration, and the best formulation of silymarin to prevent and/or manage chemotherapy and radiotherapy-induced complications.

Tannic Acid, A Hydrolysable Tannin, Prevents Transforming Growth Factor-β-Induced Epithelial-Mesenchymal Transition to Counteract Colorectal Tumor Growth

Despite the medico-surgical progress that has been made in the management of patients with colorectal cancer (CRC), the prognosis at five years remains poor. This resistance of cancer cells partly results from their phenotypic characteristics in connection with the epithelial-mesenchymal transition (EMT). In the present study, we have explored the ability of a polyphenol, tannic acid (TA), to counteract CRC cell proliferation and invasion through an action on the EMT. We highlight that TA decreases human SW480 and SW620 CRC cell and murine CT26 CRC cell viability, and TA inhibits their adhesion in the presence of important factors comprising the extracellular matrix, particularly in the presence of collagen type I and IV, and fibronectin. Moreover, these properties were associated with TA's ability to disrupt CRC cell migration and invasion, which are induced by transforming growth factor-β (TGF-β), as evidence in the video microscopy experiments showing that TA blocks the TGF-β1-induced migration of SW480 and CT26 cells. At the molecular level, TA promotes a reversal of the epithelial-mesenchymal transition by repressing the mesenchymal markers (i.e., Slug, Snail, ZEB1, and N-cadherin) and re-expressing the epithelial markers (i.e., E-cadherin and β-catenin). These effects could result from a disruption of the non-canonical signaling pathway that is induced by TGF-β1, where TA strongly decreases the phosphorylation of extracellular-signal regulated kinase ERK1/2, P38 and the AKT proteins that are well known to contribute to the EMT, the cell motility, and the acquisition of invasive properties by tumor cells. Very interestingly, a preclinical study of mice with subcutaneous murine tumor colon CT26 cells has shown that TA was able to significantly delay the growth of tumors without hepato- and nephrotoxicities.

Regulatory Networks, Management Approaches, and Emerging Treatments of Nonalcoholic Fatty Liver Disease

The pathogenesis of NAFLD is complex and diverse, involving multiple signaling pathways and cytokines from various organs. Hepatokines, stellakines, adipokines, and myokines secreted by hepatocytes, hepatic stellate cells, adipose tissue, and myocytes play an important role in the occurrence and development of nonalcoholic fatty liver disease (NAFLD). The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) contributes to the progression of NAFLD by mediating liver inflammation, immune response, hepatocyte death, and later compensatory proliferation. In this review, we first discuss the crosstalk and interaction between hepatokines, stellakines, adipokines, and myokines and NF-κB in NAFLD. The characterization of the crosstalk of NF-κB with these factors will provide a better understanding of the molecular mechanisms involved in the progression of NAFLD. In addition, we examine new expert management opinions for NAFLD and explore the therapeutic potential of silymarin in NAFLD/NASH.

Anticancer natural products targeting immune checkpoint protein network

Normal cells express surface proteins that bind to immune checkpoint proteins on immune cells to turn them off, whereby the immune system does not attack normal healthy cells. Cancer cells can also utilize this same protective mechanism by expressing surface proteins that can interact with checkpoint proteins on immune cells to overcome the immune surveillance. Immunotherapy is making the best use of the body's own immune system to reinforce anti-tumor responses. The most generally used immunotherapy is the control of immune checkpoints including the cytotoxic T lymphocyte-associated molecule 4 (CTLA-4), programmed cell deathreceptor 1 (PD-1), or programmed cell death ligand-1 (PD-L1). In spite of the clinical effectiveness of immune checkpoint inhibitors, the overall response rate still remains low. Therefore, there have been considerable efforts in searching for alternative immune checkpoint proteins that may work as new therapeutic targets for treatment of cancer. Recent studies have identified several additional novel immune checkpoint targets, including lymphocyte activation gene-3, T cell immunoglobulin and mucin-domain containing-3, T cell immunoglobulin and immunoreceptor tyrosine-based inhibition motif domain, V-domain Ig suppressor of T cell activation, B7 homolog 3 protein, B and T cell lymphocyte attenuator, and inducible T cell COStimulator. Natural compounds, especially those present in medicinal or dietary plants, have been investigated for their anti-tumor effects in various in vitro and in vivo models. Some phytochemicals exert anti-tumor activities based on immunoregulatioby blocking interaction between proteins involved in immune checkpoint signal transduction or regulating their expression/activity. Recently, synergistic anti-cancer effects of diverse phytochemicals with anti-PD-1/PD-L1 or anti-CTLA-4 monoclonal antibody drugs have been continuously reported. Considering an increasing attention to noteworthy therapeutic effects of immune checkpoint inhibitors in the cancer therapy, this review focuses on regulatory effects of selected phytochemicals on immune checkpoint protein network and their combinational effectiveness with immune checkpoint inhibitors targeting tumor cells.

Drug-herb combination therapy in cancer management

Cancer is the second leading cause of fatality all over the world. Various unwanted side effects are being reported with the use of conventional chemotherapy. The plant derived bioactive compounds are the prominent alternative medicinal approach for reduction of chemotherapy associated side effects. The data is collected from Pubmed, Sci-hub, Google scholar, and Research gate were systematically searched up to year 2020. Several herbal drugs have been investigated and found with grateful anti-cancer potentials hence, it can be used in combination with chemotherapy for the depletion of associated side-effects. Herbal drugs and their extracts contain a mixture of active ingredients, which show interactions within themselves and along with chemotherapeutic agents to show either synergistic or antagonistic therapeutic effects. Therefore, it is necessary to develop alternative treatment to control chemotherapy associated side-effects. In this review, we discussed some of the significant chemical compounds, which could be efficient against cancer. This review focuses on the different herbal drugs that play an important role in the treatment of cancer and its associated side-effects. This study aimed to evaluate the efficacy of herbal treatment in combination with chemotherapy for cancer treatment.

Countering Triple Negative Breast Cancer via Impeding Wnt/β-Catenin Signaling, a Phytotherapeutic Approach

Triple negative breast cancer (TNBC) is characterized as a heterogeneous disease with severe malignancy and high mortality. Aberrant Wnt/β-catenin signaling is responsible for self-renewal and mammosphere generation, metastasis and resistance to apoptosis and chemotherapy in TNBC. Nonetheless, in the absence of a targeted therapy, chemotherapy is regarded as the exclusive treatment strategy for the treatment of TNBC. This review aims to provide an unprecedented overview of the plants and herbal derivatives which repress the progression of TNBC through prohibiting the Wnt/β-catenin pathway. Herbal medicine extracts and bioactive compounds (alkaloids, retinoids. flavonoids, terpenes, carotenoids and lignans) alone, in combination with each other and/or with chemotherapy agents could interrupt the various steps of Wnt/β-catenin signaling, i.e., WNT, FZD, LRP, GSK3β, Dsh, APC, β-catenin and TCF/LEF. These phytotherapy agents diminish proliferation, metastasis, breast cancer stem cell self-renewal and induce apoptosis in cell and animal models of TNBC through the down-expression of the downstream target genes of Wnt signaling. Some of the herbal derivatives simultaneously impede Wnt/β-catenin signaling and other overactive pathways in triple negative breast cancer, including: mTORC1; ER stress and SATB1 signaling. The herbal remedies and their bioactive ingredients perform essential roles in the treatment of the very fatal TNBC via repression of Wnt/β-catenin signaling.

How Should the Worldwide Knowledge of Traditional Cancer Healing Be Integrated with Herbs and Mushrooms into Modern Molecular Pharmacology?

Traditional herbal medicine (THM) is a “core” from which modern medicine has evolved over time. Besides this, one third of people worldwide have no access to modern medicine and rely only on traditional medicine. To date, drugs of plant origin, or their derivates (paclitaxel, vinblastine, vincristine, vinorelbine, etoposide, camptothecin, topotecan, irinotecan, and omacetaxine), are very important in the therapy of malignancies and they are included in most chemotherapeutic regimes. To date, 391,000 plant and 14,000 mushroom species exist. Their medical and biochemical capabilities have not been studied in detail. In this review, we systematized the information about plants and mushrooms, as well as their active compounds with antitumor properties. Plants and mushrooms are divided based on the regions where they are used in ethnomedicine to treat malignancies. The majority of their active compounds with antineoplastic properties and mechanisms of action are described. Furthermore, on the basis of the available information, we divided them into two priority groups for research and for their potential of use in antitumor therapy. As there are many prerequisites and some examples how THM helps and strengthens modern medicine, finally, we discuss the positive points of THM and the management required to transform and integrate THM into the modern medicine practice.

Natural Products and their Derivatives as Immune Check Point Inhibitors: Targeting Cytokine/Chemokine Signalling in Cancer

Cancer immunotherapy is the new generation and widely accepted form of tumour treatment. It is, however, associated with exclusive challenges which include organ-specific inflammation, and single-target strategies. Therefore, approaches that can enhance the efficiency of existing immunotherapies and expand their indications are required for the further development of immunotherapy. Natural products and medicines are stated to have this desired effect on cancer immunotherapy (adoptive immune-cells therapy, cancer vaccines, and immune-check point inhibitors). They refurbish the immunosuppressed tumour microenvironment, which is the primary location of interaction of tumour cells with the host immune system. Various immune cell subsets, via interaction with cytokine/chemokine receptors, are recruited into this microenvironment, and these subsets have roles in tumour progression and treatment responsiveness. This review summarises cytokine/chemokine signalling, types of cancer immunotherapy and the herbal medicine-derived natural products targeting cytokine/chemokines and immune checkpoints. These natural compounds possess immunomodulatory activities and exert their anti-tumour effect by either blocking the interaction or modulating the expression of the proteins linked with immune checkpoint signaling pathways. Some compounds also show a synergistic effect in combination with existing monoclonal antibody drugs to reverse the tumour microenvironment. Additionally, we have also reported some studies about the derivatives and formulations used to overcome the limitations of natural forms. This review can provide important insights for directing future research.

Silybin suppresses ovarian cancer cell proliferation by inhibiting isocitrate dehydrogenase 1 activity

Metabolic reprogramming is a sign of malignant tumors, and targeting the metabolism of tumor cells has become a promising therapeutic approach. Here, we report that Silybin (a nontoxic flavonoid commonly used for liver protection) exhibits prominent anti‐tumor effects on human ovarian cancer cells. Treatment of an ovarian cancer cell line with Silybin interfered with glutamine metabolism and the tricarboxylic acid cycle. We applied the drug affinity responsive target stability approach to show that Silybin binds to isocitrate dehydrogenase 1 (IDH1). This combination leads to reduced phosphorylation of IDH1 and inhibits enzyme activity. IDH1 dysfunction significantly increases the ratio of NADP/NADPH in the cell, causing an increase in reactive oxygen species generation. Immunohistochemistry demonstrated that IDH1 was increased in ovarian cancer samples compared with normal para‐tumoral tissues. Xenograft murine experiments indicated that Silybin administered orally suppressed the growth of the tumor formed by ovarian cancer cells. In combination, our data strongly suggest that Silybin targets IDH1 in ovarian cancer cells and may be a novel treatment candidate.

Laccase-mediated synthesis of bioactive natural products and their analogues

Laccases are a class of multicopper oxidases that catalyse the one-electron oxidation of four equivalents of a reducing substrate, with the concomitant four-electron reduction of dioxygen to water. Typically, they catalyse many anabolic reactions, in which mostly phenolic metabolites were subjected to oxidative coupling. Alternatively, laccases catalyse the degradation or modification of biopolymers like lignin in catabolic processes. In recent years, laccases have proved valuable and green biocatalysts for synthesising compounds with therapeutic value, including antitumor, antibiotic, antimicrobial, and antioxidant agents. Further up to date applications include oxidative depolymerisation of lignin to gain new biomaterials and bioremediation processes of industrial waste. This review summarizes selected examples from the last decade's literature about the laccase-mediated synthesis of biologically active natural products and their analogues; these will include lignans and neolignans, dimeric stilbenoids, biflavonoids, biaryls and other compounds of potential interest for the pharmaceutical industry. In addition, a short section about applications of laccases in natural polymer modification has been included.

Untargeted metabolomics analysis of omeprazole-enhanced chemosensitivity to cisplatin in mice with non-small cell lung cancer

Drug resistance of tumors remains a major barrier in cisplatin (CDDP)-based chemotherapy. Omeprazole (OME) is often utilized during chemotherapy to alleviate gastrointestinal symptoms. In a previous investigation, we demonstrated a protective effect of OME against CDDP-induced kidney injury. To further establish whether OME could enhance chemosensitivity to CDDP and the underlying mechanisms, an in vivo tumor-bearing mouse model with CDDP-resistant A549 non-small cell lung cancer (A549/CDDP) was established in the current study. A high-performance liquid chromatography-time of flight mass spectrometry (HPLC-TOF/MS)-based untargeted metabolomics approach for tumor tissue and serum was employed to explore the mechanisms underlying the enhanced therapeutic effects of co-administration of CDDP and OME. Notably, tumor weights of mice in the CDDP + OME group were significantly decreased compared with those treated with CDDP alone. HE and TUNEL staining revealed more significant apoptosis of tumor cells in the group co-administered CDDP + OME relative to CDDP alone. Overexpression of multidrug resistance-associated protein 2 in CDDP-resistant tumors was significantly reversed upon treatment with CDDP + OME. PCA score plots of the groups co-treated with CDDP + OME were clearly separated from those treated with CDDP alone in metabolomics analysis for tumor and serum samples, clearly suggesting that co-administration of OME enhances the antitumor effect of CDDP. Subsequently, 10 and 7 metabolites in CDDP + OME group with significant changes in tumor and serum compared with CDDP group, respectively, were identified. Pathway analysis both in tumor and serum samples revealed regulation of the metabolism of purines, several amino acids and riboflavin in enhanced chemotherapy with both OME and CDDP. The collective findings provide beneficial novel insights into drug-drug interactions, which could improve the application of CDDP in clinical practice.

Silymarin inhibits the progression of Ehrlich solid tumor via targeting molecular pathways of cell death, proliferation, angiogenesis, and metastasis in female mice

BACKGROUND

Plant-derived phytochemicals have been reported to exert anticancer activity. This study investigated the antitumor role of silymarin (Silybum marianum) (SMN) and its molecular targets in Ehrlich solid tumor xenografts in vivo.

METHODS AND RESULTS

Female Swiss albino mice were divided into three groups (of five animals each) that were engrafted with Ehrlich tumor (ET) cells with or without SMN treatment. The 3rd groups treated with DMSO only vehicle control group. A significant reduction in animal body mass and tumor volume/weight were observed in xenografted mice treated with SMN. SMN modulated oxidative stress in tumors while enhancing the antioxidant levels in mouse serum. SMN activated both mitochondrial and death receptor-related apoptosis pathways and induced cell cycle arrest, marked by a significant downregulation of cyclin D1 in SMN-treated tumors. Significant decreases in RNA content and protein expression levels of Ki-67 and proliferating cell nuclear antigen were observed in ET cells. Additionally, SMN downregulated vascular endothelial growth factor and nuclear factor-kappa B levels indicating anti-angiogenesis activity of this agent. SMN upregulated the expression of E-cadherin in tumor tissue suggesting, that SMN has potential ability to inhibit metastasis. Tumor tissue from SMN-treated animals showed a remarkable degeneration and reduction in the neoplastic cell density.

CONCLUSIONS

The anticancer effect was associated with apparent apoptosis in neoplastic cells with abundance of multifocal necrotic areas. SMN was found to inhibit ET growth via enhancing apoptosis, inhibition of cell division and reduction in angiogenesis in vivo. Hypothetical scheme of SMN antitumor effects (mechanism of signaling) in solid ET in vivo. SMN anticancer effect may be mediated by molecular mediators that affect proliferation, cell cycle activity, apoptotic pathways, angiogenesis, and metastasis.

Milk thistle (Silybum marianum (L.)Gaertn.): An overview about its pharmacology and medicinal uses with an emphasis on oral diseases

BACKGROUND

Milk thistle, a medicinal plant, has different uses and benefits. Pathologies of the oral cavity manifest as different diseases with various therapeutic options. The main phytochemical extract of the milk thistle plant is silymarin. It has optimistic, protective, and therapeutic properties. However, evidence about the role of milk thistle extracts in oral diseases is lacking.

HIGHLIGHT

The pharmacology of milk thistle was overviewed. The role of the plant in some systemic diseases was reviewed. Furthermore, its role in various oral diseases was discussed. The presented articles described such effects in the context of periodontal disease, dental caries, oral candidiasis, oral lichen planus, oral cancer, and oral mucositis. Results on the promising effects of milk thistle extracts with a preference for silymarin were presented from different research designs. A summary of the previously used doses and the currently available pharmaceutical products was proposed for future research.

CONCLUSION

Milk thistle has antioxidant, anti-inflammatory, anticancer, antifungal, immunomodulatory, and other properties. The evidence from human research about the role of milk thistle in oral diseases is limited. Further studies, particularly clinical trials, to test milk thistle either as a potential treatment modality or a supplementary therapy for oral diseases on higher levels would be useful in the future.

Novel molecules as the emerging trends in cancer treatment: an update

As per World Health Organization cancer remains as a leading killer disease causing nearly 10 million deaths in 2020. Since the burden of cancer increases worldwide, warranting an urgent search for anti-cancer compounds from natural sources. Secondary metabolites from plants, marine organisms exhibit a novel chemical and structural diversity holding a great promise as therapeutics in cancer treatment. These natural metabolites target only the cancer cells and the normal healthy cells are left unharmed. In the emerging trends of cancer treatment, the natural bioactive compounds have long become a part of cancer chemotherapy. In this review, we have tried to compile about eight bioactive compounds from plant origin viz. combretastatin, ginsenoside, lycopene, quercetin, resveratrol, silymarin, sulforaphane and withaferin A, four marine-derived compounds viz. bryostatins, dolastatins, eribulin, plitidepsin and three microorganisms viz. Clostridium, Mycobacterium bovis and Streptococcus pyogenes with their well-established anticancer potential, mechanism of action and clinical establishments are presented.

Dual inhibition of reactive oxygen species and spleen tyrosine kinase as a therapeutic strategy in liver fibrosis

Hepatic stellate cells (HSCs) play key roles in liver fibrosis (LF) and hepatocellular carcinoma (HCC). We previously reported that spleen tyrosine kinase (SYK) is critical for HSCs activation, however, the mechanisms are insufficiently understood. In the present study, we found that SYK facilitated autophagy to promote HSCs activation by enhancing reactive oxygen species (ROS) generation. However, SYK inhibitor GS-9973 could efficiently reduce HSCs ROS generation in vitro but not in vivo. Mechanistically, hepatocytes (HCs) would release ROS outside and then diffuse into HSCs to promote autophagy and activation in vitro in the context of inflammation. We then further examined the ROS contents in liver sections and primary liver cells of carbon tetrachloride (CCl4) induced mice treated with or without different doses of Silybin, a natural compound characterized by a well-established antioxidant and hepatoprotective properties, and found that ROS intensities in both liver sections and their deprived primary cells were efficiently inhibited in a dose-dependent fashion. Lastly, we evaluated the rational combination of Silybin and GS-9973 in the treatment of CCl4 induced mice and found that this combination is well tolerated and acts synergistically against HSCs activity, LF and HCC. The combinational use of Silybin and GS-9973 could be a promising therapeutic strategy in patients suffering from LF and even HCC.

Flavonoids against non-physiologic inflammation attributed to cancer initiation, development, and progression—3PM pathways

Inflammation is an essential pillar of the immune defense. On the other hand, chronic inflammation is considered a hallmark of cancer initiation and progression. Chronic inflammation demonstrates a potential to induce complex changes at molecular, cellular, and organ levels including but not restricted to the stagnation and impairment of healing processes, uncontrolled production of aggressive ROS/RNS, triggered DNA mutations and damage, compromised efficacy of the DNA repair machinery, significantly upregulated cytokine/chemokine release and associated patho-physiologic protein synthesis, activated signaling pathways involved in carcinogenesis and tumor progression, abnormal tissue remodeling, and created pre-metastatic niches, among others. The anti-inflammatory activities of flavonoids demonstrate clinically relevant potential as preventive and therapeutic agents to improve individual outcomes in diseases linked to the low-grade systemic and chronic inflammation, including cancers. To this end, flavonoids are potent modulators of pro-inflammatory gene expression being, therefore, of great interest as agents selectively suppressing molecular targets within pro-inflammatory pathways. This paper provides in-depth analysis of anti-inflammatory properties of flavonoids, highlights corresponding mechanisms and targeted molecular pathways, and proposes potential treatment models for multi-level cancer prevention in the framework of predictive, preventive, and personalized medicine (PPPM / 3PM). To this end, individualized profiling and patient stratification are essential for implementing targeted anti-inflammatory approaches. Most prominent examples are presented for the proposed application of flavonoid-conducted anti-inflammatory treatments in overall cancer management.

Synergistic anti-cancer effects of silibinin-etoposide combination against human breast carcinoma MCF-7 and MDA-MB-231 cell lines

OBJECTIVES

Recently, there is a significant focus on combination chemotherapy for cancer using a cytotoxic drug and a phytochemical compound. We investigated the effect of silibinin on etoposide-induced apoptosis in MCF-7 and MDA-MB-231 breast carcinoma cell lines.

MATERIALS AND METHODS

The cytotoxic effects of silibinin and etoposide were determined using MTT assay after 24 and 48 hr incubation with these drugs individually and combined. The mRNA expression of Bax and Bcl2, and protein levels of P53, phosphorylated p53 (P-P53), and P21 were determined using real-time PCR and western blot analysis, respectively. The caspase 9 activity was measured using an ELISA kit.

RESULTS

Silibinin and etoposide alone and combined significantly inhibit cell growth in a dose and time-dependent manner in both cell lines. The strongest synergistic effects in terms of MCF-7 cell growth inhibition [combination index (CI) = 0.066] were evident. The silibinin-etoposide combinations cause a much powerful apoptotic death (47% and 40%) compared with each compound individually in MCF-7 and MDA-MB 231 cells, respectively. Additionally, the silibinin-etoposide combinations significantly increased the expression of P53, P-P53, and P21 in MCF-7 cells. Neither silibinin nor etoposide individually increased the level of P53 and P-P53 in MDA-MB-231 cells, but both of them individually and combined increased the level of P21.

CONCLUSION

Since the silibinin-etoposide combination induces apoptosis in both cell lines with and without expression of p53, thus, it is suggested that this combination may be a successful therapeutic strategy for breast cancer regardless of P53 status.

Lung Cancer Management with Silibinin: A Historical and Translational Perspective

The flavonolignan silibinin, the major bioactive component of the silymarin extract of Silybum marianum (milk thistle) seeds, is gaining traction as a novel anti-cancer therapeutic. Here, we review the historical developments that have laid the groundwork for the evaluation of silibinin as a chemopreventive and therapeutic agent in human lung cancer, including translational insights into its mechanism of action to control the aggressive behavior of lung carcinoma subtypes prone to metastasis. First, we summarize the evidence from chemically induced primary lung tumors supporting a role for silibinin in lung cancer prevention. Second, we reassess the preclinical and clinical evidence on the effectiveness of silibinin against drug resistance and brain metastasis traits of lung carcinomas. Third, we revisit the transcription factor STAT3 as a central tumor-cell intrinsic and microenvironmental target of silibinin in primary lung tumors and brain metastasis. Finally, by unraveling the selective vulnerability of silibinin-treated tumor cells to drugs using CRISPR-based chemosensitivity screenings (e.g., the hexosamine biosynthesis pathway inhibitor azaserine), we illustrate how the therapeutic use of silibinin against targetable weaknesses might be capitalized in specific lung cancer subtypes (e.g., KRAS/STK11 co-mutant tumors). Forthcoming studies should take up the challenge of developing silibinin and/or next-generation silibinin derivatives as novel lung cancer-preventive and therapeutic biomolecules.

Triglyceride-induced cardiac lipotoxicity is mitigated by Silybum marianum

BACKGROUND AND AIMS

Silybum marianum (SM) is an herbal product with cytoprotective and antioxidant properties. We have previously demonstrated that SM ameliorates ventricular remodeling and improves cardiac performance. Here, we evaluated whether SM could exert beneficial effects against cardiac lipotoxicity in a pig model of closed-chest myocardial infarction (MI).

METHODS

Study 1 investigated the effect of SM administration on lipid profile and any potential SM-related adverse effects. Animals received SM or placebo during 10 days and were afterward sacrificed. Study 2 evaluated the effectiveness of SM daily administration in reducing cardiac lipotoxicity in animals subjected to a 1.5h myocardial infarction (MI), who were subsequently reperfused for 2.5h and euthanized or kept under study for three weeks and then sacrificed.

RESULTS

Animals administered a 10-day SM regime presented a sharp decline in plasma triglyceride levels vs. controls, with no other modifications in lipid profile. The decrease in triglyceride concentration was accompanied by a marked reduction in triglyceride intestinal absorption and glycoprotein-P expression. Three weeks post-MI the triglyceride content in the ischemic myocardium of the SM-treated animals was significantly lower than in the ischemic myocardium of placebo-controls. This effect was associated with an enhanced cardiac expression of PPARγ and triglyceride clearance receptors. This long-term SM-administration induced a lower expression of lipid receptors in subcutaneous adipose tissue. No SM-related side-effects were registered.

CONCLUSION

SM administration reduces plasma triglyceride levels through attenuation of triglyceride intestinal absorption and modulates cardiac lipotoxicity in the ischemic myocardium, likely contributing to improve ventricular remodeling.

Interaction of silymarin components and their sulfate metabolites with human serum albumin and cytochrome P450 (2C9, 2C19, 2D6, and 3A4) enzymes

Silymarin is a mixture of flavonolignans isolated from the fruit of milk thistle (Silybum marianum (L.) Gaertner). Milk thistle extract is the active ingredient of several medications and dietary supplements to treat liver injury/diseases. After the oral administration, flavonolignans are extensively biotransformed, resulting in the formation of sulfate and/or glucuronide metabolites. Previous studies demonstrated that silymarin components form stable complexes with serum albumin and can inhibit certain cytochrome P450 (CYP) enzymes. Nevertheless, in most of these investigations, silybin was tested; while no or only limited information is available regarding other silymarin components and metabolites. In this study, the interactions of five silymarin components (silybin A, silybin B, isosilybin A, silychristin, and 2,3-dehydrosilychristin) and their sulfate metabolites were examined with human serum albumin and CYP (2C9, 2C19, 2D6, and 3A4) enzymes. Our results demonstrate that each compound tested forms stable complexes with albumin, and certain silymarin components/metabolites can inhibit CYP enzymes. Most of the sulfate conjugates were less potent inhibitors of CYP enzymes, but 2,3-dehydrosilychristin-19-O-sulfate showed the strongest inhibitory effect on CYP3A4. Based on these observations, the simultaneous administration of high dose silymarin with medications should be carefully considered, because milk thistle flavonolignans and/or their sulfate metabolites may interfere with drug therapy.

Bioconversion of Callus-Produced Precursors to Silymarin Derivatives in Silybum marianum Leaves for the Production of Bioactive Compounds

The present study aimed to investigate the enzymatic potential of Silybum marianum leaves to bioconvert phenolic acids produced in S. marianum callus into silymarin derivatives as chemopreventive agent. Here we demonstrate that despite the fact that leaves of S. marianum did not accumulate silymarin themselves, expanding leaves had the full capacity to convert di-caffeoylquinic acid to silymarin complex. This was proven by HPLC separations coupled with electrospray ionization mass spectrometry (ESI-MS) analysis. Soaking the leaf discs with S. marianum callus extract for different times revealed that silymarin derivatives had been formed at high yield after 16 h. Bioconverted products displayed the same retention time and the same mass spectra (MS or MS/MS) as standard silymarin. Bioconversion was achieved only when using leaves of a specific age, as both very young and old leaves failed to produce silymarin from callus extract. Only medium leaves had the metabolic capacity to convert callus components into silymarin. The results revealed higher activities of enzymes of the phenylpropanoid pathway in medium leaves than in young and old leaves. It is concluded that cotyledon-derived callus efficiently produces compounds that can be bio-converted to flavonolignans in leaves tissue of S. marianum.

Plasma-Conditioned Liquids as Anticancer Therapies In Vivo: Current State and Future Directions

Plasma-conditioned liquids (PCL) are gaining increasing attention in the medical field, especially in oncology, and translation to the clinics is advancing on a good path. This emerging technology involving cold plasmas has great potential as a therapeutic approach in cancer diseases, as PCL have been shown to selectively kill cancer cells by triggering apoptotic mechanisms without damaging healthy cells. In this context, PCL can be injected near the tumor or intratumorally, thereby allowing the treatment of malignant tumors located in internal organs that are not accessible for direct cold atmospheric plasma (CAP) treatment. Therefore, PCL constitutes a very interesting and minimally invasive alternative to direct CAP treatment in cancer therapy, avoiding surgeries and allowing multiple local administrations. As the field advances, it is progressively moving to the evaluation of the therapeutic effects of PCL in in vivo scenarios. Exciting developments are pushing forward the clinical translation of this novel therapy. However, there is still room for research, as the quantification and identification of reactive oxygen and nitrogen species (RONS) in in vivo conditions is not yet clarified, dosage regimens are highly variable among studies, and other more relevant in vivo models could be used. In this context, this work aims to present a critical review of the state of the field of PCL as anticancer agents applied in in vivo studies.

Anticancer activity of Vicenin-2 against 7,12 dimethylbenz[a]anthracene-induced buccal pouch carcinoma in hamsters

Buccal mucosa carcinoma is a significant cause of death in developing nations. Vicenin-2 is a significant bioactive compound found in Ocimum sanctum Linn or Tulsi that possesses several pharmacologic properties. Our focus is to understand the possible impact of Vicenin-2 on 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters. Buccal carcinoma was induced by treatment with carcinogenic DMBA, three times a week for 14 weeks. We determined 100% tumor incidence, abnormal tumor volume, inclined tumor burden, and deduced body weight in DMBA-induced oral squamous cell carcinoma (OSCC) hamsters. The upregulation of cytokine levels (interleukin [IL]-6, IL-1β, and tumor necrosis factor-alpha [TNF-α]) was observed in DMBA-induced OSCC hamsters. Moreover, dysplastic, hyperplastic, and squamous cell carcinoma was identified in the DMBA-induced OSCC hamsters. The diminished activities of lipid peroxidation and enzymatic/nonenzymatic antioxidants were observed in DMBA-induced hamsters. Furthermore, the high expression of proliferating cell nuclear antigen (PCNA), Cyclin-D1, and Bcl-2, and attenuated Bax expression were observed in DMBA-induced hamsters. Our study results explored that Vicenin-2 (30 mg/kg) treated with DMBA-brushed hamsters averted tumor incidence, improved the antioxidant status, and inhibited lipid peroxidation. Moreover, Vicenin-2 inhibited the immunohistochemical expression of PCNA, Cyclin-D1, and Bcl-2, and significantly restored apoptotic Bax levels. The Vicenin-2 treatment prevents the lesion formation in the oral epithelium of the DMBA-induced hamsters. The Vicenin-2 treatment potentially halts the proinflammatory cytokines (IL-6, IL-1β, and TNF-α) production in OSCC hamsters. Thus, we proved that Vicenin-2 prevents DMBA-induced buccal carcinogenesis in hamsters via improving antioxidants by modulating apoptotic and cytokines signaling pathways.

Path of Silibinin from diet to medicine: A dietary polyphenolic flavonoid having potential anti-cancer therapeutic significance

In the last few decades, targeting cancer by the use of dietary phytochemicals has gained enormous attention. The plausible reason and believe or mind set behind this fact is attributed to either lesser or no side effects of natural compounds as compared to the modern chemotherapeutics, or due to their conventional use as dietary components by mankind for thousands of years. Silibinin is a naturally derived polyphenol (a flavonolignans), possess following biochemical features; molecular formula C₂₅H₂₂O₁₀, Molar mass: 482.44 g/mol, Boiling point 793 °C, with strikingly high antioxidant and anti-tumorigenic properties. The anti-cancer properties of Silibinin are determined by a variety of cellular pathways which include induction of apoptosis, cell cycle arrest, inhibition of angiogenesis and metastasis. In addition, Silibinin controls modulation of the expression of aberrant miRNAs, inflammatory response, and synergism with existing anti-cancer drugs. Therefore, modulation of a vast array of cellular responses and homeostatic aspects makes Silibinin an attractive chemotherapeutic agent. However, like other polyphenols, the major hurdle to declare Silibinin a translational chemotherapeutic agent, is its lesser bioavailability. After summarizing the chemistry and metabolic aspects of Silibinin, this extensive review focuses on functional aspects governed by Silibinin in chemoprevention with an ultimate goal of summarizing the evidence supporting the chemopreventive potential of Silibinin and clinical trials that are currently ongoing, at a single platform.

Stable Isotope Tracing Metabolomics to Investigate the Metabolic Activity of Bioactive Compounds for Cancer Prevention and Treatment

A major hallmark of cancer is the metabolic reprogramming of cancer cells to fuel tumor growth and proliferation. Various plant-derived bioactive compounds efficiently target the metabolic vulnerabilities of cancer cells and exhibit potential as emerging therapeutic agents. Due to their safety and common use as dietary components, they are also ideal for cancer prevention. However, to render their use as efficient as possible, the mechanism of action of these phytochemicals needs to be well characterized. Stable isotope tracing is an essential technology to study the molecular mechanisms by which nutraceuticals modulate and target cancer metabolism. The use of positionally labeled tracers as exogenous nutrients and the monitoring of their downstream metabolites labeling patterns enable the analysis of the specific metabolic pathway activity, via the relative production and consumption of the labeled metabolites. Although stable isotope tracing metabolomics is a powerful tool to investigate the molecular activity of bioactive compounds as well as to design synergistic nutraceutical combinations, this methodology is still underutilized. This review aims to investigate the research efforts and potentials surrounding the use of stable isotope tracing metabolomics to examine the metabolic alterations mediated by bioactive compounds in cancer.

Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis

In recent years, and even more since its legalization in several jurisdictions, cannabis and the endocannabinoid system have received an increasing amount of interest related to their potential exploitation in clinical settings. Cannabinoids have been suggested and shown to be effective in the treatment of various conditions. In cancer, the endocannabinoid system is altered in numerous types of tumours and can relate to cancer prognosis and disease outcome. Additionally, cannabinoids display anticancer effects in several models by suppressing the proliferation, migration and/or invasion of cancer cells, as well as tumour angiogenesis. However, the therapeutic use of cannabinoids is currently limited to the treatment of symptoms and pain associated with chemotherapy, while their potential use as cytotoxic drugs in chemotherapy still requires validation in patients. Along with cannabinoids, cannabis contains several other compounds that have also been shown to exert anti-tumorigenic actions. The potential anti-cancer effects of cannabinoids, terpenes and flavonoids, present in cannabis, are explored in this literature review.

Silymarin and Derivatives: From Biosynthesis to Health Benefits

The past decade has been marked by an intense scientific interest in the use of compounds or micronutrients of natural origin and their potential effects on human health, both from researchers and industry [...].