3,3'-Diindolylmethane enhances apoptosis in docetaxel-treated breast cancer cells by generation of reactive oxygen species

PSMA-targeted combination brusatol and docetaxel nanotherapeutics for the treatment of prostate cancer

Active targeting to cancer involves exploiting specific interactions between receptors on the surface of cancer cells and targeting moieties conjugated to the surface of vectors such that site-specific delivery is achieved. Prostate specific membrane antigen (PSMA) has proved to be an excellent target for active targeting to prostate cancer. We report the synthesis and use of a PSMA-specific ligand (Glu-NH-CO-NH-Lys) for the site-specific delivery of brusatol- and docetaxel-loaded poly(lactide-co-glycolide) (PLGA) nanoparticles to prostate cancer. The PSMA targeting ligand covalently linked to PLGA-PEG3400 was blended with methoxyPEG-PLGA to prepare brusatol- and docetaxel-loaded nanoparticles with different surface densities of the targeting ligand. Flow cytometry was used to evaluate the impact of different surface densities of the PSMA targeting ligand in LNCaP prostate cancer cells at 15 min and 2 h. Cytotoxicity evaluations of the targeted nanoparticles reveal differences based on PSMA expression in PC-3 and LNCaP cells. In addition, levels of reactive oxygen species (ROS) were measured using the fluorescent indicator, H2DCFDA, by flow cytometry. PSMA-targeted nanoparticles loaded with docetaxel and brusatol showed increased ROS generation in LNCaP cells compared to PC-3 at different time points. Furthermore, the targeted nanoparticles were evaluated in male athymic BALB/c mice implanted with PSMA-producing LNCaP cell tumors. Evaluation of the percent relative tumor volume show that brusatol-containing nanoparticles show great promise in inhibiting tumor growth. Our data also suggest that the dual drug-loaded targeted nanoparticle platform improves the efficacy of docetaxel in male athymic BALB/c mice implanted with PSMA-producing LNCaP cell tumors.

Epigenetics and the role of nutraceuticals in health and disease

In the post-genomic era, the data provided by complete genome sequencing could not answer several fundamental questions about the causes of many noninfectious diseases, diagnostic biomarkers, and novel therapeutic approaches. The rapidly expanding understanding of epigenetic mechanisms, as well as widespread acceptance of their hypothesized role in disease induction, facilitated the development of a number of novel diagnostic markers and therapeutic concepts. Epigenetic aberrations are reversible in nature, which enables the treatment of serious incurable diseases. Therefore, the interest in epigenetic modulatory effects has increased over the last decade, so about 60,000 publications discussing the expression of epigenetics could be detected in the PubMed database. Out of these, 58,442 were published alone in the last 10 years, including 17,672 reviews (69 historical articles), 314 clinical trials, 202 case reports, 197 meta-analyses, 156 letters to the editor, 108 randomized controlled trials, 87 observation studies, 40 book chapters, 22 published lectures, and 2 clinical trial protocols. The remaining publications are either miscellaneous or a mixture of the previously mentioned items. According to the species and gender, the publications included 44,589 human studies (17,106 females, 14,509 males, and the gender is not mentioned in the remaining papers) and 30,253 animal studies. In the present work, the role of epigenetic modulations in health and disease and the influencing factors in epigenetics are discussed.

Diindolylmethane Promotes Metabolic Crisis and Enhances the Efficacy of Centchroman in Breast Cancer: A 1H NMR-Based Approach

Diindolylmethane (DIM) is a key metabolite of indole-3-carbinol found in cruciferous vegetables such as broccoli, cauliflower, and cabbage. DIM has been known for its anti-cancerous activity through various mechanisms. Most cancer cells, including triple-negative breast cancer (TNBC), adapt distinct metabolic reprogramming for rapid growth and proliferation. Hence, targeting metabolic dysregulation may provide a favorable therapeutic condition for the treatment of TNBC. Earlier, we found that DIM increases the intracellular accumulation of Centchroman (CC), a potential anticancer agent, thereby enhancing the therapeutic potential of CC against breast cancer. However, the role of DIM in regulating TNBC cellular metabolism remains unknown. In the current study, we investigated the potential therapeutic interventions of DIM in TNBC and its metabolic reprogramming in enhancing the efficacy of CC. We found that DIM induced metabolic catastrophe in TNBC cells by regulating aerobic glycolysis and intermediate metabolism. Further, the DIM and CC combination significantly inhibited the TNBC tumor growth in the 4T1-syngeneic model. The inhibition of tumor growth was associated with the downregulation of key aerobic glycolysis mediators such as PKM2, GLUT1, and hypoxia-inducible factor 1α (HIF-1α). This is a first-of-a-kind investigation linking DIM with aerobic glycolysis regulation and enhancing the treatment efficacy of CC against TNBC. Therefore, these findings suggest that DIM-based nutraceuticals and functional foods can be developed as adjuvant therapy for treating metabolically dysregulated TNBC.

3,3'-Diindolylmethane induces apoptosis and autophagy in fission yeast

3,3'-Diindolylmethane (DIM) is a compound derived from the digestion of indole-3-carbinol, found in the broccoli family. It induces apoptosis and autophagy in some types of human cancer. DIM extends lifespan in the fission yeast Schizosaccharomyces pombe. The mechanisms by which DIM induces apoptosis and autophagy in humans and expands lifespan in fission yeasts are not fully understood. Here, we show that DIM induces apoptosis and autophagy in log-phase cells, which is dose-dependent in fission yeast. A high concentration of DIM disrupted the nuclear envelope (NE) structure and induced chromosome condensation at an early time point. In contrast, a low concentration of DIM induced autophagy but did not disrupt NE structure. The mutant defective in autophagy was more sensitive to a low concentration of DIM, demonstrating that the autophagic pathway contributes to the survival of cells against DIM. Moreover, our results showed that the lem2 mutant is more sensitive to DIM. NE in the lem2 mutant was disrupted even at the low concentration of DIM. Our results demonstrate that the autophagic pathway and NE integrity are important to maintain viability in the presence of a low concentration of DIM. The mechanism of apoptosis and autophagy induction by DIM might be conserved in fission yeast and humans. Further studies will contribute to the understanding of the mechanism of apoptosis and autophagy by DIM in fission yeast and humans.

Concise Nanoplatform of Phycocyanin Nanoparticle Loaded with Docetaxel for Synergetic Chemo-sonodynamic Antitumor Therapy

Combined chemotherapy and sonodynamic therapy (chemo-SDT) based on the nanoplatform/nanocarrier is a potential antitumor strategy that has shown higher therapeutic efficacy than any monotherapy. Therefore, a safe and effective multifunctional system with a concise design and simple preparation process is urgently needed. In this work, by using a one-step cross-linking method, a multifunctional nanosystem, which employs phycocyanin nanoparticles (PCNPs) as a nanocarrier to deliver the chemotherapy drug docetaxel (DTX) and a nanosonosensitizer to generate reactive oxygen species (ROS), was prepared and evaluated (PCNP-DTX). Under low-intensity ultrasound irradiation, PCNP-DTX retained the ROS generation ability of phycocyanin and caused the destruction of mitochondrial potential. PCNP was also revealed to be an acidic and ultrasound-sensitive carrier with good biocompatibility. In addition to its cumulation behavior in tumors, PCNP can achieve tumor-targeted delivery and release of DTX. PCNP-DTX has also been proven to have a significant chemo-SDT synergy effect when low-intensity ultrasound was applied, showing enhanced antitumor activity both in vitro and in vivo. This study provides a concise yet promising nanoplatform based on the natural protein phycocyanin for achieving an effective, targeted, and synergetic chemo-SDT for antitumor therapy.

Dietary bioactive diindolylmethane enhances the therapeutic efficacy of centchroman in breast cancer cells by regulating ABCB1/P-gp efflux transporter

Overexpression of drug efflux transporters is commonly associated with multidrug-resistance in cancer therapy. Here for the first time, we investigated the ability of diindolylmethane (DIM), a dietary bioactive rich in cruciferous vegetables, in enhancing the efficacy of Centchroman (CC) by modulating the drug efflux transporters in human breast cancer cells. CC is a selective estrogen receptor modulator, having promising therapeutic efficacy against breast cancer. The combination of DIM and CC synergistically inhibited cell proliferation and induced apoptosis in breast cancer cells. This novel combination has also hindered the stemness of human breast cancer cells. Molecular docking analysis revealed that DIM had shown a strong binding affinity with the substrate-binding sites of ABCB1 (P-gp) and ABCC1 (MRP1) drug-efflux transporters. DIM has increased the intracellular accumulation of Hoechst and Calcein, the substrates of P-gp and MRP1, respectively, in breast cancer cells. Further, DIM stimulates P-gp ATPase activity, which indicates that DIM binds at the substrate-binding domain of P-gp, and thereby inhibits its efflux activity. Intriguingly, DIM enhanced the intracellular concentration of CC by inhibiting the P-gp and MRP1 expression as well as activity. The intracellular retaining of CC has increased its efficacy against breast cancer. Overall, DIM, a dietary bioactive, enhances the anticancer efficiency of CC through modulation of drug efflux ABC-transporters in breast cancer cells. Therefore, DIM-based nutraceuticals and functional foods can be developed as adjuvant therapy against human breast cancer.

Redox imbalance induced by docetaxel in the neuroblastoma SH-SY5Y cells: a study of docetaxel-induced neuronal damage

Objectives

In cancer survivors, chemotherapy-associated adverse neurological effects are described as side effects in non-targeted tissue. We investigated the role of redox-imbalance in neuronal damage by a relative low dose of Docetaxel (DTX).

Methods

The neuroblastoma cells (SH-SY5Y cells) were exposed to DTX at a dose of 1.25 nM for 6 h. Antioxidant defenses (i.e. ascorbic acid, glutathione, and catalase) and lipid oxidation products (i.e. F₂-isoprostanes) were evaluated. To investigate cell ultrastructure and tubulin localisation, transmission electron microscopy (TEM) and immunofluorescence techniques were applied.

Results

In the SH-SY5Y cells, DTX induced a significant reduction of total glutathione (P < 0.001) and ascorbic acid (P < 0.05), and an increase in both total F₂-Isoprostanes (P < 0.05) and catalase activity (P < 0.05), as compared to untreated cells. Additionally, TEM showed a significant increase in cells with apoptotic characteristics. Immunolocalisation of tubulin showed a compromised cytoskeletal organisation.

Discussion

The investigated sublethal dose of DTX, to which non-targeted cells may be exposed throughout the duration of chemotherapy treatment, induces a redox imbalance resulting in a specific modulation of the antioxidant response. This study provides new insights into DTX-induced cellular mechanisms useful for evaluating whether the concomitant use of antioxidants associated with chemotherapy mitigates chemotherapy side effects in cancer survivors.

3,3'-diindolylmethane exerts antiproliferation and apoptosis induction by TRAF2-p38 axis in gastric cancer

3,3'-diindolylmethane (DIM), an active phytochemical derivative extracted from cruciferous vegetables, possesses anticancer effects. However, the underlying anticancer mechanism of DIM in gastric cancer remains unknown. Tumor necrosis factor (TNF) receptor-associated factor 2 (TRAF2), one of the signal transduction proteins, plays critical role in proliferation and apoptosis of human gastric cancer cells, but there are still lack of practical pharmacological modulators for potential clinical application. Here, we further explored the role of TRAF2 in inhibiting cell proliferation and inducing apoptosis by DIM in human gastric cancer BGC-823 and SGC-7901 cells. After treating BGC-823 and SGC-7901 cells with DIM for 24 h, cell proliferation, apoptosis and TRAF2-related protein were measured. Our findings showed that DIM inhibited the expressions of TRAF2, activated p-p38 and its downstream protein p-p53, which were paralleled with DIM-triggered cells proliferation, inhibition and apoptosis induction. These effects of DIM were reversed by TRAF2 overexpression or p38 mitogen-activated protein kinase (MAPK)-specific inhibitor (SB203580). Taken together, our data suggest that regulating TRAF2/p38 MAPK signaling pathway is essential for inhibiting gastric cancer proliferation and inducing apoptosis by DIM. These findings broaden the understanding of the pharmacological mechanism of DIM's action as a new modulator of TRAF2, and provide a new therapeutic target for human gastric cancer.

Mechanism for allicin to sensitize gastric cancer cells to chemotherapy

BACKGROUND

It is reported that diallyl trisulfide (DATS) can promote metaphase arrest of gastric cancer cells (GCC). We found that DATS can increase the expression of cyclin B1 (CCNB1), and many studies reported that the expression of CCNB1 decreased after metaphase arrest induced by drug treatment. Moreover, a few studies reported that overexpression of CCNB1 can promote the sensitivity of GCC to docetaxel (DOC). However, whether DATS promotes the sensitivity of GCC to DOC through overexpression of CCNB1 is still unclear.

AIM

To investigate the sensitization effect of allicin on GCC to chemotherapeutic drug DOC and the underlying mechanism.

METHODS

BGC823 cells at logarithmic growth phase were cultured in vitro. Flow cytometry was used to determine the effect of allicin on BGC823 cell proliferation to determine the optimal drug concentration and treatment duration. The proliferation and apoptosis of BGC823 cells in blank control cells, DATS treated cells, DOC treated cells, and DATS + DOC treated cells were analyzed by flow cytometry. The expression of CCNB1 was determined by Western blot to determine the role of CCNB1 in DATS-mediated sensitization of GCC to chemotherapy.

RESULTS

DATS can inhibit BGC823 cell proliferation, and the optimal contration and treatment duration were 25 mol/L and 12 hours, respectively. During the process of BGC823 cell proliferation, DATS induced the increase of CCNB1 expression. The apoptosis rate, G2/M cell ratio, and CCNB1 expression level in BGC823 cells treated with DOC alone, DATS alone, and DOC plus DATS were significantly higher than those in blank control cells (P < 0.05), and the effects in cells treated with DOC plus DATS were significantly higher than those in cells treated with DOC or DATS alone (P < 0.05).

CONCLUSION

DATS can inhibit the proliferation of BGC823 cells. DATS can synergistically increase the sensitivity of GCC to DOC chemotherapy via mechanisms possibly related to the increased expression of CCNB1 protein.

Mitochondrial oxidative stress-induced brain and hippocampus apoptosis decrease through modulation of caspase activity, Ca2+ influx and inflammatory cytokine molecular pathways in the docetaxel-treated mice by melatonin and selenium treatments

Docetaxel (DOCE) is widely used to treat several types of glioblastoma. Adverse effects DOCE seriously limit its clinical use in several tissues. Its side effects on brain cortex and hippocampus have not been clarified yet. Limited data indicated a protective effect of melatonin (MLT) and selenium (SELEN) on DOCE-induced apoptosis, Ca²⁺ influx and mitochondrial reactive oxygen species (ROS) in several tissues except brain and hippocampus. The purpose of this study is to discover the protective effect of MLT and SELEN on DOCE-induced brain and hippocampus oxidative toxicity in mice. MLT and SELEN pretreatments significantly ameliorated acute DOCE-induced mitochondrial ROS production in the hippocampus and brain tissues by reducing levels of lipid peroxidation, intracellular ROS production and mitochondrial membrane depolarization, while increasing levels of total antioxidant status, glutathione, glutathione peroxidase, MLT, α-tocopherol, γ-tocopherol, vitamin A, vitamin C and β-carotene in the tissues. Furthermore, MLT and SELEN pretreatments increased cell viability and TRPM2 channel activation in the hippocampus and brain followed by decreased activations of TNF-α, IL-1β, IL-6, and caspase -3 and - 9, suggesting a suppression of calcium ion influx, apoptosis and inflammation responses. However, modulator role of SELEN on the values in the tissues is more significant than in the MLT treatment. MLT and SELEN prevent DOCE-induced hippocampus and brain injury by inhibiting mitochondrial ROS and cellular apoptosis through regulating caspase -3 and - 9 activation signaling pathways. MLT and SELEN may serve as potential therapeutic targets against DOCE-induced toxicity in the hippocampus and brain.

A Novel Phytochemical, DIM, Inhibits Proliferation, Migration, Invasion and TNF-α Induced Inflammatory Cytokine Production of Synovial Fibroblasts From Rheumatoid Arthritis Patients by Targeting MAPK and AKT/mTOR Signal Pathway

In rheumatoid arthritis(RA) pathogenesis, activated RA fibroblast-like synoviocytes (RA-FLSs) exhibit similar proliferative features as tumor cells and subsequent erosion to cartilage will eventually lead to joint destruction. Therefore, it is imperative to search for compounds, which can effectively inhibit the abnormal activation of RA-FLSs, and retard RA progression.3′3-Diindolylmethane (DIM), the major product of the acid-catalyzed oligomerization of indole-3-carbinol from cruciferous vegetables, has been reported to be functionally relevant to inhibition of migration, invasion and carcinogenesis in some solid tumors. In this study, we explored the anti-proliferation, anti-metastasis and anti-inflammation effects of DIM on RA-FLSs as well as the underlying molecular mechanisms. To do this, primary RA-FLSs were isolated from RA patients and an animal model. Cell proliferation, migration and invasion were measured using CCK-8, scratch, and Transwell assays, respectively. The effects of DIM on Matrix metalloproteinases (MMPs) and some inflammatory factors mRNA and key molecules such as some inflammatory factors and those involved in aberrantly-activated signaling pathway in response to tumor necrosis factor α(TNF-α), a typical characteristic mediator in RA-FLS, were quantitatively measured by real-time PCR and western blotting. Moreover, the effect of DIM on adjuvant induced arthritis(AIA) models was evaluated with C57BL/6 mice in vivo. The results showed that DIM inhibited proliferation, migration and invasion of RA-FLS in vitro. Meanwhile, DIM dramatically suppressed TNF-α–induced increases in the mRNA levels of MMP-2, MMP-3, MMP-8, and MMP-9; as well as the proinflammatory factors IL-6, IL-8, and IL-1β. Mechanistic studies revealed that DIM is able to suppress phosphorylated activation not only of p38, JNK in MAPK pathway but of AKT, mTOR and downstream molecules in the AKT/mTOR pathway. Moreover, DIM treatment decreased expression levels of proinflammatory cytokines in the serum and alleviated arthritis severity in the knee joints of AIA mice. Taken together, our findings demonstrate that DIM could inhibit proliferation, migration and invasion of RA-FLSs and reduce proinflammatory factors induced by TNF-α in vitro by blocking MAPK and AKT/mTOR pathway and prevent inflammation and knee joint destruction in vivo, which suggests that DIM might have therapeutic potential for RA.