The activity against Ehrlich's ascites tumors of doxorubicin contained in self assembled, cell receptor targeted nanoparticle with simultaneous oral delivery of the green tea polyphenol epigallocatechin-3-gallate

Current advances in nanoformulations of therapeutic agents targeting tumor microenvironment to overcome drug resistance

The tumor microenvironment (TME) plays a pivotal role in cancer development and progression. In this line, revealing the precise mechanisms of the TME and associated signaling pathways of tumor resistance could pave the road for cancer prevention and efficient treatment. The use of nanomedicine could be a step forward in overcoming the barriers in tumor-targeted therapy. Novel delivery systems benefit from enhanced permeability and retention effect, decreasing tumor resistance, reducing tumor hypoxia, and targeting tumor-associated factors, including immune cells, endothelial cells, and fibroblasts. Emerging evidence also indicates the engagement of multiple dysregulated mediators in the TME, such as matrix metalloproteinase, vascular endothelial growth factor, cytokines/chemokines, Wnt/β-catenin, Notch, Hedgehog, and related inflammatory and apoptotic pathways. Hence, investigating novel multitargeted agents using a novel delivery system could be a promising strategy for regulating TME and drug resistance. In recent years, small molecules from natural sources have shown favorable anticancer responses by targeting TME components. Nanoformulations of natural compounds are promising therapeutic agents in simultaneously targeting multiple dysregulated factors and mediators of TME, reducing tumor resistance mechanisms, overcoming interstitial fluid pressure and pericyte coverage, and involvement of basement membrane. The novel nanoformulations employ a vascular normalization strategy, stromal/matrix normalization, and stress alleviation mechanisms to exert higher efficacy and lower side effects. Accordingly, the nanoformulations of anticancer monoclonal antibodies and conventional chemotherapeutic agents also improved their efficacy and lessened the pharmacokinetic limitations. Additionally, the coadministration of nanoformulations of natural compounds along with conventional chemotherapeutic agents, monoclonal antibodies, and nanomedicine-based radiotherapy exhibits encouraging results. This critical review evaluates the current body of knowledge in targeting TME components by nanoformulation-based delivery systems of natural small molecules, monoclonal antibodies, conventional chemotherapeutic agents, and combination therapies in both preclinical and clinical settings. Current challenges, pitfalls, limitations, and future perspectives are also discussed.

Self-Assembled Polymers for Gastrointestinal Tract Targeted Delivery through the Oral Route: An Update

Gastrointestinal tract (GIT) targeted drug delivery systems have gained growing attention as potential carriers for the treatment of different diseases, especially local colonic diseases. They have lower side effects as well as enhanced oral delivery efficiency because of various therapeutics that are vulnerable to acidic and enzymatic degradation in the upper GIT are protected. The novel and unique design of self-assembled nanostructures, such as micelles, hydrogels, and liposomes, which can both respond to external stimuli and be further modified, making them ideal for specific, targeted medical needs and localized drug delivery treatments through the oral route. Therefore, the aim of this review was to summarize and critically discuss the pharmaceutical significance and therapeutic feasibility of a wide range of natural and synthetic biomaterials for efficient drug targeting to GIT using the self-assembly method. Among various types of biomaterials, natural and synthetic polymer-based nanostructures have shown promising targeting potential due to their innate pH responsiveness, sustained and controlled release characteristics, and microbial degradation in the GIT that releases the encapsulated drug moieties.

Enhanced anticancer activity of siRNA and drug codelivered by anionic biopolymer: overcoming electrostatic repulsion

Aim: To codeliver an anticancer drug (doxorubicin) and siRNA in the form of nanoparticles into CD44-overexpressing colon cancer cells (HT-29) using an anionic, amphiphilic biopolymer comprising modified hyaluronic acid (6-O-[3-hexadecyloxy-2-hydroxypropyl]-hyaluronic acid). Materials & methods: Characterization of nanoparticles was performed using dynamic light scattering, scanning electron microscopy, transmission electron microscopy, molecular docking, in vitro drug release and gel mobility assays. Detailed in vitro experiments, including a gene silencing study and western blot, were also performed. Results: A 69% knockdown of the target gene was observed, and western blot showed 5.7-fold downregulation of the target protein. The repulsive forces between siRNA and 6-O-(3-hexadecyloxy-2-hydroxypropyl)-hyaluronic acid were overcome by hydrogen bonding and hydrophobic interactions. Conclusion: The authors successfully codelivered a drug and siRNA by anionic vector.

Quatramer™ Mediated Codelivery of PI3-Kδ/HDAC6 Dual Inhibitor Augments the Anti-Cancer Efficacy of Epirubicin in Breast Cancer

The disruption and overexpression of phosphatidylinositol 3-kinase (PI3K)-AKT signaling pathway in cancer results in tumor growth, metastasis, and survival. Treatment with common anthracyclines has confirmed cancer cells' dependence on PI3K pathway through overexpression of AKT. Moreover, combining HDAC inhibitor with anthracycline has shown the targeting of breast cancer stem cells. Therefore, it has been hypothesized that the co-delivery of PI3-Kδ/HDAC6 dual inhibitor with Epirubicin using polymeric nanoparticle could increase the anti-cancer treatment efficacy with reduced toxicity. Pluronic modified polylactic acid block copolymer (quatramer) was used for encapsulation of PI3-Kδ/HDAC6 and Epirubicin. The co-encapsulated nanoparticles, PI3-Kδ/HDAC6-Epi-NPs have shown size of 99±3 nm, PDI of 0.18±0.07 with a sustained and slow-release profile in non-physiological buffer (PBS, pH 7.4). The in-vitro cell proliferation inhibition studies done on 2D and 3D culture of breast cancer cell lines have confirmed the synergistic effect of PI3-Kδ/HDAC6-Epi-NPs with lower IC₅₀ values compared to PI3-Kδ/HDAC6-NPs and Epi-NPs. Additionally, intravenous twice a week treatment for three weeks with PI3-Kδ/HDAC6-Epi-NPs resulted in complete tumor eradication in the syngeneic breast tumor mice model. In comparison, the PI3-Kδ/HDAC6-NPs and Epi-NPs result in tumor growth inhibition of 15.86% and 81.59%, respectively. These studies predicted that clinical use of PI3-Kδ/HDAC6-Epi-NPs will be effective in breast cancer treatments.

Emerging trends in nano-bioactive-mediated mitochondria-targeted therapeutic stratagems using polysaccharides, proteins and lipidic carriers

The emergence of new lifestyle disorders and pharmaco-resistant variants of diseases has necessitated the search for effective therapeutic moieties and approaches that could overcome the limitations in the existing treatment modalities. In this context, bioactives such as flavonoids, polyphenols, tannins, terpenoids and alkaloids have demonstrated promise in therapy owing to their ability to scavenge free radicals and modulate the mitochondrial function as well as regulate metabolic pathways. However, their clinical applicability is low owing to their poor bioavailability and aqueous solubility. The encapsulation of bioactives in nanodimensional particles has overcome these limitations to a large extent while simultaneously conferring additional advantages of improved circulation time, enhanced cell uptake and target specific release. A wide range of nanocarriers derived from biopolymers such as polysaccharides, lipids and proteins, have been explored for encapsulation of different bioactives and have reported significant improvement of the bioavailability and therapeutic efficacy of the encapsulated cargo. However, incorporation of cell-specific and mitochondria-specific elements on the nanocarriers has been relatively less explored. This review summarizes some of the recent attempts to treat different disorders using bioactives encapsulated in biopolymer nanostructures and few instances of mitochondria-specific delivery.

Phyto-drug conjugated nanomaterials enhance apoptotic activity in cancer

Cancer continues to be one of the leading causes of death worldwide and is a major obstacle to increased life expectancy. However, survival has not improved significantly with average cancer standard treatment strategies over the past few decades; survival rates have remained low, with tumor metastasis, adverse drug reactions, and drug resistance. Therefore, substitute therapies are essential to treat this dreadful disease. Recently, research has shown that natural compounds in plants, such as phytochemicals, are extensively exploited for their anticarcinogenic potential. Phytochemicals may show their anticancer activity different cancer cell markers may alter molecular pathways, which promote in cellular events such as cell cycle arrest and apoptosis, regulate antioxidant status, cell proliferation, migration, invasion and toxicity. Although their outstanding anticancer activity, however, their pharmacological budding is hindered by their low aqueous solubility, poor bioavailability, and poor penetration into cells, hepatic disposition, narrow therapeutic index, and rapid uptake by normal tissues. In this situation, nanotechnology has developed novel inventions to increase the potential use of phytochemicals in anticancer therapy. Nanoparticles can improve the solubility and stability of phytochemicals, specific tumor cell/tissue targeting, enhanced cellular uptake, reduction of phytochemicals. Therapeutic doses of phytochemicals for a long time. Additional benefits include better blood stability, multifunctional design of nanocarriers and improvement in countermeasures. This review summarizes the advances in the use of nanoparticles for the treatment of cancer, as well as various nano-drug deliveries of phytochemicals against cancer. In particular, we are introducing several applications of nanoparticles in combination with phyto-drug for the treatment of cancer.

Efficient antileishmanial activity of amphotericin B and piperine entrapped in enteric coated guar gum nanoparticles

Amphotericin B (AmB) exhibits potential antileishmanial activity, with only a little rate of recurrence. However, low bioavailability and severe nephrotoxicity are among the major shortcomings of AmB-based therapy. Various AmB nanoformulations have been developed, which to an extent, have reduced its toxicity and increased the drug efficacy. To further reduce the nonspecific tissue distribution and the cost of the treatment, the current AmB-based formulations require additional improvements. Combination of natural bioenhancers with AmB is expected to further increase its bioavailability. Therefore, we developed a nanoformulation of AmB and piperine (Pip), a plant alkaloid, known to enhance the bioavailability of various drugs, by entrapping them in guar gum, a macrophage targeting polymer. Owing to the ease of oral delivery, these nanoparticles (NPs) were coated with eudragit to make them suitable for oral administration. The formulated eudragit-coated AmB and Pip-loaded NPs (Eu-HDGG-AmB-Pip-NPs) exhibited controlled release of the loaded therapeutic agents and protected the drug from acidic pH. These NPs exhibited effective suppression of growth of both promastigotes and amastigotes of Leishmania donovani parasite under in vitro. In vivo evaluation of these NPs for therapeutic efficacy in golden hamster-L. donovani model demonstrated enhanced drug bioavailability, non-nephrotoxic nature, and potential antileishmanial activity with up to 96% inhibition of the parasite. Graphical abstract.

Potential of nano-phytochemicals in cervical cancer therapy

Cervical cancer is common among women with a recurrence rate of 35% despite surgery, radiation, and chemotherapy. Patients receiving chemotherapy or radiotherapy routinely experience several side effects including toxicity, non-targeted damage of tissues, hair loss, neurotoxicity, multidrug resistance (MDR), nausea, anemia and neutropenia. Phytochemicals can interfere with almost every stage of carcinogenesis to prevent cancer development. Many natural compounds are known to activate/deactivate multiple redox-sensitive transcription factors that modulate tumor signaling pathways. Polyphenols have been found to be promising agents against cervical cancer. However, applications of phytochemicals as a therapeutic drug are limited due to low oral bioavailability, poor aqueous solubility and requirement of high doses. Nano-sized phytochemicals (NPCs) are promising anti-cancer agents as they are required in minute quantities which lowers overall treatment costs. Several phytochemicals, including quercetin, lycopene, leutin, curcumin, green tea polyphenols and others have been packaged as nanoparticles and proven to be useful in nano-chemoprevention and nano-chemotherapy. Nanoparticles have high biocompatibility, biodegradability and stability in biological environment. Nano-scale drug delivery systems are excellent source for enhanced drug specificity, improved absorption rates, reduced drug degradation and systemic toxicity. The present review discusses current knowledge in the involvement of phytochemical nanoparticles in cervical cancer therapy over conventional chemotherapy.

Dietary flavonoids: Nano delivery and nanoparticles for cancer therapy

Application of nanotechnologies to cancer therapy might increase solubility and/or bioavailability of bioactive compounds of natural or synthetic origin and offers other potential benefits in cancer therapy, including selective targeting. In the present review we aim to evaluate in vivo studies on the anticancer activity of nanoparticles (NPs) obtained from food-derived flavonoids. From a systematic search a total of 60 studies were identified. Most of the studies involved the flavanol epigallocatechin-3-O-gallate and the flavonol quercetin, in both delivery and co-delivery (with anti-cancer drugs) systems. Moreover, some studies investigated the effects of other flavonoids, such as anthocyanins aglycones anthocyanidins, flavanones, flavones and isoflavonoids. NPs inhibited tumor growth in both xenograft and chemical-induced animal models of cancerogenesis. Encapsulation improved bioavailability and/or reduced toxicity of both flavonoids and/or co-delivered drugs, such as doxorubicin, docetaxel, paclitaxel, honokiol and vincristine. Moreover, flavonoids have been successfully applied in molecular targeted nanosystems. Selectivity for cancer cells involves pH- and/or reactive oxygen species-mediated mechanisms. Furthermore, flavonoids are good candidates as drug delivery for anticancer drugs in green synthesis systems. In conclusion, although human studies are needed, NPs obtained from food-derived flavonoids have promising anticancer effects in vivo.

Anti-Cancerous Potential of Polyphenol-Loaded Polymeric Nanotherapeutics

Recent evidence has extensively demonstrated the anticancer potential of nutraceuticals, including plant polyphenols. Polymeric nanocarrier systems have played an important role in improving the physicochemical and pharmacological properties of polyphenols, thus ameliorating their therapeutic effectiveness. This article summarizes the benefits and shortcomings of various polymeric systems developed for the delivery of polyphenols in cancer therapy and reveals some ideas for future work.

Preparation and characterization of layer-by-layer hypoglycemic nanoparticles with pH-sensitivity for oral insulin delivery

We developed an insulin oral delivery system with the combination of pH-sensitive material and structure to avoid intestinal degradation.

Inhibition of Thioredoxin Reductase by Targeted Selenopolymeric Nanocarriers Synergizes the Therapeutic Efficacy of Doxorubicin in MCF7 Human Breast Cancer Cells

Increasing evidence suggests selenium nanoparticles (Se NPs) as potential cancer therapeutic agents and emerging drug delivery carriers, yet, the molecular mechanism of their anticancer activity still remains unclear. Recent studies indicate thioredoxin reductase (TrxR), a selenoenzyme, as a promising target for anticancer therapy. The present study explored the TrxR inhibition efficacy of Se NPs as a plausible factor impeding tumor growth. Hyaluronic acid (HA)-functionalized selenopolymeric nanocarriers (Se@CMHA NPs) were designed wielding chemotherapeutic potential for target specific Doxorubicin (DOX) delivery. Se@CMHA nanocarriers are thoroughly characterized asserting their chemical and physical integrity and possess prolonged stability. DOX-loaded selenopolymeric nanocarriers (Se@CMHA-DOX NPs) exhibited enhanced cytotoxic potential toward human cancer cells compared to free DOX in an equivalent concentration eliciting its selectivity. In first-of-its-kind findings, selenium as Se NPs in these polymeric carriers progressively inhibit TrxR activity, further augmenting the anticancer efficacy of DOX through a synergistic interplay between DOX and Se NPs. Detailed molecular studies on MCF7 cells also established that upon exposure to Se@CMHA-DOX NPs, MCF7 cells endure G2/M cell cycle arrest and p53-mediated caspase-independent apoptosis. To gauge the relevance of the developed nanosystem in in vivo settings, three-dimensional tumor sphere model mimicking the overall tumor environment was also performed, and the results clearly depict the effectiveness of our nanocarriers in reducing tumor activity. These findings are reminiscent of the fact that our Se@CMHA-DOX NPs could be a viable modality for effective cancer chemotherapy.

pH-Responsive Nanoscale Coordination Polymer for Efficient Drug Delivery and Real-Time Release Monitoring

Both excess dosages of drug and unwanted drug carrier can lead to severe side effects as well as the failure of tumor therapy. Here, an Fe³⁺ -gallic acid based drug delivery system is designed for efficient monitoring of drug release in tumor. Fe³⁺ and polyphenol gallic acid can form polygonal nanoscale coordination polymer in aqueous solution, which exhibits certain antitumor effect. Importantly, this coordination polymer possesses extremely high doxorubicin (DOX) loading efficacy (up to 48.3%). In vitro studies demonstrate that the fluorescence of DOX can be quenched efficiently when DOX is loaded on the coordination polymer. The acidity in lysosome also triggers the release of DOX and fluorescence recovery simultaneously, which realizes real-time monitoring of drug release in tumor cells. In vivo studies further indicate that this polyphenol-rich drug delivery system can significantly inhibit tumor growth with negligible heart toxicity of DOX. This system with minimal side effects should be a promising nanoplatform for tumor treatment.

Curcumin loading potentiates the chemotherapeutic efficacy of selenium nanoparticles in HCT116 cells and Ehrlich's ascites carcinoma bearing mice

The anticancer properties of selenium (Se) and curcumin nanoparticles in solo formulations as well as in combination with other therapeutic agents have been proved time and again. Exploiting this facet of the two, we clubbed their tumoricidal characteristics and designed curcumin loaded Se nanoparticles (Se-CurNPs) to achieve an enhanced therapeutic effect. We evaluated their therapeutic effects on different cancer cell lines and Ehrlich's ascites carcinoma mouse model. In vitro results showed that Se-CurNPs were most effective on colorectal carcinoma cells (HCT116) compared to the other cancer cell lines used and possessed pleiotropic anticancer effects. The therapeutic effect on HCT116 was primarily attributed to an elevated level of autophagy and apoptosis as evident from significant up-regulation of autophagy associated (LC3B-II) and pro-apoptotic (Bax) proteins, down-regulation of anti-apoptotic (Bcl-2) protein and Cytochrome c (cyt c) release from mitochondria along with reduced NFκB signaling and EMT based machineries marked by downregulation of inflammation (NFκB, phospho-NFκB) and epithelial-mesenchymal transition (CD44, N-cadherin) associated proteins. In vivo studies on Ehrlich's ascites carcinoma (EAC) mice model indicated that Se-CurNPs significantly reduced the tumor load and enhanced the mean survival time (days) of tumor-bearing EAC mice.

Evaluation of growth inhibitory response of Resveratrol and Salinomycin combinations against triple negative breast cancer cells

Resveratrol (RSVL) a dietary phytochemical showed to enhance the efficacy of chemotherapeutic drugs. Recently, Salinomycin (SAL) has gained importance as cancer therapeutic value for breast cancer (BC), however, its superfluxious toxicity delimits the utility. Taking the advantage of RSVL, the therapeutic efficacy of RSVL and SAL combination was studied in vitro and in vivo system. Firstly, the synergistic combination dose of RSVL and SAL was calculated and further, the efficacy was examined by wound healing, and Western blots analysis. Further, in vivo study was performed to confirm the effect of colony formation and apoptosis detection by flow cytometry based assays. Further, the molecular mode of action was determined at both transcript and translational level by quantitative Real Time PCR combination in Ehrlich ascitic carcinoma model.The combination of IC20 (R20) of RSVL and IC10 (S10) dose of SAL showed best synergism (CI<1) with ∼5 fold dose advantage of SAL. Gene expression results at mRNA and protein level revealed that the unique combination of RSVL and SAL significantly inhibited epithelial mesenchymal transition (Fibronectin, Vimentin, N-Cadherin, and Slug); chronic inflammation (Cox2, NF-kB, p53), autophagy (Beclin and LC3) and apoptotic (Bax, Bcl-2) markers. Further, i n vivo study showed that low dose of SAL in combination with RSVL increased life span of Ehrlich ascitic mice. Overall, our study revealed that RSVL synergistically potentiated the anticancer potential of SAL against triple negative BC.

Synergism of co-delivered nanosized antioxidants displayed enhanced anticancer efficacy in human colon cancer cell lines

Combination of chemopreventive and/or therapeutic agents is the imminent smart approach to cope up with cancer because it may act on multiple targets through different pathways. In the present study, we have synthesized multiple chemopreventive and/or therapeutic agents (Curcumin, Quercetin and Aspirin) loaded nanoparticles by simple cation-anion interaction among the amine groups of chitosan (CS) and phosphate groups of sodium hexametaphosphate (SHMP). These nanosized bioactive materials (CS-SHMP-CQA-NPs) were well characterized and found most effective in colon cancer cell line (HCT-116) compared to other cancer cell lines. Triplex chemopreventive and/or therapeutic agents-loaded NPs were synergistically inducing apoptosis in HCT-116 cells compared to two-chemopreventive agents-loaded NPs as evident by an increase in sub-G₁ cells (percent), and chromatin condensation along with the decrease in mitochondrial membrane potential (MMP). Interestingly, Chou–Talalay analysis revealed that CS-SHMP-CQA-NPs showed strong synergistic effect in its all doses. Thus, our study demonstrates that nanoparticles based bioactive materials significantly inhibit the growth of HCT-116 cells and thus could be a promising approach for colon cancer chemoprevention.

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Multiple antioxidants loaded nanoparticle base bioactive materials have been synthesized.

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This nanoparticular bioactive materials (CS-SHMP-CQA-NPs) were well characterized and found most effective in colon cancer cell line (HCT-116) compared to other cancer cell lines.

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Nanosized bioactivematerial inhibited HCT-116 cells synergistically, could be a promising approach for colon cancer chemotherapy.

Polyphenols delivery by polymeric materials: challenges in cancer treatment

Nanotechnology can offer different solutions for enhancing the therapeutic efficiency of polyphenols, a class of natural products widely explored for a potential applicability for the treatment of different diseases including cancer. While possessing interesting anticancer properties, polyphenols suffer from low stability and unfavorable pharmacokinetics, and thus suitable carriers are required when planning a therapeutic protocol. In the present review, an overview of the different strategies based on polymeric materials is presented, with the aim to highlight the strengths and the weaknesses of each approach and offer a platform of ideas for researchers working in the field.

Recent advances in complementary and replacement therapy with nutraceuticals in combating gastrointestinal illnesses

The digestive system provides nourishment to the whole body. Disorders in this system would result in many associated illnesses as the body is deprived of essential nutrients. Gastrointestinal diseases, in particular, gastric ulceration, inflammatory bowel diseases and colorectal cancer have become more prevalent in all population age groups. While this can be attributed to diet and lifestyle changes, the measures to combat these illnesses with conventional drugs is losing popularity owing to the harsh side effects, drug resistance and lack of patient compliance. The focus of this review is to endorse promising nutraceutical dietary components such as phytosterols, polyphenols, anthocyanins and polyunsaturated fatty acids and their synergistic value, in combination with conventional management of key gastrointestinal diseases. As most of these nutraceuticals are labile compounds, the need for protection and delivery using a carrier system is stressed and the methods for targeting to specific parts of the gastrointestinal tract are discussed. A section has also been devoted to perspectives on co-encapsulation methods of drugs and nutraceuticals using different particle systems. Multilayered carrier systems like double layered and core shell particles have been proposed as an exemplary system to co-encapsulate both drugs and nutrients while keeping them segregated.

Hyaluronic acid grafted PLGA copolymer nanoparticles enhance the targeted delivery of Bromelain in Ehrlich's Ascites Carcinoma

Rapidly increasing malignant neoplastic disease demands immediate attention. Several dietary compounds have recently emerged as strong anti-cancerous agents. Among, Bromelain (BL), a protease from pineapple plant, was used to enhance its anti-cancerous efficacy using nanotechnology. In lieu of this, hyaluronic acid (HA) grafted PLGA copolymer, having tumor targeting ability, was developed. BL was encapsulated in copolymer to obtain BL-copolymer nanoparticles (NPs) that ranged between 140 to 281nm in size. NPs exhibited higher cellular uptake and cytotoxicity in cells with high CD44 expression as compared with non-targeted NPs. In vivo results on tumor bearing mice showed that NPs were efficient in suppressing the tumor growth. Hence, the formulation could be used as a self-targeting drug delivery cargo for the remission of cancer.

Resveratrol improves the anticancer effects of doxorubicin in vitro and in vivo models: A mechanistic insight

BACKGROUND

Resveratrol (RSVL), a well known dietary compound and in combination with doxorubicin (DOX) has gained a global importance for cancer prevention. However, mechanism of action by this combination is not well understood till date.

HYPOTHESIS

The synergistic combination of RSVL and DOX might be more effective in anti-cancer activity by modulating the diverse cancer signaling pathways as compared to their alone treatments.

METHODS

The cytotoxicity of alone and combination doses of RSVL and DOX were analyzed by colorimetric MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) cell proliferation assay. The migration and colony forming abilities were evaluated by wound healing and clonogenic assays. Apoptosis was detected by Annexin V/PI and DAPI stainings. The cell cycle and intracellular reactive oxygen species (ROS) generation were measured by flow cytometry. The differential expression of genes and proteins were measured by qRT-PCR and western blotting analyses. Finally, in-vivo studies were performed in Ehrlich ascitic carcinoma (EAC) mouse model.

RESULTS

The synergistic combination of DOX (IC20) and RSVL (IC30) was selected based on the combination index values in MCF-7 and MDA-MB-231 cell lines. This combination showed potent growth inhibition with ∼2.5 fold of dose advantage and also significantly decreased the wound healing and clonogenic potential of breast cancer cells. The combination treatment was also found to inhibit the inflammatory response (NF-kB, COX-2), autophagic flux (LC3, Beclin-1), redox regulation (Nrf2) and induces apoptosis (BAX: BCL-2 ratio and Caspase-9) in breast cancer cells. Further, combined dosages of DOX (5 mg/kg b.wt) and RSVL (10 mg/kg b.wt) inhibited tumor volume with increased life span (139%, p value<0.05) in Ehrlich ascitic carcinoma (EAC) cells bearing mice.

CONCLUSION

In brief, our results suggested that resveratrol chemosensitizes doxorubicin in combination, through inhibiting breast cancer cells proliferation and invasion, and inducing apoptosis via suppression of chronic inflammation and autophagy.

Green tea polyphenols and their potential role in health and disease

There is a growing body of evidence that plant polyphenols such as resveratrol, anthocyanins, catechins, and terpenes like taxol are effectively used in the treatment of chronic conditions including cancer, Alzheimer, Parkinsonism, diabetes, aging, etc. The link between oxidative stress and inflammation is well accepted. Thus, the mechanism of action of these natural products is partly believed to be through their significant antioxidant properties. The main constituent of green tea, with clinical significance, is epigallocatechin gallate (EGCG). It has been associated with antitumor, anti-Alzheimer, and anti-aging properties, improve redox status at the tissue level possibly preventing system level structural damage. This review focuses on EGCG and its potential therapeutic role in health and disease.

Smart doxorubicin nanoparticles with high drug payload for enhanced chemotherapy against drug resistance and cancer diagnosis

Considering the obvious advantages in efficacy and price, doxorubicin (DOX) has been widely used for a range of cancers, which is usually encapsulated in various nanocarriers for drug delivery. Although effective, in most nanocarrier-based delivery systems, the drug loading capacity of DOX is rather low; this can lead to undesired systemic toxicity and excretion concern. Herein, we report for the first time the usage of pure doxorubicin nanoparticles (DOX NPs) without addition of any carriers for enhanced chemotherapy against drug-resistance. The drug payload reaches as high as 90.47%, which largely surpassed those in previous reports. These PEG stabilized DOX NPs exhibit good biocompatibility and stability, long blood circulation time, fast release in an acidic environment and high accumulation in tumors. Compared with free DOX, DOX NPs display a dramatically enhanced anticancer therapeutic efficacy in the inhibition of cell and tumor growth. Moreover, they can also be readily incorporated with other anticancer drugs for synergistic chemotherapy to overcome the drug resistance of cancers. The fluorescence properties of DOX also endow these NPs with imaging capabilities, thus making it a multifunctional system for diagnosis and treatment. This work demonstrates great potential of DOX NPs for cancer diagnosis, therapy and overcoming drug tolerance.

Carbohydrate nanocarriers in biomedical applications: functionalization and construction

Carbohydrates are used to functionalize or construct nanocarriers for biomedical applications – specific targeting, biocompatibility, stealth effect, biodegradability.

Design and synthesis of N-acylated aza-goniothalamin derivatives and evaluation of their in vitro and in vivo antitumor activity

Herein we describe the synthesis of a focused library of compounds based on the structure of goniothalamin (1) and the evaluation of the potential antitumor activity of the compounds. N-Acylation of aza-goniothalamin (2) restored the in vitro antiproliferative activity of this family of compounds. 1-(E)-But-2-enoyl-6-styryl-5,6-dihydropyridin-2(1H)-one (18) displayed enhanced antiproliferative activity. Both goniothalamin (1) and derivative 18 led to reactive oxygen species generation in PC-3 cells, which was probably a signal for caspase-dependent apoptosis. Treatment with derivative 18 promoted Annexin V/7-aminoactinomycin D double staining, which indicated apoptosis, and also led to G2 /M cell-cycle arrest. In vivo studies in Ehrlich ascitic and solid tumor models confirmed the antitumor activity of goniothalamin (1), without signs of toxicity. However, derivative 18 exhibited an unexpectedly lower in vivo antitumor activity, despite the treatments being administered at the same site of inoculation. Contrary to its in vitro profile, aza-goniothalamin (2) inhibited Ehrlich tumor growth, both on the ascitic and solid forms. Our findings highlight the importance of in vivo studies in the search for new candidates for cancer treatment.

Nanocomplexes based on amphiphilic hyaluronic acid derivative and polyethylene glycol-lipid for ginsenoside rg3 delivery

Hybrid nanocomplex formulations, based on amphiphilic hyaluronic acid-ceramide (HACE) and lipids, were fabricated for the delivery of 20(S)-ginsenoside Rg 3 [(S)-Rg3]. Nanocomplexes with less than 200 nm mean diameter, narrow size distribution, spherical shape, and negative zeta potential were prepared. The maintenance of the structural stability of the hybrid nanocomplexes in the blood stream was demonstrated by measuring their particle size in serum. Nanocomplexes based on HACE, phosphatidylcholine (PC), and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-PEG) showed a sustained drug release profile compared with other formulations. Blank nanocomplexes exhibited negligible cytotoxicity within the tested concentration range in A549 human lung adenocarcinoma cells. The cellular uptake efficiency of hybrid nanocomplexes was improved compared with the HACE-based nanoparticles probably because of interactions between lipids and the cellular membrane. The results of a pharmacokinetic study in rats revealed decreased in vivo clearance of (S)-Rg3, especially in the HACE/PC/DSPE-PEG-based hybrid nanocomplex (F3) group. The hybrid nanostructure and the outer PEG chain likely contributed to improve in vivo performance of the F3 group. Thus, these developed hybrid nanocomplexes could serve as good candidates for tumor-targeted delivery of anticancer agents.

Does tea prevent cancer? Evidence from laboratory and human intervention studies

Tea (Camellia sinensis) is a widely consumed beverage and has been extensively studied for its cancer-preventive activity. Both the polyphenolic constituents as well as the caffeine in tea have been implicated as potential cancer-preventive compounds; the relative importance seems to depend on the cancer type. Green tea and the green tea catechin have been shown to inhibit tumorigenesis at a number of organ sites and to be effective when administered either during the initiation or postinitiation phases of carcinogenesis. Black tea, although not as well studied as green tea, has also shown cancer-preventive effects in laboratory models. A number of potential mechanisms have been proposed to account for the cancer-preventive effects of tea, including modulation of phase II metabolism, alterations in redox environment, inhibition of growth factor signaling, and others. In addition to the laboratory studies, there is a growing body of human intervention studies suggesting that tea can slow cancer progression and modify biomarkers relevant to carcinogenesis. Although available data are promising, many questions remain with regard to the dose-response relations of tea constituents in various models, the primary mechanisms of action, and the potential for combination chemoprevention strategies that involve tea as well as other dietary or pharmaceutical agents. The present review examines the available data from laboratory animal and human intervention studies on tea and cancer prevention. These data were evaluated, and areas for further research are identified.

Treatment with EGCG promotes doxorubicin-induced cell senescence in gastric cancer cell line MKN28

AIM: To investigate the effect of treatment with (-)-epigallocatechin-3-gallate (EGCG) on EZH2 expression and doxorubicin-induced cell senescence in gastric cancer cell line MKN28.

METHODS: MKN28 cells were treated with EGCG in the presence or absence of doxorubicin. Protein expression of EZH2 was detected by Western blot. Doxorubicin-induced senescence of MKN28 cells was analyzed by senescence-associated β-galactosidase (SA-β-gal) staining. The formation of senescence-associated heterochromatic foci (SAHF) was measured by laser confocal microscopy. Cell cycle progression and cell proliferation of treated MKN28 cells were measured by flow cytometry and MTT assay, respectively.

RESULTS: EGCG effectively suppressed the expression of EZH2 protein and promoted doxorubicin-induced cell senescence and formation of SAHF in MKN28 cells. In the EGCG + doxorubicin group, the percentages of cells positive for SA-β-gal and SAHF formation proportion were increased more significantly than those in the doxorubicin group and EGCG group (72.16% ± 4.03% vs 34.42% ± 7.06%, 15.40% ± 1.70%; 86.44% ± 4.33% vs 47.73% ± 3.03%, 80.28% ± 1.24%). In EGCG-treated MKN28 cells, the proportion of cells in G₀/G₁ phase and reduced rate of cell proliferation increased with the increase in the concentration of EGCG, and this effect was more notable in the presence of doxorubicin.

CONCLUSION: EGCG can effectively suppress the expression of EZH2 and therefore promote doxorubicin-induced cell senescence in MKN28 cells.