Design, synthesis, and mechanistic investigations of bile acid-tamoxifen conjugates for breast cancer therapy

Exploiting the bile acid binding protein as transporter of a Cholic Acid/Mirin bioconjugate for potential applications in liver cancer therapy

Bioconjugation is one of the most promising strategies to improve drug delivery, especially in cancer therapy. Biomolecules such as bile acids (BAs) have been intensively explored as carriers, due to their peculiar physicochemical properties and biocompatibility. BAs trafficking is regulated by intracellular lipid-binding proteins and their transport in the liver can be studied using chicken liver Bile Acid-Binding Proteins (cL-BABPs) as a reference model. Therefore, we conceived the idea of developing a BA-conjugate with Mirin, an exonuclease inhibitor of Mre11 endowed with different anticancer activities, to direct its transport to the liver. Following computational analysis of various BAs in complex with cL-BABP, we identified cholic acid (CA) as the most promising candidate as carrier, leading to the synthesis of a novel bioconjugate named CA-M11. As predicted by computational data and confirmed by X-ray crystallographic studies, CA-M11 was able to accommodate into the binding pocket of BABP. Hence, it can enter BAs trafficking in the hepatic compartment and here release Mirin. The effect of CA-M11, evaluated in combination with varying concentrations of Doxorubicin on HepG2 cell line, demonstrated a significant increase in cell mortality compared to the use of the cytotoxic drug or Mirin alone, thus highlighting chemo-sensitizing properties. The promising results regarding plasma stability for CA-M11 validate its potential as a valuable agent or adjuvant for hepatic cancer therapy.

Mitochondrial metabolism blockade nanoadjuvant reversed immune-resistance microenvironment to sensitize albumin-bound paclitaxel-based chemo-immunotherapy

Currently, the efficacy of albumin-bound paclitaxel (PTX@Alb) is still limited due to the impaired PTX@Alb accumulation in tumors partly mediated by the dense collagen distribution. Meanwhile, acquired immune resistance always occurs due to the enhanced programmed cell death-ligand 1 (PD-L1) expression after PTX@Alb treatment, which then leads to immune tolerance. To fill these gaps, we newly revealed that tamoxifen (TAM), a clinically widely used adjuvant therapy for breast cancer with mitochondrial metabolism blockade capacity, could also be used as a novel effective PD-L1 and TGF-β dual-inhibitor via inducing the phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) protein. Following this, to obtain a more significant effect, TPP-TAM was prepared by conjugating mitochondria-targeted triphenylphosphine (TPP) with TAM, which then further self-assembled with albumin (Alb) to form TPP-TAM@Alb nanoparticles. By doing this, TPP-TAM@Alb nanoparticles effectively decreased the expression of collagen in vitro, which then led to the enhanced accumulation of PTX@Alb in 4T1 tumors. Besides, TPP-TAM@Alb also effectively decreased the expression of PD-L1 and TGF-β in tumors to better sensitize PTX@Alb-mediated chemo-immunotherapy by enhancing T cell infiltration. All in all, we newly put forward a novel mitochondrial metabolism blockade strategy to inhibit PTX@Alb-resistant tumors, further supporting its better clinical application.

The anticancer activity of bile acids in drug discovery and development

Bile acids (BAs) constitute essential components of cholesterol metabolites that are synthesized in the liver, stored in the gallbladder, and excreted into the intestine through the biliary system. They play a crucial role in nutrient absorption, lipid and glucose regulation, and the maintenance of metabolic homeostasis. In additional, BAs have demonstrated the ability to attenuate disease progression such as diabetes, metabolic disorders, heart disease, and respiratory ailments. Intriguingly, recent research has offered exciting evidence to unveil their potential antitumor properties against various cancer cell types including tamoxifen-resistant breast cancer, oral squamous cell carcinoma, cholangiocarcinoma, gastric cancer, colon cancer, hepatocellular carcinoma, prostate cancer, gallbladder cancer, neuroblastoma, and others. Up to date, multiple laboratories have synthesized novel BA derivatives to develop potential drug candidates. These derivatives have exhibited the capacity to induce cell death in individual cancer cell types and display promising anti-tumor activities. This review extensively elucidates the anticancer activity of natural BAs and synthetic derivatives in cancer cells, their associated signaling pathways, and therapeutic strategies. Understanding of BAs and their derivatives activities and action mechanisms will evidently assist anticancer drug discovery and devise novel treatment.

Gut Metabolite Indoxyl Sulfate Has Selective Deleterious and Anticancer Effect on Colon Cancer Cells

There are a number of reports about anticancer activity of indole derivatives. In this study, we investigated the role of indoxyl sulfate (IS) for its selective anticancer activity on colon cancer cells. IS treatment on HCT-116 and HT-29 human epithelial adenocarcinoma cells led to a decrease in cell proliferation, cell viability, and ATP content. Colon cancer cells showed a 10% increase in cell apoptosis in comparison to control. Due to IS treatment, cell morphology got distorted, cell number found decreased, intracellular vesicles formed, and cells were found floating in the media. Cells also showed a loss in membrane integrity and a decrease in colony-forming ability and ceased at the G2/M phase of the cell cycle. No significant change was noted in the level of inflammatory cytokines IL-17A, IL-1β, and TNF-α, histology, length of intestine, and spleen after 100 mM IS treatment to balb/c mice. These observations indicate the selective anticancer effect of IS on colon cancer cells.

Anticancer Activity and Molecular Mechanisms of an Ursodeoxycholic Acid Methyl Ester-Dihydroartemisinin Hybrid via a Triazole Linkage in Hepatocellular Carcinoma Cells

Hepatocellular carcinoma is the third most common cause of cancer-related death according to the International Agency for Research on Cancer. Dihydroartemisinin (DHA), an antimalarial drug, has been reported to exhibit anticancer activity but with a short half-life. We synthesized a series of bile acid-dihydroartemisinin hybrids to improve its stability and anticancer activity and demonstrated that an ursodeoxycholic-DHA (UDC-DHA) hybrid was 10-fold more potent than DHA against HepG2 hepatocellular carcinoma cells. The objectives of this study were to evaluate the anticancer activity and investigate the molecular mechanisms of UDCMe-Z-DHA, a hybrid of ursodeoxycholic acid methyl ester and DHA via a triazole linkage. We found that UDCMe-Z-DHA was even more potent than UDC-DHA in HepG2 cells with IC₅₀ of 1 μM. Time course experiments and stability in medium determined by cell viability assay as well as HPLC-MS/MS analysis revealed that UDCMe-Z-DHA was more stable than DHA, which in part accounted for the increased anticancer activity. Mechanistic studies revealed that UDCMe-Z-DHA caused G0/G1 arrest and induced reactive oxygen species (ROS), mitochondrial membrane potential loss and autophagy, which may in turn lead to apoptosis. Compared to DHA, UDCMe-Z-DHA displayed much lower cytotoxicity toward normal cells. Thus, UDCMe-Z-DHA may be a potential drug candidate for hepatocellular carcinoma.

A "Trojan Horse" Strategy: The Preparation of Bile Acid-Modifying Irinotecan Hydrochloride Nanoliposomes for Liver-Targeted Anticancer Drug Delivery System Study

The bile acid transport system is a natural physiological cycling process between the liver and the small intestine, occurring approximately 6-15 times during the day. There are various bile acid transporter proteins on hepatocytes that specifically recognize bile acids for transport. Therefore, in this paper, a novel liposome, cholic acid-modified irinotecan hydrochloride liposomes (named CA-CPT-11-Lip), was prepared based on the "Trojan horse" strategy. The liposomes preparation process was optimized, and some important quality indicators were investigated. The distribution of irinotecan hydrochloride in mice was then analyzed by high-performance liquid chromatography (HPLC), and the toxicity of liposomes to hepatocellular carcinoma cells (HepG-2) was evaluated in vitro. As a result, CA-CPT-11-Lip was successfully prepared. It was spherical with a particle size of 154.16 ± 4.92 nm, and the drug loading and encapsulation efficiency were 3.72 ± 0.04% and 82.04 ± 1.38%, respectively. Compared with the conventional liposomes (without cholic acid modification, named CPT-11-Lip), CA-CPT-11-Lip had a smaller particle size and higher encapsulation efficiency, and the drug accumulation in the liver was more efficient, enhancing the anti-hepatocellular carcinoma activity of irinotecan hydrochloride. The novel nanoliposome modified by cholic acid may help to expand the application of irinotecan hydrochloride in the treatment of hepatocellular carcinoma and construct the drug delivery system mode of drug liver targeting.

Mechanism of Bile Acid-Induced Programmed Cell Death and Drug Discovery against Cancer: A Review

Bile acids are major signaling molecules that play a significant role as emulsifiers in the digestion and absorption of dietary lipids. Bile acids are amphiphilic molecules produced by the reaction of enzymes with cholesterol as a substrate, and they are the primary metabolites of cholesterol in the body. Bile acids were initially considered as tumor promoters, but many studies have deemed them to be tumor suppressors. The tumor-suppressive effect of bile acids is associated with programmed cell death. Moreover, based on this fact, several synthetic bile acid derivatives have also been used to induce programmed cell death in several types of human cancers. This review comprehensively summarizes the literature related to bile acid-induced programmed cell death, such as apoptosis, autophagy, and necroptosis, and the status of drug development using synthetic bile acid derivatives against human cancers. We hope that this review will provide a reference for the future research and development of drugs against cancer.

Naringenin in Si-Ni-San formula inhibits chronic psychological stress-induced breast cancer growth and metastasis by modulating estrogen metabolism through FXR/EST pathway

INTRODUCTION

Chronic psychological stress is a well-established risk factor for breast cancer development. Si-Ni-San (SNS) is a classical traditional Chinese medicine formula prescribed to psychological disorder patients. However, its action effects, molecular mechanisms, and bioactive phytochemicals against breast cancer are not yet clear.

OBJECTIVES

This study aimed to explore the modulatory mechanism and bioactive compound of SNS in regulating estrogen metabolism during breast cancer development induced by chronic psychological stress.

METHODS

Mouse breast cancer xenograft was used to determine the effect of SNS on breast cancer growth and metastasis. Metabolomics analysis was conducted to discover the impact of SNS on metabolic profile changes in vivo. Multiple molecular biology experiments and breast cancer xenografts were applied to verify the anti-metastatic potentials of the screened bioactive compound.

RESULTS

SNS remarkably inhibited chronic psychological stress-induced breast cancer growth and metastasis in the mouse breast cancer xenograft. Meanwhile, chronic psychological stress increased the level of cholic acid, accompanied by the elevation of estradiol. Mechanistic investigation demonstrated that cholic acid activated farnesoid X receptor (FXR) expression, which inhibited hepatocyte nuclear factor 4α (HNF4α)-mediated estrogen sulfotransferase (EST) transcription in hepatocytes, and finally resulting in estradiol elevation. Notably, SNS inhibited breast cancer growth by suppressing estradiol level via modulating FXR/EST signaling. Furthermore, luciferase-reporting gene assay screened naringenin as the most bioactive compound in SNS for triggering EST activity in hepatocytes. Interestingly, pharmacokinetic study revealed that naringenin had the highest absorption in the liver tissue. Following in vivo and in vitro studies demonstrated that naringenin inhibited stress-induced breast cancer growth and metastasis by promoting estradiol metabolism via FXR/EST signaling.

CONCLUSION

This study not only highlights FXR/EST signaling as a crucial target in mediating stress-induced breast cancer development, but also provides naringenin as a potential candidate for breast cancer endocrine therapy via promoting estradiol metabolism.

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

A new chemical library based on the hybridization of cholic acid with the heterocyclic moiety 1,3,4-oxadizole was synthesized, and tested for antimicrobial activity against Gram-positive, Gram-negative bacteria, and fungi. Among the synthesized compounds, the most potent derivatives against S. aureus were 4t, 4i, 4p, and 4c with MIC values between 31 and 70 µg/mL, while compound 4p was the most active one against Bacillus subtilis with a MIC value of 70 µg/mL. Interestingly, compounds 4a and 4u exerted selective activity against Gram-positive bacteria. The synthesized compounds showed good activity against A. fumigatus and C. albicans and compound 4v exhibited selective activity against fungi only.

Engineering of small-molecule lipidic prodrugs as novel nanomedicines for enhanced drug delivery

A widely established prodrug strategy can effectively optimize the unappealing properties of therapeutic agents in cancer treatment. Among them, lipidic prodrugs extremely uplift the physicochemical properties, site-specificity, and antitumor activities of therapeutic agents while reducing systemic toxicity. Although great perspectives have been summarized in the progress of prodrug-based nanoplatforms, no attention has been paid to emphasizing the rational design of small-molecule lipidic prodrugs (SLPs). With the aim of outlining the prospect of the SLPs approach, the review will first provide an overview of conjugation strategies that are amenable to SLPs fabrication. Then, the rational design of SLPs in response to the physiological barriers of chemotherapeutic agents is highlighted. Finally, their biomedical applications are also emphasized with special functions, followed by a brief introduction of the promising opportunities and potential challenges of SLPs-based drug delivery systems (DDSs) in clinical application.

Graphical Abstract

The involvement of oncobiosis and bacterial metabolite signaling in metastasis formation in breast cancer

Breast cancer, the most frequent cancer in women, is characterized by pathological changes to the microbiome of breast tissue, the tumor, the gut, and the urinary tract. Changes to the microbiome are determined by the stage, grade, origin (NST/lobular), and receptor status of the tumor. This year is the 50th anniversary of when Hill and colleagues first showed that changes to the gut microbiome can support breast cancer growth, namely that the oncobiome can reactivate excreted estrogens. The currently available human and murine data suggest that oncobiosis is not a cause of breast cancer, but can support its growth. Furthermore, preexisting dysbiosis and the predisposition to cancer are transplantable. The breast's and breast cancer's inherent microbiome and the gut microbiome promote breast cancer growth by reactivating estrogens, rearranging cancer cell metabolism, bringing about a more inflammatory microenvironment, and reducing the number of tumor-infiltrating lymphocytes. Furthermore, the gut microbiome can produce cytostatic metabolites, the production of which decreases or blunts breast cancer. The role of oncobiosis in the urinary tract is largely uncharted. Oncobiosis in breast cancer supports invasion, metastasis, and recurrence by supporting cellular movement, epithelial-to-mesenchymal transition, cancer stem cell function, and diapedesis. Finally, the oncobiome can modify the pharmacokinetics of chemotherapeutic drugs. The microbiome provides novel leverage on breast cancer that should be exploited for better management of the disease.

Research progress in the application of bile acid-drug conjugates: A "trojan horse" strategy

Bile acid transporters are highly expressed in intestinal cells and hepatocytes, and they determine the uptake of drugs in cells by modulating cellular entry and exit. In order to improve the oral bioavailability of drugs and investigate the potential application prospects of drugs used to target cancer, numerous studies have adopted these transporters to identify prodrug strategies. Through the connection of covalent bonds between drugs and bile acids, the resulting bile acid-drug conjugates continue to be recognized as similar to natural unmodified bile acid and is translocated by the transporter. The present mini-review provides a brief summary of recent progress of the application of bile acid-drug conjugates based primarily on ASBT, NTCP, and OATP, with the hope of contributing to subsequent research.

Bile Acid Conjugates with Anticancer Activity: Most Recent Research

The advantages of a treatment modality that combines two or more therapeutic agents in cancer therapy encourages the study of hybrid functional compounds for pharmacological applications. In light of this, we reviewed recent works on hybrid molecules based on bile acids. Due to their biological properties, as well as their different chemical/biochemical reactive moieties, bile acids can be considered very interesting starting molecules for conjugation with natural or synthetic bioactive molecules.

Promising applications of steroid сonjugates for cancer research and treatment

The conjugation of biologically active molecules is a powerful tool for drug discovery used to target a variety of multifunctional diseases including cancer. Conjugated drugs can provide combination therapies in a single multi-functional agent and, by doing so, be more specific and powerful than conventional classic treatments. Steroids are widely used for conjugation with other biological active molecules. This review refers to investigations of steroid conjugates as potential anticancer agents carried out mostly over the past decade. It consists of five parts in which the data concerning structure and anticancer activity of steroid conjugates with DNA alkylating agents, metallocomplexes, approved drugs, some biological active molecules, some natural compounds and related synthetic analogs are described.

Indoxylsulfate, a Metabolite of the Microbiome, Has Cytostatic Effects in Breast Cancer via Activation of AHR and PXR Receptors and Induction of Oxidative Stress

Changes to bacterial metabolite-elicited signaling, in oncobiosis associated with breast cancer, plays a role in facilitating the progression of the disease. We show that indoxyl-sulfate (IS), a tryptophan metabolite, has cytostatic properties in models of breast cancer. IS supplementation, in concentrations corresponding to the human serum reference range, suppressed tumor infiltration to the surrounding tissues and metastasis formation in a murine model of breast cancer. In cellular models, IS suppressed NRF2 and induced iNOS, leading to induction of oxidative and nitrosative stress, and, consequently, reduction of cell proliferation; enhanced oxidative and nitrosative stress are crucial in the subsequent cytostasis. IS also suppressed epithelial-to-mesenchymal transition vital for suppressing cellular movement and diapedesis. Furthermore, IS rendered cells hypometabolic, leading to a reduction in aldehyde-dehydrogenase positive cells. Pharmacological inhibition of the pregnane-X receptor using CH223191 and the aryl-hydrocarbon receptor using ketoconazole diminished the IS-elicited effects, suggesting that these receptors were the major receptors of IS in these models. Finally, we showed that increased expression of the human enzymes that form IS (Cyp2E1, Sult1A1, and Sult1A2) is associated with better survival in breast cancer, an effect that is lost in triple negative cases. Taken together, IS, similar to indolepropionic acid (another tryptophan metabolite), has cytostatic properties and higher expression of the metabolic machinery responsible for the formation of IS supports survival in breast cancer.

Dihydroartemisinin-Bile Acid Hybridization as an Effective Approach to Enhance Dihydroartemisinin Anticancer Activity

A series of hybrid compounds based on natural products-bile acids and dihydroartemisinin-were prepared by different synthetic methodologies and investigated for their in vitro biological activity against HL-60 leukemia and HepG2 hepatocellular carcinoma cell lines. Most of these hybrids presented significantly improved antiproliferative activities with respect to dihydroartemisinin and the parent bile acid. The two most potent hybrids of the series exhibited a 10.5- and 15.4-fold increase in cytotoxic activity respect to dihydroartemisinin alone in HL-60 and HepG2 cells, respectively. Strong evidence that an ursodeoxycholic acid hybrid induced apoptosis was obtained by flow cytometric analysis and western blot analysis.

Metabolite profiling of traditional Chinese medicine XIAOPI formula: An integrated strategy based on UPLC-Q-Orbitrap MS combined with network pharmacology analysis

XIAOPI formula has been approved for mammary hyperplasia treatment by National Medical Products Administration in China. However, the absorbed substances of XIAOPI formula and their influences on metabolic pathways are largely remained unknown. Liquid chromatography coupled with mass spectrometry was used to identify the substances existing in the serum. Network pharmacology was utilized to explore the underlying metabolic targets and pathways involved in. Western blotting and immunofluorescence assays were carried out for target validation. The exogenous results demonstrated 196 compounds were filtered as absorbed substances, among which 63 constituents or metabolites were tentatively identified in rat serum, and the metabolites of tanshinone II and tanshinone I were found to act as the major metabolic pathways. Subsequently, the endogenous results revealed that XIAOPI formula could significantly regulate serum biochemical indices and the bile acid secretion signaling ranks as top1 among all the involved pathways. The levels of intermediates including cholic acid, glycocholic acid, taurochenodeoxycholic acid and taurocholic acid were significantly upregulated following XIAOPI treatment, accompanied by increased expression of key enzyme CYP7A1, indicating that XIAOPI formula could accelerate the bile acid metabolism pathway. Our study presented a comprehensive metabolic profile of XIAOPI formula in vivo for the first time, and bile acid synthesis pathway might be one of the key mechanisms contributing to the pharmacological function of the formula.

The Apoptosis Effect on Liver Cancer Cells of Gold Nanoparticles Modified with Lithocholic Acid

Functionalized gold nanoparticles (AuNPs) have widely applied in many fields, due to their good biocompatibility, a long drug half-life, and their bioactivity is related to their size and the modified ligands on their surface. Here, we synthesized the AuNPs capped with ligands that possess polyethylene glycol (PEG) and lithocholic acid (LCA) linked by carboxyl groups (AuNP@MPA-PEG-LCA). Our cytotoxicity results indicated that AuNP@MPA-PEG-LCA have better cell selectivity; in other words, it could inhibit the growth of multiple liver cancer cells more effectively than other cancer cells and normal cells. Apoptosis plays a role in AuNP@MPA-PEG-LCA inhibition cell proliferation, which was convincingly proved by some apoptotic index experiments, such as nuclear staining, annexin V-FITC, mitochondrial membrane potential (MMP) analysis, and AO/EB staining experiments. The most potent AuNP@MPA-PEG-LCA were confirmed to efficiently induce apoptosis through a reactive oxygen species (ROS) mediating mitochondrial dysfunction. And AuNP@MPA-PEG-LCA could be more effective in promoting programmed cell death of liver cancer cells.

Drug conjugates-an emerging approach to treat breast cancer

Breast cancer treatment using a single drug is associated with a high failure rate due, in part, to the heterogeneity of drug response within individuals, nonspecific target action, drug toxicity, and/or development of resistance. Use of dual-drug therapies, including drug conjugates, may help overcome some of these roadblocks by more selective targeting of the cancer cell and by acting at multiple drug targets rather than one. Drug-conjugate approaches include linking drugs to antibodies (antibody-drug conjugates), radionuclides (radioimmunoconjugates), nanoparticles (nanoparticle-drug conjugates), or to other drugs (drug-drug conjugates). Although all of these conjugates might be designed as effective treatments against breast cancer, the focus of this review will be on drug-drug conjugates because of the increase in versatility of these types of drugs with respect to mode of action at the level of the cancer cell either by creating a novel pharmacophore or by increasing the potency and/or efficacy of the drugs' effects at their respective molecular targets. The development, synthesis, and pharmacological characteristics of drug-drug conjugates will be discussed in the context of breast cancer with the hope of enhancing drug efficacy and reducing toxicities to improve patient quality of life.

Effective cellular internalization, cell cycle arrest and improved pharmacokinetics of Tamoxifen by cholesterol based lipopolymeric nanoparticles

The present study aims at the development of cholesterol based lipopolymeric nanoparticles for improved entrapment, better cell penetration and improved pharmacokinetics of Tamoxifen (TMX). Self-assembling cholesterol grafted lipopolymer, mPEG-b-(CB-{g-chol}-co-LA) was synthesized from poly(ethyleneglycol)-block-2-methyl-2-carboxyl-propylenecarboxylic acid-co-poly (l-lactide) [mPEG-b-(CB-{g-COOH}-co-LA)] copolymer followed by carbodiimide coupling for attaching cholesterol. Lipopolymeric nanoparticles were prepared using o/w solvent evaporation technique, which were subsequently characterized to determine its particle size, entrapment efficiency, release pattern and compared with mPEG-PLA nanoparticles. Further, in order to assess the in vitro efficacy, cytotoxicity studies, uptake, apoptosis assay and cell cycle analysis were performed in breast cancer cell lines (MCF-7 and 4T1). Finally, the pharmacokinetic profile of TMX loaded mPEG-b-(CB-{g-chol}-co-LA) lipopolymeric nanoparticles was also performed. TMX loaded lipopolymeric nanoparticles of particle size 151.25 ± 3.74 (PDI 0.123) and entrapment efficiency of 73.62 ± 3.08% were formulated. The haemolytic index, protein binding and in vitro drug release of the optimized nanoparticles were found to be comparable to that of the TMX loaded mPEG-PLA nanoparticles. Lipopolymeric nanoparticles demonstrated improved IC₅₀ values in breast cancer cells (22.2 μM in 4T1; 18.8 μM in MCF-7) than free TMX (27.6 μM and 23.5 μM respectively) and higher uptake efficiency. At IC₅₀ values, TMX loaded lipopolymeric nanoparticles induced apoptosis and cell cycle arrest (G₀/G₁ phase) to similar extent as that of free drug. Pharmacokinetic studies indicated ∼2.5-fold increase in the half-life (t_1/2) (p < 0.001) and ∼2.7-fold (p < 0.001) increase in the mean residence time (MRT) of TMX following incorporation into lipopolymeric nanoparticles. Thus, mPEG-b-(CB-{g-chol}-co-LA) lipopolymeric nanoparticles offer a more promising approach for delivery of Tamoxifen in breast cancer by improving drug internalization and prolonging the mean residence time of the drug indicating possibility of dose reduction and hence bypassing the adverse effects of TMX therapy.

Natural lipids enriched self-nano-emulsifying systems for effective co-delivery of tamoxifen and naringenin: Systematic approach for improved breast cancer therapeutics

The nano-miceller drug delivery carriers of tamoxifen (TMX) having natural ingredients like polyunsaturated fatty acid (PUFA) with self-nano-emulsifying properties was developed with naringenin (NG) in a synergistic manner i.e. TMX-NG-SNEDDS. The optimized nano-formulation revealed complete drug release in 30 min and >80% permeation in 45 min. Superior cellular uptake potential (4.6-6.5-fold) of the TMX-NG-SNEDDS using Caco-2 cells while cytotoxicity study on MCF-7 cells indicated significant results (P<0.05) of TMX-NG-SNEDDS. The in vivo pharmacokinetic study also construed remarkable improvement (7.3 and 11.4-fold increase in C_max and AUC) in rate of drug absorption and 2-fold reduction in T_max by optimized TMX-NG-SNEDDS. In vivo DMBA model construed superior efficacy of the formulation by reducing tumor size, and improved survival rate of the animals justifies its safety aspect as well.

Topologically inferring pathway activity for precise survival outcome prediction: breast cancer as a case

Accurately predicting the survival outcome of patients is of great importance in clinical cancer research. In the past decade, building survival prediction models based on gene expression data has received increasing interest. However, the existing methods are mainly based on individual gene signatures, which are known to have limited prediction accuracy on independent datasets and unclear biological relevance. Here, we propose a novel pathway-based survival prediction method called DRWPSurv in order to accurately predict survival outcome. DRWPSurv integrates gene expression profiles and prior gene interaction information to topologically infer survival associated pathway activities, and uses the pathway activities as features to construct Lasso-Cox model. It uses topological importance of genes evaluated by directed random walk to enhance the robustness of pathway activities and thereby improve the predictive performance. We applied DRWPSurv on three independent breast cancer datasets and compared the predictive performance with a traditional gene-based method and four pathway-based methods. Results showed that pathway-based methods obtained comparable or better predictive performance than the gene-based method, whereas DRWPSurv could predict survival outcome with better accuracy and robustness among the pathway-based methods. In addition, the risk pathways identified by DRWPSurv provide biologically informative models for breast cancer prognosis and treatment.

Protein regulation and Apoptotic induction in human breast carcinoma cells (MCF-7) through lectin from G. beauts

Lectins are proteins that show a variety of biological activities. Nevertheless, information on lectin from Gluttonous beauts and their anticancer activities are very limited. In this study, we purified a lectin from hemolymph of G. beauts and identified its molecular weight to be 66kDa. The effect of lectin at different concentrations (μg/mL) on the cell growth and apoptosis were evaluated against MCF-7 and MCF-10A cells, whereas cytotoxicity to the MCF-7 cells mediated by lectin was observed and the mechanism of action of the lectin in including apoptosis in cancer cells via the intrinsic pathway was also proposed. The MCF-7 cells were employed for in vitro studies on cytotoxicity, induction of apoptosis and apoptotic DNA fragmentation. In MCF-10A cells lectin did not show any adverse effect even at higher concentration. Cell cycle analysis also showed a significant cell cycle arrest on selected cells after lectin treatment. Western blotting suggested that lectin up regulates the apoptotic protein expression in MCF-7 cells while it down regulates the level of Bcl-2 expression.

Design and strategies for bile acid mediated therapy and imaging

Bioinspired materials have received substantial attention across biomedical, biological, and drug delivery research because of their high biocompatibility and lower toxicity compared with synthetic materials.

Cross-talk between bile acids and gastrointestinal tract for progression and development of cancer and its therapeutic implications

Increasing incidences of gastrointestinal (GI) cancer are linked to changes in lifestyle with excess of red meat/fat consumption, and elevated secretion of bile acids. Bile acids are strong signaling molecules that control various physiological processes. Failure in bile acid regulation has detrimental effects, often linked with development and promotion of cancer of digestive tract including esophagus, stomach, liver, and intestine. Excessive concentration of bile acids especially lipophillic secondary bile acids are cytotoxic causing apoptosis and reactive oxygen species-mediated damage to the cells. Resistance to this apoptosis and accumulation of mutations leads to progression of cancer. Cytotoxicity of bile acids is contingent on their chemical structure. In this review, we discuss the chemistry of bile acids, bile acid mediated cellular signaling processes, their role in GI cancer progression, and therapeutic potential of synthetic bile acid derivatives for cancer therapy.

Targeting mitochondrial function for the treatment of breast cancer

There are many approaches used to control breast cancer, although the most efficient strategy is the reactivation of apoptosis. Since mitochondria play an important role in cellular metabolism and homeostasis, as well as in the regulation of cell death pathways, we focus here on metabolic remodeling and mitochondrial alterations present in breast tumor cells. We review strategies including classes of compounds and delivery systems that target metabolic and specific mitochondrial alterations to kill tumor cells without affecting their normal counterparts. We present here the arguments for the improvement of already existent molecules and the design of novel promising anticancer drug candidates that target breast cancer mitochondria.

Synthesis, spectroscopy, theoretical and biological studies of new gramine-steroids salts and conjugates

New gramine connections with bile acids (lithocholic, deoxycholic, cholic) and sterols (cholesterol, cholestanol) were synthesized. The structures of products were confirmed by spectral (NMR, FT-IR) analysis, mass spectrometry (ESI-MS) as well as PM5 semiempirical methods. Unexpectedly, the products of the reaction of gramine with cholesterol and cholestanol were symmetrical compounds consisting of two molecules of sterols connected by N(CH3)2 group. All new synthesized compounds interact in vitro with the human erythrocyte membrane and alter discoid erythrocyte shape inducing stomatocytosis or echinocytosis. Increase in the incorporation of the fluorescent dye merocyanine 540 (MC540) into the erythrocyte membrane indicates that new compounds at sublytic concentrations are capable of disturbing membrane phospholipids asymmetry and loosening the molecular packing of phospholipids in the bilayer. Gramine significantly decreases the membrane partitioning properties as well as haemolytic activity of lithocholic acid in its new salt. Moreover, both deoxycholic and cholic acids completely lost their membrane perturbing activities in the gramine salts. On the other hand, the capacity of new gramine-sterols connections to alter the erythrocyte membrane structure and its permeability is much higher in comparison with sterols alone. The dual effect of gramine on the bile acid and sterols cell membrane partitioning activity observed in our study should not be neglected in vivo.

Synthesis, Structure-Activity Relationship, and Mechanistic Investigation of Lithocholic Acid Amphiphiles for Colon Cancer Therapy

We report a structure-activity relationship of lithocholic acid amphiphiles for their anticancer activities against colon cancer. We synthesized ten cationic amphiphiles differing in nature of cationic charged head groups using lithocholic acid. We observed that anticancer activities of these amphiphiles against colon cancer cell lines are contingent on nature of charged head group. Lithocholic acid based amphiphile possessing piperidine head group (LCA-PIP1 ) is ~10 times more cytotoxic as compared to its precursor. Biochemical studies revealed that enhanced activity of LCA-PIP1 as compared to lithocholic acid is due to greater activation of apoptosis.LCA-PIP1 induces sub G0 arrest and causes cleavage of caspases. A single dose of lithocholic acid-piperidine derivative is enough to reduce the tumor burden by 75% in tumor xenograft model.

Nature of the charged head group dictates the anticancer potential of lithocholic acid-tamoxifen conjugates for breast cancer therapy

Anticancer drug Tamoxifen is modified to charged lithocholic acid derived amphiphile for enhanced cytotoxicity against breast cancer cells.

Injectable small molecule hydrogel as a potential nanocarrier for localized and sustained in vivo delivery of doxorubicin

The majority of the localized drug delivery systems are based on polymeric or polypeptide scaffolds, as weak intermolecular interactions of low molecular weight hydrogelators (LMHGs, Mw <500 Da) are significantly perturbed in the presence of anticancer drugs. Here, we present l-alanine derived low molecular weight hydrogelators (LMHGs) that remain injectable even after entrapping the anticancer drug doxorubicin (DOX). These DOX containing nanoassemblies (DOX-Gel) showed promising anticancer activity in mice models. Subcutaneous injection of DOX-Gel near the tumor achieved a greater decrease in tumour load than by intravenous injection of DOX (DOX-IV), and local injection of DOX alone (DOX-Local) at the tumor site. We noticed that DOX-Gel nanocarriers are especially effective when injected during the early stage of tumor progression, and achieve a substantial decrease in tumor load in the long term.

Bile acid amphiphiles with tunable head groups as highly selective antitubercular agents

Hard-charged amphiphiles are highly selective against mycobacteria, whereas soft-charged amphiphiles are active against Gram-positive and Gram-negative bacteria.