Mechanisms of multidrug resistance in cancer

Anticancer perspectives of monocarbonyl analogs of curcumin: A decade (2014-2024) review

Monocarbonyl analogs of curcumin (MACs) represent structurally modified versions of curcumin. The existing literature indicates that MACs exhibit enhanced anticancer properties compared with curcumin. Numerous research articles in recent years have emphasized the significance of MACs as effective anticancer agents. This review focuses on the latest advances in the anticancer potential of MACs, from 2014 to 2024, including discussions on their mechanism of action, structure-activity relationship (SAR), and in silico molecular docking studies.

Harnessing machine learning potential for personalised drug design and overcoming drug resistance

Drug resistance in cancer treatment presents a significant challenge, necessitating innovative approaches to improve therapeutic efficacy. Integrating machine learning (ML) in cancer research is promising as ML algorithms outrival in analysing complex datasets, identifying patterns, and predicting treatment outcomes. Leveraging diverse data sources such as genomic profiles, clinical records, and drug response assays, ML uncovers molecular mechanisms of drug resistance, enabling personalised treatment, maximising efficacy and minimising adverse effects. Various ML algorithms contribute to the drug discovery process - Random Forest and Decision Trees predict drug-target interactions and aid in virtual screening, and SVM classify leads on bioactivity data. Neural Networks model QSAR to optimise lead compounds and K-means clustering group compounds with similar chemical properties aiding compound selection. Gaussian Processes predict drug responses, Bayesian Networks infer causal relationships, Autoencoders generate novel compounds, and Genetic Algorithms optimise molecular structures. These algorithms collectively enhance efficiency and success rates in drug design endeavours, from lead identification to optimisation and are cost-effective, empowering clinicians with real-time treatment monitoring and improving patient outcomes. This review highlights the immense potential of ML in revolutionising cancer care through effective drug design to reduce drug resistance, and we have also discussed various limitations and research gaps to understand better.

ABCG2 Mediates Resistance to the Dual EGFR and PI3K Inhibitor MTX-211 in Cancer Cells

MTX-211 is a first-in-class dual inhibitor of epidermal growth factor receptor (EGFR) and phosphoinositide-3 kinase (PI3K) signaling pathways with a compelling pharmaceutical profile and could enhance the effectiveness of mitogen-activated protein kinase kinase (MEK) inhibitor therapy in colorectal tumors with KRAS mutations. However, the specific mechanisms contributing to the acquired resistance to MTX-211 in human cancers remain elusive. Here, we discovered that the overexpression of the ATP-binding cassette (ABC) drug transporter ABCG2, a prevalent mechanism associated with multidrug resistance (MDR), could diminish the effectiveness of MTX-211 in human cancer cells. We showed that the drug efflux activity of ABCG2 substantially decreased the intracellular accumulation of MTX-211 in cancer cells. As a result, the cytotoxicity and effectiveness of MTX-211 in suppressing the activation of the EGFR and PI3K pathways were significantly attenuated in cancer cells overexpressing ABCG2. Moreover, the enhancement of the MTX-211-stimulated ATPase activity of ABCG2 and the computational molecular docking analysis illustrating the binding of MTX-211 to the substrate-binding sites of ABCG2 offered a further indication for the interaction between MTX-211 and ABCG2. In summary, our findings indicate that MTX-211 acts as a substrate for ABCG2, underscoring the involvement of ABCG2 in the emergence of resistance to MTX-211. This finding carries clinical implications and merits further exploration.

Design, synthesis, and bioactivity evaluation of novel indole-selenide derivatives as P-glycoprotein inhibitors against multi-drug resistance in MCF-7/ADR cell

The inhibition of P-glycoprotein (P-gp) has emerged as an intriguing strategy for circumventing multidrug resistance (MDR) in anticancer chemotherapy. In this study, we have designed and synthesized 30 indole-selenides as a new class of P-gp inhibitors based on the scaffold hopping strategy. Among them, the preferred compound H27 showed slightly stronger reversal activity (reversal fold: 271.7 vs 261.6) but weaker cytotoxicity (inhibition ratio: 33.7% vs 45.1%) than the third-generation P-gp inhibitor tariquidar on the tested MCF-7/ADR cells. Rh123 accumulation experiments and Western blot analysis demonstrated that H27 displayed excellent MDR reversal activity by dose-dependently inhibiting the efflux function of P-gp rather than its expression. Besides, UIC-2 reactivity shift assay revealed that H27 could bind to P-gp directly and induced a conformation change of P-gp. Moreover, docking study revealed that H27 matched well in the active pockets of P-gp by forming some key H-bonding interactions, arene-H interactions and hydrophobic contacts. These results suggested that H27 is worth to be a starting point for the development of novel Se-containing P-gp inhibitors for clinic use.

Shikonin enhances chemosensitivity of oral cancer through β-catenin pathway

OBJECTIVES

This study concentrates on exploring the synergistic effect of shikonin on cisplatin against oral cancer.

METHODS

To analyze the IC50 value of shikonin, gradient concentrations of shikonin were added to the oral cancer cell culture medium. After the cisplatin-resistant cell line was established, the effects of cisplatin and shikonin on the survival rate, proliferation, apoptosis and related pathway protein expression of common/drug-resistant oral cancer cells were compared through MTT, clone formation, flow cytometry, and Western blot experiments. β-catenin, which had the most significant expression changes, was overexpressed and silenced, and used to design a reverse validation.

RESULTS

Shikonin inhibited the viability of oral cancer cells. Although cisplatin killed some cancer cells, its effect on drug-resistant cancer cells was significantly reduced. The addition of shikonin enhanced the sensitivity of drug-resistant cells to cisplatin. Shikonin regulated key proteins in cell proliferation and apoptosis-related pathways. Among them, shikonin generated the most evident inhibitory effect on β-catenin. Therefore, β-catenin overexpression plasmid/siβ-catenin was transfected into the cells. Silenced β-catenin was found to reinforce the damaging effect of cisplatin on cancer cells, and overexpressed β-catenin reversed the effect of shikonin.

CONCLUSION

By down-regulating β-catenin expression, shikonin improves the sensitivity of drug-resistant oral cancer cells to cisplatin.

Graphene oxide nanosheets conjugated PEG-Glu-Lys-Glu copolymer drug delivery system improves drug-loading rates and enables reduction-sensitive drug release and drug tracking

In this study, the PEG-Glu-Lys-Glu copolymer drug delivery system (GO/PEG-Glu-Lys-Glu) is prepared using glutamate-lysine-glutamate (Glu-Lys-Glu) modified polyethylene glycol (PEG) and connected graphene oxide nanosheets (GO). The multiple carboxyl groups of Glu-Lys-Glu and π-π interactions of GO can increase drug loading rate, and the fluorescence characteristics of GO could monitor the distribution of drug-loading systems in cells and the uptake of cells without the need for external dyes. Paclitaxel (PTX) is loaded via reduction-responsive disulfide bonds as a model medicine to examine the drug delivery potential of GO/PEG-Glu-Lys-Glu. The results showed that the drug loading content of PEG-Glu-Lys-Glu and GO/PEG-Glu-Lys-Glu to PTX is 7.11% and 8.97%, and the loading efficiency is 71.05% and 89.68%, respectively. It's speculated that the π-π interaction between GO and PTX improved the drug-loading capacity and efficiency of GO/PEG-Glu-Lys-Glu. In vitro, in a simulated drug release test, at 48 h, the release of PTX was 85.51% at pH 5.0, 65.12% and 38.32% at pH 6.5 and 7.4, respectively. The cytotoxicity assay results showed that GO/PEG-Glu-Lys-Glu cell inhibition rate to MCF-7 cells was 7.36% at 72 h. The cell inhibition rate of GO/PEG-Glu-Lys-Glu/PTX system at 72 h was 92%, equivalent to free PTX. Therefore, the GO/PEG-Glu-Lys-Glu drug delivery system has the characteristics of good biocompatibility and sustainable release of PTX, which is expected to be applied in the field of tumor therapy.

Unveiling the potential anti-cancer activity of calycosin against multivarious cancers with molecular insights: A promising frontier in cancer research

BACKGROUND

Calycosin may be a potential candidate regarding chemotherapeutic agent, because already some studies against multivarious cancer have been made with this natural compound.

AIM

This review elucidated a brief overview of previous studies on calycosin potential effects on various cancers and its potential mechanism of action.

METHODOLOGY

Data retrieved by systematic searches of Google Scholar, PubMed, Science Direct, Web of Science, and Scopus by using keywords including calycosin, cancer types, anti-cancer mechanism, synergistic, and pharmacokinetic and commonly used tools are BioRender, ChemDraw Professional 16.0, and ADMETlab 2.0.

RESULTS

Based on our review, calycosin is available in nature and effective against around 15 different types of cancer. Generally, the anti-cancer mechanism of this compound is mediated through a variety of processes, including regulation of apoptotic pathways, cell cycle, angiogenesis and metastasis, oncogenes, enzymatic pathways, and signal transduction process. These study conducted in various study models, including in silico, in vitro, preclinical and clinical models. The molecular framework behind the anti-cancer effect is targeting some oncogenic and therapeutic proteins and multiple signaling cascades. Therapies based on nano-formulated calycosin may make excellent nanocarriers for the delivery of this compound to targeted tissue as well as particular organ. This natural compound becomes very effective when combined with other natural compounds and some standard drugs. Moreover, proper use of this compound can reverse resistance to existing anti-cancer drugs through a variety of strategies. Calycosin showed better pharmacokinetic properties with less toxicity in human bodies.

CONCLUSION

Calycosin exhibits excellent potential as a therapeutic drug against several cancer types and should be consumed until standard chemotherapeutics are available in pharma markets.

SIVA-1 enhances acquired chemotherapeutic drug resistance of gastric cancer in vivo by regulating the ARF/MDM2/p53 pathway

SIVA-1 has been shown to affect apoptotic processes in various different cell lines, and SIVA-1 significantly contributes to the decreased responsiveness of cancer cells to some chemotherapy agents. However, whether SIVA-1 has potential application in gastric cancer remains unknown. Therefore, the objective of this investigation was to clarify the distinct function of SIVA-1 in chemotherapeutic drug resistance within a living murine model with gastric malignancy, and initially elucidate the underlying mechanisms. In an established multidrug-resistant gastric cancer xenograft mouse model, lentivirus, named Lv-SIVA-1, was injected into xenograft tumors, and increased the mRNA and protein expression of endogenous SIVA-1 in tumors. Immunohistochemical assays of xenograft tumor showed that SIVA-1 was significantly upregulated, and the protein expression levels of SIVA-1 were highly increased, as detected by Western blotting. In addition, we detected the role of SIVA-1 in cell proliferation and cell apoptosis in gastric cancer cells by TUNEL and found that SIVA-1 decreased tumor cell apoptosis and promoted tumor growth in vivo. Using a TMT assay between tumor tissues of experimental and control groups, differentially expressed proteins were examined and three potential biomarkers of multidrug resistance (ARF, MDM2, and p53) were screened. We further investigated the molecular mechanism by which SIVA-1 played an efficient role against chemotherapies and found that overexpressed SIVA-1 leads to increased ARF and MDM2 expression and suppressed expression of p53 in tumor tissue. In conclusion, SIVA-1 plays a significant role in the multidrug resistance of gastric tumors. In addition, overexpressed SIVA-1 positively regulates cell proliferation, adjusts cycle progression, and reduces the response to drug treatment for gastric cancer in an ARF/MDM2/p53-dependent manner. This novel research provides a basis for chemical management of gastric cancer through regulation of SIVA-1 expression.

Imperatorin Restores Chemosensitivity of Multidrug-Resistant Cancer Cells by Antagonizing ABCG2-Mediated Drug Transport

The high expression of the ATP-binding cassette (ABC) drug transporter ABCG2 in cancer cells contributes to the emergence of multidrug resistance (MDR) in individuals afflicted with either solid tumors or blood cancers. MDR poses a major impediment in the realm of clinical cancer chemotherapy. Recently, substantial endeavors have been dedicated to identifying bioactive compounds isolated from nature capable of counteracting ABCG2-mediated MDR in cancer cells. Imperatorin, a natural coumarin derivative renowned for its diverse pharmacological properties, has not previously been explored for its impact on cancer drug resistance. This study investigates the chemosensitizing potential of imperatorin in ABCG2-overexpressing cancer cells. Experimental results reveal that at sub-toxic concentrations, imperatorin significantly antagonizes the activity of ABCG2 and reverses ABCG2-mediated MDR in a concentration-dependent manner. Furthermore, biochemical data and in silico analysis of imperatorin docking to the inward-open conformation of human ABCG2 indicate that imperatorin directly interacts with multiple residues situated within the transmembrane substrate-binding pocket of ABCG2. Taken together, these results furnish substantiation that imperatorin holds promise for further evaluation as a potent inhibitor of ABCG2, warranting exploration in combination drug therapy to enhance the effectiveness of therapeutic agents for patients afflicted with tumors that exhibit high levels of ABCG2.

Exosome engineering for efficient and targeted drug delivery: Current status and future perspective

Exosomes are membrane-bound vesicles that are released by most cells. They carry nucleic acids, cytokines, growth factors, proteins, lipids, and metabolites. They are responsible for inter- and intracellular communications and their role in drug delivery is well defined. Exosomes have great potential for therapeutic applications, but the clinical use is restricted because of limitations in standardized procedures for isolation, purification, and drug delivery. Bioengineering of exosomes could be one approach to achieve standardization and reproducible isolation for clinical use. Exosomes are important transporters for targeted drug delivery because of their small size, stable structure, non-immunogenicity, and non-toxic nature, as well as their ability to carry a wide variety of compounds. These features of exosomes can be enhanced further by bioengineering. In this review, possible exosome bioengineering approaches, their biomedical applications, and targeted drug delivery are discussed.

Perspectives on drug repurposing to overcome cancer multidrug resistance mediated by ABCB1 and ABCG2

The overexpression of the human ATP-binding cassette (ABC) transporters in cancer cells is a common mechanism involved in developing multidrug resistance (MDR). Unfortunately, there are currently no approved drugs specifically designed to treat multidrug-resistant cancers, making MDR a significant obstacle to successful chemotherapy. Despite over two decades of research, developing transporter-specific inhibitors for clinical use has proven to be a challenging endeavor. As an alternative approach, drug repurposing has gained traction as a more practical method to discover clinically effective modulators of drug transporters. This involves exploring new indications for already-approved drugs, bypassing the lengthy process of developing novel synthetic inhibitors. In this context, we will discuss the mechanisms of ABC drug transporters ABCB1 and ABCG2, their roles in cancer MDR, and the inhibitors that have been evaluated for their potential to reverse MDR mediated by these drug transporters. Our focus will be on providing an up-to-date report on approved drugs tested for their inhibitory activities against these drug efflux pumps. Lastly, we will explore the challenges and prospects of repurposing already approved medications for clinical use to overcome chemoresistance in patients with high tumor expression of ABCB1 and/or ABCG2.

Nitric oxide/paclitaxel micelles enhance anti-liver cancer effects and paclitaxel sensitivity by inducing ferroptosis, endoplasmic reticulum stress and pyroptosis

The objective of this study was to investigate the anticancer activities of biodegradable polymeric micelles composed of monomethoxy poly(ethylene glycol), polylactic acid, and nitric oxide (mPEG-PLA-NO) loaded with paclitaxel (PTX) as a nanomedicine delivery system. We aimed to compare the anticancer effects of these NO/PTX micelles with PTX alone and elucidate their mechanism of action. We evaluated the impact of NO/PTX and PTX on cell viability using Cell Counting Kit-8 (CCK8) assays conducted on the Bel-7402 liver cancer cell line. Additionally, we employed H22 xenografted mice to assess the in vivo tumor growth inhibitory activity of NO/PTX. To examine the cytotoxicity of NO/PTX, the intracellular levels of reactive oxygen species (ROS), and the expression of ferroptosis-related proteins, we conducted experiments in the presence of the ferroptosis inhibitor ferrostatin-1 (Fer-1) or the ROS inhibitor N-acetyl cysteine (NAC). Furthermore, we investigated the expression of endoplasmic reticulum stress (ERS) and apoptosis-associated proteins. Our results demonstrated that NO/PTX exhibited enhanced anticancer effects compared to PTX alone in both Bel-7402 cells and H22 xenografted mice. The addition of Fer-1 or NAC reduced the anticancer activity of NO/PTX, indicating the involvement of ferroptosis and ROS in its mechanism of action. Furthermore, NO/PTX modulated the expression of proteins related to ERS and apoptosis, indicating the activation of these cellular pathways. The anticancer effects of NO/PTX in liver cancer cells were mediated through the induction of ferroptosis, pyroptosis, ERS, and apoptosis-associated networks. Ferroptosis and pyroptosis were activated by treatment of NO/PTX at low concentration, whereas ERS was induced to trigger apoptosis at high concentration. The superior anti-tumor effect of NO/PTX may be attributed to the downregulation of a multidrug resistance transporter and the sensitization of cells to PTX chemotherapy. In summary, our study highlights the potential of mPEG-PLA-NO micelles loaded with PTX as a nanomedicine delivery system for liver cancer treatment. The observed enhancement in anticancer activity, combined with the modulation of key cellular pathways, provides valuable insights into the therapeutic potential of NO/PTX in overcoming resistance and improving treatment outcomes in liver cancer patients.

The PAPSS1 gene is a modulator of response to cisplatin by regulating estrogen receptor alpha signaling activity in ovarian cancer cells

BACKGROUND

Cancer cells may develop resistance to cisplatin by various mechanisms. Yet, the exact mechanism of cisplatin in ovarian cancer remains unclear. Recent studies have shown that 3'-phospoadenosine 5'-phosphosulfate synthase 1 (PAPSS1) inhibition combined with low-dose cisplatin increases DNA damage. The aim of this study was to determine the value of targeting PAPSS1 as a cisplatin modulator in epithelial ovarian cancer (EOC).

RESULTS

Increased expression of PAPSS1 was observed in both EOC cells and tissues. Also, its higher nuclear expression was distinctly associated with FIGO (The International Federation of Gynecology and Obstetrics) stage, histological subtype, metastasis, and recurrence. Down-regulation of the PAPSS1 gene increased the cisplatin sensitivity of EOC in vitro and in vivo. Expression of PAPSS1 was negatively correlated with estrogen receptor α (ERα) in EOC. Also, low nuclear PAPSS1 and high nuclear ERα expression in EOC were associated with longer overall survival and progression-free survival in all ovarian cancer and ovarian cancer patients who received platinum-based chemotherapy. PAPSS1 silencing increased the activity of ERα-signaling in EOC cells, thus sensitizing tumors to cisplatin.

CONCLUSIONS

These findings characterize a novel interplay between PAPSS1-mediated sulfation and ERα-signaling in EOC cisplatin resistance. PAPSS1 may be exploited as a cisplatin-sensitizing therapeutic target.

Advances of medical nanorobots for future cancer treatments

Early detection and diagnosis of many cancers is very challenging. Late stage detection of a cancer always leads to high mortality rates. It is imperative to develop novel and more sensitive and effective diagnosis and therapeutic methods for cancer treatments. The development of new cancer treatments has become a crucial aspect of medical advancements. Nanobots, as one of the most promising applications of nanomedicines, are at the forefront of multidisciplinary research. With the progress of nanotechnology, nanobots enable the assembly and deployment of functional molecular/nanosized machines and are increasingly being utilized in cancer diagnosis and therapeutic treatment. In recent years, various practical applications of nanobots for cancer treatments have transitioned from theory to practice, from in vitro experiments to in vivo applications. In this paper, we review and analyze the recent advancements of nanobots in cancer treatments, with a particular emphasis on their key fundamental features and their applications in drug delivery, tumor sensing and diagnosis, targeted therapy, minimally invasive surgery, and other comprehensive treatments. At the same time, we discuss the challenges and the potential research opportunities for nanobots in revolutionizing cancer treatments. In the future, medical nanobots are expected to become more sophisticated and capable of performing multiple medical functions and tasks, ultimately becoming true nanosubmarines in the bloodstream.

Hsa_circ_0003220 Drives Chemoresistance of Human NSCLC Cells by Modulating miR-489-3p/IGF1

Circular RNAs (circRNAs) have been shown to have critical roles in developing cancer and treatment resistance in an increasing body of research. The aim was to look into the functions and processes of hsa_circ_0003220 in the non-small cell lung cancer (NSCLC) chemoresistance. The NSCLC cell lines H460 and A549 were employed in present work. hsa_circ_0003220, miR-489-3p, and insulin-like growth factors (IGF1) mRNA levels were assessed with a quantitative real time polymerase chain reaction (qRT-PCR). The cisplatin, docetaxel, and paclitaxel (PTX) resistances were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the enzyme linked immunosorbent assay (ELISA) test measured IGF1 expression. In order to corroborate the miR-489-3p relation with hsa_circ_0003220 or IGF1, a dual-luciferase reporter method was applied. The level of hsa_circ_0003220 was raised in cells and tissues from PTX-resistant (PR) NSCLC. In PR NSCLC cells, hsa_circ_0003220 knockdown reduced chemoresistance. For the purpose of the mechanism study, hsa_circ_0003220 knockdown substantially reduced IGF1 expression via miR-489-3p sponging, reducing chemoresistance in PR NSCLC cells. By controlling the miR-489-3p/IGF1 axis, hsa_circ_0003220 knockdown helped NSCLC overcome chemoresistance, suggesting a potential circRNA-targeted therapy for the disease.

Nanomedicine Technologies for Diagnosis and Treatment of Breast Cancer

Breast cancer is one of the most common cancers in women worldwide, yet conventional treatments have several shortcomings, including low specificity, systemic toxicity, and drug resistance. Nanomedicine technologies provide a promising alternative while also overcoming the limitations posed by conventional therapies. This mini-Review highlights important signaling pathways related to occurrence and development of breast cancer and current breast cancer therapies, followed by an analysis of various nanomedicine technologies developed for diagnosis and treatment of breast cancers.

Two curcumin analogs inhibited the function and protein expression of breast cancer resistance protein: in vitro and in vivo studies

1. Two curcumin analogs, (1E,6E)-1,7-bis(3,5-diethyl-4-hydroxyphenyl)hepta-1,6-diene-3,5- dione (N17) and its prodrug ((1E,6E)-3,5-dioxohepta-1,6-diene-1,7-diyl)bis(2,6-diethyl-4,1- phenylene)bis(3-hydroxy-2-(hydroxymethyl)-2-methylpropanoate) (N17'), were evaluated as breast cancer resistance protein (BCRP) inhibitors.2. MDCKII-BCRP and MDCKII-WT were used to evaluate the modulation effects of N17 and N17' on BCRP and to explore the relevant mechanism. Sprague-Dawley rats were orally administered rosuvastatin (ROS), a probe substrate of BCRP, without and with N17' (100 mg/kg) to investigate the effect of N17' on ROS pharmacokinetics.3. In cell studies, N17 and N17' were substrates of BCRP, and they decreased the activity and protein expression of BCRP. In rat study, N17' increased the systemic exposure of ROS by 218% (p = 0.058).4. N17 and N17' are potential BCRP inhibitors and will be promising candidates for overcoming the BCRP-mediated multidrug resistance.

ABCB1 and ABCG2 Overexpression Mediates Resistance to the Phosphatidylinositol 3-Kinase Inhibitor HS-173 in Cancer Cell Lines

Constitutive activation of the phosphoinositide-3-kinase (PI3K)/Akt signaling pathway is crucial for tumor growth and progression. As such, this pathway has been an enticing target for drug discovery. Although HS-173 is a potent PI3K inhibitor that halts cancer cell proliferation via G2/M cell cycle arrest, the resistance mechanisms to HS-173 have not been investigated. In this study, we investigated the susceptibility of HS-173 to efflux mediated by the multidrug efflux transporters ABCB1 and ABCG2, which are two of the most well-known ATP-binding cassette (ABC) transporters associated with the development of cancer multidrug resistance (MDR). We found that the overexpression of ABCB1 or ABCG2 significantly reduced the efficacy of HS-173 in human cancer cells. Our data show that the intracellular accumulation of HS-173 was substantially reduced by ABCB1 and ABCG2, affecting G2/M arrest and apoptosis induced by HS-173. More importantly, the efficacy of HS-173 in multidrug-resistant cancer cells could be recovered by inhibiting the drug-efflux function of ABCB1 and ABCG2. Taken together, our study has demonstrated that HS-173 is a substrate for both ABCB1 and ABCG2, resulting in decreased intracellular concentration of this drug, which may have implications for its clinical use.

Functionalized Lipid Nanocarriers for Simultaneous Delivery of Docetaxel and Tariquidar to Chemoresistant Cancer Cells

The simultaneous drug delivery efficiency of a co-loaded single-carrier system of docetaxel (DTX)- and tariquidar (TRQ)-loaded nanostructured lipid carrier (NLC) functionalized with PEG and RIPL peptide (PRN) (D^T-PRN) was compared with that of a physically mixed dual-carrier system of DTX-loaded PRN (D-PRN) and TRQ-loaded PRN (T-PRN) to overcome DTX mono-administration-induced multidrug resistance. NLC samples were prepared using the solvent emulsification evaporation technique and showed homogeneous spherical morphology, with nano-sized dispersion (<220 nm) and zeta potential values of −15 to −7 mV. DTX and/or TRQ was successfully encapsulated in NLC samples (>95% encapsulation efficiency and 73–78 µg/mg drug loading). In vitro cytotoxicity was concentration-dependent; D^T-PRN exhibited the highest MDR reversal efficiency, with the lowest combination index value, and increased the cytotoxicity and apoptosis in MCF7/ADR cells by inducing cell-cycle arrest in the G2/M phase. A competitive cellular uptake assay using fluorescent probes showed that, compared to the dual nanocarrier system, the single nanocarrier system exhibited better intracellular delivery efficiency of multiple probes to target cells. In the MCF7/ADR-xenografted mouse models, simultaneous DTX and TRQ delivery using D^T-PRN significantly suppressed tumor growth as compared to other treatments. A single co-loaded system for PRN-based co-delivery of DTX/TRQ (1:1, w/w) constitutes a promising therapeutic strategy for drug-resistant breast cancer cells.

Engineered Biosensors for Diagnosing Multidrug Resistance in Microbial and Malignant Cells

To curtail pathogens or tumors, antimicrobial or antineoplastic drugs have been developed. These drugs target microbial/cancer growth and survival, thereby improving the host's health. In attempts to evade the detrimental effects of such drugs, these cells have evolved several mechanisms over time. Some variants of the cells have developed resistances against multiple drugs or antimicrobial agents. Such microorganisms or cancer cells are said to exhibit multidrug resistance (MDR). The drug resistance status of a cell can be determined by analyzing several genotypic and phenotypic changes, which are brought about by significant physiological and biochemical alterations. Owing to their resilient nature, treatment and management of MDR cases in clinics is arduous and requires a meticulous approach. Currently, techniques such as plating and culturing, biopsy, gene sequencing, and magnetic resonance imaging are prevalent in clinical practices for determining drug resistance status. However, the major drawbacks of using these methods lie in their time-consuming nature and the problem of translating them into point-of-care or mass-detection tools. To overcome the shortcomings of conventional techniques, biosensors with a low detection limit have been engineered to provide quick and reliable results conveniently. These devices are highly versatile in terms of analyte range and quantities that can be detected to report drug resistance in a given sample. A brief introduction to MDR, along with a detailed insight into recent biosensor design trends and use for identifying multidrug-resistant microorganisms and tumors, is presented in this review.

Computational analysis and in vitro evaluation of TMF 104, for its antioxidant, antimicrobial, and anticancer efficacies

Benzylidene chromanones are small molecules, structurally similar to active phytochemicals. Herein, we report one novel benzylidene chromanone, TMF 104, for its bio-efficacies. Its computational docking for Vanin-1, antioxidant, free radical scavenging capacities, antimicrobial effects, and anticancer efficacy were analyzed. TMF 104 predicated strong binging to Vanin-1 protein with a docking energy of -8.1 kcal/mol. The compound dose-dependently exhibited free-radical scavenging and antioxidant activities when tested in vitro. The compound also had remarkable activity against Salmonella typhimurium, Enterococcus faecalis, Staphylococcus aureus, and Escherichia coli with minimum inhibitory concentration values of 1.5, 2.0, 12.5, and 13.5 μg/ml, respectively. The compound was also effective against Bacillus cereus and Pseudomonas aeruginosa albeit at higher concentrations. TMF 104 dose-dependently inhibited the proliferation of MCF-7, NCI H460, and Caki-1 cells with respective GI₅₀ values of 24.51, 21.95, and 32.95 μg/ml, whereas the compound was toxic to normal Vero cells at much higher concentration of 264.70 μg/ml. The compound also aided in apoptosis and increased the sub G₀ /G₁ phase of the cell cycle in all three cancer cells tested. Our study identified a novel, potent benzylidene analogue with potent antioxidant, antimicrobial, and anticancer activities, which drives further attention for further research.

Acoustically-Activated Liposomal Nanocarriers to Mitigate the Side Effects of Conventional Chemotherapy with a Focus on Emulsion-Liposomes

To improve currently available cancer treatments, nanomaterials are employed as smart drug delivery vehicles that can be engineered to locally target cancer cells and respond to stimuli. Nanocarriers can entrap chemotherapeutic drugs and deliver them to the diseased site, reducing the side effects associated with the systemic administration of conventional anticancer drugs. Upon accumulation in the tumor cells, the nanocarriers need to be potentiated to release their therapeutic cargo. Stimulation can be through endogenous or exogenous modalities, such as temperature, electromagnetic irradiation, ultrasound (US), pH, or enzymes. This review discusses the acoustic stimulation of different sonosensitive liposomal formulations. Emulsion liposomes, or eLiposomes, are liposomes encapsulating phase-changing nanoemulsion droplets, which promote acoustic droplet vaporization (ADV) upon sonication. This gives eLiposomes the advantage of delivering the encapsulated drug at low intensities and short exposure times relative to liposomes. Other formulations integrating microbubbles and nanobubbles are also discussed.

Unravelling the enigma of siRNA and aptamer mediated therapies against pancreatic cancer

Pancreatic cancer (PC) is a fatal disease that has a poor 5-year survival rate. The poor prognosis can be attributed to both troublesome detections at the initial stage, which makes the majority of the treatment options largely unsuccessful and leads to extensive metastasis, as well as to its distinct pathophysiological characteristics, such as rich desmoplastic tumours bounded by dysplastic and hypo perfused vessels restricting the mobility of therapeutic agents. Continued attempts have been made to utilise innovative measures for battling PC to increase the therapeutic effectiveness of therapies and overcome their cytotoxicity. Combined cancer targeting and gene silencing approach has shown improved outcomes in patients' survival rates and quality of life, offering a potential solution to therapeutic complications. It particularly targets various barriers to alleviate delivery problems and diminish tumour recurrence and metastasis. While aptamers, a type of single-stranded nucleic acids with strong binding affinity and specificity to target molecules, have recently surfaced as a viable PC strategy, siRNA can interfere with the expression of certain genes. By concurrently suppressing genes and boosting targeted approach, the cocktail of siRNA/Aptamer and other therapeutic drugs can circumvent the multi-drug resistance phenomena. Additionally, combination therapy with additive or synergistic effects can considerably increase the therapeutic efficacy of anti-cancer medications. This study outlines the primary difficulties in treating PC, along with recent developments in siRNA/Aptamer mediated drug delivery to solve the major hiccup of oncology field.

Analysis of Changes in the Expression of Selected Genes from the ABC Family in Patients with Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is characterized by a lack of expression of hormone receptors (estrogen and progesterone), as cancer cells also do not overexpress the HER2 receptor. Due to their molecular profile, treatments for this type of breast cancer are limited. In some cases, the pharmacotherapy of patients with TNBC is hindered by the occurrence of multidrug resistance, which is largely conditioned by proteins encoded by genes from the ABC family. The aim of our study was to determine the expression profile of 14 selected genes from the ABC family using real-time PCR in 68 patients with TNBC by comparing the obtained results with clinical data and additionally using bioinformatics tools (Ualcan and The Breast Cancer Gene Expression Miner v4.8 (bc -GenExMiner v4.8)), as well as by comparing experimental data with data in the Cancer Genome Atlas (TCGA) database. Based on the conducted studies, we found different levels of gene expression depending on the age of patients, tumor sizes, metastases to lymph nodes, cell infiltration into adipose tissue, tumor stages, or lymphovascularinvasion. The results of the presented studies demonstrate the effect of the expression level of the studied genes on the clinical course and prognosis of patients with TNBC, and suggest how profiling the expression level of genes from the ABC family may be a useful tool in determining personalized TNBC treatment.

Hybrids of thiazolidinone with 1,2,3-triazole derivatives: design, synthesis, biological evaluation, in silico studies, molecular docking, molecular dynamics simulations, and ADMET profiling

A new series of thiazolidinone linked 1,2,3-triazole hybrids 5a-h was designed and synthesized using the copper-catalyzed Huisgen azide-alkyne cycloaddition (CuAAC) between thiazolidinone linked alkyne and aromatic azides. The structures of the newly synthesized compounds were established by NMR (1H and 13C) and HRMS. The targeted thiazolidinone-1,2,3-triazole hybrids were evaluated for their cytotoxic activity against four human cancer cell lines, including fibrosarcoma (HT-1080), lung carcinoma (A-549), and breast carcinoma (MCF-7 and MDA-MB-231) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliun bromide (MTT). The obtained data showed that most of these compounds have moderate anti-proliferative activity with IC50 values between 10.26 ± 0.71 and 53.93 ± 1.20 μM. The compound 5a exhibited higher activity with an IC50 value of 10.26 ± 0.71 µM, compared to 5d with an IC50 value of 11.56 ± 1.98 µM for the HT-1080 and MCF-7 cancer cells line, respectively. Moreover, Annexin-V apoptosis was assessed by flow cytometry for hybrid compounds 5a and 5d against HT-1080 and MCF-7 competitor cell lines, as they increase the level of active caspase 3/7. The experimental results were further confirmed by docking studies followed by molecular dynamic simulations. Both the potent derivatives i.e. 5a and 5d have comparable docking scores and MD simulations results showed that the docked complex of 5a is somewhat more stable than 5d primarily for protein p53. The ADMET profile of both derivatives established their safety zone and drug-like potential.Communicated by Ramaswamy H. Sarma.

Quantification of spatial pharmacogene expression heterogeneity in breast tumors

BACKGROUND

Chemotherapeutic drug concentrations vary across different regions of tumors and this is thought to be involved in development of chemotherapy resistance. Insufficient drug delivery to some regions of the tumor may be due to spatial differences in expression of genes involved in the disposition, transport, and detoxification of drugs (pharmacogenes). Therefore, in this study, we analyzed the spatial expression of 286 pharmacogenes in six breast cancer tissues using the recently developed Visium spatial transcriptomics platform to (1) determine if these pharmacogenes are expressed heterogeneously across tumor tissue and (2) to determine which pharmacogenes have the most spatial expression heterogeneity.

METHODS AND RESULTS

The spatial transcriptomics technology sequences the transcriptome of 55 um diameter barcoded sections (spots) across a tissue sample. We analyzed spatial gene expression profiles of four biobank-sourced breast tumor samples in addition to two breast tumor sample datasets from 10× Genomics. We define heterogeneity as the interquartile range of read counts. Collectively, we identified 8887 spots in tumor regions, 3814 in stroma, 44 in lymphocytes, and 116 in normal regions based on pathologist annotation of the tissues. We showed statistically significant differences in expression of pharmacogenes in tumor regions compared to surrounding non-tumor regions. We also observed that the most heterogeneously expressed genes within tumor regions were involved in reactive oxygen species (ROS) handling and detoxification mechanisms. GPX4, GSTP1, MGST3, SOD1, CYP4Z1, CYB5R3, GSTK1, and NAT1 showed the most heterogeneous expression within tumor regions.

CONCLUSIONS

The heterogeneous expression of these pharmacogenes may have important implications for cancer therapy due to their ability to impact drug distribution and efficacy throughout the tumor. Our results suggest that chemoresistance caused by expression of GPX4, GSTP1, MGST3, and SOD1 may be intrinsic, not acquired, since the heterogeneity is not specific to chemotherapy-treated samples or cell type. Additionally, we identified candidate chemoresistance pharmacogenes that can be further tested through focused follow-up studies.

Exploring novel fluorine-rich fuberidazole derivatives as hypoxic cancer inhibitors: Design, synthesis, pharmacokinetics, molecular docking, and DFT evaluations

Sixteen fuberidazole derivatives as potential new anticancer bioreductive prodrugs were prepared and characterized. The in vitro anticancer potential was examined to explore their cytotoxic properties by employing apoptosis, DNA damage, and proliferation tests on chosen hypoxic cancer cells. Eight substances (Compound 5a, 5c, 5d, 5e, 5g, 5h, 5i, and 5m) showed promising cytotoxicity values compared to the standard control. The potential of compounds was also examined through in silico studies (against human serum albumin), including chem-informatics, to understand the structure-activity relationship (SAR), pharmacochemical strength, and the mode of interactions responsible for their action. The DFT calculations revealed that only the 5b compound showed the lowest ΔET (2.29 eV) while 5i showed relatively highest βtot (69.89 x 10-31 esu), highest αave (3.18 x 10-23 esu), and dipole moment (6.49 Debye). This study presents a novel class of fuberidazole derivatives with selectivity toward hypoxic cancer cells.

Phytochemical, Antimicrobial, Antioxidant, and In Vitro Cytotoxicity Evaluation of Echinops erinaceus Kit Tan

Wild plants are used by many cultures for the treatment of diverse ailments. However, they are formed from mixtures of many wanted and unwanted phytochemicals. Thus, there is a necessity to separate the bioactive compounds responsible for their biological activity. In this study, the chemical composition as well as antimicrobial and cytotoxic activities of Echinops erinaceus Kit Tan (Asteraceae) were investigated. This led to the isolation and identification of seven compounds, two of which are new (erinaceosin C3 and erinaceol C5), in addition to methyl oleate (C1) and ethyl oleate (C2), loliolide (C4), (E)-p-coumaric acid (C6), and 5,7,3`,5`-tetrahydroxy flavanone (C7). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HR-ESI-MS. The methanol extract showed the highest antimicrobial activity among the tested extracts and fractions. The n-hexane and EtOAc extracts showed remarkable antimicrobial activity against B. subtilus, P. aeruginosa, E. coli, and C. albicans. A cytotoxicity-guided fractionation of the most bioactive chloroform extract resulted in the isolation of bioactive compounds C1/C2, which showed significant cytotoxicity against HCT-116 and CACO2 cell lines (IC50 24.95 and 19.74 µg/mL, respectively), followed by compounds C3 (IC50 82.82 and 76.70 µg/mL) and C5 (IC50 99.09 and 87.27 µg/mL), respectively. The antioxidant activity of the bioactive chloroform fractions was screened. Molecular docking was used to explain the results of the antimicrobial and anticancer activities against five protein targets, including DNA gyrase topoisomerase II, enoyl-acyl carrier protein reductase of S. aureus (FabI), dihydrofolate reductase (DHFR), β-catenin, and human P-glycoprotein (P-gp).

Proton-coupled monocarboxylate transporters in cancer: From metabolic crosstalk, immunosuppression and anti-apoptosis to clinical applications

The Warburg effect is known as the hyperactive glycolysis that provides the energy needed for rapid growth and proliferation in most tumor cells even under the condition of sufficient oxygen. This metabolic pattern can lead to a large accumulation of lactic acid and intracellular acidification, which can affect the growth of tumor cells and lead to cell death. Proton-coupled monocarboxylate transporters (MCTs) belong to the SLC16A gene family, which consists of 14 members. MCT1-4 promotes the passive transport of monocarboxylate (e.g., lactate, pyruvate, and ketone bodies) and proton transport across membranes. MCT1-4-mediated lactate shuttling between glycolytic tumor cells or cancer-associated fibroblasts and oxidative tumor cells plays an important role in the metabolic reprogramming of energy, lipids, and amino acids and maintains the survival of tumor cells. In addition, MCT-mediated lactate signaling can promote tumor angiogenesis, immune suppression and multidrug resistance, migration and metastasis, and ferroptosis resistance and autophagy, which is conducive to the development of tumor cells and avoid death. Although there are certain challenges, the study of targeted drugs against these transporters shows great promise and may form new anticancer treatment options.

Biomimetic antimicrobial polymers—Design, characterization, antimicrobial, and novel applications

Biomimetic antimicrobial polymers have been an area of great interest as the need for novel antimicrobial compounds grows due to the development of resistance. These polymers were designed and developed to mimic naturally occurring antimicrobial peptides in both physicochemical composition and mechanism of action. These antimicrobial peptide mimetic polymers have been extensively investigated using chemical, biophysical, microbiological, and computational approaches to gain a deeper understanding of the molecular interactions that drive function. These studies have helped inform SARs, mechanism of action, and general physicochemical factors that influence the activity and properties of antimicrobial polymers. However, there are still lingering questions in this field regarding 3D structural patterning, bioavailability, and applicability to alternative targets. In this review, we present a perspective on the development and characterization of several antimicrobial polymers and discuss novel applications of these molecules emerging in the field. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.

Breast Cancer with Increased Drug Resistance, Invasion Ability, and Cancer Stem Cell Properties through Metabolism Reprogramming

Breast cancer is a heterogeneous disease, and the survival rate of patients with breast cancer strongly depends on their stage and clinicopathological features. Chemoradiation therapy is commonly employed to improve the survivability of patients with advanced breast cancer. However, the treatment process is often accompanied by the development of drug resistance, which eventually leads to treatment failure. Metabolism reprogramming has been recognized as a mechanism of breast cancer resistance. In this study, we established a doxorubicin-resistant MCF-7 (MCF-7-D500) cell line through a series of long-term doxorubicin in vitro treatments. Our data revealed that MCF-7-D500 cells exhibited increased multiple-drug resistance, cancer stemness, and invasiveness compared with parental cells. We analyzed the metabolic profiles of MCF-7 and MCF-7-D500 cells through liquid chromatography−mass spectrometry. We observed significant changes in 25 metabolites, of which, 21 exhibited increased levels (>1.5-fold change and p < 0.05) and 4 exhibited decreased levels (<0.75-fold change and p < 0.05) in MCF-7 cells with doxorubicin resistance. These results suggest the involvement of metabolism reprogramming in the development of drug resistance in breast cancer, especially the activation of glycolysis, the tricarboxylic acid (TCA) cycle, and the hexamine biosynthesis pathway (HBP). Furthermore, most of the enzymes involved in glycolysis, the HBP, and the TCA cycle were upregulated in MCF-7-D500 cells and contributed to the poor prognosis of patients with breast cancer. Our findings provide new insights into the regulation of drug resistance in breast cancer, and these drug resistance-related metabolic pathways can serve as targets for the treatment of chemoresistance in breast cancer.

Hydroxygenkwanin Improves the Efficacy of Cytotoxic Drugs in ABCG2-Overexpressing Multidrug-Resistant Cancer Cells

Hydroxygenkwanin, a flavonoid isolated from the leaves of the Daphne genkwa plant, is known to have pharmacological properties; however, its modulatory effect on multidrug resistance, which is (MDR) mediated by ATP-binding cassette (ABC) drug transporters, has not been investigated. In this study, we examine the interaction between hydroxygenkwanin, ABCB1, and ABCG2, which are two of the most well-characterized ABC transporters known to contribute to clinical MDR in cancer patients. Hydroxygenkwanin is not an efflux substrate of either ABCB1 or ABCG2. We discovered that, in a concentration-dependent manner, hydroxygenkwanin significantly reverses ABCG2-mediated resistance to multiple cytotoxic anticancer drugs in ABCG2-overexpressing multidrug-resistant cancer cells. Although it inhibited the drug transport function of ABCG2, it had no significant effect on the protein expression of this transporter in cancer cells. Experimental data showing that hydroxygenkwanin stimulates the ATPase activity of ABCG2, and in silico docking analysis of hydroxygenkwanin binding to the inward-open conformation of human ABCG2, further indicate that hydroxygenkwanin sensitizes ABCG2-overexpressing cancer cells by binding to the substrate-binding pocket of ABCG2 and attenuating the transport function of ABCG2. This study demonstrates the potential use of hydroxygenkwanin as an effective inhibitor of ABCG2 in drug combination therapy trials for patients with tumors expressing higher levels of ABCG2.

P-glycoprotein and cancer: what do we currently know?

Acquired resistance during cancer treatment is unfortunately a frequent event. There are several reasons for this, including the ability of the ATP-binding cassette transporters (ABC transporters), which are integral membrane proteins, to export chemotherapeutic molecules from the interior of the tumor cells. One important member of this family is the protein known as Permeability Glycoprotein (P-Glycoprotein, P-gp or ABCB1). Its clinical relevance relies mainly on the fact that the inhibition of P-gp and other ABC transporters could result in the reversal of the multidrug resistance (MDR) phenotype in some patients. Recently, other roles apart from being a key player in MDR, have emerged for P-gp. Therefore, this review discusses the relationship between P-gp and MDR, in addition to the possible role of this protein as a biomarker in cancer.

New Dual P-Glycoprotein (P-gp) and Human Carbonic Anhydrase XII (hCA XII) Inhibitors as Multidrug Resistance (MDR) Reversers in Cancer Cells

In a continuing search of dual P-gp and hCA XII inhibitors, we synthesized and studied new N,N-bis(alkanol)amine aryl diester derivatives characterized by the presence of a coumarin group. These hybrids contain both P-gp and hCA XII binding groups to synergistically overcome the P-gp-mediated multidrug resistance (MDR) in cancer cells expressing both P-gp and hCA XII. Indeed, hCA XII modulates the efflux activity of P-gp and the inhibition of hCA XII reduces the intracellular pH, thereby decreasing the ATPase activity of P-gp. All compounds showed inhibitory activities on P-gp and hCA XII proteins taken individually, and many of them displayed a synergistic effect in HT29/DOX and A549/DOX cells that overexpress both P-gp and hCA XII, being more potent than in K562/DOX cells overexpressing only P-gp. Compounds 5 and 14 were identified as promising chemosensitizer agents for selective inhibition in MDR cancer cells overexpressing both P-gp and hCA XII.

The WD repeat-containing protein 5 (WDR5) antagonist WDR5-0103 restores the efficacy of cytotoxic drugs in multidrug-resistant cancer cells overexpressing ABCB1 or ABCG2

The development of multidrug resistance (MDR) is one of the major challenges in the treatment of cancer which is caused by the overexpression of the ATP-binding cassette (ABC) transporters ABCB1 (P-glycoprotein) and/or ABCG2 (BCRP/MXR/ABCP) in cancer cells. These transporters are capable of reducing the efficacy of cytotoxic drugs by actively effluxing them out of cancer cells. Since there is currently no approved treatment for patients with multidrug-resistant tumors, the drug repurposing approach provides an alternative route to identify agents to reverse MDR mediated by ABCB1 and/or ABCG2 in multidrug-resistant cancer cells. WDR5-0103 is a histone H3 lysine 4 (H3K4) methyltransferase inhibitor that disrupts the interaction between the WD repeat-containing protein 5 (WDR5) and mixed-lineage leukemia (MLL) protein. In this study, the effect of WDR5-0103 on MDR mediated by ABCB1 and ABCG2 was determined. We found that in a concentration-dependent manner, WDR5-0103 could sensitize ABCB1- and ABCG2-overexpressing multidrug-resistant cancer cells to conventional cytotoxic drugs. Our results showed that WDR5-0103 reverses MDR and improves drug-induced apoptosis in multidrug-resistant cancer cells by inhibiting the drug-efflux function of ABCB1 and ABCG2, without altering the protein expression of ABCB1 or ABCG2. The potential sites of interactions of WDR5-0103 with the drug-binding pockets of ABCB1 and ABCG2 were predicted by molecular docking. In conclusion, the MDR reversal activity of WDR5-0103 demonstrated here indicates that it could be used in combination therapy to provide benefits to a subset of patients with tumor expressing high levels of ABCB1 or ABCG2.

Applications of Nanotechnology-based Approaches to Overcome Multi-drug Resistance in Cancer

Cancer is one of the leading causes of death worldwide. Chemotherapy and radiation therapy are the major treatments used for the management of cancer. Multidrug resistance (MDR) is a major hindrance faced in the treatment of cancer and is also responsible for cancer relapse. To date, several studies have been carried out on strategies to overcome or reverse MDR in cancer. Unfortunately, the MDR reversing agents have been proven to have minimal clinical benefits, and eventually, no improvement has been made in therapeutic efficacy to date. Thus, several investigational studies have also focused on overcoming drug resistance rather than reversing the MDR. In this review, we focus primarily on nanoformulations regarded as a novel approach to overcome or bypass the MDR in cancer. The nanoformulation systems serve as an attractive strategy as these nanosized materials selectively get accumulated in tumor tissues, thereby improving the clinical outcomes of patients suffering from MDR cancer. In the current work, we present an overview of recent trends in the application of various nano-formulations, belonging to different mechanistic classes and functionalization like carbon nanotubes, carbon nanohorns, carbon nanospheres, liposomes, dendrimers, etc., to overcome MDR in cancer. A detailed overview of these techniques will help researchers in exploring the applicability of nanotechnologybased approaches to treat MDR.

LC-MS/MS Phytochemical Profiling, Antioxidant Activity, and Cytotoxicity of the Ethanolic Extract of Atriplex halimus L. against Breast Cancer Cell Lines: Computational Studies and Experimental Validation

Atriplex halimus L., also known as Mediterranean saltbush, and locally as "Lgtef", an halophytic shrub, is used extensively to treat a wide variety of ailments in Morocco. The present study was undertaken to determine the antioxidant activity and cytotoxicity of the ethanolic extract of A. halimus leaves (AHEE). We first determined the phytochemical composition of AHEE using a liquid chromatography (LC)-tandem mass spectrometry (MS/MS) technique. The antioxidant activity was evaluated using different methods including DPPH scavenging capacity, β-carotene bleaching assay, ABTS scavenging, iron chelation, and the total antioxidant capacity assays. Cytotoxicity was investigated against human cancer breast cells lines MCF-7 and MDA-MB-231. The results showed that the components of the extract are composed of phenolic acids and flavonoids. The DPPH test showed strong scavenging capacity for the leaf extract (IC₅₀ of 0.36 ± 0.05 mg/mL) in comparison to ascorbic acid (IC₅₀ of 0.19 ± 0.02 mg/mL). The β-carotene test determined an IC₅₀ of 2.91 ± 0.14 mg/mL. The IC₅₀ values of ABTS, iron chelation, and TAC tests were 44.10 ± 2.92 TE µmol/mL, 27.40 ± 1.46 mg/mL, and 124 ± 1.27 µg AAE/mg, respectively. In vitro, the AHE extract showed significant inhibitory activity in all tested tumor cell lines, and the inhibition activity was found in a dose-dependent manner. Furthermore, computational techniques such as molecular docking and ADMET analysis were used in this work. Moreover, the physicochemical parameters related to the compounds' pharmacokinetic indicators were evaluated, including absorption, distribution, metabolism, excretion, and toxicity prediction (Pro-Tox II).

Effects of Ion-Transporting Proteins on the Digestive System Under Hypoxia

Hypoxia refers to a state of oxygen limitation, which mainly mediates pathological processes in the human body and participates in the regulation of normal physiological processes. In the hypoxic environment, the main regulator of human body homeostasis is the hypoxia-inducible factor family (HIF). HIF can regulate the expression of many hypoxia-induced genes and then participate in various physiological and pathological processes of the human body. Ion-transporting proteins are extremely important types of proteins. Ion-transporting proteins are distributed on cell membranes or organelles and strictly control the inflow or outflow of ions in cells or organelles. Changes in ions in cells are often closely related to extensive physiological and pathological processes in the human body. Numerous studies have confirmed that hypoxia and its regulatory factors can regulate the transcription and expression of ion-transporting protein-related genes. Under hypoxic stress, the regulation and interaction of ion-transporting proteins by hypoxia often leads to diseases of various human systems and even tumors. Using ion-transporting proteins and hypoxia as targets to explore the mechanism of digestive system diseases and targeted therapy is expected to become a new breakthrough point.

Combinatorial approaches of nanotherapeutics for inflammatory pathway targeted therapy of prostate cancer

Prostate cancer (PC) is the most prevalent male urogenital cancer worldwide. PC patients presenting an advanced or metastatic cancer succumb to the disease, even after therapeutic interventions including radiotherapy, surgery, androgen deprivation therapy (ADT), and chemotherapy. One of the hallmarks of PC is evading immune surveillance and chronic inflammation, which is a major challenge towards designing effective therapeutic formulations against PC. Chronic inflammation in PC is often characterized by tumor microenvironment alterations, epithelial-mesenchymal transition and extracellular matrix modifications. The inflammatory events are modulated by reactive nitrogen and oxygen species, inflammatory cytokines and chemokines. Major signaling pathways in PC includes androgen receptor, PI3K and NF-κB pathways and targeting these inter-linked pathways poses a major therapeutic challenge. Notably, many conventional treatments are clinically unsuccessful, due to lack of targetability and poor bioavailability of the therapeutics, untoward toxicity and multidrug resistance. The past decade witnessed an advancement of nanotechnology as an excellent therapeutic paradigm for PC therapy. Modern nanovectorization strategies such as stimuli-responsive and active PC targeting carriers offer controlled release patterns and superior anti-cancer effects. The current review initially describes the classification, inflammatory triggers and major inflammatory pathways of PC, various PC treatment strategies and their limitations. Subsequently, recent advancement in combinatorial nanotherapeutic approaches, which target PC inflammatory pathways, and the mechanism of action are discussed. Besides, the current clinical status and prospects of PC homing nanovectorization, and major challenges to be addressed towards the advancement PC therapy are also addressed.

Combination treatment with hENT1 and miR-143 reverses gemcitabine resistance in triple-negative breast cancer

Background

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer and is susceptible to develop gemcitabine (GEM) resistance. Decreased expression of human equilibrative nucleoside transporter 1 (hENT1) accompanied by compensatory increase of glycolysis is strongly associated with GEM resistance in TNBC. In this study, we investigated the treatment feasibility of combined hENT1 upregulation and miR-143-mediated inhibition of glycolysis for reversing GEM resistance in TNBC.

Methods

Experiments were performed in vitro and in vivo to compare the efficacy of GEM therapies. In this study, we established stable drug-resistant cell line, GEM-R cells, from parental cells (MDA-MB-231) through exposure to GEM following a stepwise incremental dosing strategy. Then GEM-R cells were transfected by lentiviral plasmids and GEM-R cells overexpressing hENT1 (GEM-R-hENT1) were established. The viability and apoptosis of wild-type (MDA-MB-231), GEM-R, and GEM-R-hENT1 cells treated with GEM or GEM + miR-143 were analyzed by CCK8 assay and flow cytometry. The RNA expression and protein expression were measured by RT-PCR and western blotting respectively. GEM uptake was determined by multiple reaction monitoring (MRM) analysis. Glycolysis was measured by glucose assay and ¹⁸F-FDG uptake. The antitumor effect was assessed in vivo in a tumor xenograft model by evaluating toxicity, tumor volume, and maximum standardized uptake value in ¹⁸F-FDG PET. Immunohistochemistry and fluorescence photography were taken in tumor samples. Pairwise comparisons were performed using Student’s t-test.

Results

Our results represented that overexpression of hENT1 reversed GEM resistance in GEM-R cells by showing lower IC₅₀ and higher rate of apoptosis. MiR-143 suppressed glycolysis in GEM-R cells and enhanced the effect of reversing GEM resistance in GEM-R-hENT1 cells. The therapeutic efficacy was validated using a xenograft mouse model. Combination treatment decreased tumor growth rate and maximum standardized uptake value in ¹⁸F-FDG PET more effectively.

Conclusions

Combined therapy of exogenous upregulation of hENT1 expression and miR-143 mimic administration was effective in reversing GEM resistance, providing a promising strategy for treating GEM-resistant TNBC.

Alteration of Manure Antibiotic Resistance Genes via Soil Fauna Is Associated with the Intestinal Microbiome

Livestock wastes contain high levels of antibiotic resistance genes (ARGs) and a variety of human-related pathogens. Bioconversion of livestock manure using larvae of the beetle Protaetia brevitarsis is an effective technique for waste reduction and value creation; however, the fate of manure ARGs during gut passage and interaction with the gut microbiome of P. brevitarsis remains unclear. To investigate this, we fed P. brevitarsis with dry chicken manure for 6 days and measured bacterial community dynamics and ARG abundance and diversity along the P. brevitarsis gut tract using high-throughput quantitative PCR and metagenomics approaches. The diversity of ARGs was significantly lower in larval midgut, hindgut, and frass than in raw chicken manure, and around 80% of pathogenicity-related genes (PRGs) exhibited reduced abundance. Network analysis demonstrated that Bacteroidetes and Firmicutes were the key bacterial phyla associated with ARG reduction. Metagenomic analysis further indicated that ARGs, mobile genetic elements (MGEs), and PRGs were simultaneously attenuated in the hindgut, implicating a decreased likelihood for horizontal gene transfer (HGT) of ARGs among bacteria and pathogens during manure bioconversion. Our findings demonstrated that the attenuation of ARGs is strongly associated with the variation of the gut microbiome of P. brevitarsis, providing insights into mechanisms of risk mitigation of ARG dissemination during manure bioconversion. IMPORTANCE Saprophagous fauna like the oriental edible beetle (P. brevitarsis) plays a fundamental role in converting organic wastes into biofertilizer. Accumulating evidence has shown that soil fauna can reduce the abundance of ARGs, although the underlying mechanism of ARG reduction is still unclear. In our previous research, we found a large reduction of ARGs in vegetable roots and leaves from frass compared with raw manure, providing a promising biofertilizer for soil-vegetable systems. Therefore, in this study, temporal dynamic changes in the microbiomes of the donor (chicken manure) and host (P. brevitarsis) were investigated, and we found a close association between the gut microbiome and the alteration of ARGs. These results shed new light on how the insect gut microbiome can mitigate manure-borne ARGs and provide insights into the bioconversion process via a typical member of the saprophagous fauna, P. brevitarsis.

Isocitrate dehydrogenase 2 inhibitor enasidenib synergizes daunorubicin cytotoxicity by targeting aldo-keto reductase 1C3 and ATP-binding cassette transporters

Targeting mutations that trigger acute myeloid leukaemia (AML) has emerged as a refined therapeutic approach in recent years. Enasidenib (Idhifa) is the first selective inhibitor of mutated forms of isocitrate dehydrogenase 2 (IDH2) approved against relapsed/refractory AML. In addition to its use as monotherapy, a combination trial of enasidenib with standard intensive induction therapy (daunorubicin + cytarabine) is being evaluated. This study aimed to decipher enasidenib off-target molecular mechanisms involved in anthracycline resistance, such as reduction by carbonyl reducing enzymes (CREs) and drug efflux by ATP-binding cassette (ABC) transporters. We analysed the effect of enasidenib on daunorubicin (Daun) reduction by several recombinant CREs and different human cell lines expressing aldo-keto reductase 1C3 (AKR1C3) exogenously (HCT116) or endogenously (A549 and KG1a). Additionally, A431 cell models overexpressing ABCB1, ABCG2, or ABCC1 were employed to evaluate enasidenib modulation of Daun efflux. Furthermore, the potential synergism of enasidenib over Daun cytotoxicity was quantified amongst all the cell models. Enasidenib selectively inhibited AKR1C3-mediated inactivation of Daun in vitro and in cell lines expressing AKR1C3, as well as its extrusion by ABCB1, ABCG2, and ABCC1 transporters, thus synergizing Daun cytotoxicity to overcome resistance. This work provides in vitro evidence on enasidenib-mediated targeting of the anthracycline resistance actors AKR1C3 and ABC transporters under clinically achievable concentrations. Our findings may encourage its combination with intensive chemotherapy and even suggest that the effectiveness of enasidenib as monotherapy against AML could lie beyond the targeting of mIDH2.

siRNA-based nanotherapeutics as emerging modalities for immune-mediated diseases: A preliminary review

Immune‐mediated diseases (IMDs) are chronic conditions that have an immune‐mediated etiology. Clinically, these diseases appear to be unrelated, but pathogenic pathways have been shown to connect them. While inflammation is a common occurrence in the body, it may either stimulate a favorable immune response to protect against harmful signals or cause illness by damaging cells and tissues. Nanomedicine has tremendous promise for regulating inflammation and treating IMIDs. Various nanoparticles coated with nanotherapeutics have been recently fabricated for effective targeted delivery to inflammatory tissues. RNA interference (RNAi) offers a tremendous genetic approach, particularly if traditional treatments are ineffective against IMDs. In cells, several signaling pathways can be suppressed by using RNAi, which blocks the expression of particular messenger RNAs. Using this molecular approach, the undesirable effects of anti‐inflammatory medications can be reduced. Still, there are many problems with using short‐interfering RNAs (siRNAs) to treat IMDs, including poor localization of the siRNAs in target tissues, unstable gene expression, and quick removal from the blood. Nanotherapeutics have been widely used in designing siRNA‐based carriers because of the restricted therapy options for IMIDs. In this review, we have discussed recent trends in the fabrication of siRNA nanodelivery systems, including lipid‐based siRNA nanocarriers, liposomes, and cationic lipids, stable nucleic acid‐lipid particles, polymeric‐based siRNA nanocarriers, polyethylenimine (PEI)‐based nanosystems, chitosan‐based nanoformulations, inorganic material‐based siRNA nanocarriers, and hybrid‐based delivery systems. We have also introduced novel siRNA‐based nanocarriers to control IMIDs, such as pulmonary inflammation, psoriasis, inflammatory bowel disease, ulcerative colitis, rheumatoid arthritis, etc. This study will pave the way for new avenues of research into the diagnosis and treatment of IMDs.

Mechanisms of chemotherapy resistance in ovarian cancer

Ovarian cancer is one of the most lethal gynecologic cancers. The standard therapy for ovarian cancer has been the same for the past two decades, a combination treatment of platinum with paclitaxel. Recently, the FDA approved three new therapeutic drugs, two poly (ADP-ribose) polymerase inhibitors (olaparib and niraparib) and one vascular endothelial growth factor inhibitor (bevacizumab) as maintenance therapies for ovarian cancer. In this review, we summarize the resistance mechanisms for conventional platinum-based chemotherapy and for the newly FDA-approved drugs.

Doxorubicin-conjugated siRNA lipid nanoparticles for combination cancer therapy

Evasion of apoptosis is a hallmark of cancer, attributed in part to overexpression of the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2). In a variety of cancer types, including lymphoma, Bcl-2 is overexpressed. Therapeutic targeting of Bcl-2 has demonstrated efficacy in the clinic and is the subject of extensive clinical testing in combination with chemotherapy. Therefore, the development of co-delivery systems for Bcl-2 targeting agents, such as small interfering RNA (siRNA), and chemotherapeutics, such as doxorubicin (DOX), holds promise for enabling combination cancer therapies. Lipid nanoparticles (LNPs) are a clinically advanced nucleic acid delivery system with a compact structure suitable for siRNA encapsulation and delivery. Inspired by ongoing clinical trials of albumin-hitchhiking doxorubicin prodrugs, here we developed a DOX-siRNA co-delivery strategy via conjugation of doxorubicin to the surface of siRNA-loaded LNPs. Our optimized LNPs enabled potent knockdown of Bcl-2 and efficient delivery of DOX into the nucleus of Burkitts' lymphoma (Raji) cells, leading to effective inhibition of tumor growth in a mouse model of lymphoma. Based on these results, our LNPs may provide a platform for the co-delivery of various nucleic acids and DOX for the development of new combination cancer therapies.

Platelets for cancer treatment and drug delivery

Extensive research is currently being conducted into a variety of bio-inspired biomimetic nanoparticles (NPs) with new cell simulation functions across the fields of materials science, chemistry, biology, physics, and engineering. Cells such as erythrocytes, platelets, and stem cells have been engineered as new drug carriers. The platelet-derived drug delivery system, which is a new targeted drug delivery system (TDDS), can effectively navigate the blood circulatory system and interact with the complex tumor microenvironment; it appears to outperform traditional anticancer drugs; hence, it has attracted considerable research interest. In this review, we describe innovative studies and outline the latest progress regarding the use of platelets as tumor targeting and drug delivery vehicles; we also highlight opportunities and challenges relevant to the manufacture of tumor-related platelet TDDSs.

CRISPR/Cas9 gene editing: a new approach for overcoming drug resistance in cancer

The CRISPR/Cas9 system is an RNA-based adaptive immune system in bacteria and archaea. Various studies have shown that it is possible to target a wide range of human genes and treat some human diseases, including cancers, by the CRISPR/Cas9 system. In fact, CRISPR/Cas9 gene editing is one of the most efficient genome manipulation techniques. Studies have shown that CRISPR/Cas9 technology, in addition to having the potential to be used as a new therapeutic approach in the treatment of cancers, can also be used to enhance the effectiveness of existing treatments. Undoubtedly, the issue of drug resistance is one of the main obstacles in the treatment of cancers. Cancer cells resist anticancer drugs by a variety of mechanisms, such as enhancing anticancer drugs efflux, enhancing DNA repair, enhancing stemness, and attenuating apoptosis. Mutations in some proteins of different cellular signaling pathways are associated with these events and drug resistance. Recent studies have shown that the CRISPR/Cas9 technique can be used to target important genes involved in these mechanisms, thereby increasing the effectiveness of anticancer drugs. In this review article, studies related to the applications of this technique in overcoming drug resistance in cancer cells will be reviewed. In addition, we will give a brief overview of the limitations of the CRISP/Cas9 gene-editing technique.

P-glycoprotein Mediates Resistance to the Anaplastic Lymphoma Kinase Inhiitor Ensartinib in Cancer Cells

Ensartinib (X-396) is a promising second-generation small-molecule inhibitor of anaplastic lymphoma kinase (ALK) that was developed for the treatment of ALK-positive non-small-cell lung cancer. Preclinical and clinical trial results for ensartinib showed superior efficacy and a favorable safety profile compared to the first-generation ALK inhibitors that have been approved by the U.S. Food and Drug Administration. Although the potential mechanisms of acquired resistance to ensartinib have not been reported, the inevitable emergence of resistance to ensartinib may limit its therapeutic application in cancer. In this work, we investigated the interaction of ensartinib with P-glycoprotein (P-gp) and ABCG2, two ATP-binding cassette (ABC) multidrug efflux transporters that are commonly associated with the development of multidrug resistance in cancer cells. Our results revealed that P-gp overexpression, but not expression of ABCG2, was associated with reduced cancer cell susceptibility to ensartinib. P-gp directly decreased the intracellular accumulation of ensartinib, and consequently reduced apoptosis and cytotoxicity induced by this drug. The cytotoxicity of ensartinib could be significantly reversed by treatment with the P-gp inhibitor tariquidar. In conclusion, we report that ensartinib is a substrate of P-gp, and provide evidence that this transporter plays a role in the development of ensartinib resistance. Further investigation is needed.

Advances in Hydrogel-Based Microfluidic Blood–Brain-Barrier Models in Oncology Research

The intrinsic architecture and complexity of the brain restricts the capacity of therapeutic molecules to reach their potential targets, thereby limiting therapeutic possibilities concerning neurological ailments and brain malignancy. As conventional models fail to recapitulate the complexity of the brain, progress in the field of microfluidics has facilitated the development of advanced in vitro platforms that could imitate the in vivo microenvironments and pathological features of the blood–brain barrier (BBB). It is highly desirous that developed in vitro BBB-on-chip models serve as a platform to investigate cancer metastasis of the brain along with the possibility of efficiently screening chemotherapeutic agents against brain malignancies. In order to improve the proficiency of BBB-on-chip models, hydrogels have been widely explored due to their unique physical and chemical properties, which mimic the three-dimensional (3D) micro architecture of tissues. Hydrogel-based BBB-on-chip models serves as a stage which is conducive for cell growth and allows the exchange of gases and nutrients and the removal of metabolic wastes between cells and the cell/extra cellular matrix (ECM) interface. Here, we present recent advancements in BBB-on-chip models targeting brain malignancies and examine the utility of hydrogel-based BBB models that could further strengthen the future application of microfluidic devices in oncology research.