Effect of Cellular and Microenvironmental Multidrug Resistance on Tumor-Targeted Drug Delivery in Triple-Negative Breast cancer

Targeted NIR-triggered doxorubicin release using carbon dots-poly(ethylene glycol)-folate conjugates for breast cancer treatment

Carbon dot (CD)-based theranostics offers a promising approach for breast cancer (BC) treatment, integrating ultra-localized chemo-photothermal effects to address chemoresistance and enhance therapeutic control. Herein, the development of a targeted theranostic nanosystem for the chemo-phototherapy of breast cancer is described. Fluorescent and biocompatible CDs were passivated with 1,2-bis(3-aminopropylamino)ethane (bAPAE) and decorated with the targeting agent folic acid (FA) through conjugation with a PEG spacer. This yielded CDs-bAPAE-PEG-FA, hydrophilic nanocarriers (12 nm) with a high drug interaction surface. Fluorescence analysis confirmed their utility as bioimaging probes, while NIR light stimulation demonstrated good photothermal conversion. Doxorubicin-loaded CDs (CDs-bAPAE-PEG-FA/Dox) showed an on-demand NIR-boosted drug release, increased by 50% after localized NIR exposure, while in vitro studies on BC cells MCF-7 and MDA-MB-231 demonstrated NIR-enhanced antitumor efficacy, providing the opportunity to realize selective and remote-controlled synergistic therapy. Furthermore, uptake investigations highlighted the imaging potential of CDs and efficient internalization of doxorubicin, emphasizing FA's role in receptor-mediated specific targeting. Data suggest that CDs-bAPAE-PEG-FA/Dox could perform efficient image-guided and selective BC therapy, enhancing the therapeutic outcomes.

Fluorescent Polymer Nanocomposites as Novel Drug-Loading and Targeted Delivery Nanocarriers for Glioma Therapy by Modulating ERBB4

Gliomas are the most common type of tumor in the human central nervous system, characterized by high aggressiveness, elevated mortality, and poor prognosis. Therefore, developing new therapeutic strategies is crucial for improving glioma treatment. Temozolomide (TMZ) is widely used in glioma therapy due to its excellent ability to penetrate the blood-brain barrier. In this study, we synthesized HA-PEG@ICG using hyaluronic acid (HA) and polyethylene glycol (PEG), modified with the fluorescent compound indocyanine green (ICG), and thoroughly characterized the product's structure. Subsequently, compound 1 and TMZ were co-loaded onto this carrier to construct a synergistic drug delivery system (HA-PEG@ICG@1@TMZ). Additionally, we evaluated the inhibitory effects and mechanisms of HA-PEG@ICG@1@TMZ on glioma cell proliferation. Our study lays the foundation for further exploration of TMZ-based therapies for glioma treatment.

Targeting miR-21 to Overcome P-glycoprotein Drug Efflux in Doxorubicin-Resistant 4T1 Breast Cancer

Acquired resistance to chemotherapy is a major challenge in the treatment of triple-negative breast cancer (TNBC). Despite accumulated evidence showing microRNA-21 (miR-21) as a vital regulator of tumor progression, the role of miR-21 in modulating the multidrug resistance of TNBC remains obscure. In this study, we demonstrate that miR-21 affects chemoresistance in 4T1 TNBC cells in response to doxorubicin (DOX) by regulating the P-glycoprotein (P-gp) drug efflux pump. Overexpression of miR-21 in the 4T1 cells markedly reduced their sensitivity to DOX, impeding DOX-promoted cell death. We employed anti-miR-21 oligonucleotide conjugated with a PD-L1-binding peptide (P21) for targeted delivery to 4T1 tumor cells. The selective down-regulation of miR-21 in 4T1 TNBC led to the reversal of P-gp-mediated DOX resistance by up-regulating phosphatase and tensin homolog (PTEN). Our study highlights that miR-21 is a key regulator of drug efflux pumps in TNBC, and targeting miR-21 could enhance DOX sensitivity, offering a potential therapeutic option for patients with DOX-resistant TNBC.

Enhanced antitumor activity of lapatinib against triple-negative breast cancer via loading in human serum albumin

Triple-negative breast cancer (TNBC) presents significant treatment challenges due to its aggressive nature. Human serum albumin (HSA) is a promising drug delivery platform, offering high binding capacity, biocompatibility, and reduced toxicity. Lapatinib (LAP), a tyrosine kinase inhibitor for TNBC, is hindered by poor water solubility and toxicity. To address these issues, LAP was encapsulated within HSA (HSA-LAP), and its structural, drug release, and therapeutic properties were evaluated in cellular and animal TNBC models. HSA-LAP demonstrated efficient drug loading and pH-dependent tumor-targeted release, favoring acidic tumor microenvironments. Structural and microscopic studies confirmed LAP binding to HSA, with only minor structural and no significant morphological changes observed. In 4T1 breast cancer cells, HSA-LAP exhibited superior anti-proliferative, pro-apoptotic, and anti-migratory effects compared to free LAP, which were further amplified when combined with VGB3, a VEGFR1/2-targeting peptide, indicating an effective dual-targeting strategy for TNBC. In vivo, HSA-LAP showed greater tumor inhibition and improved survival rates, especially in combination with VGB3 through apoptosis induction. Biodistribution studies using technetium-99m (99mTc) labeling revealed enhanced tumor targeting. These findings highlight the potential of HSA as a delivery vehicle for LAP, particularly in combination with anti-angiogenic agents like VGB3, offering a promising therapeutic strategy for TNBC.

Enhancing cancer immunotherapy: Nanotechnology-mediated immunotherapy overcoming immunosuppression

Immunotherapy is an important cancer treatment method that offers hope for curing cancer patients. While immunotherapy has achieved initial success, a major obstacle to its widespread adoption is the inability to benefit the majority of patients. The success or failure of immunotherapy is closely linked to the tumor's immune microenvironment. Recently, there has been significant attention on strategies to regulate the tumor immune microenvironment in order to stimulate anti-tumor immune responses in cancer immunotherapy. The distinctive physical properties and design flexibility of nanomedicines have been extensively utilized to target immune cells (including tumor-associated macrophages (TAMs), T cells, myeloid-derived suppressor cells (MDSCs), and tumor-associated fibroblasts (TAFs)), offering promising advancements in cancer immunotherapy. In this article, we have reviewed treatment strategies aimed at targeting various immune cells to regulate the tumor immune microenvironment. The focus is on cancer immunotherapy models that are based on nanomedicines, with the goal of inducing or enhancing anti-tumor immune responses to improve immunotherapy. It is worth noting that combining cancer immunotherapy with other treatments, such as chemotherapy, radiotherapy, and photodynamic therapy, can maximize the therapeutic effects. Finally, we have identified the challenges that nanotechnology-mediated immunotherapy needs to overcome in order to design more effective nanosystems.

Next-generation biomarkers for prognostic and potential therapeutic enhancement in Triple negative breast cancer

Triple-negative breast carcinoma (TNBC) is one of the most challenging subtypes of breast carcinoma and it has very limited therapeutic options as it is highly aggressive. The prognostic biomarkers are crucial for early diagnosis of the tumor, it also helps in anticipating the trajectory of the illness and optimizing the therapy options. Several therapeutic biomarkers are being used. Among them, the next-generation biomarkers that include Circulating tumor (ct) DNA, glycogen, lipid, and exosome biomarkers provide intriguing opportunities for enhancing the prognosis of TNBC. Lipid and glycogen biomarkers serve as essential details on the development of the tumor along with the efficacy of the treatment, as it exhibits metabolic alteration linked to TNBC. Several types of biomarkers have predictive abilities in TNBC. Elevated levels are associated with worse outcomes. ctDNA being a noninvasive biomarker reveals the genetic composition of the tumor, as well as helps to monitor the progression of the disease. Traditional therapies are ineffective in TNBC due to a lack of receptors, targeted drug delivery provides a tailored approach to overcome drug resistance and site-specific action by minimizing the side effects in TNBC treatment. This enhances therapeutic outcomes against the aggressive nature of breast cancer. This paper includes all the recent biomarkers which has been researched so far in TNBC and the state of art for TNBC which is explored.

Nanoemulsion based lipid nanoparticles for effective demethylcantharidin delivery to cure liver cancer

Demethylcantharidin (DEM) is a widely used antitumor drug; however, its poor tumor targeting and serious organotoxicity limit its application. The aim of this study was to develop a new drug delivery system for efficient delivery of DEM. Nanoemulsion based lipid nanoparticles containing demethylcantharidin (DNLNs) were prepared by loading nanoemulsions into lipid nanoparticles. The cells proliferation, apoptosis, cycle, and uptake were investigated by Cell counting kit-8 (CCK-8), flow cytometry, and in situ fluorescence assays, respectively. Then, we established the H22 tumor-bearing mouse model to evaluate the antitumor efficacy of DNLNs and further studied its organ toxicity and distribution. DNLNs significantly inhibited the proliferation and promoted apoptosis of H22 cells, and H22 cells could take up more DNLNs. Compared with DEM, DNLNs had certain tumor-targeting properties, and the tumor inhibition rate increased by 23.24%. Moreover, DNLNs can increase white blood cell count and reduce organ toxicity. This study paves the way for nanoemulsion-based lipid nanoparticle (NLNs)-efficient DEM delivery to treat liver cancer.

A Targeted and Responsive Nanoprodrug Delivery System for Synergistic Glioma Chemotherapy

Doxorubicin (DOX) is widely used as a chemotherapeutic agent for both hematologic and solid tumors and is a reasonable candidate for glioma treatment. However, its effectiveness is hindered by significant toxicity and drug resistance. Moreover, the presence of the blood-brain barrier (BBB) brings a crucial challenge to glioma therapy. In response, a GSH-responsive and actively targeted nanoprodrug delivery system (cRGD/PSDOX-Cur@NPs) are developed. In this system, a disulfide bond-bridged DOX prodrug (PEG-SS-DOX) is designed to release specifically in the high glutathione (GSH) tumor environment, markedly reducing the cardiotoxicity associated with DOX. To further address DOX resistance, curcumin, serving as a P-glycoprotein (P-gp) inhibitor, effectively increased cellular DOX concentration. Consequently, cRGD/PSDOX-Cur@NPs exhibited synergistic anti-tumor effects in vitro. Furthermore, in vivo experiments validated the superior BBB penetration and brain-targeting abilities of cRGD/PSDOX-Cur@NPs, showcasing the remarkable potential for treating both subcutaneous and orthotopic gliomas. This research underscores that this nanoprodrug delivery system presents a novel approach to inhibiting glioma while addressing resistance and systemic toxicity.

Brucea javanica derived exosome-like nanovesicles deliver miRNAs for cancer therapy

Triple-negative breast cancer (TNBC) is characterized by complex heterogeneity, high recurrence and metastasis rates, and short overall survival, owing to the lack of endocrine and targeted receptors, which necessitates chemotherapy as the major treatment regimen. Exosome-like nanovesicles derived from medicinal plants have shown great potential as novel biotherapeutics for cancer therapy by delivering their incorporated nucleic acids, especially microRNAs (miRNAs), to mammalian cells. In this study, we isolated exosome-like nanovesicles derived from B. javanica (BF-Exos) and investigated their influence and underlying molecular mechanisms in TNBC. We found that BF-Exos delivered 10 functional miRNAs to 4T1 cells, significantly retarding the growth and metastasis of 4T1 cells by regulating the PI3K/Akt/mTOR signaling pathway and promoting ROS/caspase-mediated apoptosis. Moreover, BF-Exos were shown to inhibit the secretion of vascular endothelial growth factor, contributing to anti-angiogenesis in the tumor microenvironment. In vivo, BF-Exos inhibited tumor growth, metastasis, and angiogenesis in breast tumor mouse models, while maintaining high biosafety. Overall, BF-Exos are considered promising nanoplatforms for the delivery of medicinal plant-derived nucleic acids, with great potential to be developed into novel biotherapeutics for the treatment of TNBC.

Three-pronged attacks by hybrid nanoassemblies involving a natural product, carbon dots, and Cu2+ for synergistic HCC therapy

Tumor microenvironment (TME) stimuli-responsive nanoassemblies are emerging as promising drug delivery systems (DDSs), which acquire controlled release by structural transformation under exogenous stimulation. However, the design of smart stimuli-responsive nanoplatforms integrated with nanomaterials to achieve complete tumor ablation remains challenging. Therefore, it is of utmost importance to develop TME-based stimuli-responsive DDSs to enhance drug-targeted delivery and release at tumor sites. Herein, we proposed an appealing strategy to construct fluorescence-mediated TME stimulus-responsive nanoplatforms for synergistic cancer therapy by assembling photosensitizers (PSs) carbon dots (CDs), chemotherapeutic agent ursolic acid (UA), and copper ions (Cu2+). First, UA nanoparticles (UA NPs) were prepared by self-assembly of UA, then UA NPs were assembled with CDs via hydrogen bonding force to obtain UC NPs. After combining with Cu2+, the resulting particles (named UCCu2+ NPs) exhibited quenched fluorescence and photosensitization due to the aggregation of UC NPs. Upon entering the tumor tissue, the photodynamic therapy (PDT) and the fluorescence function of UCCu2+ were recovered in response to TME stimulation. The introduction of Cu2+ triggered the charge reversal of UCCu2+ NPs, thereby promoting lysosomal escape. Furthermore, Cu2+ resulted in additional chemodynamic therapy (CDT) capacity by reacting with hydrogen peroxide (H2O2) as well as by consuming glutathione (GSH) in cancer cells through a redox reaction, hence magnifying intracellular oxidative stress and enhancing the therapeutic efficacy due to reactive oxygen species (ROS) therapy. In summary, UCCu2+ NPs provided an unprecedented novel approach for improving the therapeutic efficacy through the three-pronged (chemotherapy, phototherapy, and heat-reinforced CDT) attacks to achieve synergistic therapy.

Overcoming drug resistance with a docetaxel and disulfiram loaded pH-sensitive nanoparticle

Previous studies have demonstrated that breast cancer cells deploy a myriad array of strategies to thwart the activity of anticancer drugs like docetaxel (DTX), including acquired drug resistance due to overexpression of drug-efflux pumps like P-glycoprotein (P-gp) and innate drug resistance by cancer stem cells (CSCs). As disulfiram (DSF) can inhibit both P-gp and CSCs, we hypothesized that co-treatment of DTX and DSF could sensitize the drug-resistant breast cancer cells. To deliver a fixed dose ratio of DTX and DSF targeted to the tumor, a tumor extracellular pH-responsive nanoparticle (NP) was developed using a histidine-conjugated star-shaped PLGA with TPGS surface decoration ([DD]NpH-T). By releasing the encapsulated drugs in the tumor microenvironment, pH-sensitive NPs can overcome the tumor stroma-based resistance against nanomedicines. In in-vitro studies, [DD]NpH-T exhibited increased drug release at pH 6.8, improved penetration in a 3D tumor spheroid, reduced serum protein adsorption, and enhanced cytotoxic efficacy against both innate and acquired DTX-resistant breast cancer cells. In in-vivo studies, a significant increase in plasma AUC and tumor drug delivery was observed with [DD]NpH-T, which resulted in an enhanced in-vivo anti-tumor efficacy against a mouse orthotopic breast cancer, with a significantly increased intratumoral ROS and apoptosis, while decreasing P-gp expression and prevention of lung metastasis. Altogether, the current study demonstrated that the DTX and DSF combination could effectively target multiple drug-resistance pathways in-vitro, and the in-vivo delivery of this drug combination using TPGS-decorated pH-sensitive NPs could increase tumor accumulation, resulting in improved anti-tumor efficacy.