Thermodynamic stability of cisplatin-loaded polymeric micelles and the phenotypic switching of the tumor-associated macrophages induced by combination of cisplatin-loaded micelles and Anti-PD-L1 antibody

Platinum-based chemotherapy: trends in organic nanodelivery systems

Despite the investment in platinum drugs research, cisplatin, carboplatin and oxaliplatin are still the only Pt-based compounds used as first line treatments for several cancers, with a few other compounds being approved for administration in some Asian countries. However, due to the severe and worldwide impact of oncological diseases, there is an urge for improved chemotherapeutic approaches. Furthermore, the pharmaceutical application of platinum complexes is hindered by their inherent toxicity and acquired resistance. Nanodelivery systems rose as a key strategy to overcome these challenges, with recognized versatility and ability towards improving the safety, bioavailability and efficacy of the available drugs. Among the known nanocarriers, organic systems have been widely applied, taking advantage of their potential as drug vehicles. Researchers have mainly focused on the development of lipidic and polymeric carriers, including supramolecular structures, with an overall improvement of encapsulated platinum complexes. Herein, an overview of recent trends and strategies is presented, with the main focus on the encapsulation of platinum compounds into organic nanocarriers, showcasing the evolution in the design and development of these promising systems. This comprehensive review highlights formulation methods as well as characterization procedures, providing insights that may be helpful for the development of novel platinum nanocarriers aiming at future pharmaceutical applications.

Unlocking apoptosis in triple negative breast cancer: Harnessing "glutamine trap" to amplify the efficacy of lapatinib-loaded mixed micelles

Certain aggressive cancers, such as triple-negative breast cancer (TNBC), heavily bank on glutamine for their proliferation and survival. In this context, TNBC functions as a "glutamine trap," extracting circulating glutamine at a rate surpassing that of any other organ. Moreover, the overexpression of Alanine, Serine, Cysteine Transporter 2 (ASCT2), a key player in glutamine uptake, further underscores the significance of targeted therapy to enhance TNBC treatment. This led to the exploration of a novel approach involving hydrophobized Pluronic-based mixed micelles achieved through the use of docosahexaenoic acid and stapled with glutamine for displaying inherent ASCT2 targeting ability-a formulation termed LPT G-MM. LPT G-MM exhibited optimal characteristics, including a size of 163.66 ± 10.34 nm, a polydispersity index of 0.237 ± 0.083, and an enhanced drug loading capacity of approximately 15 %. Transmission electron microscopy validated the spherical shape of these micelles. In vitro release studies demonstrated drug release in a sustained manner without the risk of hemolysis. Importantly, LPT G-MM displayed heightened cellular uptake, increased cytotoxicity, a lower IC50 value, elevated reactive oxygen species, induced mitochondrial membrane depolarization, and a greater apoptosis index in TNBC cell lines compared to free LPT. The pharmacokinetic profile of LPT G-MM revealed a substantial rise in half-life (t1/2) by approximately 1.48-fold and an elevation in the area under the curve [AUC(0→∞)] by approximately 1.19-fold. Moreover, there was a significant reduction in the percentage of tumor volume by approximately 7.26-fold, along with decreased serum toxicity markers compared to free LPT. In summary, LPT G-MM demonstrated promising potential in boosting payload capacities and targeting specificity in the context of TNBC treatment.

Design of carboxymethylcellulose-conjugated polymeric prodrug micelles for enhanced in vivo performance of docetaxel

Docetaxel (DTX) has become one of the most important cytotoxic drugs to treat cancer; nevertheless, its poor hydrophilicity and non-specific distribution of DTX lead to detrimental side effects. In this article, we devised carboxymethylcellulose (CMC)-conjugated polymeric prodrug micelles (mPEG-CMC-DTX PMs) for DTX delivery. The ester-bonded polymeric prodrug, mPEG-CMC-DTX, was synthesized and exhibited the capacity for self-assembling into polymeric micelles. The CMC is profusely substituted and acetylated to promote the coupling rate of DTX. Covalent binding of DTX and CMC through an ester bond can be hydrolyzed to dissociate the bond under the action of esterase in the tumor. The mPEG-CMC-DTX PMs displayed promoted drug loading (>50 %, wt), commendable stability, and sustained release behavior in vitro. The gradual release of the prodrug amplified the selectivity of cytotoxicity between normal cells and tumor cells, mitigating the systemic toxicity of mPEG-CMC-DTX PMs and enabling dose intensification. Notably, mPEG-CMC-DTX PMs demonstrated a superior antitumor efficacy and low systemic toxicity due to the elevated tolerance dosage (even at 40 mg/kg DTX). In summation, mPEG-CMC-DTX PMs harmonized the antitumor efficacy and toxicity of DTX. In essence, innovative perspectives for the rational design of CMC-conjugated polymeric prodrug micelles for the delivery of potently toxic drugs were proffered.

Recent Advances in Nanomaterials-Based Targeted Drug Delivery for Preclinical Cancer Diagnosis and Therapeutics

Nano-oncology is a branch of biomedical research and engineering that focuses on using nanotechnology in cancer diagnosis and treatment. Nanomaterials are extensively employed in the field of oncology because of their minute size and ultra-specificity. A wide range of nanocarriers, such as dendrimers, micelles, PEGylated liposomes, and polymeric nanoparticles are used to facilitate the efficient transport of anti-cancer drugs at the target tumor site. Real-time labeling and monitoring of cancer cells using quantum dots is essential for determining the level of therapy needed for treatment. The drug is targeted to the tumor site either by passive or active means. Passive targeting makes use of the tumor microenvironment and enhanced permeability and retention effect, while active targeting involves the use of ligand-coated nanoparticles. Nanotechnology is being used to diagnose the early stage of cancer by detecting cancer-specific biomarkers using tumor imaging. The implication of nanotechnology in cancer therapy employs photoinduced nanosensitizers, reverse multidrug resistance, and enabling efficient delivery of CRISPR/Cas9 and RNA molecules for therapeutic applications. However, despite recent advancements in nano-oncology, there is a need to delve deeper into the domain of designing and applying nanoparticles for improved cancer diagnostics.

SPLUNC1 regulates LPS-induced progression of nasopharyngeal carcinoma and proliferation of myeloid-derived suppressor cells

Nasopharyngeal carcinoma (NPC) is one of the aggressive malignant tumors with high mortality, and the proliferation of myeloid-derived suppressor cells (MDSCs) could promote the metastasis of NPC through inhibiting the function of T cells. Meanwhile, SPLUNC1 was known to inhibit the malignant behavior of NPC cells, while the detailed function of SPLUNC1 in LPS-modified immune microenvironment of NPC remains unclear. To assess the impact of SPLUNC1 in immune microenvironment during the progression of NPC, NPC cells were exposed to LPS and then co-cultured with MDSCs for 48 h. RT-qPCR and western blot were performed to evaluate the mRNA and protein level of SPLUNC1, CXCL-2 and CXCR-2, respectively. The level of IL-1β, IL-6, TNF-α, PD-L1, Arg-1 and iNOS were tested by ELISA. Meanwhile, the expression of CD33⁺ was tested by flow cytometry. The expression of CXCL-2 and CXCR-2 in NPC cells was higher, compared to that in NP69 cells. In contrast, SPLUNC1 level in NPC cells was much lower than that in NP69 cells. SPLUNC1 level was negatively correlated with CXCL-2 and CXCR-2. Overexpression of SPLUNC1 reversed LPS-induced inflammatory responses and proliferation in NPC cells. In addition, SPLUNC1 upregulation could reverse LPS-induced proliferation of MDSCs in tumor microenvironment. Meanwhile, SPLUNC1 overexpression could regulate CXCL-2/CXCR-2 axis through decreasing CXCL-2 and CXCR-2 protein and mRNA expression. SPLUNC1 regulates LPS-induced progression of nasopharyngeal carcinoma and proliferation of MDSCs. Thus, our study might provide a theoretical basis for discovering new strategies against NPC.