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Platelet extracellular vesicles (PEVs) are an emerging delivery vehi for anticancer drugs due to their ability to target and remain in the tumor microenvironment. However, there is still a lack of understanding regarding yields, safety, drug loading efficiencies, and efficacy of PEVs. In this study, various methods were compared to generate PEVs from clinical-grade platelets, and their properties were examined as vehicles for doxorubicin (DOX). Sonication and extrusion produced the most PEVs, with means of 496 and 493 PEVs per platelet (PLT), respectively, compared to 145 and 33 by freeze/thaw and incubation, respectively. The PEVs were loaded with DOX through incubation and purified by chromatography. The size and concentration of the PEVs and PEV-DOX were analyzed using dynamic light scattering and nanoparticle tracking analysis. The results showed that the population sizes and concentrations of PEVs and PEV-DOX were in the ranges of 120-150 nm and 1.2-6.2 × 10 11 particles/mL for all preparations. The loading of DOX determined using fluorospectrometry was found to be 2.1 × 10 6 , 1.7 × 10 6 , and 0.9 × 10 6 molecules/EV using freeze/thaw, extrusion, and sonication, respectively. The internalization of PEVs was determined to occur through clathrin-mediated endocytosis. PEV-DOX were more efficiently taken up by MDA-MB-231 breast cancer cells compared to MCF7/ADR breast cancer cells and NIH/3T3 cells. DOX-PEVs showed higher anticancer activity against MDA-MB-231 cells than against MCF7/ADR or NIH/3T3 cells and better than acommercial liposomal DOX formulation. In conclusion, this study demonstrates that PEVs generated by PLTs using extrusion, freeze/thaw, or sonication can efficiently load DOX and kill breast cancer cells, providing a promising strategy for further evaluation in preclinical animal models. The study findings suggest that sonication and extrusion are the most efficient methods to generate PEVs and that PEVs loaded with DOX exhibit significant anticancer activity against MDA-MB-231 breast cancer cells.

As an alternative strategy for cancer treatment, the combination of cancer nanomedicine and immunotherapy is promising with regard to efficacy and safety; however, precise modulation of the activation of antitumor immunity remains challenging. Therefore, the aim of the present study was to describe an intelligent nanocomposite polymer immunomodulator, drug-free polypyrrole-polyethyleneimine nanozyme (PPY-PEI NZ), which responds to the B-cell lymphoma tumor microenvironment, for precision cancer immunotherapy. Earlier engulfment of PPY-PEI NZs in an endocytosis-dependent manner resulted in rapid binding in four different types of B-cell lymphoma cells. The PPY-PEI NZ effectively suppressed B cell colony-like growth in vitro accompanied by cytotoxicity via apoptosis induction. During PPY-PEI NZ-induced cell death, mitochondrial swelling, loss of mitochondrial transmembrane potential (MTP), downregulation of antiapoptotic proteins, and caspase-dependent apoptosis were observed. Deregulated AKT and ERK signaling contributed to glycogen synthase kinase-3-regulated cell apoptosis following deregulation of Mcl-1 and MTP loss. Additionally, PPY-PEI NZs induced lysosomal membrane permeabilization while inhibiting endosomal acidification, partly protecting cells from lysosomal apoptosis. PPY-PEI NZs selectively bound and eliminated exogenous malignant B cells in a mixed culture system with healthy leukocytes ex vivo. While PPY-PEI NZs showed no cytotoxicity in wild-type mice, they provided long-term and efficient inhibition of the growth of B-cell lymphoma-driven nodules in a subcutaneous xenograft model. This study explores a potential PPY-PEI NZ-based anticancer agent against B-cell lymphoma., Competing Interests: Conflict of interest statement The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Introduction: Efficacy and safety are critical concerns when designing drug carriers. Nanoparticles are a particular type of carrier that has gained recent attention in cancer therapeutics., Methods: In this study, we assess the safety profile of IT-101, a nanoparticle formed by self-assembly of camptothecin (CPT) conjugated cyclodextrin-based polymers. IT-101 delivers CPT to target cancer cells in animal models of numerous human cancers and in humans. Previous data from preclinical and clinical trials indicate that IT-101 has no notable immunological side effects. However, there have been no published studies focused on evaluating the effects of IT-101 on host immune systems., Results: In this work, we demonstrate that IT-101 diminished initial host immune response following first injection of the nanopharmaceutical and induced NK cell activation and T cell proliferation upon further IT-101 exposure. Additionally, IT-101 could attenuate tumor growth more efficiently than CPT treatment only., Conclusions: Drugs administration in whole-body circulation may lead to poorly bioavailable in central nervous system and often has toxic effects on peripheral tissues. Conjugated with cyclodextrin-based polymers not only reduce adverse effects but also modulate the immune responses to elevate drug efficacy. These immune responses may potentially facilitate actions of immune blockage, such as PD1/PDL1 in cancer treatment.

The molecular pathogenesis of colorectal cancer encompasses the activation of several oncogenic signaling pathways that include the Wnt/β-catenin pathway and the overexpression of high mobility group protein A2 (HMGA2). Resveratrol - the polyphenolic phytoalexin - binds to integrin αvβ3 to induce apoptosis in cancer cells via cyclooxygenase 2 (COX-2) nuclear accumulation and p53-dependent apoptosis. Tetraiodothyroacetic acid (tetrac) is a de-aminated derivative of l-thyroxine (T 4 ), which - in contrast to the parental hormone - impairs cancer cell proliferation. In the current study, we found that tetrac promoted resveratrol-induced anti-proliferation in colon cancer cell lines, in primary cultures of colon cancer cells, and in vivo The mechanisms implicated in this action involved the downregulation of nuclear β-catenin and HMGA2, which are capable of compromising resveratrol-induced COX-2 nuclear translocation. Silencing of either β-catenin or HMGA2 promoted resveratrol-induced anti-proliferation and COX-2 nuclear accumulation which is essential for integrin αvβ3-mediated-resveratrol-induced apoptosis in cancer cells. Concurrently, tetrac enhanced nuclear abundance of chibby family member 1, the nuclear β-catenin antagonist, which may further compromise the nuclear β-catenin-dependent gene expression and proliferation. Taken together, these results suggest that tetrac targets β-catenin and HMGA2 to promote resveratrol-induced-anti-proliferation in colon cancers, highlighting its potential in anti-cancer combination therapy., (© 2018 Society for Endocrinology.)