Lymph-Node-Targeted Cholesterolized TLR7 Agonist Liposomes Provoke a Safe and Durable Antitumor Response

Toll-like receptor (TLR) agonists as the potent stimulants of an innate immune system hold promises for applications in anticancer immunotherapy. However, most of them are limited in the clinical translation due to the uncontrolled systemic inflammatory response. In the current study, 1V209, a small molecule TLR7 agonist, was conjugated with cholesterol (1V209-Cho) and prepared into liposomes (1V209-Cho-Lip). 1V209-Cho-Lip exerted minimal toxic effects and enhanced the transportation ability in lymph nodes (LNs) compared with 1V209. 1V209-Cho-Lip treatment inhibited tumor progression in CT26 colorectal cancer, 4T1 breast cancer, and Pan02 pancreatic ductal cancer models through inducing effective DC activation and eliciting CD8+ T cell responses. Furthermore, 1V209-Cho-Lip induced tumor-specific memory immunity to inhibit cancer recurrence and metastasis. These results indicate that cholesterol conjugation with 1V209 is an effective approach to target lymph nodes and to reduce the adverse effects. This work provides a rational basis for the distribution optimization of TLR agonists for potential clinical use

Multimode MicroRNA Sensing via Multiple Enzyme-Free Signal Amplification and Cation-Exchange Reaction

The detection of biomarkers requires not only high sensitivity but also different signal reading methods depending on the actual situation. Herein, the luminescent properties of CdTe quantum dots (QDs) were exploited, where CdTe QDs were used as shared signal molecules. Combining multiple types of nucleic acid and chemical signal amplification techniques, and various signal detection techniques, a magnetic nanoparticle (NP) and filter-assisted separation multimode sensing strategy has been developed. In this work, miRNA-141 was selected as a representative target, which can trigger the catalyzed hairpin assembly and hybrid chain reaction enzyme-free nucleic acid signal amplification that generates long double-stranded DNA. Subsequently, the chemical amplification of silver NPs (Ag NPs) that release a large amount of Ag+ was introduced into the system. Finally, the cation-exchange reaction between CdTe QDs and Ag+ was utilized to quench the fluorescence (FL) of the CdTe QDs, releasing free Cd2+. The visual/FL/chemical vapor generation-atomic fluorescence spectrometry (CVG-AFS)/inductively coupled plasma mass spectrometry (ICP-MS) method could then be performed for the analysis of miRNA. After investigating its experimental performance, it has been found that 10 fM can be differentiated from the blank solution with the naked eye. In addition, FL/CVG-AFS/ICP-MS methods all displayed good analytical capability for target detection, and the limits of detection (LODs) are as low as fM, which show high target sequence selectivity. This platform was applied to investigate miRNA-141 expression in various cancer cells, which can accurately detect in the range of 100–100 000 MDA-MB-231 cells (breast cancer cell lines), with an LOD of 15 cells. Therefore, the multimode sensing strategy based on a single signal molecule and multiple signal amplification strategies is an applicable and versatile detection method of biomarkers; it can even achieve point-of-care testing, improving the accuracy and efficiency of medical diagnosis

Modular Engineering of Targeted Dual-Drug Nanoassemblies for Cancer Chemoimmunotherapy

Combination of chemotherapeutics and immunomodulators can generate synergistic anticancer efficacy, exerting efficient chemoimmunotherapy for cancer treatment. Nanoparticulate delivery systems hold great promise to promote synergistic anticancer efficacy for the codelivery of drugs. However, there remain challenges to precisely coencapsulate and deliver combinational drugs at designed ratios due to the difference of compatibility between drugs and nanocarriers. In this study, coassembled nanoparticles of lipophilic prodrugs (LPs) were designed to codeliver chemotherapeutics and immunomodulators for cancer treatment. Such nanoassemblies (NAs) could act as platforms to ratiometrically coencapsulate chemotherapeutics and immunomodulators. Based on this method, NAs formed by the self-assembly of iRGD peptide derivatives, paclitaxel (PTX) LPs, and imiquimod (R837) LPs were demonstrated to target the tumor at unified pharmacokinetics, further inducing the effective tumor inhibition and tumor recurrence prevention. This work provided an alternative to prepare chemoimmunotherapeutic NAs with advantages of ratiometric drug coencapsulation and unified pharmacokinetics, which may advance the future cancer chemoimmunotherapy

Autophagy impairment with lysosomal and mitochondrial dysfunction is an important characteristic of oxidative stress-induced senescence

<p>Macroautophagy/autophagy has profound implications for aging. However, the true features of autophagy in the progression of aging remain to be clarified. In the present study, we explored the status of autophagic flux during the development of cell senescence induced by oxidative stress. In this system, although autophagic structures increased, the degradation of SQSTM1/p62 protein, the yellow puncta of mRFP-GFP-LC3 fluorescence and the activity of lysosomal proteolytic enzymes all decreased in senescent cells, indicating impaired autophagic flux with lysosomal dysfunction. The influence of autophagy activity on senescence development was confirmed by both positive and negative autophagy modulators; and MTOR-dependent autophagy activators, rapamycin and PP242, efficiently suppressed cellular senescence through a mechanism relevant to restoring autophagic flux. By time-phased treatment of cells with the antioxidant N-acetylcysteine (NAC), the mitochondria uncoupler carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and ambroxol, a reagent with the effect of enhancing lysosomal enzyme maturation, we found that mitochondrial dysfunction plays an initiating role, while lysosomal dysfunction is more directly responsible for autophagy impairment and senescence. Interestingly, the effect of rapamycin on autophagy flux is linked to its role in functional revitalization of both mitochondrial and lysosomal functions. Together, this study demonstrates that autophagy impairment is crucial for oxidative stress-induced cell senescence, thus restoring autophagy activity could be a promising way to retard senescence.</p

Artificial Virus Delivers CRISPR-Cas9 System for Genome Editing of Cells in Mice

CRISPR-Cas9 has emerged as a versatile genome-editing platform. However, due to the large size of the commonly used CRISPR-Cas9 system, its effective delivery has been a challenge and limits its utility for basic research and therapeutic applications. Herein, a multifunctional nucleus-targeting “core-shell” artificial virus (RRPHC) was constructed for the delivery of CRISPR-Cas9 system. The artificial virus could efficiently load with the CRISPR-Cas9 system, accelerate the endosomal escape, and promote the penetration into the nucleus without additional nuclear-localization signal, thus enabling targeted gene disruption. Notably, the artificial virus is more efficient than SuperFect, Lipofectamine 2000, and Lipofectamine 3000. When loaded with a CRISPR-Cas9 plasmid, it induced higher targeted gene disruption efficacy than that of Lipofectamine 3000. Furthermore, the artificial virus effectively targets the ovarian cancer <i>via</i> dual-receptor-mediated endocytosis and had minimum side effects. When loaded with the Cas9-hMTH1 system targeting MTH1 gene, RRPHC showed effective disruption of MTH1 <i>in vivo</i>. This strategy could be adapted for delivering CRISPR-Cas9 plasmid or other functional nucleic acids <i>in vivo</i>