Rational design of a polysaccharide-based viral mimicry nanocomplex for potent gene silencing in inflammatory tissues.

Rational design and fabrication of small interfering RNA (siRNA) delivery system with simple production scheme, specific targeting capability, responsiveness to endogenous stimuli and potential multi-functionalities remains technically challenging. Herein, we screen and design a virus-mimicking polysaccharide nanocomplex that shows specific gene delivery capability in a selective subset of leukocytes. A virus-inspired poly (alkyl methacrylate-co-methacrylic acid) fragment was conjugated on barley ß-glucans (EEPG) to endow the nanocomplex with pH-dependent endosomal membrane destabilization capabilities, as confirmed both biologically and computationally. siRNA loaded EEPG nanocomplex is feasibly fabricated in a single-step manner, which exhibit efficient gene silencing efficacy towards Dectin-1+ monocytes/macrophages. The inherent targeting affinity and feasible gene silencing potency of EEPG nanocomplex are investigated in three independent murine inflammation models, including myocardial infarction, lung fibrosis and acute liver damage. Significant enhanced accumulation level of EEPG nanocomplex is observed in cardiac lesion site, indicating its exclusive targeting capability for ischemic heart diseases. As a proof of concept, siTGF-ß based gene therapy is confirmed in murine model with heart fibrosis. Overall, our findings suggest the designed EEPG nanocomplex is favorable for siRNA delivery, which might have translational potential as a versatile platform in inflammation-related diseases.

The aldolase inhibitor aldometanib mimics glucose starvation to activate lysosomal AMPK.

The activity of 5'-adenosine monophosphate-activated protein kinase (AMPK) is inversely correlated with the cellular availability of glucose. When glucose levels are low, the glycolytic enzyme aldolase is not bound to fructose-1,6-bisphosphate (FBP) and, instead, signals to activate lysosomal AMPK. Here, we show that blocking FBP binding to aldolase with the small molecule aldometanib selectively activates the lysosomal pool of AMPK and has beneficial metabolic effects in rodents. We identify aldometanib in a screen for aldolase inhibitors and show that it prevents FBP from binding to v-ATPase-associated aldolase and activates lysosomal AMPK, thereby mimicking a cellular state of glucose starvation. In male mice, aldometanib elicits an insulin-independent glucose-lowering effect, without causing hypoglycaemia. Aldometanib also alleviates fatty liver and nonalcoholic steatohepatitis in obese male rodents. Moreover, aldometanib extends lifespan and healthspan in both Caenorhabditis elegans and mice. Taken together, aldometanib mimics and adopts the lysosomal AMPK activation pathway associated with glucose starvation to exert physiological roles, and might have potential as a therapeutic for metabolic disorders in humans.

Discovery of 4-methyl-N-(4-((4-methylpiperazin- 1-yl)methyl)-3-(trifluoromethyl)phenyl)-3-((6-(pyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-yl)-oxy)benzamide as a potent inhibitor of RET and its gatekeeper mutant.

The receptor tyrosine kinase rearranged during transfection (RET) plays pivotal roles in several cancers, including thyroid carcinoma and non-small cell lung cancer (NSCLC). Currently, there are several FDA-approved RET inhibitors, but their indication is limited to thyroid cancer, and none can overcome their gatekeeper mutants (V804L and V804M). Here, we report the discovery of 9x representing a new chemotype of potent and selective RET inhibitors, using a rational design strategy of type II kinase inhibitors. 9x exhibited both superior antiproliferative activities against NSCLC-related carcinogenic fusions KIF5B-RET and CCDC6-RET and gatekeeper mutant-transformed Ba/F3 cells, with the lowest GI50 of 9 nM, and substantial inhibitory activities against wild-type RET and RET mutant proteins, with the best IC50 of 4 nM. More importantly, 9x also showed nanomole potency against RET-positive NSCLC cells LC-2/ad, but not against a panel of RET-negative cancer cells, such as A549, H3122, A375 or parental Ba/F3 cells, demonstrating its selective 'on-target' effect. In mouse xenograft models, 9x repressed tumor growth driven by both wild type KIF5B-RET-Ba/F3 and gatekeeper mutant KIF5B-RET(V804M)-Ba/F3 cells in a dose-dependent manner. Together, these data establish that 9x provides a good starting point for the development of targeted therapeutics against RET-positive cancers, especially NSCLC.

Tandem-Mass-Tag Based Proteomic Analysis Facilitates Analyzing Critical Factors of Porous Silicon Nanoparticles in Determining Their Biological Responses under Diseased Condition.

The analysis of nanoparticles' biocompatibility and immunogenicity is mostly performed under a healthy condition. However, more clinically relevant evaluation conducted under pathological condition is less known. Here, the immunogenicity and bio-nano interactions of porous silicon nanoparticles (PSi NPs) are evaluated in an acute liver inflammation mice model. Interestingly, a new mechanism in which PSi NPs can remit the hepatocellular damage and inflammation activation in a surface dependent manner through protein corona formation, which perturbs the inflammation by capturing the pro-inflammatory signaling proteins that are inordinately excreted or exposed under pathological condition, is found. This signal sequestration further attenuates the nuclear factor κB pathway activation and cytokines production from macrophages. Hence, the study proposes a potential mechanism for elucidating the altered immunogenicity of nanomaterials under pathological conditions, which might further offer insights to establish harmonized standards for assessing the biosafety of biomaterials in a disease-specific or personalized manner.

Pharmacological Targeting of Vacuolar H+-ATPase via Subunit V1G Combats Multidrug-Resistant Cancer.

Multidrug resistance (MDR) in cancer remains a major challenge for the success of chemotherapy. Natural products have been a rich source for the discovery of drugs against MDR cancers. Here, we applied high-throughput cytotoxicity screening of an in-house natural product library against MDR SGC7901/VCR cells and identified that the cyclodepsipeptide verucopeptin demonstrated notable antitumor potency. Cytological profiling combined with click chemistry-based proteomics revealed that ATP6V1G directly interacted with verucopeptin. ATP6V1G, a subunit of the vacuolar H+-ATPase (v-ATPase) that has not been previously targeted, was essential for SGC7901/VCR cell growth. Verucopeptin exhibited strong inhibition of both v-ATPase activity and mTORC1 signaling, leading to substantial pharmacological efficacy against SGC7901/VCR cell proliferation and tumor growth in vivo. Our results demonstrate that targeting v-ATPase via its V1G subunit constitutes a unique approach for modulating v-ATPase and mTORC1 signaling with great potential for the development of therapeutics against MDR cancers.

Hierarchical structured and programmed vehicles deliver drugs locally to inflamed sites of intestine.

Orally administrable drug delivery vehicles are developed to manage incurable inflammatory bowel disease (IBD), however, their therapeutic outcomes are compromised by the side effects of systemic drug exposure. Herein, we use hyaluronic acid functionalized porous silicon nanoparticle to bridge enzyme-responsive hydrogel and pH-responsive polymer, generating a hierarchical structured (nano-in-nano-in-micro) vehicle with programmed properties to fully and sequentially overcome the multiple obstacles for efficiently delivering drugs locally to inflamed sites of intestine. After oral administration, the pH-responsive matrix protects the embedded hybrid nanoparticles containing drug loaded hydrogels against the spatially variable physiological environments of the gastrointestinal tract until they reach the inflamed sites of intestine, preventing premature drug release. The negatively charged hybrid nanoparticles selectively target the inflamed sites of intestine, and gradually release drug in response to the microenvironment of inflamed intestine. Overall, the developed hierarchical structured and programmed vehicles load, protect, transport and release drugs locally to inflamed sites of intestine, contributing to superior therapeutic outcomes. Such strategy could also inspire the development of numerous hierarchical structured vehicles by other porous nanoparticles and stimuli-responsive materials for the local delivery of various drugs to treat plenty of inflammatory gastrointestinal diseases, including IBD, gastrointestinal cancers and viral infections.