Human Adipose Tissue Lysate-Based Hydrogel for Lasting Immunomodulation to Effectively Improve Spinal Cord Injury Repair.

The long-term inflammatory microenvironment is one of the main obstacles to inhibit acute spinal cord injury (SCI) repair. The natural adipose tissue-derived extracellular matrix hydrogel shows effective anti-inflammatory regulation because of its unique protein components. However, the rapid degradation rate and removal of functional proteins during the decellularization process impair the lasting anti-inflammation function of the adipose tissue-derived hydrogel. To address this problem, adipose tissue lysate provides an effective way for SCI repair due to its abundance of anti-inflammatory and nerve regeneration-related proteins. Thereby, human adipose tissue lysate-based hydrogel (HATLH) with an appropriate degradation rate is developed, which aims to in situ long-term recruit and induce anti-inflammatory M2 macrophages through sustainedly released proteins. HATLH can recruit and polarize M2 macrophages while inhibiting pro-inflammatory M1 macrophages regardless of human or mouse-originated. The axonal growth of neuronal cells also can be effectively improved by HATLH and HATLH-induced M2 macrophages. In vivo experiments reveal that HATLH promotes endogenous M2 macrophages infiltration in large numbers (3.5 × 105/100 µL hydrogel) and maintains a long duration for over a month. In a mouse SCI model, HATLH significantly inhibits local inflammatory response, improves neuron and oligodendrocyte differentiation, enhances axonal growth and remyelination, as well as accelerates neurological function restoration.

Discovery of small molecule Gαq/11 protein inhibitors against uveal melanoma.

Constitutively activated G proteins caused by specific mutations mediate the development of multiple malignancies. The mutated Gαq/11 are perceived as oncogenic drivers in the vast majority of uveal melanoma (UM) cases, making directly targeting Gαq/11 to be a promising strategy for combating UM. Herein, we report the optimization of imidazopiperazine derivatives as Gαq/11 inhibitors, and identified GQ262 with improved Gαq/11 inhibitory activity and drug-like properties. GQ262 efficiently blocked UM cell proliferation and migration in vitro. Analysis of the apoptosis-related proteins, extracellular signal-regulated kinase (ERK), and yes-associated protein (YAP) demonstrated that GQ262 distinctly induced UM cells apoptosis and disrupted the downstream effectors by targeting Gαq/11 directly. Significantly, GQ262 showed outstanding antitumor efficacy in vivo with good safety at the testing dose. Collectively, our findings along with the favorable pharmacokinetics of GQ262 revealed that directly targeting Gαq/11 may be an efficient strategy against uveal melanoma.

Synthesis and evaluation of imidazo[1,2-a]pyrazine derivatives as small molecule Gαq/11 inhibitors against uveal melanoma.

Uveal melanoma (UM) is an aggressive malignancy with high mortality in adults and lacks effective systemic therapies. Activating gene mutations related to the Gαq/11 signaling pathway are prevalent in UM, and Gαq/11 inhibitors have shown anti-UM activity in vitro and in vivo. In this study, we designed and synthesized a series of imidazo[1,2-a]pyrazine derivatives as Gαq/11 inhibitors, and discovered GQ352 with the selective antiproliferative activity against UM cells. Importantly, GQ352 directly binds to the Gαq and inhibits the dissociation of Gαßγ heterotrimers with the IC50 value of 8.9 µM. GQ352 inhibits UM tumorigenesis by suppressing Gαq/11 downstream ERK phosphorylation and YAP dephosphorylation, as shown in Western blot analysis. In addition, GQ352 displayed reasonable physiochemical properties and human liver microsome stability, indicating the potential application in UM treatment.

Cleavable and tunable cysteine-specific arylation modification with aryl thioethers.

Cysteine represents an attractive target for peptide/protein modification due to the intrinsic high nucleophilicity of the thiol group and low natural abundance. Herein, a cleavable and tunable covalent modification approach for cysteine containing peptides/proteins with our newly designed aryl thioethers via a S N Ar approach was developed. Highly efficient and selective bioconjugation reactions can be carried out under mild and biocompatible conditions. A series of aryl groups bearing different bioconjugation handles, affinity or fluorescent tags are well tolerated. By adjusting the skeleton and steric hindrance of aryl thioethers slightly, the modified products showed a tunable profile for the regeneration of the native peptides.

Design, Synthesis, and Evaluation of Small Molecule Gαq/11 Protein Inhibitors for the Treatment of Uveal Melanoma.

Uveal melanoma is the ocular malignancy and mainly driven by oncogenic mutations of Gαq/11 proteins. Previous targeted therapy for melanoma treatment was limited to specific downstream signaling pathway, and inhibiting the "molecular switches" G proteins for melanoma treatment therapy was rarely described. We herein report the discovery of imidazopiperazine derivatives as Gαq/11 protein inhibitors. The most promising compound GQ127 showed good efficacy and safety in inositol monophosphate (IP1) assay by directly inhibiting Gαq/11 proteins. GQ127 induced uveal melanoma cells apoptosis and displayed potent antitumor activities in uveal melanoma cells viability, migration, and invasion. The effects of GQ127 on Gαq/11 signaling pathway were confirmed by analyzing the downstream effectors yes-associated protein (YAP) and extracellular signal-regulated kinase (ERK). More importantly, GQ127 significantly suppressed UM xenograft growth in mouse model without severe toxicity at the testing dose. These findings provide a lead compound that directly targets the Gαq/11 proteins for uveal melanoma treatment.

ATP triggered drug release and DNA co-delivery systems based on ATP responsive aptamers and polyethylenimine complexes.

Stimuli-responsive nanocarriers for anticancer drug and gene co-delivery are a promising strategy in cancer therapy due to their combination of chemotherapy and gene therapy. In this work, we developed a facile and effective method to fabricate stimuli-responsive nanocarriers for anticancer drug and gene co-delivery based on complexes of polyethylenimine (PEI) with an adenosine triphosphate (ATP) responsive aptamer duplex (ARAD). No chemical reactions or complex modifications were used in the construction processes. In this system, Doxorubicin-loaded aptamer duplex and plasmid DNA (p53) can be bound by PEI by electronic interactions to form stable complexes which effectively protect the aptamer and p53 from DNase degradation. The intercalated Dox can be released on-demand by a structural change in the aptamer duplex in an ATP-rich environment. The morphology and average size of the nanocarriers were characterized by zeta potential and transmission electron microscopy (TEM). The nanocarriers exhibit lower cell toxicity in HeLa cell lines relative to PEI. RT-PCR and Western blot analysis confirmed that p53 could be effectively delivered and expressed in HeLa cells by PEI/ARAD/p53 complexes. Moreover, the apoptosis percentage of HeLa cells treated with PEI/ARAD/Dox/p53 complex increased to 40.8%, compared to 24.7% for PEI/ARAD/Dox complex and 11.5% for PEI/ARAD/p53, respectively. The result demonstrated that the combinatorial delivery of Dox and p53 by nanocarriers could induce synergistic actions and lead to effective cancer cell apoptosis.

Efficient gene transfection in the neurotypic cells by star-shaped polymer consisting of ß-cyclodextrin core and poly(amidoamine) dendron arms.

In order to develop the effective vectors that had high gene transfection capability and low cytotoxicity in the neuronal cells, we tested the star-shaped polymer consisting of ß-cyclodextrin core and poly(amidoamine) (PAMAM) dendron arms [ß-CD-(D3)7] as the vector to transfect the human neuroblastoma SH-SY5Y cells. The physicochemical properties of the ß-CD-(D3)7/plasmid DNA (pDNA) complexes were characterized by using gel electrophoresis, dynamic light scattering, transmission electron microscopy and zeta-potential experiments. Among the human neuroblastoma SH-SY5Y cells, ß-CD-(D3)7/pDNA complex demonstrated a lower toxicity compared to those of PAMAM (G=4, with an ethylenediamine core)/pDNA complex. When the N/P ratio was over 20, it was observed that PAMAM had a faster increment in toxicity compared to ß-CD-(D3)7. Fluorescent image, confocal microscopy image and flow cytometry showed that ß-CD-(D3)7/pDNA complexes had significantly higher transgene activity than that of PAMAM/pDNA complexes. For example, the transfection efficiency was 20% and 7.5% for ß-CD-(D3)7/pDNA and PAMAM/pDNA complexes, respectively. These results indicated that ß-CD-(D3)7 might be a promising candidate for neurotypic cells gene delivery with the characteristics of good biocompatibility, relatively high gene transfection capability and potential in vivo gene delivery ability.