Targeted paclitaxel prodrug nanoassemblies to improve therapeutic effects for liver cancer.

Prodrug nanoassemblies fabricated by anticancer drug conjugates exhibited more advantages in controlled drug release and bioavailability and favorable antitumor efficacy. In this paper, lactobionic acid (LA) was connected with polyethylene glycol through amido linkages, and paclitaxel was joined with polyethylene glycol by means of ester bonds to form the prodrug copolymer LA-PEG-PTX. Then, LA-PEG-PTX was automatically assembled into LA-PEG-PTX nanoparticles (LPP NPs) by dialysis. The LPP NPs had a relatively uniform size of approximately 200 nm, a negative potential (-13.68 mV), and a spherical shape under TEM. The drug loading of LPP NPs was 3.91%, which was measured by HPLC. The in vitro release profile of LPP NPs exhibited a sustained release feature. The results of the pharmacokinetic test in rats showed that LPP NPs had higher T1/2 and AUC values than the control group (free PTX) and a prolonged in vivo circulation time, thus increasing the bioavailability of PTX. Remarkably, the LPP NPs were absorbed into HepG2 cells after galactose-directed internalization and enhanced cytotoxicity. Consequently, LPP NPs displayed notable antitumor activity in Kunming mice with H22 hepatocellular carcinoma. Collectively, these findings suggested that paclitaxel prodrug-based self-assembled nanoparticles were a promising alternative for improving the bioavailability and antitumor effect of PTX.

Discovery of a novel and potent inhibitor with differential species-specific effects against NLRP3 and AIM2 inflammasome-dependent pyroptosis.

The NLRP3 inflammasome, which regulated a proinflammatory programmed cell death form termed pyroptosis, is involved in the pathological process of various human diseases, such as multiple sclerosis, type 2 diabetes, and gout. Thus, compounds inhibiting activation of the NLRP3 inflammasome can be promising treatments for these diseases. In this study, we conducted a phenotypic screening against NLRP3-dependent pyroptosis and discovered the hit compound 1, which showed moderate antipyroptotic activity. Chemistry efforts to improve potency of 1 resulted in a novel compound 59 (J114), which exhibited a half-maximal inhibitory concentration (IC50) of 0.077 ± 0.008 µM against cell pyroptosis. Interestingly, unlike all pyroptosis inhibitors currently reported, the activity of J114 showed significant differences in human- and mouse-derived cells. The IC50 of J114-mediated inhibition of IL-1ß secretion by human THP-1 macrophages was 0.098 µM, which was nearly 150-fold and 500-fold more potent than that of J774A.1 (14.62 µM) and bone marrow-derived macrophages (BMDMs) (48.98 µM), respectively. Further studies showed that J114 displayed remarkable inhibitory activity against NLRP3- and AIM2-but not NLRC4-dependent activation of caspase-1 and the release of IL-1ß in human THP-1 macrophages. Mechanistically, J114 disturbed the interaction of NLRP3 or AIM2 with the adaptor protein ASC and inhibited ASC oligomerization. Overall, our study identified a unique molecule that inhibits NLRP3 and AIM2 inflammasome activation and has species differences, which is worthy of further research to understand the differential regulation of the NLRP3 and AIM2 inflammasomes in humans and mice.

Structural Optimization and Structure-Activity Relationship Studies of 6,6-Dimethyl-4-(phenylamino)-6H-pyrimido[5,4-b][1,4]oxazin-7(8H)-one Derivatives as A New Class of Potent Inhibitors of Pan-Trk and Their Drug-Resistant Mutants.

Tropomyosin receptor kinases (TrkA, TrkB, and TrkC) are attractive therapeutic targets for multiple cancers. Two first-generation small-molecule Trks inhibitors, larotrectinib and entrectinib, have just been approved to use clinically. However, the drug-resistance mutations of Trks have already emerged, which calls for new-generation Trks inhibitors. Herein, we report the structural optimization and structure-activity relationship studies of 6,6-dimethyl-4-(phenylamino)-6H-pyrimido[5,4-b][1,4]oxazin-7(8H)-one derivatives as a new class of pan-Trk inhibitors. The prioritized compound 11g exhibited low nanomolar IC50 values against TrkA, TrkB, and TrkC and various drug-resistant mutants. It also showed good kinase selectivity. 11g displayed excellent in vitro antitumor activity and strongly suppressed Trk-mediated signaling pathways in intact cells. In in vivo studies, compound 11g exhibited good antitumor activity in BaF3-TEL-TrkA and BaF3-TEL-TrkCG623R allograft mouse models without exhibiting apparent toxicity. Collectively, 11g could be a promising lead compound for drug discovery targeting Trks and deserves further investigation.

Codon optimization with deep learning to enhance protein expression.

Heterologous expression is the main approach for recombinant protein production ingenetic synthesis, for which codon optimization is necessary. The existing optimization methods are based on biological indexes. In this paper, we propose a novel codon optimization method based on deep learning. First, we introduce the concept of codon boxes, via which DNA sequences can be recoded into codon box sequences while ignoring the order of bases. Then, the problem of codon optimization can be converted to sequence annotation of corresponding amino acids with codon boxes. The codon optimization models for Escherichia Coli were trained by the Bidirectional Long-Short-Term Memory Conditional Random Field. Theoretically, deep learning is a good method to obtain the distribution characteristics of DNA. In addition to the comparison of the codon adaptation index, protein expression experiments for plasmodium falciparum candidate vaccine and polymerase acidic protein were implemented for comparison with the original sequences and the optimized sequences from Genewiz and ThermoFisher. The results show that our method for enhancing protein expression is efficient and competitive.

[Clinical analysis of sudden deafness after radiotherapy and chemotherapy in nasopharyngeal carcinoma patients].

OBJECTIVE: To investigate the clinical features and therapeutic effects of sudden deafness after radiotherapy combined with chemotherapy in nasopharyngeal carcinoma patients. METHOD: Clinical data of 42 nasopharyngeal carcinoma patients suffered from sudden deafness after radiotherapy combined with chemotherapy were analyzed retrospectively. Among the 42 patients, 2 showed moderate deafness, 4 presented excessive deafness, 30 suffered from severe deafness, and 6 exhibited profound deafness. The audiogram pattern of 33 patients met with the type of high tone frequencies hearing loss, and that of the rest 9 cases showed hearing loss at all frequencies. All patients received medical therapy combined with hyperbaric oxygen therapy. RESULT: Of all the cases with hearing loss, 2 were cured, 2 showed excellent recovery, 9 came out partial recovery, and 29 showed no response to the treatment. The total effective rate was 30.95%. For the accompanied symptoms, none of the 30 cases of tinnitus were relieved, 3 out of 10 cases of aural fullness were cured, and the 5 cases of dizziness or vertigo were all improved. CONCLUSION: The sudden deafness after radiotherapy combined with chemotherapy in patients with nasopharyngeal carcinoma is closely related to radiotherapy. The hearing loss is serious, and the therapeutic effects are not satisfactory.