Discovery of Novel 5,6-Dihydro-4H-pyrido[2,3,4-de]quinazoline Irreversible Inhibitors Targeting Both Wild-Type and A775_G776insYVMA Mutated HER2 Kinases.

HER2 mutations were seen in 4% of non-small-cell lung cancer (NSCLC) patients. Most of these mutations (90%) occur as an insertion mutation within the exon 20 frame, leading to the downstream activation of the PI3K-AKT and RAS/MAPK pathways. However, no targeted therapies have yet been approved worldwide. Here a novel series of highly potent HER2 inhibitors with a pyrido[2,3,4-de]quinazoline core were designed and developed. The derivatives with the pyrido[2,3,4-de]quinazoline core displayed superior efficacy of antiproliferation in BaF3 cells harboring HER2insYVMA mutation compared with afatinib and neratinib. Rat studies showed that 8a and 9a with the newly developed core have good pharmacokinetic properties with an oral bioavailability of 41.7 and 42.0%, respectively. Oral administration of 4a and 10e (30 mg/kg, QD) displayed significant antitumor efficacy in an in vivo xenograft model. We proposed promising strategies for the development of HER2insYVMA mutant inhibitors in this study.

Balloon dilation for the treatment of male urethral strictures: a systematic review and meta-analysis.

OBJECTIVE: The use of minimally invasive endoluminal treatment for urethral strictures has been a subject for debate for several decades. The aim of this study was to review and discuss the safety, efficacy and factors influencing the clinical application of balloon dilation for the treatment of male urethral strictures. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Embase, Medline, Web of Science, Cochrane Library and Scopus were searched for publications published before 17 July 2022. STUDY SELECTION: Two independent researchers screened and assessed the results, and all clinical studies on balloon dilation for the treatment of urethral strictures in men were included. DATA EXTRACTION AND SYNTHESIS: The success rate, rate of adverse events, International Prostate Symptom Scores, maximum uroflow (Qmax) and postvoid residual urine volume were the main outcomes. Stata V.14.0 was used for statistical analysis. RESULTS: Fifteen studies with 715 patients were ultimately included in this systematic review. The pooled results of eight studies showed that the reported success rate of simple balloon dilation for male urethral strictures was 67.07% (95% confidence interval [CI]: 55.92% to 77.36%). The maximum urinary flow rate at 3 months (risk ratio [RR]= 2.6510, 95% CI: 1.0681 to 4.2338, p<0.01) and the maximum urinary flow rate at 1 year (RR= 1.6637, 95% CI: 1.1837 to 2.1437, p<0.05) were significantly different after dilation. There is insufficient evidence to suggest that balloon dilation is superior to optical internal urethrotomy or direct visual internal urethrotomy (DVIU) (RR= 1.4754, 95% CI: 0.7306 to 2.9793, p=0.278). CONCLUSION: Balloon dilation may be an intermediate step before urethroplasty and is a promising alternative therapy to simple dilation and DVIU. The balloon is a promising drug delivery tool, and paclitaxel drug-coated balloon dilation is effective in reducing retreatment rates in patients with recurrent anterior urethral strictures. The aetiology, location, length, previous treatment of urethral stricture may be associated with the efficacy of balloon dilation. PROSPERO REGISTRATION NUMBER: CRD42022334403.

The Regenerative Microenvironment of the Tissue Engineering for Urethral Strictures.

Urethral stricture caused by various reasons has threatened the quality of life of patients for decades. Traditional reconstruction methods, especially for long-segment injuries, have shown poor outcomes in treating urethral strictures. Tissue engineering for urethral regeneration is an emerging concept in which special designed scaffolds and seed cells are used to promote local urethral regeneration. The scaffolds, seed cells, various factors and the host interact with each other and form the regenerative microenvironment. Among the various interactions involved, vascularization and fibrosis are the most important biological processes during urethral regeneration. Mesenchymal stem cells and induced pluripotent stem cells play special roles in stricture repair and facilitate long-segment urethral regeneration, but they may also induce carcinogenesis and genomic instability during reconstruction. Nevertheless, current technologies, such as genetic engineering, molecular imaging, and exosome extraction, provide us with opportunities to manage seed cell-related regenerative risks. In this review, we described the interactions among seed cells, scaffolds, factors and the host within the regenerative microenvironment, which may help in determining the exact molecular mechanisms involved in urethral stricture regeneration and promoting clinical trials and the application of urethral tissue engineering in patients suffering from urethral stricture.

Adipose stem cells in tissue regeneration and repair: From bench to bedside.

ADSCs are a large number of mesenchymal stem cells in Adipose tissue, which can be applied to tissue engineering. ADSCs have the potential of multi-directional differentiation, and can differentiate into bone tissue, cardiac tissue, urothelial cells, skin tissue, etc. Compared with other mesenchymal stem cells, ADSCs have a multitude of promising advantages, such as abundant number, accessibility in cell culture, stable function, and less immune rejection. There are two main methods to use ADSCs for tissue repair and regeneration. One is to implant the "ADSCs-scaffold composite" into the injured site to promote tissue regeneration. The other is cell-free therapy: using ADSC-exos or ADSC-CM alone to release a large number of miRNAs, cytokines and other bioactive substances to promote tissue regeneration. The tissue regeneration potential of ADSCs is regulated by a variety of cytokines, signaling molecules, and external environment. The differentiation of ADSCs into different tissues is also induced by growth factors, ions, hormones, scaffold materials, physical stimulation, and other factors. The specific mechanisms are complex, and most of the signaling pathways need to be further explored. This article reviews and summarizes the mechanism and clinical application of ADSCs in tissue injury repair so far, and puts forward further problems that need to be solved in this field, hoping to provide directions for further research in this field.