Crosstalk among Alternative Polyadenylation, Genetic Variants and Ubiquitin Modification Contribute to Lung Adenocarcinoma Risk.

Ubiquitin modification and alternative polyadenylation play crucial roles in the onset and progression of cancer. Hence, this study aims to comprehensively and deeply understand gene regulation and associated biological processes in lung adenocarcinoma (LUAD) by integrating both mechanisms. Alternative polyadenylation (APA)-related E3 ubiquitin ligases in LUAD were identified through multiple databases, and the association between selected genetic loci influencing gene expression (apaQTL-SNPs) and LUAD risk were evaluated through the GWAS database of the Female Lung Cancer Consortium in Asia (FLCCA). Subsequently, the interaction between RNF213 and ZBTB20, as well as their functional mechanisms in LUAD, were investigated using bioinformatics analysis, Western blot, co-immunoprecipitation, and colony formation experiments. A total of five apaQTL-SNPs (rs41301932, rs4494603, rs9890400, rs56066320, and rs41301932), located on RNF213, were significantly associated with LUAD risk (p < 0.05), and they inhibit tumor growth through ubiquitin-mediated degradation of ZBTB20.

Plasma GPI and PGD are associated with vascular normalization and may serve as novel prognostic biomarkers for lung adenocarcinoma: Multi-omics and multi-dimensional analysis.

The aim of this study was to explore potential novel plasma protein biomarkers for lung adenocarcinoma (LUAD). A plasma proteomics analysis was carried out and candidate protein biomarkers were validated in 102 LUAD cases and 102 matched healthy controls. The same LUAD tumor tissues were detected to explore the correlation between the expression of candidate proteins in tissues and plasma and vascular normalization. A LUAD active metastasis mice model was constructed to explore the role of candidate proteins for lung metastasis. GPI and PGD were verified to be upregulated in plasma from LUAD patients, and the expression of GPI in tumor tissue was positively correlated with the expression of GPI in plasma and negatively correlated with the normalization of tumor blood vessels. Meanwhile, a negative correlation between the expression of GPI and PGD in plasma and tumor vascular normalization was discovered. In the LUAD active metastasis model, the lowest levels of vascular normalization and the highest expression of GPI and PGD were found in mice with lung metastases. This study found that GPI and PGD may be potential plasma biomarkers for LUAD, and monitoring those may infer the risk of metastasis and malignancy of the tumor. SIGNIFICANT: We identified GPI and PGD as potential novel diagnostic and prognostic biomarkers for LUAD. PGD and GPI can be used as diagnostic biomarkers in combination with other available strategies to assist in the screening and diagnosis of LUAD, and as prognostic biomarkers aid in predict the risk of tumor metastasis and malignancy in patients with LUAD.

Integrating apaQTL and eQTL analysis identifies a potential causal variant associated with lung adenocarcinoma risk in the Chinese population.

Alternative polyadenylation (APA) plays a crucial role in cancer biology. Here, we used data from the 3'aQTL-atlas, GTEx, and the China Nanjing Lung Cancer GWAS database to explore the association between apaQTL/eQTL-SNPs and the risk of lung adenocarcinoma (LUAD). The variant T allele of rs277646 in NIT2 is associated with an increased risk of LUAD (OR = 1.12, P = 0.015), lower PDUI values, and higher NIT2 expression. The 3'RACE experiment showed multiple poly (A) sites in NIT2, with the rs277646-T allele causing preferential use of the proximal poly (A) site, resulting in a shorter 3'UTR transcript. This leads to the loss of the hsa-miR-650 binding site, thereby affecting LUAD malignant phenotypes by regulating the expression level of NIT2. Our findings may provide new insights into understanding and exploring APA events in LUAD carcinogenesis.

Design and synthesis of new alfa-naphthoflavanones as potent and selective CYP1B1 inhibitors.

Natural Flavanones are abundant in human diet and a few of them exhibited chemopreventive effects against xenobiotic procarcinogens through the inhibition of tumour specific CYP1B1 enzyme. Herein, a series of new alfa-naphthoflavanones were synthesised and evaluated for their enzymatic inhibitory potency and selectivity of CYP1B1 over its isoenzyme CYP1A1. The most active compound 8c displayed highest inhibitory potency against CYP1B1 with the IC50 value of 0.1 nM. The structure activity relationship studies implied that the methoxy groups on the core scaffold of naphthalene ring significantly influenced CYP1B1 inhibition efficacy, while B-ring substitutions played important roles in activity. Molecular docking studies were conducted to provide a better understanding on the key structural features involved in CYP1B1 inhibitory activity. The results of the study implied that these naphthoflavanones could be considered as new leads and further investigation be conducted to explore the flavanone scaffold as skeleton for inhibiting CYP1B1.

NEDD4L mediates ITGB4 ubiquitination and degradation to suppress esophageal carcinoma progression.

The ubiquitination-mediated protein degradation exerts a vital role in the progression of multiple tumors. NEDD4L, which belongs to the E3 ubiquitin ligase NEDD4 family, is related to tumor genesis, metastasis and drug resistance. However, the anti-tumor role of NEDD4L in esophageal carcinoma, and the potential specific recognition substrate remain unclear. Based on public esophageal carcinoma database and clinical sample data, it was discovered in this study that the expression of NEDD4L in esophageal carcinoma was apparently lower than that in atypical hyperplastic esophageal tissue and esophageal squamous epithelium. Besides, patients with high expression of NEDD4L in esophageal carcinoma tissue had longer progression-free survival than those with low expression. Experiments in vivo and in vitro also verified that NEDD4L suppressed the growth and metastasis of esophageal carcinoma. Based on co-immunoprecipitation and proteome analysis, the NEDD4L ubiquitination-degraded protein ITGB4 was obtained. In terms of the mechanism, the HECT domain of NEDD4L specifically bound to the Galx-ß domain of ITGB4, which modified the K915 site of ITGB4 in an ubiquitination manner, and promoted the ubiquitination degradation of ITGB4, thus suppressing the malignant phenotype of esophageal carcinoma.

Inhibitory Effects and Mechanisms of the Novel Shikonin Derivative DMAKO-20 on Melanoma Metastasis and Invasion.

BACKGROUND: Cutaneous melanoma is a malignant tumor with an increasing incidence, prone to recurrence and metastasis. This study aims to explore the effects and mechanisms of the novel shikonin derivative 5,8-dimethyl alkannin oxime derivative (DMAKO-20) on the metastasis and invasion of melanoma cells. METHODS: The inhibitory effects of DMAKO-20 on the melanoma cell line A375 were investigated through Cell Counting Kit-8 (CCK-8), Transwell and angiogenesis experiments. Network pharmacology and Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were employed to explore potential sites and pathways involved in this process. Additionally, quantitative polymerase chain reaction (qPCR) and Western blot experiments were conducted before and after drug treatment to verify the expression trends of related pathways and proteins. RESULTS: DMAKO-20 demonstrated selective inhibition of proliferation, invasion and migration of melanoma cells at low concentrations. The WNT pathway appears to be implicated in this process, as DMAKO-20 effectively attenuates its activation, consequently reducing matrix metalloproteinase 9 (MMP9) and Cellular Communication Network Factor 1 (CCN1)/cysteine-rich angiogenic inducer 61 (CYR61) levels. Such modulation inhibits melanoma dissemination and invasion into other tissues. CONCLUSION: DMAKO-20 exhibits the capability to suppress metastasis and invasion of melanoma cells, suggesting its potential for clinical application as an adjuvant therapy against melanoma.

High-Sensitivity Differential Helmholtz Photoacoustic System Combined with the Herriott Multipass Cell and Its Application in Seed Respiration.

A highly sensitive photoacoustic detection system using a differential Helmholtz resonator (DHR) combined with a Herriott multipass cell is presented, and its implementation to sub-ppm level carbon dioxide (CO2) detection is demonstrated. Through the utilization of erbium-doped optical fiber amplifier (EDFA), the laser power was amplified to 150 mW. Within the multipass cell, a total of 22 reflections occurred, contributing to an impressive 33.6 times improvement in the system sensitivity. The normalized noise equivalent absorption coefficient (NNEA) was 8.64 × 10-11 cm-1·W·Hz-1/2 [signal-to-noise ratio, (SNR) = 1] and according to the Allan variance analysis, a minimum detection limit of 500 ppb could be achieved for CO2 at 1204 s, which demonstrates the long-term stability of the system. The system was applied to detect the respiration of rice and upland rice seeds. It is demonstrated that the system can monitor and distinguish the respiration intensity and respiration rate of different seeds in real time.

Dual-signal amplified electrochemical aptasensor based on Au/MrGO and DNA nanospheres for ultra-sensitive detection of BPA without directly modified working electrode.

Rapid and sensitive analysis of bisphenol A (BPA) is essential for preventing health risks to humans and animals. Hence, a signal-amplified electrochemical aptasensor without repetitive polishing and modification of working electrode was developed for BPA using Au-decorated magnetic reduced graphene oxide (Au/MrGO)-based recognition probe (RP) and DNA nanospheres (DNS)-based signal probe (SP) cooperative signal amplification. The DNS served as a signal molecule carrier and signal amplifier, while Au/MrGO acted as a signal amplifier and excellent medium for magnetic adsorption and separation. Moreover, utilizing the excellent magnetic properties of Au/MrGO eliminates the need for repetitive polishing and multi-step direct modification of the working electrode while ensuring that all detection processes take place in solution and that used Au/MrGO can be easily recycled. The proposed aptasensor exhibited not only good stability and selectivity, but also excellent sensitivity with a limit of detection (LOD) of 8.13 fg/mL (S/N = 3). The aptasensor's practicality was proven by spiking recovery tests on actual water samples and comparing the results with those detected by HPLC. The excellent sensitivity and selectivity make this aptasensor an alternative and promising avenue for rapid detection of BPA in environmental monitoring.

Integration of apaQTL and eQTL analysis reveals novel SNPs associated with occupational pulmonary fibrosis risk.

To explore the association between apaQTL/eQTL-SNPs and the susceptibility to silicosis. A silicosis-related GWAS was initially conducted to screen for single nucleotide polymorphisms (SNPs) associated with the risk of silicosis. Candidate SNPs with apaQTL and eQTL functions were then obtained from the 3'aQTL-atlas and GTEx databases. Subsequently, additional case-control studies were performed to validate the relationship between the candidate apaQTL/eQTL-SNPs and the risk of silicosis. Finally, experiments were conducted to illustrate APA events occurring at different alleles of the identified apaQTL/eQTL-SNPs. The combined results of the GWAS and iMLDR validations indicate that the variant T allele of the rs2974341 located on SMIM19 (additive model: OR = 0.66, the 95% CI = 0.53-0.84, P = 0.001) and the variant T allele of the rs2390488 located on TMTC4 (additive model: OR = 0.72, 95% CI = 0.57-0.90, P = 0.005) were significantly associated with decreased risk of developing silicosis susceptibility. Furthermore, 3'RACE experiments verified the presence of two poly (A) sites (proximal and distal) in SMIM19, rs2974341 may remotely regulate the binding between miRNA-3646 and SMIM19 with its high LD locus rs2974353 to affect the expression level of SMIM19. The rs2974341 variant T allele may contribute to the generation of the shorter 3'UTR transcript of SMIM19 and affect the binding of miRNA-3646 to the target gene SMIM19. The apaQTL/eQTL-SNPs may provide new perspectives for evaluating the regulatory function of SNPs in the development of silicosis.

A pH-responsive cetuximab-conjugated DMAKO-20 nano-delivery system for overcoming K-ras mutations and drug resistance in colorectal carcinoma.

Cetuximab (Cet) and oxaliplatin (OXA) are used as first-line drugs for patients with colorectal carcinoma (CRC). In fact, the heterogeneity of CRC, mainly caused by K-ras mutations and drug resistance, undermines the effectiveness of drugs. Recently, a hydrophobic prodrug, (1E,4E)-6-((S)-1-(isopentyloxy)-4-methylpent-3-en-1-yl)-5,8-dimethoxynaphthalene-1,4­dione dioxime (DMAKO-20), has been shown to undergo tumor-specific CYP1B1-catalyzed bioactivation. This process results in the production of nitric oxide and active naphthoquinone mono-oximes, which exhibit specific antitumor activity against drug-resistant CRC. In this study, a Cet-conjugated bioresponsive DMAKO-20/PCL-PEOz-targeted nanocodelivery system (DMAKO@PCL-PEOz-Cet) was constructed to address the issue of DMAKO-20 dissolution and achieve multitargeted delivery of the cargoes to different subtypes of CRC cells to overcome K-ras mutations and drug resistance in CRC. The experimental results demonstrated that DMAKO@PCL-PEOz-Cet efficiently delivered DMAKO-20 to both K-ras mutant and wild-type CRC cells by targeting the epidermal growth factor receptor (EGFR). It exhibited a higher anticancer effect than OXA in K-ras mutant cells and drug-resistant cells. Additionally, it was observed that DMAKO@PCL-PEOz-Cet reduced the expression of glutathione peroxidase 4 (GPX4) in CRC cells and significantly inhibited the growth of heterogeneous HCT-116 subcutaneous tumors and patient-derived tumor xenografts (PDX) model tumors. This work provides a new strategy for the development of safe and effective approaches for treating CRC. STATEMENT OF SIGNIFICANCE: (1) Significance: This work reports a new approach for the treatment of colorectal carcinoma (CRC) using the bioresponsible Cet-conjugated PCL-PEOz/DMAKO-20 nanodelivery system (DMAKO@PCL-PEOz-Cet) prepared with Cet and PCL-PEOz for the targeted transfer of DMAKO-20, which is an anticancer multitarget drug that can even prevent drug resistance, to wild-type and K-ras mutant CRC cells. DMAKO@PCL-PEOz-Cet, in the form of nanocrystal micelles, maintained stability in peripheral blood and efficiently transported DMAKO-20 to various subtypes of colorectal carcinoma cells, overcoming the challenges posed by K-ras mutations and drug resistance. The system's secure and effective delivery capabilities have also been confirmed in organoid and PDX models. (2) This is the first report demonstrating that this approach simultaneously overcomes the K-ras mutation and drug resistance of CRC.

Universal adhesion using mussel foot protein inspired hydrogel with dynamic interpenetration for topological entanglement.

Achieving adhesion of hydrogels to universal materials with desirable strength remains a challenge despite emerging application of hydrogels. Herein we present a mussel foot protein (Mfp) inspired polyelectrolyte hydrogel of poly(ethylenimine)/poly(acrylic acid)-dopamine (PEI/PAADA) developed for universal tough adhesion. The highly-concentrated electrostatic and hydrogen-bonding interactions in PEI/PAADA hydrogel resulted in a tensile strength, strain at break, and toughness of 0.297 MPa, 2784 % and 5.440 MJ m-3, respectively. Moreover, the hydrogel can heal itself from physical damages, even can be recycled after totally dried via rehydration because of the high flexibility and reversibility of its dynamic bonds. Combining the strategies of topological stitching and direct bonding, Mfp-derived catechol and PEI/PAA backbone in PEI/PAADA corporately facilitated robust adhesion of universal materials with shear strength of up to 4.4 MPa and peeling strength of 870 J m-2, which is over 10 times greater than that of commercial fibrin gel. The adhesive also exhibited self-healing capability for at least 5 cycles, good stability in 1 M NaCl solution and characteristic debonding catalyzed by calcium. Moreover, in vitro cell behavior and in vivo wound healing assays suggested the potential of PEI/PAADA as wound dressing.

Identification of the consistently differential expressed hub mRNAs and proteins in lung adenocarcinoma and construction of the prognostic signature: a multidimensional analysis.

BACKGROUND: This study aimed to elucidate the consistency of differentially expressed hub mRNAs and proteins in lung adenocarcinoma (LUAD) across populations and to construct a comprehensive LUAD prognostic signature. METHODS: The transcriptomic and proteomics data from different populations were standardized and analyzed using the same criteria to identify the consistently differential expressed mRNAs and proteins across genders and races. We then integrated prognosis-related mRNAs with clinical, pathological, and EGFR (epidermal growth factor receptor) mutation data to construct a survival model, subsequently validating it across populations. Through plasma proteomics, plasma proteins that consistently differential expressed with LUAD tissues were screened and validated, with their associations discerned by measuring expressions in tumor tissues and tumor vascular normalization. RESULTS: The consistency rate of differentially expressed mRNAs and proteins was ~20-40%, with ethnic factors leading to about 40-60% consistency of differentially expressed mRNA or protein across populations. The survival model based on the identified eight hub mRNAs as well as stage, smoking status, and EGFR mutations, demonstrated good prognostic prediction capabilities in both Western and East Asian populations, with a higher number of unfavorable variables indicating poorer LUAD prognosis. Notably, GPI expression in tumor tissues was inversely correlated with vascular normalization and positively correlated with plasma GPI expression. CONCLUSION: Our study underscores the significance of integrating transcriptomics and proteomics data, emphasizing the need to account for genetic diversity among ethnic groups. The developed survival model may offer a holistic perspective on LUAD progression, enhancing prognosis and therapeutic strategies.

A cytotoxicity and mechanistic investigation of mono- and di-chloro naphthalenes.

Polychlorinated naphthalenes (PCNs) were characterized as persistent organic pollutants (POPs) that were widely distributed in the environment. Although the striking in vivo toxicity of these pollutants towards both animals and humans was well documented, their cytotoxicity and mechanism of action have not been extensively investigated. In this study, the in vitro antiproliferative activity of mono- and di-chloronaphthalenes as representative PCNs were evaluated and the results indicated strong growth inhibitory effects against mammalian cells, especially the human breast MCF-10A cell and human hepatic HL-7702 cells. 2-Chloronaphthalene with the most potent antiproliferative effects within the tested PCNs, which showed IC50 values ranging from 0.3 mM to 1.5 mM against selected human cell lines, was investigated for its working mechanisms. It promoted cellular apoptosis of MCF-10A cells upon the concentration of 200 µM. It also induced the autophagy of MCF-10A cells in a dose-dependent manner, resulting in cell death via the interaction of autophagy and apoptosis. Thus, these findings supported the theoretical foundation for interventional treatment of PCNs toxicity and also provided implications for the use of chemopreventive agents against the toxic chlorinated naphthalenes in the environments.

The potential health effects associated with electronic-cigarette.

A good old gateway theory that electronic-cigarettes (e-cigarettes) are widely recognized as safer tobacco substitutes. In actuality, demographics also show that vaping cannibalizes smoking, the best explanation of the data is the "common liability". However, the utilization of e-cigarette products remains a controversial topic at present. Currently, there has been a widespread and substantial growth in e-cigarette use worldwide owing to their endless new flavors and customizable characteristics. Furthermore, e-cigarette has grown widespread among smokers as well as non-smokers, including adolescents and young adults. And some studies have shown that e-cigarette users are at greater risk to start using combustible cigarettes while e-cigarettes use was also observed the potential benefits to people who want to quit smoking or not. Although it is true that e-cigarettes generally contain fewer toxic substances than combustible cigarettes, this does not mean that the chemical composition in e-cigarettes aerosols poses absolutely no risks. While concerns about toxic substances in e-cigarettes and their widespread use in the population are reasonable, it is also crucial to consider that e-cigarettes have been associated with the potential for promoting smoking cessation and the clinically relevant improvements in users with smoking-related pathologies. Meanwhile, there is still short of understanding of the health impacts associated with e-cigarette use. Therefore, in this review, we discussed the health impacts of e-cigarette exposure on oral, nasal, pulmonary, cardiovascular systems and brain. We aspire for this review to change people's previous perceptions of e-cigarettes and provide them with a more balanced perspective. Additionally, we suggest appropriate adjustments on regulation and policy for e-cigarette to gain greater public health benefits.

Mechanically Reinforced and Injectable Universal Adhesive Based on a PEI-PAA/Alg Dual-Network Hydrogel Designed by Topological Entanglement and Catechol Chemistry.

Universal adhesion of hydrogels to diverse materials is essential to their extensive applications. Unfortunately, tough adhesion of wet surfaces remains an urgent challenge so far, requiring robust cohesion strength for effective stress dissipation. In this work, a dual-network hydrogel polyethylenimine-poly(acrylic acid)/alginate (PEI-PAA/Alg) with excellent mechanical strength is realized via PEI-PAA complex and calcium alginate coordination for universal adhesion by the synergistic effort of topological entanglement and catechol chemistry. The dual networks of PEI-PAA/Alg provide mechanically reinforced cohesion strength, which is sufficient for energy dissipation during adhesion with universal materials. After the integration of mussel-inspired dopamine into PAA or Alg, the adhesive demonstrates further improved adhesion performance with a solid adherend and capability to bond cancellous bones. Notably, the dopamine-modified adhesive exhibits better instant adhesion and reversibility with wet surfaces compared with commercial fibrin. Adhesion interfaces are investigated by SEM and micro-FTIR to verify the effectiveness of strategies of topological entanglement. Furthermore, the adhesive also possesses great injectability, stability, tissue adhesion, and biocompatibility. In vivo wound healing and histological analysis indicate that the hydrogel can promote wound closure, epidermis regeneration, and tissue refunctionalization, implying its potential application for bioadhesive and wound dressing.

Design and Synthesis of Novel Near-Infrared Fluorescence Probes Based on an Open Conformation of a Cytochrome P450 1B1 Complex for Molecular Imaging of Colorectal Tumors.

Cytochrome P450 1B1 (CYP1B1) is induced during the early stage of cancer and is universally overexpressed in tumors. Thus, it was considered as a potential biomarker for the monitoring of cancer. In this study, we designed and synthesized CYP1B1-targeted near-infrared (NIR) fluorescence molecular probes based on the latest reported open conformation of the CYP1B1-α-naphthoflavone (ANF) complex. According to the architecture of the open channel, we introduced linkers and a Cy5.5 fragment at the 5' position of ANF derivatives with strong CYP1B1 inhibitory activity to obtain probes 19-21. Then, in vitro cell-based studies showed that the probes could be enriched in tumor cells by binding to CYP1B1. During in vivo and ex vivo imaging in a xenograft mouse model, probe 19 with the best binding affinity was proven to be able to identify tumor sites in both fluorescence imaging and photoacoustic imaging modes.

A novel APA-based prognostic signature may predict the prognosis of lung adenocarcinoma in an East Asian population.

The role of alternative polyadenylation (APA) in tumor development is becoming increasingly evident, but the impact of APA events on the prognosis of LUAD patients is unclear. Therefore, in the present study, we aimed to analyze specific APA events in LUAD to identify novel prognostic biomarkers for LUAD. We first identified prognostic candidate genes for LUAD associated with APA events and validated them in both the East Asian and the USA cohorts, finding that five genes (DCUN1D5, PSMC4, TFAM, THRA, and TMEM100) were of prognostic significance in both populations. Based on this, an APA-based prognostic signature was constructed for the East Asian population. The predictive accuracy of the prognostic signature was further evaluated by the time-dependent ROC, with 1-, 2-, and 3-year AUCs of 0.86, 0.81, and 0.71, respectively. This study may provide new markers for individualized diagnosis and prognostic assessment of LUAD and potential targets for precision treatment.

In vitro metabolism of triclosan and chemoprevention against its cytotoxicity.

Triclosan (TCS), a broad-spectrum antibacterial chemical, has been extensively used in personal daily care items, household commodities, and clinical medications; therefore, humans are at risk of being exposed to TCS in their daily lives. This chemical also accumulated in food chains, and potential risks were associated with its metabolism in vivo. The aim of this study was to investigate the difference in metabolic profile of TCS by hepatic P450 enzymes and extrahepatic P450s, and also identify chemical structures of its metabolites. The results showed that RLM mediated the hydroxylation and cleavage of the ether moiety of TCS, resulting in phenolic metabolites that are more polar than the parent compound, including 4-chlorocatechol, 2,4-dichlorophenol and monohydroxylated triclosan. The major metabolite of CYP1A1 and CYP1B1 mediated TCS metabolism is 4-chlorochol. We also performed molecular docking experiments to investigate possible binding modes of TCS in the active sites of human CYP1B1, CYP1A1, and CYP3A4. In addition to in vitro experiments, we further examined the cytotoxic effects of TCS on HepG2 cells expressing hepatic P450 and MCF-7/1B1 cells expressing CYP1B1. It exhibited significant cytotoxicity on HepG2, MCF-10A and MCF-7/1B1 cells, with IC50 values of 70 ± 10 µM, 20 ± 10 µM and 60 ± 20 µM, respectively. The co-incubation of TCS with glutathione (GSH) as a chemopreventive agent could reduce the cytotoxicity of TCS in vitro. The chemopreventive effects of GSH might be ascribed to the promotion of TCS efflux mediated by membrane transporter MRP1 and also its antioxidant property, which partially neutralized the oxidative stress of TCS on mammalian cells. This study contributed to our understanding of the relationship between the P450 metabolism and the toxicity of TCS. It also had implications for the use of specific chemopreventive agents against the toxicity of TCS.

Discovery of Dimethyl Shikonin Oxime 5a, a Potent, Selective Bombesin Receptor Subtype-3 Agonist for the Treatment of Type 2 Diabetes Mellitus.

Bombesin receptor subtype-3 (BB3, BRS-3) is an orphan Gαq protein-coupled receptor. The characterization of novel synthetic ligands for BB3 is an alternative and attractive strategy to study its diverse physiological functions. Here, we uncovered the intimate pairing of DMAKO-00 and its derivatives with BB3. Dimethyl shikonin oxime 5a (DSO-5a) was identified as the most potent agonist for BB3 (pEC50 = 8.422 in IP-1 accumulation), which was 898-fold more potent than DMAKO-00. Importantly, without brain penetration, DSO-5a improved glucose tolerance in C57BL/6 mice through BB3 and ameliorated glucose homeostasis in diabetic db/db mice. We further revealed that DSO-5a upregulated PPAR-gamma activity via BB3 through a quantitative proteomics approach. Collectively, our study demonstrated that DSO-5a, a representative compound of DMAKO-00 derivatives, is a potent, selective, and low-brain-penetrating agonist for BB3, and BB3 is a promising treatment target for type 2 diabetes mellitus.