Huang Qin decoction increases SLC6A4 expression and blocks the NFκB-mediated NLRP3/Caspase1/GSDMD pathway to disrupt colitis-associated carcinogenesis.

Huang Qin decoction (HQD) is a traditional Chinese medicine formula for treating colitis, but the effects and molecular mechanism of action of HQD in colitis-associated carcinogenesis (CAC) are still unclear. Therefore, we aimed to determine the beneficial effects of HQD on CAC in mice and to reveal the underlying mechanism involved. AOM/DSS was used to induce CAC in mice, and the effects of HQD on tumorigenesis in mice were examined (with mesalazine serving as a positive control). Mesalazine or HQD treatment alleviated body weight loss and decreased the disease activity index in mice induced by AOM/DSS. Mesalazine or HQD treatment also suppressed the shortening of colon tissue length, the number of tumors, and the infiltration of inflammatory cells. The genes targeted by HQD were predicted and verified, followed by knockout experiments. Elevated SLC6A4 and inhibited serotonin production and inflammation were observed in HQD-treated mice. HQD inhibited the NFκB and NLRP3/caspase1/GSDMD pathways. The therapeutic effect of HQD was diminished in SLC6A4-deficient AOM/DSS mice. Additionally, the downregulation of SLC6A4 mitigated the inhibitory effect of HQD-containing serum on MODE-K cell pyroptosis. Our findings suggest that SLC6A4 is a pivotal regulator of HQD-alleviated CAC via its modulation of the NLRP3/caspase1/GSDMD pathway.

Integrated oral microgel system ameliorates renal fibrosis by hitchhiking co-delivery and targeted gut flora modulation.

BACKGROUND: Renal fibrosis is a progressive process associated with chronic kidney disease (CKD), contributing to impaired kidney function. Active constituents in traditional Chinese herbs, such as emodin (EMO) and asiatic acid (AA), exhibit potent anti-fibrotic properties. However, the oral administration of EMO and AA results in low bioavailability and limited kidney accumulation. Additionally, while oral probiotics have been accepted for CKD treatment through gut microbiota modulation, a significant challenge lies in ensuring their viability upon administration. Therefore, our study aims to address both renal fibrosis and gut microbiota imbalance through innovative co-delivery strategies. RESULTS: In this study, we developed yeast cell wall particles (YCWPs) encapsulating EMO and AA self-assembled nanoparticles (NPYs) and embedded them, along with Lactobacillus casei Zhang, in chitosan/sodium alginate (CS/SA) microgels. The developed microgels showed significant controlled release properties for the loaded NPYs and prolonged the retention time of Lactobacillus casei Zhang (L. casei Zhang) in the intestine. Furthermore, in vivo biodistribution showed that the microgel-carried NPYs significantly accumulated in the obstructed kidneys of rats, thereby substantially increasing the accumulation of EMO and AA in the impaired kidneys. More importantly, through hitchhiking delivery based on yeast cell wall and positive modulation of gut microbiota, our microgels with this synergistic strategy of therapeutic and modulatory interactions could regulate the TGF-ß/Smad signaling pathway and thus effectively ameliorate renal fibrosis in unilateral ureteral obstruction (UUO) rats. CONCLUSION: In conclusion, our work provides a new strategy for the treatment of renal fibrosis based on hitchhiking co-delivery of nanodrugs and probiotics to achieve synergistic effects of disease treatment and targeted gut flora modulation.

Predictors of vein graft disease progression between one week and one year after surgical coronary revascularization: Impact of secondary prevention medications.

OBJECTIVE: This study aimed to detect the predictors of vein graft disease (VGD) progression between 1 week and 1 year after surgery and to evaluate the impact of secondary prevention medications. METHODS: A total of 218 consecutive patients underwent surgical coronary revascularization were evaluated by coronary computed tomography angiography both at 1-week and 1-year follow-up. Logistic regression analyses were performed to investigate the predictors of VGD progression. A risk score (0-4) was set up to evaluate implementation result of secondary prevention measures according to 1-year follow-up result. Association between VGD progression and the risk score was assessed. RESULTS: VGD progression occurred in 11.3% of saphenous vein grafts (SVG) and 22.1% of patients. At the patient level, poor vein graft (odds ratio [OR] = 4.25), noncontrolled hyperlipidemia (OR = 3.01), and diabetes mellitus (DM) (OR = 2.96) were predictors, while diameter of SVG (mm, OR = 0.35) was protective factor. At the graft level, DM (OR = 3.52), noncontrolled hyperlipidemia (OR = 2.33), and peripheral artery disease (PAD) (OR = 2.20) were predictors, while number of SVGs (OR = 0.63), diameter of SVG (mm, OR = 0.39), and mean graft flow >25 ml/min (OR = 0.35) were protective factors. VGD progression was significantly associated with the risk score at both the patient (OR = 1.52) and the graft level (OR = 1.38). CONCLUSIONS: Poor vein graft, noncontrolled hyperlipidemia and DM were predictors of VGD progression between 1 week and 1 year after surgery at the patient level, while larger SVG diameter was a protective factor. DM, PAD and noncontrolled hyperlipidemia were predictors at the graft level, while a number of SVGs, larger SVG diameter, and mean graft flow >25 ml/min were protective factors. Implementation failure of secondary prevention medications was associated with VGD progression from as early as 1 year after surgery.

LH upregulates connexin 43 expression in granulosa cells by activating the Wnt/ß-catenin signalling pathway.

Connexin (Cx) 43 is the most widely expressed gap junction protein in follicle granulosa cells and plays an important role in follicle development and growth. The aims of this study were to investigate the effects of LH on the expression of Cx43 and key proteins in the downstream Wnt-ß/catenin signalling pathway and to explore the mechanism underlying the regulation of Cx43 expression in granulosa cells. Primary culture granulosa cells were obtained from 21-day-old Sprague-Dawley rats, and were treated with different concentrations of LH (150, 300 and 600 IU L-1). Cx43 expression in granulosa cells was detected using immunofluorescence. Western blotting was used to detect the expression of Cx43, ß-catenin and Axin2 proteins (Axin2 is a protein that in humans is encoded by the AXIN2 gene, which presumably plays an important role in the regulation of the stability of ß-catenin in the Wnt signaling pathway) in granulosa cells with and without FH535 treatment (a Wnt/ß-catenin signalling pathway inhibitor). Cx43 expression was detected in the cytoplasm and cell membrane of granulosa cells. Treatment with a high concentration of LH (300 IU L-1) increased the expression of ß-catenin and Axin2, as well as that of Cx43. FH535 treatment reduced the LH-induced increases in Cx43, ß-catenin and Axin2. These results indicate that LH upregulates Cx43 expression in granular cells by activating the Wnt/ß-catenin signalling pathway.

A Case-Control Study on the Therapeutic Effect of Mediastinoscope-Assisted and Thoracoscope-Assisted Esophagectomy.

Objective. To compare the clinical efficacies of mediastinoscope-assisted and thoracoscope-assisted esophagectomy. Materials and Methods. Seventy-six patients with esophageal cancer who underwent minimally invasive esophagectomy at the General Hospital of Ningxia Medical University between June 2015 and January 2019 were retrospectively evaluated. Among them, 28 patients underwent mediastinoscope-assisted transhiatal esophagectomy (MATHE), and 48 received thoracoscope-assisted transthoracic esophagectomy (TATTE). The perioperative clinical data and follow-up data of the 2 groups were compared. Results. All operations were successful in both groups. MATHE was favorable in terms of operation time, intraoperative blood loss, drainage volume 3 days after surgery, postoperative hospital stay, and hypoproteinemia (P < .05). Lymph node dissections were less than those in the TATTE (P < .05). No significant differences in long-term postoperative complications and survival rate were found between the 2 groups (P > .05). Conclusion. MATHE has the advantages of minimal trauma, shorter operation time, less intraoperative blood loss, and faster recovery. More adequate tumor clearance in terms of lymph node dissection can be achieved with TATTE. However, the comparison of survival rates between the 2 groups is similar.

Long-term outcome of a Chinese cohort idiopathic retinitis, vasculitis, aneurysms, and neuroretinits (IRVAN) patients.

PURPOSE: To evaluate the clinical characteristics and treatment outcomes of idiopathic retinitis, vasculitis, aneurysms, and neuroretinitis (IRVAN) in a cohort of Chinese patients. MATERIALS: The clinical history, imaging evaluation, treatment and outcomes of 42 eyes in 21 patients diagnosed with IRVAN in a 15-year period were reviewed. RESULTS: Most patients were females (90%) ranged from 15 to 58 years old. The initial decimal best corrected visual acuity (BCVA) of the patients ranged from light perception (LP) to 1.5 (0.55 ± 0.38). Eighteen eyes were in stage 2; 21 eyes in stage 3; and 1 in stage 5 at the initial visits according to the present staging system. Two eyes had vitreoretinal fibrovascular proliferation (FVP) and tractional retinal detachment (RD) at the initial visit. Intra-retinal microvascular abnormality (IRMA) was found in 7 eyes. Thirty-four eyes received retinal photocoagulation, 27 of which were pan-retinal photocoagulation (PRP). Total of 8 PPV were performed for VH, vitreoretinal FVP and RD, and macular epimembrane. Aneurysms on the head of optic nerve and artery bifurcations disappeared in 8 eyes and decreased in number in 2 eyes 1 year after photocoagulation. However, the BCVA of the patients did not have significant difference from that at the initial visits (P = 0.534). Seven eyes suffered severe visual impairment (BCVA ≤ 0.1) due to vitreoretinal FVP and tractional RD (3), exudative maculopathy (2), paracentral acute middle maculopathy (PAMM)(1), and neovascular glaucoma (NVG) (1). CONCLUSIONS: We found that IRVAN have a predilection to female gender. Vitreoretinal FVP and tractional RD and exudative maculopathy are major causes of severe visual impairment in IRVAN patients. We propose to revise the present staging system to include vitreoretinal FVP and RD in the staging of IRVAN patients.

Ultrasound and Magnetic Responsive Drug Delivery Systems for Cardiovascular Application.

With the increasing insight into molecular mechanisms of cardiovascular disease, a promising solution involves directly delivering genes, cells, and chemicals to the infarcted myocardium or impaired endothelium. However, the limited delivery efficiency after administration fails to reach the therapeutic dose and the adverse off-target effect even causes serious safety concerns. Controlled drug release via external stimuli seems to be a promising method to overcome the drawbacks of conventional drug delivery systems (DDSs). Microbubbles and magnetic nanoparticles responding to ultrasound and magnetic fields respectively have been developed as an important component of novel DDSs. In particular, several attempts have also been made for the design and fabrication of dual-responsive DDS. This review presents the recent advances in the ultrasound and magnetic fields responsive DDSs in cardiovascular application, followed by their current problems and future reformation.

Serum triglycerides as a risk factor for cardiovascular diseases in type 2 diabetes mellitus: a systematic review and meta-analysis of prospective studies.

OBJECTIVE: The importance of triglycerides (TG) level as a risk factor for cardiovascular diseases (CVD) has been extensively investigated in the general population; however, their relationship in patients with type 2 diabetes mellitus (T2DM) is uncertain. We aimed to assess the association of TG with CVD in T2DM individuals. RESEARCH DESIGN AND METHODS: We searched bibliographic databases for studies published until June 2018, reporting on the relationship between TG and CVD in T2DM people. A random-effects model with inverse variance weighting was used to compute pooled estimates of the most fully adjusted risk ratios (RR) and corresponding 95% confidence intervals (CI) according to TG categories, unit TG, and logarithm (log) of TG for CVD. RESULTS: A total of 31 studies were included, involving 132,044 T2DM patients with 10,733 incident cardiovascular events. The pooled RR (95% CI) of CVD for an increase in baseline TG, log TG by 1-mmol/l and categorized in the highest vs. the lowest TG in T2DM were 1.06 (1.02, 1.09), 1.30 (1.18, 1.42) and 1.30 (1.16, 1.46), corresponding to a CVD risk increase of 6%, 30% and 30%, respectively. The pooled RR (95% CI) of CVD for per 1-mmol/L TG increment in eight studies and TG categories in three studies were 1.03 (0.98, 1.08) and 1.39 (0.92, 2.1) in T2DM patients adjusted for other lipids parameter, respectively. CONCLUSIONS: In T2DM patients, an elevated triglyceride level cannot serve as an independent marker for an increased risk of cardiovascular events, but still, the higher serum TG levels tend to be associated with increased risks of CVD.

NOVEL BEST1 MUTATIONS DETECTED BY NEXT-GENERATION SEQUENCING IN A CHINESE POPULATION WITH VITELLIFORM MACULAR DYSTROPHY.

PURPOSE: To characterize novel BEST1 mutations and the phenotype-genotype correlations in vitelliform macular dystrophy in a Chinese population. METHODS: Seventeen individuals affected by vitelliform macular dystrophy underwent detailed ophthalmic examinations, including a best-corrected visual acuity test, slit-lamp biomicroscopy, fundus photography, spectral-domain optical coherence tomography, fundus autofluorescence, fluorescein angiography, and optical coherence tomography angiography. Next-generation sequencing was used to screen 790 genes frequently involved in common inherited nonsyndromic eye diseases in all participants. Sanger sequencing was used to identify possible disease-causing variants. RESULTS: The mean ± SD age of the patients was 44.20 ± 15.09 (range: 16-69) years. Seven novel BEST1 mutations were identified: six heterozygous missense (p.Thr307Asn, p.Ile295The, p.Leu75Pro, p.Thr2Ser, p.Ser79Tyr, and p.Val81Leu) and one frameshift (p.Glu115GlufsX120) mutation. Choroidal neovascularization was detected in two probands. One individual presented with subfoveal focal choroidal excavation. Arden ratios obtained by electrooculography were less than the 1.5 cutoff value in 7 patients. No mutations were identified in 2 patients, one of whom had a fundus appearance typical of vitelliform macular dystrophy and a decreased Arden ratio (1.2/1.2). CONCLUSION: Patients with the same heterozygous BEST1 mutations exhibited varying phenotypes. Our results have expanded the BEST1 mutation spectrum in a Chinese population with vitelliform macular dystrophy.

The relationship between foveal outer nuclear layer thickness in the active and resolved phases of central serous chorioretinopathy treated with half-dose photodynamic therapy.

BACKGROUND: To investigate the relationship between the foveal outer nuclear layer (ONL) thickness in the active and resolved phases of central serous chorioretinopathy (CSC), and its possible association with optical coherence tomography (OCT) parameters. METHODS: The medical records of CSC patients treated with half-dose photodynamic therapy (PDT) between August 2011 and October 2017 were reviewed. The difference between the foveal ONL thickness at 12 m after half-dose PDT and that before half-dose PDT was analyzed, and its association with OCT parameters was assessed using generalized linear models. RESULTS: Sixty-two patients were included. The mean difference in foveal ONL thickness was 9.15 ± 8.16 µm. The average ratios of the retinal detachment height to the subretinal space width on horizontal and vertical scans were 0.10 ± 0.04 and 0.12 ± 0.04, respectively. The ratio was independently associated with the degree of increase in the foveal ONL thickness difference on both the horizontal scans (ß = 103.684, P = .000) and vertical scans (ß = 67.569, P = .000), even after adjusting for potential confounders. CONCLUSIONS: The majority of resolved CSC eyes showed some increase in foveal ONL thickness, and the degree of increase was related to the ratio of the retinal detachment height to the subretinal space width in their active phase. It suggested that the retina is stretched when it becomes detached, and recovers with resolution of the subretinal fluid. Therefore, besides photoreceptor cell death, retinal stretch may contribute to the reduction in foveal ONL thickness in eyes with active CSC.

MULTIMODAL FUNDUS IMAGING OF OUTER RETINAL TUBULATIONS IN CHOROIDAL OSTEOMA PATIENTS.

PURPOSE: To evaluate the morphological findings of outer retinal tubulations (ORTs) shown on multimodal imaging modalities in patients with choroidal osteoma. METHODS: Nineteen eyes of 17 patients with choroidal osteoma underwent full clinical and imaging assessments. Color fundus photography, spectral-domain optical coherence tomography (OCT), and en face OCT were used to identify and detect the characteristics of ORT structures, including the shape, configuration, location, and distribution in the fundus. Optical coherence tomography angiography was implemented as an assist to differentiate tumor's feeder vessels from choroidal neovascularization. The correlations between age, gender, tumor features, best-corrected visual acuity at baseline, OCT characteristics, and the presence of ORTs were analyzed. RESULTS: Outer retinal tubulations were identified in five eyes (26.3%). All were located at the decalcified region of the tumor where the choroidal vessels, retinal pigment epithelium, and overlying outer retinal structures were considerably disrupted to varying degrees. With spectral-domain OCT, the ORTs appeared as one or multiple, round or ovoid, hyporeflective lumens with hyperreflective borders confined to the outer nuclear layer, sometimes with hyperreflective luminal content (four eyes, 80%). In one eye, ORTs were found at the focal choroidal excavation. On en face OCT, these tubulations exhibited different shapes, including a dendritic pattern in two eyes, a tube-like pattern in one eye, a circular pattern in one eye, and a hairpin pattern in one eye. Simultaneous OCT angiography imaging demonstrated that the area of choroidal neovascularization was underneath ORT in one eye and very close to ORT in two eyes. The ORTs of three eyes were above or adjacent to tumor's rich feeder vessels. Statistically, age (P = 0.007), greatest tumor linear dimension (P = 0.003), total tumor area (P = 0.002), decalcification area (P = 0.000), and the presence of intraretinal fluid (P = 0.01) and retinal pigment epithelium alterations (P = 0.038) within the foveola and central 1-mm region of patients with ORT were significantly different from those of patients without ORTs. CONCLUSION: The results of this study suggest that age, the greatest tumor linear dimension, total tumor area, decalcification area, and the presence of intraretinal fluid and retinal pigment epithelium alterations within the foveola and central 1-mm region might be risk factors for ORT formation. Spectral-domain OCT combined with en face OCT provides comprehensive imaging information for ORTs in choroidal osteoma.

Predictive multi-imaging biomarkers relevant for visual acuity in idiopathic macular telangiectasis type 1.

BACKGROUND: To evaluate the structural changes associated with visual acuity (VA) in patients with idiopathic macular telangiectasia (MT) type 1 using multimodal imaging modalities. METHODS: A retrospective study of 14 patients with MT type 1 and of 10 eyes from 10 healthy individuals as age-matched controls was conducted. The medical records of patients who had undergone colour fundus photography, spectral domain optical coherence tomography (OCT), fluorescein angiography and OCT angiography were reviewed. Central macular thickness (CMT), the areas of macular oedema and ellipsoid zone (EZ) disruption, EZ length, disorganization of the retinal inner layers (DRIL) and external limiting membrane (ELM) disruption, as measured by spectral domain OCT; and vascular density and the foveal avascular zones (FAZ) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP), as measured by OCT angiography, were assessed in MT type 1 eyes and correlated with VA. RESULTS: The mean baseline best-corrected VA of MT type 1 eyes was 0.45 ± 0.28. The mean CMT was 385.19 ± 75.21 µm in MT type 1 eyes and 252.43 ± 15.77 µm in contralateral eyes (Z = - 4.113, p < 0.001). The mean vessel density of the DCP was lower in MT type 1 eyes (47.25 ± 4.69%) than in contralateral eyes (53.93 ± 2.94%) and normal eyes (59.37 ± 2.50%) (Z = - 3.492, - 4.099; p < 0.001, < 0.001). The baseline logMAR VA was correlated with CMT (r = 0.682, p = 0.007), SCP density (r = - 0.652, p = 0.012), DCP density (r = - 0.700, p = 0.005), total area of EZ disruption (r = 0.649, p = 0.012); and total lengths of EZ (r = 0.681, p = 0.007), ELM (r = 0.699, p = 0.005) and DRIL (r = 0.707, p = 0.005) disruption in the 1-mm-diameter foveal region in MT type 1 eyes. CONCLUSIONS: Decreased DCP density and the presence of DRIL may be predictive biomarkers of VA in MT type 1. CMT, SCP density, total area of EZ disruption, and lengths of EZ and ELM disruption within the 1-mm-diameter central region were strongly associated with VA.

Successful Surgical Treatment of Descending Aorta Interruption: A Case Report.

Descending aorta interruption is an extremely rare congenital defect. Conventional repair with end-to-end anastomoses is often a surgical challenge in view of the extensive collateral vessels that develop on the chest wall and inside the chest cavity. Extra-anatomic bypass is the preferred technique for the surgical repair of this entity, which avoids the network of collateral vessels, enables simultaneous treatment of associated lesions, and in all likelihood reduces morbidity and mortality. Here we describe an extra-anatomic bypass from the ascending aorta to the bilateral iliac arteries in a 24-year-old woman using vascular grafts (MAQUET Holding B.V. & Co. KG, Rastatt, Germany) without cardiopulmonary bypass.

Ferric iron and extracellular electron shuttling increase xylose utilization and butanol production during fermentation with multiple solventogenic bacteria.

Xylose is the second most abundant sugar derived from lignocellulose; it is considered less desirable than glucose for fermentation, and strategies that specifically increase xylose utilization in wild-type cells are goals for biofuel production. Xylose consumption, butanol production, and hydrogen production increased in both Clostridium beijerinckii and a novel solventogenic bacterium (strain DC-1) when anthraquinone-2,6,-disulfonate (AQDS) or riboflavin were used as redox mediators to transfer electrons to poorly crystalline Fe(OH)3 as an extracellular electron sink. Strain DC-1 was most closely related to Rhizobiales bacterium Mfc52 based on 95% 16S rRNA gene sequence similarity, which demonstrates that this response is not limited to a single genus of xylose-fermenting bacteria. Xylose utilization and butanol production were negligible in control incubations containing cells plus 3% (w/v) xylose alone during a 10-day batch fermentation, for both strains tested (n-butanol titers of 0.05 g L-1). Micromolar concentrations of AQDS and riboflavin were added as electron shuttling compounds with poorly crystalline Fe(OH)3 as an insoluble electron acceptor, and respective n-butanol titers increased to 6.35 and 7.46 g L-1. Increases in xylose consumption for the iron treatments were relatively high, from less than 0.49 g L-1 (xylose alone, no iron or electron shuttling molecules) to 25.98 and 29.15 g L-1 for the AQDS and riboflavin treatments, respectively. Hydrogen production was also 3.68 times greater for the AQDS treatment and 5.27 greater for the riboflavin treatment relative to controls. Strain DC-1 data were similar, again indicating that the effects are not specific to the genus Clostridium.

[Advances in quorum-sensing LuxR solos in bacteria].

Quorum-sensing (QS) involved in the production of N-Acylhomoserine lactones (AHLs) is a universal way of communication of gram-negative bacteria. Complete AHL-QS system includes pairs of AHLs synthase belonging to LuxI family and cognate LuxR-family AHLs sensor-regulator. However, many gram-negative bacteria have evidenced the presence of AHL-QS related LuxR-type genes, which are unpaired to a cognate LuxI. These unpaired LuxRs have been called solos or orphans. LuxR solos are thought to be important for bacterial signal perception in eavesdropping, intra-species and inter-kingdom communication, which become research topic in the field of QS. Here, the finding, concept, protein structure, and main types of LuxR solos are illustrated. Furthermore, the function and important protein of LuxR solos associated with sensing AHLs or non-AHLs are reviewed. The prospect and significance of quorum sensing LuxR solos in bacteria are also discussed.

Impact of decellularization on porcine myocardium as scaffold for tissue engineered heart tissue.

Decellularized myocardium has been proposed to construct tissue engineered heart tissue, providing the advantage of natural extracellular architecture. Various decellularization protocols have been developed, but the impact of individual decellularization reagent in the protocol remains unclear. The aim of this study is to evaluate the structural impact of three commonly used decellularization reagents on the porcine myocardium. We decellularized porcine heart tissue with trypsin, Triton X-100 or SDS, and analyzed the morphological characteristics of the remaining tissue by SEM, AFM and two-photon LSM. We further recellularized the scaffold with rat myocardial fibroblasts and cardiomyocytes separately. According to the H&E staining and DNA quantification, SDS decellularized more efficiently in comparison to the other two reagents. Moreover, we found distinct surface microarchitecture differences among groups. The changed structure of tissue might result in varied proliferation myocardial fibroblasts and biophysical performance of the engineered heart tissue. This study demonstrated that the microstructure of decellularized porcine heart tissue vary with decellularization agents. Compared to trypsin and Triton X-100, SDS not only decellularized more efficiently but also preserved the biocompatible microstructure of ECM for recellularization.

EGFR phosphorylates and inhibits lung tumor suppressor GPRC5A in lung cancer.

BACKGROUND: GPRC5A is a retinoic acid inducible gene that is preferentially expressed in lung tissue. Gprc5a- knockout mice develop spontaneous lung cancer, indicating Gprc5a is a lung tumor suppressor gene. GPRC5A expression is frequently suppressed in majority of non-small cell lung cancers (NSCLCs), however, elevated GPRC5A is still observed in a small portion of NSCLC cell lines and tumors, suggesting that the tumor suppressive function of GPRC5A is inhibited in these tumors by an unknown mechanism. METHODS: In this study, we examined EGF receptor (EGFR)-mediated interaction and tyrosine phosphorylation of GPRC5A by immunoprecipitation (IP)-Westernblot. Tyrosine phosphorylation of GPRC5A by EGFR was systematically identified by site-directed mutagenesis. Cell proliferation, migration, and anchorage-independent growth of NSCLC cell lines stably transfected with wild-type GPRC5A and mutants defective in tyrosine phosphorylation were assayed. Immunohistochemical (IHC) staining analysis with specific antibodies was performed to measure the total and phosphorylated GPRC5A in both normal lung and lung tumor tissues. RESULT: We found that EGFR interacted with GPRC5A and phosphorylated it in two conserved double-tyrosine motifs, Y317/Y320 and Y347/ Y350, at the C-terminal tail of GPRC5A. EGF induced phosphorylation of GPRC5A, which disrupted GPRC5A-mediated suppression on anchorage-independent growth of NSCLC cells. On contrary, GPRC5A-4 F, in which the four tyrosine residues have been replaced with phenylalanine, was resistant to EGF-induced phosphorylation and maintained tumor suppressive activities. Importantly, IHC analysis with anti-Y317/Y320-P sites showed that GPRC5A was non-phosphorylated in normal lung tissue whereas it was highly tyrosine-phosphorylated in NSCLC tissues. CONCLUSION: GPRC5A can be inactivated by receptor tyrosine kinase via tyrosine phosphorylation. Thus, targeting EGFR can restore the tumor suppressive functions of GPRC5A in lung cancer.

The SNAG domain of Snail1 functions as a molecular hook for recruiting lysine-specific demethylase 1.

Epithelial-mesenchymal transition (EMT) is a transdifferentiation programme. The mechanism underlying the epigenetic regulation of EMT remains unclear. In this study, we identified that Snail1 interacted with histone lysine-specific demethylase 1 (LSD1). We demonstrated that the SNAG domain of Snail1 and the amine oxidase domain of LSD1 were required for their mutual interaction. Interestingly, the sequence of the SNAG domain is similar to that of the histone H3 tail, and the interaction of Snail1 with LSD1 can be blocked by LSD1 enzymatic inhibitors and a histone H3 peptide. We found that the formation of a Snail1-LSD1-CoREST ternary complex was critical for the stability and function of these proteins. The co-expression of these molecules was found in cancer cell lines and breast tumour specimens. Furthermore, we showed that the SNAG domain of Snail1 was critical for recruiting LSD1 to its target gene promoters and resulted in suppression of cell migration and invasion. Our study suggests that the SNAG domain of Snail1 resembles a histone H3-like structure and functions as a molecular hook for recruiting LSD1 to repress gene expression in metastasis.