Valsartan reduces AT1-AA-induced apoptosis through suppression oxidative stress mediated ER stress in endothelial progenitor cells

OBJECTIVE

Valsartan has been reported to have the function of treating hypertension and improving the prognosis of patients. Many studies indicated that valsartan can also increase angiotensin II, andosterone and plasma renin activity (PRA). Autoantibodies against the angiotensin II type 1 receptor (AT1-AA) have been showed to increase reactive oxygen species (ROS) and calcium (Ca2+) and result in apoptosis in vascular smooth muscle cells. In this study, we attempted to explore the effect of valsartan on AT1-AA-induced apoptosis in endothelial progenitor cells.

MATERIALS AND METHODS

Endothelial progenitor cells (EPCs) were cultured. The cytotoxicity was determined by MTT assay. EPCs apoptosis was determined by DAPI staining and flow cytometry. Reactive oxygen species, intracellular calcium concentration and calpain activity were measured using Fluostar Omega Spectrofluorimeter. The expression of p-ERK, p-eIF-2a, CHOP, Bcl-2 and caspase-3 were detected by Western blot.

RESULTS

MTT assays showed valsartan significantly inhibited AT1-AA- induced decline of the viability of EPCs. DAPI staining and flow cytometry results indicated valsartan inhibited AT1-AA-induced decline of the viability of EPCs via inhibiting AT1-AA-induced apoptosis. Furthermore, the increasing of reactive oxygen species, intracellular calcium and calpain activity induced by AT1-AA in EPCs were also recovered after pre-treated with valsartan. Meanwhile, the upregulation of p-ERK, p-eIF-2a and CHOP, downregulation of Bcl-2, and activation of Caspase-3 caused by AT1-AA were reversed after pre-incubated with valsartan.

CONCLUSIONS

Valsartan could inhibit AT1-AA-induced apoptosis through inhibiting oxidative stress mediated ER stress in EPCs.

Abstract S3-07: Impact of radiotherapy on complications and patient-reported satisfaction with breast reconstruction: Findings from the prospective multicenter MROC study

Background: Patients considering both post-mastectomy radiation (RT) and reconstruction require robust information regarding the expected outcomes of different combinations of approaches in order to make preference-concordant decisions.

Methods: In a prospective multicenter cohort study (the Mastectomy Reconstruction Outcomes Consortium, MROC, funded by NCI 1RO1CA152192) of women diagnosed with breast cancer at 11 institutions between 2012-15, we compared responses of 553 radiated and 1461 non-radiated pts who received different approaches to reconstruction. The primary dependent variables of interest were development of any breast complications (e.g. hematoma, wound infection) by one year post-reconstruction, along with satisfaction measured with the validated BREAST-Q instrument. Mixed-effects regression models assessed impact of reconstruction type and RT on the outcomes of interest. Covariate adjustment included reconstruction timing, age, extent of disease, bilateral vs unilateral treatment, chemotherapy receipt, nodal management, BMI, smoking, diabetes, race, ethnicity, education, employment, income, marital status, and hospital site.

Results: Median age was 49. Bilateral mastectomy was received by 45.6% of radiated and 53.3% of non-radiated pts (p=0.002). Autologous reconstruction was more commonly received by radiated pts (38.3% vs 25.1%, p<0.001). Immediate reconstruction was less common in radiated pts (82.6% vs 95.6%, p<0.001). By one year, at least one complication occurred in 28.8% of radiated pts (30.8% of implant pts and 25.5% of autologous pts) and 22.3% of non-radiated pts (20.4% of implant pts and 28.1% of autologous pts). Among pts with ≥2 years of follow up, a complication had occurred by 2 years in 34.1% of 331 radiated pts vs 22.5% of 946 non-radiated pts. Multivariable analysis showed immediate reconstruction, bilateral treatment, & higher BMI to be predictive of developing a complication by one year. RT effect differed by reconstruction type; RT was associated with 2.1 (95% CI = 1.45, 3.10) times higher odds of complication in implant pts, while showing no difference in autologous pts (OR=1.3, 95% CI = 0.76, 2.09). RT effect on patient outcomes also differed by reconstruction types. In implant pts, adjusted mean BREAST-Q satisfaction with breast scores were significantly lower in radiated pts than in non-radiated pts (51.5 vs. 58.0 at 1 year, p<.001; 48.9 vs. 59.8 at 2 years, p<.001), while satisfaction in autologous pts did not differ by radiation (61.3 in radiated vs. 63.5 in non-radiated at 1 year; 62.8 vs. 65.8 at 2 years). Similarly, in implant pts, satisfaction with outcomes was significantly lower in radiated versus non-radiated pts (66.5 vs. 70.8 at 1 year; p=0.03; 64.4 vs. 70.6 at 2 years, p =0.03), while there were no significant differences in autologous pts (72.7 vs. 75.2 in radiated vs. non-radiated at 1 year; 71.3 and 75.3 at year 2).

Conclusions: In the largest prospective multicenter study of outcomes of breast reconstruction to date, autologous reconstruction appears to yield superior patient-reported outcomes and lower risk of complications than implant-based approaches among patients receiving PMRT.

Citation Format: Jagsi R, Momoh AO, Qi J, Hamill JB, Billig J, Kim HM, Pusic AL, Wilkins EG. Impact of radiotherapy on complications and patient-reported satisfaction with breast reconstruction: Findings from the prospective multicenter MROC study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S3-07.

Analysis of gene expression profiles of non-small cell lung cancer at different stages reveals significantly altered biological functions and candidate genes

We attempt to dissect the pathology of non-small cell lung cancer (NSCLC) patients at different stages and discover the novel candidate genes. Microarray data (GSE21933) were retrieved from the Gene Expression Omnibus database. The differential expression profiles of lung tumor tissues during different stages were analyzed. The significantly altered functions and pathways were assessed and the key nodes in a protein-protein interaction (PPI) network were screened out. Then, the coexpression gene pairs and tumor-related genes were assessed. RT-PCR analysis was performed to validate the candidate gene, natural killer-tumor recognition sequence (NKTR). The number of differentially expressed genes (DEGs) for stage IB, IIB, IIIA and IV tumors were 499, 602, 592 and 457, respectively. Most of the DEGs were NSCLC-related genes identified through literature research. A few genes were commonly downregulated in all the 4 stages of tumors, such as CNTN6 and LBX2. The DEGs in early‑stage tumors were closely related with the negative regulation of signal transduction, the apoptosis pathway and the p53 signaling pathway. DEGs in late-stage tumors were significantly enriched in transcription, response to organic substances and synapse regulation-related biological processes. A total of 16 genes (including NKTR) made up the significant coexpression network. NKTR was a key node in the PPI network and was significantly upregulated in lung cancer cells. The mechanism of NSCLC progression in different tumor stages may be different. NKTR may be the target candidate for NSCLC prevention and treatment.

Misinformation is prevalent in psoriasis-related YouTube videos

Background Psoriasis patients seek information online, but little is known about their interaction with YouTube. We examined the quality of content in psoriasis-related YouTube videos and investigated their interactions with viewers.Methods YouTube was searched using the term "psoriasis." Relevant videos in English were independently categorized by two reviewers as useful, misleading, or patient view (regarding experience with psoriasis). Disagreements were settled by a third reviewer. Videos were rated on a Global Quality Scale (GQS) (1=poor, 5=excellent).Results According to our reviewers, 17% of the 47 videos were useful, 21% were misleading, and 62% represented patient views. Mean GQS scores were 4.2 ± 1.3 for useful videos, 1.7 ± 0.7 for misleading videos, and 2.2 ± 1.1 for patient view videos (p<0.001). Video views per day did not differ among the categories (p=0.65), whereas useful videos had fewest "Likes" (useful: 31 ± 55, 33 misleading: 151 ± 218, patient views: 165 ± 325, p=0.06) and comments (useful: 9.8 ± 18.3, misleading: 64.1 ± 89.7, 124.9 ± 34 199.4, p=0.009).Conclusions Useful videos were highest in quality but had similar viewership as misleading and patient view videos, with lower popularity and  engagement of users compared to other categories. Physicians and psoriasis patients should be aware of this pattern when pproaching YouTube as a resource.

Glucocorticoids impair bone formation of bone marrow stromal stem cells by reciprocally regulating microRNA-34a-5p

The inhibitory effects of glucocorticoids (GCs) on bone marrow stromal stem cell (BMSC) proliferation and osteoblastic differentiation are an important pathway through which GCs decrease bone formation. We found that microRNA-34a-5p was a critical player in dexamethasone (Dex)-inhibited BMSC proliferation and osteogenic differentiation. MicroRNA-34a-5p might be used as a therapeutic target for GC-impaired bone formation.

INTRODUCTION

The inhibitory effects of glucocorticoids (GCs) on bone marrow stromal stem cell (BMSC) proliferation and osteoblastic differentiation are an important pathway through which GCs decrease bone formation. The mechanisms of this process are still not completely understood. Recent studies implicated an important role of microRNAs in GC-mediated responses in various cellular processes, including cell proliferation and differentiation. Therefore, we hypothesized that these regulatory molecules might be implicated in the process of GC-decreased BMSC proliferation and osteoblastic differentiation.

METHODS

Western blot, quantitative real-time PCR, and cell proliferation and osteoblastic differentiation assays were employed to investigate the role of microRNAs in GC-inhibited BMSC proliferation and osteoblastic differentiation.

RESULTS

We found that microRNA-34a-5p was reciprocally regulated by Dex during the process of BMSC proliferation and osteoblastic differentiation. Furthermore, we confirmed that microRNA-34a-5p was a critical player in Dex-inhibited BMSC proliferation and osteogenic differentiation. Mechanistic studies showed that Dex inhibited BMSC proliferation by microRNA-34a-5p targeting cell cycle factors, including CDK4, CDK6, and Cyclin D1. Furthermore, downregulation of microRNA-34a-5p by Dex leads to Notch signaling activation, resulting in inhibition of BMSC osteogenic differentiation.

CONCLUSIONS

These results showed that microRNA-34a-5p, a crucial regulator for BMSC proliferation and osteogenic differentiation, might be used as a therapeutic target for GC-impaired bone formation.

[Changes of macrophages in colitis-associated colonic carcinogenesis]

OBJECTIVE

To investigate the changes of quantity and phenotype of macrophages during the progress of colitis-associated carcinogenesis, and to identify the chemokines mediating macrophage recruitment.

METHODS

Colitis-associated cancer was induced by azoxymethane (AOM) combined with dextran sulfate sodium (DSS) in C57BL/6 mice. The three sequential developmental stages of colitis associated cancer in the mice were named AD1, AD2 and AD3, respectively. Colon tissues were collected and digested into single-cell suspension. The percentage and phenotype of macrophages in the colon tissues were determined by fluorescence activated cell sorter (FACS). Protein array and real-time polymerase chain reaction (PCR) were used to predict potential chemotatic factors of macrophages.

RESULTS

Colitis-associated cancer was effectively induced in C57BL/6 mice using AOM combined with DSS. The percentage of macrophages was gradually elevated in the AD1, AD2 and AD3 groups [(9.93±1.28)%, (15.42±1.15)%, (21.25±0.62)%], respectively, significantly higher than that of the control group [(2.39±0.54)%, P<0.01]. The macrophages infiltrating the colonic mucosa exhibited mainly a pro-inflammatory phenotype as CD206(-)CD86(+) MHCII(-). The positive rates of CD206 in the AD1, AD2 and AD3 groups were (15.03±1.54)%, (8.11±3.70)%, and (9.06±1.16)%, respectively, significantly lower than that of the control group [(19.43±7.31)%, P<0.01]. The positive rates of CD86 in the AD2 and AD3 groups were (46.73±6.58)% and (76.90±14.32)%, respectively, significantly higher than that of the control group [(19.37±9.69)%, P<0.01)]. The positive rates of MHCⅡ in the AD1, AD2 and AD3 groups were (31.10±2.69)%, (33.93±14.08)%, and (29.93±1.41)%, respectively, significantly lower than that of the control group [(50.30±6.58)%, P<0.01]. Protein array analysis and real-time PCR data revealed that G-CSF was the potential chemokine to recruit macrophages in the AOM-DSS mouse model.

CONCLUSION

Macrophages infiltrate increasingly during the carcinogenesis and development of colitis-associated cancer, which mostly express CD206(-)CD86(+) MHCII(-) and might be potentially recruited by G-CSF.

Wnt activation protects against neomycin-induced hair cell damage in the mouse cochlea

Recent studies have reported the role of Wnt/β-catenin signaling in hair cell (HC) development, regeneration, and differentiation in the mouse cochlea; however, the role of Wnt/β-catenin signaling in HC protection remains unknown. In this study, we took advantage of transgenic mice to specifically knockout or overactivate the canonical Wnt signaling mediator β-catenin in HCs, which allowed us to investigate the role of Wnt/β-catenin signaling in protecting HCs against neomycin-induced damage. We first showed that loss of β-catenin in HCs made them more vulnerable to neomycin-induced injury, while constitutive activation of β-catenin in HCs reduced HC loss both in vivo and in vitro. We then showed that loss of β-catenin in HCs increased caspase-mediated apoptosis induced by neomycin injury, while β-catenin overexpression inhibited caspase-mediated apoptosis. Finally, we demonstrated that loss of β-catenin in HCs led to increased expression of forkhead box O3 transcription factor (Foxo3) and Bim along with decreased expression of antioxidant enzymes; thus, there were increased levels of reactive oxygen species (ROS) after neomycin treatment that might be responsible for the increased aminoglycoside sensitivity of HCs. In contrast, β-catenin overexpression reduced Foxo3 and Bim expression and ROS levels, suggesting that β-catenin is protective against neomycin-induced HC loss. Our findings demonstrate that Wnt/β-catenin signaling has an important role in protecting HCs against neomycin-induced HC loss and thus might be a new therapeutic target for the prevention of HC death.

Note: Enhancing the sensitivity of roll-angle measurement with a novel interferometric configuration based on waveplates and folding mirror

A novel method for very high resolution measurement of roll angle on a transparent plate is developed theoretically and tested experimentally. The new optical configuration is based on the interferometric readout of phase shift accumulated on the double passage through half wave plate, together with a careful control of polarization state by means of quarter wave plate, and optimizing the tilt of the folding mirror. Sensitivity to roll angle is greatly enhanced and a gain coefficient exceeding 700 is found theoretically, based on Jones' matrix analysis, with a 6-fold increase respect to previous results. In the experimental setup, at the optimum 36° incidence to retroreflector, we measured a gain coefficient of 340. Correspondingly, with an interferometer phase meter resolving 0.01°, a roll-angle resolution 0.1-arc sec is attained.

Effects of non-surgical factors on digital replantation survival rate: a meta-analysis

This study aimed to evaluate the risk factors affecting survival rate of digital replantation by a meta-analysis. A computer retrieval of MEDLINE, OVID, EMBASE, and CNKI databases was conducted to identify citations for digital replantation with digit or finger or thumb or digital or fingertip and replantation as keywords. RevMan 5.2 software was used to calculate the pooled odds ratios. In total, there were 4678 amputated digits in 2641 patients. Gender and ischemia time had no significant influence on the survival rate of amputation replantation (P > 0.05). Age, injured hand, injury type, zone, and the method of preservation the amputated digit significantly influence the survival rate of digital replantation (P < 0.05). Children, right hand, crush, or avulsion and little finger are the risk factors that adversely affect the outcome.

THE LEVEL OF EVIDENCE

Level 5*.

Unraveling Photoinduced Spin Dynamics in the Topological Insulator Bi(2)Se(3)

We report on a time-resolved ultrafast optical spectroscopy study of the topological insulator Bi_{2}Se_{3}. We unravel that a net spin polarization cannot only be generated using circularly polarized light via interband transitions between topological surface states (SSs), but also via transitions between SSs and bulk states. Our experiment demonstrates that tuning photon energy or temperature can essentially allow for photoexcitation of spin-polarized electrons to unoccupied topological SSs with two distinct spin relaxation times (∼25 and ∼300  fs), depending on the coupling between SSs and bulk states. The intrinsic mechanism leading to such distinctive spin dynamics is the scattering in SSs and bulk states which is dominated by E_{g}^{2} and A_{1g}^{1} phonon modes, respectively. These findings are suggestive of novel ways to manipulate the photoinduced coherent spins in topological insulators.