Kaposi's sarcoma-associated herpesvirus latency-associated nuclear antigen dysregulates expression of MCL-1 by targeting FBW7.

Primary effusion lymphoma (PEL) is an aggressive B cell lymphoma that is etiologically linked to Kaposi's sarcoma-associated herpesvirus (KSHV). Despite standard multi-chemotherapy treatment, PEL continues to cause high mortality. Thus, new strategies to control PEL are needed urgently. Here, we show that a phosphodegron motif within the KSHV protein, latency-associated nuclear antigen (LANA), specifically interacts with E3 ubiquitin ligase FBW7, thereby competitively inhibiting the binding of the anti-apoptotic protein MCL-1 to FBW7. Consequently, LANA-FBW7 interaction enhances the stability of MCL-1 by preventing its proteasome-mediated degradation, which inhibits caspase-3-mediated apoptosis in PEL cells. Importantly, MCL-1 inhibitors markedly suppress colony formation on soft agar and tumor growth of KSHV+PEL/BCBL-1 in a xenograft mouse model. These results strongly support the conclusion that high levels of MCL-1 expression enable the oncogenesis of PEL cells and thus, MCL-1 could be a potential drug target for KSHV-associated PEL. This work also unravels a mechanism by which an oncogenic virus perturbs a key component of the ubiquitination pathway to induce tumorigenesis.

A strategy to prevent atherosclerosis via TNF receptor regulation.

Atherosclerosis is a chronic inflammatory disease of the arterial wall. It has been known that development of atherosclerosis is closely related to activation of tumor necrosis factor α (TNF-α). The objective of this study was to elucidate the effects of TNF-α blockade with brusatol on endothelial activation under pro-atherosclerotic conditions. To this end, we examined the effects of brusatol on TNF-α-induced intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression in human aortic endothelial cells (HAECs) using western blot and THP-1 adhesion assays. Brusatol induced a decrease in TNF-α-induced ICAM-1 and VCAM-1 expression through inhibiting TNFR1 expression, leading to suppression of endothelial inflammation independently of the NRF2 (nuclear factor erythroid 2-related factor 2) pathway. The mechanism underlying brusatol-induced TNF receptor 1 (TNFR1) inhibition was investigated with the aid of protein synthesis, co-immunoprecipitation, and cytokine arrays. Notably, brusatol inhibited TNFR1 protein synthesis and suppressed both the canonical nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) signaling pathway and TNF-α-induced cytokine secretion. We further tested the functional effect of brusatol on atherosclerosis development in vivo using two different atherosclerosis mouse models, specifically, acute partial carotid ligation and conventional chronic high-fat diet-fed mouse models. Administration of brusatol led to significant suppression of atherosclerosis development in both mouse models. Our finding that brusatol prevents atherosclerosis via inhibition of TNFR1 protein synthesis supports the potential of downregulation of cell surface TNFR1 as an effective therapeutic approach to inhibit development of atherosclerosis.

Healing Predictors of Conservative Treatment for Juvenile Osteochondritis Dissecans of the Talus.

OBJECTIVE: To investigate the healing response of juvenile osteochondritis dissecans (JOCD) of the talus after conservative treatment, identify healing predictors, and develop a predictive model for healing. DESIGN: Retrospective study. SETTING: Clinics at a tertiary-level pediatric medical center. PATIENTS: Fifty-five patients (55 ankles) who presented with JOCD. INTERVENTIONS: Patients were managed with cast immobilization followed by activity restriction. MAIN OUTCOME MEASURES: The primary outcome measure of progressive lesion reossification was determined from the latest radiograph, after at least 6 months of nonoperative treatment. Final clinical evaluation was performed by a questionnaire and complementary telephone interview. Multivariate logistic regression was used to determine the influence of age, sex, lesion size, classification, location, duration of symptoms, containment lesion, and the occurrence of cyst-like lesions on healing potential. RESULTS: After nonoperative treatment, 18 (33%) of 55 lesions had failed to progress toward healing. An older age (P = 0.034) and a completely detached but undisplaced (grade III) lesion (P < 0.001) at the time of diagnosis were predictive for the failure of conservative treatment. A multivariate logistic regression best predictor model that included age and grade resulted in the best predicted healing and yielded an area under the curve of 0.920 (P < 0.001). CONCLUSION: In two-thirds of skeletally immature patients, conservative treatment resulted in the progressive healing of JOCD of the talus. For older patients with grade III lesions showing a lower healing probability, surgical treatment should be considered.

New Bone Formation in the Whole Decellularized Cortical Bone Scaffold Using the Model of Revitalizing a Haversian System.

ABSTRACT: Decellularized allogeneic bone chips act as scaffolds for bone tissue regeneration. Owing to their lack of osteogenic potentials compared to autologous bone graft, decellularized bone scaffolds (DBSs) have applied only to small partial bone defects in clinical settings. Furthermore, only decellularized cancellous bone chips have been limitedly used for the purpose of bone regeneration. The cortical bone has less porosity and less osteogenic materials such as bone morphogenetic proteins in comparison with cancellous bone. In this study, we tried to accelerate new bone formation within the decellularized cortical bone scaffold using a vascular pedicle as an in vivo bioreactor.Forty DBSs were divided into 4 groups with different conditionings (DBS+ demineralized bone matrix [DBM], DBS+DBM+me+mesenchymal stem cells, DBS+DBM+vascular pedicle, and DBS+DBM+vascular pedicle+mesenchymal stem cells) and implanted into the back of 5 rabbits. Half of the DBSs were examined at 8 weeks and the other half at 16 weeks to determine vascularization level and osteogenesis within each group. New bone formation and bone-forming cells related to osteogenesis were observed via histological staining. Inclusion of the vascular pedicle resulted in larger areas of bone regeneration. With time, osteon structures became more prominent in groups containing the vascular pedicle.In summary, vascularized DBSs combined with a vascular pedicle have shown promising results for bone regeneration, thereby representing potential therapeutic alternatives for autologous bone grafts or bone tissue free transfer in large or segmental bone defects. In addition, demineralized whole cortical bone matrix along with vascular pedicle and various bone inductive materials, such as DBM and recombinant human bone morphogenetic protein-2, may be an additional new option of an ideal osteoinductive system.

Prevention of Breast Implant Displacement Using the Acellular Dermal Matrix Garter Belt.

BACKGROUND: Since the issue of breast implant-associated anaplastic large cell lymphoma, smooth breast implants tend to be the more preferred option in implant-based breast reconstructions, compared to its use previously. The most unfavorable aspect of smooth implants is lateral and inferior displacements, which are more common in patients who undergo breast reconstruction compared to augmentation mammoplasty. Hence, we introduce a prevention method for implant displacement using an acellular dermal matrix garter belt. METHODS: This study is a retrospective review of patients who had undergone implant-based breast reconstruction between April 2019 and December 2020. Some patients who have highly possibility of implant displacement, had undergone the application of an ADM garter belt to prevent lateral or superior displacement. Implant displacement was assessed before and at least 6 months postoperatively. RESULTS: A total of 155 IBR cases were recorded. ADM garter belts were applied in 27 patients (17.4%) who had a high tendency of implant displacement for several reasons, which could be classified into two categories: wide breast pocket (56%) and tight inferomedial breast pocket (44%). The intraoperative average distance of lateral slipping on patients' reconstructed breasts from the chest wall midline in supine position was 3.02 ± 0.81 cm and corrected to1.54 ± 0.69 cm at least 6 months postoperative follow-up. CONCLUSIONS: We utilized an ADM strap as an internalized garter belt to minimize implant displacement. This ADM garter belt combined with capsuloplasty might be an effective way to prevent the displacement of smooth implants in the patients with a greater risk of implant displacement. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266.

Nipple Reconstruction Using the Semilunar Flap and Omega-shaped Acellular Dermal Matrix Strut.

BACKGROUND: Various operative methods exist for nipple reconstruction. Selection of an appropriate skin flap and core strut material is imperative in achieving a satisfactory outcome in nipple reconstruction. Long-term maintenance of nipple projection requires further investigation by surgeons. We propose a new technique that uses a semilunar flap and omega-shaped acellular dermal matrix (ADM). METHODS: Total 53 nipples were reconstructed by this method. An omega-shaped ADM strut was inserted into the barrel made by a semilunar flap. The footplates of omega-shaped ADM struts were spread out under the subcutaneous tissue of the donor site of the semilunar flap to support the dome of the omega strut. RESULTS: The mean maintenance rate of nipple projection was 95.12 ± 6.30% at 3 weeks, 80.60 ± 8.93% at 3 months, and 71.70 ± 8.67% at 6 months postoperatively when compared to the projection observed in the immediate postoperative period. Thirty-five patients (66.0%) showed a maintenance rate over 70% at 6 months post operation, with most patients (94.3%) demonstrating a maintenance rate greater than 60%. CONCLUSIONS: Our study with the omega-shaped ADM strut showed superior maintenance rates of projection when compared to other studies on that used AlloDerm® as a core strut for nipple reconstruction. Omega-shaped struts, when made with cross-linked thick ADM, supported the skin flap quite well. We propose that our method combining the semilunar flap with an omega-shaped ADM may be a good option for nipple reconstruction. LEVEL OF EVIDENCE IV: "This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266 ."

Nanoparticle-Mediated Blocking of Excessive Inflammation for Prevention of Heart Failure Following Myocardial Infarction.

Severe cardiac damage following myocardial infarction (MI) causes excessive inflammation, which sustains tissue damage and often induces adverse cardiac remodeling toward cardiac function impairment and heart failure. Timely resolution of post-MI inflammation may prevent cardiac remodeling and development of heart failure. Cell therapy approaches for MI are time-consuming and costly, and have shown marginal efficacy in clinical trials. Here, nanoparticles targeting the immune system to attenuate excessive inflammation in infarcted myocardium are presented. Liposomal nanoparticles loaded with MI antigens and rapamycin (L-Ag/R) enable effective induction of tolerogenic dendritic cells presenting the antigens and subsequent induction of antigen-specific regulatory T cells (Tregs). Impressively, intradermal injection of L-Ag/R into acute MI mice attenuates inflammation in the myocardium by inducing Tregs and an inflammatory-to-reparative macrophage polarization, inhibits adverse cardiac remodeling, and improves cardiac function. Nanoparticle-mediated blocking of excessive inflammation in infarcted myocardium may be an effective intervention to prevent the development of post-MI heart failure.

Atorvastatin and blood flow regulate expression of distinctive sets of genes in mouse carotid artery endothelium.

Hypercholesterolemia is a well-known pro-atherogenic risk factor and statin is the most effective anti-atherogenic drug that lowers blood cholesterol levels. However, despite systemic hypercholesterolemia, atherosclerosis preferentially occurs in arterial regions exposed to disturbed blood flow (d-flow), while the stable flow (s-flow) regions are spared. Given their predominant effects on endothelial function and atherosclerosis, we tested whether (1) statin and flow regulate the same or independent sets of genes and (2) statin can rescue d-flow-regulated genes in mouse artery endothelial cells in vivo. To test the hypotheses, C57BL/6 J mice (8-week-old male, n=5 per group) were pre-treated with atorvastatin (10mg/kg/day, Orally) or vehicle for 5 days. Thereafter, partial carotid ligation (PCL) surgery to induce d-flow in the left carotid artery (LCA) was performed, and statin or vehicle treatment was continued. The contralateral right carotid artery (RCA) remained exposed to s-flow to be used as the control. Two days or 2 weeks post-PCL surgery, endothelial-enriched RNAs from the LCAs and RCAs were collected and subjected to microarray gene expression analysis. Statin treatment in the s-flow condition (RCA+statin versus RCA+vehicle) altered the expression of 667 genes at 2-day and 187 genes at 2-week timepoint, respectively (P<0.05, fold change (FC)≥±1.5). Interestingly, statin treatment in the d-flow condition (LCA+statin versus LCA+vehicle) affected a limited number of genes: 113 and 75 differentially expressed genes at 2-day and 2-week timepoint, respectively (P<0.05, FC≥±1.5). In contrast, d-flow in the vehicle groups (LCA+vehicle versus RCA+vehicle) differentially regulated 4061 genes at 2-day and 3169 genes at 2-week timepoint, respectively (P<0.05, FC≥±1.5). Moreover, statin treatment did not reduce the number of flow-sensitive genes (LCA+statin versus RCA+statin) compared to the vehicle groups: 1825 genes at 2-day and 3788 genes at 2-week, respectively, were differentially regulated (P<0.05, FC≥±1.5). These results revealed that both statin and d-flow regulate expression of hundreds or thousands of arterial endothelial genes, respectively, in vivo. Further, statin and d-flow regulate independent sets of endothelial genes. Importantly, statin treatment did not reverse d-flow-regulated genes except for a small number of genes. These results suggest that both statin and flow play important independent roles in atherosclerosis development and highlight the need to consider their therapeutic implications for both.

The Effect of Hyaluronidase on the Fat Graft.

BACKGROUND: Fat grafting has been widely used for facial rejuvenation and soft tissue reconstruction. However, it is associated with a lower retention rate than expected and complications such as fat necrosis or calcification. Several techniques that may increase the survival rate of fat grafts have been proposed. The techniques that promote the recipient sites vascularity to increase the survival rate of fat grafts include administration of growth factors, platelet- rich plasma, and adipose derived-stem cells or preconditioning of the recipient fat graft site. METHODS: In this study, the authors evaluated the effect of hyaluronidase on autologous fat graft survival by pretreatment with hyaluronidase at the recipient site by using an animal model. In the experimental group, the recipient site of the fat graft was pretreated with hyaluronidase before fat grafting, whereas the control group was pretreated with normal saline. RESULTS: After 8 weeks of fat grafting, the average volume retention was 78.2% in the experimental group and 68.6% in control group. Considerable fibrosis between the fat globules in the control group was confirmed with Masson trichrome staining. CD31 immunofluorescence staining was performed and stained vessels were counted. Counted vessel number was significantly greater in the experimental group than in the control group. CONCLUSIONS: Pretreatment of hyaluronidase on the fat graft recipient site is a good option to enhance the outcome of the fat graft in the clinical setting.

The Modified Keystone Flap for Pressure Ulcers: A Modification of the Keystone Flap With Rotation and Advancement.

INTRODUCTION: The reconstruction of extensive soft tissue defects from pressure ulcers is a great challenge. Resurfacing such defects with like tissues and minimizing morbidities are important. Here we present our surgical experience using a novel modified keystone flap for pressure ulcer patients. METHODS: We retrospectively reviewed the data of 13 consecutive cases reconstructed with the modified keystone flaps between March and December, 2017. The mean dimensions of the reconstructed defect were 7.7 × 6.5 cm, while the mean dimensions of the flap were 12.1 × 8.3 cm. RESULTS: Time efficient reconstructions with the modified keystone flap were performed without any following major complications. Minor wound dehiscence occurred in only one case, which soon healed with conservative management. CONCLUSIONS: Considering its simple design, reliable flap survival, minimal donor-site morbidity, optimal flap thickness, and evenly distributed surgical tension, our novel technique of the modified keystone flap is as an excellent surgical option for the reconstruction of pressure ulcers in the gluteal region.

Distribution of internal thoracic artery perforators: A clincal anatomy study.

There are various modifications of the transverse rectus abdominis musculocutaneous flap and deep inferior epigastric perforator flap to reduce the morbidity of the donor site or to augment the vascularity of the flap. For microanastomosis of multiple pedicles, multiple recipient vessels or an intervening vein graft should be provided. In addition, alternative perforator-based flaps used in breast reconstruction have small caliber pedicles. Therefore, small recipient vessels such as internal thoracic artery perforators are more suitable for appropriate microanastomosis. Therefore, it is important to acquaint the distribution and anatomical characteristics of internal thoracic artery perforators. We researched the perforators running in the intercostal spaces under the pectoralis major muscle to provide an overview of the anatomical distribution and characteristics of the perforators in patients who underwent immediate subpectoral implant-based breast reconstructions. In our study, the major perforators (diameter > 1.5 mm) were easily found 2-7 cm medially between the third and fourth intercostal space and were sparse in the lateral area from the midline of the breast (usually 8-9 cm lateral to the midsternal line) and above the third rib. In each side of the breast, the average number of perforators greater than 1.5 mm was 1.6, and the average number of perforators between 1 mm and 1.5 mm in diameter was 3.2. Our results provide information about perforators in the anterior chest wall related to the breast area. Clin. Anat. 32:471-475, 2019. © 2018 Wiley Periodicals, Inc.

Quinacrine-Mediated Inhibition of Nrf2 Reverses Hypoxia-Induced 5-Fluorouracil Resistance in Colorectal Cancer.

5-Fluorouracil (5-FU) is an important chemotherapeutic agent for the systemic treatment of colorectal cancer (CRC), but its effectiveness against CRC is limited by increased 5-FU resistance caused by the hypoxic tumor microenvironment. The purpose of our study was to assess the feasibility of using quinacrine (QC) to increase the efficacy of 5-FU against CRC cells under hypoxic conditions. QC reversed the resistance to 5-FU induced by hypoxia in CRC cell lines, as determined using ATP-Glo cell viability assays and clonogenic survival assays. Treatment of cells with 5-FU under hypoxic conditions had no effect on the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a regulator of cellular resistance to oxidative stress, whereas treatment with QC alone or in combination with 5-FU reduced Nrf2 expression in all CRC cell lines tested. Overexpression of Nrf2 effectively prevented the increase in the number of DNA double-strand breaks induced by QC alone or in combination with 5-FU. siRNA-mediated c-Jun N-terminal kinase-1 (JNK1) knockdown inhibited the QC-mediated Nrf2 degradation in CRC cells under hypoxic conditions. The treatment of CRC xenografts in mice with the combination of QC and 5-FU was more effective in suppressing tumor growth than QC or 5-FU alone. QC increases the susceptibility of CRC cells to 5-FU under hypoxic conditions by enhancing JNK1-dependent Nrf2 degradation.

Disturbed Flow Promotes Arterial Stiffening Through Thrombospondin-1.

BACKGROUND: Arterial stiffness and wall shear stress are powerful determinants of cardiovascular health, and arterial stiffness is associated with increased cardiovascular mortality. Low and oscillatory wall shear stress, termed disturbed flow (d-flow), promotes atherosclerotic arterial remodeling, but the relationship between d-flow and arterial stiffness is not well understood. The objective of this study was to define the role of d-flow on arterial stiffening and discover the relevant signaling pathways by which d-flow stiffens arteries. METHODS: D-flow was induced in the carotid arteries of young and old mice of both sexes. Arterial stiffness was quantified ex vivo with cylindrical biaxial mechanical testing and in vivo from duplex ultrasound and compared with unmanipulated carotid arteries from 80-week-old mice. Gene expression and pathway analysis was performed on endothelial cell-enriched RNA and validated by immunohistochemistry. In vitro testing of signaling pathways was performed under oscillatory and laminar wall shear stress conditions. Human arteries from regions of d-flow and stable flow were tested ex vivo to validate critical results from the animal model. RESULTS: D-flow induced arterial stiffening through collagen deposition after partial carotid ligation, and the degree of stiffening was similar to that of unmanipulated carotid arteries from 80-week-old mice. Intimal gene pathway analyses identified transforming growth factor-ß pathways as having a prominent role in this stiffened arterial response, but this was attributable to thrombospondin-1 (TSP-1) stimulation of profibrotic genes and not changes to transforming growth factor-ß. In vitro and in vivo testing under d-flow conditions identified a possible role for TSP-1 activation of transforming growth factor-ß in the upregulation of these genes. TSP-1 knockout animals had significantly less arterial stiffening in response to d-flow than wild-type carotid arteries. Human arteries exposed to d-flow had similar increases TSP-1 and collagen gene expression as seen in our model. CONCLUSIONS: TSP-1 has a critical role in shear-mediated arterial stiffening that is mediated in part through TSP-1's activation of the profibrotic signaling pathways of transforming growth factor-ß. Molecular targets in this pathway may lead to novel therapies to limit arterial stiffening and the progression of disease in arteries exposed to d-flow.

Mechanosensitive PPAP2B Regulates Endothelial Responses to Atherorelevant Hemodynamic Forces.

RATIONALE: PhosPhatidic Acid Phosphatase type 2B (PPAP2B), an integral membrane protein known as lipid phosphate phosphatase (LPP3) that inactivates lysophosphatidic acid, was implicated in coronary artery disease (CAD) by genome-wide association studies. However, it is unclear whether genome-wide association studies-identified coronary artery disease genes, including PPAP2B, participate in mechanotransduction mechanisms by which vascular endothelia respond to local atherorelevant hemodynamics that contribute to the regional nature of atherosclerosis. OBJECTIVE: To establish the critical role of PPAP2B in endothelial responses to hemodynamics. METHODS AND RESULTS: Reduced PPAP2B was detected in vivo in mouse and swine aortic arch (AA) endothelia exposed to chronic disturbed flow, and in mouse carotid artery endothelia subjected to surgically induced acute disturbed flow. In humans, PPAP2B was reduced in the downstream part of carotid plaques where low shear stress prevails. In culture, reduced PPAP2B was measured in human aortic endothelial cells under atherosusceptible waveform mimicking flow in human carotid sinus. Flow-sensitive microRNA-92a and transcription factor KLF2 were identified as upstream inhibitor and activator of endothelial PPAP2B, respectively. PPAP2B suppression abrogated atheroprotection of unidirectional flow; inhibition of lysophosphatidic acid receptor 1 restored the flow-dependent, anti-inflammatory phenotype in PPAP2B-deficient cells. PPAP2B inhibition resulted in myosin light-chain phosphorylation and intercellular gaps, which were abolished by lysophosphatidic acid receptor 1/2 inhibition. Expression quantitative trait locus mapping demonstrated PPAP2B coronary artery disease risk allele is not linked to PPAP2B expression in various human tissues but significantly associated with reduced PPAP2B in human aortic endothelial cells. CONCLUSIONS: Atherorelevant flows dynamically modulate endothelial PPAP2B expression through miR-92a and KLF2. Mechanosensitive PPAP2B plays a critical role in promoting anti-inflammatory phenotype and maintaining vascular integrity of endothelial monolayer under atheroprotective flow.

Could -79 °C Spray-Type Cryotherapy Be an Effective Monotherapy for the Treatment of Keloid?

Cryotherapy has been regarded as an effective modality for the treatment of keloids, and the spray-type device is one of the novel cryotherapeutic units. However, the biological mechanisms and therapeutic effects of this technique are incompletely studied. We evaluated the clinical efficacy of our cryotherapy protocol with molecular and pathologic evidence for the treatment of keloids. We evenly split each of ten keloid lesions into a non-treated (C-) and treated (C+) area; the C+ area was subjected to two freeze-thaw cycles of spray-type cryotherapy using -79 °C spray-type CryoPen™. This treatment was repeated after an interval of two weeks. The proliferation and migration abilities of the fibroblasts isolated from the dermis under the cryotherapy-treated or untreated keloid tissues (at least 5 mm deep) were compared and pathologic findings of the full layer were evaluated. Molecular analysis revealed that the number of dermal fibroblasts was significantly higher in C+ group as compared with C- group. The dermal fibroblasts from C+ group showed more than two-fold increase in the migration ability as compared with the fibroblasts from C- group. The expression of matrix metallopeptidase 9 was increased by more than two-fold and a significant increase in transforming growth factor beta 1 expression and Smad2/3 phosphorylation level was observed in C+ group. C+ group showed more extensive lymphoplasmacytic infiltration with thicker fibrosis and occasional "proliferating core collagen" as compared with C- group. Thus, -79 °C spray-type cryotherapy is ineffective as a monotherapy and should be used in combination with intralesional corticosteroids or botulinum toxin A for favourable outcomes in the treatment of thick keloids.

Reversal of efflux of an anticancer drug in human drug-resistant breast cancer cells by inhibition of protein kinase Cα (PKCα) activity.

P-glycoprotein (Pgp) is a 170-kDa transmembrane protein that mediates the efflux of anticancer drugs from cells. Pgp overexpression has a distinct role in cells exhibiting multidrug resistance (MDR). We examined reversal of drug resistance in human MDR breast cancer cells by inhibition of protein kinase Cα (PKCα) activity, which is associated with Pgp-mediated efflux of anticancer drugs. PKCα activity was confirmed by measurement of phosphorylation levels of a PKCα-specific peptide substrate (FKKQGSFAKKK-NH2), showing relatively higher basal activity in drug-resistant MCF-7/ADR cells (84 %) than that in drug-sensitive MCF-7 cells (63 %). PKCα activity was effectively suppressed by the PKC inhibitor, Ro-31-7549, and reversal of intracellular accumulation of doxorubicin was observed by inhibition of PKCα activity in MCF-7/ADR cells compared with their intrinsic drug resistance. Importantly, increased accumulation of doxorubicin could enhance the therapeutic efficacy of doxorubicin in MDR cells significantly. These results suggest a potential for overcoming MDR via inhibition of PKCα activity with conventional anticancer drugs.

Bone Scintigraphy in the Diagnosis of Rheumatoid Arthritis: Is There Additional Value of Bone Scintigraphy with Blood Pool Phase over Conventional Bone Scintigraphy?

We aimed to investigate the value of bone scintigraphy with additional blood pool phase (BSBP), compared with conventional bone scintigraphy (CBS), in the assessment of rheumatoid arthritis (RA). A total of 242 patients (43 males, 199 females; 14-78 years) with arthralgia, and underwent BSBP were retrospectively analyzed. On the first physical examination, active arthritis was found in 128 of the 242 patients. Clinical diagnosis was made by a rheumatologist on the basis of the 1987 American College of Rheumatology (ACR) criteria, which are considered to be the gold standard. The diagnostic performances and prognostic value of BSBP and CBS were analyzed in the total patients with arthralgia and in the patients with arthritis. The sensitivity of BSBP (84.2%, 80/95) were significantly higher than that of CBS (74.8%, 72/95) in the patients with arthralgia (P = 0.039). When BSBP was interpreted with the results of elevated/positive anti-CCP antibody, its accuracy over CBS also became significantly higher (86.0%, 208/242 vs. 83.1%, 201/242 respectively, P = 0.021). The diagnostic odds ratio of BSBP positivity was higher than CBS positivity in the patients with arthralgia (26.0, 12.9-52.4 vs. 21.1, 10.8-41.3) and with arthritis (12.0, 4.9-29.4 vs. 10.0, 4.2-23.4). Both BSBP and CBS appear to provide acceptable accuracy and comparable diagnostic performance for diagnosis of RA. However, in the patients with arthralgia, BSBP was found to be more sensitive than CBS and more accurate when interpreted with the result of anti-CCP antibody. This could help physicians diagnose RA in daily clinical practice.

Disturbed flow induces systemic changes in metabolites in mouse plasma: a metabolomics study using ApoE⁻/⁻ mice with partial carotid ligation.

Disturbed blood flow (d-flow) occurring in branched and curved arteries promotes endothelial dysfunction and atherosclerosis, in part, by altering gene expression and epigenomic profiles in endothelial cells. While a systemic metabolic change is known to play a role in atherosclerosis, it is unclear whether it can be regulated by local d-flow. Here, we tested this hypothesis by carrying out a metabolomics study using blood plasma samples obtained from ApoE(-/-) mice that underwent a partial carotid ligation surgery to induce d-flow. Mice receiving sham ligation were used as a control. To study early metabolic changes, samples collected from 1 wk after partial ligation when endothelial dysfunction occurs, but before atheroma develops, were analyzed by high-resolution mass spectrometry. A metabolome-wide association study showed that 128 metabolites were significantly altered in the ligated mice compared with the sham group. Of these, sphingomyelin (SM; m/z 703.5747), a common mammalian cell membrane sphingolipid, was most significantly increased in the ligated mice. Of the 128 discriminatory metabolites, 18 and 41 were positively and negatively correlated with SM, respectively. The amino acids methionine and phenylalanine were increased by d-flow, while phosphatidylcholine and phosphatidylethanolamine were decreased by d-flow, and these metabolites were correlated with SM. Other significantly affected metabolites included dietary and environmental agents. Pathway analysis showed that the metabolic changes of d-flow impacted broad functional networks. These results suggest that signaling from d-flow occurring in focal regions induces systemic metabolic changes associated with atherosclerosis.

Role of flow-sensitive microRNAs in endothelial dysfunction and atherosclerosis: mechanosensitive athero-miRs.

Atherosclerosis preferentially occurs in arterial regions exposed to disturbed flow, in part, due to alterations in gene expression. MicroRNAs (miRNAs) are small, noncoding genes that post-transcriptionally regulate gene expression by targeting messenger RNA transcripts. Emerging evidence indicates that alteration of flow conditions regulate expression of miRNAs in endothelial cells both in vitro and in vivo. These flow-sensitive miRNAs, known as mechano-miRs, regulate endothelial gene expression and can regulate endothelial dysfunction and atherosclerosis. MiRNAs such as, miR-10a, miR-19a, miR-23b, miR-17-92, miR-21, miR-663, miR-92a, miR-143/145, miR-101, miR-126, miR-712, miR-205, and miR-155, have been identified as mechano-miRs. Many of these miRNAs were initially identified as flow sensitive in vitro and were later found to play a critical role in endothelial function and atherosclerosis in vivo through either gain-of-function or loss-of-function approaches. The key signaling pathways that are targeted by these mechano-miRs include the endothelial cell cycle, inflammation, apoptosis, and nitric oxide signaling. Furthermore, we have recently shown that the miR-712/205 family, which is upregulated by disturbed flow, contributes to endothelial inflammation and vascular hyperpermeability by targeting tissue inhibitor of metalloproteinase-3, which regulates metalloproteinases and a disintegrin and metalloproteinases. The mechano-miRs that are implicated in atherosclerosis are termed as mechanosensitive athero-miRs and are potential therapeutic targets to prevent or treat atherosclerosis. This review summarizes the current knowledge of mechanosensitive athero-miRs and their role in vascular biology and atherosclerosis.

Prevention of abdominal aortic aneurysm by anti-microRNA-712 or anti-microRNA-205 in angiotensin II-infused mice.

OBJECTIVE: Abdominal aortic aneurysm (AAA) is characterized as a progressive dilation and degradation of the aortic wall, associated with activation of matrix metalloproteinases (MMPs) and inflammation. Emerging evidence indicates a role for microRNAs (miRNAs) in AAA pathogenesis, but it is unclear whether abdominal aortic endothelial miRNAs play a role in the disease process. We aimed to identify miRNAs in the abdominal aortic endothelium that play a critical role in AAA development. APPROACH AND RESULTS: The mouse model of AAA induced by angiotensin II infusion was used in this study. Through a miRNA array and validation study, we initially identified the murine-specific miR-712 and subsequently its human/murine homolog miR-205 as angiotensin II-induced miRNAs in the abdominal aortic endothelium in vivo and in vitro. Mechanistically, miR-712 stimulated MMP activity in the aortic wall by directly targeting 2 MMP inhibitors: tissue inhibitor of metalloproteinase 3 (TIMP3) and reversion-inducing cysteine-rich protein with kazal motifs (RECK). Silencing of miR-712 and miR-205 by using anti-miR-712 and anti-miR-205, respectively, significantly decreased the aortic MMP activity and inflammation, preventing AAA development in angiotensin II-infused ApoE(-/-) mice. Further, upregulation of 4 angiotensin II-sensitive miRNAs, miR-205, -21, -133b, and -378, identified in this murine study were confirmed in human AAA samples compared with nondiseased control. CONCLUSIONS: Our results demonstrate that angiotensin II-sensitive miR-712 and its human homolog miR-205 downregulate TIMP3 and RECK, which in turn stimulate aortic MMP activity and inflammation, leading to AAA development. Targeting these miRNAs may be a novel therapeutic strategy to prevent AAA.