Not Only Hypoxia- but Radiation-Induced Epithelial-Mesenchymal Transition Is Modulated by Hypoxia-Inducible Factor 1 in A549 Lung Cancer Cells.

Hypoxia leads to post-treatment metastasis and recurrences of cancer via the epithelial-mesenchymal transition (EMT). Radiotherapy itself may also contribute to the acquisition of EMT phenotypes. Despite extensive studies on the EMT driven by either hypoxia or radiation stimuli, the molecular mechanisms characterizing these EMT events remain unclear. Thus, we aimed to evaluate the differences in the molecular pathways between hypoxia-induced EMT (Hypo-EMT) and radiation-induced EMT (R-EMT). Further, we investigated the therapeutic effects of HIF-1α inhibitor (LW6) on Hypo-EMT and R-EMT cells. A549 cells, lung adenocarcinoma cell line, acquired enhanced wound-healing activity under both hypoxia and irradiation. Localization of E-cadherin was altered from the cell membrane to the cytoplasm in both hypoxia and irradiated conditions. Of note, the expression levels of vimentin, one of the major EMT markers, was enhanced in irradiated cells, while it decreased under hypoxia condition. Importantly, LW6 significantly blocked EMT-related malignant phenotypes in both Hypo-EMT cells and R-EMT cells with concomitant re-location of E-cadherin onto the cell membrane. Moreover, LW6 deflected stress responsive signalling, JNK, activated sustainably under hypoxic condition, and the blockage of JNK impaired EMT phenotypes. Together, this work demonstrated the molecular events underlying Hypo-EMT and R-EMT, and highlighted HIF-1α as a therapeutic target not only in Hypo- EMT, but also in R-EMT.

Functional Regulatory Mechanisms Underlying Bone Marrow Mesenchymal Stem Cell Senescence During Cell Passages.

Mesenchymal stem cell (MSC) transplantation is an effective periodontal regenerative therapy. MSCs are multipotent, have self-renewal ability, and can differentiate into periodontal cells. However, senescence is inevitable for MSCs. In vitro, cell senescence can be induced by long-term culture with/without cell passage. However, the regulatory mechanism of MSC senescence remains unclear. Undifferentiated MSC-specific transcription factors can regulate MSC function. Herein, we identified the regulatory transcription factors involved in MSC senescence and elucidated their mechanisms of action. We cultured human MSCs (hMSCs) with repetitive cell passages to induce cell senescence and evaluated the mRNA and protein expression of cell senescence-related genes. Additionally, we silenced the cell senescence-induced transcription factors, GATA binding protein 6 (GATA6) and SRY-box 11 (SOX11), and investigated senescence-related signaling pathways. With repeated passages, the number of senescent cells increased, while the cell proliferation capacity decreased; GATA6 mRNA expression was upregulated and that of SOX11 was downregulated. Repetitive cell passages decreased Wnt and bone morphogenetic protein (BMP) signaling pathway-related gene expression. Silencing of GATA6 and SOX11 regulated Wnt and BMP signaling pathway-related genes and affected cell senescence-related genes; moreover, SOX11 silencing regulated GATA6 expression. Hence, we identified them as pair of regulatory transcription factors for cell senescence in hMSCs via the Wnt and BMP signaling pathways.

Incidence rate and risk factors for radiographic hip osteoarthritis in Japanese men and women: a 10-year follow-up of the ROAD study.

OBJECTIVE: To investigate the incidence and progression rate of radiographic hip osteoarthritis (OA) and its risk factors in Japanese men and women using a large-scale population of a nationwide cohort study, Research on Osteoarthritis/osteoporosis Against Disability (ROAD). METHODS: From the baseline survey of the ROAD study, 2,975 participants (1,043 men and 1,932 women) aged 23-94 years (mean, 70.2 years) living in urban, mountainous, and coastal communities were followed up with hip radiography at 3, 7, and 10 years (mean follow-up, 7.1 years). Radiographs were scored using the Kellgren/Lawrence (K/L) grading system, and radiographic hip OA was defined as K/L ≥ 2. The incidence and progression rate of hip OA were examined. Acetabular dysplasia was defined as a central-edge angle <20°. Cox's proportional hazard model was used to assess risk factors for incident and progressive radiographic hip OA. RESULTS: The incidence rate of radiographic hip OA was 5.6/1,000 person-years and 8.4/1,000 person-years in men and women, respectively. The progression rate of hip OA was 2.2/1,000 person-years and 6.0/1,000 person-years in men and women, respectively. The significant risk factors for incident hip OA were age, obesity, and acetabular dysplasia at baseline (hazard risk [HR] 1.05, 95% confidence interval [CI] 1.03-1.08; 1.78, 1.10-2.75; 2.06, 1.30-3.17, respectively). The significant risk factors for progressive hip OA were baseline hip pain and acetabular dysplasia (HR 5.68, 95%CI 1.07-22.61; 14.78, 3.66-56.06, respectively). CONCLUSION: Continued longitudinal surveys of the ROAD study will contribute to knowledge about and potential prevention of incident and progressive hip OA.

Simultaneous detection of ABL1 mutation and IKZF1 deletion in Philadelphia chromosome-positive acute lymphoblastic leukemia using a customized target enrichment system panel.

INTRODUCTION: Recent clinical outcomes of pediatric Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) vastly improved owing to tyrosine kinase inhibitor (TKI). However, the genetic status would be different in each case with ABL1 gene mutation or copy number variants (CNVs) such as IKZF1 deletion. In particular, the TKI resistant clone with ABL1 kinase mutation remains problematic. The comprehensive assessment of genetic status including mutation, insertion and deletion (indel) and CNVs is necessary. METHODS: We evaluated a next-generation sequencing (NGS)-based customized HaloPlex target enrichment system panel to simultaneously detect coding mutations, indel and CNVs. We analysed approximately 160 known genes associated with hematological disorders in 5 pediatric Ph+ALL patients. RESULTS: Mono-allelic IKZF1 deletions were found in 4 patients at diagnosis. Furthermore, the mono-allelic deletions were found in exons of RB1, EBF1, PAX5 and ETV6 genes. Bi-allelic deletions were detected in CDKN2A and CDKN2B genes in 1 patient. ABL1 mutation was also detected in 1 patient at relapse. These results were almost comparable with the results of the multiplex ligation-dependent probe amplification (MLPA) method or Sanger sequence. CONCLUSION: Next-generation sequencing-based custom HaloPlex target enrichment system panel allows us to detect the coding mutations, indel, and CNVs in pediatric Ph+ALL simultaneously, and its results seem comparable with those of other methods.

Aberrant expression of microRNAs and the miR-1/MET pathway in canine hepatocellular carcinoma.

Canine hepatocellular carcinoma (HCC) is the most common primary hepatic tumour in dogs. MicroRNA (miRNA) dysregulation has been reported in human HCC and shown to have diagnostic and prognostic value; however, there are no data on miRNA expression in canine HCC. The aim of the present study was to investigate differentially expressed miRNAs in canine HCC. Analysis of miRNA expression in canine HCC tissues and cell lines by quantitative reverse transcription PCR showed that miR-1, miR-122, let-7a, and let-7g were downregulated, whereas miR-10b and miR-21 were upregulated in canine HCC. MET is one of the target genes of miR-1. MET was upregulated in canine HCC at the gene and protein levels, and a significant correlation between the concomitant downregulation of miR-1 and upregulation of MET was observed. Fast/intermediate-proliferating canine HCC cell lines had higher MET gene and protein expression levels than the slow-proliferating cell line. These findings suggest that miRNAs are differentially expressed in canine HCC, and that the miR-1/MET pathway may be associated with canine HCC cell proliferation.

Clinical and functional significance of STEAP4-splice variant in CD14+ monocytes in patients with rheumatoid arthritis.

Tumour necrosis factor alpha (TNF)-α-induced adipose-related protein (TIARP) is a negative regulator of inflammation in arthritis model mice. In humans, six-transmembrane epithelial antigen of prostate 4 (STEAP4) (human counterpart of TIARP) is also expressed in CD14+ monocytes from patients with rheumatoid arthritis (RA). Recently, highly levels of exon 3-spliced variant STEAP4 (v-STEAP4) expression have been observed in porcine lung. The aim of this study is to elucidate the expression and functional role of v-STEAP4, comparing it with that of STEAP4, in the pathogenesis of arthritis. We identified v-STEAP4 in CD14+ cells. The expression of STEAP4 and v-STEAP4 was higher in patients with RA than in healthy participants. We also found that STEAP4 and v-STEAP4 were correlated positively with C-reactive protein and that their expression was decreased after treatment with an interleukin (IL)-6 antagonist in patients with RA. To investigate further the role of STEAP4 and v-STEAP4, we produced STEAP4 and v-STEAP4 over-expressing human monocytic cell lines (THP-1) for functional analysis. In the v-STEAP4 over-expressing cells, the production of IL-6 was suppressed significantly, but TNF-α was increased significantly through lipopolysaccharide (LPS) stimulation. Immunoblot analysis revealed that phosphorylated (p-)nuclear factor kappa B (NF-κB) was increased after LPS stimulation and degradation of nuclear factor kappa B inhibitor alpha (IκBα) was sustained, whereas p-signal transducer and activator of transcription 3 (STAT-3) was decreased with v-STEAP4. We identified specific up-regulation of v-STEAP4 in RA monocytes. V-STEAP4 might play a crucial role in the production of TNF-α and IL-6 through NF-κB and STAT-3 pathways, resulting in the generation of RA.

Clinical results of accelerated hypofractionated radiotherapy for central-type small lung tumours.

PURPOSE: We evaluated the efficacy and toxicity of accelerated hypofractionated radiotherapy (ahypof-rt) for central-type small lung tumours. METHODS: Between November 2006 and January 2015, 40 patients with central-type small lung tumours underwent ahypof-rt delivered using 10 MV X-rays and a coplanar 3-field technique. The number of fractions ranged from 24 to 28, with a fraction size of 2.5-3 Gy. A total dose of 69-75 Gy to the isocentre of the planning target volume was administered to each patient. Cumulative survival and local control rates were calculated using the Kaplan-Meier method. RESULTS: The 27 men and 13 women enrolled in the study had a median age of 79 years (range: 60-87 years). The tumour stage was T1a in 9 patients, T1b in 17 patients, and T2a in 14 patients, with a median size of 26.5 cm (range: 11-49 cm). The median follow-up period was 23 months. A complete response was achieved in 3 patients (7.5%), and a partial response, in 17 patients (42.5%). The overall 2-year and 3-year local control rates were 87.3% and 81.8% respectively; the 2-year and 3-year overall survival rates were 78.9% and 66.7% respectively. Grade 3 pneumonitis occurred in 3 patients; no other severe adverse events (≥grade 3) were observed in any patient. CONCLUSIONS: Accelerated hypofractionated radiotherapy using a fraction size of 2.5-3 Gy was highly safe and can be a more effective treatment option than conventional radiotherapy for patients with central-type small lung tumours.

Radiographic measurements of the hip joint and their associations with hip pain in Japanese men and women: the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study.

OBJECTIVE: To investigate radiographic measurements of the hip joint and their associations with hip pain, and the prevalence of acetabular dysplasia defined by radiographic measurements of the hip joint in Japanese men and women using the large-scale population-based cohort of the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study. METHODS: From the baseline survey of the ROAD study (cross-sectional study), 2963 participants (1040 men, 1923 women; mean age, 70.2 years) were analyzed. All participants underwent radiographic examinations of both hips using an anteroposterior view under weight-bearing. Minimum joint space width (mJSW), central-edge (CE) angle, acetabular depth-to-width ratio (ADR), and acetabular head index (AHI) were measured. Associations between these radiographic measurements and hip pain were assessed by calculating odds ratios (ORs) using multivariable logistic-regression analysis. Acetabular dysplasia was defined as a CE angle <20°. RESULTS: Mean radiographic measurements of the hip joint for men were: mJSW, 3.8 mm; CE angle, 30.6°; ADR, 262.1 per 1000; and AHI, 81.4%. For women, these values were: mJSW, 3.4 mm; CE angle, 29.9°; ADR, 262.7 per 1000; and AHI, 81.2%. Associations were seen between hip pain and each of mJSW, CE angle, ADR, and AHI (OR 4.52, 95% confidence interval 3.45-5.97; 1.14, 1.11-1.18; 1.31, 1.24-1.40; and 1.15, 1.12-1.18, respectively). Acetabular dysplasia showed an overall prevalence of 13.9%, and was significantly more prevalent in women than in men (P = 0.012). CONCLUSION: The present study of radiographic measurements of the hip joint showed that mJSW, CE angle, ADR, and AHI were associated with hip pain.

Outcomes of fulvestrant therapy among japanese women with advanced breast cancer: a retrospective multicenter cohort study (JBCRG-C06; Safari).

PURPOSE: This retrospective study evaluated the effect of clinical background and treatment line on time to treatment failure (TTF) in advanced/metastatic breast cancer (AMBC) patients receiving F500 in Japan (UMIN 000015168). METHODS: Patients who commenced F500 treatment were registered at 16 sites in Japan. Correlations between baseline clinicopathological factors, treatment line, and TTF were investigated by Kaplan-Meier analysis. TTF data were analyzed using univariate analysis and multivariate analysis with a Cox proportional hazards model. RESULTS: Data for 1072 patients were available; 1031 patients (96.2%) were evaluable for efficacy. F500 was administered as first-line treatment in 2.0%, second-line in 22.7%, third-line in 26.7%, and ≥fourth-line in 48.6% patients. Median TTF was 5.4 months. Multivariate analysis found that earlier F500 use (first and second vs. third vs. ≥fourth line; hazard ratio (HR) = 0.80, 95% confidence interval (CI) 0.74-0.86; P < 0.001), longer period from AMBC diagnosis to F500 use (≥3 vs. <3 years; HR 0.60, 95% CI 0.51-0.70; P < 0.001), and no prior palliative chemotherapy administered for unresectable or metastatic breast cancer (no vs. yes; HR 0.69, 95% CI 0.60-0.80; P < 0.001) were associated with significantly longer TTF. Among 691 patients, where information on histologic/nuclear grade was available, a low grade was also associated with a longer TTF, but this finding was not maintained among patients with recurrent breast cancer (N = 558). Among women with recurrent breast cancer, a longer DFI between a patient's initial breast cancer diagnosis and their recurrence was associated with a longer TTF on F500 therapy. CONCLUSIONS: Our study showed that treatment period of F500 was longer when used in earlier-line treatment. For patients on F500, TTF was also longer for patients who had not received prior palliative chemotherapy and for those who had a longer period from their AMBC diagnosis to F500 use.

Angular Momentum of Twisted Radiation from an Electron in Spiral Motion.

We theoretically demonstrate for the first time that a single free electron in circular or spiral motion emits twisted photons carrying well-defined orbital angular momentum along the axis of the electron circulation, in adding to spin angular momentum. We show that, when the electron velocity is relativistic, the radiation field contains harmonic components and the photons of lth harmonic carry lℏ total angular momentum for each. This work indicates that twisted photons are naturally emitted by free electrons and are more ubiquitous in laboratories and in nature than ever thought.

Predictors of the response to treatment in acute lupus hemophagocytic syndrome.

OBJECTIVE: The objective of this paper is to identify predictors for the response to treatment of acute lupus hemophagocytic syndrome (ALHS). METHODS: We reviewed seven cases with ALHS admitted to our hospital and published ALHS cases identified in the 2001-2014 Medline database, and then conducted univariate and multivariate analyses to identify predictors for the response to treatment. RESULTS: Review of our cases showed a significant and negative correlation between serum ferritin and anti-DNA antibody (p = 0.0025). All three patients treated with cyclosporine A (CsA) were considered responders despite high serum ferritin and corticosteroid resistance. We also reviewed 93 patients with ALHS identified in 46 articles. Multiple logistic regression analysis identified C-reactive protein (CRP) (OR 0.83, p = 0.042) and hemoglobin (OR 1.53, p = 0.026) measured at diagnosis of ALHS as significant predictors of the response to corticosteroid monotherapy. Moreover, among 32 patients treated with CsA, serum ferritin was significantly higher in CsA responders (12163 ± 16864 µg/l, n = 22) than in non-responders (3456 ± 6267/µg/l, p = 0.020, n = 10). Leukocyte count was significantly lower in the CsA responders (1940.0 ± 972.3/µl) than in the non-responders (3253 ± 2198/µl, p = 0.034). CONCLUSION: Low CRP and high hemoglobin can predict a positive response to corticosteroid monotherapy while high serum ferritin and low leukocyte count can predict a positive response to CsA in patients with ALHS and therefore, when corticosteroid monotherapy is not effective in such cases, CsA could be the first choice of an additional immunosuppressive agent.

Upregulation of non-ß cell-derived vascular endothelial growth factor A increases small clusters of insulin-producing cells in the pancreas.

Pancreatic ß cell-derived vascular endothelial growth factor A (VEGF-A) contributes to normal ß cell function. We therefore hypothesized that non-ß cell-derived VEGF-A may affect its properties in adult mice.We generated transgenic mice expressing human VEGF-A (hVEGF-A) in a visceral smooth muscle cell (SMC)-dominant manner under the control of the transgelin (Tagln/SM22α) promoter via a tamoxifen-induced Cre/loxP recombination system (SM-CreER(T2)/hVEGF mice).SM-CreER(T2)/hVEGF mice received tamoxifen orally followed by microscopic examination of their pancreas 4 weeks after the hVEGF-A induction. The number of clusters of insulin-producing cells (IPCs) in islets, pancreatic ducts, and individual IPCs were counted.The number of small IPC clusters (100-215 µm(2)) in the pancreas increased significantly in SM-CreER(T2)/hVEGF mice compared with SM-CreER(T2)(Ki) mice (473 out of 1 992 counts vs. 199 out of 976 counts, p<0.05), although total IPC area and the number of pancreatic duct IPCs, in proportion to exocrine area, were similar between the 2 groups. Although most small IPC clusters observed in SM-CreER(T2)/hVEGF mice were not accompanied by α and/or δ cells, some were attached to a single or a few α cells. An STZ-induced diabetic state in SM-CreER(T2)/hVEGF mice was slightly ameliorated, with only one point of significance 12 weeks after STZ administration, compared with SM-CreER(T2)(Ki) mice.Upregulation of non-ß cell-derived VEGF-A may alter the composition of pancreatic IPCs by increasing the number of small IPC clusters. These findings provide new information on the role of non-ß cell-derived VEGF-A to IPC regeneration and insulin production.

Minimal incision transinguinal repair for incarcerated obturator hernia.

BACKGROUND: Patients with incarcerated obturator hernia are usually elderly, frail, and physically inactive women with serious comorbidities. Although a laparotomy is standard surgical intervention for emergency incarcerated or strangulated obturator hernia, it is invasive particularly for these high-risk patients. The aim of this study is to show the feasibility of minimum open inguinal approach to reduce surgical risk for preoperatively diagnosed incarcerated obturator hernia. METHODS: Between April 2008 and July 2012, 3 consecutive incarcerated obturator hernia patients at Kamitsuga General Hospital who were diagnosed preoperatively by computed tomography underwent the following procedure. First a 4 cm inguinal hernia incision and preperitoneal dissection through the opening of the deep inguinal ring are made. The obturator hernia can be easily found 2 cm dorsally from the Cooper's ligament extraperitoneally. A small incision is made at medial sharp edge of the hernia defect. The hernia sac and its content can then be reduced. If the incarcerated bowel is viable, a prosthetic mesh is placed as a patch. If the bowel is necrotic, the damaged bowel loop is withdrawn through the wound and easily reconstructed extra-abdominally. RESULTS: All operations were successfully completed with this procedure. All patients recovered without incident. CONCLUSIONS: Minimal incision transinguinal repair for diagnosed incarcerated obturator hernia is feasible and provides an improved option to more invasive procedures.

Overexpression of Cdk6 and Ccnd1 in chondrocytes inhibited chondrocyte maturation and caused p53-dependent apoptosis without enhancing proliferation.

Cell proliferation and differentiation are closely coupled. However, we previously showed that overexpression of cyclin-dependent kinase (Cdk6) blocks chondrocyte differentiation without affecting cell-cycle progression in vitro. To investigate whether Cdk6 inhibits chondrocyte differentiation in vivo, we generated chondrocyte-specific Cdk6 transgenic mice using Col2a1 promoter. Unexpectedly, differentiation and cell-cycle progression of chondrocytes in the Cdk6 transgenic mice were similar to those in wild-type mice. Then, we generated chondrocyte-specific Ccnd1 transgenic mice and Cdk6/Ccnd1 double transgenic mice to investigate the possibility that Cdk6 inhibits chondrocyte differentiation through E2f activation. Bromodeoxyuridine (BrdU)-positive chondrocytes and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive chondrocytes were increased in number, and chondrocyte maturation was inhibited only in Cdk6/Ccnd1 transgenic mice (K6(H)/D1(H) mice), which showed dwarfism. Retinoblastoma protein (pRb) was highly phosphorylated but p107 was upregulated, and the expression of E2f target genes was dysregulated as shown by upregulation of Cdc6 but downregulation of cyclin E, dihydrofolate reductase (dhfr), Cdc25a and B-Myb in chondrocytes of K6(H)/D1(H) mice. Similarly, overexpression of Cdk6/Ccnd1 in a chondrogenic cell line ATDC5 highly phosphorylated pRb, upregulated p107, induced apoptosis, upregulated Cdc6 and downregulated cyclin E, dhfr and B-Myb and p107 small interfering RNA reversed the expression of downregulated genes. Further, introduction of kinase-negative Cdk6 and cyclin D1 abolished all effects by Cdk6/cyclin D1 in ATDC5 cells, indicating the requirement of the kinase activity on these effects. p53 deletion partially restored the size of the skeleton and almost completely rescued chondrocyte apoptosis, but failed to enhance chondrocyte proliferation in K6(H)/D1(H) mice. These findings indicated that Cdk6/Ccnd1 overexpression inhibited chondrocyte maturation and enhanced G1/S cell-cycle transition by phosphorylating pRb, but the chondrocytes failed to accomplish the cell cycle, and underwent p53-dependent apoptosis probably due to the dysregulation of E2f target genes. Our findings also indicated that p53 deletion in addition to the inactivation of Rb was not sufficient to accelerate chondrocyte proliferation, suggesting the resistance of chondrocytes to sarcomagenesis.

Profiles of vitamin D insufficiency and deficiency in Japanese men and women: association with biological, environmental, and nutritional factors and coexisting disorders: the ROAD study.

UNLABELLED: Assessments of serum 25-hydroxyvitamin D levels in 1,683 Japanese from a population-based cohort revealed prevalences of vitamin D insufficiency and deficiency were 81.3 and 1.2%, respectively. Vitamin D deficiency was significantly associated with female sex, examined month, current smoking, lack of regular walking, higher intact parathyroid hormone (iPTH), and poor daily vitamin D intake. INTRODUCTION: To clarify the characteristics of subjects with vitamin D insufficiency and deficiency among men and women in the general Japanese population. METHODS: We initiated research on osteoarthritis/osteoporosis against disability (ROAD), a large-scale population-based cohort study, in 2005-2007. Blood examination was performed to measure serum 25-hydroxyvitamin D (25D) and iPTH levels and biochemical markers of bone turnover in 1,683 participants (595 men, 1,088 women). Participants completed an interviewer-administered questionnaire, measurements of bone mineral density, and x-ray examination. Vitamin D deficiency and insufficiency were defined by serum 25D levels <10 and ≥10 but <30 ng/mL, respectively. RESULTS: The prevalence of vitamin D insufficiency and deficiency was 81.3 and 1.2%, respectively. Multinominal logistic regression analyses using potentially confounding variables revealed vitamin D insufficiency was significantly associated with age (+1 year, relative risk ratio, 0.98; 95% confidence interval, 0.96-0.99), gender (women vs. men, 2.28; 1.59-3.30), residing areas (coastal area vs. mountainous area, 0.58; 0.41-0.81), examined month (October, November, December vs. January, 0.51; 0.34-0.76), and serum levels of iPTH (+1 pg/mL, 1.02; 1.01-1.03). Vitamin D deficiency was significantly characterised by female sex (20.5; 3.1-136.7), examined month (0.28; 0.09-0.95), current smoking habit (6.39; 1.78-23.0), lack of regular outside walking (3.96; 1.34-11.7), higher iPTH (1.02; 1.01-1.03) and poor daily vitamin D intake (+10 µg/day, 0.48; 0.24-0.93). CONCLUSIONS: A high prevalence of vitamin D insufficiency and a low prevalence of vitamin D deficiency were found in Japanese men and women, and the characteristics of vitamin D status were clarified.

Antimicrobial peptide LL37 promotes vascular endothelial growth factor-A expression in human periodontal ligament cells.

BACKGROUND AND OBJECTIVE: LL37, originally found in the innate immune system, is a robust antimicrobial peptide. LL37 exhibits multiple bio-functions in various cell types, such as migration, cytokine production, apoptosis, and angiogenesis besides its antimicrobial activity Periodontal ligament (PL) cells play a pivotal role in periodontal tissue regeneration. Based on these findings, we hypothesized that LL37 can regulate PL cell function to promote regeneration of periodontal tissue. To prove this hypothesis, we investigated the effect of LL37 on the potent angiogenic inducer vascular endothelial growth factor (VEGF) expression in cultures of human PL (HPL) cells because neovascularization is indispensable for the progress of tissue regeneration. Moreover, we investigated the signaling cascade associated with LL37-induced VEGF expression. MATERIAL AND METHOD: HPL cells were treated with synthesized LL37 in the presence or absence of PD98059, a MEK-ERK inhibitor, or PDTC, an NF-κB inhibitor. VEGF expression levels were assessed by real-time polymerase chain reaction analysis and an enzyme-linked immunoassay. Phosphorylation levels of ERK1/2 or NF-κB p65 were determined by Western blotting. RESULTS: LL37 upregulated VEGF-A expression at the mRNA and protein levels in HPL cells, while VEGF-B mRNA expression was not affected. Both ERK and NF-κB inhibitors clearly abrogated the increase in VEGF-A levels induced by LL37 in HPL cells. Importantly, LL37 increased phosphorylated levels of ERK1/2 and NF-κB p65 in HPL cells. CONCLUSION: LL37 induces VEGF-A production in HPL cells via ERK and NF-κB signaling cascades, which may result in angiogenesis, thereby contributing to periodontal regeneration.

Irsogladine maleate regulates epithelial barrier function in tumor necrosis factor-α-stimulated human gingival epithelial cells.

BACKGROUND AND OBJECTIVE: As epithelial cells function as a mechanical barrier, the permeability of the gingival epithelial cell layer indicates a defensive capability against invasion by periodontal pathogens. We have reported the expression of claudin-1 and E-cadherin, key regulators of permeability, in the gingival junctional epithelium. Irsogladine maleate (IM) is a medication for gastric ulcers and also regulates Aggregatibacter actinomycetemcomitans-stimuated chemokine secretion and E-cadherin expression in gingival epithelium. In this study, we have further investigated the effects of IM on the barrier functions of gingival epithelial cells under inflammatory conditions. MATERIAL AND METHODS: We examined the permeability, and the expression of claudin-1 and E-cadherin, in human gingival epithelial cells (HGECs) stimulated with tumor necrosis factor (TNF)-α, with or without IM. RESULTS: TNF-α increased the permeability of HGECs, and IM abolished the increase. TNF-α reduced the expression of E-cadherin in HGECs, and IM reversed the reduction. In addition, immunofluorescence staining showed that TNF-α disrupted claudin-1 expression in HGECs, and IM reversed this effect. CONCLUSION: The results suggest that IM reverses the TNF-α-induced disruption of the gingival epithelial barrier by regulating E-cadherin and claudin-1.