Identification of a Biallelic Missense Variant in Gasdermin D (c.823G > C, p.Asp275His) in a Patient of Atypical Gorham-Stout Disease in a Consanguineous Family

Gorham-Stout disease (GSD), also called vanishing bone disease, is a rare osteolytic disease, frequently associated with lymphangiomatous tissue proliferation. The causative genetic background has not been noted except for a case with a somatic mutation in KRAS. However, in the present study, we encountered a case of GSD from a consanguineous family member. Whole-exome sequencing (WES) analysis focusing on rare recessive variants with zero homozygotes in population databases identified a homozygous missense variant (c.823G > C, p.Asp275His) in gasdermin D (GSDMD) in the patient and heterozygous in his unaffected brother. Because this variant affects the Asp275 residue that is involved in proteolytic cleavage by caspase-11 (as well as -4 and -5) to generate an activating p30 fragment required for pyroptotic cell death and proinflammation, we confirmed the absence of this cleavage product in peripheral monocytic fractions from the patient. A recent study indicated that a shorter p20 fragment, generated by further cleavage at Asp88, has a cell-autonomous function to suppress the maturation of osteoclasts to resorb bone matrix. Thus, the present study suggests for the first time the existence of hereditary GSD cases or novel GSD-like diseases caused by GSDMD deficiency. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Impact of perioperative interruption of antithrombotic therapy on thrombotic and bleeding events in non-cardiac surgery

Funding Acknowledgements

Type of funding sources: None.

Introduction

Antithrombotic therapy including antiplatelet agents and anticoagulants are prescribed for secondary prevention in patients with established cardiovascular disease. Although antithrombotic therapy is often interrupted before non-cardiac surgery with or without perioperative bridging anticoagulation, the impact on thrombotic and bleeding events remains uncertain. 

Purpose

The aim of this study was to clarify the impact of perioperative interruption of anticoagulants on thrombotic and bleeding events in patients with established CVD undergoing elective non-cardiac surgery. 

Methods

A total of 330 patients chronically treated with antithrombotic therapy for secondary prevention underwent elective non-cardiac surgery under general anesthesia, with the complete interruption of antithrombotic agents. The study endpoints included all-cause death, thrombotic events, and major bleeding complications after surgical procedures. 

Results

Of 330 patients, 171 (51.8%) and 159 (48.2%) received antiplatelet agents and anticoagulants perioperatively. Atrial fibrillation (31.8%) and coronary artery disease (20.3%) were the major indications for antithrombotic regimens. Antithrombotic therapy was interrupted from 5 [2, 7] days before the surgery to 4 [2, 7] days postoperatively. Perioperative bridging therapy with unfractionated heparin was employed in 99 (30.0%) patients. During the hospitalization, 3 (0.9%) patients died due to non-cardiovascular causes. Thrombotic events and major bleeding occurred in 2 (0.6%) and 9 (2.7%) patients. Bridging therapy with heparin was non-significantly associated with an increased risk of bleeding events (5.1% vs. 1.7%, p = 0.09). In univariable and multivariable analyses, pre-operative hemoglobin level and operative duration were significantly associated with bleeding complications.

Conclusions

In the present study, complete interruption of antithrombotic therapy resulted in a few thrombotic events with a numerically higher rate of bleeding events in patients undergoing elective non-cardiac surgery. Pre-operative hemoglobin level and operative duration were significantly associated with post-operative bleeding complications.

Combined use of baking soda and electric toothbrushing for removal of artificial extrinsic stain on enamel surface: An in vitro study

Background

This study aimed to investigate the combined effect of baking soda and electric toothbrushing on the removal of artificial extrinsic stain in vitro.

Material and Methods

Flat enamel surfaces of 15 bovine incisors were artificially stained with 10% citric acid / 3% ferric chloride solution followed by 1% tannic acid solution. These specimens were randomly divided into three groups (n = 5) – Group S+B: brushing with an electric toothbrush and baking soda, Group S+C: brushing with an electric toothbrush and fluoride dentifrice, Group S: brushing only with an electric toothbrush. Color values (L*, a*, and b*) and surface roughness were measured before and after brushing (after 1, 2, 3, and 5 min). The data were statistically analyzed using two-way analysis of variance and Tukey’s honest significant difference test as a post hoc test (p< 0.05).

Results

The L* value of Group S+B increased over time, and was significantly different between before brushing and at 5 min (p< 0.05). A significant difference in the ΔE* value of Group S+B was found at 5 min (p< 0.05). However, no significant difference was found in the ΔE* values of Group S+C and Group S. No significant differences in Ra were found in any of the groups.

Conclusions

The results of this study suggest that the combined use of baking soda and electric toothbrushing has an excellent stain-removing effect compared with electric toothbrushing with a fluoride dentifrice. Additionally, the changes in surface roughness were similar to the changes caused by the use of general dentifrices.

Key words:Baking soda, dentifrice, extrinsic stain removal, color change, surface roughness.

miR-766-5p targets super-enhancers by downregulating CBP and BRD4

Super-enhancers (SE) are clusters of transcription enhancers that drive gene expression. SEs are typically characterized by high levels of acetylation of histone H3 lysine 27 (H3K27ac), which is catalyzed by the histone lysine acetyltransferase CREB binding protein (CBP). Cancer cells frequently acquire tumor-specific SEs at key oncogenes, such as MYC, which induce several hallmarks of cancer. BRD4 is recruited to SEs and consequently functions as an epigenetic reader to promote transcription of SE-marked genes in cancer cells. miRNAs can be potent candidates for nucleic acid therapeutics for cancer. We previously identified miR-766-5p as a miRNA that downregulated MYC expression and inhibited cancer cell growth in vitro. In this study, we show that miR-766-5p directly targets CBP and BRD4. Concurrent suppression of CBP and BRD4 cooperatively downregulated MYC expression in cancer cells but not in normal cells. Chromatin immunoprecipitation analysis revealed that miR-766-5p reduced levels of H3K27ac at MYC SEs via CBP suppression. Moreover, miR-766-5p suppressed expression of a BRD4-NUT fusion protein that drives NUT midline carcinoma (NMC). In vivo administration of miR-766-5p suppressed tumor growth in two xenograft models. Collectively, these data suggest that targeting SEs using miR-766-5p-based therapeutics may serve as an effective strategy for the treatment of MYC-driven cancers.

Concurrent targeting of MAP3K3 and BRD4 by miR-3140-3p overcomes acquired resistance to BET inhibitors in neuroblastoma cells

Neuroblastoma (NB) harboring MYCN amplification is a refractory disease with a poor prognosis. As BRD4, an epigenetic reader belonging to the bromodomain and extra terminal domain (BET) family, drives transcription of MYCN in NB cells, BET inhibitors (BETis) are considered useful for NB therapy. However, clinical trials of BETis suggested that early acquired resistance to BETis limits their therapeutic benefit. MicroRNAs are small non-coding RNAs that mediate post-transcriptional silencing of target genes. We previously identified miR-3140-3p as a potent candidate for nucleic acid therapeutics for cancer, which directly targets BRD4. We demonstrated that miR-3140-3p suppresses tumor cell growth in MYCN-amplified NB by downregulating MYCN and MYC through BRD4 suppression. We established BETi-acquired resistant NB cells to evaluate the mechanism of resistance to BETi in NB cells. We revealed that activated ERK1/2 stabilizes MYCN protein by preventing ubiquitin-mediated proteolysis via phosphorylation of MYCN at Ser62 in BETi-acquired resistant NB cells, thereby attenuating the effects of BETi in these cells. miR-3140-3p efficiently downregulated MYCN expression by directly targeting the MAP3K3-ERK1/2 pathway in addition to BRD4 suppression, inhibiting tumor cell growth in BETi-acquired resistant NB cells. This study suggests that miR-3140-3p has the potential to overcome resistance to BETi in NB.

Development of multiband optical sensing method for phenotyping of tomatoes in cultivation site

For the development of a smart food chain, it is necessary to produce stable high-quality agricultural products in the agricultural sector which is the starting point of the food system, and it is important to accumulate and analyse the phenotypic information of agricultural products during cultivation. An easy, rapid, non-destructive and quantitative evaluation method of tree vigor is desirable. This study aimed to develop an X-ray fluorescent (XRF) spectroscopy of fresh leaves and infrared (IR) spectroscopy of fruit juice using a portable device. In addition, the relationship between the spectroscopic information and the surface color of agricultural products was studied. The results showed that the changes in leaf element were in balance and organic matters in the fruits due to slight differences in cultivation conditions were grasped as the XRF and IR spectroscopic information. Furthermore, such changes could be reflected as the differences in the surface color information obtained using the digital camera. Therefore, it was experimentally suggested that the multiband optical sensing could be a powerful and important tool for realizing smart food chains and phenomics research starting from agricultural production.

Suppression of MET Signaling Mediated by Pitavastatin and Capmatinib Inhibits Oral and Esophageal Cancer Cell Growth

Despite increasing knowledge on oral and esophageal squamous cell carcinoma (OSCC and ESCC), specific medicines against both have not yet been developed. Here, we aimed to find novel anticancer drugs through functional cell-based screening of an FDA-approved drug library against OSCC and ESCC. Pitavastatin, an HMGCR inhibitor, emerged as an anticancer drug that inhibits tumor growth by downregulating AKT and ERK signals in OSCC and ESCC cells. One of the mechanisms by which pitavastatin inhibits cell growth might be the suppression of MET signaling through immature MET due to dysfunction of the Golgi apparatus. Moreover, the sensitivity of tumor growth to pitavastatin might be correlated with GGPS1 expression levels. In vivo therapeutic models revealed that the combination of pitavastatin with capmatinib, a MET-specific inhibitor, dramatically reduced tumor growth. Our findings suggest that GGPS1 expression could be a biomarker in cancer therapy with pitavastatin, and the combination of pitavastatin with capmatinib might be a promising therapeutic strategy in OSCC and ESCC. IMPLICATIONS: This study provides new insight into the mechanism of pitavastatin as an anticancer drug and suggests that the combination of pitavastatin with capmatinib is a useful therapeutic strategy in OSCC and ESCC.

Neutrophil Elastase Facilitates Tumor Cell Intravasation and Early Metastatic Events

Functional roles of neutrophil elastase (NE) have not been examined in distinct steps of the metastatic cascade. NE, delivered to primary tumors as a purified enzyme or within intact neutrophils or neutrophil granule content, enhanced human tumor cell intravasation and subsequent dissemination via NE-mediated formation of dilated intratumoral vasculature. These effects depended on picomole range of NE activity, sensitive to its natural inhibitor, α1PI. In Elane-negative mice, the lack of NE decreased lung retention of human tumor cells in experimental metastasis. Furthermore, NE was essential for spontaneous metastasis of murine carcinoma cells in a syngeneic orthotopic model of oral cancer. NE also induced tumor cell survival and migration via Src/PI3K-dependent activation of Akt signaling, vital for tumor cell dissemination in vivo. Together, our findings implicate NE, a potent host enzyme specific for first-responding innate immune cells, as directly involved in early metastatic events and a potential target for therapeutic intervention.

•

NE enhances human carcinoma cell intravasation and spontaneous metastasis

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NE mediates formation of dilated intratumoral vasculature supporting cell intravasation

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NE-KO mice exhibit decreased lung retention and spontaneous metastasis of tumor cells

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NE induces tumor cell survival and migration via activation of Src/PI3K/Akt pathway

Prospective validation of 0-hour/1-hour algorithm using high-sensitivity cardiac troponin I in Japanese patients presenting to emergency department

Background

The diagnostic performance of 0-hour/1-hour algorithm using high-sensitivity cardiac troponin I (hsTnI) for non-ST-segment elevation myocardial infarction (NSTEMI) has not been evaluated in an Asian population.

Purpose

We aimed to prospectively validate the 0-hour/1-hour algorithm using hsTnI in a Japanese population.

Method

We enrolled 754 Japanese patients (mean age of 70 years, 395 men) presenting to our emergency department with symptoms suggestive of NSTEMI. The hsTnI concentration was measured using the Siemens ADVIA Centaur hsTnI assay at presentation and after 1 hour. Patients were divided into three groups according to the algorithm: hsTnI below 3 ng/L (only applicable if chest pain onset &gt;3 hours) or below 6 ng/L and delta 1 hour below 3 ng/L were the “rule-out” group; hsTnI at least 120 ng/L or delta 1 hour at least 12 ng/L were in the “rule-in” group; the remaining patients were classified as the “observe” group. Based on the Fourth Universal Definition of Myocardial Infarction, the final diagnosis was adjudicated by 2 independent cardiologists using all available information, including coronary angiography, coronary computed tomography, and follow-up data. Safety of rule-out was quantified by the negative predictive value (NPV) for NSTEMI, accuracy of rule-in by the positive predictive value (PPV), and overall efficacy by the proportion of patients triaged towards rule-out or rule-in within 1 hour.

Results

Prevalence of NSTEMI was 6.5%. The safety of rule-out (NPV 100%), accuracy of rule-in (PPV 26%), and overall efficacy (54%) were shown in Figure.

Conclusion

The 0-hour/1-hour algorithm using hsTnI is very safe and effective in triaging Japanese patients with suspected NSTEMI.

Funding Acknowledgement

Type of funding source: None

Comparison between optical frequency domain imaging and intravascular ultrasound in PCI guidance for Biolimus A9 eluting stent implantation

Background

It has been reported that intravascular ultrasound (IVUS) guided PCI reduced a risk of major adverse cardiac event compared to conventional angiography guided PCI, while comparison between IVUS-guided and optical frequency domain imaging (OFDI)-guided PCI specifically in long-term clinical outcomes (&gt;1 year) has been unexplored.

Purpose

We sought to compare imaging surrogates at 8 months and clinical outcomes beyond 1 year after drug-eluting stent implantation between IVUS and OFDI guidance.

Methods

The MISTIC-1 is a prospective, multi-centre, single-blinded, randomised-controlled, non-inferiority trial comparing OFDI-guided and IVUS-guided PCI using Biolimus A9 eluting Nobori stent. We enrolled patients with stable coronary artery disease who have symptoms or clinically relevant myocardial ischemia. Stent landing zones were selected in the most normal looking sites with largest lumen and without percentage plaque area &gt;50% in IVUS group while without lipidic plaque of &gt;2 quadrants or suggestive thin-cap fibroatheroma in OFDI group. Stent sizing was based on external elastic lamina (EEL) in IVUS group, while by taking 10% or 0.25mm larger than mean lumen diameter at reference sites in OFDI group. Stent optimisation with in-stent minimum lumen area ≥80% of the average lumen area at proximal and distal reference sites was encouraged in both groups. Primary efficacy endpoint is in-segment minimum lumen area (MLA) assessed by OFDI at 8 months. Secondary safety endpoint is a composite of cardiovascular death, target vessel myocardial infarction, or target lesion revascularisation. Based on the assumption that mean in-segment MLA at follow-up was 4.5mm2 with a standard deviation of 2.0mm2 in the control (IVUS) group and a non-inferiority limit of 1.2mm2 for OFDI group, sample size was estimated as 48 cases in each group with 5% type I error and 90% statistical power.

Results

Since June-2014 and August-2016, we prospectively enrolled 109 patients (mean age 70 years, male 78%) with 126 lesions. Baseline patient and lesion characteristics were well balanced and average nominal size and length of stent used did not differ between OFDI-guided and IVUS-guided PCI (3.0 and 19.1mm vs. 3.1 and 19.3mm, respectively). Post-procedural minimum stent area was 6.24mm2 in OFDI group and 6.72mm2 in IVUS group (p=0.20). At 8-month follow-up, in-segment MLA was 4.56mm2 in OFDI group and 4.13mm2 in IVUS group (P for non-inferiority &lt;0.001). During the follow-up (median 4.5 years [1654 days]), incidence rates of major adverse cardiac event were comparable between the two groups (7.4% in OFDI group and 7.3% in IVUS group, hazard ratio 0.96, 95% CI 0.24–3.83, p=0.95). No definite or probable stent thrombosis were documented in both groups.

Conclusion

OFDI-guided PCI demonstrated comparable results in achieving satisfactory imaging surrogates as well as long-term clinical outcomes after newer generation DES implantation as compared to IVUS-guided PCI.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Suzuken Memorial Foundation

Five-year major adverse cardiac and cerebrovascular events of patients with lipid core abutting lumen (LCAL) on integrated-backscatter intravascular ultrasound undergoing PCI with current DES

Background

Percutaneous Coronary Intervention (PCI) using the new generation drug-eluting stent (DES) has been extremely reduced target lesion revascularization (TLR) in recent years. However, a high incidence of non-target lesion-related cardiovascular events in patients undergoing PCI is an important problem to be solved. According to the previous findings, patients with vulnerable plaques particularly have a high recurrence of cardiovascular events. Little studies, however, has been done to examine the relationship between plaque characteristics on intravascular imaging in a target lesion and non-target lesion-related cardiovascular events.

Purpose

The main objective of this study is to investigate the five-year major adverse cardiac and cerebrovascular events (MACCE) of patients with lipid core abutting lumen (LCAL) on integrated backscatter intravascular ultrasound (IB-IVUS) in a target lesion undergoing PCI with current DES.

Methods and results

Between February 2010 and September 2013, in total 780 patients with ischemic heart disease undergoing PCI, 166 target lesions in 166 consecutive patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) and stable angina pectoris (SAP) undergoing IVUS-guided PCI were studied.

Plaque characteristics in all target lesions were analyzed by three-dimensional IB-IVUS system using the mechanical IVUS catheter. Our previous study has found that LCAL which is defined as a lipid pool directly in contact with the lumen visualizes the thin fibrous cap of less than 75μm on optical coherence tomography (OCT). On the basis of this data, LCAL at minimal lumen area (MLA) site was identified.

In total, 39 patients had lesions with LCAL at MLA site (LCAL(+)), and 127 patients had those without LCAL (LCAL(−)).

The primary endpoint was defined as MACCE, including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and non-TLR for the new lesion during a median follow up of five years. The MACCE occurred significantly higher in the LCAL(+) than in the LCAL(−) (38.5% vs. 17.3%; p&lt;0.005). And the Kaplan-Meier estimates have shown that the cumulative incidence of MACCE was significantly higher in the LCAL(+) than in the LCAL(−) (log rank test, p=0.041). Additionally, after adjustment for confounders, gender, prior PCI and LCAL was the independent predictors for the MACCE of patients undergoing PCI with current DES.

Furthermore, after adding LCAL to a baseline model with established factors consisting of age, gender, diabetes mellitus, prior PCI and percentage lipid volume on IB-IVUS, the net reclassification (p&lt;0.002) and integrated discrimination improvement (p&lt;0.004) significantly improved compared to baseline model alone.

Conclusions

In this study, it has become clear that LCAL on IB-IVUS is likely to be a surrogate marker of MACCE in patients undergoing PCI with current DES.

Funding Acknowledgement

Type of funding source: None

Circulating presepsin (soluble CD14 subtype) as a novel marker of mortality in patients treated at medical cardiac intensive care units

Background

Presepsin, a subtype of soluble CD14, is an inflammatory marker, which largely reflects monocyte activation. The association between presepsin levels and mortality in patients treated at medical cardiac intensive care units (CICUs) remains poorly known.

Objective

We aimed to understand the prognostic value of presepsin levels on admission to medical CICUs for mortality.

Methods

We prospectively studied 1636 heterogeneous patients (median age; 71 years) treated at medical (non-surgical) CICUs. Patients with stage 5 chronic kidney disease (estimated glomerular filtration rate [eGFR] &lt;15 mL/min/1.73 m2) were excluded. Acute coronary syndrome was present in 46% of the patients, and acute decompensated heart failure in 36%. Upon admission, baseline plasma presepsin levels were measured. The primary endpoint was all-cause death.

Results

During a mean follow-up period of 44.6 months after admission, there were 323 (19.7%) deaths. Patients who died were older (median: 75 vs. 71 years, P&lt;0.0001); had higher levels of presepsin (194 vs. 110 pg/mL, P&lt;0.0001), B-type natriuretic peptide (BNP: 520 vs. 144 pg/mL, P&lt;0.0001), high-sensitivity C-reactive protein (hsCRP: 4.7 vs. 2.0 mg/L, P&lt;0.0001), and sequential organ failure assessment (SOFA) score (3 vs. 2, P&lt;0.0001); and had lower levels of eGFR (55 vs. 69 mL/min/1.73m2, P&lt;0.0001) and left ventricular ejection fraction (46% vs. 52%, P&lt;0.0001) than those of the survivors. Multivariate Cox regression analyses revealed presepsin levels as independent predictors of all-cause deaths when assessed as either continuous variables (relative risk [RR] 3.33 per 10-fold increment; P&lt;0.0001) or variables categorized according to quartiles (RR quartile 4 vs. 1, 3.60; P&lt;0.0001). Quartiles of presepsin levels were significantly (P&lt;0.0001) associated with increased risk of mortality (Figure). Adding presepsin levels to a baseline model that included established risk factors, BNP, and hsCRP further enhanced reclassification (P=0.009) and discrimination (P=0.0008) beyond that of the baseline model alone.

Conclusions

Circulating concentration of presepsin on admission may be a potent and independent predictor of mortality, and it may improve the risk stratification of patients admitted at medical CICUs.

Presepsin quartiles and mortality

Funding Acknowledgement

Type of funding source: None

miR-1293, a Candidate for miRNA-Based Cancer Therapeutics, Simultaneously Targets BRD4 and the DNA Repair Pathway

BRD4, a member of the bromodomain and extra-terminal domain (BET) protein family, plays a role in the organization of super-enhancers and transcriptional activation of oncogenes in cancer and is recognized as a promising target for cancer therapy. microRNAs (miRNAs), endogenous small noncoding RNAs, cause mRNA degradation or inhibit protein translation of their target genes by binding to complementary sequences. miRNA mimics simultaneously targeting several tumor-promoting genes and BRD4 may be useful as therapeutic agents of tumor-suppressive miRNAs (TS-miRs) for cancer therapy. To investigate TS-miRs for the development of miRNA-based cancer therapeutics, we performed function-based screening in 10 cancer cell lines with a library containing 2,565 human miRNA mimics. Consequently, miR-1293, miR-876-3p, and miR-6571-5p were identified as TS-miRs targeting BRD4 in this screening. Notably, miR-1293 also suppressed DNA repair pathways by directly suppressing the DNA repair genes APEX1 (apurinic-apyrimidinic endonuclease 1), RPA1 (replication protein A1), and POLD4 (DNA polymerase delta 4, accessory subunit). Concurrent suppression of BRD4 and these DNA repair genes synergistically inhibited tumor cell growth in vitro. Furthermore, administration of miR-1293 suppressed in vivo tumor growth in a xenograft mouse model. These results suggest that miR-1293 is a candidate for the development of miRNA-based cancer therapeutics.

DNA methylation of GJA1, BMP2 and BMP4 in a human cementoblast cell line induced by lipopolysaccharide

AIM

To examine DNA methylation of GJA1, BMP2 and BMP4 in human cementoblasts (HCEM) induced by lipopolysaccharide (LPS).

METHODOLOGY

HCEM were cultured in osteoinduction medium. After 24 h, Escherichia coli LPS (1 μg/mL) was added to the medium, which was changed every 2-3 days. Untreated samples were used as controls. Messenger RNA was extracted after 4 weeks, and quantitative real-time polymerase chain reaction (qRT-PCR) for GJA1, BMP2, BMP4 and DNMT1 was performed. Genomic DNA was extracted after 4 weeks, and quantitative methylation-specific polymerase chain reaction was carried out for GJA1, BMP2 and BMP4. To detect mineralization, alizarin red and alkaline phosphatase staining were performed. The cells were also treated with the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5Aza) and examined. The significance of differences amongst groups was assessed using a two-way analysis of variance (ANOVA) followed by Bonferroni's multiple comparison test with P < 0.05 being significant.

RESULTS

Decreased expression of mRNA was seen in GJA1, BMP2 and BMP4 after 4 weeks (P < 0.05). DNA hypermethylation was detected in GJA1, BMP2 and BMP4 (P < 0.05). Alizarin red staining and alkaline phosphatase staining revealed decreased mineralization levels in HCEM stimulated with LPS. 5Aza abolished the effects of DNA methylation in HCEM stimulated with LPS.

CONCLUSIONS

These results suggest that long-term LPS stimulation induces DNA methylation of GJA1, BMP2 and BMP4 in HCEM.

Massive computational identification of somatic variants in exonic splicing enhancers using The Cancer Genome Atlas

Owing to the development of next-generation sequencing (NGS) technologies, a large number of somatic variants have been identified in various types of cancer. However, the functional significance of most somatic variants remains unknown. Somatic variants that occur in exonic splicing enhancer (ESE) regions are thought to prevent serine and arginine-rich (SR) proteins from binding to ESE sequence motifs, which leads to exon skipping. We computationally identified somatic variants in ESEs by compiling numerous open-access datasets from The Cancer Genome Atlas (TCGA). Using somatic variants and RNA-seq data from 9635 patients across 32 TCGA projects, we identified 646 ESE-disrupting variants. The false positive rate of our method, estimated using a permutation test, was approximately 1%. Of these ESE-disrupting variants, approximately 71% were located in the binding motifs of four classical SR proteins. ESE-disrupting variants occurred in proportion to the number of somatic variants, but not necessarily in the specific genes associated with the biological processes of cancer. Existing bioinformatics tools could not predict the pathogenicity of ESE-disrupting variants identified in this study, although these variants could cause exon skipping. We demonstrated that ESE-disrupting nonsense variants tended to escape nonsense-mediated decay surveillance. Using integrated analyses of open access data, we could specifically identify ESE-disrupting variants. We have generated a powerful tool, which can handle datasets without normal samples or raw data, and thus contribute to reducing variants of uncertain significance because our statistical approach only uses the exon-junction read counts from the tumor samples.

P6178The optimal point of CT-FFR measurement in comparison with invasive FFR

Background

Currently, invasive fractional flow reserve (FFR), has become a gold standard to select patients requiring revascularization. Coronary computed tomography angiography (CTA) -derived FFR (FFRCT/CT-FFR) can be used for the management of coronary artery disease, which would be a gatekeeper of invasive coronary angiography. In most of the previous report to evaluate the diagnostic performance of FFRCT/CT-FFR, FFRCT/CT-FFR value was measured at the same point as the invasive FFR. Clinically, FFRCT/CT-FFR should be measured without the information of invasive FFR. However, optimal measurement point for CT-FFR has not been established yet.

Purpose

To assess the optimal measurement point of CT-FFR in comparison with invasive FFR as a gold standard.

Methods

CTA images scanned at 70–99% of R-R interval with 320 slice CT were screened. In the de-novo lesions with invasive FFR data were included in this study. Since calcified lesions could affect CT-FFR value, severe calcified lesions on CTA were excluded from the analysis. The CT-FFR analysis was performed by 2 cardiologists blinded to the results of the invasive FFR using a standard desktop computer and dedicated software. CT-FFR values could be provided at any point from ostium of coronary artery to the distal with vessel diameter of 1.8mm. To determine the optimal point for measurement of CT-FFR, CT-FFR values were obtained at 3 points in each coronary artery; 1) at the same point as invasive FFR; 2) lowest CT-FFR at distal point of coronary artery; 3) at 2.0 cm distal to the lesion. The diagnostic performance at each point was compared with invasive FFR.

Results

Fifty vessels of 44 patients (average age 68 years, male were 32) were included. Average Agatston score was 279.4. There was significant correlation between CT-FFR at each point and invasive FFR. CT-FFR at the same point as invasive FFR showed the good correlation with invasive FFR (R=0.641, 95% CI= 0.041–0.127, p<0.0001). Compared to the lowest CT-FFR at distal (R=0.608, 95% CI= 0.069–0.160, p<0.0001), CT-FFR at 2.0 cm distal to the lesion (R=0.604, 95% CI= 0.007–0.061, p<0.0001) revealed better correlation with invasive FFR. Sensitivity, specificity, positive and negative predictive value at each point were 92.8 / 93.3 / 81.8; 75.0 / 57.1 / 94.2; 61.9 / 48.2 / 60.0; and 96.0 / 95.2 / 84.6, respectively. Diagnostic accuracy showed that CT-FFR at 2cm distal to the lesion (0.84) was similar to CT-FFR at the same point as invasive FFR (0.80), and it was better than far distal (0.68) to detect invasive FFR derived ischemia.

Conclusions

CT-FFR was feasible to detect invasive FFR derived ischemia at the same point.

CT-FFR at 2.0 cm distal to the lesion showed higher diagnostic performance compared with CT-FFR measured at the far distal. CT-FFR measurement at 2.0 cm distal to the lesion would be a optimal position clinically.

P6171Role of myocardial mass for identifying FFR-verified ischemia and determining therapeutic strategy

Background

Conventional noninvasive approach using coronary CT angiography (CTA) focusing on only coronary artery lesions remains mismatch in identifying functional ischemia and determining indication for coronary revascularization.

Purpose

We aimed to assess the usefulness of CT-verified myocardial mass for identifying FFR-verified myocardial ischemia and determining the indication of coronary revascularization after FFR examination.

Methods

We examined 244 vessels with intermediate stenoses (50 to 90% stenosis visually on CTA) in 216 patients (mean age 69.2±9.2, 166 men) who underwent both coronary CTA and invasive FFR. In addition to coronary stenosis severity and plaque characteristics on visual, minimal lumen diameter (MLD), minimal lumen area (MLA), plaque volume, the entire myocardial volume of the target vessel (MTV) and that exposed to ischemia (FFR ≤0.80) (myocardial volume of ischemia: MVI) were evaluated. Additionally, therapeutic strategy after FFR was recorded.

Results

Of 244 vessels, myocardial ischemia (FFR ≤0.80) was shown in 99 (40.6%). MTV was larger in the patients with FFR-verified ischemia than those without (53.3±19.2 vs. 41.5±21.6, P<0.001); MLA, plaque burden (PB) and percentage of aggregated plaque volume (%APV) were also associated with ischemia. The area under the curves (AUCs) of MLA, PB, %APV, and MTV were 0.69, 0.67, 0.64, and 0.71, respectively. Addition of MTV to a model with coronary stenosis on visual, MLA, PB, and %APV improved C-index (from 0.72 to 0.79, P<0.01), net reclassification improvement (NRI) (0.71, P<0.01), and integrated discrimination improvement (IDI) (0.10, P<0.01). Of 99 vessels with FFR ≤0.80, MVI was larger in the vessels with early revascularization after FFR than those without (38.8 vs. 29.1, P=0.01).

Conclusions

The measurement of myocardial mass improves the diagnostic performance of coronary CTA for the identification of coronary arteries with FFR-verified ischemia. Furthermore, it is associated with therapeutic strategy for the diseased vessels after FFR examination.

P5750Manipulation strategy for crossing coronary chronic total occlusion: an update from the Japanese CTO-PCI expert registry

Background

The percutaneous coronary intervention (PCI) strategy for chronic total occlusion (CTO) based on the guidewire manipulation time remains infrequent.

Purpose

We aimed to assess CTO-PCI strategy on the basis of guidewire manipulation time.

Methods

A total of 5843 patients undergoing CTO PCI between January 2014 and December 2017 and enrolled in the Japanese CTO-PCI expert registry were assessed. Their CTO-PCI strategies, procedural outcomes, and guidewire manipulation time were analysed.

Results

The primary retrograde approach was performed on 1562 patients (26.7%). The overall guidewire and technical success rates were 92.8% and 90.6%, respectively. Median guidewire manipulation time of guidewire success and failure were 56 (interquatile range [IQR]: 22 to 111) min and 176 (IQR: 130 to 229) min, respectively. The average Japanese CTO score of the primary antegrade approach with the antegrade alone, the primary antegrade approach with the retrograde approach, and the primary retrograde approach were 1.7±1.1, 2.1±1.2, and 2.3±1.1, respectively (p<0.001). Median successful guidewire crossing time of single wiring in the antegrade alone was 23 (IQR: 11 to 44) min, and that of the primary retrograde approach was significantly shorter than that of the primary antegrade approach with the retrograde approach (107 [IQR: 70 to 161] min vs. 126 [IQR: 87 to 174] min; p<0.001). Reattempt, CTO length ≥20 mm, and proximal cap ambiguity were the predictors of guidewire failure in the primary antegrade approach with antegrade alone, but were not those in the primary retrograde approach.

Conclusions

Although successful guidewire crossing time of the primary antegrade approach with the antegrade alone is short, that of the primary retrograde approach can be shorter than that of the primary antegrade approach with the retrograde approach. Choosing an appropriate CTO-PCI strategy leads to shortening of successful guidewire crossing time.

P3388Five year outcomes of patients with lipid rich plaque detected three-dimensional Integrated-Backscatter intravascular ultrasound (IB-IVUS) in target lesion after second generation DES implantation

Background

Elective percutaneous coronary intervention (PCI) using second generation drug-eluting stent (DES) has been dramatically reduced restenosis rate. Recently, it has been reported that plaque characterization in nontarget lesion is associated with cardio-vascular events in ischemic heart disease patients undergoing elective PCI. However, it is unclear whether plaque characterization in target lesion is predictor of MACEs (major adverse cardiac events) after elective PCI.

Purposes

The aim of this study is whether plaque characterization detected integrated-backscatter intravascular ultrasound (IB-IVUS) in the target lesion is associated with MACEs in patients with PCI after second generation DES implantation.

Methods and results

Of 700 patients with ischemic heart disease, 552 patients were excluded for chronic totally occlusion, severe calcification hindering precise intracoronary imaging, tortuous lesions, ostial or left main stem lesions and ST-elevated myocardial infarction patients. Finally, 148 consecutive patients who consented to repeated IB-IVUS prior to undergoing elective PCI were recruited in the study.Plaque characterization in target lesion was identified for three-dimensional IB-IVUS technology using the mechanical IVUS catheter (ViewIT, 40 MHz, 2.5 Fr; Terumo, Tokyo, Japan). The median of percentage lipid volume in all target lesions was 47.6%. Furthermore, lipid rich plaque (LRP) group was defined as the lesions consisting of percentage lipid volume greater than the median. And, non-lipid rich plaque (non-LRP) group was defined as the lesions consisting of percentage lipid volume less than the median. MACEs were defined as cardiovascular death, target vessel myocardial infarction, target lesion revascularization and stent thrombosis. The median of follow up period was 60 months. Of the 148 patients, 106 patients had stable angina pectoris. The remaining 42 patients are acute coronary syndrome (NSTE-ACS). 74 patients were classified LRP groups and 74 patients were non-LRP groups. No significant differences were observed between the two groups with respect to age, sex and coronary risk factors. While plaque and vessel volume were greater in the LRP group (216.9±116.3mm3, p<0.001) than non-LRP group (322.5±144.0mm3, p p<0.001). Remodeling index was greater in LRP group (1.02±0.18) than non-LRP group (0.93±0.18, p<0.003). Although MACEs were no significant differences between the two groups, the number of MACEs tend to be more in patients with LRP group (8.1±27.4%) than small lipid group (2.7±16.3, p<0.147). Especially, cardiac death tend to be more in LRP group (6.7±25.2% than non-LRP group (1.3±11.6, p<0.096).

Conclusions

In conclusion, lipid rich plaque detected by three dimensional IB-IVUS system in target lesion with patients undergoing elective PCI may be associated with clinical outcomes for five years after second generation DES implantation.

Acknowledgement/Funding

None

P2240CTA derived plaque characteristics and cardiac events in deferred lesions by invasive FFR

Background

Fractional flow reserve (FFR) based strategy for coronary artery disease (CAD) is widely accepted. However, cardiac events could occur at deferred lesions after FFR. We previous reported that CT derived high risk plaque (HRP) and residual stenosis were the independent predictors of cardiac events.

Purpose

The purpose of this study was to investigate if plaque characteristics on CTA could predict cardiac events in deferred lesions after FFR.

Methods

We included 211 vessels of 193 patients who were deferred revascularization after CTA and invasive FFR. The presence of HRP and the stenosis grading on CTA were analyzed.

Results

Median follow-up period after CTA was 623 days (IQR 302–945). HRP and obstructive stenosis were detected in 58 (27.5%) and 87 (41.2%) lesions, respectively. Cardiac events were occurred in 10 lesions at 440±167 days in average (range: 150–770 days). Multivaliate cox hazard regression analysis revealed that HRP (HR8.01, p=0.0032) and obstructive stenosis with ≥70% (HR 34.93, p<0.0001) were the independent predictors of cardiac events after adjusted for age, sex, and FFR≤0.8. Of 21 lesions with both HRP and obstructive stenosis, 29% lesions resulted in cardiac events in 2 years.

Conclusions

Even in the deferred lesions by invasive FFR, lesions with HRP and obstructive stenosis showed high rate of cardiac events. These lesions should be treated with intensive medical therapy to prevent cardiac events.

P4620Circulating concentration of presepsin improves early prediction of short-term mortality in patients treated at medical cardiac intensive care units

Background

Presepsin, a subtype of soluble CD14, is an inflammatory marker, which largely reflects monocytic activation. Presepsin appears to be an accurate diagnostic marker of sepsis, but its clinical significance remains unclear in cardiovascular disease.

Purpose

This prospective study aimed to investigate the predictive value of plasma presepsin levels on admission to medical (non-surgical) cardiac intensive care units (MCICUs) for short-term mortality.

Methods

We examined 1560 patients hospitalized in MCICUs and measured the baseline plasma presepsin levels at admission.

Results

Acute coronary syndrome was present in 46% of the patients, and acute decompensated heart failure in 36%. Before MCICUs admission, emergent coronary angiography or percutaneous coronary intervention was performed in 36%, mechanical ventilation was required for respiratory insufficiency in 2.1%, and intraaortic balloon pumps were needed for hemodynamic instability in 8.9%. During 6 months after admission, there were 113 (7.2%) deaths. Patients who died were older (median: 77 vs. 71 years, P<0.0001); had higher levels of presepsin (263 vs. 119 pg/mL, P<0.0001), B-type natriuretic peptide (BNP: 696 vs. 186 pg/mL, P<0.0001), high-sensitivity troponin T (hsTnT: 81 vs. 47 pg/mL, P=0.004), and high-sensitivity C-reactive protein (13.8 vs. 2.2 mg/L, P<0.0001); and had lower levels of estimated glomerular filtration rate (50 vs. 65 mL/min/1.73m2, P<0.0001) and left ventricular ejection fraction (43% vs. 51%, P<0.0001) than those of the survivors. In the multivariate Cox regression analysis, higher levels of presepsin (P=0.0002), BNP (P=0.04), and hsTnT (P=0.009) were all independent predictors of 6-month deaths. Quartiles of presepsin levels were associated with higher mortality rates within 6 months after admission (Table). Adding presepsin levels to a baseline model that included established risk factors, BNP, and hsTnT further enhanced reclassification (P=0.004) and discrimination (P=0.003) beyond that of the baseline model.

Mortality rates according to presepsin Presepsin quartile 1st 2nd 3rd 4th P value ≤80 pg/mL 81–124 pg/mL 125–232 pg/mL >232 pg/mL 1-month mortality 0.8% 2.0% 3.3% 8.0% <0.0001 6-month mortality 0.8% 3.8% 8.2% 16.3% <0.0001

Conclusions

Presepsin levels at admission could improve the prediction of short-term mortality in patients hospitalized at MCICUs.

Abstract 163: Identification and characterization of TGFBI in circulating tumor cell subline from pancreatic cancer cell line

Distant metastasis to liver, lung, brain, or bone occurs via circulating tumor cells (CTCs). We hypothesized that a subset of CTCs had more malignant features than tumor cells at the primary site. We established a highly malignant cell line, Panc-1-CTC, derived from the human pancreatic cancer cell line Panc-1 (Panc-1-P) using an in vivo selection method. Panc-1-CTC cells exhibited more profound migratory and invasive abilities than Panc-1-P cells in vitro. In addition, Panc-1-CTC cells had a higher tumor-forming ability than Panc-1-P cells in vivo. To investigate whether a difference in malignant phenotypes exists between Panc-1-P and -CTC cells, we performed comprehensive gene expression array analysis. As a result, Panc-1-CTC significantly expressed transforming growth factor beta-induced (TGFBI), an extracellular matrix protein, more abundantly than did Panc-1-P cells. TGFBI is considered to regulate cell adhesion, but its functions remain unclear. In the present study, knockdown of TGFBI reduced cell migration and invasion abilities, whereas overexpression of TGFBI increased both abilities. Moreover, elevated expression of TGFBI was associated with poor prognosis in patients with pancreatic cancer. Taken together, TGFBI might be targeted for cancer therapy and its expression could be a biomarker for the prediction of prognosis in pancreatic cancer.

Citation Format: Tomoki Muramatsu, Taku Sato, Minoru Tanabe, Johji Inazawa. Identification and characterization of TGFBI in circulating tumor cell subline from pancreatic cancer cell line [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 163.

Fibroblast growth factor signals regulate transforming growth factor-β-induced endothelial-to-myofibroblast transition of tumor endothelial cells via Elk1

The tumor microenvironment contains various components, including cancer cells, tumor vessels, and cancer-associated fibroblasts, the latter of which are comprised of tumor-promoting myofibroblasts and tumor-suppressing fibroblasts. Multiple lines of evidence indicate that transforming growth factor-β (TGF-β) induces the formation of myofibroblasts and other types of mesenchymal (non-myofibroblastic) cells from endothelial cells. Recent reports show that fibroblast growth factor 2 (FGF2) modulates TGF-β-induced mesenchymal transition of endothelial cells, but the molecular mechanisms behind the signals that control transcriptional networks during the formation of different groups of fibroblasts remain largely unclear. Here, we studied the roles of FGF2 during the regulation of TGF-β-induced mesenchymal transition of tumor endothelial cells (TECs). We demonstrated that auto/paracrine FGF signals in TECs inhibit TGF-β-induced endothelial-to-myofibroblast transition (End-MyoT), leading to suppressed formation of contractile myofibroblast cells, but on the other hand can also collaborate with TGF-β in promoting the formation of active fibroblastic cells which have migratory and proliferative properties. FGF2 modulated TGF-β-induced formation of myofibroblastic and non-myofibroblastic cells from TECs via transcriptional regulation of various mesenchymal markers and growth factors. Furthermore, we observed that TECs treated with TGF-β were more competent in promoting in vivo tumor growth than TECs treated with TGF-β and FGF2. Mechanistically, we showed that Elk1 mediated FGF2-induced inhibition of End-MyoT via inhibition of TGF-β-induced transcriptional activation of α-smooth muscle actin promoter by myocardin-related transcription factor-A. Our data suggest that TGF-β and FGF2 oppose and cooperate with each other during the formation of myofibroblastic and non-myofibroblastic cells from TECs, which in turn determines the characteristics of mesenchymal cells in the tumor microenvironment.

Alkaline extracellular conditions promote the proliferation and mineralization of a human cementoblast cell line

AIM

To investigate the proliferation and mineralization of a human cementoblast cell line under alkaline conditions.

METHODOLOGY

A human cementoblast cell line was cultured in alkaline media with several pHs (pH 7.6, 8.0 and 8.4) without CO₂ . Cell numbers, phospho-p44/42 expression, alkaline phosphatase (ALP) activity and mineralization were evaluated. The significance of differences between groups was assessed using two-way analysis of variance 15 (ANOVA) followed by Bonferroni's multiple comparison test (α = 0.01).

RESULTS

Cell numbers increased in a time-dependent manner in the high pH medium groups. Western blot analysis revealed the upregulated expression of phospho-p44/42 under alkaline conditions. ALP activity was also increased at pH 8.0 and 8.4. Alizarin red staining revealed increased mineralization in the high pH medium groups. The incorporation of the transient receptor potential ankyrin subfamily member 1 (TRPA1) antagonist HC030031 markedly negated the effect on proliferation and mineralization.

CONCLUSIONS

Extracellular alkaline conditions promoted the proliferation and mineralization of human cementoblasts in vitro via TRPA1.

Identification and characterization of transforming growth factor beta-induced in circulating tumor cell subline from pancreatic cancer cell line

Distant metastasis to liver, lung, brain, or bone occurs by circulating tumor cells (CTC). We hypothesized that a subset of CTC had features that are more malignant than tumor cells at the primary site. We established a highly malignant cell line, Panc-1-CTC, derived from the human pancreatic cancer cell line Panc-1 using an in vivo selection method. Panc-1-CTC cells showed greater migratory and invasive abilities than its parent cell line in vitro. In addition, Panc-1-CTC cells had a higher tumor-forming ability than parent cells in vivo. To examine whether a difference in malignant phenotypes exists between Panc-1-CTC cells and parent cells, we carried out comprehensive gene expression array analysis. As a result, Panc-1-CTC significantly expressed transforming growth factor beta-induced (TGFBI), an extracellular matrix protein, more abundantly than did parent cells. TGFBI is considered to regulate cell adhesion, but its functions remain unclear. In the present study, knockdown of TGFBI reduced cell migration and invasion abilities, whereas overexpression of TGFBI increased both abilities. Moreover, elevated expression of TGFBI was associated with poor prognosis in patients with pancreatic cancer.

Abstract LB-385: miR-3140 suppresses tumor cell growth by targeting BRD4 via its coding sequence and downregulates the BRD4-NUT fusion oncoprotein

Bromodomain Containing 4 (BRD4) mediates transcriptional elongation of the oncogene MYC by binding to acetylated histones. BRD4 has been shown to play a critical role in tumorigenesis in several cancers, and the BRD4-NUT fusion gene is a driver of NUT midline carcinoma (NMC), a rare but highly lethal cancer. microRNAs (miRNAs) are endogenous small non-coding RNAs that suppress target gene expression by binding to complementary mRNA sequences. Here, we show that miR-3140, which was identified as a novel tumor suppressive miRNA by function-based screening of a library containing 1090 miRNA mimics, directly suppressed BRD4 by binding to its coding sequence (CDS). miR-3140 concurrently downregulated BRD3 by bind to its CDS as well as CDK2 and EGFR by binding to their 3' untranslated regions. miR-3140 inhibited tumor cell growth in vitro in various cancer cell lines, including EGFR tyrosine kinase inhibitor-resistant cells. Interestingly, we found that miR-3140 downregulated the BRD4-NUT fusion protein and suppressed in vitro tumor cell growth in a NMC cell line, Ty-82 cells. Furthermore, administration of miR-3140 suppressed in vivo tumor growth in a xenograft mouse model. Our results suggest that miR-3140 is a candidate for the development of miRNA-based cancer therapeutics.

Citation Format: Tomoki Muramatsu, Erina Tonouchi, Yasuyuki Gen, Hidekazu Hiramoto, Kousuke Tanimoto, Jun Inoue, Johji Inazawa. miR-3140 suppresses tumor cell growth by targeting BRD4 via its coding sequence and downregulates the BRD4-NUT fusion oncoprotein [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-385.

Genome-wide screening of DNA methylation associated with lymph node metastasis in esophageal squamous cell carcinoma

Lymph node metastasis (LNM) of esophageal squamous cell carcinoma (ESCC) is well-known to be an early event associated with poor prognosis in patients with ESCC. Recently, tumor-specific aberrant DNA methylation of CpG islands around the promoter regions of tumor-related genes has been investigated as a possible biomarker for use in early diagnosis and prediction of prognosis. However, there are few DNA methylation markers able to predict the presence of LNM in ESCC. To identify DNA methylation markers associated with LNM of ESCC, we performed a genome-wide screening of DNA methylation status in a discovery cohort of 67 primary ESCC tissues and their paired normal esophageal tissues using the Illumina Infinium HumanMethylation450 BeadChip. In this screening, we focused on differentially methylated regions (DMRs) that were associated with LNM of ESCC, as prime candidates for DNA methylation markers. We extracted three genes, HOXB2, SLC15A3, and SEPT9, as candidates predicting LNM of ESCC, using pyrosequencing and several statistical analyses in the discovery cohort. We confirmed that HOXB2 and SEPT9 were highly methylated in LNM-positive tumors in 59 ESCC validation samples. These results suggested that HOXB2 and SEPT9 may be useful epigenetic biomarkers for the prediction of the presence of LNM in ESCC.

LTBP3 promotes early metastatic events during cancer cell dissemination

Latent Transforming Growth Factor β (TGFβ) Binding Proteins (LTBPs) are important for the secretion, activation and function of mature TGFβ, especially so in cancer cell physiology. However, specific roles of the LTBPs remain understudied in the context of the primary tumor microenvironment. Herein, we investigated the role of LTBP-3 in the distinct processes involved in cancer metastasis. By using three human tumor cell lines of different tissue origin (epidermoid HEp-3 and prostate PC-3 carcinomas and HT-1080 fibrosarcoma) and several metastasis models conducted in both mammalian and avian settings, we show that LTBP-3 is involved in the early dissemination of primary cancer cells, namely in the intravasation step of the metastatic cascade. Knockdown of LTBP-3 in all tested cell lines led to significant inhibition of tumor cell intravasation, but did not affect primary tumor growth. LTBP-3 was dispensable in the late steps of carcinoma cell metastasis that follow tumor cell intravasation, including vascular arrest, extravasation and tissue colonization. However, LTBP-3 depletion diminished the angiogenesis-inducing potential of HEp-3 cells in vivo, which was restorable by exogenous delivery of LTBP-3 protein. A similar compensatory approach rescued the dampened intravasation of LTBP-3-deficient HEp-3 cells, suggesting that LTBP-3 regulates the induction of the intravasation-supporting angiogenic vasculature within developing primary tumors. Using our recently developed microtumor model, we confirmed that LTBP-3 loss resulted in the development of intratumoral vessels with an abnormal microarchitecture incompatible with efficient intravasation of HEp-3 carcinoma cells. Collectively, these findings demonstrate that LTBP-3 represents a novel oncotarget that has distinctive functions in the regulation of angiogenesis-dependent tumor cell intravasation, a critical process during early cancer dissemination. Our experimental data are also consistent with the survival prognostic value of LTBP3 expression in early stage head and neck squamous cell carcinomas, further indicating a specific role for LTBP-3 in cancer progression towards metastatic disease.

Response of porcine epithelial rests of Malassez to stimulation by interleukin-6

AIM

To investigate the proliferation and migration of epithelial cell rests of Malassez (ERM) after stimulation with IL-6.

METHODOLOGY

Porcine-derived ERM were seeded on Dulbecco's modified Eagle's Medium, and IL-6 (100 pg mL^-1 ) was incorporated into the culture medium. The WST-1 assay was performed to evaluate cell proliferation, and absorption was measured at 450 nm. A wound-healing assay and immunofluorescence assay for integrin α₃ were conducted to investigate migration. The Kruskal-Wallis test and the Mann-Whitney U-test with Bonferroni correction were used to analyse data of WST-1 and wound-healing assays.

RESULTS

Cell proliferation following the stimulation by IL-6 increased over time, with a significant increase being observed at 6 h (P < 0.05), but not in a concentration-dependent manner. Cell proliferation was significantly greater in IL-6-treated ERM than in nontreated ERM (P < 0.05). The results of the wound-healing assay revealed earlier closure in IL-6-treated ERM (P < 0.05). In the immunofluorescence assay, integrin α₃ was detected at the edge of cell processes adjacent to the wound area. A neutralized antibody abrogated the effects of the IL-6 stimulation in cell proliferation and migration.

CONCLUSION

IL-6 promoted the proliferation and migration of porcine ERM in vitro.

Chromothripsis-like chromosomal rearrangements induced by ionizing radiation using proton microbeam irradiation system

Chromothripsis is the massive but highly localized chromosomal rearrangement in response to a one-step catastrophic event, rather than an accumulation of a series of subsequent and random alterations. Chromothripsis occurs commonly in various human cancers and is thought to be associated with increased malignancy and carcinogenesis. However, the causes and consequences of chromothripsis remain unclear. Therefore, to identify the mechanism underlying the generation of chromothripsis, we investigated whether chromothripsis could be artificially induced by ionizing radiation. We first elicited DNA double-strand breaks in an oral squamous cell carcinoma cell line HOC313-P and its highly metastatic subline HOC313-LM, using Single Particle Irradiation system to Cell (SPICE), a focused vertical microbeam system designed to irradiate a spot within the nuclei of adhesive cells, and then established irradiated monoclonal sublines from them, respectively. SNP array analysis detected a number of chromosomal copy number alterations (CNAs) in these sublines, and one HOC313-LM-derived monoclonal subline irradiated with 200 protons by the microbeam displayed multiple CNAs involved locally in chromosome 7. Multi-color FISH showed a complex translocation of chromosome 7 involving chromosomes 11 and 12. Furthermore, whole genome sequencing analysis revealed multiple de novo complex chromosomal rearrangements localized in chromosomes 2, 5, 7, and 20, resembling chromothripsis. These findings suggested that localized ionizing irradiation within the nucleus may induce chromothripsis-like complex chromosomal alterations via local DNA damage in the nucleus.

Distribution of Glycoconjugates in the Kidney Studied by Use of Labeled Lectins

Distribution of glycoconjugates in different areas of the rat kidney was studied by light and electron microscopy using six different horseradish peroxidase-labeled lectins. Glomeruli and brush borders of the proximal tubules reacted differently to these lectins, which indicated differences in the carbohydrate compositions of those regions. The ascending limb of Henle's loop (ALH) had strong binding sites for peanut agglutinin (PNA) and soybean agglutinin (SBA). Dolichos biflorus agglutinin (DBA) did not stain the cells of ALH but did stain those of distal convoluted tubules (DCT). DBA is a good marker for distinguishing ALH from DCT. DBA, PNA, and SBA were also good markers of the collecting duct. Ricinus communis agglutinin (RCA-1) and wheat germ agglutinin (WGA) diffusely stained the various components of different parts of the kidney.

Abstract 1992: Exploring target genes of eukaryotic initiation factor 5A in cancer using RNA sequence analysis

Protein synthesis has a key role of maintaining cellular homeostasis such as growth and metabolism. However, dysregulation of translational process is a frequent feature of cancer and contributes to cancer progression. Since oncogenes and tumor suppressor genes are regulated by the translation machinery, therapeutic drugs which target the translation machinery have the possibility for overcoming cancer. We then focused on the hypusine cascade which is related to translational process. In our previous study, we showed that overexpression of the deoxyhypusine synthase (DHPS), an enzyme contained in the hypusine cascade, promoted cancer progression such as migration and invasion ability through RhoA signaling pathway. A DHPS inhibitor, GC7, showed significant decrease in the tumor formation in vivo. In particular, eukaryoutec initiation factor 5A (eIF5A) which is activated by hypusination has important roles of the translational regulation such as initiation and elongation of protein synthesis and nucleocytoplasmic transport of mRNA. We tried to identify the target genes of eIF5A by combining RNA-ChIP method with RNA sequencing analysis. As a result, candidate genes which bound to eIF5A were extracted by bioinformatics analysis, and redundant binding motifs for eIF5A in mRNAs emerged. These findings and future analyses would reveal the regulation of translational machinery by eIF5A which could be an important target for cancer therapy.

Citation Format: Tomoki Muramatsu, Kousuke Tanimoto, Johji Inazawa. Exploring target genes of eukaryotic initiation factor 5A in cancer using RNA sequence analysis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1992.

Significant impact of miRNA-target gene networks on genetics of human complex traits

The impact of microRNA (miRNA) on the genetics of human complex traits, especially in the context of miRNA-target gene networks, has not been fully assessed. Here, we developed a novel analytical method, MIGWAS, to comprehensively evaluate enrichment of genome-wide association study (GWAS) signals in miRNA–target gene networks. We applied the method to the GWAS results of the 18 human complex traits from >1.75 million subjects, and identified significant enrichment in rheumatoid arthritis (RA), kidney function, and adult height (P < 0.05/18 = 0.0028, most significant enrichment in RA with P = 1.7 × 10⁻⁴). Interestingly, these results were consistent with current literature-based knowledge of the traits on miRNA obtained through the NCBI PubMed database search (adjusted P = 0.024). Our method provided a list of miRNA and target gene pairs with excess genetic association signals, part of which included drug target genes. We identified a miRNA (miR-4728-5p) that downregulates PADI2, a novel RA risk gene considered as a promising therapeutic target (rs761426, adjusted P = 2.3 × 10⁻⁹). Our study indicated the significant impact of miRNA–target gene networks on the genetics of human complex traits, and provided resources which should contribute to drug discovery and nucleic acid medicine.

miR-544a induces epithelial-mesenchymal transition through the activation of WNT signaling pathway in gastric cancer

The epithelial-mesenchymal transition (EMT) contributes to cancer progression, as well as the development of normal organs, wound healing and organ fibrosis. We established a cell-based reporter system for identifying EMT-inducing microRNAs (miRNAs) with a gastric cancer (GC) cell line, MKN1, transfected with a reporter construct containing a promoter sequence of VIM in the 5' upstream region of the TurboRFP reporter gene. Function-based screening using this reporter system was performed with a 328-miRNA library, and resulted in the identification miR-544a as an EMT-inducing miRNA. Although miR-544a is already known to be involved in the regulation of CDH1, the mechanism by which EMT occurs remains poorly understood. Herein, we demonstrated that overexpression of miR-544a induces VIM, SNAI1 and ZEB1 expression, and reduces CDH1 expression, resulting in an EMT phenotype. In addition, we found that CDH1 and AXIN2, which are related to the degradation and the translocation of β-catenin, are direct targets of miR-544a. Subsequently, the reduction of CDH1 and AXIN2 by miR-544a induced the nuclear import of β-catenin, suggesting that miR-544a may activate the WNT signaling pathway through the stabilization of β-catenin in nucleus. Our findings raise the possibility that inhibition of miR-544a may be a therapeutic target of metastatic GC.

Abstract 2278: The hypusine cascade promotes cancer progression and metastasis through the regulation of RhoA in squamous cell carcinoma

Metastasis is one of the critical factors contributing to poor prognosis in cancer, but the mechanisms are poorly understood. We established a highly metastatic subline (HOC313-LM) derived from an oral squamous cell carcinoma cell line (HOC313) for uncovering the metastatic mechanisms. We identified deoxyhypusine synthase (DHPS) as a metastasis-related gene through the specific amplification at 19p13.2-p13.13 in the HOC313-LM. Overexpression of DHPS promoted cell motility, invasion and metastasis through activation of the RhoA signaling pathway, and increased the tumor formation in vivo. We also demonstrated that eukaryotic translation factor 5A (eIF5A) bound to RhoA mRNA and regulated its translation. Moreover, GC7, a DHPS inhibitor, showed significant decrease in the tumor formation in vivo. In patients with esophageal squamous cell carcinoma (ESCC), overexpression of DHPS in ESCC tumors was significantly associated with worse recurrence-free survival, and correlated with distant metastasis. Our elucidation of these molecular mechanisms within the hypusine cascade suggests opportunities for novel therapeutic targets in SCC.

Citation Format: Tomoki Muramatsu, Ken-ichi Kozaki, Seiya Imoto, Rui Yamaguchi, Hitoshi Tsuda, Tatsuyuki Kawano, Maki Morishita, Satoru Miyano, Johji Inazawa. The hypusine cascade promotes cancer progression and metastasis through the regulation of RhoA in squamous cell carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2278. doi:10.1158/1538-7445.AM2015-2278

Abstract 3869: Exploration of mechanisms for chromothripsis by irradiation

Chromothripsis is the massive but highly localized chromosome rearrangements within a one-step catastrophic event rather than a series of subsequent and random alterations. Chromothripsis occurs commonly in various human cancers and it is thought to be associated with increasing malignancy and oncogenesis. However the causes and consequences of chromothripsis remain unclear. Therefore, to explore mechanisms of chromothripsis, we investigated whether chromothripsis was artificially induced by irradiation. We elicited DNA double-strand breaks in the oral cancer cell line HOC313, or its highly metastatic subline HOC313-LM by The Single Particle Irradiation system to Cell (SPICE), a focused vertical micro-beam system designed to irradiate the nuclei of adhesive cells. We established irradiated monoclonal sublines and analyzed the copy number variations (CNVs) and SNPs using SNP array. Chromosomal alterations, induced by irradiation including CNVs, were detected in some monoclonal sublines. Interestingly SNP array analysis showed that one subline named LM200-#25 had multiple chromosomal alterations which happened locally in chromosome 7. Moreover, we detected several chromosomal alterations such as t(12;7;11) translocation in LM200-#25 subline by Multi-Color FISH analysis. These results suggested that chromothripsis might be induced by irradiation in LM200-#25 subline.

Citation Format: Maki Morishita, Tomoki Muramatsu, Shin Hayashi, Momoki Hirai, Yumiko Suto, Teruaki Konishi, Keiji Moriyama, Johji Inazawa. Exploration of mechanisms for chromothripsis by irradiation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3869. doi:10.1158/1538-7445.AM2015-3869

Actin stabilization induces apoptosis in cultured porcine epithelial cell rests of Malassez

AIM

To test whether actin stabilization by jasplakinolide induces inhibition of cell viability and apoptosis in epithelial cell rests of Malassez (ERM).

METHODOLOGY

ERM derived from porcine were spread in a 96-well dish (5 × 10(4) /well) using Dulbecco's modified Eagle's medium. The actin-specific stabilization reagent, jasplakinolide, was incorporated into the culture medium and incubated for 24 h. To evaluate cell viability, the WST-1 assay was carried out and absorption (450 nm) was measured. To detect apoptotic cells, monoclonal antibody to single-strand DNA (ssDNA) was used and absorption (405 nm) was measured. Actin stabilization and apoptosis induced by jasplakinolide were morphologically investigated by staining with Alexa Fluor 568 phalloidin and observed under a fluorescent microscope. As a negative control, DMSO was used instead of jasplakinolide. Differences between the jasplakinolide-treated group and the control group were analysed statistically using the Student's t-test.

RESULTS

Cell viability decreased in a concentration-dependent manner, and cell viability in the jasplakinolide-treated ERM was lower than that in nontreated ERM (n = 16, P < 0.01). Apoptotic cells in the jasplakinolide-treated ERM were more frequently detected compared to that in nontreated ERM (n = 16, P < 0.01). Morphologically, shrinkage, irregular forms and fragmentation of nuclei suggesting apoptotic bodies were observed in jasplakinolide-treated ERM, whilst actin filaments were extended in non-treated ERM.

CONCLUSION

Actin stabilization by jasplakinolide inhibited cell viability and induced apoptosis in epithelial cell rests of Malassez.

Abstract 4020: Exploring target gene(s) within chromosome 19-amplification detected in a subclone from metastatic tumors in mouse transplantable OSCC

Cancer metastasis is caused by a highly complex molecular and cellular mechanism. Although this mechanism has been gradually revealed, there are few genes found as useful diagnostic markers or molecular targets for clinical application so far. In this study, we attempted to establish highly metastatic cells by in vivo selection for identifying metastasis-related genes with an oral squamous cell carcinoma cell line (HOC313-parent). As a result, we established a highly metastatic subline (HOC313-LM) derived from a metastatic site of axillary lymph node. To explore metastasis-related genes and signaling pathways, we performed integrative omics including several genomic and epigenomic approaches combined with systems biology. Since the amplification of chromosome 19 was identified in HOC313-LM by array CGH, we focused on this amplicon containing 44 genes. Among them, one gene, which was essential for the posttranslational modification, was associated with tumor formation and metastasis in vivo via the Rho signaling pathway. Indeed, activation of the Rho signaling pathway emerged in HOC313-LM by our systems biology approach using the gene expression data sets. In addition, the expression pattern of this gene correlated with poor disease-free survival and distant metastasis in patients with esophageal squamous cell carcinoma. Then, we performed therapeutic experiments using a known inhibitor of this gene, and found that tumor growth was inhibited by this compound. Taken together, our findings suggested that this gene might serve as a novel molecular target for anti-cancer therapy.

Citation Format: Tomoki Muramatsu, Ken-ichi Kozaki, Seiya Imoto, Rui Yamaguchi, Hitoshi Tsuda, Tatsuyuki Kawano, Satoru Miyano, Johji Inazawa. Exploring target gene(s) within chromosome 19-amplification detected in a subclone from metastatic tumors in mouse transplantable OSCC. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4020. doi:10.1158/1538-7445.AM2014-4020