Elucidation of molecular basis of osteolytic bone lesions in advanced multiple myeloma

Osteolytic bone lesion is a major cause of decreased quality of life and poor prognosis in patients with multiple myeloma (MM), but molecular pathogenesis of the osteolytic process in MM remains elusive. Fms-like tyrosine kinase 3 ligand (FLT3L) was reported to be elevated in bone marrow and blood of patients with advanced MM who often show osteolysis. Here, we investigated a functional link of FLT3L to osteolytic process in MM. We recruited 86, 306 and 52 patients with MM, acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), respectively. FLT3L levels of patients with hematologic malignancies were measured in bone marrow-derived plasma and found to be significantly elevated in MM than in AML or ALL that rarely show osteolysis. FLT3L levels were further elevated in MM patients with bone lesion compared with patients without bone lesion. In vitro cell-based assays showed that the administration of FLT3L to HEK293T, HeLa and U2OS cells led to an increase in the DKK1 transcript level through STAT3 phosphorylation at tyrosine 705. WNT reporter assay showed that FLT3L treatment reduced WNT signaling, and nuclear translocation of β-catenin. These results collectively show that FLT3L-STAT3-DKK1 pathway inhibits WNT signaling-mediated bone formation in MM, which can cause osteolytic bone lesion. Finally, transcriptomic profiles revealed that FLT3L and DKK1 were predominantly elevated in the hyperdiploidy subtype of MM. Taken together, FLT3L can serve as a promising biomarker for predicting osteolytic bone lesion and also a potential therapeutic target to prohibit the progression of osteolytic process in MM with hyperdiploidy.

Lower Plasma Amyloid Beta - 42 Levels Associated With Worse Survival in Patients With Glioma

BACKGROUND/AIM

Glioma is often refractory. The accumulation of amyloid beta (Aβ) in the brain is commonly associated with Alzheimer's disease (AD), but there are studies suggesting that Aβ has tumor suppressor potential. The aim of this study was to identify a novel, non-invasive candidate biomarker for histological prediction and prognostic assessment of glioma.

PATIENTS AND METHODS

Serum was prepared from blood samples collected preoperatively from 48 patients with WHO grade II-IV glioma between October 2004 and December 2017 at a single tertiary institution. The concentration of Aβ42 was measured using the SMCxPRO immunoassay (Merck). The clinical and histological characteristics of the patients, including molecular subtypes, were reviewed.

RESULTS

The mean age of the patients was 52.2±12.5 years. The mean value of serum Aβ42 concentration was 7.6±7.8 pg/ml in the anaplastic astrocytoma (WHO grade III) group and 6.4±6.5 pg/ml in the glioblastoma multiforme (WHO grade IV) group. The Negative epidermal growth factor receptor (EGFR) expression was associated with higher serum Aβ42 levels (p=0.020). Kaplan-Meier analysis demonstrated that patients with high serum Aβ42 (>11.78 pg/ml) had significantly longer progression-free survival (PFS) (p=0.038) and overall survival (OS) (p=0.018).

CONCLUSION

This study investigated serum Aβ42 levels as a potential biomarker for glioma. The results showed that low serum Aβ42 levels were associated with EGFR expression and poor PFS and OS. Overall, these findings suggest a potential role of Aβ42 as a prognostic marker in astrocytomas.

Identification of novel Carnobacterium maltaromaticum strains in bone marrow samples of patients with acute myeloid leukemia using a metagenomic binning approach

The aim of this study aimed to examine the existence of a bacterial metagenome in the bone marrow of patients with acute myeloid leukemia (AML). We re-examined whole-genome sequencing data from the bone marrow samples of seven patients with AML, four of whom were remitted after treatment, for metagenomic analysis. After the removal of human reads, unmapped reads were used to profile the species-level composition. We used the metagenomic binning approach to confirm whether the identified taxon was a complete genome of known or novel strains. We observed a unique and novel microbial signature in which Carnobacterium maltaromaticum was the most abundant species in five patients with AML or remission. The complete genome of C. maltaromaticum "BMAML_KR01," which was observed in all samples, was 100% complete with 8.5% contamination and closely clustered with C. maltaromaticum strains DSM20730 and SF668 based on single nucleotide polymorphism variations. We identified five unique proteins that could contribute to cancer progression and 104 virulent factor proteins in the BMAML_KR01 genome. To our knowledge, this is the first report of a new strain of C. maltaromaticum in patients with AML. The presence of C. maltaromaticum and its new strain in patients indicates an urgent need to validate the existence of this bacterium and evaluate its pathophysiological role.

Enrichment of Activated Fibroblasts as a Potential Biomarker for a Non-Durable Response to Anti-Tumor Necrosis Factor Therapy in Patients with Crohn's Disease

We investigated whether the response to anti-tumor necrosis factor (anti-TNF) treatment varied according to inflammatory tissue characteristics in Crohn's disease (CD). Bulk RNA sequencing (RNA-seq) data were obtained from inflamed and non-inflamed tissues from 170 patients with CD. The samples were clustered based on gene expression profiles using principal coordinate analysis (PCA). Cellular heterogeneity was inferred using CiberSortx, with bulk RNA-seq data. The PCA results displayed two clusters of CD-inflamed samples: one close to (Inflamed_1) and the other far away (Inflamed_2) from the non-inflamed samples. Inflamed_1 was rich in anti-TNF durable responders (DRs), and Inflamed_2 was enriched in non-durable responders (NDRs). The CiberSortx results showed that the cell fraction of activated fibroblasts was six times higher in Inflamed_2 than in Inflamed_1. Validation with public gene expression datasets (GSE16879) revealed that the activated fibroblasts were enriched in NDRs over Next, we used DRs by 1.9 times pre-treatment and 7.5 times after treatment. Fibroblast activation protein (FAP) was overexpressed in the Inflamed_2 and was also overexpressed in the NDRs in both the RISK and GSE16879 datasets. The activation of fibroblasts may play a role in resistance to anti-TNF therapy. Characterizing fibroblasts in inflamed tissues at diagnosis may help to identify patients who are likely to respond to anti-TNF therapy.

A streamlined pipeline based on HmmUFOtu for microbial community profiling using 16S rRNA amplicon sequencing

Microbial community profiling using 16S rRNA amplicon sequencing allows for taxonomic characterization of diverse microorganisms. While amplicon sequence variant (ASV) methods are increasingly favored for their fine-grained resolution of sequence variants, they often discard substantial portions of sequencing reads during quality control, particularly in datasets with large number samples. We present a streamlined pipeline that integrates FastP for read trimming, HmmUFOtu for operational taxonomic units (OTU) clustering, Vsearch for chimera checking, and Kraken2 for taxonomic assignment. To assess the pipeline's performance, we reprocessed two published stool datasets of normal Korean populations: one with 890 and the other with 1,462 independent samples. In the first dataset, HmmUFOtu retained 93.2% of over 104 million read pairs after quality trimming, discarding chimeric or unclassifiable reads, while DADA2, a commonly used ASV method, retained only 44.6% of the reads. Nonetheless, both methods yielded qualitatively similar β-diversity plots. For the second dataset, HmmUFOtu retained 89.2% of read pairs, while DADA2 retained a mere 18.4% of the reads. HmmUFOtu, being a closed-reference clustering method, facilitates merging separately processed datasets, with shared OTUs between the two datasets exhibiting a correlation coefficient of 0.92 in total abundance (log scale). While the first two dimensions of the β-diversity plot exhibited a cohesive mixture of the two datasets, the third dimension revealed the presence of a batch effect. Our comparative evaluation of ASV and OTU methods within this streamlined pipeline provides valuable insights into their performance when processing large-scale microbial 16S rRNA amplicon sequencing data. The strengths of HmmUFOtu and its potential for dataset merging are highlighted.

Development of a Machine Learning Model to Distinguish between Ulcerative Colitis and Crohn's Disease Using RNA Sequencing Data

Crohn’s disease (CD) and ulcerative colitis (UC) can be difficult to differentiate. As differential diagnosis is important in establishing a long-term treatment plan for patients, we aimed to develop a machine learning model for the differential diagnosis of the two diseases using RNA sequencing (RNA-seq) data from endoscopic biopsy tissue from patients with inflammatory bowel disease (n = 127; CD, 94; UC, 33). Biopsy samples were taken from inflammatory lesions or normal tissues. The RNA-seq dataset was processed via mapping to the human reference genome (GRCh38) and quantifying the corresponding gene models that comprised 19,596 protein-coding genes. An unsupervised learning model showed distinct clusters of four classes: CD inflammatory, CD normal, UC inflammatory, and UC normal. A supervised learning model based on partial least squares discriminant analysis was able to distinguish inflammatory CD from inflammatory UC after pruning the strong classifiers of normal CD vs. normal UC. The error rate was minimal and affected only two components: 20 and 50 genes for the first and second components, respectively. The corresponding overall error rate was 0.147. RNA-seq analysis of tissue and the two components revealed in this study may be helpful for distinguishing CD from UC.

Effect of Lactobacillus dominance modified by Korean Red Ginseng on the improvement of Alzheimer's disease in mice

Background

Gut microbiota influence the central nervous system through gut-brain-axis. They also affect the neurological disorders. Gut microbiota differs in patients with Alzheimer's disease (AD), as a potential factor that leads to progression of AD. Oral intake of Korean Red Ginseng (KRG) improves the cognitive functions. Therefore, it can be proposed that KRG affect the microbiota on the gut-brain-axis to the brain.

Methods

Tg2576 were used for the experimental model of AD. They were divided into four groups: wild type (n = 6), AD mice (n = 6), AD mice with 30 mg/kg/day (n = 6) or 100 mg/kg/day (n = 6) of KRG. Following two weeks, changes in gut microbiota were analyzed by Illumina HiSeq4000 platform 16S gene sequencing. Microglial activation were evaluated by quantitative Western blot analyses of Iba-1 protein. Claudin-5, occludin, laminin and CD13 assay were conducted for Blood-brain barrier (BBB) integrity. Amyloid beta (Aβ) accumulation demonstrated through Aβ 42/40 ratio was accessed by ELISA, and cognition were monitored by Novel object location test.

Results

KRG improved the cognitive behavior of mice (30 mg/kg/day p < 0.05; 100 mg/kg/day p < 0.01), and decreased Aβ 42/40 ratio (p < 0.01) indicating reduced Aβ accumulation. Increased Iba-1 (p < 0.001) for reduced microglial activation, and upregulation of Claudin-5 (p < 0.05) for decreased BBB permeability were shown. In particular, diversity of gut microbiota was altered (30 mg/kg/day q-value<0.05), showing increased population of Lactobacillus species. (30 mg/kg/day 411%; 100 mg/kg/day 1040%).

Conclusions

KRG administration showed the Lactobacillus dominance in the gut microbiota. Improvement of AD pathology by KRG can be medicated through gut-brain axis in mice model of AD.

Application of deep learning to predict advanced neoplasia using big clinical data in colorectal cancer screening of asymptomatic adults

BACKGROUND/AIMS

We aimed to develop a deep learning model for the prediction of the risk of advanced colorectal neoplasia (ACRN) in asymptomatic adults, based on which colorectal cancer screening could be customized.

METHODS

We collected data on 26 clinical and laboratory parameters, including age, sex, smoking status, body mass index, complete blood count, blood chemistry, and tumor marker, from 70,336 first-time colonoscopy screening recipients. For reference, we used a logistic regression (LR) model with nine variables manually selected from the 26 variables. A deep neural network (DNN) model was developed using all 26 variables. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of the models were compared in a randomly split validation group.

RESULTS

In comparison with the LR model (AUC, 0.724; 95% confidence interval [CI], 0.684 to 0.765), the DNN model (AUC, 0.760; 95% CI, 0.724 to 0.795) demonstrated significantly improved performance with respect to the prediction of ACRN (p < 0.001). At a sensitivity of 90%, the specificity significantly increased with the application of the DNN model (41.0%) in comparison with the LR model (26.5%) (p < 0.001), indicating that the colonoscopy workload required to detect the same number of ACRNs could be reduced by 20%.

CONCLUSION

The application of DNN to big clinical data could significantly improve the prediction of ACRNs in comparison with the LR model, potentially realizing further customization by utilizing large quantities and various types of biomedical information.

Reversion of Gut Microbiota during the Recovery Phase in Patients with Asymptomatic or Mild COVID-19: Longitudinal Study

Patients with COVID-19 have been reported to experience gastrointestinal symptoms as well as respiratory symptoms, but the effects of COVID-19 on the gut microbiota are poorly understood. We explored gut microbiome profiles associated with the respiratory infection of SARS-CoV-2 during the recovery phase in patients with asymptomatic or mild COVID-19. A longitudinal analysis was performed using the same patients to determine whether the gut microbiota changed after recovery from COVID-19. We applied 16S rRNA amplicon sequencing to analyze two paired fecal samples from 12 patients with asymptomatic or mild COVID-19. Fecal samples were selected at two time points: during SARS-CoV-2 infection (infected state) and after negative conversion of the viral RNA (recovered state). We also compared the microbiome data with those from 36 healthy controls. Microbial evenness of the recovered state was significantly increased compared with the infected state. SARS-CoV-2 infection induced the depletion of Bacteroidetes, while an abundance was observed with a tendency to rapidly reverse in the recovered state. The Firmicutes/Bacteroidetes ratio in the infected state was markedly higher than that in the recovered state. Gut dysbiosis was observed after infection even in patients with asymptomatic or mild COVID-19, while the composition of the gut microbiota was recovered after negative conversion of SARS-CoV-2 RNA. Modifying intestinal microbes in response to COVID-19 might be a useful therapeutic alternative.

Deep Neural Network-Based Prediction of the Risk of Advanced Colorectal Neoplasia

Background/Aims

Risk prediction models using a deep neural network (DNN) have not been reported to predict the risk of advanced colorectal neoplasia (ACRN). The aim of this study was to compare DNN models with simple clinical score models to predict the risk of ACRN in colorectal cancer screening.

Methods

Databases of screening colonoscopy from Kangbuk Samsung Hospital (n=121,794) and Kyung Hee University Hospital at Gangdong (n=3,728) were used to develop DNN-based prediction models. Two DNN models, the Asian-Pacific Colorectal Screening (APCS) model and the Korean Colorectal Screening (KCS) model, were developed and compared with two simple score models using logistic regression methods to predict the risk of ACRN. The areas under the receiver operating characteristic curves (AUCs) of the models were compared in internal and external validation databases.

Results

In the internal validation set, the AUCs of DNN model 1 and the APCS score model were 0.713 and 0.662 (p<0.001), respectively, and the AUCs of DNN model 2 and the KCS score model were 0.730 and 0.667 (p<0.001), respectively. However, in the external validation set, the prediction performances were not significantly different between the two DNN models and the corresponding APCS and KCS score models (both p>0.1).

Conclusions

Simple score models for the risk prediction of ACRN are as useful as DNN-based models when input variables are limited. However, further studies on this issue are warranted to predict the risk of ACRN in colorectal cancer screening because DNN-based models are currently under improvement.

Role of tumour location and surgical extent on prognosis in T2 gallbladder cancer: an international multicentre study

BACKGROUND

In gallbladder cancer, stage T2 is subdivided by tumour location into lesions on the peritoneal side (T2a) or hepatic side (T2b). For tumours on the peritoneal side (T2a), it has been suggested that liver resection may be omitted without compromising the prognosis. However, data to validate this argument are lacking. This study aimed to investigate the prognostic value of tumour location in T2 gallbladder cancer, and to clarify the adequate extent of surgical resection.

METHODS

Clinical data from patients who underwent surgery for gallbladder cancer were collected from 14 hospitals in Korea, Japan, Chile and the USA. Survival and risk factor analyses were conducted.

RESULTS

Data from 937 patients were available for evaluation. The overall 5-year disease-free survival rate was 70·6 per cent, 74·5 per cent for those with T2a and 65·5 per cent among those with T2b tumours (P = 0·028). Regarding liver resection, extended cholecystectomy was associated with a better 5-year disease-free survival rate than simple cholecystectomy (73·0 versus 61·5 per cent; P = 0·012). The 5-year disease-free survival rate was marginally better for extended than simple cholecystectomy in both T2a (76·5 versus 66·1 per cent; P = 0·094) and T2b (68·2 versus 56·2 per cent; P = 0·084) disease. Five-year disease-free survival rates were similar for extended cholecystectomies including liver wedge resection versus segment IVb/V segmentectomy (74·1 versus 71·5 per cent; P = 0·720). In multivariable analysis, independent risk factors for recurrence were presence of symptoms (hazard ratio (HR) 1·52; P = 0·002), R1 resection (HR 1·96; P = 0·004) and N1/N2 status (N1: HR 3·40, P < 0·001; N2: HR 9·56, P < 0·001). Among recurrences, 70·8 per cent were metastatic.

CONCLUSION

Tumour location was not an independent prognostic factor in T2 gallbladder cancer. Extended cholecystectomy was marginally superior to simple cholecystectomy. A radical operation should include liver resection and adequate node dissection.

Accuracy of machine learning for differentiation between optic neuropathies and pseudopapilledema

Background

This study is to evaluate the accuracy of machine learning for differentiation between optic neuropathies, pseudopapilledema (PPE) and normals.

Methods

Two hundred and ninety-five images of optic neuropathies, 295 images of PPE, and 779 control images were used. Pseudopapilledema was defined as follows: cases with elevated optic nerve head and blurred disc margin, with normal visual acuity (> 0.8 Snellen visual acuity), visual field, color vision, and pupillary reflex. The optic neuropathy group included cases of ischemic optic neuropathy (177), optic neuritis (48), diabetic optic neuropathy (17), papilledema (22), and retinal disorders (31). We compared four machine learning classifiers (our model, GoogleNet Inception v3, 19-layer Very Deep Convolution Network from Visual Geometry group (VGG), and 50-layer Deep Residual Learning (ResNet)). Accuracy and area under receiver operating characteristic curve (AUROC) were analyzed.

Results

The accuracy of machine learning classifiers ranged from 95.89 to 98.63% (our model: 95.89%, Inception V3: 96.45%, ResNet: 98.63%, and VGG: 96.80%). A high AUROC score was noted in both ResNet and VGG (0.999).

Conclusions

Machine learning techniques can be combined with fundus photography as an effective approach to distinguish between PPE and elevated optic disc associated with optic neuropathies.

Correction: A deep learning model for the detection of both advanced and early glaucoma using fundus photography

[This corrects the article DOI: 10.1371/journal.pone.0207982.].

A deep learning model for the detection of both advanced and early glaucoma using fundus photography

Purpose

To build a deep learning model to diagnose glaucoma using fundus photography.

Design

Cross sectional case study Subjects, Participants and Controls: A total of 1,542 photos (786 normal controls, 467 advanced glaucoma and 289 early glaucoma patients) were obtained by fundus photography.

Method

The whole dataset of 1,542 images were split into 754 training, 324 validation and 464 test datasets. These datasets were used to construct simple logistic classification and convolutional neural network using Tensorflow. The same datasets were used to fine tune pre-trained GoogleNet Inception v3 model.

Results

The simple logistic classification model showed a training accuracy of 82.9%, validation accuracy of 79.9% and test accuracy of 77.2%. Convolutional neural network achieved accuracy and area under the receiver operating characteristic curve (AUROC) of 92.2% and 0.98 on the training data, 88.6% and 0.95 on the validation data, and 87.9% and 0.94 on the test data. Transfer-learned GoogleNet Inception v3 model achieved accuracy and AUROC of 99.7% and 0.99 on training data, 87.7% and 0.95 on validation data, and 84.5% and 0.93 on test data.

Conclusion

Both advanced and early glaucoma could be correctly detected via machine learning, using only fundus photographs. Our new model that is trained using convolutional neural network is more efficient for the diagnosis of early glaucoma than previously published models.

WITHDRAWN: Application of deep learning to predict advanced neoplasia using big clinical data in colorectal cancer screening of asymptomatic adults

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Abstract 2143: IL-6 mediated signaling regulates cytotoxic effect of Burkitt lymphoma cells by combined treatment of Danusertib and BKM120

Even though Burkitt Lymphoma is relative has a good response to combined treatment, some part of outcome of chemotherapy is very poor. One of the obstacles is the chemoresistance due to several cytokines which are released from stromal cells. The effects of either Danusertib or BKM120 on Namalwa and BJAB, respectively, were different. On Namalwa the IC 50 of Danusertib was 24.64 µM (72 h) and BKM120 was 12.44 µM (72h). On BJAB the IC 50 of Danusertib was 6.63 µM (72h) and BKM120 was 1.42 µM (72h). But in the combined treatment, we found that BJAB showed less sensitive than Namalwa, the IC 50 on Namalwa was Danusertib 8.33 µM+ BKM120 2.08 µM (72h) and on BJAB was Danusertib 20.36 µM+ BKM120 5.09 µM (72h). To figure out the resistant pattern of these two cell lines we performed 3 steps treatment with 16 µM Danusertib and 4 µM BKM120, every step we culture 1.5×105/mL cells in 24hours first, and then treated with combined inhibitors 48 hours. We found that although Namalwa was sensitive to combined treatment at the first step, it was more easily to become resistant to combined treatment. To confirm the resistant pattern, co-culture system was used to identify what kinds of cytokines are involving in the chemoresistance of Burkitt lymphoma. We found that IL-6 was induced with stromal cell including inflammatory cytokines when cells were co-cultured with stromal cells. Also, IL-6 mediated signaling pathway such as JAK/STATIL-6 and AKT pathway, was activated by IL-6 and sIL-6. We suggest that IL-6 mediated signaling could mediate signaling regulates cytotoxic effect of Burkitt lymphoma cells by combined treatment of Danusertib and BKM120 as well as inflammatory effects may regulate the response of chemotherapeutic treatment.

Citation Format: Jun Liu, Kwang-Sung Ahn, Jun-Shik Hong, Sung-Soo Yoon. IL-6 mediated signaling regulates cytotoxic effect of Burkitt lymphoma cells by combined treatment of Danusertib and BKM120 [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 2143.

Abstract 384: The implications of splicing variant of AIMP2 lacking exon 2 among various cancer types: An analysis of the ICGC/TCGA database and clinical validation

Aminoacyl-tRNA synthetase interacting multifunctional proteins (AIMP) is the multiple tRNA synthetase complex protein called the multi-tRNA complex (MRC). In cancer, the splicing variant of AIMP2 derives a several signaling cascades, which are crucial for cancer proliferation. Detecting an exon-2 depleted splicing variant (AIMP2-DX2) is an issue of growing importance in cancer therapy. This study suggests the evidence for interrelation between the AIMP2-DX2 and cancer development. We analyzed AIMP2 and AIMP2-DX2 gene expression and their ratio on 7 commercial cancer cell lines and Multiple myeloma patient derived 536MM cell line by RT-PCR and targeted RNA sequencing. Extended this profile, the distribution of AIMP2-DX2/AIMP2 ratio and AIMP2-related major cancer pathways were analyzed using the samples in the ICGC/TCGA database. Over 23 cancer types, 753 samples were used in WTS analysis. In the DEG set analysis, 10 pre-defined major cancer pathways were analyzed among 16 cancer types. Some cancer types, especially acute myeloid leukemia (AML) showed most significant association with AIMP2-DX2 in terms of cancer signaling pathways. We focused on clinical implications of AIMP2-DX2/AIMP2 ratio in the ICGC/TCGA database. 19 AML samples were used, Overall survival (OS) showed that patients with AIMP2-DX2/AIMP2 ratio higher than Q1 shows poor OS and Most of the genes including MEK1/2, ERK, MNK1/2 in this pathway had positive association with AIMP2-DX2/AIMP2 ratio. In colon carcinoma and hepatocellular carcinoma, OS curves had a tendency in a similar way to AML. For the clinical validation of the prognostic value of AIMP2-DX2, 51 AML patients were included in this analysis. The correlation between AIMP2-DX2 expression and survival outcomes was investigated in clinical validation cohort of AML. The AIMP2-DX2-positive group had significantly inferior OS rate and had worse RFS compare to AIMP2-DX2-negative group. Our sequential data shows that the AIMP2-DX2/AIMP2 expression and their ratio can possibly be an indicator to measure malignancy of various cancer types.

Citation Format: Dong Chan Kim, Ryul Kim, Daeyoon Kim, Hyojin Song, Dong-Yeop Shin, Inho Kim, Kwang-Sung Ahn, Nam Hoon Kwon, Sunghoon Kim, Sung-Soo Yoon, Youngil Koh. The implications of splicing variant of AIMP2 lacking exon 2 among various cancer types: An analysis of the ICGC/TCGA database and clinical validation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 384. doi:10.1158/1538-7445.AM2017-384

Abstract 4823: Characterization of newly established WM-1-SNU cell line harboring negative for MYD88 L265P derived from Waldenstrom macroglobulinemia patient's peripheral blood using xenograft model

Waldenstrom macroglobulinemia (WM) is a rare hematologic malignancy that is a lymphoplasmacytic lymphoma a type of B-cell disease. The common characteristics of WM cells are expression of B cell markers, CD19 and CD20 and secretion of monoclonal immunoglobulin (Ig) M. The other critical feature of WM is MYD88 L265P that is found almost 90% patients. MYD88 gene is related with immune response and inflammatory signaling. Many researches are underway about MYD88 L265P role in WM. However, there is a lack of functional studies in the negative for MYD88 L265P in WM due to the absence of the MYD88 L265P negative cell line. Each cell lines represent the heterogeneity and molecular diversity by genetic features, it is important to establish the MYD88 L265P negative WM cell line for elucidating the biological characteristics of WM. Mononuclear cells obtained from patient’s peripheral blood by ficoll separation and were injected to NRG (JAX, USA) mouse via tail vein. After 24 days, mouse sacrificed and extracted bone marrow (BM) cells from mouse tibia by syringe flushing. Mouse BM cells were cultured in Iscove's Modified Dulbecco's Medium (IMDM) supplemented with 20% heat-inactivated FBS, Penicillin-Streptomycin (10,000 U/mL) (Gibco, USA). G-banding was used to confirm the human chromosomes. Sanger sequencing conducted for detecting the MYD88 L265P mutation. Flow cytometry was used for screening cell surface markers and ELISA was used for the detection of immunoglobulin level. For confirm the tumorigenicity of the cell line, we re-injected the cell line to NSG (JAX, USA) mouse by subcutaneously. After 3 weeks, tumor mass and metastatic tissues were cultured in conditioned medium. Tumor cells have had adherent phenotype and human chromosomes were identified by G-banding. MYD88 L265P mutation that genetic signature of WM was not detected both patient’s peripheral blood and established cell line. CD19 and CD20 expressions were not detected, but CD138 highly expression was confirmed about 90%. Lambda and Kappa secretion were not detected in cell culture supernatant. We confirmed the tumorigenicity through re-injection the cell line by subcutaneously. Tumor mass was formed with a 100% probability and metastasis to lung and bone marrow occurred in about 66%. Tumor mass and metastatic tissues were cultured in in vitro and confirmed the reproducibility. In this study, we describe the newly established human WM cell line derived from peripheral blood of the WM patient who negative for MYD88 L265P using xenograft model having unique biological characteristics comparing to MYD88 L265P positive cells that high tumor formation ability and high expression of CD138 and does not secrete IgM.

Citation Format: Hyejoo Park, Youngil Koh, Kwang-Sung Ahn, Hyo Jung Kim, Sung-Soo Yoon. Characterization of newly established WM-1-SNU cell line harboring negative for MYD88 L265P derived from Waldenstrom macroglobulinemia patient's peripheral blood using xenograft model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4823. doi:10.1158/1538-7445.AM2017-4823

MCM7 polymorphisms associated with the AML relapse and overall survival

The minichromosome maintenance complex component 7 (MCM7) encodes a member of MCM complex, which plays a critical role in the initiation of gene replication. Due to the importance of MCM complex, MCM7 gene has been regarded as a candidate gene for cancer development. In the present study, seven MCM7 polymorphisms were genotyped in 344 subjects composed of 103 acute myeloid leukemia (AML) patients and 241 normal controls to examine the possible associations between MCM7 polymorphisms and the risk of AML. MCM7 polymorphisms were not associated with the risk of AML (P > 0.05). However, MCM7 polymorphisms were significantly related to the relapse of AML and overall survival. The rs2070215 (N144S) showed a protective effect to the risk of AML relapse (OR = 0.37; P ^corr = 0.02). In haplotype analyses, the ht1 and ht2 showed significant associations with the risk of AML relapse (P ^corr = 0.02-0.03). In addition, rs1534309 showed an association with the overall survival of AML patients. Patients with major homozygote genotype (CC) of rs1534309 showed a higher survival rate than the patients with other genotypes (CG and GG). The results of the present study indicate that MCM7 polymorphisms may be able to predict the prognosis of AML patients.

Genetic Association of PARP15 Polymorphisms with Clinical Outcome of Acute Myeloid Leukemia in a Korean Population

AIMS

Some members of the poly ADP-ribose polymerase (PARP) protein family have been regarded as targets for the therapeutic inhibition of cancer. Among these PARP genes, poly ADP-ribose polymerase family, member 15 (PARP15) is a candidate gene for cancer development due to its ability to regulate gene transcription and its reported association with apoptosis. The current study investigated the possible association between PARP15 single-nucleotide polymorphisms and the risk of acute myeloid leukemia (AML). In addition, we analyzed the effects of the PARP15 polymorphisms on the clinical phenotypes associated with cytosine arabinose (AraC) chemotherapy in AML patients.

METHODS

Ten PARP15 polymorphisms were genotyped via TaqMan assay in a total of 344 Korean subjects, including 103 AML patients and 241 normal controls. The genetic effects of the polymorphisms on the risk of AML and the clinical phenotypes were analyzed using Statistical Analysis System (SAS) software.

RESULTS

The results from a Cox regression analysis for overall survival revealed that two polymorphisms were associated with increased overall survival and the signal for rs17208928 was retained after correcting for multiple tests (p^corr < 0.05).

CONCLUSIONS

These results suggest the possibility that the PARP15 gene may be a potential therapeutic target in AML patients although much larger scale studies are needed for validation.

Abstract 539: Analysis of genetic alternations in multiple tissue specimens from each patient: Implications for field-effect colon cancerization

Colorectal cancer (CRC) develops through a polyp-to-cancer progression sequence, in which normal colorectal epithelium transforms into an adenoma, which then progresses to cancer via the accumulation of progressive molecular changes, including both genetic and epigenetic alterations. Given that Colon epithelial cells can acquire pro-tumorigenic mutations that are insufficient to cause morphological change, genetic alternations in adjacent tumor tissues are primed to become neoplastic cells. It is known that individuals with a personal history of colon adenomas or cancer are at increased risk for metachronous colon neoplasms. To examine the genetic alternations involving in a polyp-to-cancer progression sequence, whole-transcriptome expression profiling of resected normal tissues (N1 and N3), adenoma (A1 and A2), and colorectal cancer (C1) obtained from individuals was performed. Differentially expressed genes among groups were identified using Subio platform. GATK and haplotypecaller was used to compare the somatic mutations among three different tissues. Tophat, Cufflink, Mev, R was used for determining the expression levels. Splicegrapher and Genomon-fusion was used for identifying the fusion genes. Ordinal regression analysis was performed to characterize site-dependent expression profiles. Gene interaction was examined using String (Open database). All statistical tests were two-sided, except where noted. Expression profile showed that highly expressed genes associated with inflammation were detected in adenoma. Our results indicated that highly expressed genes associated with inflammation were initially found in adenoma tissues and its levels were consistent in carcinoma tissues. Number of somatic mutation was extremely increased in carcinoma tissues when compared to adenoma tissues. The same mutations in KRAS, CDKN2A(p16) and TP53 that were observed in carcinoma tissues. They were also present in normal tissues and adenoma tissues. Disruption of TP53, CDKN2A, and KRAS were all seen as possible initial events in tumorigenesis; the sequence of mutations (the tumor development pathway) differed among lesions. Also, unique somatic mutations were found 17 genes which were not exist in normal tissues. Those somatic mutations were found in carcinoma tissues. The results of fusion gene analysis showed that 9 fusion genes were detected. Four fusion genes (FIIR-RBM2292, ST7-AS1-ST7, MMP11-IGLL5, EXOC4-LOC101928861) was detected in all of tissues. Five fusion genes were found in normal tissues and adenoma tissues. Unique fusion gene in carcinoma tissue was not detected. One explanation for this increased risk could be field cancerization, which is a phenomenon in which the histologically normal tissue in an organ is primed to undergo transformation. Our analysis of genetic alterations in a single patient appears to be promising markers for field cancerization.

Citation Format: Chansu Lee, Sung Noh Hong, Sungjin Kim, Sunghoon Cho, Sohyun Youn, Kwang-Sung Ahn, Young-Ho Kim. Analysis of genetic alternations in multiple tissue specimens from each patient: Implications for field-effect colon cancerization. [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 539.

Abstract 77: Establishment of lung cancer patient derived xenograft model from circulating tumor cells: Identification of somatic mutations associated with metastatic potentials

Carcinoma metastasis is initiated by a subpopulation of circulating tumor cells (CTCs) found in the blood of patients. However, the existence and genetic alternations of metastasis-initiating cells (MICs) among CTCs has not been experimentally demonstrated. The establishment of xenograft model using CTCs should help us to understand the biologic behaviors and genetic alternations of MICs associated the promotion of metastasis. Here, we demonstrate that xenograft model can be established by CTCs obtained from lung cancer patients and somatic mutations analyzed from xenograft model in which MICs develop metastatic tumor. After injecting mononuclear cells of lung cancer patients via tail vein, mouse was sacrificed at four weeks. After primary cultured cells were isolated from mouse lung tissues, the MICs were selected by using FASC sorting (EpCam+) and then re-injected via tail vein. And tumor formations in mouse were examined at 8 weeks. For identifying somatic mutations, target sequencing with NGS was performed in tumor DNA and cell free DNA (CF DNA) of lung cancer patients bloods. Our results indicated that nonsynonymous IDH, EGFR, KIT, ABL1, PTEN, ATM, P53, and SMAD4 were found in both tumor tissues and CF DNA of lung cancer patients’ bloods. IDH and EGFR was alternative homo. Others newly found in CF DNA. For further examination of the biologic behaviors of tumor cells which harvested from xenograft model using CTCs, we cultured primary cells from lung tissues and analyzed the anti-cancer drug resistance. Our results showed that primary cultured cells (BH-007) were resistant against cisplatin and erlotinib. In assay of migration and invasion, BH-007 cells possessed high metastatic potential when compared with A549 and H23 cell lines. These data suggested that several somatic mutations affect the anti-cancer drug resistance in lung cancer patients. Our future researches will include development of patient-derived xenograft models for preclinical testing of novel therapeutics. And we develop the possible integration of CF DNA analysis and PDX model from CTCs in the design of co-clinical studies for testing in individual lung cancer patients.

Citation Format: Chansu Lee, Youngwook Kim, Eunkyung Bae, Sunghoon Cho, Sohyun Youn, Kwang-Sung Ahn, Bong-Seog Kim. Establishment of lung cancer patient derived xenograft model from circulating tumor cells: Identification of somatic mutations associated with metastatic potentials. [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 77.

Abstract 3186: Improved sensitive detection method of FLT3 (FMS-like tyrosine kinase) internal tandem duplication (ITD) mutation using next-generation sequencing technology and nested PCR

Sensitive detection of internal tandem duplication (ITD) mutation of FLT3 is very important in acute myeloid leukemia. To increase detection sensitivity of FLT3-ITD, we developed new detection algorithm using next generation sequencing (NGS) data. We validated results using nested polymerase chain reaction (PCR) methods. We compared results of NGS data, nested PCR and conventional PCR methods.

First, using whole exome sequencing data of 83 AML patients, we applied calling algorithm for FLT3-ITD. Briefly, to detect ITDs with NGS data, the reads are aligned to a reference sequence (UCSC hg19), with BWA which is a read aligner allowing soft-clipping. Some reads can be an indication of the occurrence of ITD and BWA aligns those reads as soft-clipped.

Second, we deigned two types of primer for Nested PCR. The first primer was targeted wildly for between exon14 and exon15 of FLT3 gene. Nested PCR primer was deigned to target previously reported regions which are frequently occurred ITD mutation. PCR reactions of two steps were performed using the PCR primers sequentially.

In these 83 patients, FLT3-ITD was positive only in 7 patients when tested by conventional PCR methods. When NGS detection method was applied, this resulted in positive FLT3-ITD in 11 patients (11/83, 13%). When validation was performed using nested PCR, FLT3-ITD was confirmed in all of 11 patients. Nested PCR detected additional 4 patient positive for FLT3-ITD in this population. For 68 patients, FLT3-ITD was negative by both NGS and nested PCR method. Overall, NGS method improved sensitivity of FLT3-ITD detection by 57% in this population. And the concordance rate of NGS method and nested PCR was 95.2% (79/83).

Then we investigated clinical significance of sensitive FLT3-ITD detection. For this, we performed nested PCR and conventional PCR at the same time in 238 AML patients to detect FLT3-ITD. Positive rate for FLT3-ITD was 20% (48/238) and 10% (24/238) by nested PCR and conventional PCR respectively. When survival analysis was performed, among patients with negative FLT3-ITD result by conventional PCR, patients who showed positive for FLT3-ITD by nested PCR had shorter overall survival compared to those who showed negative for FLT3-ITD by nested PCR. (p = 0.03). This implies that sensitive FLT3-ITD detection using nested PCR is clinically meaningful.

Diagnosis of FLT3-ITD is very important genetic factor, leading a therapeutic direction for AML patient. Here we report that we have developed alternative more sensitive detection methods for FLT3-ITD based on nested PCR and NGS. Sensitive detection of FLT3-ITD was clinically meaningful, suggesting that these methods should be incorporated in a future clinical practice. Also, we want to note that, NGS method is capable of quantifying FLT3-ITD size and amount in AML patients.

Citation Format: Daeyoon Kim, Yoojin Hong, Youngil Koh, Sung-Soo Yoon, Choong-Hyun Sun, Kwang-Sung Ahn, Seungmook Lee, Hongseok Yun, Suyeon Lee. Improved sensitive detection method of FLT3 (FMS-like tyrosine kinase) internal tandem duplication (ITD) mutation using next-generation sequencing technology and nested PCR. [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 3186.

A scientific treatment approach for acute mast cell leukemia: using a strategy based on next-generation sequencing data

Background

Mast cell leukemia (MCL) is the most aggressive form of systemic mastocytosis disorders. Owing to its rarity, neither pathogenesis nor standard treatment is established for this orphan disease. Hence, we tried to treat a patient with MCL based on the exome and transcriptome sequencing results of the patient's own DNA and RNA.

Methods

First, tumor DNA and RNA were extracted from bone marrow at the time of diagnosis. Germline DNA was extracted from the patient's saliva 45 days after induction chemotherapy and used as a control. Then, we performed whole-exome sequencing (WES) using the DNA and whole transcriptome sequencing (WTS) using the RNA. Single nucleotide variants (SNVs) were called using MuTect and GATK. Samtools, FusionMap, and Gene Set Enrichment Analysis were utilized to analyze WTS results.

Results

WES and WTS results revealed mutation in KIT S476I. Fusion analysis was performed using WTS data, which suggested a possible RARα-B2M fusion. When RNA expression analysis was performed using WTS data, upregulation of PIK3/AKT pathway, downstream of KIT and mTOR, was observed. Based on our WES and WTS results, we first administered all-trans retinoic acid, then dasatinib, and finally, an mTOR inhibitor.

Conclusion

We present a case of orphan disease where we used a targeted approach using WES and WTS data of the patient. Even though our treatment was not successful, use of our approach warrants further validation.

Cytidine deaminase polymorphisms and worse treatment response in normal karyotype AML

The cytidine deaminase (CDA) catalyzes the irreversible hydrolytic deamination of the cytarabine (AraC) into a 1-β-D-arabinofuranosyluracil (AraU), an inactive metabolite that plays a crucial role in lowering the amount of AraC, a key chemotherapeutic drug, in the treatment of patients with acute myeloid leukemia (AML). In this study, we hypothesized that CDA polymorphisms were associated with the AraC metabolism for AML treatment and/or related clinical phenotypes. We analyzed 16 polymorphisms of CDA among 50 normal karyotype AML (NK-AML) patients, 45 abnormal karyotype AML (AK-AML) patients and 241 normal controls (NC). Several polymorphisms and haplotypes, rs532545, rs2072671, rs471760, rs4655226, rs818194 and CDA-ht3, were found to have a strong correlation with NK-AML compared with NC and these polymorphisms also revealed strong linkage disequilibrium with each other. Among them, rs2072671 (79A>C), which is located in a coding region and the resultant amino acid change K27Q, showed significant associations with NK-AML compared with NC (P=0.009 and odds ratio=2.44 in the dominant model). The AC and CC genotypes of rs2072671 (79A>C) were significantly correlated with shorter overall survival rates (P=0.03, hazard ratio=1.84) and first complete remission duration (P=0.007, hazard ratio=3.24) compared with the AA genotype in the NK-AML patients. Our results indicate that rs2072671 in CDA may be an important prognostic marker in NK-AML patients.

Abstract 1107: In whole-exome sequencing analysis, alternations of P-selectin glycoprotein ligand 1 (SELPLG) significantly associates with inflammation and survival outcomes

SELPLG is type I transmembrane receptor found on the surface of neutrophils, monocytes, and most lymphocytes. SELPLG interacts with P -selectin mediates the tethering and rolling of neutrophils, monocytes, and/or lymphocytes on endothelial cells. In whole exome sequencing analysis, we found that somatic mutation of SELPLG (2%) was found. Also its alternation (37%) was found in germline control group. rs201851784 of SELPLG polymorphism (43%) was determined in 118 adult AML patients and its polymorphism (12%) was determined in 1000 genome. The prevalence of the rs201851784 polymorphism was significantly different between AML patients and normal control (AA genotype vs. GG + AG genotype). Comparison analysis of SELPLG showed X-squared = 208.4140, df = 1 and p &lt; 2.2e-16. After the IL-6 expression levels among AML patients were detected by ELISA, the allelic status and IL-6 expression on bone marrow serum of AML patients were analyzed. AML patient having A/G alternation was found to be associated with lower levels of IL-6 compared with AML patients having A/A. Those with persistence had higher IL-6 expression levels compared with those with CR in 1st induction (P &lt; 0.05). In addition, there is a significant correlation between levels and SELPLG rs201851784, as analyzed by linear correlation assay. The AA genotype correlated with higher IL-6 levels (P &lt; 0.05). Reverse correlation between SELPLG rs201851784 and IL-6 levels was found. SELPLG rs201851784 and IL-6 levels were also significantly correlated with OS. In conclusion, a polymorphism in the SELPLG gene related to cell dissemination and tissue infiltration is shown for the first time to be associated with susceptibility of AML and the overall survival.

Citation Format: Sunghoon Cho, Chansu Lee, Hyun Choi, Kwang-Sung Ahn, Yongil Koh, Sung-Soo Yoon. In whole-exome sequencing analysis, alternations of P-selectin glycoprotein ligand 1 (SELPLG) significantly associates with inflammation and survival outcomes. [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 1107. doi:10.1158/1538-7445.AM2015-1107

Abstract 4016: c-MET associated with osteogenesis in multiple myeloma patients by induction of MMP9 expression by HGF in BMSCs

HGF-mediated c-MET signaling plays a critical key in the progression of multiple myeloma. That signaling is associated with cell proliferation, drug resistance and osteoblast. In addition dynamic interplay between MM cell and bone marrow stromal cell regulates that signaling activation. The expression level of HGF in bone marrow plasma of MM patients is higher when compared to case control. However, the role of HGF-mediated c-Met was obscure in the progression of MM. In this study, we elucidate the role of c-Met signaling in osteogenesis in MM using co-culture system.

In our previous data, we found that the expression levels of HGF in bone marrow serum of multiple myeloma patients was correlated with the expression levels of OPN and RUNX2. Also, those expression levels were associated with bone lesion. It suggested that HGF might be one of regulators in the progression of osteogenesis. However, mechanisms by HGF-mediated c-MET activation modulate the expression of matrix metalloproteinases still remain unknown. In our study, we found that Our data show that PI3K inhibitor effectively inhibited the MMP9 mRNA expression in both OPN alone treatment and co-treatment with OPN and HGF in BMSCs. Induction of OPN and RUNX2 by HGF in MM cells could be one of the major factors for the progression of MM through interaction of MM cells and BMSCs. We suggested that induction of OPN/MMP9 strongly associated with osteoclast.

For further analysis, we performed co-culture system which MM cells were grown with BMSCs obtained from MM patients’ bone marrow specimen in order to verify the role of HGF mediated c-MET activation in the progression of MM patient's osteogenesis. To explore the detail mechanisms of HGF-mediated osteogenesis, various inhibitors was used and the expression levels of a set of genes was examined using real-time PCR. Subsequently, HGF-mediated c-MET activation was regulated the expression of OPN/MMP-9 via co-effects of PIK3 activation and activation of wnt signaling pathway in BMSCs from bone marrow of MM patients. In conclusion, cross-talk between PI3K/AKT pathway and wnt singaling pathway could be one of the major factors for the progression of MM through interaction of MM cells and BMSCs.

Citation Format: Hyejoo Park, Jeong In Oh, Kwang-Sung Ahn, Youngil Koh, Sung-Soo Yoon. c-MET associated with osteogenesis in multiple myeloma patients by induction of MMP9 expression by HGF in BMSCs. [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 4016. doi:10.1158/1538-7445.AM2015-4016

Abstract 4309: Description of a scientific treatment approach of mast cell leukemia, an aggressive orphan hematologic disorder: strategy based on next-generation sequencing data

Background

Mast cell leukemia (MCL) is the most aggressive form of disorder among systemic mastocytosis. Due to its rarity, neither pathogenesis nor standard treatment is not established for this orphan disease. Hence, we tried to treat a patient with MCL based on the exome and transcriptome sequencing result of the patient's own DNA and RNA.

Brief Case History and Results

In October 2013, an 18-year-old Korean female were diagnosed as MCL after visiting our hospital due to left knee, ankle pain and inguinal lymphadenopathy. C-KIT overexpression was observed by immunohistochemistry. Whole exome sequencing result failed to demonstrate either noticeable single nucleotide variant (SNV) or copy number change. Interestingly, whole transcriptome sequencing (WTS) revealed mutation of KIT S476I, functionality of which is not known. Fusion analysis was performed using WTS data, possibility of RARα-B2M fusion has been arised. However, it was not validated by PCR sequencing. When RNA expression analysis was performed using WTS data, upregulation of PIK3/AKT pathway, which is a downstream of KIT (BAD phosphorylation) and mTOR has been observed.

For the treatment perspective, she failed to achieve complete remission after cytarabine and idarubicin chemotherapy. Based on our WES and WTS result, we first tried all-trans retinoic acid targeting RARα, which failed to demonstrate efficacy. Then, she received dasatinib targeting KIT, which showed transient response for 2 weeks. Now she is under everolimus targeting mTOR pathway and, further treatment with PI3K inhibitor is planned in case of disease progression.

Conclusions

We are demonstrating a case of orphan disease, where we used targeted approach using WES and WTS data of the patient. Final results of our treatment outcome will be uncovered shortly, and utility of this kind of approach is to be validated.

Citation Format: Jeonghwan Youk, Youngil Koh, Ji-Won Kim, Dae-Yoon Kim, Woo June Jung, Kwang-Sung Ahn, Sung-Soo Yoon, Hye Lim Jung. Description of a scientific treatment approach of mast cell leukemia, an aggressive orphan hematologic disorder: strategy based on next-generation sequencing data. [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 4309. doi:10.1158/1538-7445.AM2015-4309

Strain elastography features of epidermoid tumours in superficial soft tissue: differences from other benign soft-tissue tumours and malignant tumours

OBJECTIVE

We evaluated ultrasonographic features of superficial epidermoid tumour with a focus on strain elastography (SE) features that will help in the differential diagnosis of epidermoid tumour from other benign and malignant soft-tissue tumours.

METHODS

We retrospectively evaluated ultrasonographic and SE data of 103 surgically confirmed superficial soft-tissue tumours and tumour-like lesions: 29 cases of epidermoid tumour, 46 cases of other benign tumours and 28 cases of malignant tumour. SE and B-mode imaging were performed at the same time. SE characteristics were assigned into four grades (1-4) according to their elasticity. Interobserver agreement for the four SE scores between the two radiologists was analysed using kappa statistics. We classified each SE finding as a hard lesion (SE Score 3-4) or soft lesion (SE Score 1-2) and compared these findings using the χ(2) test to identify whether a significant difference in mass hardness existed among epidermoid tumour, other benign tumour and malignant tumour.

RESULTS

Overall interobserver agreement according to the four SE scores was moderate (κ = 0.540), and overall agreement for the hardness [soft (Score 1-2) or hard (Score 3-4)] was almost perfect (κ = 0.825). Malignant tumours showed higher SE scores (3-4, hard nature) than did epidermoid tumour or other benign soft-tissue tumours. There were no differences in SE score between epidermoid tumour and other benign tumours.

CONCLUSION

Superficial epidermoid tumour exhibits a softer nature than does malignant tumour but does not have a different SE pattern from other benign tumours.

ADVANCES IN KNOWLEDGE

SE features of epidermoid tumour might be helpful in differentiating from other benign and malignant tumours.

Abstract 1152: Gene profiling of multiple myeloma: MAPK pathway deregulation, which is regulated by PIM-1 and MOS, is associated with relapse within 6 months after autoSCT in MM patients

Substantial advances have been made in understanding the biology of multiple myeloma (MM) through the study of the bone marrow (BM) microenvironment. Dynamic interplay between bone marrow stromal cells (BMSCs) and MM cells regulated the relapsed MM after autologous bone marrow transplantation (ABMT). In this study, we performed gene expression profiling with microarray data to better dissect the molecular phenotypes and prognoses of relapsed multiple myeloma (MM). Using gene expression and clinical data, we applied gene expression signatures reflecting deregulation of oncogenic pathways to highlight molecular changes in bone marrow aspirate from 28 patients with relapsed MM. The patient subgroups were defined according to relapse-free interval, within 6 months versus more than 6 months. The microarray results revealed that dyregulation of MAPK pathway was associated with relapse within 6 months after ABMT. Among them, the expression of PIM-1 gene and MOS gene was higher in samples from patients with relapsed MM than MM cell lines (p=0.0037; p=0.0021). Also, IL-6, sIL-6R, and HGF expression in patients who relapsed within 6 months after ABMT was higher than the patients whose relapse-free interval were longer than 6 months. Treatment of shRNA PIM-1 gene and shRNA MOS gene in U266 and MOLP8 dramatically led to decreasing IL-6/sIL-6R mediated ERK phosphorylation and HGF-mediated MET phosphorylation. Similar results were noted for cluster genes for PIM-1/MOS. Especially, functional analysis of PIM-1 leads to inactivate the MAPK pathway through regulating p38 mediated signaling and Wnt/β-catenin pathway. Recent studies suggested that p38 activity in myeloma inhibits osteoblast differentiation and bone formation, but also enhances osteoclast maturation and bone resorption. p38 regulated the expression and secretion of the Wnt pathway antagonist DKK-1 and the monocyte chemoattractant MCP-1. Conclusionally, Our analysis suggested that MOS gene and PIM-1, which regulates MAPK pathway, is a noble prognostic marker for relapse of MM. The importance of the PIM-1-MOS-MAPK pathway as a prognostic marker in relapsed MM should be reassessed in the novel therapeutic agent era.

Citation Format: Woo June Jung, Kwang-Sung Ahn, Chansu Lee, Youngil Koh, Hyun Jung Lee, Hyo Jung Kim, Hwi-Joong Yoon, Sung-Soo Yoon. Gene profiling of multiple myeloma: MAPK pathway deregulation, which is regulated by PIM-1 and MOS, is associated with relapse within 6 months after autoSCT in MM patients. [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 1152. doi:10.1158/1538-7445.AM2014-1152

Abstract 1695: CKD-581, a novel histone deacetylase inhibitor, synergistically enhances Bortezomib cytotoxicity in multiple myeloma cells

For Multiple Myeloma (MM), better anti-MM therapies need to be developed in order to treat refractory, relapsed, and newly diagnosed MM. Recently, Histone deacetylase inhibitors (HDACIs) as a combined drug with bortezomib have been evaluated for the treatment of MM. In this study, we examined to determine the anti-MM effects of a novel HDACI, CKD-581, in MM cells. We treated MM cells with CKD-581 either alone or in combination with Bortezomib. Treatments of 9 different MM cell lines with CKD-581 resulted in dose-and time-dependent growth arrest accompanied by the induction of p21 expression and the reduction of cMYC. CKD-581 enhanced Bortezomib-induced cell growth arrest and apoptosis by further reduction of NF-kB mediated cell signaling pathway, which resulted in functional blockage of ubiquitination-related genes. CKD-581, alone or combined with bortezomib, also abrogated the G2/M cell cycle checkpoint, potentially through the suppression of CHK1 expression as well as synergic growth arrest via induction/reduction of CHKs and cMYC, as revealed in combined treatment of CDK-581 and bortezomib. CKD-581-induced sensitization of Bortezomib resistant MM cells to cytotoxic treatment resulted in an increased number of apoptotic cells as judged by annexin V-positivity and the presence of cleaved caspase-3. In addition, CKD-581 effectively induced the apoptosis of MM cells, which were co-cultured with BMSCs obtained from MM patients' BM. CKD-581 effectively inhibited the secretion of IL-6/sIL-6 and HGF, involved in bone lesion, from MM patients' BMSCs. In animal model, CKD-581 was well tolerated, and resulted in tumor growth inhibition and prolonged survival. In summary, the HDAC inhibitor, CKD-581, is a promising therapeutic agent for MM patients, especially when used in combination with Bortezomib.

Citation Format: Chansu Lee, Kwang-Sung Ahn, Woo June Jung, Youngil Koh, Hyo Jung Kim, Hyun Jung Lee, Hwi-Joong Yoon, Sung-Soo Yoon. CKD-581, a novel histone deacetylase inhibitor, synergistically enhances Bortezomib cytotoxicity in multiple myeloma cells. [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 1695. doi:10.1158/1538-7445.AM2014-1695

Establishment and characterization of bortezomib-resistant U266 cell line: constitutive activation of NF-κB-mediated cell signals and/or alterations of ubiquitylation-related genes reduce bortezomib-induced apoptosis

Bortezomib has been known as the most promising anti-cancer drug for multiple myeloma (MM). However, recent studies reported that not all MM patients respond to bortezomib. To overcome such a stumbling-block, studies are needed to clarify the mechanisms of bortezomib resistance. In this study, we established a bortezomib-resistant cell line (U266/velR), and explored its biological characteristics. The U266/velR showed reduced sensitivity to bortezomib, and also showed crossresistance to the chemically unrelated drug thalidomide. U266/velR cells had a higher proportion of CD138 negative subpopulation, known as stem-like feature, compared to parental U266 cells. U266/velR showed relatively less inhibitory effect of prosurvival NF-κB signaling by bortezomib. Further analysis of RNA microarray identified genes related to ubiquitination that were differentially regulated in U266/velR. Moreover, the expression level of CD52 in U266 cells was associated with bortezomib response. Our findings provide the basis for developing therapeutic strategies in bortezomib-resistant relapsed and refractory MM patients.

Negative regulation of signal transducer and activator of transcription-3 signalling cascade by lupeol inhibits growth and induces apoptosis in hepatocellular carcinoma cells

Background:

Constitutive activation of signal transducer and activator of transcription signalling 3 (STAT3) has been linked with survival, proliferation and angiogenesis in a wide variety of malignancies including hepatocellular carcinoma (HCC).

Methods:

We evaluated the effect of lupeol on STAT3 signalling cascade and its regulated functional responses in HCC cells.

Results:

Lupeol suppressed constitutive activation of STAT3 phosphorylation at tyrosine 705 residue effectively in a dose- and time-dependent manner. The phosphorylation of Janus-activated kinases (JAKs) 1 and 2 and Src was also suppressed by lupeol. Pervanadate treatment reversed the downregulation of phospho-STAT3 induced by lupeol, thereby indicating the involvement of a phosphatase. Indeed, we observed that treatment with lupeol increased the protein and mRNA levels of SHP-2, and silencing of SHP-2 abolished the inhibitory effects of lupeol on STAT3 activation. Treatment with lupeol also downregulated the expression of diverse STAT3-regulated genes and decreased the binding of STAT3 to VEGF promoter. Moreover, the proliferation of various HCC cells was significantly suppressed by lupeol, being associated with substantial induction of apoptosis. Depletion of SHP-2 reversed the observed antiproliferative and pro-apoptotic effects of lupeol.

Conclusions:

Lupeol exhibited its potential anticancer effects in HCC through the downregulation of STAT3-induced pro-survival signalling cascade.

Copy number variations in normal karyotype acute myeloid leukaemia and their association with treatment response

Copy number variation (CNV) has been reported to be associated with chemotherapy response, which affects disease prognosis. Here, we determined the frequency of genome-wide cytogenetic CNV aberrations in Korean patients with normal karyotype (NK) acute myeloid leukaemia (AML) and tested whether these genomic variations contribute to differences in Ara-C and anthracycline-based chemotherapy responses. Bone marrow aspirates and blood from 30 previously untreated de novo NK-AML patients were provided at the time of diagnosis for copy number analysis. Possible associations between cytogenetic aberrations and clinical parameters were analysed. CNVs were identified in 23 (76.7%) of the 30 cases tested. Multivariate analyses controlled for other clinical co-variates showed that patients having copy number loss had a decreased probability of complete remission (OR, 0.015 [95% CI, 0-0.737], p = 0.035). Patients who had a copy number gain of more than four regions tended to have shorter event-free survival (EFS) (p = 0.083) with multivariate analysis showing that CNV increase is an independent predictive factor for shorter EFS (HR, 22.104 [95% CI, 1.644-297.157], p = 0.020). In addition, we identified candidate genes that may be involved in Ara-C and anthracycline drug response in Korean patients with NK-AML. These results suggest that CNVs may affect the success of Ara-C and anthracycline-based chemotherapy in Korean patients with NK-AML.

Abstract 1518: Multiple myeloma cells cross talk with bone marrow stroma lead to induction of DKK1 expression and produce bortezomib resistance

The importance of the micro-environment in tumor progression is now well established. Dynamic interaction between multiple myeloma (MM) cells and bone marrow stromal cells (BMSCs) plays critical role in the progression of MM including drug response and bone erosion. Firstly, we found that DKK1 expression was statistically increased in MM cells (MOLP8, KMS12BM, KMS12PE, NCIH929, LP1, MOLP2, EJM, U266, RPMI8226, and 536MM, respectively) co-cultured with BMSCs obtained from MM patients when compared to MM cells alone (p&lt;0.05). Also, MM cells co-cultured with BMSCs were significantly more resistant against 25 nM bortezomib than MM cells alone (p&lt;0.05). We, therefore, established a bortezomib-resistant cell line using U266 cells (U266/velR), and explored the characteristics of U266/velR cells. Cytotoxic effect of bortezomib in U266/velR was 1.5 folds lower than U266 cells, and the cross-resistance against thalidomide was observed. DKK1 expression in U266/velR was higher than that in parental cells. We found that elevated levels of p-p65 were detected in U266/velR, and the degree of p65 and I-κB expression levels reduced by bortezomib was different between U266/velR and U266. Elevated levels of p-p65/p65 were effectively suppressed by treating with NF-κB activator inhibitor (6-aminoquinazoline). Also, combined treatment of bortezomib and 6-aminoquinazoline reduced the expression of DKK1 in co-culture of U266 cells and BMSCs. The expression of HGF in CD138− fractions of MM bone marrow cells was higher than that in its CD138+ fractions. Whereas, IL-6 and OPN in CD138+ fraction of MM bone marrow cells was higher compared to its CD138− fractions. In co-culture of U266 and BMSCs, IL-6, OPN and HGF was dramatically increased compared to U266 alone and BMSC alone (p&lt;0.01; p&lt;0.05). Taken together, cytokines and growth factor regulated by dynamic interplay between MM cells and BMSCs contributes the bortezomib response and bone erosion.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1518. doi:1538-7445.AM2012-1518

Abstract 1527: CD44v9 involving in multiple myeloma cells adhesion to bone marrow stromal cell promotes bone erosion by augmenting the activation of HGF-receptor/cMet

The main aim of our study is to determine the significance of the stromal microenvironment in the malignant behavior of multiple myeloma cells. The stroma-derived growth factors/cytokines and hyaluronan act in autocrine/paracrine ways with their receptors, including receptor-tyrosine kinases and CD44 variants (CD44v), to potentiate and support multiple myeloma cell survival. In this study, we found that CD44s and CD44 variants were differentially expressed between fraction of CD138+ fraction and CD138- fraction. Expression levels of CD44v6, CD44v9, and CD44v10, respectively, correlated with bone erosion (p=0.029, p=0.013, p=0.032), suggesting that CD44 variant molecules are involved in multiple myeloma progression. Binding studies using CD44 isoform specific reagents showed that CD44v6 and CD44v9 were involved in binding to bone marrow stromal cells, but not to in vitro synthesized ECM. In 3D culture, CD44v6 and CD44v9-mediated plasma cell binding resulted in a significant induction of HGF secretion by bone marrow stromal cells. CD44v6 and CD44v9-mediated plasma cell binding significantly induces PI3K/Akt via activation the Src-kinase Lyn. In bone marrow serum of MM patients, the expression levels of IL-6, OPN, and hepatocyte growth factor (HGF), respectively, statistically correlated with bone erosion of MM patients (p=0.021, p=0.001, p=0.036). HGF derived from bone marrow stromal cells with multiple myeloma cells stimulates CD44 signaling via activation of HGF-receptor/cMet. Specific CD44 shRNA suppresses HGF-mediated CD44 signaling. Taken together, the role of CD44 variants in adhesion induced HGF- secretion may explain the previously observed correlation between CD44 variants expression and adverse prognosis in multiple myeloma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1527. doi:1538-7445.AM2012-1527

Abstract 300: Blockage of OPN induction via HGF/cMET signaling in multiple myeloma cells suppresses both MMP9 expression and RUNX2 expression of BMSCs associating with bone erosion of MM patients

Dynamic interaction between multiple myeloma cells (MM) and bone marrow stromal cells plays critical roles in progression of MM. Hepatocyte growth factor (HGF), one of these factors, as a c-Met ligand, activates mitogenic activation protein kinase (MAPK). OPN binds with integrins and CD44 variants and activates cell signaling involved in invasiveness, angiogenesis and bone remodeling. Increasing lines of evidence provide that HGF and OPN, respectively, associate with the progression of MM. However, the role of HGF in MM largely remains unknown. In bone marrow serum of MM patients, HGF expression correlated with OPN expression (p=0,0095), suggesting that HGF derived from bone marrow stromal cells stimulates OPN expression in MM cells. Firstly, we found that expression levels of OPN in HFG-treated MM cells (fraction of CD138+ cells) obtained from MM patients was higher than either HFG-treated bone marrow stromal cells or HFG-treated MM cells (fraction of CD138- cells). Also, induction of DKK1 by HGF, suggesting the inhibition of osteogenesis, was found in U266 cells and RPMI8226, Both HGF-mediated MAPK and PI3K/AKT results in activating NF-kB and increasing OPN expression and DKK1. Those expressions were effectively down-regulated in U266 cells transfected with shRNA c-MET. RUNX2 mRNA and MMP-9 mRNA was increased in bone marrow stromal cells (BMSCs) treated with OPN. In addition, combined cMET inhibitor and PI3K inhibitor effectively inhibited the RUNX2 and the MMP9 mRNA expression in both OPN alone treatment and co-treatment with OPN and HGF in BMSCs. Taken together, since Induction of OPN and DKK1 by HGF in MM cells could be one of the major factors for the progression of MM through interaction of MM cells and BMSCs, blockage of HGF/cMET signaling leading to increasing levels of OPN and DKK1 may help to prevent from progressing bone erosion of MM patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 300. doi:1538-7445.AM2012-300

A gene-specific primer extension and liquid bead array system for killer-cell immunoglobulin-like receptor genotyping

A simple and accurate method for killer-cell immunoglobulin-like receptor (KIR) genotyping is developed using KIR gene-specific primer extension (GSPE) followed by bead array hybridization (GSPE method). After amplification of exons 4, 5, and 9, KIR GSPE and bead array hybridization were performed to verify the presence or absence of 16 KIR subfamilies. GSPE method was validated with natural killer/KIR reference panel I consisting of 48 cell types provided by 13th International Histocompatibility Working Group (IHWG) and genomic DNA from 17 peripheral blood cells, 8 cell lines, and 8 buccal cells. The results of reference panel from GSPE method were 100% concordant with the IHWG reference typing information. All genomic DNAs except reference panel were typed for KIR genes with sequence-specific primer methods and showed 100% identical typing results using this novel system. In addition, GSPE method can obtain results in 8 h from DNA with 10 ng genomic DNA in a 96-well-based assay format.

Abstract 3381: AhR shRNA effectively suppresses B(a)P-mediated induction of slug modulating tumor invasion and cell migration in non small cell lung cancer cell line

Exposure of B(a)P on lung tissue have been implicated in cancer development and its progression. Even though increasing evidences have been reported adversely effects of B(a)P in tumor progression, mechanism by which exposure of Bap on lung cancer cells increases the metastatic potentials still remains unknown. Here, we show that B(a)P triggers a marked morphological changes of Non Small Cell Lung Cancer (NSCLC) cells. These B(a)P-mediated effects are mimicked by decreasing E-cadherin resulting in loosening cell-cell contacts and by increasing Slug expression resulting in inducing epithelial mesenchymal transition (EMT). In case that NCSCLC cell was prolonged exposed to B(a)P, B(a)P-exposed cells showed increasing cell motility and invasion. They correlate with B(a)P-mediated phosphorylations of JNK and p38. And they are reverted by treatment with their inhibitors. In transient transfection analysis, H1299-snail2, constitutively expressing snail2, increased the cell motility and invasion. AhR shRNA effectively suppresses either B(a)P-mediated tumor invasion and induction of snail2. And suppression of E-caherin was found in H1299-snail2. Results of immunohistochemical stain revealed that Slug strongly expressed in invasive foci of Non Small Cell Lung Cancer tissue. Our results suggested that NSCLC cells prolonged exposed to B(a)P increased cell motility and invasiveness via regulation of expression of Sanil2 by exposure of B(a)P on NSCLC cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3381. doi:10.1158/1538-7445.AM2011-3381

Preoperative inflammation is a prognostic factor for gallbladder carcinoma

BACKGROUND

Inflammation frequently accompanies gallbladder carcinoma (GBC), but its impact on outcome is unclear. The present study investigated the impact of concomitant inflammation on survival of patients with GBC.

METHODS

All patients undergoing surgery for GBC between October 2003 and May 2009 were identified retrospectively from a prospectively collected database. Patients were classified according to whether preoperative inflammation was present (65 patients) or not (23).

RESULTS

A total of 88 patients were enrolled. There were no differences in sex, mean age, tumour node metastasis (TNM) stage and radicality of resection between the two groups. The overall 3-year survival rate was lower in patients with preoperative inflammation than in those without (33 versus 73 per cent; P = 0·001). In univariable analysis, preoperative inflammation, T, N and M category, TNM stage, radicality of surgery and tumour differentiation were significant prognostic factors. The presence of preoperative inflammation (hazard ratio (HR) 2·38, 95 per cent confidence interval 1·04 to 5·43), lymph node metastases (HR 5·23, 1·05 to 26·09) and R1 or R2 resection (HR 3·77, 1·47 to 9·72) were independent prognostic factors for poor survival.

CONCLUSION

The presence of preoperative inflammation is an independent prognostic factor for poor survival in patients with GBC.

RNA interference-directed caveolin-1 knockdown sensitizes SN12CPM6 cells to doxorubicin-induced apoptosis and reduces lung metastasis

Human renal cell carcinoma (HRCC) is characterized by a high level of resistance to all treatment modalities. Therefore, the investigation of global gene expression in HRCC might help understand its biologic behavior and develop treatment strategies. Using cDNA microarray analysis, we initially compared gene expression profiles between HRCCs and adjacent normal tissues, and found that 87 were up-regulated and 127 genes were down-regulated. Next, a subset of genes, twofold differentially expressed, were validated by Northern blotting. Unexpectedly, caveolin-1, a gene reported to be a tumor suppressor gene, was found to be up-regulated in HRCC tissues. Expression level of caveolin-1 in SN12CPM6 (high metastatic clone) was higher than in SN12C (low metastatic clone), and SN12CPM6 was more resistant to doxorubicin (DXR) than SN12C. Caveolin-1 gene was slightly induced in surviving SN12C cells after DXR treatment. Furthermore, SN12CPM6-siCav1 cells, which were transfected with siRNA of cavelon-1 gene, were more sensitive to DXR, compared to SN12CPM6, but reduction of caveolin-1 gene expression did not affect tumor formation in subcapsule of kidney and lung metastasis. On the other hand, induction of caveolin-1 gene affected the production of lung metastasis under anti-cancer drug treatment: the incidence of pulmonary metastasis was significantly lower in SCID mice injected with SN12CPM6-siCav1 cells, and the number of pulmonary nodules decreased significantly (p = 0.0004). The above results together suggest that caveolin-1 may confer a growth advantage to cancer cells during DXR chemotherapy and surviving HRCC cells eventually might develop lung metastasis.

Slug suppression induces apoptosis via Puma transactivation in rheumatoid arthritis fibroblast-like synoviocytes treated with hydrogen peroxide

Inadequate apoptosis contributes to synovial hyperplasia in rheumatoid arthritis (RA). Recent study shows that low expression of Puma might be partially responsible for the decreased apoptosis of fibroblast-like synoviocytes (FLS). Slug, a highly conserved zinc finger transcriptional repressor, is known to antagonize apoptosis of hematopoietic progenitor cells by repressing Puma transactivation. In this study, we examined the expression and function of Slug in RA FLS. Slug mRNA expression was measured in the synovial tissue (ST) and FLS obtained from RA and osteoarthritis patients. Slug and Puma mRNA expression in FLS by apoptotic stimuli were measured by real-time PCR analysis. FLS were transfected with control siRNA or Slug siRNA. Apoptosis was quantified by trypan blue exclusion, DNA fragmentation and caspase-3 assay. RA ST expressed higher level of Slug mRNA compared with osteoarthritis ST. Slug was significantly induced by hydrogen peroxide (H2O2) but not by exogenous p53 in RA FLS. Puma induction by H2O2 stimulation was significantly higher in Slug siRNA-transfected FLS compared with control siRNA-transfected FLS. After H2O2 stimulation, viable cell number was significantly lower in Slug siRNA-transfected FLS compared with control siRNA-transfected FLS. Apoptosis enhancing effect of Slug siRNA was further confirmed by ELISA that detects cytoplasmic histone-associated DNA fragments and caspase-3 assay. These data demonstrate that Slug is overexpressed in RA ST and that suppression of Slug gene facilitates apoptosis of FLS by increasing Puma transactivation. Slug may therefore represent a potential therapeutic target in RA.

Establishment of a new Glivec-resistant chronic myeloid leukemia cell line, SNUCML-02, using an in vivo model

OBJECTIVE

In this study, we report a newly established chronic myeloid leukemia (CML) cell line, SNUCML-02, which is resistant to imatinib and describe its biological characteristics.

MATERIALS AND METHODS

Mononuclear cells were obtained from the bone marrow of a CML patient in blast crisis and were cultured in Dulbecco's modified Eagle's medium/F12 containing 20% fetal bovine serum. After 2 months of primary culture, these cells were injected into nonobese diabetic/severe combined immune-deficient mice via tail vein. Eight weeks after injection, mice were sacrificed and ex vivo culture was performed from the bone marrow cells isolated from the mice. The established cell line was named as SNUCML-02 and the biological features were characterized by cytogenetic analysis, fluorescence in situ hybridization, reverse transcriptase polymerase chain reaction, sequencing analysis, cell proliferation assay, and Western blot analysis.

RESULTS

Cytogenetic studies using conventional G-banding and fluorescent in situ hybridization of SNUCML-02 demonstrated classical Philadelphia chromosome, (9;22)(q34;q11.2), and other abnormalities, such as add(11)(q23), +19 and +der(9;22). SNUCML-02 has the same BCR-ABL fusion transcript as was seen in K562 cells, but has no mutations in the ABL kinase domain. SNUCML-02 was more resistant to imatinib (STI571, Gleevec, Glivec) than other CML cell lines (K562, Kcl22, and BV173). SNUCML-02 has constitutive activation of extracellular signal-regulated kinase phosphorylation. In addition, interleukin-3 induced c-ABL phosphorylation and constitutively enhanced extracellular signal-regulated kinase phosphorylation was not inhibited by imatinib in SNUCML-02.

CONCLUSION

SNUCML-02 is a new established cell line with a relatively high level of resistance to imatinib, which is useful for investigating the pathogenesis of CML progression, and will be useful in developing optimal therapeutic strategies for this ailment.

Abstract 5476: gp130 knockdown by short hairpin RNA synergistic effect of bortezomib induced apoptosis in multiple myeloma cells

Although bortezomib, one of targeted anti-cancer drugs, effectively suppresses the growth of multiple myeloma (MM) cells via inactivation of NF-κB, activation of IL-6 mediated cell signaling could be suppressed bortezomib mediated apoptosis. Previously we found that the expression levels of IL-6 and sIL-6R in MM patient's bone marrow serum was higher than control. A set of reports suggested that those levels affect the progression of MM. In addition, bortezomib mediated apoptosis directly associated with the activities of NF-κB in MM cells. However, at present, their precise roles, especially IL-6 mediated cell signaling associating with NF-κB activation, in the progression of MM and therapeutic response to anti-cancer treatment still remain largely unknown. In this study, U266 cells treated with combination of IL-6 and sIL-6R showed the prolongation of the phosphorylation of ERK and STAT3 when compared with IL-6 alone. Transient transfection of gp130 shRNA in MM cells (MM/gp130 shRNA) showed inhibition of IL-6/sIL-6R induced ERK and STAT3 phosphorylation. Next, the effect of IL-6 and sIL-6R in an anti-myeloma agent, bortezomib, was investigated. In cell proliferation assay, U266 and RPMI8226 cells exposed to IL-6 and sIL-6R were decreased induction of apoptosis by bortezomib. In addition, MM/gp130 shRNA cells treated with bortezomib showed significantly inhibited c-Myc and cyclinD1 and increased apoptosis by borteozomib compared with parental cells. In this study indicated that the synergic activation of ERK and STAT3 phosphorylation as the result of IL-6 with sIL-6R could diminished by knockdown of gp130 and its effect could be potentiated the apoptotic efficacy of bortezomib in MM cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5476.

Abstract 1543: Up-regulation of CD52 enhances the resistance against bortezomib in multiple myeloma cells

Bortezomib has excellent clinical activity in patients with multiple myeloma (MM). Clinical efficacy has been hampered by the emergence of drug-resistance phenomena. Verification of molecular mechanism by which resistance emerges is crucial for improved treatment outcome in MM. In this study, we established bortezomib resistance MM cells (U266/velR) and examined the biologic characteristics. In microarray analysis, 294 genes expressions were changed more than two-fold or greater and seven putative genes were selected by further analyzing microarray dataset. Those gene expressions between U266/velR and its control were confirmed using real-time RT-PCR. Among them, CD52, the lymphocyte surface marker, could be a target molecule to overcome bortezomib resistance. CD52 gene expression was examined in 6 different MM cell lines. Its expression was detected in U266, ARH77, and HS-sultan, but not in RPMI8226, IM9 and 536MM. The expression level of CD52 was correlated to the response of Bortezomib sensitivity. FASC analysis showed that CD52+ populations in U266/velR were 2.7 fold higher than those in control. When U266 cells were serially treated with Bortezomib, CD52 expression was gradually increased. In transfection analysis using full length cDNA of CD52 gene, transfected RPMI8226 cells were more resistant than parental cell. Our results suggested that Alemtuzumab was proposed as a therapeutic agent in bortezomib resistant myeloma patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1543.

Abstract 5270: Activation of B-raf by TCDD effects on chemotherapeutic resistance and potent inhibition of TCDD mediated tumor invasion of papillary thyroid cancer cells by PD98059

The BRAF mutation (V599E) is the most common oncogenic genetic alteration in PTC and, through aberrant activation of the MAPK pathway, can initiate the development and promote the progression of PTC. Constitutive activation of the MAPK pathway through genetic alterations, including RAS and B-type RAF (BRAF) mutations, is common in human cancers and is associated with cell malignant transformation and aggressiveness, implicating that targeted inhibition of the MAPK pathway may potentially be an effective therapy for human cancers. AhR receptor ligands such as TCDD are known to activate mitogen activated protein (MAP) kinases and stress-activated protein kinase/c-Jun NH2-terminal kinase. Here we report that PD98059 successfully inhibits cisplatin-induced apoptosis. And induction of phospho-JNK and phospho-ERK-1/2 were noted when SNU-790 cells were treated with 1 nM TCDD. In in vitro tumor invasion assay, TCDD-induced tumor invasion was reduced by either PD98059 or JNK II inhibitor. PD98059 effectively inhibited TCDD-induced tumor invasion when compared to control. The transcription luciferase reporter system demonstrated that PD98059 effectively reduced AP-1 activity when compared to control. The levels of MMP-2 and MMP-9 mRNA expression were reduced slightly by treatment with PD98059. We conclude a significant association of tumor progression in BRAF mutant PTC with the exposure of TCDD. Our findings suggest that MEK inhibitor (PD98059) may function as a small molecule inhibitor of tumor invasion and may provide novel mechanistic insights into the potential therapy for human ATC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5270.