Browsing Over 164 Presentations
83P - Comparing clonality between components of combined hepatocellular carcinoma and cholangiocarcinoma by targeted sequencing (ID 80)
- Nara Yoon (Incheon, KR)
Abstract
Background
Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a very rare tumor. It has two different components (hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC)) in a single mass. Although several studies have determined genetic characteristics of cHCC-CC, Next-generation sequencing (NGS) data for comparing clonality of cHCC-CC are currently unavailable.
Methods
We selected four cHCC-CC cases and micro-dissected HCC, CC, and normal components separately from each case. DNA and RNA were isolated from each sample and sequenced by Oncomine Comprehensive Panel (OCP) interrogating 143 cancer genes using Ion S5 XL sequence platform. Genetic features of HCC and CC from each patient were compared.
Results
All cases successfully produced NGS data. Two cases demonstrated different mutations between HCC and CC components (biclone) while two cases shared the same mutations between two components (monoclone). SNPs of TP53 (4/4) and PTEN (1/4) and gene amplifications of MET (1/4), c-MYC (1/4), and CDK6 (1/4) were found in CC component. In HCC component, SNPs of TP53 (3/4), PTEN (1/4) and CTNNB1 (1/4) and CCND1 amplification (1/4) were detected. Two biclonal cases showed histologically distinguished border between HCC and CC components with or without intermediate cell foci. Two monoclonal cases showed histologically ambiguous border between HCC and CC components with more intermingled pattern than biclonal cases.
Conclusions
We compared genetic compositions of HCC and CC components and matched clonality with histologic feature in cHCC-CC using targeted sequencing. Two (50%) of four cases had different clones between HCC and CC components with more distinguished histologic features than monoclonal cases. Considering such heterogeneity, partly sequencing is recommended for cHCC-CC, especially in those who have histologically distinguished HCC and CC components regardless of the presence of intermediate component.
Legal entity responsible for the study
Nara Yoon.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Presentation 1 (ID 247)
Switching a cold into hot tumour: The TONIC trial (ID 36)
- Marleen Kok (Amsterdam, NL)
New models and technologies for personalised medicine (ID 241)
50P - A novel acetylated derivative of vitexin improves the immunogenic profile of breast cancer through tuning miR-20a/MICA Axis (ID 108)
- Aya R. Awad (Cairo, EG)
Abstract
Background
The activating immune ligand, MICA, acts as a “kill me” signal through the NKG2D receptor expressed on natural killer (NK) cells that are key players in the fight against breast cancer (BC). Shedding of MICA during BC progression acts as a formidable barrier against NK cells' immune-surveillance. Recently, miR-20a was found to mediate immune escape through repressing MICA levels on BC cells. However, targeting miR-20a/MICA using natural compounds has seldomly been investigated. Vitexin, a flavone C-glycoside, showed potent anticancer properties. It was reported that acetylation of glycosides increases their cytotoxic activity, with an unknown impact on immunogenicity. Our group has successfully isolated 3'-O-acetylvitexin from Ocimum basilicum which showed potent cytotoxic effects against colon cancer cells but has never been investigated in BC. Our aim is to unravel the role of the immunogenic miR-20a/MICA axis in BC patients and its regulation by vitexin and 3'-O-acetylvitexin.
Methods
Breast tissues were collected from 26 BC patients. ER, PR and HER2 expression was quantified using immunohistochemistry. MDA-MB-231 TNBC cells and MCF-7 HR+ BC cells were treated with serial dilutions of vitexin and 3'-O-acetylvitexin. Their cytotoxic activities were assessed using MTT, colony forming and migration assays. Total RNA was extracted, reverse transcribed, then MICA and miR-20a were quantified using qRT-PCR.
Results
miR-20a is upregulated in BC patients, while MICA was downregulated in MDA-MB-231 compared to MCF7 cells. Vitexin decreased MDA-MB-231 cellular viability and migration capacity. 3'-O-acetylvitexin resulted in a more pronounced dose-dependent repression of TNBC cellular viability, colonogenicity and migration capacity. Treatment with vitexin didn’t show any alteration in miR-20a but showed only 2 folds increase in MICA. However, 3'-O-acetylvitexin markedly decreased miR-20a with a concomitant increase in MICA by 12 folds.
Conclusions
3'-O-acetylvitexin displays more pronounced anticancer properties against TNBC through halting their progression and immune suppressive nature by modulating miR-20a/MICA axis. This highlights miR-20a/MICA axis as a potential therapeutic target in BC.
Legal entity responsible for the study
German University in Cairo (GUC).
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
78P - Leukotriene B4 receptors as a therapeutic target for triple-negative breast cancer (ID 114)
- Alexey I. Kalinkin (Moscow, RU)
Abstract
Background
Lipid mediators of inflammation, leukotrienes, are involved in tumour development and progression. Leukotriene B4 receptors 1 and 2 (LTB4R and LTB4R2) have been suggested to regulate tumor progression by promoting cell proliferation, survival, migration and metastasis. LTB4R2 was reported to increase invasiveness of breast cancer (BC) cells through IL-8 (interleukin-8) pathway. The inhibitors of leukotriene receptors have been suggested for use in anti-cancer therapy.
Methods
We conducted Xma1-RRBS (Reduced Representation Bisulfite Sequencing) protocol for genome-wide DNA methylation assessment on 170 BC samples and 10 normal breast tissue samples as a reference material. Methylation status was determined by Bismark software, and identification of epigenetic BC molecular subtypes was carried out using hierarchical cluster analysis.
Results
One of the BC epigenetic subtypes identified by genome-wide DNA methylation analysis appeared to be enriched with triple-negative breast cancer (TNBC) samples demonstrating LTB4R and LTB4R2 genes abnormal demethylation that is potent of initiating ectopic gene expression. Bisulfite Sanger sequencing has confirmed abnormal demethylation of the cytosine residues at positions +117, +121, +148, +184 and +186 relative to the LTB4R transcription start site.
Conclusions
By the present day no diagnostic panels to assess the methylation status of leukotriene B4 receptors have been published. Fine mapping of abnormal DNA methylation in the genomic region adjacent to LTB4R and LTB4R2 genes reported here allows development of a simple methylation sensitive PCR laboratory test that would identify tumours prone to leukotriene B4 receptors ectopic expression and thus potentially responsive to their inhibitors. An easy means to select such tumours promotes clinical trials aimed to improve TNBC individualized therapy by introducing the inhibitors of leukotriene receptors as anticancer agents.
Legal entity responsible for the study
Research Center for Medical Genetics RAMS.
Funding
Russian Science Foundation (project No.18-15-00430).
Disclosure
All authors have declared no conflicts of interest.
Macroevolution and impact on treatment resistance (ID 245)
Single T cell sequencing in breast cancer (ID 29)
- Sherene Loi (Melbourne, AU)
13P - Expression of HER2-neu, SKP2 and HIF-1 and their role in predicting the response of muscle invasive urothelial carcinoma to bladder- preservation chemotherapy (ID 64)
- Enas A. Elkhouly (Shebin El Kom, EG)
Abstract
Background
Cystectomy is the prime treatment of muscle-invasive urothelial carcinoma but it is associated with many complications and affects patients’ quality of life. Chemotherapy is an alternative modality, but it may not give the expected response. This arouses the need for markers that help to predict the response to chemotherapy. Her2-neu, Skp2 and HIF-1 regulate cell cycle progression, tumor adaptation to hypoxic environment and response to chemotherapy. This study aimed at evaluation of HER2-neu, SKP2 and HIF1 expression in muscle-invasive urothelial carcinoma and investigating the association between their expression and tumor response to chemotherapy.
Methods
One hundred specimens of non-metastatic muscle-invasive urothelial carcinoma were collected at the Pathology Department and the selected patients received the treatment and were followed up at the Clinical Oncology Department, Menoufia University. HER2-neu, SKP2 and HIF-1expression were evaluated using immunohistochemical techniques. The patients received chemotherapy followed by cystoscopic examination. Bladder biopsy was examined to determine tumor response.
Results
A significant association was found between partial tumor response to chemotherapy and HER2-neu, SKP2 and HIF-1 positive expression (P = 0.004, 0.029 and 0.004,). Skp2 expression was significantly associated with low apoptotic count and high mitotic one (P = 0.008 and 0.01), while HIF-1 expression was significantly associated with necrosis (P = 0.008). A statistically significant association was found between Skp2 and HR2-neu expression (P = 0.018) and between SKP2 and HIF-1 expression as well (P = 0.013).
Conclusions
This study showed that HER2-neu, SKP2 and HIF-1expression can predict poor response to chemotherapy in muscle-invasive urothelial carcinoma and helps in selecting patients who will benefit from chemotherapy. In addition, targeted therapy against these markers can be effective in treatment.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
46P - Potential prognostic markers for recurrence and survival in triple-negative breast cancer (ID 125)
- Kristina V. Havrysh (Kiev, UA)
Abstract
Background
Triple-negative breast cancer (TNBC) subtype is associated with an adverse outcome among BC patients. Since Overall Survival (OS) and recurrence prediction are significant to define suitable treatment strategies, an identification of prognostic markers for Disease-Free Survival (DFS) and OS is relevant. Here we aimed to estimate the effects of previously identified predictors of DNA-damaging therapy POLR2L, RAD50, SLC34A2, SMARCA5 and WDHD1 on OS and DFS in TNBC.
Methods
Clinicopathological data of 1098 BC patients (TCGA Breast Invasive Carcinoma) and information of expression and copy number alterations (CNA) of selected genes were downloaded from the public cBioPortal site (
Results
Among studied covariates, high mRNA expression of POLR2L (HR = 1.7; 95% CI: 1.16-2.48; p-value = 0.006) and RAD50 (HR = 1.9; 95% CI: 1.02-3.64; p-value = 0.043) genes and the progressive stage of disease (HR = 4.0; 95% CI: 2.08-7.68; p-value =3.15x10-5) were associated with worse OS of TNBC patients. Also high mRNA expression of POLR2L (HR = 1.9; 95% CI: 1.16-3.00; p-value = 0.01) gene and progressive stage of disease (HR = 3.379; 95% CI: 1.601-7.132; p-value = 0.001) were associated with increased risk of cancer relapse. All possible combinations of the examined genes and characteristics were tested to select a most powerful prognostic model. For OS (Log-rank test: p-value = 3.415x10-7) and DFS (Log-rank test: p-value = 3.331x10-5) the best multivariate Cox regression model included a combination of mRNA expression of POLR2L and RAD50 genes and tumor stage.
Conclusions
Our findings display that the mRNA expression of POLR2L and RAD50 genes both separately and in combination with a stage of disease influence on OS and DFS of TNBC patients. Thus, POLR2L and RAD50 could be considered as new potential prognostic markers of TNBC.
Legal entity responsible for the study
Research Laboratory “Biomarker”, IFMB KFU.
Funding
Program of Competitive Growth of Kazan Federal University.
Disclosure
All authors have declared no conflicts of interest.
73P - Role of miR-449 family on doxorubicin-based chemotherapy response in triple-negative breast cancer (ID 220)
- EDUARDO Tormo Martin (Valencia, ES)
Abstract
Background
microRNAs (miRNAs) emerge as a new step in the modulation of breast cancer response to treatment. The family of microRNAs 449 has been described as strong inducers of cell cycle arrest (including senescence) and apoptosis in distinct tumor types. The aim of this work is to analyse the miR-449 role in doxorubicin chemotherapy-based treatment of triple-negative breast cancer (TNBC).
Methods
Experiments were made on MDA-MB-231 and MDA-MB-231R (doxorubicin resistant) triple-negative breast cancer cells. Signature of miRs-449 and their target expression was measured by real time PCR and western blot. Functional and molecular studies of loss/gain of function and response to treatment were carried out trough transient transfection of miRNAs mimics/inhibitors. Functional studies included Cell Proliferation Studies (MTT/Colony Formation Assay), Viability, Apoptosis and Cell cycle (Flow Cytometry), Invasion and Metastasis (Wound healing/Migration-Invasion Chambers).
Results
Through bioinformatic tools, we obtained the promoter sequence of the miR-449/CDC20B gene, emerging as a "hot spot", since it presented mutations, copy number variation (CVN), simple nucleotide polymorphisms (SNPs), and methylation. We also identified targets of this miRNAs family related to cancer pathways. Through in vitro studies, we obtained results of differential expression of miRs-449 between MDA-MB-231 and MDA-MB-231R treated with doxorubicin. In loss/gain of miR-449 function studies, we verified the modulation of some of their targets, and their impact on viability and on the cell cycle. Ex vivo studies have confirmed the positive correlation of the expression of the inducer factor of miRs-449, E2F1, with the sensitivity to doxorubicin treatment in triple-negative breast cancer patients. Using the KM Plotter-miRPower software, we have been able to correlate the overexpression of the CDC20B gene and the miR-449 with a higher probability of survival in breast cancer patients.
Conclusions
Results reveal for the first time the involvement of the miRNA-449 family in TNBC doxorubicin resistance, and suggest that regulation of its target genes, may be the mechanism behind their involvement.
Legal entity responsible for the study
INCLIVA Biomedical Research Institute.
Funding
CIBERONC / INCLIVA.
Disclosure
All authors have declared no conflicts of interest.
108P - The effect of the seleno-L-methionin, sodium selenite and cadmium chloride on telomerase activity of chick embryo neural tube cells (ID 163)
- Homa Akhavan (Rasht, IR)
Abstract
Background
Telomerase is a ribonucleoprotein enzyme with reverse transcriptase activity, that more important in developmental processes including cell proliferation, differentiation, senescence and tumorigenesis. Selenium as a trace element for animals and human has been detected which can have anticancer properties, while cadmium (Cd) is a heavy metal in the natural environment and is very toxic. Purpose of this study was investigating the effects of Seleno-L-methionine, Sodium selenite and Cadmium chloride on the expression of telomerase activity in Chick embryo neural tube.
Methods
Using quantitative and qualitative methods RTQ- TRAP and TRAP assay, the effect of the noted elements on the telomerase activity of Chick embryo neural tube was studied.
Results
Unlike expected, seleno-L-methionine increased telomerase activity. Cadmium chloride had the greatest effect on telomerase activity, while the effect of Sodium selenite was lower than two others. However, the increasing effect has been determined.
Conclusions
All three compounds at concentration of 5 μM and effect time of 6 hours had most impact on Chick embryo neural tube telomerase activity compared to the control groups. Cadmium chloride had greatest effect and sodium selenite were less effective.
Legal entity responsible for the study
Ardabil University of Medical Sciences.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.