Abstract 381P
Background
The most frequent and aggressive primary brain malignancy in adults is a glioblastoma multiforme (GBM) which is frequently resistant to apoptosis-inducing chemotherapeutic agents. Surface exposure of phosphatidylserine (PS) is a universally recognized apoptotic phenomenon. Although in acute myeloid leukemia and T-cell lymphoma cells Xkr8 mediates PS exposure in response to apoptotic stimuli, the mechanisms underlying the regulation of Xkr8 expression remain unclear. Nevertheless, the loss of Xkr8 in blood cancer cells blocks cell-surface exposure of PS and causes dramatic decreasing of engulfment by phagocytes. Whether Xkr8 is dysregulated in specific cancers and contribute to the survival of patients has not been investigated. This study was aimed to investigate the association of overall survival (OS) and disease-free survival (DFS) with expression and copy number alterations (CNA) of XKR8 gene in GBM patients.
Methods
Data of gene expression, CNA and clinical information from 619 GBM tumors were obtained from TCGA Glioblastoma Multiforme study using the open platform CBioPortal. Among all cases, 572 GBM samples were with CNA (GISTIC 2.0. Values) data and 162 samples were with mRNA expression data (RNA Seq V2 RSEM). Patients were divided into two groups taking into account CNA or expression of mRNA. XKR8 expression was scored as downregulated when mRNA value was lower than the mean expression + standard deviation. XKR8 gene was marked as amplified when CNA value was equal 1 or 2. Kaplan-Meier and log-rank analyses were performed using RStudio.
Results
Survival analysis in GBM patients showed that the OS (p-value=0,015) of the group with downregulated XKR8 mRNA expression (n = 22) was better than of group with normal and upregulated expression (n = 140). Equivalent results have been shown for DFS, where the patients with low XKR8 expression (n = 15) had a weaker risk of disease recurrence (p-value=0,003) than other GBM patients (n = 103). Also, the OS of GBM patients with amplified XKR8 gene (n = 83) was worse (p-value=0,049) than of patients with other CNAs (n = 489).
Conclusions
Thus XKR8 gene can be characterized as prognostic biomarker of survival and disease progression in GBM patients.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Research Laboratory "Biomarker" IFMB KFU.
Funding
Russian Government Program of Competitive Growth of Kazan Federal University.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
117P - Short-term and long-term outcomes of hepatectomy combined with intraoperative radiofrequency ablation for multiple colorectal liver metastases: A propensity score matching study
Presenter: Wenbai Huang
Session: Poster display session
Resources:
Abstract
119P - The impacts of dose-time-fractionation schedules on pathological complete response rate (pCR) and local recurrence (LR)
Presenter: Fu Jin
Session: Poster display session
Resources:
Abstract
120P - Platelet to lymphocyte ratio is associated with tumour localization and outcomes in patients with metastatic colorectal cancer
Presenter: Ahmet Bilici
Session: Poster display session
Resources:
Abstract
121P - Meta-analysis of three-dimensional versus two-dimensional laparoscopic surgery for rectal cancer
Presenter: Laiyuan Li
Session: Poster display session
Resources:
Abstract
127P - Outcomes based on albumin‐bilirubin (ALBI) grade in the phase III CELESTIAL trial of cabozantinib versus placebo in patients with advanced hepatocellular carcinoma (HCC)
Presenter: Stephen Chan
Session: Poster display session
Resources:
Abstract
128P - Tislelizumab in combination with chemotherapy for Chinese patients (Pts) with gastric/gastroesophageal junction cancer (GC/GEJC) or esophageal squamous cell carcinoma (ESCC)
Presenter: Yuxian Bai
Session: Poster display session
Resources:
Abstract
129P - Monitoring patient-specific mutation in ctDNA and CTC for tumour response evaluation after neoadjuvant chemotherapy in advanced gastric adenocarcinoma (NCT03425058)
Presenter: Tao Fu
Session: Poster display session
Resources:
Abstract
130P - Development of a liver cancer risk prediction model for the general population in china: A potential tool for screening
Presenter: Xiaoshuang Feng
Session: Poster display session
Resources:
Abstract
131P - Cabozantinib in Asian patients with hepatocellular carcinoma and other solid tumours: Population pharmacokinetics analysis
Presenter: Chih-Hung Hsu
Session: Poster display session
Resources:
Abstract
132P - Liposomal irinotecan (nal-IRI) plus 5-fluorouracil/levoleucovorin (5 FU/LV) vs 5-FU/LV in Japanese patients (pts) with gemcitabine-refractory metastatic pancreatic cancer (mPAC)
Presenter: Tatsuya Ioka
Session: Poster display session
Resources:
Abstract