Abstract 173P
Background
Cancer stem cells are thought to play important roles in carcinogenesis, recurrence, metastasis, and therapy-resistance. We have successfully induced cancer stem-like sphere cells (CSLCs) from hepatoma cell lines using a unique medium.
Methods
The human hepatoma cell line SK-HEP-1 was used as parental cells for CSLC induction. To assess the chemoresistance and liver metastasis, MTS assay and splenic injection were performed, respectively. RNA-seq analysis followed by gene set enrichment analysis (GSEA) was performed with cell line derivatives and clinical specimens of hepatoma. Protein expressions were conducted by western blotting, flow-cytometry, or ELISA. Knock-out experiments was accomplished by CRISPR-Cas9 genome-editing. Following rescue experiments were performed with an expression vector.
Results
The obtained CSLCs showed increased metastatic potentials and resistance to anti-cancer drugs including molecularly targeted drugs for liver cancer. Regarding immune resistance, CSLCs showed increased proportion of positive cells for PD-L1 and PD-L2. In contrast to decreased membrane-bound MICA/MICB, increased soluble MICA in the medium were observed in CSLCs compared to those from the parental cells. As a result of integrated analysis with RNA-seq, a RAB3B was identified as an up-regulated gene in both CSLCs and poor prognostic liver cancers. Mono-allelic RAB3B knock-out cells showed altered sphere formation, significantly lower chemoresistance, and metastatic potential than that of parental cells, and those were rescued by the complementation of RAB3B. The knock-out cells also showed decreased PD-L1 and PD-L2 expressions in sphere induction medium than those in cells cultured with normal medium. GSEA following RNA-seq with the derivative cells revealed that negative enrichment of G2M checkpoint and positive enrichment of interferon response in CSLCs.
Conclusions
Our induced CSLCs showed characteristic phenotypes such as metastatic ability, chemo- and immune-resistances. The up-regulation of RAB3B may plays important roles in CSLCs.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Ryouichi TSUNEDOMI.
Funding
Japan Society for the Promotion of Science.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
64P - Entrectinib in locally advanced/metastatic ROS1 and NTRK fusion-positive non-small cell lung cancer (NSCLC): Updated integrated analysis of STARTRK-2, STARTRK-1 and ALKA-372-001
Presenter: Filippo de Braud
Session: Poster display session
Resources:
Abstract
65P - Updated efficacy and safety of entrectinib in patients with NTRK fusion-positive tumours: Integrated analysis of STARTRK-2, STARTRK-1 and ALKA-372-001
Presenter: Christian Rolfo
Session: Poster display session
Resources:
Abstract
66P - Brain metastases, treatment patterns and outcomes in ROS1-positive NSCLC patients from US oncology community centers
Presenter: Matthew Krebs
Session: Poster display session
Resources:
Abstract
67P - Pooled safety analysis of tepotinib in Asian patients with advanced solid tumours
Presenter: Kentaro Yamazaki
Session: Poster display session
Resources:
Abstract
68P - A novel anti-EGFR antibody HLX07 for potential treatment of squamous cell carcinoma of the head and neck
Presenter: Ming Mo Hou
Session: Poster display session
Resources:
Abstract
69P - Irinotecan and cisplatin therapy-induced neutropenia as a prognostic factor in patients with extensive-disease small cell lung cancer
Presenter: Hiroshi Ishikawa
Session: Poster display session
Resources:
Abstract
70P - Is safe and efficient by intraoperative endoscopic nasobiliary drainage over primary closure of the common bile duct for cholecystolithiasis combined with common bile duct stones: A meta-analysis
Presenter: Jiasheng Cao
Session: Poster display session
Resources:
Abstract
71P - Irreversible electroporation versus radiotherapy after induction chemotherapy on survival in patients with locally advanced pancreatic cancer: A propensity score analysis
Presenter: Chaobin He
Session: Poster display session
Resources:
Abstract
72P - Novel technique of near-focus mode for accurate operation during endoscopic submucosal tunneling procedure: A two-center comparative study
Presenter: Wei Peng
Session: Poster display session
Resources:
Abstract
73P - Cabozantinib in combination with anti-PD1 immune checkpoint inhibitor in syngeneic tumour mouse models
Presenter: Rachel Sparks
Session: Poster display session
Resources:
Abstract