Circular RNA circCOL6A3_030 is involved in the metastasis of gastric cancer by encoding polypeptide

ABSTRACT

Gastric cancer (GC) is a serious digestive tract disease that threatens human life worldwide, and the prognosis of gastric cancer accompanied by distant lymph node or the distant metastasis organs is worse. The purpose of this study was to investigate the role of circular RNA COL6A3_030 (circBase ID: hsa_circ_0006401; circRNADb ID: hsa_circ_28198; circBank ID: hsa_circCOL6A3_030) in GC metastasis. qRT-PCR analysis using back-splicing primers and Sanger sequencing of PCR products were performed to identify circCOL6A3_030 in GC tissues and cell lines; RNA-FISH assay was performed to validate the subcellular localization of circCOL6A3_030. Transwell and wound-healing assays were carried out to evaluate the migration ability of GC cells. Western blot was conducted to detect the polypeptide encoded by circCOL6A3_030 in cells. circCOL6A3_030 was down-regulated in GC tissues and cell lines, while circCOL6A3_030 was up-regulated in GC with distant lymph node metastasis. The migration of circCOL6A3_030 silenced GC cells was significantly inhibited in both SGC-7901 and BGC-823 cell lines. Importantly, in vivo assay, silencing circCOL6A3_030 could reduce liver metastases from gastric cancer cells. Meanwhile, further studies suggested that circCOL6A3_030 encoded a small peptide that had a function as a tumor-promoting metastasis factor and immunohistochemistry confirmed the presence of this polypeptide. To sum up, our study showed that circCOL6A3_030 promoted GC cell migration by encoding a small peptide called circCOL6A3_030_198aa. Therefore, our results highlight the potential role of circCOL6A3_030 for clinical diagnosis and treatment of GC with distant lymph node metastasis.

Graphical abstract

KEYWORDS:

• Circcol6a3_030
• metastasis
• encoding
• polypeptide
• gastric cancer

Acknowledgements

The authors thank all patients involved in this study. Dr. Wensheng Pan received research grants from Zhejiang medicine key scientific and technology project (grant number 2018258924) and Zhejiang Provincial Key R&D Program, Department of Science and Technology (grant number 2020C03030). Dr. Chenjing Zhang received research grants from Zhejiang medicine science and technology project (grant number 2019RC094).

Authors’ contributions

Xiaoge Geng, Jingya Wang, Chenjing Zhang made significant contributions to the design of the study, conducted experiments and wrote manuscripts. Wensheng Pan analyzed and interpreted the data of gastric cancer patients, and critically revised the important knowledge content. Jiyong Jing, Xiaolu Zhou guided the statistical analysis of data and the writing of the article. Chenjing Zhang, Wensheng Pan provided research funding. All authors read and approved the final manuscript.

Consent for publication

All participants agreed to publish the study.

Financial disclosure

All Authors declare that he/she has no conflict of interest. Dr. Wensheng Pan received research grants from Zhejiang medicine key scientific and technology project (grant number 2018258924) and Zhejiang Provincial Key R&D Program, Department of Science and Technology (grant number 2020C03030). Dr. Chenjing Zhang received research grants from Zhejiang medicine science and technology project (grant number 2019RC094).

Ethics approval

All procedures carried out in studies involving human participants conform to the ethical standards of the institutional Research Committee, as well as the 1964 Declaration of Helsinki and its subsequent amendments or similar ethical standards. Informed consent was given to all individuals participating in the study. This work was conducted under the approval of the Research Ethics Committee of Zhejiang Provincial People’s Hospital, Hangzhou Medical College (code: 2020QT084). The procedures for care and use of animals were approved by the Principles of Laboratory Animal Care of Zhejiang Chinese Medical University and Zhejiang Provincial People’s Hospital.  All animal studies were performed following the Guidelines for the Care and Use of Laboratory Animals of the Council of Science and Technology of China.

Disclosure statement

All researchers stated that they had no conflict of interest.

Additional information

Funding

This work was supported by the Zhejiang medicine key scientific and technology project [2018258924] and Zhejiang Provincial Key R&D Program, Department of Science and Technology [grant number 2020C03030].