2350P - Single-cell RNA-seq dissecting the initiating liver metastasis cells in various cancers

Background

Liver metastasis (LM) frequently occurs in patients with various cancers; yet our understanding of the underlying salient biology is preliminary. So far, no studies have found the initiating liver metastasis cells and specific liver metastatic microenvironment in various cancers. Here, we performed single-cell RNA-seq in eight patients with LM of various cancers to solve this scientific blind spot.

Methods

Single cell RNA sequencing was performed on tissues from LM of various cancers (gastric cancer(n=2); esophageal cancer(n=1); breast cancer(n=1); lung cancer(n=3); colorectal cancer(n=1)). Also, we downloaded the single-cell RNA-seq of hepatocellular carcinoma (HCC) and corresponding five types of cancer from GEO database. Seurat were applied to sort single-cell RNA-seq of LM in various cancers and corresponding five types of primary cancer into different clusters via feature dimension reduction. Furthermore, flow cytometry was used to sort those initiating liver metastasis cells, and then those cells was verified by cell metastasis function experiment and caudal vein injection of mice.

Results

The transcriptomes of 90035, 78933, 105340 single cells among LM in various cancers, HCC, and corresponding primary cancers were extracted respectively. There were 14 clusters divided into epithelial cells of liver metastasis single cells. Differential gene analyses and ratio analyses in LM and corresponding primary cancers groups showed that C10 and C12 might be the LM initiating cells clusters. And they were both enriched in the positive regulation of cell migration. SOX6⁺ CD52⁺ epithelial cells might be the LM initiating cells in various cancers, of which promoted cancer stem cells migration. Cohorts in TCGA database also showed a worse prognosis for patients with SOX6⁺ CD52⁺ markers. The sorting SOX6⁺ CD52⁺ epithelial cells will be further verified in metastasis function experiment and caudal vein injection of mice in vitro and in vivo.

Conclusions

The initiating liver metastasis cells in various cancers has been found and verified in this study, which provided a further understanding of the potential biological mechanisms of LM in various cancers and potential target for the novel drugs.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

National Science and Natural Science Foundation.

Disclosure

All authors have declared no conflicts of interest.