The extent and importance of functional heterogeneity and crosstalk between tumor cells is poorly understood. Here, we describe the generation of clonal populations from a patient-derived ovarian clear cell carcinoma model which forms malignant ascites and solid peritoneal tumors upon intraperitoneal transplantation in mice. The clonal populations are engineered with secreted Gaussia luciferase to monitor tumor growth dynamics and tagged with a unique DNA barcode to track their fate in multiclonal mixtures during tumor progression. Only one clone, CL31, grows robustly, generating exclusively malignant ascites. However, multiclonal mixtures form large solid peritoneal metastases, populated almost entirely by CL31, suggesting that transient cooperative interclonal interactions are sufficient to promote metastasis of CL31. CL31 uniquely harbors ERBB2 amplification, and its acquired metastatic activity in clonal mixtures is dependent on transient exposure to amphiregulin, which is exclusively secreted by non-tumorigenic clones. Amphiregulin enhances CL31 mesothelial clearance, a prerequisite for metastasis. These findings demonstrate that transient, ostensibly innocuous tumor subpopulations can promote metastases via “hit-and-run” commensal interactions.
Bibliographical noteFunding Information:
We thank the Brugge lab members for helpful discussions, Grace Gao for lab management, Dr. Angie Martinez Gakidis for scientific editing and critical review of the paper, Dr. Yiling Lu and the RPPA team at MD Anderson for running the RPPA samples, Dr. Bakhos A. Tannous for the kind gift of the secreted Gaussia Luciferase construct, Dr. Laura Pontano Vaites from Dr. Wade J. Harperʼs lab for providing the amphiregulin lentiviral vector, Dr. Hyo-eun C. Bhang and Dr. Frank Stegmeier for providing the barcode constructs, Min Hu from Dr. Nicholas Navin’s lab for assisting with the CNA analysis, Dr. Myron Peto from Dr. Paul Spellman’s lab for uploading the WES data to NCBI, Anita L. Hawkins and Shumei Wang for their help with the ERBB2 FISH analysis. The time lapse movies were acquired with the support of The Nikon Imaging Center at Harvard Medical School. Whole-slide scans of tissue were acquired at the Neurobiology Imaging Facility at Harvard Medical School. The assay for Luciferase activity was performed at ICCB-Longwood Screening Facility at Harvard Medical School. Financial support: This research was supported by NCI grant CA181543 (Joan S. Brugge) and Dr. Miriam and Sheldon G. Adelson Medical Research Foundation (Joan S. Brugge and Gordon B Mills), MD Anderson CCSG grant R50 CA221675 (Gordon B. Mills), R33CA214310 and OC130649 (Tan A. Ince), The Knight Cancer Institute (Paul Spell-man), NINDS P30 Core Center Grant #NS072030 (Neurobiology Imaging Core), 5T32GM07133 (Timothy Butler) and 129098-RSG-16-092-01-TBG (Nicholas Navin).
© 2020, The Author(s).