Table 1.

Biological Properties of TPR-MET mutants

Tpr-Met protein*	Transformation,† %	Tumorigenicity‡	Anchorage-independent growth§	Invasion¶	Metastasis‖
Wild type	100	6/6	15  ±  3	130  ±  30	12/12
Double F	0	ND	ND	ND	ND
Grb2−	11	6/6	0	<10	0/12
2× Grb2	150	6/6	0	<10	0/12

^*Schematic representation of Tpr-Met wild type and of the Tpr-Met proteins bearing mutations in the “multifunctional” docking site. White boxes represent the Tpr moiety; gray boxes represent the Met tyrosine kinase domain. YVHV-YVNV indicates the sequence of the multifunctional docking site. The N, critical for Grb2 binding, is underlined. 

^†Ability to induce foci of transformation, expressed as relative transforming activity (percent of TPR-MET). 

^‡Number of mice developing tumors 3 weeks after subcutaneous injection of 10⁶ cells. ND, not done. 

^§Ability to form colonies in soft agar, evaluated as number of colonies (>30 cells) grown after 21 days. 

^¶Ability to invade reconstituted basement membranes “in vitro,” evaluated as number of cells per microscopic field migrated into the transwell lower chamber after 48 hr. 

^‖Number of mice dead because of lung metastasis, 3 weeks after injection of 10⁶ cells into the tail vein.