Table 1

Expression of amino-terminal ezrin inhibits metastasis of breast carcinoma cells

Cell line^a

Transfected with

Primary tumour takes (%)

Day of 1 cm tumour diameter^b

Day of sacrifice

Metastasis (%)^c

SP1

None

100% (13/13)

24 ± 7

35

23% (3/13)

AC2M2

None

100% (11/11)

30 ± 5

41

90% (10/11)^†

pCB6

Vector

100% (8/8)

33 ± 4

39

88% (7/8)

WTC4

WT ezrin

100% (7/7)

28 ± 4

41

88% (6/7)

WTC6

WT ezrin

100% (15/15)

26 ± 2

39

87% (13/15)

NTC6

N-term ezrin

38% (3/8)

40 ± 10*

47

0% (0/8)^‡

NTC7

N-term ezrin

100% (8/8)

28 ± 1

39

38% (3/8)^‡

NTB8^d

N-term ezrin

100% (5/5)

29 ± 3

41

0% (0/5)^‡

^aPoorly metastatic parental SP1 cells or highly metastatic variant AC2M2 cells alone, or transfected with empty pCB6 vector, or a vector encoding wild-type (WT) ezrin or amino-terminal (N-term) ezrin, were transplanted (7.5 × 10³ cells) into the mammary fat pad of syngeneic mice (see text). ^bDay to 1 cm tumour diameter was calculated by linear regression analysis of data from individual mice. Values are expressed as mean ± standard deviation. Clone NTC6 showed a significant increase (*) in the day of 1 cm tumour diameter compared with WTC4 and WTC6 (P = 0.012). Mice with NTC6 tumours were therefore killed approximately 1 week later to allow tumour growth to a comparable size. ^cAC2M2 cells showed significantly more metastases than did the parental SP1 cells (^†P = 0.003; Fisher's exact test). Pooled results from three N-term ezrin expressing clones showed a significant reduction in metastases compared with two WT ezrin expressing clones (^‡P < 0.0001). Individual P values for NTC6, NTC7 and NTB8 are as follows (respectively): <0.0001, 0.002 and 0.002. ^dNTB8 is an N-term ezrin-expressing clone derived from an independent transfection of AC2M2 cells, and was transplanted as described above.

Elliott et al. Breast Cancer Research 2005 7:R365   doi:10.1186/bcr1006