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Table 1. Relationship between SPC18 expression and clinicopathological characteristics of
ESCC patients
SPC18 expression
Positive
Negative
P valuea
< 65 years
19(21%)
19
1.000
≥ 65 years
27(29%)
27
Male
42(46%)
37
Female
4(4%)
T1a
3(3%)
11
T1b/2/3/4
43(47%)
35
N0
16(17%)
25
N1/2/3
30(33%)
21
11(12%)
21
II/III/VI
35(38%)
25
Negative
15(16%)
17
Positive
31(34%)
29
Negative
29(32%)
34
Positive
17(18%)
12
Well, moderately
36(39%)
32
poorly
10(11%)
14
Negative
33(36%)
40
Positiive
13(14%)
Age
Sex
0.135
T classification
0.020
N classification
0.059
Stage
0.028
Lymphatic invasion
0.662
Vascular invasion
0.262
Histological classification
0.342
EGFR expression
Chi-squared test
0.068
Yamamoto Y et al. 17
Table 2. Univariate and multivariate Cox regression analyses of SPC18 expression and
survival of ESCC patients
Characteristic
Univariate analysis
Multivariate analysis
HR (95% CI)
P value
≤ 65 years
1 (Ref.)
0.365
> 65 years
0.65 (0.25-1.67)
HR (95% CI)
P value
1 (Ref.)
0.331
Age
Sex
Female
1 (Ref.)
Male
3.51 (0.72-63.3)
0.138
T classification
T1
1 (Ref.)
T2/3/4
7.44 (2.41-32.54)
0.002
2.07 (0.50-11.42)
N classification
N0
1 (Ref.)
N1/2/3
19.88 (4.05-99.21)
0.001
1 (Ref.)
0.015
9.35 (1.45-190.84)
Lymphatic invasion
Negative
1 (Ref.)
0.009
1 (Ref.)
Positive
5.04 (1.43-32.02)
1.41 (0.25-11.23)
Negative
1 (Ref.)
1 (Ref.)
Positive
4.37 (1.69-12.27)
0.706
Vascular invasion
0.002
Histological classification
Well, moderately
1 (Ref.)
poorly
0.83 (0.28-2.23)
0.733
1.39 (0.42-5.34)
0.592
Yamamoto Y et al. 18
EGFR expression
Negative
Positive
1 (Ref.)
3.01 (1.11-7.67)
1 (Ref.)
0.031
2.65 (0.91-7.36)
0.072
SPC18 expression
Negative
1 (Ref.)
Positive
3.85 (1.43-12.13)
HR: hazard ratio; CI: confidence interval
1 (Ref.)
0.006
3.17 (1.14-10.46)
0.027
Yamamoto Y et al. 19
Figure Legends
Fig. 1. Expression of SPC18 in ESCC. a Immunostaining of SPC18 in ESCC. Original
magnification, ×10. b Immunostaining of SPC18 in ESCC. Original magnification, ×400. c
Immunostaining of EGFR in the same ESCC case shown in panel b. Original magnification,
×400. d Kaplan-Meier plot of ESCC patient survival according to SPC18 expression.
Fig. 2. Effect of SPC18 inhibition on ESCC cell lines. a Western blot analysis of SPC18 in
esophageal cancer cell lines. b Western blot analysis of SPC18 in TE-1 cells transfected with
negative control siRNA or SPC18 siRNAs. c Western blot analysis of SPC18 in TE-5 cells
transfected with negative control siRNA or SPC18 siRNAs. d Effect of SPC18 knockdown on
TE-1 cell proliferation. Cell proliferation was assessed by MTT assays at days 1, 2, and 4
after seeding in 96-well plates. e Effect of SPC18 knockdown on TE-5 cell proliferation. Cell
proliferation was assessed by MTT assays at days 1, 2, and 4 after seeding in 96-well plates.
Fig. 3. Western blot analysis of SPC18, Akt, phosphorylated Akt (pAkt), Erk1/2, and
phosphorylated Erk1/2 (pErk1/2) in lysates of TE-5 cells transfected with the negative control
siRNA or SPC18 siRNAs.
Yamamoto Y et al. 20
Yamamoto Y et al. 21
Yamamoto Y et al. 22
Fig. 3
SPC18
Akt
pAkt
Erk1/2
pErk1/2
β-actin
siRNA-3
siRNA-1
Negative
control
TE-5
...