Fibrous sheath interacting protein 1 overexpression is associated with unfavorable prognosis in bladder cancer: a potential therapeutic target

Figures & data

Table 1 The comparison of clinicopathological characteristics between FSIP1-positive and FSIP1-negative bladder cancer patients (n=225)

Variables	N	FSIP1-negative	FSIP1-positive	P-value
Gender				0.063
Female	34	21	13
Male	191	85	106
Age (years)				0.108
<60	121	63	58
≥60	104	43	61
Tumor grade				0.682
G1/2	122	59	63
G3	103	47	56
Clinical stage				0.027
Ta–T1	91	51	40
T2–T4	134	55	79
Tumor number				0.203
Unifocal	112	48	64
Multifocal	113	58	55
Tumor size				0.765
<3 cm	125	60	65
≥3 cm	100	46	54
Lymph node metastasis				0.000
No (N0)	151	91	60
Yes (N1–N3)	74	15	59

Note: The P-value was calculated using chi-square test or Fisher’s exact test.

Abbreviation: FSIP1, fibrous sheath interacting protein 1.

Figure 1 Expression of FSIP1 in bladder cancer cell lines and human bladder tumor tissues.

Notes: (A, B) Western blotting analysis (16 paired) showed that the expression of FSIP1 in BTs was significantly higher than that in matched ANTs (P=0.009). (C) Western blotting analysis showed that FSIP1 protein expressions were significantly increased in three human bladder cancer cell lines (5637, BIU-87, and T24 in particular), compared with normal human urothelium cells SV-HUC-1. (D) Quantitative real-time PCR analysis showed an increased messenger RNA expression of FSIP1 in BTs as compared with ANTs (n=10, P=0.012).
Abbreviations: ANTs, adjacent noncancerous tissues; BTs, bladder tumor tissues; FSIP1, fibrous sheath interacting protein 1; PCR, polymerase chain reaction.

Figure 2 Immunohistochemical staining of fibrous sheath interacting protein 1 in bladder cancer tissues (×400 magnification).

Notes: (A) Negative expression (0 score); (B) weak positive expression (2 scores); (C) strong positive expression (6 scores).

Table 2 Correlation between fibrous sheath interacting protein 1 expression and the clinicopathological characteristics of bladder cancer by Spearman’s correlation analysis

Variables	Spearman’s R (P-value)
Gender	0.124 (0.064)
Age	0.107 (0.109)
Tumor grade	0.027 (0.684)
Clinical stage	0.147 (0.027)
Tumor number	0.085 (0.205)
Tumor size	0.020 (0.766)
Lymph node metastasis	0.376 (0.000)

Figure 3 Kaplan–Meier survival analysis of overall survival, disease-specific survival, progression-free survival, and metastasis-free survival between FSIP1-positive and FSIP1-negative bladder cancer patients (n=225).

Note: The log-rank test was used to calculate the P-value (all P<0.01).
Abbreviation: FSIP1, fibrous sheath interacting protein 1.

Table 3 The prognostic factors for overall and disease-free survival in bladder cancer patients by univariate Cox regression analysis (n=225)

Variables	Disease-free survival			Overall survival
	HR	95% CI	P-value	HR	95% CI	P-value
Gender (male vs female)	1.596	0.930–2.740	0.090	1.376	0.784–2.416	0.266
Age (≥60 years vs <60 years)	1.050	0.739–1.492	0.785	1.040	0.711–1.520	0.840
Tumor grade (G3 vs G1/2)	5.717	3.825–8.543	0.000	9.387	5.654–15.586	0.000
Clinical stage (T2–4 vs Ta–1)	9.064	5.322–15.437	0.000	19.374	8.470–44.314	0.000
Tumor number (multifocal vs unifocal)	2.929	2.010–4.269	0.000	2.736	1.822–4.107	0.000
Tumor size (≥3 cm vs <3 cm)	1.139	0.801–1.620	0.469	1.156	0.790–1.691	0.456
Lymph node metastasis (yes vs no)	5.759	3.980–8.332	0.000	6.086	4.074–9.093	0.000
Fibrous sheath interacting protein 1 expression (positive vs negative)	2.094	1.451–3.022	0.000	2.115	1.419–3.154	0.000

Abbreviation: HR, hazard ratio.

Table 4 The prognostic factors for overall and disease-free survival in bladder cancer patients by multivariate Cox regression analysis (n=225)

Variables	Disease-free survival			Overall survival
	HR	95% CI	P-value	HR	95% CI	P-value
Gender (male vs female)	1.273	0.730–2.221	0.395	1.152	0.642–2.067	0.636
Age (≥60 years vs <60 years)	0.866	0.596–1.260	0.506	0.873	0.585–1.303	0.506
Tumor grade (G3vs G1/2)	3.015	1.859–4.891	0.000	4.066	2.263–7.305	0.000
Clinical stage (T2–4 vs Ta–1)	3.796	2.038–7.072	0.000	7.018	2.819–17.472	0.000
Tumor number (multifocal vs unifocal)	1.644	1.063–2.542	0.025	1.378	0.871–2.179	0.170
Tumor size (≥3 cm vs <3 cm)	0.993	0.679–1.453	0.972	1.124	0.745–1.696	0.576
Lymph node metastasis (yes vs no)	1.934	1.196–3.128	0.007	1.835	1.106–3.044	0.019
Fibrous sheath interacting protein 1 expression (positive vs negative)	1.704	1.090–2.664	0.019	1.671	1.033–2.704	0.037

Abbreviation: HR, hazard ratio.