Elevated serum levels of human relaxin-2 in patients with esophageal squamous cell carcinoma

Table 1 Relationship between serum levels of human relaxin 2 and clinicopathological factors

Clinicopathological factors	Groups1		P value2
	A (n)	B (n)
Age (yr)			0.144
< 65 (n = 72)	21	51
≥ 65 (n = 69)	22	47
Tumor status			0.089
T1 (n = 16)	2	14
T2 (n = 14)	4	10
T3 (n = 75)	24	51
T4 (n = 36)	13	23
Lymph node involvement			0.003
Positive (n = 90)	32	58
Negative (n = 51)	11	40
Distant metastasis			0.027
Positive (n = 32)	21	11
Negative (n = 109)	22	87
Lymphovascular invasion			0.186
Positive (n = 42)	18	24
Negative (n = 99)	25	74
Stage (TNM)			0.035
I (n = 17)	7	10
II (n = 37)	8	29
III (n = 53)	10	43
IV (n = 34)	18	16
Cell differentiation			0.267
Well (n = 23)	9	14
Moderate (n = 90)	23	56
Poor (n = 28)	9	19

¹Patients were grouped by preoperative serum levels of human relaxin 2 (H2 RLN). In group B (n = 43), serum H2 RLN levels were ≥ 0.462 ng/mL, and in group A (n = 98), H2 RLN levels were 0.462 ng/mL;

²P values were determined by χ² test. TNM: Tumor-node-metastasis.

Table 2 Levels of serum human relaxin 2 in patients with esophageal squamous cell carcinoma

Category	H2 RLN (ng/mL)	P value
Normal control (n = 112)	0.34 ± 0.12	0.0261
ESCC (n = 141)	0.48 ± 0.17
Tumor status		0.1422
T1 (n = 16)	0.32 ± 0.08
T2 (n = 14)	0.53 ± 0.13
T3 (n = 75)	0.49 ± 0.16
T4 (n = 36)	0.47 ± 0.19
Lymph node involvement		0.0141
Positive (n = 90)	0.74 ± 0.15
Negative (n = 51)	0.45 ± 0.12
Distant metastasis		0.0161
Positive (n = 32)	0.90 ± 0.19
Negative (n = 109)	0.43 ± 0.14
Lymphovascular invasion		0.3422
Positive (n = 42)	0.51 ± 0.18
Negative (n = 99)	0.46 ± 0.16
Stage (TNM)		0.0022
I (n = 17)	0.42 ± 0.09
II (n = 37)	0.46 ± 0.12
III (n = 53)	0.47 ± 0.14
IV (n = 34)	0.82 ± 0.23
Cell differentiation		0.5421
Well (n = 23)	0.46 ± 0.21
Moderate (n = 90)	0.48 ± 0.13
Poor (n = 28)	0.52 ± 0.12

P value was determined by:

¹Student’s t test (two-tailed) or

²one way analysis of variance test. ESCC: Esophageal squamous cell carcinoma; H2 RLN: Human relaxin 2; TNM: Tumor-node-metastasis.

Table 3 Univariate and multivariate survival analysis in patients with esophageal squamous cell carcinoma

Characteristic	Univariate analysis			Multivariate analysis
	HR	95%CI	P value1	HR	95%CI	P value1
Age (yr)
< 65 vs≥ 65	1.321	0.864-1.743	0.185	1.268	0.747-1.826	0.174
Gender
Male vs female	0.942	0.621-1.563	0.342	0.852	0.732-1.472	0.296
Lymph node involvement
Yes vs no	2.136	1.142-2.687	< 0.001	2.830	1.384-2.982	0.001
Distant metastasis
Yes vs no	3.784	2.543-5.894	< 0.001	3.549	1.302-3.108	0.001
pTNM
I-II vs III-IV	3.120	2.148-5.143	< 0.001	1.632	1.130-2.740	0.028
Lymphovascular invasion
Yes vs no	1.121	0.765-1.574	0.129	1.290	0.862-1.420	0.172
H2 RLN level
< 0.462 ng/mL vs≥ 0.462 ng/mL	2.469	1.362-2.836	0.015	2.530	1.424-2.732	0.003

¹Cox hazard regression model. HR: Hazard ratio; TNM: Tumor-node-metastasis; H2 RLN: Human relaxin 2.