Integrin αvβ6 sustains and promotes tumor invasive growth in colon cancer progression

Table 1 Clinicopathological characteristics for 100 patients with colon carcinoma

Characteristic	Number of patients	Percentage
Sex
Male	54	54
Female	46	46
Age (yr)
< 60	61	61
≥ 60	39	39
Tumor location
Right	39	39
Transverse	10	10
Left colon	51	51
Depth1
< 5 mm	72	72
≥ 5 mm	28	28
Maximum diameter of tumor (cm)
≥ 1.0 and < 5.0	67	67
≥ 5.0	33	33
Tumor differentiation
Well	19	19
Moderate	53	53
Poor	21	21
Unknown	7	7
Lymph node metastasis
0	23	23
1-4	32	32
≥ 5	45	45
Venous vessel invasion
Absent	42	42
Present	58	58
Tumor margin
Expanding	81	81
Infiltrating	19	19

¹Depth of penetration beyond the muscularis propria.

Table 2 Effects of both integrin αvβ6 and matrix metalloproteinase-9 expression in100 cases of colon carcinoma

Variable		Immunoreactivity of tumor samples (n)
		Positive	Low expression		High expression
ανβ6	Deep section of tumor	38	27	71.1%	11	28.9%
	Superficial section of tumor	38	10	26.3%	28	73.7%1
MMP-9	Deep section of tumor	68	35	51.5%	33	48.5%
	Superficial section of tumor	68	16	23.5%	52	76.5%1

¹χ² test indicates that increased integrin ανβ6 expression rates are significantly different between the superficial section and deep section of the tumors (P < 0.05). There is also a significant difference for the increased MMP-9 expression rates between the superficial section and deep section of the tumors (P < 0.05). ανβ6: Integrin ανβ6; MMP-9: Matrix metalloproteinase-9.

Table 3 Five year survival estimates for 100 patients with colon cancer

Groups	Negative/positive	n	Median survival (mo) and 95%CI	5-yr survival rate (%) and 95%CI
αvβ6	Negative	62	45.948 (40.575-51.320)	0.585 (0.452-0.718)
	Positive	38	36.114 (28.501-43.728)	0.402 (0.220-0.584)1
MMP-9	Negative	32	44.071 (36.812-51.330)	0.570 (0.392-0.748)
	Positive	68	41.686 (36.040-47.331)	0.485 (0.344-0.626)2

¹Log-rank test indicates a significant survival difference between negative vs positive integrin ανβ6 expression groups (χ² = 3.919; P = 0.048; P < 0.05);

²There was no significant difference between negative vs positive MMP-9 expression groups (χ² = 0.451; P = 0.502; P > 0.05). ανβ6: Integrin ανβ6; MMP-9: Matrix metalloproteinase-9.