Expression profile of polyunsaturated fatty acids in colorectal cancer

Table 1 Antibodies, working dilutions and sources

Antibody	Dilution	Source
VEGF	1:40	Santa Cruz Biotechnology, Inc.
Ki-67	1:100	Dako North America. Inc.
p53	1:160	Santa Cruz Biotechnology, Inc.

VEGF: Vascular endothelial growth factor.

Table 2 Demographic and clinical characteristics of the study subjects

Clinicopathologic parameter	n = 82
Sex
Male	51
Female	31
Age (yr)
< 60	38
≥ 60	44
Location
Colon	44
Rectum	38
Tumor size (cm)
< 5	42
≥ 5	40
Differentiation degree
High	24
Middle	53
Low	5
Clinicopathological stage
I + II	35
III + IV	47
Lymph node metastasis
Negative	40
Positive	42

Table 3 Fatty acid composition (by percentage) in colorectal carcinoma cancerous tissue and adjacent normal tissue

Fatty acid	Adjacent normal tissue	Cancerous tissue	P value
LA (%)	18.30 ± 2.83	15.46 ± 3.51	0.00
DGLA (%)	0.85 ± 0.29	1.32 ± 0.69	0.00
AA (%)	7.32 ± 2.73	7.62 ± 2.48	0.41
Total ω-6 PUFAs (%)	26.77 ± 3.37	24.64 ± 3.41	0.00
ALA (%)	0.09 ± 0.12	0.10 ± 0.13	0.32
EPA (%)	0.25 ± 0.17	0.24 ± 0.18	0.72
DPA (%)	0.43 ± 0.20	0.49 ± 0.25	0.02
DHA (%)	1.11 ± 0.50	1.33 ± 0.63	0.00
Total ω-3 PUFAs (%)	1.35 ± 0.60	1.58 ± 0.74	0.00
ω-6/ω-3PUFAs	3.88 ± 0.43	4.94 ± 0.55	0.02
AA/LA	0.42 ± 0.19	0.53 ± 0.22	0.00
AA/ω-6 PUFAs	0.27 ± 0.10	0.31 ± 0.09	0.00

LA: Linoleic acid; AA: Arachidonic acid; ALA: α-linolenic acid; EPA: Eicosapentaenoic acid; DHA: Docosahexaenoic acid; PUFAs: Polyunsaturated fatty acids; DGLA: Dihomo-gamma-linolenic acid.

Table 4 Tumor-associated factors in colorectal carcinoma cancerous tissue and adjacent normal tissue

Tumor-associated factors	Adjacent normal tissue	Cancerous tissue	P value
PGE2 (pg/mL)	221.40 ± 100.35	265.93 ± 162.22	0.12
PDGF (pg/mL)	286.09 ± 104.91	353.10 ± 148.85	0.01
VEGF (pg/mL)	211.38 ± 99.47	357.11 ± 128.76	0.00
COX-2 (ng/mL)	67.06 ± 42.22	125.21 ± 70.29	0.00

PGE-2: Prostaglandin E2; PDGF: Platelet-derived growth factor; VEGF: Vascular endothelial growth factor; COX-2: Cyclooxygenase-2.

Table 5 Relationships between fatty acid composition and tumor-associated factors in colorectal carcinoma tissue

		COX2	PGE2	PDGF	VEGF
LA	R	-0.3244	-0.1310	-0.2758	-0.1495
	P value	0.0316	0.3966	0.0700	0.3327
AA	R	0.2101	0.2663	0.1299	0.2448
	P value	0.1711	0.0806	0.4009	0.1093
AA/LA	R	0.3001	0.1855	0.1900	0.1892
	P value	0.0478	0.2280	0.2167	0.2188
ω-6 PUFAs	R	-0.2121	0.1661	-0.2373	0.0394
	P value	0.1670	0.2813	0.1209	0.7995
AA/ω-6	R	0.3083	0.2007	0.2251	0.2098
PUFAs	P value	0.0418	0.1915	0.1418	0.1717

LA: Linoleic acid; AA: Arachidonic acid; PUFAs: Polyunsaturated fatty acids; PGE-2: Prostaglandin E2; PDGF: Platelet-derived growth factor; VEGF: Vascular endothelial growth factor; COX-2: Cyclooxygenase-2.

Table 6 Relationships between polyunsaturated fatty acid tissue levels and clinicopathologic parameters in colorectal carcinoma

Clinicopathologic parameter	The number of cases	LA (%)	DGLA (%)	AA (%)	ALA (%)	EPA (%)	DPA (%)	DHA (%)	ω-3PUFA (%)	ω-6/ω-3 PUFA	AA/ω-3 PUFA	ω-6 PUFA(%)	AA/ω-6 PUFA	AA/LA
Sex
Male	51	15.3 ± 2.8	1.37 ± 0.65	0.15 ± 0.08	0.23 ± 0.13	0.24 ± 0.11	0.51 ± 0.18	1.32 ± 0.56	1.56 ± 0.65	12.2 ± 5.5	5.9 ± 2.7	24.9 ± 3.0	0.32 ± 0.10	0.55 ± 0.21
Female	31	16.1 ± 4.5	1.24 ± 0.77	0.13 ± 0.07	0.35 ± 0.18	0.25 ± 0.14	0.47 ± 0.27	1.35 ± 0.74	1.59 ± 0.48	11.6 ± 3.8	4.9 ± 1.8	24.7 ± 3.8	0.29 ± 0.10	0.49 ± 0.23
Age (yr)
< 60	38	15.8 ± 3.4	1.38 ± 0.80	0.17 ± 0.09a	0.23 ± 0.12	0.23 ± 0.11	0.50 ± 0.19	1.34 ± 0.55	1.57 ± 0.63	12.0 ± 4.0	5.6 ± 2.5	25.3 ± 2.9	0.31 ± 0.08	0.53 ± 0.20
≥ 60	44	15.4 ± 3.6	1.27 ± 0.59	0.12 ± 0.06a	0.32 ± 0.16	0.25 ± 0.16	0.48 ± 0.24	1.33 ± 0.71	1.58 ± 0.83	11.9 ± 5.7	5.5 ± 2.4	24.4 ± 3.5	0.31 ± 0.10	0.52 ± 0.23
Location
Colon	44	15.3 ± 3.3	1.30 ± 0.57	0.14 ± 0.07	0.26 ± 0.15	0.23 ± 0.14	0.50 ± 0.29	1.37 ± 0.72	1.61 ± 0.82	12.3 ± 5.9	5.6 ± 2.5	24.6 ± 3.4	0.32 ± 0.09	0.54 ± 0.22
Rectum	38	15.9 ± 3.8	1.34 ± 0.82	0.15 ± 0.06	0.30 ± 0.12	0.26 ± 0.15	0.48 ± 0.17	1.28 ± 0.53	1.56 ± 0.65	11.6 ± 3.6	5.4 ± 2.4	25.0 ± 3.1	0.30 ± 0.09	0.51 ± 0.21
Tumor size (cm)
< 5	42	15.5 ± 4.1	1.37 ± 0.78	0.15 ± 0.07	0.31 ± 0.13	0.29 ± 0.13a	0.50 ± 0.21	1.32 ± 0.49	1.61 ± 0.59	10.8 ± 2.6a	5.0 ± 2.0	24.9 ± 3.5	0.31 ± 0.10	0.54 ± 0.23
≥ 5	40	15.6 ± 2.8	1.27 ± 0.60	0.14 ± 0.06	0.24 ± 0.12	0.20 ± 0.14a	0.48 ± 0.29	1.34 ± 0.76	1.54 ± 0.88	13.2 ± 6.4a	6.0 ± 2.8	24.7 ± 3.0	0.31 ± 0.08	0.51 ± 0.20
Differentiation degree
High	24	15.6 ± 2.6a	1.18 ± 0.43	0.14 ± 0.06	0.26 ± 0.12	0.22 ± 0.12	0.46 ± 0.24	1.28 ± 0.72	1.49 ± 0.80	13.5 ± 4.9	6.6 ± 3.2a	25.0 ± 3.0	0.31 ± 0.09	0.53 ± 0.22
Middle	53	15.1 ± 3.3a	1.41 ± 0.78	0.15 ± 0.07	0.26 ± 0.14	0.26 ± 0.14	0.51 ± 0.26	1.37 ± 0.61	1.62 ± 0.73	11.4 ± 3.9	5.2 ± 1.9a	24.4 ± 3.4	0.31 ± 0.08	0.54 ± 0.20
Low	5	19.9 ± 6.3a	1.09 ± 0.60	0.15 ± 0.04	0.58 ± 0.20	0.23 ± 0.12	0.46 ± 0.14	1.24 ± 0.54	1.47 ± 0.67	11.4 ± 2.4	4.1 ± 2.0a	27.9 ± 2.4	0.25 ± 0.15	0.41 ± 0.32
Clinicopathologic stage
I + II	35	14.9 ± 3.0	1.46 ± 0.85	0.15 ± 0.09	0.21 ± 0.13	0.25 ± 0.13	0.52 ± 0.22	1.42 ± 0.55	1.67 ± 0.64	11.2 ± 3.7	5.1 ± 1.9	24.5 ± 3.1	0.32 ± 0.08	0.56 ± 0.22
III + IV	47	16.1 ± 3.8	1.22 ± 0.53	0.14 ± 0.10	0.33 ± 0.18	0.24 ± 0.14	0.47 ± 0.27	1.27 ± 0.69	1.51 ± 0.81	12.6 ± 5.6	5.8 ± 2.7	25.0 ± 3.5	0.30 ± 0.10	0.50 ± 0.22
Lymph node metastasis
Negative	40	14.9 ± 3.1	1.37 ± 0.83	0.13 ± 0.10	0.21 ± 0.13	0.24 ± 0.14	0.47 ± 0.25	1.32 ± 0.58	1.55 ± 0.66	12.5 ± 5.0	5.7 ± 2.6	24.3 ± 2.9	0.32 ± 0.08	0.56 ± 0.23
Positive	42	16.2 ± 3.8	1.27 ± 0.54	0.15 ± 0.09	0.34 ± 0.14	0.25 ± 0.13	0.51 ± 0.25	1.35 ± 0.69	1.60 ± 0.82	11.5 ± 3.6	5.4 ± 2.2	25.3 ± 3.6	0.30 ± 0.09	0.50 ± 0.21
VEGF
Positive	57	16.2 ± 3.7ab	1.32 ± 0.67	0.15 ± 0.07	0.30 ± 0.14	0.26 ± 0.13	0.48 ± 0.23	1.34 ± 0.53	1.60 ± 0.64	11.6 ± 3.7	5.0 ± 1.8b	25.2 ± 3.0	0.30 ± 0.09a	0.50 ± 0.21a
Negative	23	13.9 ± 2.7ab	1.33 ± 0.79	0.11 ± 0.05	0.23 ± 0.12	0.22 ± 0.11	0.52 ± 0.30	1.33 ± 0.65	1.54 ± 0.98	12.6 ± 7.1	6.7 ± 3.3b	23.7 ± 3.9	0.34 ± 0.09a	0.61 ± 0.21a
Ki-67
-	2	22.5 ± 10.1a	0.92 ± 0.82	0.04 ± 0.02	1.02 ± 0.55	0.25 ± 0.11ab	0.31 ± 0.02	1.25 ± 0.85	1.49 ± 1.41	10.6 ± 1.3	3.1 ± 2.5	29.9 ± 1.2	0.22 ± 0.28	0.41 ± 0.25
+	4	15.8 ± 2.7a	1.50 ± 0.31	0.19 ± 0.07	0.17 ± 0.07	0.26 ± 0.11ab	0.55 ± 0.16	1.79 ± 0.51	2.04 ± 0.63	9.9 ± 2.6	4.5 ± 1.1	26.2 ± 2.3	0.33 ± 0.04	0.56 ± 0.12
++	6	16.3 ± 4.5a	1.93 ± 1.51	0.20 ± 0.11	0.30 ± 0.07	0.36 ± 0.17ab	0.55 ± 0.23	1.26 ± 0.89	1.62 ± 0.97	12.4 ± 6.2	5.3 ± 2.3	25.5 ± 2.2	0.28 ± 0.08	0.49 ± 0.28
+++	23	15.9 ± 3.1a	1.34 ± 0.56	0.12 ± 0.06	0.28 ± 0.08	0.29 ± 0.13ab	0.50 ± 0.31	1.33 ± 0.68	1.62 ± 0.78	11.7 ± 3.4	5.5 ± 2.5	25.3 ± 2.7	0.31 ± 0.09	0.54 ± 0.23
++++	46	15.0 ± 3.1a	1.23 ± 0.60	0.15 ± 0.07	0.25 ± 0.16	0.21 ± 0.12ab	0.48 ± 0.23	1.32 ± 0.58	1.53 ± 0.70	12.1 ± 5.6	5.7 ± 2.5	24.1 ± 3.6	0.31 ± 0.08	0.53 ± 0.20
p53
+	32	15.6 ± 3.7	1.40 ± 0.84	0.15 ± 0.09	0.25 ± 0.13	0.22 ± 0.13	0.55 ± 0.22	1.46 ± 0.68	1.68 ± 0.79	11.9 ± 6.5	5.5 ± 2.7	25.2 ± 2.8	0.32 ± 0.09	0.55 ± 0.22
++	7	15.2 ± 4.2	1.70 ± 0.86	0.18 ± 0.11	0.23 ± 0.12	0.24 ± 0.09	0.58 ± 0.27	1.32 ± 0.32	1.56 ± 0.41	10.8 ± 2.4	4.9 ± 1.3	24.6 ± 3.0	0.31 ± 0.09	0.55 ± 0.25
+++	28	15.2 ± 3.3	1.27 ± 0.55	0.17 ± 0.11	0.28 ± 0.14	0.26 ± 0.11	0.50 ± 0.24	1.32 ± 0.67	1.58 ± 0.82	11.6 ± 3.9	5.4 ± 2.3	24.2 ± 4.3	0.30 ± 0.07	0.50 ± 0.19

^aP < 0.05,

^bP < 0.01 between groups. LA: Linoleic acid; AA: Arachidonic acid; ALA: α-linolenic acid; EPA: Eicosapentaenoic acid; DHA: Docosahexaenoic acid; PUFAs: Polyunsaturated fatty acids; VEGF: Vascular endothelial growth factor.