(a).
| Type of study | Enrolled subjects | Number of subjects | Omega-3 PUFA daily treatments | Control group daily treatment | Length of treatments | Antineoplastic effect observed in omega-3 PUFA-treated subjects | Reference |
|---|---|---|---|---|---|---|---|
| Randomized double-blind, placebo-controlled trial | High risk for CRC (sporadic adenomatous polyps) | 10 (control group) 10 (omega-3 PUFA group) |
OS: 4.1 g EPA-EE + 3.6 g DHA-EE | OS: 7 g olive oil | 2 wk.–3 mo. | Inhibition of abnormal rectal mucosa cell proliferation | [83] |
|
| |||||||
| Double-blind crossover trial | Healthy volunteers | 12 (control group) 12 (omega-3 PUFA group)∗ |
OS: 11 g FO (providing 4.4 g omega-3 PUFA); omega-3/omega-6 ratio in the basal diet: 0.40 | 11 g corn oil |
2–4 wk. | Inhibition of rectal mucosa cell proliferation; inhibition of PGE2 release by rectal biopsies | [84] |
|
| |||||||
| Randomized double-blind, placebo-controlled trial | High risk for CRC (sporadic adenomatous polyps) | 10 (control group) 10 (omega-3 PUFA group) |
OS: 2.5 g EPA-EE + DHA-EE |
2.5 g olive oil |
1–6 mo. | Inhibition of abnormal rectal mucosa cell proliferation (in subjects with abnormal baseline proliferation pattern) | [85] |
|
| |||||||
| Double-blind crossover trial | Healthy volunteers | 12 (control group) 12 (omega-3 PUFA group)∗ |
OS: 11 g FO (providing 4.4 g omega-3 PUFA); omega-3/omega-6 ratio in the basal high-fat diet: 0.25 | 11 g corn oil |
2–4 wk. | No effect on inhibition of rectal mucosa cell proliferation | [86] |
|
| |||||||
| Randomized double-blind, placebo-controlled trial | Patients with resected CRC or severely dysplastic polyps | 10 (control group) 17 (omega-3 PUFA group) |
OS: 9 g omega-3 PUFA-EE concentrate (providing about 4.0 g EPA-EE and 2.2 g DHA-EE) | 9 g omega-6 PUFA-EE concentrate (providing about 4.5 g LA-EE) | 6 mo. | Inverse association between colon omega-3/omega-6 PUFA and cell proliferation (in subjects with abnormal baseline proliferation pattern); suppression of polyp development | [87] |
CRC: colorectal cancer; EE: ethyl ester; FAP: familial adenomatous polyposis; FFA: free fatty acid; FO: fish oil; LA: linoleic acid; OS: oral supplementation; TG: triglycerides.
∗The same subjects were treated with FO or CO in different periods.