Lycopene has limited effect on cell proliferation in only two of seven human cell lines (both cancerous and noncancerous) in an in vitro system with doses across the physiological range

Abstract

Epidemiological studies have shown a relationship between diets rich in tomato and/or lycopene and a reduction in cancer rates. Several studies reported reductions in proliferation of certain cell lines when treated with lycopene. This study used seven human cell lines to measure the effect of lycopene on cell proliferation across normal human plasma concentrations of lycopene. Seven cell types, cancerous and noncancerous, were treated with lycopene from 0.0001 to 10 μM for 24, 48, and 72 hours and counted electronically. Controls and experimental samples were compared using the MannWhitney U-test at a 95% confidence level. All cells grew normally and there was no significant difference between any of the controls. The Hep-G2, liver adenocarcinoma cell line, showed a reduction at the high doses after 24 hours and the IMR-90, noncancerous lung cell line, showed a reduction at the highest dose after 72 hours when compared to the solvent control. The A431, skin carcinoma, DU-145, prostate carcinoma, HS-68, noncancerous skin, A549, lung carcinoma, and HS-578T, breast carcinoma, all showed no reduction in proliferation. This indicated that lycopene at the physiological range does not significantly affect cell proliferation in an in vitro model and requires more careful investigations.

Carotenoids and breast cancer risk: a meta-analysis and meta-regression

“…However, the lutein uptake can be significantly impaired by a mixture of carotenoids (lycopene plus b-carotene) [53]. In vitro model, lycopene has limited effect on cell proliferation [54,55]. The effects of lycopene on mammary tumorigenesis in mice's models were also ambiguous [56][57][58].…”

Dietary Manipulation for Therapeutic Effect in Prostate Cancer

“…At physiological concentrations, however, lycopene may not have growth inhibitory effects on a variety of cell lines (Burgess et al, 2008). This was confirmed recently in experiments where supraphysiological concentrations were required to reduce growth, possibly through alterations in the cell cycle (Ford et al, 2011).…”

Investigation of the Potential Anticancer Effects of Lycopene in Tissue Engineered In vitro and In vivo Models

“…Contradictory to the studies discussed above, Burgess et al [65] reported a failure of lycopene in inhibiting growth of DU145 cells at concentrations between 0.0001 and 10 µM and over a time of 72 h. The lycopene concentrations used in this study have been reported to lie within the physiological range [65]. Liu et al [66] investigated the potential of lycopene and apo-10-lycopenal in preventing prostate cancer growth through epigenetic modifications.…”

“…After reading alamarBlue Ò fluorescent signals, hydrogels were transferred into PBS until the alamarBlue Ò reagent diffused out of the hydrogels to perform PicoGreen Ò proliferation assays. Colorless hydrogels were frozen at ¡80 C for at least 48 h. Following proteinase K treatment (0.5 mg/ml) overnight at 65 C, PicoGreen Ò fluorescent signals (excitation 480 nm and emission 520 nm) were measured using a fluorescence plate reader. The DNA content was calculated using the DNA standard curve for every timepoint and normalized to controls.…”

“…In 2008, prostate cancer was the sixth leading cause of death from cancer among men worldwide. Prostate specific antigen (PSA) testing has been shown to have a greater influence on incidence than on mortality [65]. Therefore, there is a larger variety in incidence rates than in mortality rates.…”