Table 2.
Characteristics of included cell culture studies.
| Author, Year | Cell Line(s) | Culture Conditions *† | Lycopene Dose(s) δ | Direct Androgen Outcomes: Primary Findings | Indirect Androgen Outcomes: Primary Findings | |
|---|---|---|---|---|---|---|
| Growth | Other | |||||
| Fu, 2014 [44] | LNCaP, PC-3 | RPMI1640, 10% FBS | 0, 5, 10, 20, 40 µM | 10 µM lycopene inhibited GSTP1 methylation (p < 0.05), increased GSTP1 gene expression (p < 0.05), and reduced DNMT3A gene expression (p < 0.01) in PC-3 but not LNCaP cells | ||
| Gong, 2016 [40] | LNCaP, C4-2, PC-3, DU145 | RPMI1640, 10% FBS | 1 µM | 1 µM lycopene inhibited growth of LNCaP (p < 0.05) but not in C4-2, PC-3, or DU145 cells | 1 µM lycopene induced BCO2 gene expression in LNCaP (p < 0.05) but not DU145 cells | |
| Gunasekera, 2007 [41] | AT3, DTE | RD (50% RPMI1640 + 50% DMEM), 2% FBS | 0.02, 0.2, 5, 10, 20 µM | 0.2 µM lycopene inhibited growth of AT3 (p < 0.0001) but not DTE cells | ||
| Ivanov, 2007 [32] | LNCaP, PC-3 | RPMI1640 or DMEM, 10% FBS | 0.01–10 µM (cell proliferation) 0.2, 0.4 µM (protein expression) 0–100 µM (androgen responsiveness) |
Lycopene did not inhibit reporter activity of ARE-Luc transfected LNCaP cells at any concentration (no statistical values reported) | 0.2–0.8 µM lycopene inhibited growth of LNCaP and PC-3 cells (p < 0.05) | 0.2–0.8 µM lycopene inhibited Akt phosphorylation, cyclins D1 and E, and CDK2 in LNCaP and PC-3 cells (no statistical values reported) |
| Linnewiel-Hermoni, 2015 [33] | LNCaP, PC-3, DU145 | RPMI1640 or DMEM, 10% FCS, 10−9 DHT (for growth, stripped of steroid hormones prior to treatment) | 1–5 µM (cell proliferation) 8 µM (ARE-Luc) 2.5 µM (PSA) |
8 µM lycopene inhibited DHT-induced reporter activity of ARE-Luc transfected LNCaP cells (p < 0.01); non-significant decrease of DHT-induced PSA secretion by LNCaP cells treated with 2.5 µM lycopene | 1–5 µM lycopene inhibited DHT-induced growth of LNCaP cells (p < 0.01) | |
| Liu, 2006 [34] | LNCaP, PC-3, DU145 | RPMI1640 or Ham’s F12K or EMEM, 10% FBS | 1–1.48 µM | 1.48 µM lycopene did not directly bind to the AR (no statistical values reported) | Uptake is highest in LNCaP (p < 0.001) with 1.48 µM lycopene compared to PC-3 or DU145 cells | |
| Liu, 2008 [35] | 6S, 6S + NPE | DMEM, 5% FBS | 0.3, 1 µM | 0.3, 1 µM lycopene increased CM-mediated cell death and reduced IGF-I gene expression of 6S + NPE cells in the presence of DHT (p < 0.01); lycopene reduced DHT-induced total (p < 0.05) and nuclear (p < 0.01) AR protein expression in 6S cells | ||
| Peternac, 2008 [36] | LNCaP, C4-2 | T medium (80% DMEM + 20% Ham’s F12K) + 10% FCS | 0.04, 0.4, 4 µg/mL (equivalent to 0.075, 0.75, and 7.5 µM) | Lycopene did not reduce PSA gene or protein expression in LNCaP or C4-2 cells at any concentration | Lycopene inhibited growth of LNCaP (0.04, 0.4, 4 µg/mL) and C4-2 (0.4, 4 µg/mL) cells (p < 0.05) | |
| Rafi, 2013 [37] | PC-3 | RPMI1640, 10% FBS | 25 µM | 25 µM lycopene led to fold reductions of kallikrein peptidase family proteins gene expression in PC-3 cells (only fold reductions reported—no other statistical values reported) | ||
| Richards, 2003 [38] | LNCaP | Did not report cell culture conditions | 1, 10 µM | 1, 10 µM lycopene appeared to reduce PSA in LNCaP cells (no statistical values reported) | ||
| Tang, 2005 [42] | LNCaP, PC-3, DU145 | DMEM + Ham’s F12K, 10% FBS | Up to 50 µM | 10–50 µM lycopene more potently inhibited growth of PC-3 and DU145 cells (p < 0.01) compared to LNCaP cells | ||
| Tang, 2011 [43] | LNCaP, LAPC-4, PC-3, 22Rv1, DU145 | RPMI1640, 10% FBS | 1 µM | 1 µM lycopene appeared to reduce growth of all cell lines (no statistical values reported) | 1 µM lycopene more potently reduced Akt phosphorylation in DU145 (by 60%) than LNCaP (by 20%) cells (no statistical values reported) | |
| Zhang, 2010 [39] | LNCaP | RPMI1640, no other conditions reported | 0.5, 5, 10, 15 µM | 0.5–15 µM lycopene appeared to reduce reporter activity and ARE protein expression in ARE-Luc transfected LNCaP cells (no statistical values reported) | ||
* All studies reported standard incubator conditions (5% CO2, 37 °C) unless otherwise stated. † Media does not contain added androgens unless otherwise stated; FBS and FCS supply castrate levels of androgens. δ Compare to reference of ~1 µM in human plasma. Abbreviations: GSTP1 (glutathione S-transferase Pi 1); DNMT3A (DNA methyltransferase 3A); BCO2 (β-carotene 9′,10′-oxygenase 2); ARE (androgen receptor element); Luc (luciferase); CDK2 (cyclin-dependent kinase 2); DHT (dihydrotestosterone); PSA (prostate-specific antigen); AR (androgen receptor); CM (camptothecin); IGF-I (insulin-like growth factor-I).