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Gene & Protein in Disease Natural carotenoids prevent prostate cancer

is necessary to highlight that carotenoids are susceptible concentrations inhibited the growth of LNCaP PCa cells.
to oxidation and degradation induced by heat or light, a Although lycopene, phytoene, and phytofluene are effective
phenomenon known as photooxidation. Consequently, only at high concentrations, their co-administration at low
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experimental evidence should be interpreted with caution. concentrations of approximately 0.3 μM demonstrated a
Laboratory studies conducted on mouse models and synergistic effect. 110
cell lines have revealed that β-carotene and lycopene Interestingly, lycopene displays a variable anti-
possess apoptotic effects on PCa cells, accompanied by proliferative profile depending on the source of
reduced cellular accumulation and adhesion. Specifically, consumption. Lycopene derived from tomato paste and
the administration of lycopene at concentrations exceeding tomato extract has been shown to reduce the proliferation
1.25 μM resulted in reduced PCa cell growth by inhibiting of PCa cells in the G0/G1 and G2/M phases. Conversely,
the expression of NF-κB, TP53, BAX, and BCL-2 lycopene derived from tomato sauce and ketchup leads to
transcripts. Conversely, concentrations below 0.5 μM decreased proliferation of PCa cells in the G0/G1 phase
demonstrated no effect, thus explaining the discrepancies and increased proliferation in the S and G2/M phases.
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observed in previous studies. 101,102 Immunofluorescence Overall, these results suggest the potential benefits of
staining results further demonstrated that lycopene incorporating lycopene into the diets of prostate and breast
inhibits TNFα-induced NF-κB p65 nuclear translocation cancer patients. It is important to note that these results
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in the PC3 and MDA-MB-231 cell lines, which serve are sensitive to the TME and tissue specificity. Clinton
as models for androgen-dependent PCa and hormone- et al. demonstrated that carotenoids exhibit variable
independent breast cancer, respectively. Notably, the distribution due to different transport mechanisms. For
reduction in NF-κB activity was most prominent in the instance, lycopene tends to accumulate in the prostate,
PC3 cell line compared to PCa xenografts. In addition whereas zeaxanthin is mainly distributed to adipose tissue
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to the NF-κB p65 factor, androgen-dependent PCa and the ovaries. Evidence indicates that carotenoids have
appears to be regulated by the peroxisome proliferator- a propensity to accumulate in tissues with low-density
activated receptor gamma (PPARγ) and liver X receptor lipoprotein (LDL) receptors, such as adrenals, testes, and
alpha (LXRα). Lycopene administration (2.5 – 10 μM) has liver. However, intracellular metabolic pathways also
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been demonstrated to upregulate these receptors, thereby play a key role in the accumulation of carotenoids. Further
inhibiting the proliferation of PCa cells. Furthermore, pre-clinical and clinical studies are necessary to fully
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incubation studies demonstrated that 1.15 μmol/l of interpret the profile and effects of carotenoids on Pca, both
lycopene reduced PCa cell mobility by 40% and inhibited in vitro and in vivo.
cell adhesion in concentrations exceeding 1.15 μmol/l. 105
The majority of intervention studies investigate the 3. Potential use of carotenoids in patients
synergistic chemopreventive effects of carotenoids, as diagnosed with PCa
administering a single compound has proven to be Several trials have demonstrated the beneficial effects of
unsuccessful. In fact, studies by The Alpha-Tocopherol lycopene supplementation in patients diagnosed with
Beta Carotene Cancer Prevention Study Group and PCa. Randomized phase II clinical trials have indicated a
Omenn et al. demonstrated that supplemental β-carotene reduced PCa incidence following nutritional intervention
had a negative effect on smokers with lung cancer and with 15 mg of lycopene administered twice a day to PCa
colorectal adenoma. 106,107 However, when administered in patients before radical prostatectomy for a duration of
combination with polyphenols, vitamin E, and vitamin 3 weeks. Prostate-specific antigen (PSA) levels, clinical
A, β-carotene exhibited synergistic effects by reducing risk assessments, and follow-up increased by 14% in the
oxidative stress and the formation of lipid hydroperoxides control group, whereas they declined by 18% in the group
and malondialdehyde. Vitamin A enhances the that received lycopene. In addition to reductions in PSA
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antioxidant activity of β-carotene by eliminating oxygen levels and clinical risk assessments, the intervention group
radicals. Due to their lipophilic nature, carotenoids play a also exhibited a lower prevalence of tumors with a volume
key role in protecting cellular membranes by eliminating of <4 mL compared to the control group. Specifically,
peroxyl radicals generated during lipid peroxidation. tumors of this size were present in 84% of the intervention
Another study focusing on patients with benign breast group and 45% of the control group. In another trial,
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disease followed by premenstrual mastalgia demonstrated 54 patients with histologically proven metastatic PCa
positive results with no side effects from high-dosage were enrolled. The two treatment groups respectively
supplementation of β-carotene and retinol. Similarly, treated with orchidectomy alone and orchidectomy plus
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a combination of lycopene with phytoene, phytofluene, lycopene, each involving 27 patients. On the day of surgery,
1,25-dihydroxyvitamin D3, and retinoic acid at low administration of 2 mg of lycopene started twice a day. PSA

Volume 3 Issue 1 (2024) 9 https://doi.org/10.36922/gpd.2827