Folate in colorectal cancer: beneficial or detrimental?

Yıl 2025, Cilt: 4 Sayı: 2, 263 - 277, 31.12.2025

Altınay Altınkaynak , Hülya Kamarlı Altun

https://doi.org/10.58625/jfng-3078

Öz

Folate is a water-soluble B-group vitamin found in various foods including green leafy vegetables, hens’ eggs, and legumes. Folate has an essential role in DNA repair, methylation, and synthesis. Folate deficiency causes neural tube defects, megaloblastic anemia, cardiovascular diseases, and cancer. Foods are enriched with folic acid, a synthetic monoglutamate form of folate, and folic acid supplementation is provided in many countries because the increased need for folate during pregnancy cannot be met only with food. Due to the important roles of folate in DNA synthesis, there are concerns that exposure to high doses of folic acid may cause colorectal cancer. Studies support that folic acid taken before polyp development has protective effects from colorectal cancer. On the other hand, folic acid supplementation induces colorectal cancer after polyp formation. It is also thought that epigenetic modifications affecting folate metabolism play a role in this process. In conclusion, folate intake at optimal levels and appropriate timing may exert protective effects against colorectal cancer, whereas folic acid consumed in supraphysiological doses and at later stages may promote tumor progression and increase the likelihood of carcinogenic progression of premalignant lesions.

Anahtar Kelimeler

Folate , folic acid , colorectal cancer , colonic neoplasms

Kolorektal kanserde folat: yararlı mı, zararlı mı?

Öz

Folat yeşil yapraklı sebzeler, yumurta ve baklagiller gibi birçok besinde bulunan suda çözünen bir B grubu vitamini olarak kabul edilmektedir. DNA onarımı, metilasyonu ve sentezi gibi önemli rolleri bulunur. Eksikliğinde nöral tüp defekti, megaloblastik anemi, kardiyovasküler hastalıklar ve kanser gibi hastalıklar görülmektedir. Özellikle gebelik döneminde ihtiyacın artması ve bunun besinlerle sağlanamamasından ötürü birçok ülkede besinler folatın sentetik monoglutamat formu olan folik asitle zenginleştirilmektedir ve folik asit takviyesi sağlanmaktadır. DNA sentezindeki önemli rollerinden dolayı yüksek doz folik asite maruziyetin kolorektal kansere neden olabileceğine dair endişeler de mevcuttur. Yapılan araştırmalar polip oluşumundan önce alınan folik asidin kolorektal kanserden koruyucu etkileri olduğunu desteklemekte ancak polip oluşumundan sonra kolorektal kanser gelişimini indüklediğini ortaya koymaktadır. Ayrıca folat metabolizmasını etkileyen epigenetik modifikasyonların da bu süreçte etkili olduğu düşünülmektedir. Sonuç olarak, optimal düzeylerde ve doğru zamanda alınan folat, kolorektal kanser riskini azaltıcı etkilere sahipken; fizyolojik sınırların üzerinde ve geç dönemde alınan folik asit, tümör progresyonunu destekleyebilir ve premalign lezyonların kansere dönüşme riskini artırabilir.

Anahtar Kelimeler

Folat , folik asit , kolorektal kanser , kolon neoplazmları

Kaynakça

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