Icer Mehmet Arif, Koçak Tevfik, Acar-Tek Nilüfer, Yesil Suleyman, Icer Yusuf
Department of Nutrition and Dietetics, Faculty of Health Sciences, Amasya University, Amasya, 05100, Turkey.
Department of Nutrition and Dietetics, Faculty of Health Sciences, Gümüşhane University, Gümüşhane, 29100, Turkey.
BMC Cancer. 2025 Aug 28;25(1):1395. doi: 10.1186/s12885-025-14300-y.
It has been shown that neopterin levels in various body fluids can help predict the diagnosis of different malignancies. Although many studies have investigated the roles of serum neopterin concentrations, tryptophan metabolism, and the dietary inflammation index (DII) in various cancers, the connection between these factors and prostate cancer (PC) remains uncertain. The aim of this study was to investigate the predictive and prognostic roles of serum neopterin, and kynurenine levels, along with the kynurenine-to-tryptophan ratio (KTR) and DII in prostate cancer.
This study was conducted with 57 newly diagnosed prostate cancer patients, 55 benign prostate hyperplasia patients, and 56 healthy male individuals in the control group, all aged 40 years and older. Participants had specific anthropometric measurements taken, and three-day food records were kept. DII was calculated based on data for thirty-four available nutrients by using food records. Serum levels of neopterin, kynurenine, tryptophan, tumor necrosis factor alpha (TNF-α), and interferon-gamma (IFN-γ) were measured using an enzyme-linked immunosorbent assay (ELISA) method.
Serum neopterin (11.79 ± 6.09), kynurenine (1655.48 ± 1122.04), TNF-α (221.59 ± 232.06) and IFN-γ (137.68 ± 107.11) levels were higher in the malignant group than in both the control (2.72 ± 0.76, 352.40 ± 69.33, 223.94 ± 226.67, and 23.03 ± 7.28, respectively) and benign groups (3.17 ± 0.74, 377.94 ± 109.05, 179.61 ± 224.36, and 25.63 ± 7.50, respectively) (p < 0.05). Another result of our study is that in the malignant group, serum neopterin levels exhibited significant positive correlations with serum kynurenine (r = 0.80, p < 0.0001), IFN-γ (r = 0.86, p < 0.0001) and TNF-α levels (r = -0.27, p = 0.0453) and DII (r = 0.30, p = 0.0229), while they exhibited weak correlations with serum PSA, and other diet parameters. Additionally, kynurenine was the only parameter showing significant differences in mean values concerning surgical margins (p < 0.05).
The findings of this study support the hypothesis that serum neopterin and specific tryptophan catabolites (e.g., kynurenine), could serve as predictive and prognostic biomarkers for prostate cancer diagnosis. However, our results do not support the hypothesis that DII and certain dietary factors play a direct role in the development or diagnosis of prostate cancer.
研究表明，各种体液中的新蝶呤水平有助于预测不同恶性肿瘤的诊断。尽管许多研究已经调查了血清新蝶呤浓度、色氨酸代谢和饮食炎症指数（DII）在各种癌症中的作用，但这些因素与前列腺癌（PC）之间的联系仍不确定。本研究的目的是探讨血清新蝶呤、犬尿氨酸水平以及犬尿氨酸与色氨酸比值（KTR）和DII在前列腺癌中的预测和预后作用。
本研究纳入了57例新诊断的前列腺癌患者、55例良性前列腺增生患者和56例年龄在40岁及以上的健康男性作为对照组。对参与者进行了特定的人体测量，并记录了三天的饮食情况。根据食物记录中34种可用营养素的数据计算DII。采用酶联免疫吸附测定（ELISA）法测定血清新蝶呤、犬尿氨酸、色氨酸、肿瘤坏死因子α（TNF-α）和干扰素-γ（IFN-γ）水平。
恶性组血清新蝶呤（11.79±6.09）、犬尿氨酸（1655.48±1122.04）、TNF-α（221.59±232.06）和IFN-γ（137.68±107.11）水平高于对照组（分别为2.72±0.76、352.40±69.33、223.94±226.67和23.03±7.28）和良性组（分别为3.17±0.74、377.94±109.05、179.61±224.36和25.63±7.50）（p<0.05）。本研究的另一个结果是，在恶性组中，血清新蝶呤水平与血清犬尿氨酸（r=0.80，p<0.0001）、IFN-γ（r=0.86，p<0.0001）和TNF-α水平（r=-0.27，p=0.0453）以及DII（r=0.30，p=0.0229）呈显著正相关，而与血清前列腺特异性抗原（PSA）和其他饮食参数呈弱相关。此外，犬尿氨酸是唯一在手术切缘平均值上显示出显著差异的参数（p<0.05）。
本研究结果支持以下假设，即血清新蝶呤和特定的色氨酸分解代谢产物（如犬尿氨酸）可作为前列腺癌诊断的预测和预后生物标志物。然而，我们的结果不支持DII和某些饮食因素在前列腺癌发生或诊断中起直接作用的假设。
