Cancer Sciences Division, School of Medicine, Cancer Research UK Centre, Southampton General Hospital, The Somers Cancer Research Building (MP824), University of Southampton, Southampton SO16 6YD, UK.
Br J Nutr. 2010 Nov;104(9):1288-96. doi: 10.1017/S0007114510002217. Epub 2010 Jun 15.
Dietary intake of isothiocyanates (ITC) has been associated with reduced cancer risk. The dietary phenethyl ITC (PEITC) has previously been shown to decrease the phosphorylation of the translation regulator 4E binding protein 1 (4E-BP1). Decreased 4E-BP1 phosphorylation has been linked to the inhibition of cancer cell survival and decreased activity of the transcription factor hypoxia-inducible factor (HIF), a key positive regulator of angiogenesis, and may therefore contribute to potential anti-cancer effects of PEITC. In the present study, we have investigated the in vitro and in vivo effects of watercress, which is a rich source of PEITC. We first demonstrated that, similar to PEITC, crude watercress extracts inhibited cancer cell growth and HIF activity in vitro. To examine the effects of dietary intake of watercress, we obtained plasma and peripheral blood mononuclear cells following the ingestion of an 80 g portion of watercress from healthy participants who had previously been treated for breast cancer. Analysis of PEITC in plasma samples from nine participants demonstrated a mean maximum plasma concentration of 297 nm following the ingestion of watercress. Flow cytometric analysis of 4E-BP1 phosphorylation in peripheral blood cells from four participants demonstrated significantly reduced 4E-BP1 phosphorylation at 6 and 8 h following the ingestion of watercress. Although further investigations with larger numbers of participants are required to confirm these findings, this pilot study suggests that flow cytometry may be a suitable approach to measure changes in 4E-BP1 phosphorylation following the ingestion of watercress, and that dietary intake of watercress may be sufficient to modulate this potential anti-cancer pathway.
异硫氰酸酯（ITC）的饮食摄入与降低癌症风险有关。先前已经表明，饮食中的苯乙基异硫氰酸酯（PEITC）可降低翻译调节因子 4E 结合蛋白 1（4E-BP1）的磷酸化。4E-BP1 磷酸化的降低与癌细胞存活的抑制以及转录因子缺氧诱导因子（HIF）活性的降低有关，HIF 是血管生成的关键正调节剂，因此可能有助于 PEITC 的潜在抗癌作用。在本研究中，我们研究了水芹的体外和体内作用，水芹是 PEITC 的丰富来源。我们首先证明，类似于 PEITC，粗水芹提取物可抑制体外癌细胞生长和 HIF 活性。为了研究水芹饮食摄入的影响，我们从先前接受过乳腺癌治疗的健康参与者中获得了摄入 80 克水芹后的血浆和外周血单核细胞。对来自九名参与者的血浆样本中的 PEITC 分析表明，摄入水芹后血浆中的最大浓度为 297nm。对四名参与者的外周血细胞中 4E-BP1 磷酸化的流式细胞术分析表明，摄入水芹后 6 和 8 小时，4E-BP1 磷酸化明显降低。尽管需要更多的参与者进行进一步研究来证实这些发现，但这项初步研究表明，流式细胞术可能是一种合适的方法来测量摄入水芹后 4E-BP1 磷酸化的变化，并且饮食摄入水芹可能足以调节这种潜在的抗癌途径。
