白花前胡素B抑制人類子宮頸癌細胞轉移之分子機制

背景：白花胡前素(praeruptorins)是胡前根主要成分之一，具有抗炎和抗腫瘤促進作用。然而，白花前胡素-B（Pra-B）對子宮頸癌細胞抗轉移作用的分子機制尚不清楚。方法：使用MTT測定法檢查細胞活力，而使用Boyden chamber測定子宮頸癌細胞移動和侵襲。西方墨點法(Western blotting)和RT-PCR檢測白花前胡素-B對HeLa中誘導的基質金屬蛋白酶-2/-9 （MMP-2/-9）表達的抑制細胞。Luciferase方式分析白花前胡素-B對12-O-十四烷基佛波醇-13-乙酸酯（TPA）誘導HeLa細胞內MMP-2/MMP-9轉錄活性。實驗結果：本研究發現白花前胡素-B抑制TPA誘導的人宮頸癌細胞移動和轉移能力，且無細胞毒性。白花前胡素-B在HeLa細胞中抑制TPA誘導的mRNA和蛋白表達以及MMP-2/MMP-9的轉錄活性。我們也發現白花前胡素-B抑制TPA誘導AKT磷酸化，但不影響ERK和JNK途徑。為了證實AKT途徑是否參與白花前胡素-B抑制細胞轉移作用，我們利用TPA加白花前胡素-B或LY294002（PI3K抑制劑）共同處理會減少細胞侵襲和MMP-2 / MMP-9蛋白表達和轉錄活性。此外，白花前胡素-B減弱了TPA誘導的NF-κB-p65/-p50的核轉位，同時降低細胞內Ikk-α磷酸化。另外， TPA與白花前胡素-B或LY294002共處理HeLa細胞減少NF-κB核轉位到細胞核內。這些結果顯示白花前胡素-B抑制TPA誘導細胞轉移、抑制MMP-2/MMP-9表達及抑制p-AKT/NF-κB的表現。白花前胡素-B可能是一種抗子宮頸癌的潛在抗轉移劑。

Praeruptorins, a seselin-type coumarin, possess anti-inflammatory and anti-tumor promoting properties. However, molecular mechanisms through which Praeruptorin-B (Pra-B) exerts an antimetastatic effect on cervical cancer cells remain unclear. Cell viability was examined using the MTT assay, whereas cell migration and invasion were examined using the Boyden chamber assay. Western blotting and RT-PCR were performed to investigate the inhibitory effect of Pra-B on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced matrix metalloproteinase-2/-9 (MMP-2/-9) expression in HeLa cells. The findings of the luciferase assay confirmed the inhibitory effect of Pra-B on TPA-induced transcriptional activity of MMP-2/-9 in HeLa cells. Pra-B inhibited TPA-induced metastatic ability of human cervical cancer cells without any significant toxicity. Pra-B suppressed TPA-induced mRNA and protein expression and transcriptional activity of MMP-2/-9 in HeLa cells. Furthermore, Pra-B inhibited AKT phosphorylation but did not affect the MAPK pathway. Cotreatment of HeLa cells with TPA plus Pra-B or LY294002 (a PI3K inhibitor) reduced cell invasion and MMP-2/-9 expression and transcriptional activity. In addition, Pra-B attenuated TPA-induced nuclear translocation of NF-κB-p65/-p50, which reduced Ikk- phosphorylation in HeLa cells. Cotreatment of HeLa cells with TPA plus Pra-B or LY294002 reduced NF-κB nuclear translocation. These results suggested that Pra-B-mediated inhibition of TPA-induced cell metastasis involved the suppression of p-AKT/NF-κB via MMP-2/-9 expression in HeLa cells. Pra-B can be a potential antimetastatic agent against cervical cancer.