癌症的轉移是主要造成癌症病人死亡的主要原因，其中包括細胞的貼附、細胞外基質的降解及細胞的移動力。花青素是廣泛存在於各類的蔬果當中的色素，已有許多報告證明其具抗氧化活性，降低血脂肪，促使癌瘤細胞凋亡及防止正常細胞癌化等作用。而多類莓果及花朵中也含有豐富的花青素，其萃取物已被應用於治療許多疾病。在本篇實驗當中，我們證實了洛神花及桑椹花青素無論是在濃度或時間效應上，都可顯著的抑制具有高度轉移能力的肺癌細胞(A549)其細胞的侵犯，移動力及貼附能力。我們再利用gelatin-及casein-zymography的方法分析細胞的細胞外基質降解相關基因如MMP-2及u-PA的活性表現，結果發現花青素對MMP-2及u-PA的分泌量亦有明顯的抑制，並且都呈現濃度及時間的效應關係。從以上的結果，我們發現洛神花花青素及桑椹花青素可能是透過抑制A549細胞株MMP-2及u-PA分泌的作用進而抑制癌瘤細胞遷移和侵犯作用的能力。
Metastasis, the major cause of cancer death, is a multi-step process involving cell adhesion and proteolytic degradation of the ECM (extracellular matrix), essential to achieving cell motility. Many bioactive properties of anthocyanins, present in various fruits and vegetables as natural colorants, have been well characterized. They are widely used for their antioxidant properties. Recent studies have also revealed pleiotropic anticancer and antiproliferative capabilities of anthocyanins. Berry extract contains high amounts of anthocyanins and is commonly used in certain diet and therapeutic applications. This study demonstrates that, in the absence of cytotoxicity, anthocyanins from both roselle (HAs, extracted from Hibiscus sabdariffa L., a local Soft drink material and medical herb possessing antioxidant activity) and mulberry (MACs, extracted from Morus alba L.) exerted a dose- and time-dependent inhibitory effect on the invasion, motility, and adhesion of highly metastatic A549 human lung carcinoma cells. We examined the effect of HAs and MACs on factors of cancer metastasis. We treated A549 cells with various concentrations of HAs and MACs (up to 1 mg/mL), for set periods, then subjected cells to gelatin zymography and casein zymography to investigate the expression of matrix metalloproteinase-2 (MMP-2) and urokinase-type plasminogen activator (u-PA). Treatment by both anthocyanin preparations was found to decrease the expression of MMP-2 and u-PA in a concentration- and time-dependent manner. Both preparations also limited cell motility and cell-matrix adhesion. Together, these results suggest that anthocyanins may act to decrease the in vitro invasiveness of cancer cells and therefore, reduce the invasion and metastasis of tumor cells. This study suggests a possible role for anthocyanins in cancer therapy.
