探討Lunasin及Aspirin的處理對脂肪細胞與乳癌細胞發炎與生長之影響

Abstract

乳癌為女性最常見的惡性腫瘤之一，肥胖者乳房脂肪組織中會有免疫細胞的浸潤伴隨著發炎性細胞激素的分泌，營造了適合腫瘤生長的微環境。Lunasin為43個胺基酸所組成的天然種子胜肽，已在細胞和動物實驗顯示具有效的癌症化學預防作用。Aspirin為使用已久的非固醇類抗發炎藥物，也被證實具有癌症預防作用，然而aspirin具有腸胃道副作用，因此近來許多研究使用aspirin合併其他具有癌症預防潛力的物質，期望降低其副作用並協同達到更好的抗癌效果。Lunasin及aspirin對於腫瘤微環境中脂肪細胞與乳癌細胞的交互影響仍然未知，因此，本研究欲探討lunasin、aspirin或兩者合併處理能否抑制脂肪細胞的發炎反應、脂肪與乳癌細胞間的交互作用，進而抑制乳癌細胞的生長。結果顯示，lunasin的處理能顯著降低TNF-α誘發3T3-L1脂肪細胞IL-6與MCP-1的分泌，而aspirin的處理能降低脂肪細胞在巨噬細胞條件培養液培養下其IL-6與MCP-1的分泌。對於4T1乳癌細胞，aspirin的處理顯著具有細胞毒殺作用，並抑制MCP-1與VEGF的分泌。而lunasin、aspirin或兩者共同處理，有劑量效應地抑制4T1細胞的移行能力。在3T3-L1脂肪細胞條件培養液培養4T1細胞實驗中，證實隨著脂肪細胞培養液比例的增加，顯著刺激4T1細胞生長，而aspirin的處理能顯著抑制脂肪細胞所刺激的乳癌細胞增生和MCP-1與PAI-1的分泌。另外，建立3T3-L1與4T1細胞經通透膜共培養模式，來模擬脂肪細胞存在的腫瘤微環境，結果顯示aspirin可有效地抑制4T1細胞生長及MCP-1與PAI-1的分泌，而lunasin能增強aspirin抑制4T1細胞生長的效果。綜合而論，lunasin能降低3T3-L1脂肪細胞IL-6與MCP-1的分泌、抑制4T1乳癌細胞的移行能力，並增強aspirin在脂肪細胞存在下抑制4T1細胞生長的效果。而Aspirin分別有效降低脂肪細胞與乳癌細胞其IL-6、MCP-1、VEGF與PAI-1的分泌，並抑制乳癌細胞生長與移行能力，在共培養模式中調控腫瘤微環境中細胞激素的分泌，進而抑制乳癌細胞的增生。Aspirin或合併lunasin使用可能有助於乳癌患者的輔助治療，作為日常飲食的建議，其相關機轉值得進一步研究探討。

Breast cancer is one of the most common cancers in women worldwide. The obese process normally accompanies chronic and low grade inflammation. Inflammatory cytokines secretion and immune cells infiltration provide a favorable microenvironment for tumor growth, migration, and metastasis. Lunasin is a seeds peptide with 43-amino acids has been demonstrated its chemopreventive properties in many cancers. Aspirin is another chemopreventive agent has been shown against several types of cancer, but complicated gastrointestinal injury simultaneously. Recently, some studies used aspirin combined with other chemopreventive compounds to reduce its side effects, and achieve synergistic effects. The aim of this work is to investigate the anti-inflammatory and anti-cancer properties of lunasin, aspirin and their combination on 3T3-L1 adipocytes, 4T1 murine breast cancer cells and their cross-talk using co-culture system. The results were showed that lunasin and aspirin significantly inhibited IL-6 and MCP-1 productions in adipocytes induced by TNF-α and RAW 264.7 cells conditioned-medium. In 4T1 breast cancer cells, aspirin has significantly cellular cytotoxicity effect, but lunasin didn’t affect cell growth on 4T1 cells. In wound healing assay, treatments of lunasin, aspirin and their combination inhibited 4T1 cell migration. Futhermore, aspirin inhibited cytokine MCP-1, VEGF and PAI-1 secretions of 4T1 cell cultured with adipocytes conditioned-medium and then inhibited 4T1 cell growth. In co-culture system, aspirin exerted the inhibitory effects as well as in conditioned-medim model. In additional, lunasin treatment enhanced aspirin’s cytotoxicity effect on 4T1 in this system. Summary, lunasin and aspirin inhibited inflammatory cytokines productions of 3T3-L1 adipocytes, migration of 4T1 cells and cross-talk between these cells, might contribute to their chemopreventive properties on 4T1 breast cancer cells. This study indicated the potential application of lunasin and/or combined with aspirin in the auxiliary therapy of obese relative breast cancer, and more experiments should be carried out in the future.