School of Pharmaceutical Sciences, Southwest University, Chongqing, 400716, China.
McLean Hospital, Harvard Medical School, Belmont, 02478, MA, USA.
Sci Rep. 2019 Jan 16;9(1):146. doi: 10.1038/s41598-018-29099-x.
SPG-56 is a newly isolated glycoprotein from sweet potatoes (Zhongshu NO. 1), but its value for suppressing breast cancer progression remains unknown. This study was designed to investigate the potential anti-cancer effects of SPG-56, which consists of 2.9% sugar and 97.1% protein. The effects of SPG-56 on the proliferation and apoptosis of breast cancer cells were determined using CCK-8 and Hoechst 33342 assays and flow cytometry, after staining with Annexin V and PI respectively. The activities of SPG-56 against breast cancer were examined using female BALB/c nude mice orthotopically implanted with human breast carcinoma cells of the types MCF-7 and 4T1-Luc. The cellular experiments showed that SPG-56 inhibited proliferation and promoted apoptosis of MCF-7 cells dose- and time-dependently. Oral administration of SPG-56 significantly suppressed the development of MCF-7 tumor cells (P < 0.01) as compared with an untreated group. The serum tumor markers CEA, CA125 and CA153 in a 240 mg/kg/d SPG-56 decreased by 54.8%, 91.8%, and 90.3%, respectively. The experiments further demonstrated that SPG-56 inhibited the metastasis of breast cancer in MCF-7 and 4T1-bearing mice by altering the expression of MMP2, MMP9, VEGF, Occludin and Claudin. It is concluded that SPG-56 may have potential as a novel anti-tumor candidate for breast cancer.
SPG-56 是从甘薯（中薯 1 号）中分离得到的一种新的糖蛋白，但它抑制乳腺癌进展的价值尚不清楚。本研究旨在探讨 SPG-56 的潜在抗癌作用，SPG-56 由 2.9%的糖和 97.1%的蛋白质组成。分别用 Annexin V 和 PI 染色后，通过 CCK-8 和 Hoechst 33342 测定法和流式细胞术测定 SPG-56 对乳腺癌细胞增殖和凋亡的影响。通过将人乳腺癌细胞 MCF-7 和 4T1-Luc 原位植入雌性 BALB/c 裸鼠来检查 SPG-56 对乳腺癌的作用。细胞实验表明，SPG-56 呈剂量和时间依赖性地抑制 MCF-7 细胞的增殖并促进其凋亡。与未治疗组相比，SPG-56 的口服给药显著抑制 MCF-7 肿瘤细胞的发展（P<0.01）。SPG-56（240mg/kg/d）治疗组的血清肿瘤标志物 CEA、CA125 和 CA153 分别降低了 54.8%、91.8%和 90.3%。实验进一步表明，SPG-56 通过改变 MMP2、MMP9、VEGF、Occludin 和 Claudin 的表达抑制 MCF-7 和 4T1 荷瘤小鼠的乳腺癌转移。综上所述，SPG-56 可能是一种新型的乳腺癌抗肿瘤候选药物。
