The combination of an mTORc1/TORc2 inhibitor with lapatinib is synergistic in bladder cancer in vitro.
The combination of an mTORc1/TORc2 inhibitor with lapatinib is synergistic in bladder cancer in vitro.
复制标题
DOI：
10.1016/j.urolonc.2013.06.002
复制
发表时间：
2014-04
期刊：
影响因子：
--
通讯作者：
Williams CR
中科院分区：
文献类型：
--
作者：
Becker MN;Wu KJ;Marlow LA;Kreinest PA;Vonroemeling CA;Copland JA;Williams CR
检查双重mTORc 1/c2抑制剂与拉帕替尼联合使用以协同方式抑制膀胱癌细胞系中细胞增殖和锚定非依赖性生长的能力。我们使用包含84个病例的组织微阵列检测了患者肿瘤样本中pS 6、p4 EBP 1、pAkt和磷酸化表皮生长因子受体（pEGFR）的过表达。分析了三种膀胱癌细胞系T24、HT 1376和UM-UC-3在用mTORc 1/c2抑制剂OSI-027或PP 242处理后的细胞增殖。蛋白质印迹用于验证药物抑制mTOR通路中靶蛋白的磷酸化，并将其与雷帕霉素抑制进行比较。我们还分析了用OSI-027和拉帕替尼组合处理后的细胞增殖和锚定非依赖性生长。PARP裂解和自噬通量通过检测LC 3B和p62的蛋白质印迹水平来测量。相对于正常组织，肿瘤样品显示pEGFR（38%对8%）和HER 2（38%对4%）的表达增加以及pAkt S473（7.5%对29%）和pAkt T308（50%对84%）的表达减少。在正常和肿瘤样品之间观察到用pEGFR（P = 0.0188）、HER 2（P = 0.0017）、pATK S473（P = 0.0128）和pAkt T308（P = 0.0015）染色的显著差异。EGFR/HER 2通路或mTOR通路内的蛋白质表达是相关的。染色与肿瘤分期无相关性。OSI-027和PP 242可抑制所有3种细胞系的细胞增殖，IC 50值范围为0.63 - 17.95 μM。这两种药物都抑制mTORc 1和mTORc 2途径成分的磷酸化。OSI-027和拉帕替尼以协同方式抑制细胞增殖和锚定非依赖性生长。一种细胞系响应于组合药物处理而表现出凋亡，而其他2种细胞系具有指示对凋亡的抗性的增加的自噬水平。OSI-027和拉帕替尼的组合导致抗肿瘤协同作用，并且应该进行这种组合的进一步探索。
To examine the ability of dual mTORc1/c2 inhibitors in conjunction with lapatinib to function in a synergistic manner to inhibit cell proliferation and anchorage-independent growth in bladder cancer cell lines. We examined patient tumor samples for overexpression of pS6, p4EBP1, pAkt, and phosphorylated epidermal growth factor receptor (pEGFR) using a tissue microarray containing 84 cases. Three bladder cancer cell lines, T24, HT1376, and UM-UC-3, were analyzed for cell proliferation after treatment with mTORc1/c2 inhibitors OSI-027 or PP242. Western blots were used to verify that the drugs were inhibiting phosphorylation of target proteins within the mTOR pathway, and they were compared with rapamycin inhibition. We also analyzed cell proliferation and anchorage-independent growth after treatment with OSI-027 and lapatinib in combination. PARP cleavage and autophagic flux were measured by examining levels of LC3B and p62 by western blotting. Tumor samples show increased expression of pEGFR (38% vs. 8%) and HER2 (38% vs. 4%) and decreased expression of pAkt S473 (7.5% vs. 29%) and pAkt T308 (50% vs. 84%) relative to normal tissue. Significant differences between normal and tumor samples for staining with pEGFR (P = 0.0188), HER 2 (P = 0.0017), pATK S473 (P = 0.0128), and pAkt T308 (P = 0.0015) is observed. Expression of proteins within the EGFR/HER2 pathway or within the mTOR pathway is correlated. No correlation was found between staining and tumor stage. OSI-027 and PP242 diminish cell proliferation in all 3 cell lines with IC50 values ranging from 0.63 to 17.95 μM. Both drugs inhibit phosphorylation of both mTORc1 and mTORc2 pathway components. OSI-027 and lapatinib inhibit cell proliferation and anchorage-independent growth in a synergistic manner. One cell line exhibited apoptosis in response to combination drug treatment, whereas the other 2 cell lines have increased levels of autophagy indicative of resistance to apoptosis. The combination of OSI-027 and lapatinib results in antitumor synergy and further exploration of this combination should be undertaken.