Richmond Craig S, Oldenburg Darby, Dancik Garrett, Meier David R, Weinhaus Benjamin, Theodorescu Dan, Guin Sunny
Medical Research, Gundersen Medical Foundation, La Crosse, WI, USA.
Department of Mathematics and Computer Science, Eastern Connecticut State University, Willimantic, CT, USA.
Oncotarget. 2018 Mar 30;9(24):16718-16730. doi: 10.18632/oncotarget.24676.
Glycogen debranching enzyme (AGL) and Glycogen phosphorylase (PYG) are responsible for glycogen breakdown. We have earlier shown that AGL is a regulator of bladder tumor growth. Here we investigate the role of AGL in non-small cell lung cancers (NSCLC). Short hairpin RNA (shRNA) driven knockdown of AGL resulted in increased anchorage independent and xenograft growth of NSCLC cells. We further establish that an increase in hyaluronic acid (HA) synthesis driven by Hyaluronic Acid Synthase 2 (HAS2) is critical for anchorage independent growth of NSCLC cells with AGL loss. Using gene knockdown approach against HAS2 and by using 4-methylumbelliferone (4MU), an inhibitor of HA synthesis, we show that HA synthesis is critical for growth of NSCLC cells that have lost AGL. We further show NSCLC cells without AGL expression are dependent on RHAMM for HA signaling and growth. Analysis of NSCLC patient datasets established that patients with low AGL/high HAS2 or low AGL/high RHAMM mRNA expression have poor overall survival compared to patients with high AGL/low HAS2 or high AGL/low RHAMM expression. We show for the first time that loss of AGL promotes anchorage independent growth of NSCLC cells. We further show that HAS2 driven HA synthesis and signaling via RHAMM is critical in regulating growth of these cancer cells with AGL loss. Further patients presenting with low AGL and HAS2 or RHAMM over expressing tumors might present the ideal cohort who would respond to inhibitors of HA synthesis and signaling.
糖原脱支酶(AGL)和糖原磷酸化酶(PYG)负责糖原分解。我们之前已经表明AGL是膀胱肿瘤生长的调节因子。在此,我们研究AGL在非小细胞肺癌(NSCLC)中的作用。短发夹RNA(shRNA)介导的AGL敲低导致NSCLC细胞的非锚定依赖性生长和异种移植生长增加。我们进一步证实,由透明质酸合酶2(HAS2)驱动的透明质酸(HA)合成增加对于AGL缺失的NSCLC细胞的非锚定依赖性生长至关重要。通过针对HAS2的基因敲低方法以及使用HA合成抑制剂4-甲基伞形酮(4MU),我们表明HA合成对于已失去AGL的NSCLC细胞的生长至关重要。我们进一步表明,不表达AGL的NSCLC细胞依赖于RHAMM进行HA信号传导和生长。对NSCLC患者数据集的分析表明,与高AGL/低HAS2或高AGL/低RHAMM表达的患者相比,低AGL/高HAS2或低AGL/高RHAMM mRNA表达的患者总生存期较差。我们首次表明AGL缺失促进NSCLC细胞的非锚定依赖性生长。我们进一步表明,HAS2驱动的HA合成以及通过RHAMM的信号传导对于调节这些AGL缺失的癌细胞的生长至关重要。此外,呈现低AGL且HAS2或RHAMM过表达肿瘤的患者可能是对HA合成和信号传导抑制剂有反应的理想人群。