www.impactjournals.com/oncotarget/ Oncotarget, 2017, Vol. 8, (No. 64), pp: 107932-107946 Research Paper NCOA5 promotes proliferation, migration and invasion of colorectal cancer cells via activation of PI3K/AKT pathway Kailv Sun1,*, Sheng Wang1,*, Jun He1,*, Yufeng Xie2, Yang He3,4, Zhenxin Wang2 and Lei Qin1 1Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China 2Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, China 3Ministry of Health Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China 4Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China *These authors have contributed equally to this work Correspondence to: Lei Qin, email: [email protected] Zhenxin Wang, email: [email protected] Yufeng Xie, email: [email protected] Keywords: nuclear receptor coactivator 5 (NCOA5); colorectal cancer (CRC); proliferation; metastasis; phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT) pathway Received: October 27, 2016 Accepted: July 25, 2017 Published: November 14, 2017 Copyright: Sun et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. ABSTRACT The nuclear receptor coactivator 5 (NCOA5) displays both coactivator and corepressor functions. Previous studies showed that alteration of NCOA5 participates in carcinogenesis and progression. However, its roles in colorectal cancer (CRC) remain unknown. Herein, we demonstrated that expression of NCOA5 in human CRC tissues was notably higher than that in adjacent tissues, which significantly correlated with clinicopathological features such as length of tumor, regional lymph node staging and cancer staging. Knockdown of NCOA5 markedly suppressed proliferation, migration and invasion of SW620 high malignant CRC cells. Silencing of NCOA5 also inhibited in vivo growth of SW620 CRC subcutaneously xenografted tumors in athymic BALB/c nude mice. Meanwhile, Overexpression of NCOA5 facilitated these processes in SW480 low malignant CRC cells. Furthermore, knockdown of NCOA5 induced cell cycle G1 phase arrest in SW620 cells, whereas overexpression of NCOA5 promoted G1 to S phase transition in SW480 cells. Mechanistic studies revealed that NCOA5 upregulated phospho-protein kinase B (p-PKB/AKT), Cyclin D1 and matrix metalloproteinase 9 (MMP9) as well as downregulated P27 in CRC cells. Notably, PI3K inhibitor LY294002 obviously attenuated the effects of NCOA5 on p-AKT, Cyclin D1, P27 and MMP9. Moreover, LY294002 and knockdown of Cyclin D1 or MMP9 remarkably blocked the tumor-promoting activity of NCOA5. Collectively, NCOA5 promoted CRC cell proliferation, migration and invasion by upregulating Cyclin D1 and MMP9 while downregulating P27 to a great extent via activating PI3K/AKT signaling pathway. These findings suggested that NCOA5 exhibits an oncogenic effect in human CRC and represents a novel therapeutic target for CRC. www.impactjournals.com/oncotarget 107932 Oncotarget INTRODUCTION and overexpression, and also elucidated the potential molecular mechanisms. Colorectal cancer (CRC) is the second most commonly diagnosed malignancy in women and the RESULTS third in men worldwide, which is one of the leading causes of cancer-related mortality [1]. Approximately NCOA5 is upregulated in CRC clinical samples 1.4 million new cases and 693,900 deaths occurred in and correlated with clinicopathological features global in 2012 [1]. The prognosis and overall survival of CRC of CRC still remains poor due to late diagnosis and metastasis [2]. Accumulating alteration of oncogenes and To characterize its expression pattern in CRC, the tumor suppressor genes as well as dysregulated signaling expression of NCOA5 in human CRC tumor tissues and pathways are crucial for tumorgenesis and progression of adjacent non-cancerous normal tissues was evaluated CRC. Although recent advances in molecular biology have by immunohistochemistry analysis (Figure 1A). led to an increased knowledge of mechanisms responsible Immunohistochemical NCOA5 expression was available for CRC, only a limited number of critical molecules in all the 70 CRC cases. Among these CRC tumor tissue those have clinicopathological significance in CRC have samples, fifty-five cases (78.6%) showed high expression been discovered. Therefore, seeking other master genes of NCOA5 (32 samples scored “+++”, and 23 samples involved in CRC progression may help to provide more scored “++”) and fifteen cases showed low expression of reliable therapeutic targets and improve prognosis of CRC. NCOA5 (13 samples scored “+”, and 2 samples scored The nuclear receptor coactivator 5 (NCOA5), “-”). In contrast, NCOA5 was markedly decreased or also known as coactivator independent of AF2 (CIA), not detected in the adjacent non-cancerous tissues. The is a coregulator for α and β estrogen receptors and RVR expression of NCOA5 in human CRC clinical tissues was (NR1D2) orphan nuclear receptor [3]. NCOA5 contains further confirmed by Western blot (Figure 1B) and qRT- both LxxLL coactivator and ФxxФФ corepressor motifs, PCR (Figure 1C) (P<0.01) analysis. To assess the clinical which exerts coactivator and corepressor effects [3–6]. significance of NCOA5 in CRC, the relationship between Functionally, NCOA5 can interact with ERα and ERβ, NCOA5 expression and clinicopathological features thus enhancing their transcription activities [3, 4]. In was investigated. As shown in Table 1, high expression addition, NCOA5 as a corepressor can cooperate with of NCOA5 was notably associated with the length of TIP30 tumor suppressor and subsequently inhibit ERα- tumor (P<0.001), regional lymph node staging (P=0.005) induced c-myc transcription [5]. NCOA5 also functions and cancer staging (P=0.018), suggesting that NCOA5 as an LXR corepressor to attenuate expression of ATP- positively modulates malignant progression of CRC. binding cassette subfamily A member 1 (ABCA1) [6]. Although no statistical significance (P=0.145) was found, Interestingly, a previous study [7, 8] revealed that NCOA5 well-differentiated tumor was less frequently occurred in insufficiency increases the risk of both glucose intolerance the high-expression group than that occurred in the low- and inflammatory phenotype, resulting in the development expression group (Table 1). of hepatocellular carcinoma (HCC). Furthermore, reduced NCOA5 expression is frequently found in HCC [7]. Other Lentivirus-mediated NCOA5 knockdown and research [9] also found that NCOA5 is decreased in overexpression in CRC cells esophageal squamous cell carcinoma (ESCC), which is associated with its progression and a potential biomarker We firstly determined the expression level of in predicting poor prognosis. Conversely, NCOA5 has NCOA5 in five different human CRC cell lines (HT29, been found to be upregulated in luminal breast cancer HCT8, HCE8693, SW620 and SW480). Among them, and associated with lower overall survival [10]. These SW620 is a highly malignant and metastatic CRC cell reports indicated that alteration of NCOA5 contributes to line which derived from metastases. As shown in Figure carcinogenesis and cancer progression. 2A, the highest expression of NCOA5 was found in However, the roles of NCOA5 in human cancers SW620 cells (P<0.01), whereas the lowest expression are largely unknown. The expression pattern and of NCOA5 was found in SW480 cells (P<0.05 or 0.01). biological effects of NCOA5 in CRC have not been Thus, we selected SW620 and SW480 CRC cells for our reported. In the present study, we thus detected the next loss-of-function and gain-of-function researches expression of NCOA5 in human CRC clinical tissues by lentivirus-mediated NCOA5 shRNA knockdown and and cell lines, and then analyzed the relationship between overexpression, respectively. Fluorescence microscopic NCOA5 expression in CRC and its clinical implication. analysis (Figure 2B) showed that almost all of the NCOA5 Furthermore, we investigated the effects of NCOA5 on shRNA- or NCOA5-expressing lentivirus-transduced CRC cell proliferation, migration and invasion in vitro and corresponding control lentivirus-transduced SW620 and CRC subcutaneously (s.c.) xenografted tumor growth or SW480 CRC cells exhibited GFP expression. Flow in vivo by lentivirus-mediated NCOA5 knockdown cytometric analysis (Figure 2C) further quantitatively www.impactjournals.com/oncotarget 107933 Oncotarget demonstrated more than 90% GFP-positive cells in the Knockdown of NCOA5 inhibits CRC cell above lentivirus-transduced SW620 or SW480 cells. proliferation and induces cell cycle G1 phase The lentivirus-mediated knockdown or overexpression arrest, whereas overexpression of NCOA5 of NCOA5 in SW620 or SW480 CRC cells was then enhances its proliferation and G1 to S phase analyzed by Western blot. As shown in Figure 2D, SW620 transition cells displayed a drastic reduction in the expression of NCOA5 after transduced by NCOA5 shRNAs (shNCOA5 To investigate the biological role of NCOA5 in CRC 1#, shNCOA5 2# and shNCOA5 3#) compared with cell growth, the in vitro proliferation ability of NCOA5- that transduced by shNTC (P<0.01). Moreover, the silenced SW620 and NCOA5-overexpressed SW480 silencing efficiency of shNCOA5 2# and shNCOA5 3# tumor cells was determined by a CCK-8 assay. As shown was up to around 90%,