title: Long non-coding RNA FOXP4-AS1 is an unfavourable prognostic factor and regulates proliferation and apoptosis in colorectal cancer.
abstract: OBJECTIVE
  Despite improvements in diagnosis and treatment, colorectal cancer (CRC) remains the third most common malignancy, and fourth-leading cause of cancer-related death worldwide, and has a particularly high incidence in Western countries. Recent studies have suggested that long non-coding RNAs (lncRNAs) compose a novel class of regulators of cancer biological processes, such as proliferation, apoptosis and metastasis. Here, we report that lncRNA FOXP4-AS1 acts as a functional oncogene in CRC pathogenesis. Moreover, we have attempted to investigate the effects of FOXP4-AS1 on tumour progression, both in vitro and in vivo.
  
  
  METHODS
  In this study, bioinformatic analyses and qPCR were performed to investigate FOXP4-AS1 expression in CRC tissue samples and CRC cell lines. We inhibited FOXP4-AS1 expression via FOXP4-AS1-specific siRNA transfection. Cell proliferation was assessed using cell viability and colony formation assays, as well as by flow cytometry and ethynyl deoxyuridine (Edu) analyses. Apoptosis was assessed using flow cytometry. Animal tumour xenografts were generated, and immunohistochemistry (IHC) was performed to evaluate effects of FOXP4-AS1 on CRC tumour growth in vivo.
  
  
  RESULTS
  We found that FOXP4-AS1 was up-regulated in CRC tissues and cell lines and that its overexpression positively correlated with advanced pathological stages and larger tumour size. Additionally, we found that FOXP4-AS1 knockdown inhibited cell proliferation and induced apoptosis. Furthermore, FOXP4-AS1 knockdown induced marked increase in number of cells in G0/G1 phase and reduction in number of cells in S phase, in DLD-1, HT-29 and HCT116 cell lines. Consistent with these findings, FOXP4-AS1 silencing inhibited tumour growth in vivo.
  
  
  CONCLUSIONS
  These findings suggest that FOXP4-AS1 plays a crucial role in CRC progression and may be a new biomarker in patients with CRC.
authors: The Second Clinical Medical College of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Juan
authors: J
authors: Li
authors: The Second Clinical Medical College of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Yifan
authors: Y
authors: Lian
authors: Department of Obstetrics and Gynecology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Changsheng
authors: C
authors: Yan
authors: Department of General Surgery, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Zeling
authors: Z
authors: Cai
authors: Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Jie
authors: J
authors: Ding
authors: Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Zhonghua
authors: Z
authors: Ma
authors: Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Peng
authors: P
authors: Peng
authors: The Second Clinical Medical College of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: Keming
authors: K
authors: Wang
mesh_terms: D000368:Aged; D000818:Animals; D017209:Apoptosis / Q000235:genetics*; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D059585:G1 Phase Cell Cycle Checkpoints; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011379:Prognosis; D034622:RNA Interference; D062085:RNA, Long Noncoding / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D014183:Transplantation, Heterologous; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; C000613931:FOXP4 antisense RNA 1, human; D062085:RNA, Long Noncoding; D034741:RNA, Small Interfering
keywords: FOXP4-AS1; TNM stage; apoptosis; colorectal cancer; lncRNA; proliferation