Tumor Biology

, Volume 37, Issue 5, pp 6485–6491 | Cite as

Downregulation of pyrroline-5-carboxylate reductase-2 induces the autophagy of melanoma cells via AMPK/mTOR pathway

  • Rongying Ou
  • Xueqi Zhang
  • Jianfeng Cai
  • Xiaohong Shao
  • Mingfen Lv
  • Wei Qiu
  • Xuan Xuan
  • Jingjing Liu
  • Zhiming Li
  • Yunsheng Xu
Original Article


Melanoma is the most aggressive form of skin cancer and causes 50,000 deaths annually worldwide. The roles of proline-dependent process and autophagy have both been reported in studies on melanoma. In the present study, we focused on the effect of pyrroline-5-carboxylate reductase-2 (PYCR2) on inducing autophagy process in melanoma. The expression of PYCR2 was regulated by an RNAi technique, and the cell proliferation of A375 cell line was determined by methyl thiazolyl tetrazolium test; the effect of PYCR2 on the apoptosis process and AMPK/mTOR pathway was evaluated by flow cytometry assay and Western blot. It was found that silence of PYCR2 resulted in the decrease of proliferative ability and activation of AMPK/mTOR-induced autophagy of A375 cells. PYCR2 silencing also activated AMPK/mTOR pathway in another melanoma cell line, CHL-1. However, the overexpression of PYCR2 seemed to make no difference to the cell viability and targeted pathway. Our results offered a preliminary illustration on the mechanism of the PYCR2-dependent autophagy and showed that PYCR2 was a potential therapeutic target of melanoma.


Melanoma Pyrroline-5-carboxylate reductase-2 AMPK/mTOR Autophagy 



This work was supported by grants from the National Natural Science Foundation of China (No. 81272987, 81373075, 81371748).

Supplementary material

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Table S4 (DOCX 15 kb)


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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2015

Authors and Affiliations

  • Rongying Ou
    • 1
  • Xueqi Zhang
    • 2
  • Jianfeng Cai
    • 2
  • Xiaohong Shao
    • 2
  • Mingfen Lv
    • 2
  • Wei Qiu
    • 2
  • Xuan Xuan
    • 2
  • Jingjing Liu
    • 2
  • Zhiming Li
    • 2
  • Yunsheng Xu
    • 2
  1. 1.Department of Gynaecology and ObstetricsThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina
  2. 2.Department of Dermatovenerology, the First Affiliated Hospital of Wenzhou Medical University; Institute of DermatovenerologyWenzhou Medical UniversityWenzhouChina

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