Lentivirus-mediated TPD52L2 depletion inhibits the proliferation of liver cancer cells in vitro

Abstract

Tumor protein D52-like 2, known as hD54 in previous studies (TPD52L2), is a member of TPD52 family which has been implicated in multiple human cancers. In recent reports, TPD52 proteins were indicated to be associated with several malignancies, but very little is known about the function of TPD52L2 in liver cancers. In our present study, in order to explore the role of TPD52L2 in liver cancer, TPD52L2 was knocked down in SMMC-7721 liver cancer cell line by lentivirus mediated RNA interference. The results demonstrated that depletion of TPD52L2 could remarkably inhibit proliferation and colony forming ability of cancer cell SMMC-7721. Furthermore, cell cycle in TPD52L2 depleted cells was verified to be arrested in G0/G1 phase as determined by FACS assay, in consistence with the observation of cell proliferation inhibition. These results unraveled that TPD52L2 played an important role in tumorigenesis pathways of liver cancer and might serve as a promising target in human liver cancer diagnosis and therapy.

Keywords: RNA interference; TPD52L2; lentivirus; liver cancer; proliferation.

Figure 1

Lentivirus infection and knockdown efficiency of SMMC-7721 cells. A: Bright field and fluorescence photomicrographs after transduction of SMMC-7721 cells in Con, shCon and shTPD52L2 groups respectively. Over 80% of cells were infected with lentivirus by visualized GFP expression. Scale bar: 100 µm. B: Relative expression level of TPD52L2 in SMMC-7721 cells with quantitative PCR. **P < 0.01, compared to shCon. C: Western blot analysis of TPD52L2 to present a satisfying knockdown efficiency.

Figure 2

Colony formation ability and proliferation rate of SMMC-7721 cells with TPD52L2 silencing. A: Line chart of MTT assay by optical density at 595 nm of SMMC-7721 cells in Con, shCon and shTPD52L2 groups respectively. ***P < 0.001, compared to shCon. B: The colony formation of SMMC-7721 cells in Con, shCon and shTPD52L2 groups viewing under bright field, crystal violet, fluorescent field (Scale bar: 250 µm), and six-well plate respectively. C: The statistical analysis of colony numbers in Con, shCon and shTPD52L2 groups. ***P < 0.001, compared to shCon.

Figure 3

Depletion of TPD52L2 triggered G0/G1 cell cycle arrest. A: Cell cycle distribution of SMMC-7721 cells by flow cytometry in Con, shCon and shTPD52L2 groups respectively. B: Cell population under different stages of G0/G1, S, G2/M phase. ***P < 0.001, compared to shCon. C: Variant distribution of SMMC-7721 cells of Con, shCon, and shTPD52L2 in sub-G1 phase. **P < 0.01, compared to shCon.