Beta-Elemene Reduces the Malignancy of Non-Small Cell Lung Cancer by Enhancing C3orf21 Expression

Abstract

Background: Beta-elemene has potent anti-tumor effect, but its anti-tumor mechanism remains unclear. Chromosome 3 open reading frame 21 (C3orf21) acts as a tumor suppressor. This study tested whether the anti-tumor effect of beta-elemene was associated with modulating C3orf21 expression in non-small cell lung cancer (NSCLC).

Materials and methods: The impact of beta-elemene on C3orf21 expression in NSCLC cells was quantified. The stable C3orf21 silencing A549 and over-expressing PC-9 cells were established and their effects on the beta-elemene-attenuated proliferation, wound healing and invasion of NSCLC cells as well as the expression of key regulators and signal events were determined.

Results: Beta-elemene significantly up-regulated C3orf21 expression in NSCLC cells. Beta-elemene treatment significantly attenuated the proliferation, wound healing and invasion of NSCLC cells, which were significantly mitigated by C3orf21 silencing, but enhanced by C3orf21 over-expression. Similar patterns of beta-elemene-modulated cyclinD1, c-Myc, COX2, MMP2, MMP9, VEGF, PTEN and Notch1 expression were detected in NSCLC cells.

Conclusions: Such data indicated that beta-elemene treatment attenuated the malignancy of NSCLC cells by up-regulating C3orf21 expression. Our findings may provide new mechanisms underlying the pharmacological action of beta-elemene.

Keywords: C3orf21; elemene injection; malignancy; mechanisms; non-small cell lung cancer.

Figure 1

The structure of beta-elemene.

Figure 2

The network of beta-elemene with the potential targeted genes. green rhombus represents beta-elemene; blue ellipse represent the targeted genes of beta-elemene; red ellipse represent the XXYLT1.

Figure 3

A network of beta-elemene with the potential interacted proteins. Gray lines indicate protein-protein interactions; Green lines indicate compound–protein interactions.

Figure 4

C3orf21 expression in NSCLC cells. (A) Western blot analysis of the relative levels of C3orf21 expression in the indicated NSCLC cells. (B) Beta-elemene enhances C3orf21 expression in NSCLC cells. (C, D) Generation of C3orf21 stable silencing A549 cells and C3orf21 stable over-expressing PC-9 cells. Data are representative images or expressed as the mean ± SD of each group from three biological experiments. *P < 0.05, **P < 0.01 and ***P < 0.001 vs. the control.

Figure 5

Beta-elemene inhibits the proliferation of NSCLC cells. A549, PC-9, A549-shNC and A549-shC3orf21 cells were treated with, or without, the indicated concentrations of beta-elemene for 24 h and the cell proliferation was determined by CCK-8 assays. Data are expressed as the mean ± SD of each dose group from three biological experiments. (A, B) The proliferation of A549 cells. (B) The proliferation of PC-9 cells. (C) The proliferation of A549-shNC and A549-shC3orf21 cells. (D) The proliferation of PC-9-NC and PC-9-C3orf21 over-expression. *P < 0.05, **P < 0.01 and ***P < 0.001 vs. the control.

Figure 6

Beta-elemene attenuates the wound healing and invasion of NSCLC cells. (A) The wound healing of A549 cells. (B) The wound healing of PC-9 cells. (C) The invasion of A549 cells. (D) The invasion of PC-9 cells. Data are representative images or expressed as the mean ± SD of each group from three biological experiments. **P < 0.01 and ***P < 0.001 vs. the control.

Figure 7

Beta-elemene modulates the expression of several regulators and signal events in NSCLC cells, dependent on C3orf21 expression. The indicated NSCLC cells were treated with, or without, beta-elemene for 24 h and the relative levels of MMP-2 (A), MMP-9 (B), VEGF (C), PTEN (D) Cyclin (E), C-Myc (F), and COX2 (G) in the indicated NSCLC cells were quantified by RT-PCR. Data are present as mean ± SD of each group from at least three biological experiments. **P < 0.01 and ***P < 0.001 vs. the control.

Figure 8

Beta-elemene decreases C3orf21 protein expression in NSCLC cells. The indicated NSCLC cells were treated with, or without, beta-elemene for 24 and their relative levels of Notch1 protein expression (A, B) were quantified by Western blot. Data are representative images or present as mean ± SD of each group from at least three biological experiments. **P < 0.01 and ***P < 0.001 vs. the control.