Vinblastine differs from Taxol as it inhibits the malignant phenotypes of NSCLC cells by increasing the phosphorylation of Op18/stathmin

Oncol Rep. 2017 Apr;37(4):2481-2489. doi: 10.3892/or.2017.5469. Epub 2017 Feb 20.

Abstract

Taxol (paclitaxel) and vinblastine (VBL) are both efficacious chemotherapeutic agents that target the microtubules of tumor cells, but each functions in a mutual antagonistic manner. Op18/stathmin is a small molecular phosphoprotein which promotes depolymerization of microtubules. Non-small cell lung cancer (NSCLC) NCI-H1299 cells were employed to compare the curative effects of VBL and Taxol and explore the correlation between drug sensitivity and Op18/stathmin signaling. The present study found that VBL obviously promoted cellular apoptosis and initiated activation of caspase 3 and 9, and inhibited cell proliferation and colony formation, as well as cell migration in the NCI-H1299 cells in contrast with Taxol. VBL did not affect the expression of Op18/stathmin, but increased its phosphorylation at all 4 serine sites. Conversely, Taxol mainly decreased the expression of Op18/stathmin and the phosphorylation at Ser25 and Ser63 sites. Silencing of Op18/stathmin by RNA interference (RNAi) led to a great reduction in the differences in the cell proliferation inhibition between VBL and Taxol. VBL treatment notably weakened the expression of PP2A, Bcl-2, NF-κB and interleukin-10 (IL-10) and autocrine IL-10 compared with Taxol; whereas PP2A was substantially increased following Taxol induction. High expression of Op18/stathmin was found to be negatively correlated with the sensitivity of Taxol in the NSCLC cells, but had a minor impact on VBL cytotoxicity. These findings revealed that both VBL and Taxol induce cell apoptosis through Op18/stathmin, but the mechanisms are completely different. VBL is an attractive alternative to the treatment of Taxol-resistant tumors with high expression of Op18/stathmin.

Publication types

  • Comparative Study

MeSH terms

  • Apoptosis
  • Carcinoma, Non-Small-Cell Lung / metabolism*
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • Lung Neoplasms / metabolism*
  • Paclitaxel / pharmacology*
  • Phosphorylation / drug effects
  • Stathmin / metabolism*
  • Vinblastine / pharmacology*

Substances

  • Stathmin
  • Vinblastine
  • Paclitaxel