Octreotide-Paclitaxel Conjugate Reverses Paclitaxel Resistance by p38 Mitogen-Activated Protein Kinase (MAPK) Signaling Pathway in A2780/Taxol Human Ovarian Cancer Cells

Med Sci Monit. 2020 Aug 23:26:e922612. doi: 10.12659/MSM.922612.

Abstract

BACKGROUND Platinum plus paclitaxel is a first-line chemotherapy for ovarian cancer. Platinum resistance is a hot topic for many scholars, but drug resistance caused by paclitaxel is also a topic of concern. Currently, scholars believe that inhibition of MAPK signaling pathway may be an effective way to reverse the drug resistance of tumor paclitaxel. MATERIAL AND METHODS A2780/Taxol cells or nude mice were divided into 8 groups: control group, OCT (octreotide) group, OC (octreotide+cyclosomatostatin) group, PTX (paclitaxel) group, PO (paclitaxel+octreotide) group, POC (paclitaxel+octreotide+cyclosomatostatin) group, P-O (octreotide-paclitaxel conjugate) group, and P-OC (octreotide-paclitaxel conjugate+cyclosomatostatin) group. The phosphorylation level of p38 MAPK and the expression level of vascular endothelial growth factor (VEGF) were determined by western blot. Flow cytometry was used to discover the apoptosis of A2780/Taxol cells and xenografts. The expression of class III beta-tubulin was detected by immunohistochemistry. RESULTS Octreotide-paclitaxel conjugate inhibited phosphorylation of the p38MAPK signal pathway, decreased the expression of downstream VEGF, and increased the apoptosis of drug-resistant cancer cells. In addition, it reduced the expression of class III beta-tubulin protein and increase the sensitivity of drug-resistant cells to paclitaxel. All these effects of octreotide-paclitaxel conjugate were cancelled by cyclosomatostatin. CONCLUSIONS Octreotide-paclitaxel conjugate can reverse the paclitaxel resistance of A2780/Taxol human ovarian cancer cells by inhibiting the activity of p38 MAPK signaling pathway.

MeSH terms

  • Animals
  • Antineoplastic Agents, Hormonal / pharmacology*
  • Antineoplastic Agents, Hormonal / therapeutic use
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Antineoplastic Agents, Phytogenic / therapeutic use
  • Apoptosis / drug effects
  • Cell Line, Tumor
  • Drug Resistance, Neoplasm / drug effects*
  • Female
  • Humans
  • MAP Kinase Signaling System / drug effects*
  • Mice
  • Mice, Nude
  • Octreotide / pharmacology*
  • Octreotide / therapeutic use
  • Ovarian Neoplasms / drug therapy
  • Ovarian Neoplasms / metabolism*
  • Ovarian Neoplasms / pathology
  • Paclitaxel / pharmacology*
  • Paclitaxel / therapeutic use
  • Peptides, Cyclic / pharmacology
  • Phosphorylation / drug effects
  • Taxoids / pharmacology*
  • Taxoids / therapeutic use
  • Tubulin / metabolism
  • Tumor Burden / drug effects
  • Vascular Endothelial Growth Factor A / metabolism
  • Xenograft Model Antitumor Assays
  • p38 Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Antineoplastic Agents, Hormonal
  • Antineoplastic Agents, Phytogenic
  • Peptides, Cyclic
  • TUBB3 protein, human
  • Taxoids
  • Tubulin
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • cyclosomatostatin
  • octreotide-conjugated paclitaxel
  • vascular endothelial growth factor A, mouse
  • p38 Mitogen-Activated Protein Kinases
  • Paclitaxel
  • Octreotide