A Recombinant Fragment of Human Surfactant Protein D induces Apoptosis in Pancreatic Cancer Cell Lines via Fas-Mediated Pathway

Front Immunol. 2018 Jun 4;9:1126. doi: 10.3389/fimmu.2018.01126. eCollection 2018.

Abstract

Human surfactant protein D (SP-D) is a potent innate immune molecule, which is emerging as a key molecule in the recognition and clearance of altered and non-self targets. Previous studies have shown that a recombinant fragment of human SP-D (rfhSP-D) induced apoptosis via p53-mediated apoptosis pathway in an eosinophilic leukemic cell line, AML14.3D10. Here, we report the ability of rfhSP-D to induce apoptosis via TNF-α/Fas-mediated pathway regardless of the p53 status in human pancreatic adenocarcinoma using Panc-1 (p53mt), MiaPaCa-2 (p53mt), and Capan-2 (p53wt) cell lines. Treatment of these cell lines with rfhSP-D for 24 h caused growth arrest in G1 cell cycle phase and triggered transcriptional upregulation of pro-apoptotic factors such as TNF-α and NF-κB. Translocation of NF-κB from the cytoplasm into the nucleus of pancreatic cancer cell lines was observed via immunofluorescence microscopy following treatment with rfhSP-D as compared to the untreated cells. The rfhSP-D treatment caused upregulation of pro-apoptotic marker Fas, as analyzed via qPCR and western blot, which then triggered caspase cascade, as evident from cleavage of caspase 8 and 3 analyzed via western blot at 48 h. The cell number following the rfhSP-D treatment was reduced in the order of Panc-1 (~67%) > MiaPaCa-2 (~60%) > Capan-2 (~35%). This study appears to suggest that rfhSP-D can potentially be used to therapeutically target pancreatic cancer cells irrespective of their p53 phenotype.

Keywords: apoptosis; immune surveillance; innate immunity; pancreatic cancer; surfactant protein D.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / drug effects*
  • Apoptosis / genetics
  • Caspase 3 / metabolism
  • Caspase 8 / metabolism
  • Cell Cycle Checkpoints / drug effects
  • Cell Cycle Checkpoints / genetics
  • Cell Line, Tumor
  • Humans
  • NF-kappa B / metabolism
  • Pancreatic Neoplasms / metabolism*
  • Peptide Fragments / pharmacology*
  • Protein Transport
  • Pulmonary Surfactant-Associated Protein D / chemistry
  • Pulmonary Surfactant-Associated Protein D / pharmacology*
  • Recombinant Proteins
  • Signal Transduction / drug effects*
  • TOR Serine-Threonine Kinases / metabolism
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism
  • fas Receptor / genetics
  • fas Receptor / metabolism*

Substances

  • NF-kappa B
  • Peptide Fragments
  • Pulmonary Surfactant-Associated Protein D
  • Recombinant Proteins
  • Tumor Suppressor Protein p53
  • fas Receptor
  • TOR Serine-Threonine Kinases
  • Caspase 3
  • Caspase 8

Supplementary concepts

  • Pancreatic Carcinoma