Inhibition of B7-H3 reverses oxaliplatin resistance in human colorectal cancer cells

Biochem Biophys Res Commun. 2017 Aug 26;490(3):1132-1138. doi: 10.1016/j.bbrc.2017.07.001. Epub 2017 Jul 1.

Abstract

B7-H3, an immunoregulatory protein, has been found highly expressed in several cancer types, and involved in cancer cell migration and invasion. Here, we investigated the role of B7-H3 in oxaliplatin resistance in colorectal cancer (CRC) cells. Transient silencing of B7-H3 enhanced oxaliplatin sensitivity by increasing oxaliplatin-induced DNA damage. The overexpression of B7-H3 increased oxaliplatin resistance reducing the formation of phosphorylated histone H2AX (γH2AX) loci. The silencing of X-ray repair cross complementing group 1 (XRCC1), upregulated in B7-H3 overexpressing cells, induced an increase in cell death following oxaliplatin treatment. Finally, the upregulation of XRCC1 expression induced by B7-H3 involved PI3K-AKT pathway. In conclusion, B7-H3 promotes the oxaliplatin resistance in CRC cells upregulating the expression of XRCC1 via PI3K-AKT pathway.

Keywords: B7-H3; Colorectal cancer; Oxaliplatin resistance; PI3K-AKT pathway; XRCC1.

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • B7 Antigens / genetics*
  • Cell Line, Tumor
  • Colon / drug effects
  • Colon / metabolism
  • Colon / pathology
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / genetics
  • Colorectal Neoplasms / metabolism
  • Colorectal Neoplasms / pathology
  • DNA-Binding Proteins / genetics
  • Drug Resistance, Neoplasm*
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • Organoplatinum Compounds / pharmacology*
  • Oxaliplatin
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA Interference*
  • RNA, Small Interfering / genetics
  • Rectum / drug effects
  • Rectum / metabolism
  • Rectum / pathology
  • Signal Transduction / drug effects
  • X-ray Repair Cross Complementing Protein 1

Substances

  • Antineoplastic Agents
  • B7 Antigens
  • CD276 protein, human
  • DNA-Binding Proteins
  • Organoplatinum Compounds
  • RNA, Small Interfering
  • X-ray Repair Cross Complementing Protein 1
  • XRCC1 protein, human
  • Oxaliplatin
  • Phosphatidylinositol 3-Kinases
  • Proto-Oncogene Proteins c-akt