RBPJ and MAML3: Potential Therapeutic Targets for Small Cell Lung Cancer

Anticancer Res. 2018 Aug;38(8):4543-4547. doi: 10.21873/anticanres.12758.

Abstract

Background/aim: Small cell lung cancer (SCLC) is still a deadly type of cancer for which there are few effective therapeutic strategies. Development of a new molecule targeting agent is urgently desired. Previously we showed that recombination signal binding protein for immunoglobulin-kappa-J region (RBPJ) and mastermind-like 3 (MAML3) are new therapeutic targets for pancreatic cancer. In the present study, we analyzed whether RBPJ/MAML3 inhibition could also be a new therapeutic strategy for SCLC.

Materials and methods: Using silencing of RBPJ/MAML3, proliferation, invasion, migration and chemosensitivity of SBC-5 cells were investigated.

Results: RBPJ/MAML3 inhibition reduced Smoothened and HES1 expression, suggesting that RBPJ/MAML3 signaling was through Hedgehog and NOTCH pathways. In the analysis of cell functions, RBPJ/MAML3 inhibition significantly reduced proliferation and invasiveness via reduction of expression of matrix metalloproteinases. On the other hand, RBPJ/MAML3 inhibition also reduced chemosensitivity to cis-diamminedichlo-roplatinum and gemcitabine.

Conclusion: These results suggest that RBPJ and MAML3 could be new therapeutic targets for SCLC, however, chemosensitivity may be reduced in combinational use with other chemo-therapeutic agents.

Keywords: MAML3; RBPJ; SCLC; therapeutic target.

MeSH terms

  • Antineoplastic Combined Chemotherapy Protocols / pharmacology
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • DNA-Binding Proteins / metabolism*
  • Deoxycytidine / analogs & derivatives
  • Deoxycytidine / pharmacology
  • Gemcitabine
  • Hedgehog Proteins / metabolism
  • Humans
  • Immunoglobulin J Recombination Signal Sequence-Binding Protein / metabolism*
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / metabolism*
  • Matrix Metalloproteinases / metabolism
  • Neoplasm Invasiveness / pathology
  • Nuclear Proteins / metabolism*
  • Pancreatic Neoplasms / drug therapy
  • Pancreatic Neoplasms / metabolism
  • Receptors, Notch / metabolism
  • Signal Transduction / drug effects
  • Small Cell Lung Carcinoma / drug therapy
  • Small Cell Lung Carcinoma / metabolism*
  • Trans-Activators
  • Transcription Factors / metabolism*

Substances

  • DNA-Binding Proteins
  • Hedgehog Proteins
  • Immunoglobulin J Recombination Signal Sequence-Binding Protein
  • MAML3 protein, human
  • Nuclear Proteins
  • RBPJ protein, human
  • Receptors, Notch
  • Trans-Activators
  • Transcription Factors
  • Deoxycytidine
  • Matrix Metalloproteinases
  • Gemcitabine