Overcoming chemotherapy drug resistance by targeting inhibitors of apoptosis proteins (IAPs)

Rama Rathore, Jennifer E. McCallum, Elizabeth Varghese, Ana Maria Florea, Dietrich Busselberg

Research output: Contribution to journalReview article

70 Citations (Scopus)


Inhibitors of apoptosis (IAPs) are a family of proteins that play a significant role in the control of programmed cell death (PCD). PCD is essential to maintain healthy cell turnover within tissue but also to fight disease or infection. Uninhibited, IAPs can suppress apoptosis and promote cell cycle progression. Therefore, it is unsurprising that cancer cells demonstrate significantly elevated expression levels of IAPs, resulting in improved cell survival, enhanced tumor growth and subsequent metastasis. Therapies to target IAPs in cancer has garnered substantial scientific interest and as resistance to anti-cancer agents becomes more prevalent, targeting IAPs has become an increasingly attractive strategy to re-sensitize cancer cells to chemotherapies, antibody based-therapies and TRAIL therapy. Antagonism strategies to modulate the actions of XIAP, cIAP1/2 and survivin are the central focus of current research and this review highlights advances within this field with particular emphasis upon the development and specificity of second mitochondria-derived activator of caspase (SMAC) mimetics (synthetic analogs of endogenously expressed inhibitors of IAPs SMAC/DIABLO). While we highlight the potential of SMAC mimetics as effective single agent or combinatory therapies to treat cancer we also discuss the likely clinical implications of resistance to SMAC mimetic therapy, occasionally observed in cancer cell lines.

Original languageEnglish
Pages (from-to)898-919
Number of pages22
Issue number7
Publication statusPublished - 1 Jul 2017



  • Chemotherapy resistance
  • Combination therapy
  • Extrinsic apoptotic pathway
  • Inhibitors of apoptosis proteins
  • Intrinsic apoptotic pathway

ASJC Scopus subject areas

  • Pharmacology
  • Pharmaceutical Science
  • Clinical Biochemistry
  • Cell Biology
  • Biochemistry, medical
  • Cancer Research

Cite this