Immunotoxins, Resistance and Cancer Stem Cells: Future Perspective

Part of the Resistance to Targeted Anti-Cancer Therapeutics book series (RTACT, volume 6)


Cancer relapse or recurrence has been the greatest challenge in the treatment of this life threatening disease, which occurs due to resistance of cancer cells to drug or radiation therapy. Most often this resistance is developed during treatment, which makes it even more complicated, leading to the failure of chemo or radiation therapy in the majority of cases. To circumvent these problems associated with conventional therapies, newer strategies were adopted like targeted therapy using monoclonal antibodies, immunotoxins and antibody-drug conjugates. However, targeted therapy also showed failure in many in vitro and in vivo studies that was again attributed to the emergence of resistant cells. Here, we discuss the various factors and cellular mechanisms responsible for resistance against conventional therapies and targeted approaches like recombinant immunotoxins. Cancer stem cells (CSC’s) were identified as the major reason for resistance and their role in cancer relapse has been proved convincingly in recent studies. Hence, resistance mechanisms involved in CSC’s have been elaborated. We also summarize the strategies being adopted currently to overcome resistance and different means of targeting resistant cancer stem cells that could be used in the future.


Immunotoxins Cancer resistance Cancer stem cells Drug efflux Survival pathway Chemotherapy 



ATP-Binding Cassette


Acute myeloid leukemia


Breast cancer resistance protein


Bruton tyrosine kinase


Cancer stem cells


Damage-associated molecular patterns


Diphtheria toxin


Epithelial Mesenchymal transition


GlcCer synthase


Gemtuzumab ozogamicin


Gamma-secretase inhibitors


Hypoxia inducible factor




Mantle cell lymphoma


Multi Drug Resistance


Multidrug resistance protein 1


Oncolytic viruses




Small Cell Lung Cancer


Single cell network profiling


T cell acute lymphoblastic leukemia


Telomere maintenance mechanisms


Tumor necrosis factor alpha induced protein 3


TNF-related apoptosis-inducing ligand


Vascular endothelial growth factor



This research was supported in part by Department of Science and Technology and Department of Biotechnology, Government of India.


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© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Stem Cell and Molecular Biology laboratory, Department of BiotechnologyIndian Institute of Technology MadrasChennaiIndia

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