Preface

Chapter 6 **Approaches to Endow Ribonucleases with Antitumor Activity:**

**VI** Contents

Chapter 7 **Potential Anticancer Drugs Targeting Immune Pathways 169** Satyajit Das, Jaydip Biswas and Soumitra Kumar Choudhuri

**Lessons Learned from the Native Cytotoxic Ribonucleases 135** Jessica Castro, Marc Ribó, Antoni Benito and Maria Vilanova

> At a time when science is in constant progress and human life span is extended, we are still facing diseases for centuries present in the human species. Cancer is one of them, wide‐ spread and increasing. Although in recent years much progress in the field of prevention, diagnosis, and therapy of cancer has been made, the way to its complete eradication still seems long and hard.

> This book is arranged with the aim to summarize the recent findings in this field with the primary intention to offer the readers the most recent information on various therapeutic options and innovations. Hence, you can read here about natural products used to treat can‐ cer, new synthetic drugs, as well as how the very cell apparatus can be used to fight cancer. The chapters are written by scientists who dedicated years of their life to this research.

> Although this book is a drop in the sea, we hope that it contributes to the progress in the treatment of cancer and in such a way to a successful recovery of patients.

> > **Jasna Bankovic, MD, PhD** Associate Research Professor University of Belgrade Institute for Biological Research "Siniša Stanković" Belgrade, Serbia

**Anti-cancer Drugs from Natural Sources**

#### **Natural Products for Treatment of Chronic Myeloid Leukemia** Natural Products for Treatment of Chronic Myeloid Leukemia

Kalubai Vari Khajapeer and Rajasekaran Baskaran Kalubai Vari Khajapeer and Rajasekaran Baskaran

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/66175

## Abstract

Chronic myeloid leukemia (CML) is a hematological malignancy that arises due to reciprocal translocation of 3′ sequences from c-Abelson (abl) protooncogene on chromosome 9 with 5′ sequence of truncated break point cluster region (bcr) to chromosome 22. The fusion gene product BCR-ABL, a functional oncoprotein p210, is a constitutively activated tyrosine kinase that activates several cell proliferative signaling pathways. BCR-ABL-specific tyrosine kinase inhibitors (TKIs) such as imatinib, nilotinib and ponatinib potently inhibit CML progression. However, drug resistance owing to BCR-ABL mutations and overexpression is still an issue. Natural products are chemical compounds or substances produced by living organisms. They are becoming an important research area for cancer drug discovery due to their low toxicity and cost-effectiveness. Several lines of evidence show that many NPs such as alkaloids, flavonoids, terpenoids, polyketides, lignans and saponins inhibit CML cell proliferation and induce apoptosis. NPs not only differentiate CML cells into monocyte/erythroid lineage but also can reverse the multi-drug resistance (MDR) in CML cells. In this chapter, we review the anti-CML activity of various NPs.

Keywords: chronic myeloid leukemia (CML), BCR-ABL, TKIs, natural products (NPs), multi-drug resistance (MDR)
