Role of Tyrosine Kinases and their Inhibitors in Cancer Therapy: A Comprehensive Review.

BACKGROUND

Cancer has been recognized as one of the non-communicable diseases with an increasing number of new cases, higher morbidity, and higher mortality rates at the global level. Thus, there is non-stop search for novel targets and small molecules to improve the chemotherapeutic outcomes concerning potency, selectivity, efficiency, affinity, ADMET, etc. Among anticancer therapeutic targets, tyrosine kinase has been documented well and approved as an important target with the development of various clinically used drugs. There are several structurally diverse small molecules in different preclinical and clinical stages of development that act by affecting tyrosine kinases in cancerous cells. Here, we have summarized different potent molecules acting against tyrosine kinases that can be considered as anticancer agents.

OBJECTIVE

The current review focused on structural aspects of different chemical agents for inhibition of tyrosine kinases as anticancer agents.

METHODS

The present study provides a summarized review of published information on tyrosine kinase inhibitors, their binding pattern, potencies, and structure-activity relationships. The review also highlighted the structural aspects of the interaction between inhibitors and amino acid residues of tyrosine kinases. Moreover, it also provided a summary of different types of cancers and the currently available options for treatment.

RESULTS

Several studies are being conducted for the inhibition of different tyrosine kinases using small molecules for the treatment of cancer. Tyrosine kinases have been reported involving in routine cellular functions, growth, and division of cells through different pathways which depend on phosphorylation. The overexpression and uncontrolled activity of tyrosine kinases have been identified as an important feature of cancerous cells. Thus, various small molecules have been reported which inhibit tyrosine kinases to block the growth and division of cancer cells. Here, more than 30 highly potent inhibitors of tyrosine kinases are summarised, which consist of pyrimidine, pyrazole, triazine, quinazoline, quinoline, pyrazine, chromene, etc. rings as a basic skeleton with different substituents.

CONCLUSION

Inhibition of tyrosine kinases by different small molecules is an approved strategy for the development of novel anticancer agents. Several published reports have mentioned the characteristics of the different binding sites and crucial residues in tyrosine kinases for the design of novel molecular inhibitors. However, selectivity is an important criterion for the development of chemotherapeutic agents due to the existence of approximately 30 families of tyrosine kinases.