Cancer, rheumatoid arthritis, Alzheimer’s and Parkinson’s disease affect millions of people worldwide and responsible for
several deaths every year. This editorial is the collection of most of the known biochemical, cell organelles, receptors and
physiological mechanisms which are involved in pathophysiology of these diseases. The main aim of the article is to
summarize all possible drug targets which can either alter the signal transduction or indirect involvement in the management of
diseases. The physiological processes, receptors which are involved in signal transductions, biochemical/ biomolecules and cell
organelles may be good targets for cancer, rheumatoid arthritis, Alzheimer’s and Parkinsonism. Discussion to provide
knowledge about target selection for new drug discovery process is also presented. The properties of good drug target must
include modification in the treatment of the disease without a change in other physiological processes. The components of
signal transduction pathways are mainly the target of drugs which may easily alter. Cancer occurs mainly due to the mutation of
proteins sequencing DNA. This mutation is caused by various abnormal signal transduction mediated by Tie-2 kinase,
VEGFR2 (KDR) tyrosine kinase, epidermal growth factor receptor (EGFR), focal adhesion kinase (FAK), phosphatidylinositol
3-kinase (PI3K), mTOR, Hsp90, CDK, DHFR, histone deacetylase, carbonic anhydrases, Rad6B and p21-Activated kinase 4
(PAK-4) which are major targets associated to the cancer which have been extensively discussed by Kumar et al. [1-2] in this
thematic issue. Rheumatoid arthritis is due to the transcription gene alteration or altered gene expression which affects
metalloproteinase, cytokine production and proliferation/survival of cells. The main cause of Parkinson’s disease is degradation
of dopaminergic neurons, failure of ubiquitin protease system, mitochondrial dysfunction or oxidative distress. In cancer, the
AXL receptor kinase, phosphodiesterase, extracellular matrix metalloproteinase, Farnesyltransferase, arginyl tRNA synthase,
and lon protease may be the good choice of drug targets as biochemicals/biomolecules. In rheumatoid arthritis, mainly
sphingosine-1-phosphate, and interleukin-18 and in parkinson’s disease, α-synuclein, heat shock protein, RAGEs, uric acid,
parkin protein, transcription factor ED, mono amino oxidase and torsin-A may be the choice. Cell organelles like golgi matrix
protein, microtubules and generic DNA may be the preferred drug target for anticancer drugs while fibroblast, stromal and mast
cells in rheumatoid arthritis. For Parkinson’s disease epigenome, mitochondria may be the best choice for drug targets.
Angiogenesis, DNA synthesis, transcription regulator and some GI/S transitions like physiological process may be good targets
for anticancer drugs while apoptosis is considered for rheumatoid arthritis. As for as receptors are concerned the
cyclooxygenase 2, HSP2, protein kinase c for cancer and spleen/bruton tyrosine kinase may be better choices for rheumatoid
arthritis. For Parkinson’s disease, dopaminergic receptors, calcium channels, TIGARs, leucine rich receptor kinase-2, niacin
and signal receptors may be the good choice [2]. Bera discussed the major targets of Alzheimer’s disease which include
acetylcholinesterase, glycogen synthase kinase, muscarinic acetylcholine receptor, and N-methyl-D-aspartate receptor. Most
common neurodegenerative diseases are Alzheimer’s and Parkinson’s caused by both genetic and environmental factors.
Though various research strategies have been employed to eliminate the cause of the disease, but till date, successful strategies
available are symptomatic. Various compounds have been designed against the major neurodegenerative targets, such as
BACE1, acetylcholinesterase, glycogen synthase kinase, muscarinic acetylcholine receptor etc. in connection with Alzheimer’s
and Parkinson’s disorders [3].
