Volume 5 • Issue 4 • 1000159 Transl Med ISSN: 2161-1025 TM, an open access journal Sanyal et al., Transl Med (Sunnyvale) 2015, 5:4 DOI: 10.4172/2161-1025.1000159 Translational Medicine Research Article Open Access the COX-2 inhibitors mediated cancer cell killings. Tree COX-2 inhibitors used on comparable basis are 1) Celecoxib, a methylphenyl trifuoromethyl pyrazolyl benzene sulphonamide, 2) Etoricoxib, a chloromethyl methylsulfonyl phenyl bipyridine and 3) Diclofenac, a dichloro anilinophenyl acetic acid. Materials and Methods Chemicals 1, 2-Dimethylhydrazine (DMH) and Bradford reagent have been purchased from Sigma Aldrich (St. Louis, MO, USA). Celecoxib and Diclofenac were a generous gif from Ranbaxy Phamaceuticals (Gurgaon, India). Te primary antibody against Bcl-2, Bax, Bad, Apaf- 1, Cyt c, Caspase-9, Caspase-3, SK-1 and β-actin was purchased from Santa Cruz Biotechnology, Inc., CA (USA). Alkaline phosphatase conjugated secondary antibodies and BCIP-NBT were purchased from Genei, Bangalore, India. All other chemicals and reagents used in the present study were of analytical grade and purchased from the reputed Indian manufacturers. Animal Procurement Female Sprague-Dawley rats of body weight between 100-150g were obtained from the inbred population of the Central Animal House, Panjab University, Chandigarh. Te animals were acclimatized for at least 1 week and given normal diet (rodent chow) and water ad libitum. Tey were maintained as per the principles and guidelines of the Ethics Committee of Animal Care of Panjab University and in general, followed the NIH guidelines (Rule No. 23-85, as revised in 1985). Tey Abstract Bcl-2 family of proteins is implicated in the malignant tumors including colorectal cancer. Activation of Bcl-2 inhibits the pro-apoptotic proteins (Bax and Bad) and regulates many biological processes such as apoptosis, cell proliferation and cell growth. As the mitochondrial enzymes are involved in sphingolipid metabolism, it can regulate ceramide formation and in turn mitochondria play a central role for the regulation of ceramide induced apoptosis. Bcl-2/ Bcl- xL activates sphingosine kinases (SKs), resulting in the accumulation of S1P (sphingosine-1-phosphate), thereby reducing apoptosis. In the present study, the anti-neoplastic effects have been observed of Etoricoxib and Celecoxib, two COX-2 selective non-steroidal anti-infammatory drugs (NSAIDs), and Diclofenac, a preferential COX-2 inhibitory NSAIDs, in the early stage of colon cancer in rats. These NSAIDs regress the expressions of Bcl-2 and SK-1 and promote apoptosis. Gross morphological analysis revealed the occurrence of raised mucosal lesions called MPL or multiple plaque lesions, which were maximum in the 1, 2-Dimethylhydrazine (DMH) treated group and their number regressed with the co-administration of the NSAIDs. An abnormal histo-architecture like hyperplasia and dysplasia were evident in the carcinogenic group, which were reduced with NSAIDs co-administration. Activation of Mitochondrial Apoptosis and Regulation of Ceramide Signalling by COX-2 Inhibitors in Colon Cancer SN Sanyal * , Shelly Jain, Preety Ghanghas and Chandan Rana Department of Biophysics, Panjab University, Chandigarh, India 160014 *Corresponding author: Sanyal SN, Department of Biophysics, Panjab University, Chandigarh- 160014, India, Tel: +911722534122; E-mail: sanyalpu@gmail.com Received September 21, 2015; Accepted October 21, 2015; Published November 02, 2015 Citation: Sanyal SN, Jain S, Ghanghas P, Rana C (2015) Activation of Mitochondrial Apoptosis and Regulation of Ceramide Signalling by COX-2 Inhibitors in Colon Cancer. Transl Med 5: 159. doi:10.4172/2161-1025.1000159 Copyright: © 2015 Sanyal SN, et al., This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Keywords: Apoptosis; Bcl-2; Colorectal cancer; DMH; NSAIDs; SK-1 Introduction Cells die in response to various stimuli and during apoptosis or programmed cell death this happens in a controlled way to maintain homeostasis in constantly replicating tissues such as the colon [1]. Te pro-apoptotic Bax and Bad protein form important components of Bcl-2 family which is one of the dominant member in the mitochondrion form of apoptosis [2, 3]. It also involves down-modulation of Bax-antagonists such as Bcl-2 [4]. Translocation of pro-apoptotic Bax and Bak from the cytoplasm to the mitochondria is a crucial event in apoptosis cascades and therefore Bax has been recognized as an important mediator of anticancer drug-induced cell death [5]. Cytochrome c interacts with Apaf-1 and triggers the formation of apoptosome protein complex in the cytosol and in the presence of ATP and Apaf-1 then becomes an allosteric activator of the caspase cascade and the proteolytic demolition of the cell [6, 7]. Caspases are the family of endoproteases, it provides critical links in cellular regulatory networks to control infammation and cell death. Activation of apoptotic caspases results in either the inactivation or activation of the substrates, and the production of a cascade of signalling events permitting to the controlled demolition of cellular components [8]. Stimulation of infammatory caspases promotes the production of active pro-infammatory cytokines and promotes apoptosis. Caspases are critical links as their dysregulation underlies human diseases which includes infammatory disorders and cancer [9]. Cell signalling pathway mediated by ceramide has been shown to contribute to terminal cell diferentiation, cell cycle arrest and apoptosis [10] as well as to cell proliferation [11]. Ceramide may modify the relationship between pro-apoptotic (i.e., Bax and Bad) and anti-apoptotic (i.e., Bcl-2 and Bcl-XL) members of the Bcl-2 family of proteins. Key components of the sphingolipid metabolic pathway, are the ceramide and its metabolites, which includes sphingosine and sphingosine-1-phosphate (S1P). S1P has been exhibited to stimulate cell growth and prevent apoptosis [12]. Sphingosine kinase (SK) catalyse the phosphorylation of sphingosine that results in the synthesis of S1P. Sphingosine kinase (SK1) can be stimulated by a variety of growth factors, cytokines and mitogens [13]. Presently, in an experimental colorectal cancer (CRC) in rodents, apoptotic proteins and sphingosine kinase have been targeted in T r a n s l a ti o n a l M e d i c i n e ISSN: 2161-1025