Repositioning of simvastatin for diabetic colon cancer: role of CDK4 inhibition and apoptosis

There is increased risk of colon cancer in both men and women having diabetes. The objective of the study was to evaluate the role of simvastatin in colon cancer associated with type 2 diabetes mellitus. Diabetes was induced by administering high fat diet with low dose streptozotocin model. 1,2 dimethylhydrazine (25 mg/kg, sc) was used for colon cancer induction. MTT assay, scratch assay, clonogenic assay and annexin V-FITC assay using flow cytometry were performed on HCT-15 cell line. Simvastatin controlled diabetes and colon cancer in animal models and reduced mRNA expression of CDK4 in colon tissues. In vitro studies revealed that simvastatin showed a decrease in cell viability and produced dose dependent decrease in clone formation. There was decrease in the rate of migration with increase in concentration of simvastatin in scratch assay. Moreover, simvastatin induced apoptosis as depicted from annexin V-FITC assay using flow cytometry as well as that revealed by tunnel assay. Our data suggest that simvastatin exhibits protective role in colon cancer associated with diabetes mellitus and acts possibly via down regulation of CDK4 and induction of apoptosis and hence can be considered for repositioning in diabetic colon cancer.

Probing the chemoprevention potential of the antidepressant fluoxetine combined with epigallocatechin gallate or kaempferol in rats with induced early stage colon carcinogenesis

The enhanced chemopreventive action against 1,2 Dimethylhydrazine (DMH)-induced preneoplastic lesion in rats could be achieved via simultaneous administration of the antidepressant fluoxetine (FLX) with two natural polyphenolic compounds viz., kaempferol (KMP) and/or epigallocatechin-gallate (EGCG). The obtained results revealed that single FLX pre-treatment possess a significant apoptotic effect by increasing the activity of serum and colon tissue caspase 3. It also attenuated the DMH driven increase in, colon tissue MDA, NO, PCNA and COX-2 expression as well as serum and colon tissue β-catenin, with a decrease in the multiplicity of ACF and number of MPLs. The combination of FLX with either KMP or EGCG improved the antioxidant, anti-inflammatory and antiproliferating activities but with higher apoptotic activity in case of KMP. Eventually, histopathological assessment of colon tissues exposed that while sole pre-treatment can improve DMH-induced hyperplasia with only moderate inflammatory infiltration, tissues from the combined pre-treatment regimens groups exhibited almost a normal colonic architecture with slight submucosal edema. The study proved that single FLX administration prior to DMH exerts a chemopreventive effect and that the investigated combined pre-treatment regimens demonstrated more potent chemopreventive and antiproliferative actions.

Ethyl acetate fraction of Muntingia calabura L. exerts anti-colorectal cancer potential via regulating apoptotic and inflammatory pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Muntingia calabura L. is a plant with traditional pharmacological relevance. The various plant parts are used by tribal communities for treating gastric ulcers, prostate gland swellings, headache, cold etc. Hence, an attempt was made to evaluate the anti-colorectal cancer potential of ethyl acetate fraction of M. calabura (EFMC).

MATERIALS AND METHODS

HR LC-MS analysis was carried out for the identification of compounds present in EFMC. 1,2 Dimethylhydrazine (DMH) induced animal model was used for the evaluation of anti-CRC potential of EFMC. Antioxidant enzyme status, oxidative stress marker status, hepatic and renal function marker level were determined. Evaluation of mRNA level expression of inflammatory and apoptotic genes, hematological and histopathological examinations were also carried out to figure out the extent of colorectal cancer (CRC) and the beneficial role offered by EFMC.

RESULTS

HR LC-MS analysis of EFMC revealed the presence of ten pharmacologically active compounds. EFMC treatment made the altered levels of antioxidant enzymes, oxidative stress markers, liver and renal function markers to retain near to its normal range. The hematological and histopathological evaluations also confirmed the anti-CRC effects exhibited by EFMC. EFMC offered a regulatory control over the inflammatory and apoptotic genes thereby mitigating the damaging effects of CRC.

CONCLUSION

The present study depicted the presence of therapeutically active compounds exhibiting strong antioxidant, anti-inflammatory and anticancer potential. The beneficial role offered by these compounds could be responsible for the amelioration of DMH induced CRC. Hence, EFMC can be used as an anti-CRC agent in human subjects.