The addition of cooked chickpea seed (2% and 10%) to the daily diet is proposed as a chemopreventive agent against colon cancer.

Aflatoxin (AF) B1 is a main contaminant in diverse agricultural products. In an attempt to reduce this problem and the hazards to human health, an AFB1 inactivating system with ammonia has been developed. In this work we evaluated the efficiency of the system in mice using micronucleus (MN) and sister chromatid exchange (SCE) analysis. Four groups of animals were fed for 8 weeks with a special diet mainly composed of maize: (1) uncontaminated; (2) uncontaminated/inactivated; (3) contaminated/inactivated; and (4) contaminated. We evaluated MN at weekly intervals in peripheral blood, and in weeks 4 and 8 SCE frequencies were quantified in bone marrow cells. The results shows that animals fed with AFB1 contaminated/inactivated maize had a 45% lower level of induced cytogenetic damage than those animals fed with AFB1 contaminated but not inactivated maize. A residual amount of AFB1 after the inactivating treatment and reconversion back to AFB1 in the organism may account for the remaining increased levels of SCE and MN.

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In the scientific literature, it has been documented that electrochemical genosensors are novel analytical tools with proven clinical diagnostic potential for the identification of carcinogenic processes due to genetic and epigenetic alterations, as well as infectious diseases due to viruses or bacteria. In the present work, we describe the construction of an electrochemical genosensor for the identification of the k12p.1 mutation; it was based on use of Screen-Printed Gold Electrode (SPGE), Cyclic Voltammetry (CV), and Atomic Force Microscopy (AFM), for the monitoring the electron transfer trough the functionalized nanostructured surface and corresponding morphological changes. The sensitivity of the genosensor showed a linear response for the identification of the k12p.1 mutation of the K-ras gene in the concentration range of 10 fM to 1 μM with a detection limit of 7.96 fM in the presence of doxorubicin (Dox) as DNA intercalating agent and indicator of the hybridization reaction. Thus, the electrochemical genosensor developed could be useful for the identification of diseases related with the K-ras oncogene.

Introduction: Colon cancer diagnosis is usually performed late; so, it is necessary to search for prevention options. In vivo models are an option for the evaluation of chemopreventive agents, which are based mainly on the induction and promotion of carcinogenesis; however, they take a long time. This work aimed to evaluate and propose a carcinogenesis model, with tumor manifestation in a short time to prove the efficacy of chemopreventive compounds. Method: Colon carcinogenesis was induced in three groups (n = 7) male BALB/c mice with azoxymethane (AOM) and dextran sodium sulfate (DSS). The damage was assessed 14 weeks after the induction. Protocols were: 1) P1: two AOM injections and two DSS cycles at 1.5 % for five days, with three resting days between cycles; 2) P2: one AOM injection and two DSS cycles at 2 % for seven days with five rest days, and 3) P3: one AOM injection and two DSS cycles at 2 % for four days, with four resting days. Negative control was used in parallel, P0: with one injection of saline solution and water ad libitum. Weight, disease activity index (DAI), survival, tumor incidence, lipids, and protein oxidation were determined. Results: P2 showed greater severity in the assessed signs (100 % tumor incidence, colon weight/length ratio 101.68 ± 2.99 mg/cm), with low survival (43 %). P1 depicted lower mortality (14 %) and 83 % tumor incidence, without a significant difference to P2. P3 developed the disease but to a lesser degree (33 % tumor incidence). Furthermore, the three protocols showed lipid oxidation (0.4-0.58 ng/μg of protein) and proteins oxidation (0.6-1 ng/μg of protein). The P1 and P3 induction protocols presented less mortality, weight loss, and acceptable DAI, a weight/length ratio higher than the negative control and presence of tumors. Discussion: The use of AOM (10mg/kg) combined with DSS (1.5-2 %) are suitable models to evaluate the carcinogenic effect of compounds of interest, inflammation signs, lipids and proteins oxidation and a survival number adequate to perform the statistical analysis leading to accurate conclusions. Therefore, P1 and P3 are protocols that can be used in chemoprevention assays with satisfactory results.