Dialdehyd malonowy (MDA) w organizmie człowieka pochodzi z dwóch źródeł: spożywanego pokarmu i peroksydacji lipidów występujących w tkankach. Powstawanie MDA, a także wielkość i szybkość utleniania lipidów w tkankach organizmów żywych, zależy od wielu czynników endo- i egzogennych. Produkty peroksydacji lipidów, szczególnie MDA, wykazują właściwości cytotoksyczne, mutagenne i rakotwórcze. Mogą one również hamować enzymy związane z obroną komórki przed stresem oksydacyjnym. Mogą nie tylko przyczyniać się do rozwoju wielu chorób, ale stanowią również część procesu starzenia się. Organizm broni się w pewnym stopniu przed działaniem wolnych rodników, neutralizując je. Głównym źródłem przeciwutleniaczy jest żywność – produkty pochodzenia roślinnego. Styl życia, na który składają się dieta i aktywność fizyczna, jest ważnym elementem w zachowaniu zdrowia rozumianego jako dobre samopoczucie fizyczne i psychiczne. Nawyki żywieniowe i dieta bogata w przeciwutleniacze są modyfikowalnymi czynnikami, które nie tylko zapobiegają chorobom związanym z wiekiem, ale także opóźniają procesy starzenia.

Microsatellite instability (MSI) is a marker of the replication error phenotype. It is caused by impaired DNA mismatch repair processes (MMR), resulting in ineffectiveness of the mechanisms responsible for the DNA replication precision and postreplicative DNA repair. MSI underlies the pathogenesis of 10%–20% of colorectal cancer (CRC) cases. The data about the potential value of MMR status as a predictive factor for 5-fluorouracil (FU)-based chemotherapy remain unclear. According to National Comprehensive Cancer Network updated guidelines, MSI testing is recommended for all patients with stage II CRC because patients with MSI-H (high-frequency MSI) tumour may have a good prognosis and obtain no benefit from 5-FU-based adjuvant chemotherapy. The significance of the MSI status as a predictive factor for patients with metastatic disease was not confirmed. The association between the MSI status and the efficacy of the therapy based on anti-programmed death-1 receptor inhibitors requires further studies.

Oxidative stress may play an important role in colorectal cancer (CRC). The present study included 94 adult patients with CRC (52 men and 42 women) and 26 hospitalized patients (12 men and 14 women) in whom CRC was excluded (control group). During hospitalization, blood serum samples were collected from both groups. Apart from that, anthropometric measurements were taken and other clinical data were analyzed. Serum malondialdehyde (MDA) level, total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) were assayed. Subsequently, the relationship between the analyzed oxidative stress markers and selected clinical characteristics was investigated in both groups. The evaluation of oxidative stress marker values demonstrated that MDA and TAS levels were significantly higher in the control group than the CRC group (p < 0.001 and p = 0.019, respectively), while TOS levels were significantly higher in the CRC group than the control group (p = 0.005). Significantly lower OSI levels were found in the control group than in the CRC group (p < 0.001). Similar results can be observed when performing ROC analysis (receiver operating characteristic curve). Preliminary statistical analysis demonstrated that MDA levels in the study group depend on the location of the primary tumour (p = 0.035). Based on the post hoc Tukey test, a relationship was demonstrated between the MDA level and the left and right side of the colon (p = 0.040). The results may be evidence for a higher level of oxidative stress, including a compromised antioxidative defence system, in patients with CRC.

Some molds commonly occurring in the natural environment produce mycotoxins in the process of secondary metabolism. Aspergillus flavus and A. parasiticus are species of molds, which are responsible for the production of aflatoxins and are crucial in the pathogenesis of human diseases. Aspergillus species present in decaying plants, the soil and their spores are transferred via air currents and insects to crops and food storages. Aflatoxins B1, B2, G1, G2, M1 and M2 are the most common derivatives of aflatoxins. Ingestion of contaminated food is the main source of exposure to aflatoxins, which adversely affect the health of both humans and animals. The compounds can cause acute or chronic toxic effects of a teratogenic, mutagenic, carcinogenic, immunotoxic or hepatotoxic character. Molecular aflatoxins affect DNA mutations, postranslation peptids chains modification, proteins and nucleic acids methylation and the formation of free radicals.Due to aflatoxins carcinogenic features and frequent occurrence in food and forages they are routinely examinated in some groceries and agricultural products.

Introduction. The ability to form metastases which depends on the mechanisms of cell migration is an important element of the progression of cancer. In the present study we analyzed the genes involved in the regulation of migration in colon cancer cells. Materials and Methods. A total of 20 pairs of surgically removed tumoral and healthy (marginal) tissues samples from colorectal cancer patients at clinical stages I-II and III-IV were analyzed. The isolation of RNA from CRC and normal tissues and its subsequent molecular analysis were performed according to manufacturer’s instructions. Microarray data analysis was performed using the GeneSpring 11.5 platform and Significance Analysis of Microarrays (SAM). In SAM analysis to identify significantly differentially expressed genes score and -value parameters were used. Results. The largest increase in expression of genes was shown by MMP9, ADAM17, EphA2, and TIMP. Conclusions. Presented genes, especially ADAM17, MMP9, EphA2, TIMP1, ICAM 11, and CD4, may be used as prognostic markers of advanced stages of colorectal cancer, contributing to the development of new lines of therapy focused on reducing metastasis of the primary tumor. Introduction. The ability to form metastases which depends on the mechanisms of cell migration is an important element of the progression of cancer. In the present study we analyzed the genes involved in the regulation of migration in colon cancer cells. Materials and Methods. A total of 20 pairs of surgically removed tumoral and healthy (marginal) tissues samples from colorectal cancer patients at clinical stages I-II and III-IV were analyzed. The isolation of RNA from CRC and normal tissues and its subsequent molecular analysis were performed according to manufacturer’s instructions. Microarray data analysis was performed using the GeneSpring 11.5 platform and Significance Analysis of Microarrays (SAM). In SAM analysis to identify significantly differentially expressed genes score and -value parameters were used. Results. The largest increase in expression of genes was shown by MMP9, ADAM17, EphA2, and TIMP. Conclusions. Presented genes, especially ADAM17, MMP9, EphA2, TIMP1, ICAM 11, and CD4, may be used as prognostic markers of advanced stages of colorectal cancer, contributing to the development of new lines of therapy focused on reducing metastasis of the primary tumor.