[Obesity and a risk of carcinoma]. / Obezita a riziko karcinómov.

At present, obesity and tumour diseases represent an important healthcare issue that has its socioeconomic and social dimensions. It has been known from literature for some time that certain types of tumours are more common in obese people than in people with normal body weight. About 3.2% of newly diagnosed cancers in men and 8.8% in women are associated with high body mass index (BMI). However, many studies suggest a more significant correlation between a waist-to-hip ratio (WHR) and a risk of cancer than a BMI. This is in line with the current orientation of knowledge not only to the quantity but mainly to the distribution of adipose tissue within a body with focus on metabolically active adipose tissue. Similarly, pathogenesis of cancers in obese patients is determined by a range of important mechanisms and metabolites such as insulin, insulin-like growth factors (IGFs), insulin resistance, inflammatory cytokines, adiponectin, leptin and many others. Despite this, many interconnections remain unknown. However, based on the results of many clinical and epidemiological studies we may argue that obesity is considered a risk factor of a number of tumour diseases such as prostate tumours, breast cancers in postmenopausal women, endometrial tumours, kidney or gastrointestinal tumours (stomach, oesophagus, colon).

Enrichment of rat oligodendrocyte progenitor cells by magnetic cell sorting.

The embryonic, neonatal, as well as adult rat spinal cords harbor a pool of neural stem cells (NSCs), which may be easily isolated and used to replace neuronal cell loss or remyelinate damaged axons following various neurodegenerative disorders. In the present study we have used magnetic cell sorting (MACs) technology to generate enriched oligodendroglial cell populations from the embryonic (E16) rat spinal cord. Target cells were separated by positive selection, using specific A2B5 antibody-labeled MicroBeads achieving optimal recovery and high purity of pro-oligodendroglial cells. Based on immunocytochemical analyses for oligodendroglial developmental markers (A2B5, NG2, RIP and MBP) we were able to characterize and quantify oligodendroglial progenitors (OPCs) and mature oligodendroglial cells in: (i) unseparated heterogeneous population of NSCs, or in (ii) antigen-antibody separated NSCs. Our results showed that MACs technology enable us to gain enriched OPCs from heterogeneous population of spinal NSCs, resulting in a 58-61% of mature oligodendrocytes content (MBP+, RIP+) in comparison to 6-12% of oligodendroglial cells acquired from unseparated population. In addition, the enriched OPCs could be cultured in vitro for several >8 passages, giving rise to a high number of newly formed spheres, as well as high expansion potential. These experiments indicate that MACs technology provide a feasible approach for experimental cell enrichment of desired oligodendroglial progeny, which may be used in future trials for cell-based therapies to treat spinal cord injury.