[Utility of chromosome banding with ALU I enzyme for identifying methylated areas in breast cancer].

Cancer is a group of disorders characterized by uncontrolled cell growth which is produced by two successive events: increased cell proliferation (tumor or neoplasia) and the invasive capacity of these cells (metastasis). DNA methylation is an epigenetic process which has been involved as an important pathogenic factor of cancer. DNA methylation participates in the regulation of gene expression, directly, by preventing the union of transcription factors, and indirectly, by promoting the "closed" structure of the chromatine.

[Clonal chromosomal anomalies in colorectal tumors].

Colorectal tumors constitute a reason of frequent consultation in gastroenterology services in the world. They constitute the second cause of mortality in the world and the fourth cause of mortality for cancer in Venezuela. It usually begins as a polyp that becomes malignant due to a mutation at the level of the genetic code that controls the growth and the repair of cells.