Mechanism of Intraperitoneal Spread of Free Cancer Cells

Peritoneal carcinomatosis (PC) from cancer cell dissemination from a primary tumor is considered a local cancer rather than systemic spread. Multiple primary cancers are responsible of peritoneal metastasis (PM). Patients affected by primary epithelial tumors plus PM can benefit from an aggressive surgical approach, such as the cytoreductive surgery (CRS), combined with hyperthermic intraperitoneal chemotherapy (HIPEC), which can result in long-term survival rates in selected patients [1]. Targeted indications are important for the success of these treatments. Patient selection is performed routinely depending on clinical parameters, preoperative tumor staging, and intraoperative findings. However, the origin mechanism of PM underlying specific biological aspects; in fact, some targeted molecules are responsible of tumor spread and peritoneal cancer cells adhesion. These molecular biomarkers are introduced in clinical practice to identify patients eligible for targeted therapies

Molecular karyotype and chromosomal localization of genes encoding ß-tubulin, cysteine proteinase, hsp 70 and actin in Trypanosoma rangeli

The molecular karyotype of nine Trypanosoma rangeli strains was analyzed by contour-clamped homogeneous electric field electrophoresis, followed by the chromosomal localization of ß-tubulin, cysteine proteinase, 70 kDa heat shock protein (hsp 70) and actin genes. The T. rangeli strains were isolated from either insects or mammals from El Salvador, Honduras, Venezuela, Colombia, Panama and southern Brazil. Also, T. cruzi CL-Brener clone was included for comparison. Despite the great similarity observed among strains from Brazil, the molecular karyotype of all T. rangeli strains analyzed revealed extensive chromosome polymorphism. In addition, it was possible to distinguish T. rangeli from T. cruzi by the chromosomal DNA electrophoresis pattern. The localization of ß-tubulin genes revealed differences among T. rangeli strains and confirmed the similarity between the isolates from Brazil. Hybridization assays using probes directed to the cysteine proteinase, hsp 70 and actin genes discriminated T. rangeli from T. cruzi, proving that these genes are useful molecular markers for the differential diagnosis between these two species. Numerical analysis based on the molecular karyotype data revealed a high degree of polymorphism among T. rangeli strains isolated from southern Brazil and strains isolated from Central and the northern South America. The T. cruzi reference strain was not clustered with any T. rangeli strain