Is chromosome radiosensitivity and apoptotic response to irradiation correlated with cancer susceptibility?

Purpose: Individuals who have been treated for breast cancer have been reported to have increased lymphocyte chromosomal sensitivity to ionizing radiation and a significantly lower apoptotic response to irradiation compared to controls. We set out to test these findings using a substantial number of cases sampled before treatment (which could alter the parameters measured), compared to age-matched controls with normal mammograms.

Material And Methods: We used the G2 chromosome breakage, and apoptotic response assays of peripheral blood lymphocytes to ionizing radiation to compare 211 unselected newly diagnosed and untreated breast cancer patients, with 170 age, sex and ethnically matched controls.

Reduction of TSG101 protein has a negative impact on tumor cell growth.

TSG101 was defined originally as a tumor-suppressor gene, raising the expectation that absence of the encoded protein should lead to increased tumor cell growth and, perhaps, increased tumor cell aggressiveness. We have used the RNA interference (RNAi) technique to downregulate TSG101 in PC3 (prostate cancer) and MDA-MB-231 (breast cancer) cells. An approximately 85% selective downregulation at the protein level was achieved in both cell lines over a period of 12 days as detected by Western blotting.

Site-directed perturbation of protein kinase C- integrin interaction blocks carcinoma cell chemotaxis.

Polarized cell movement is an essential requisite for cancer metastasis; thus, interference with the tumor cell motility machinery would significantly modify its metastatic behavior. Protein kinase C alpha (PKC alpha) has been implicated in the promotion of a migratory cell phenotype. We report that the phorbol ester-induced cell polarization and directional motility in breast carcinoma cells is determined by a 12-amino-acid motif (amino acids 313 to 325) within the PKC alpha V3 hinge domain.