[Study of the cytosolic concentrations of the tissue poly-peptide specific (TPS) antigen in infiltrating ductal carcinomas of the breast. Positive relationship with hormone dependency and negative with cellular proliferation]

Abstract

Introduction: The tissue-specific polypeptide antigen (TPS) is an epitope of the tissue polypeptide antigen (TPA) which is defined by the M3 monoclonal antibody and is related to cytokeratin 18. Several groups have demonstrated its value as a useful parameter in the follow-up of some tumors. This work has aimed to study the TPS cytosolic levels in infiltrating ductal carcinomas of the breast (IDC) and their possible correlations with other clinical-biological parameters.

Patients and methods: The TPS was determined by means of an immunoradiometric assay (Beki Diagnostics. Sweden). Other parameters included in the study were the estrogen receptors (ER), progesterone receptors (PR), pS2, cathepsin D, tissue-type plasminogen activator (t-PA), tumor size, axillary lymph node involvement, distant metastases, histological grade, ploidy and S-phase.

Results: The TPS cytosolic levels ranged from 1.8 to 606.3 KU/mg prt. (median 110.2) and had a significant correlation with the ER (r: 0.721), PR (r: 0.287), cathepsin D (r: 0.550) and t-PA (r:0.436). The TPS positive (> 110.2 KU/mg prt.) carcinomas had higher levels of ER (p: 0.001), PR (p: 0.021), pS2 (p: 0.058), cathepsin D (p: 0.000) and t-PA (p: 0.053) than the TPS negative tumors. When the IDC were classified according to S-phase values, we observed that the positive cases (S-phase > 8.1%, which represents the median value of all carcinomas) had lower levels of TPS (p: 0.046) than the negative tumors. Likewise, the GoG1 cellular fraction correlated positively and significantly with the TPS cytosolic levels (p: 0.000).

Conclusions: Based on our results, we suggest that there is a positive correlation between the TPS cytosolic levels and hormone-dependence parameters, as well as an inverse correlation between these and the cellular proliferation parameters. Based on the above, we consider that it is worthwhile to carry out further studies on cytosolic TPS in order to investigate its possible value as a prognostic parameter in breast carcinomas.