A proteomic approach for the identification of biomarkers in endometrial cancer uterine aspirate

Abstract

Endometrial cancer arises from the endometrium. It has a slow progression and a reported survival rate of 75%. The identification of soluble biomarkers in the uterine aspirate may be very useful for its early diagnosis. Uterine aspirates from 10 patients with endometrial cancer and 6 non-endometrial cancer controls were analyzed by two-dimensional gel electrophoresis coupled with mass spectrometry and western blotting for data verification. A total of 25 proteins with fold change in %V ≥2 or ≤0.5 in intensity were observed to change significantly (P<0.05). From the discovery phase, four proteins (costars family protein ABRACL, phosphoglycerate mutase 2, fibrinogen beta chain, annexin A3) were found to be present in the uterine aspirate of endometrial cancers and not in healthy aspirates. Western blotting verification data demonstrated that costars family protein ABRACL, phosphoglycerate mutase 2 were present only in endometrial cancer uterine aspirate while fibrinogen beta chain, annexin A3 were also present in healthy aspirates. To our knowledge, phosphoglycerate mutase 2 has not been previously associated with endometrial cancer. In this study we demonstrate that uterine aspirates are a promising biological fluid in which to identify endometrial cancer biomarkers. In our opinion proteins like costars family protein ABRACL and phosphoglycerate mutase 2 have a great potential to reach the clinical phase after a validation phase.

Diagnostic and prognostic relevance of microparticles in peripheral and uterine blood of patients with endometrial cancer

“…These endothelial microparticles (EMP) are vesicles formed by the endothelial cell membrane as a consequence of injury or activation. They are able to harbor cell surface proteins and cytoplasmic elements, thus expressing endothelial specific surface markers which reflect the parent cell status [11,12].…”

“…MPs are heterogeneous in shape, ranging in size from 0.1 to 1 um. MPs are composed of fragments of the parent cell, which comprise the plasma membrane proteins and cytoplasmic and nucleic constituents of the parent cell [11,12,13]. MPs are released into the systemic circulation, where they can effectively deliver their cargo with a long range to recipient cells.…”

Leiomyoma phosphoproteins involved in inhibition of oxidative stress and synthesis of reactive oxygen species

“…Phosphoprotein extracts (20 µg) from IMAc columns used for 2-DE were separated by 12% SDS-PAGE and then transferred to a nitrocellulose membrane. The western blotting procedure for phosphoproteins was conducted as previously described (18). The membrane was blocked with 5% BSA in TBS/0.05% Tween-20 (TBST) for 2 h at room temperature.…”

Proteomic Biomarkers for the Detection of Endometrial Cancer

“…This should be interpreted with caution given the small study size. Further verification by Western blot demonstrated the differential expression of only two proteins; costars family ABRACL and phosphoglycerate mutase 2 (PGAM2) [101]. Further studies are needed to validate both ABRACL and PGAM2 as EC diagnostic biomarkers prior to their clinical utility.…”