The role of the parallel expression of the
KAI1 protein and
metalloproteinases (MMP-2 and MMP-9) in respect to the status of
steroid receptors in
endometrial cancer is still incompletely understood. The aim of this study was to evaluate the expression of and correlation between KAI1 on one hand and MMP-2 and MMP-9 on the other hand in terms of the status of the
estrogen (ER) and
progesterone receptors (PR) in 100 patients with
endometrial cancer. The expressions of KAI1, MMP-2, MMP-9, ER and PR were assessed immunohistochemically on
paraffin-embedded tissues. No correlations were found between these
biomarkers and the clinical and pathological parameters of the
endometrial cancer. However, in KAI1-positive cases, the expression was limited to a small area of
tumor tissue in FIGO stages III-IV. A tendency towards the high expression of MMP-9 and MMP-2 was observed in the advanced stages of
endometrial cancer (FIGO IIIA-IV). Positive correlations between the presence of KAI1 and PR and between the presence of MMP-9 and PR were found in
endometrial cancer. A positive correlation was also observed between KAI1 and MMP-2 expression, and a borderline one between KAI1 and MMP-9 expression in
endometrial cancer. KAI1+/PR+ and KAI1+/ER- immunophenotypes were observed more frequently in FIGO low stages and with well-differentiated
tumor grade. However, the KAI1-/ER+ and KAI1-/PR+ immunophenotypes were mainly observed in advanced stages of
endometrial cancer. KAI1+/
MMP-2+ and KAI1+/
MMP-9+ immunophenotypes were observed in FIGO Istage and with well-differentiated
tumors. KAI1-/
MMP-2+ and KAI1-/
MMP-9+ phenotypes were more often observed in FIGO stage II. Our study showed that
KAI1 protein, as well as
steroid receptors, might modulate MMP-2 and MMP-9 expression in
endometrial cancer. Our study revealed that the overlapping expression of the
biomarkers investigated here suggests that cooperation between these molecules exists, even at the early stages of
endometrial cancer growth, and may determine the speed of
tumor cell dissemination and might characterize the
biological behavior of
endometrial cancer.