Immunohistochemical and quantitative competitive PCR analyses of midkine and pleiotrophin expression in cervical cancer.

OBJECTIVE

The aim of this study was to determine midkine (MK) and pleiotrophin (PTN) expression in cervical cancer.

METHODS

Prospective study in tertiary teaching hospital. Normal and cancerous cervical tissues were obtained from healthy women (n = 19) and from patients with cervical cancer (n = 42). The expressions of MK and PTN mRNA and protein were examined by quantitative competitive PCR and by immunohistochemistry. MK and PTN mRNA and protein expressions were examined with respect to tumor stage and size.

RESULTS

The expressions of midkine and pleiotrophin mRNA in cervical cancer were higher than those in the normal cervix (MK, 175.59 +/- 63.3 vs 1.00 +/- 0.18 fmol, respectively; PTN, 3.18 +/- 1.25 vs. 0.86 +/- 0.12 fmol, respectively, P < 0.05), and their expressions were not correlated with cervical cancer stage or size of the tumor. The expressions of MK and PTN protein in cancerous tissue were higher than those in the normal cervix (P < 0.05). Moreover, the protein expression of MK, but not of PTN, correlated with tumor stage and size. The expressions of MK and PTN were not correlated with vascular density.

CONCLUSIONS

Our results suggest that increased midkine mRNA and protein expressions are associated with the carcinogenesis of cervical cancer.