EXPRESSION OF OSTEOPONTIN AND OSTEONECTIN IN BREAST AND PROSTATE CANCER CELLS WITH DIFFERENT SENSITIVITY TO DOXORUBICIN

Osteonectin (SPARC) prognostic value in prostate cancer

BACKGROUND

Prostate cancer (PCa) is common malignancy among men worldwide. To date only few molecular markers are available to predict its course and outcome. SPARC is considered to be promising prognostic marker of PCa due to its involvement in various cancer processes.

MATERIALS AND METHODS

study was conducted on PCa surgical primary tumor samples, obtained from 84 patients. Level of SPARC mRNA expression was estimated using RT-qPCR. To identify SPARC protein (osteonectin) in prostate tissue, immunohistochemical analysis was conducted. Bioinformatical analysis was performed on UALCAN and TNMplot resources.

RESULTS

bioinformatical analysis demonstrated that SPARC mRNA levels are decreased in PCa samples, in comparison to normal tissue. In patients with lymph node metastases its levels are 1.26 times higher; p = 4.66E-02, than in N0 category. Ex vivo study demonstrated that SPARC expression was elevated on both mRNA and protein levels in PCa patients with lymph node metastases (by 2.34 and 1.91, respectively, p < 0.05). We established higher levels of SPARC mRNA and protein in PCa patients with T3 tumors, as well as high Gleason score. Estimation of survival rates demonstrated that PCa patients with a high level of SPARC mRNA and protein have decreased overall 2-year survival.

CONCLUSIONS

SPARC protein was overexpressed on mRNA and protein levels in patients with presence of lymph node metastases and higher Gleason score of tumors. Also, both mRNA and protein upregulation were associated with worse survival rates. The current study has therefore provided further evidence that SPARC is indeed linked to the prognosis and aggressiveness of human PCa.

SIGNIFICANCE OF OSTEOPONTIN FOR PREDICTING AGGRESSIVENESS OF PROSTATE CANCER

BACKGROUND

Effective prediction of the course of prostate cancer (PCa) and the stratification of treatment tactics largely depend on the use of prognostic markers that reflect the molecular and biological features of tumors. In view of the important role of matricellular proteins in the modulation of the growing tumor and metastasis of the hormone-dependent neoplasms, the aim of the work was to study the expression of osteopontin (OPN) at the protein and mRNA levels in the PCa tissue in order to assess the significance of this protein for predicting the aggressiveness of PCa.

MATERIALS AND METHODS

The work is based on the analysis of the results of the examination and treatment of 83 patients with PCa of stages II-IV. The study of OPN expression at the level of mRNA and protein in the PCa tissue was carried out using methods of the real time polymerase chain reaction and immunohistochemistry, respectively.

RESULTS

The OPN expression in the PCa tissue was 1.6 times (p < 0.05) higher in patients with regional lymph node metastases compared to patients without metastases. In patients with a Gleason score of < 7, the OPN expression in the tumor tissue was 1.4 times lower (p < 0.05) than in patients with poorly differentiated PCa. In patients with a high risk of tumor progression, the OPN expression level was 1.4 and 2.1 times higher (p < 0.05) compared to patients with a moderate and low risk of PCa progression. The patients with a high OPN expression level in the PCa tissue had significantly decreased 2-year recurrence-free survival rate (by 25%).

CONCLUSIONS

The obtained results indicate the expediency of using OPN expression indicators in the tumor tissue to predict the PCa aggressiveness and assess the risk of its recurrence.