Metastasenresektion beim Prostatakarzinom

SPAG9 expression is increased in human prostate cancer and promotes cell motility, invasion and angiogenesis in vitro

Sperm-associated antigen 9 (SPAG9) is a recently characterized oncoprotein involved in the progression of several human malignancies. To elucidate the role of SPAG9 in the development of human prostate cancer (PCa), tissue microarray (TMA) and immunohistochemistry were used to detect the clinical relevance of SPAG9 in PCa tissues. We found that SPAG9 expression was increased in the PCa tissues when compared with the level in the tumor adjacent normal prostate tissues, and increased SPAG9 staining was significantly correlated with TNM stage and tumor grade. We also examined prostate cancer cell motility, invasion and angiogenesis ability following reduced SPAG9 expression by siRNA. Our data showed that knockdown of SPAG9 in prostate cancer cell lines inhibited cell motility and invasion due to the inactivation of metalloproteinase-2 (MMP‑2)/MMP-9 by upregulation of tissue inhibitor of metalloproteinase-1 (TIMP-1)/TIMP-2. Furthermore, downregulation of vascular endothelial growth factor (VEGF) secretion greatly contributed to the reduced ability of angiogenesis. Our data indicate that SPAG9 expression is significantly increased in PCa and it may be involved in the process of prostate cancer cell motility, migration and angiogenesis.

[Resecting hematogenous metastases: reasons against]

Urological malignancies represent approximately 40% of all solid tumors. Synchronous or metachronous organ metastases develop in 30% of patients. Depending on the tumor entity and tumor characteristics, resection of metastases can improve patient survival. Surgical resection of residual tumors is an integral part of the multimodal therapy concept of patients with nonseminomatous metastatic germ-cell cancer. Surgical inoperability is the only reason not to resect. Resection of hematogenous metastases from renal cell carcinoma has been postulated as a standard therapy for decades. Appropriate patient selection is the key for a survival benefit. Prognosticators such as patient's general condition as well as number, location, and size of metastases help to counsel and select patients accordingly. Metastases of transitional cell or penile carcinoma should only be resected when a response to systemic treatment is evident in the individual case. There is no evidence in favor of resecting organ-metastases of prostate cancer in the current guidelines and the literature. In this article, arguments against resection of metastases following the current literature and guidelines are described.

Role of RUNX3 in suppressing metastasis and angiogenesis of human prostate cancer

RUNX3 (runt-related transcription factor-3) has been reported to suppress tumor tumorigenesis and metastasis in different human cancers. In this study, we used tissue microarray (TMA) to determine the significance of RUNX3 in prostate cancer progession. Our results showed ectopic expression of RUNX3 in prostate cancer tissues when compared with tumor adjacent normal prostate tissues, and reduced RUNX3 staining was significantly correlated with TNM stage. Moreover, we demonstrated that RUNX3 overexpression inhibited prostate cancer cell migration and invasion resulting from the elevated upregulation of tissue inhibitor of matrix metalloproteinase-2 (TIMP-2), which subsequently inhibited metalloproteinase-2 (MMP-2) expression and activity in vitro. Knock down of RUNX3 expression broke up the balance of TIMP-2/MMP-2, whereas silence of TIMP-2 resulted in the inhibition of MMP-2 expression in prostate cells. We also showed that restoration of RUNX3 decreased vascular endothelial growth factor (VEGF) secretion and suppressed endothelial cell growth and tube formation. Strikingly, RUNX3 was demonstrated to inhibit tumor metastasis and angiogenesis in vivo. Altogether, our results support the tumor suppressive role of RUNX3 in human prostate cancer, and provide insights into development of targeted therapy for this disease.