Anti-WT1 (C-terminal) polyclonal antibody

Zinc as an essential trace metal is a ubiquitous component of various molecules of the cell. Studies indicated that it may modulate functions of various cancer cell types, and can even inhibit metastasis formation in experimental models. In melanoma, zinc was shown to affect melanin production and to induce apoptosis. Using human melanoma cell lines, we have tested the effects of ZnSO4 on cell proliferation, survival, migration as well as in vivo on experimental liver colony formation. We have found that ZnSO4 has antiproliferative and proapoptotic effects in vitro. In SCID mice intraperitoneal administration of ZnSO4 specifically inhibited liver colony formation without affecting primary tumor growth. To reveal the molecular mechanisms of action of zinc in human melanoma, we have tested mRNA expression of zinc finger transcription factors and found a strong inhibitory effect on HIF1 alpha, as compared to WT1 whereas HIF2 alpha and MTF1 expression was unaffected. Immunohistochemical detection of HIF1 alpha protein in liver metastases confirmed its decreased nuclear expression after in vivo ZnSO4 treatment. These data indicate that in human melanoma zinc administration may have an antimetastatic effect due to a selective downregulation of HIF1 alpha.

Tubo-ovarian transitional cell carcinoma (TCC) is grouped with high-grade serous carcinoma (HGSC) in the current World Health Organization classification. TCC is associated with BRCA mutations and a better prognosis compared with HGSC. Previous papers examining the immunohistochemical features of TCC have studied limited numbers of samples. No marker reflecting the biological difference between TCC and HGSC is known. We collected a large cohort of TCC to determine whether TCC and HGSC could be distinguished by immunohistochemistry. A tissue microarray was built from 89 TCC and a control cohort of 232 conventional HGSC. Immunohistochemistry was performed, scored, and statistically analyzed for routine markers of HGSC and urothelial tumors: PAX8, WT1, p53, p16, ER, p63, and GATA3. Using scoring cutoffs commonly employed in clinical practice, the immunohistochemical profile of TCC was indistinguishable from HGSC for all markers. However, more detailed scoring criteria revealed statistically significant differences between the 2 groups of tumors with respect to ER, PAX8, and WT1. HGSC showed more diffuse and intense staining for PAX8 (P=0.004 and 0.001, respectively) and WT1 (P=0.002 and 0.002, respectively); conversely, TCC showed more intense staining for ER (P=0.007). TCC and HGSC therefore show subtle differences in their immunohistochemical profiles which might reflect underlying (epi)genetic differences. Further studies using proteomic analysis will focus on the identification of differentially expressed proteins that might serve as markers of TCC-like differentiation, which could help explain biologic differences between TCC and HGSC and might identify other cases of HGSC with a better prognosis.