The purpose of this study was to investigate whether Her-2/neu expression at diagnosis of osteosarcoma could provide biologic and prognostic information that predicts the risk of pulmonary metastases and outcome. Human epidermal growth factor (Her-2/neu) expression in 25 initial pretreatment osteosarcoma biopsies and 12 posttreatment pulmonary metastatic osteosarcoma resection specimens was assessed by standard immunohistochemical techniques on formalin-fixed paraffin-embedded tissue. As a screening analysis to determine if gene amplification may be a mechanism for increased Her-2/neu expression, FISH analysis was conducted on seven Her-2/neu immunostain-positive samples and five Her-2/neu immunostain-negative samples. Cytoplasmic Her-2/neu reactivity was identified in 11/25 (44%) of primary tumors and in 7/12 (58%) resection specimens from pulmonary metastases. Cytoplasmic Her-2/neu expression was associated with shorter overall metastasis-free survival. Her-2/neu gene amplification was identified by FISH analysis in six of the seven immunostain-positive samples but was also identified in two of the five immunostain-negative samples. Her-2/neu expression in patients with osteosarcoma is associated with an increased risk of metastasis and may define a subset of patients with a more aggressive tumor phenotype. Her-2/neu gene amplification may provide a mechanism for Her-2/neu overexpression in certain cases of osteosarcoma. Whether Her-2/neu expression influences outcome needs to be examined further in a prospective fashion. The hope is that Her-2/neu expression will identify patients who may benefit from the addition of directed biologic therapy.

Background Hypermethylation of CpG islands in the promoter regions of tumor suppressor genes is one mechanism of tumorigenesis. Caveolin‐1 (Cav‐1), a gene coding for the structural component of cellular caveolae, is involved in cell signaling and has been proposed to be a tumor suppressor gene in several malignancies. This gene maps to 7q31.1, a site known to be deleted in some prostate tumors. We chose to examine the methylation status of the promoter region of Cav‐1 to determine whether this gene could function as a tumor suppressor in prostate cancer Methods Genomic DNA from both tumor and normal prostate epithelial cells was obtained from paraffin‐embedded prostate sections by laser capture microdissection (LCM). The methylation status of 24 CpG sites at the 5′ promoter region of Cav‐1 was analyzed by bisulfite‐direct‐sequencing after amplification by PCR using primers specific for bisulfate modified DNA. Immunohistochemistry staining with a cav‐1‐specific antibody was also performed to evaluate the expression of the gene Results Twenty of the 22 (90.9%) informative cases showed promoter hypermethylation in the tumor cell population when compared with adjacent normal prostate cells with an average Methylation Index (potential frequency of total possible methylated Cs) from tumor cells equal to 0.426 vs. 0.186 for normal cells (P = 0.001). While no association with Gleason grade was found, overall increased methylation correlated with PSA failure (P = 0.016), suggestive of clinical recurrence. Elevated immunoreactivity with a Cav‐1 antibody was observed in tumor cells from 7 of 26 prostate samples tested; this was associated with a Gleason score but not correlated with PSA failure or Methylation Index Conclusions CpG sites at the 5′ promoter of Cav‐1 are more methylated in tumor than in adjacent normal prostate cells. Hypermethylation of the Cav‐1 promoter supports the notion that Cav‐1 may function as a tumor suppressor gene in prostate cancer and evidence is presented suggesting that methylation status of this gene is not only a marker for cancer but also may be predictive of outcome. Prostate 46:249–256, 2001. © 2001 Wiley‐Liss, Inc.

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Paternal duplications of chromosome region 11p15 can result in Beckwith-Weidemann syndrome (BWS), whereas maternal duplications of the same region on 11p15 can result in Russell-Silver syndrome (RSS). These two syndromes have numerous opposing phenotypes, especially with regards to growth parameters. The differences in the phenotype are proposed to be due to altered dosage of imprinted genes that control growth within this region of 11p15. Wolf-Hirschhorn syndrome (WHS) is due to deletions of a region in 4p16.3 and there is no known parent-of-origin effect for deletions of the WHS critical region, and no genes are known to be imprinted in this region. We report on three individuals with very similar unbalanced translocations resulting in a derivative chromosome 4 with both a deletion of 4p16.3 and a duplication of 11p15. Two of these individuals are family members with one inheriting the derivative 4 from her balanced mother and the other inheriting the derivative 4 from his balanced father. The third individual is unrelated and inherited his derivative 4 from his balanced father. While the findings of these individuals included some features of WHS and RSS or BWS, the phenotypes as an aggregate are distinct from these syndromes. The genomic and phenotypic characterization of these three individuals demonstrates how unbalanced translocations can result in the modification of chromosome duplication and deletion syndromes and identifies genomic architecture that may be responsible for mediating a recurrent translocation between 4p and 11p.