Bortezomib induces caspase-dependent apoptosis in Hodgkin lymphoma cell lines and is associated with reduced c-FLIP expression: a gene expression profiling study with implications for potential combination therapies.

The Hodgkin cells and Reed-Sternberg cells (HRS) of classical Hodgkin lymphoma (CHL) are derived from germinal center B cells. The pathogenesis of CHL is unclear but constitutive activation of NFkappaB may contribute. Proteasome inhibition aimed at inhibiting NFkappaB has been shown to result in apoptosis in HRS cells. Here we investigated the effects of bortezomib, a proteasome inhibitor, in HRS cells with a combination of functional assays and gene expression profiling (GEP). Exposure of KMH2 and L428 cells to bortezomib resulted in inhibition of proliferation and induction of apoptosis. Gene expression analysis of KMH2 cells by oligonucleotide cDNA microarrays showed that a limited set of genes were differentially expressed involving several key cellular pathways including cell cycle and apoptosis. Among them, the caspase 8 inhibitor cFLIP was down-regulated and confirmed by Q-PCR. Given the evidence that cFLIP in HRS cells contribute to cells' insensitive to death receptor-mediated apoptosis, we combined bortezomib and TRAIL. This combination caused further down-regulation of cFLIP protein and increased apoptosis in CHL cells demonstrated by PARP p85 immunohistochemistry and immunoblotting. Such apoptotic effects were inhibited by caspase inhibitor z-VAD-FMK, confirming the pro-apoptotic effects of bortezomib and TRAIL are caspase-dependent. Bortezomib has no detectable effect on expression of TRAIL receptor DR4/DR5 in these two cell lines. Tissue microarray analysis of primary Hodgkin lymphomas displayed that 82% cases (95/116) expressed cFLIP in Reed-Sternberg cells. The discovery of apoptotic pathways that can be manipulated by proteasome inhibition provides rationale for the combination of bortezomib and agents such as TRAIL in CHL treatment.

Primary intravascular synovial sarcoma: a disease of young adult women? Report of a case diagnosed by aspiration biopsy and review of the literature.

Intravascular synovial sarcoma (IVSS) is an extremely rare tumor with only four well-documented cases in the English literature. All tumors were located in large veins of the lower extremities or trunk in young women except for one case occurring in a 54-yr-old woman. We report here an additional case of IVSS arising from the superior vena cava in a 32-yr-old woman who presented with a cervical mass and superior vena cava syndrome. A fine-needle aspiration biopsy (FNAB) was performed and showed a malignant biphasic tumor with spindle cell and epithelioid components. The tumor cells were negative for CD31, CD34, factor VIII, desmin, smooth muscle actin, and S-100 protein, and had positive staining for vimentin and cytokeratin (AE1/AE3) predominantly in the spindle and epithelial components, respectively. A diagnosis of synovial sarcoma was made and confirmed in a subsequent transvascular biopsy demonstrating chromosomal translocation t(X, 18) by fluorescence in situ hybridization using a dual color, break-apart-style probe for SYT. Although clinically similar to previously reported IVSS, this is the first case arising in large veins of the upper portion of the trunk and diagnosed by FNAB.

Comparison of morphologic and immunohistochemical features of cervical microglandular hyperplasia with low-grade mucinous adenocarcinoma of the endometrium.

Twenty cases of microglandular hyperplasia (MGH) of the uterine cervix and 14 cases of low-grade (nuclear) mucinous adenocarcinoma of the endometrium (MA) were compared morphologically and immunohistochemically. Subnuclear vacuoles were seen in 10 cases of MGH but were absent in all MA. Luminal squamous metaplasia was seen in only 10% of MGH cases versus 65% of MA cases. Stromal foam cells were present in 36% of MA but were absent in MGH cases. Both MGH and MA had minimal variation in nuclear size and inconspicuous nucleoli. As many as 8 mitoses/10 high-power fields (MF/10 HPF) were found in MA compared with 3 or fewer MF/10 HPF in MGH. Vimentin was expressed in 90% of MA but was absent in MGH. A significantly higher percentage of MA cells stained with MIB-1 than did those of MGH (mean 11% versus 0.5%). Both MA and MGH lacked CEA and p53 staining, whereas both had variable expression of ER and PR with no significant differences except that PR was absent in 40% of MGH cases. Our findings indicate that in the differential diagnosis of MGH versus MA, the presence of subnuclear vacuoles favors the former, whereas luminal squamous metaplasia, stromal foam cells, mitotic activity, vimentin expression, and MIB-1 expression favor the latter.