Desmoplastic Small Round Cell Tumor of Major Salivary Glands: Report of 1 Case and a Review of the Literature

Desmoplastic small round cell tumor is a rare malignant neoplasm mostly occurring in the vicinity of or within the peritoneal cavity, and is uncommon in the head and neck region. Tumor location within a major salivary gland is exceptional. We report a case of a 41-year-old Chinese man with a history of diabetes mellitus and end-stage renal failure on peritoneal dialysis with a desmoplastic small round cell tumor occurring in the left submandibular gland. Fine-needle aspiration cytology showed variably cohesive clusters of small cells with hyperchromatic nuclei and fine granular chromatin. On histology the neoplasm displayed classic features of a desmoplastic small round cell tumor with angulated nests of small round blue cells in a fibromyxoid/desmoplastic stroma. Neoplastic cells were immunoreactive for cytokeratins (AE1/3), desmin (paranuclear dot-like), WT-1 (nuclear), epithelial membrane antigen, and CD56. EWS gene translocation and EWS-WT1 gene fusion were detected by fluorescence in situ hybridization and reverse transcriptase polymerase chain reaction, respectively. The case presented is the sixth case of and the oldest reported patient with a desmoplastic small round cell tumor occurring in a major salivary gland to date. Desmoplastic small round cell tumor should be considered in the differential diagnosis of a salivary gland neoplasm with a basaloid or small cell pattern on fine-needle aspiration cytology.

Sequence confirmation of the EWS-WT1 fusion gene transcript in the peritoneal effusion of a patient with desmoplastic small round cell tumor

Desmoplastic small round cell tumor (DSRCT) is a rare undifferentiated neoplasm. The prognosis is poor, even if therapy is instituted promptly. and thus it is important to differentiate it from other histologically and cytologically similar-looking malignancies of the young adult. We present a case of DSRCT in a 17-yr-old male with disseminated peritoneal disease and peritoneal effusion. The cytology sample showed a malignant small round cell tumor, the classical cytological features of DSRCT, and immunohistochemistry performed in the prepared cell block exhibited an antibody expression profile in keeping with DSRCT. Further material front the effusion was prepared for RNA extraction, following which a reverse-transcriptase polymerase chain reaction (RTPCR) and sequencing of the t(l l;22)(p13;q11 or q12) were carried out. The result showed the presence of the reciprocal translocation and thus confirmed the diagnosis of DSRCT. This case shows how molecular techniques (including sequencing) call be applied to cytology in clarifying and confirming certain difficult diagnosis of undifferentiated neoplasms, DSRCT in this particular case. Diagn. Cytopathol. 2003;29:341-343. (C) 2003 Wiley-Liss. Inc.

Epidermal growth factor receptor (EGFR), HER2 and insulin-like growth factor-1 receptor (IGF-1R) status in ovarian adult granulosa cell tumours

AIMS: Adult granulosa cell tumours (AGCTs) are uncommon ovarian sex cord-stromal tumours which recur following surgical removal in up to 50% of patients. Treatment options for recurrent and advanced stage AGCTs are limited, with poor response to chemotherapy and radiotherapy. We aimed to assess epidermal growth factor receptor (EGFR), HER2 and insulin-like growth factor-1 receptor (IGF-1R) status in AGCTs with a view to investigating whether or not these receptors might be potential therapeutic targets in these neoplasms.

METHODS AND RESULTS: Immunohistochemical staining for EGFR, HER2 and IGF-1R was undertaken in 31 AGCTs. Tumour DNA was also analysed for mutations in the tyrosine kinase domain of EGFR (exons 18-21) by Cobas mutation RT-PCR. Twenty-three of 31 (74%) AGCTs showed some degree of EGFR expression, generally with cytoplasmic or mixed membranous and cytoplasmic staining of variable intensity. Eleven of 27 (41%) cases exhibited strong membranous and cytoplasmic expression of IGF-1R. HER2 expression was not seen. No mutations were found in exons 18-21 of the EGFR gene in hot-spots of therapeutic relevance.

CONCLUSIONS: This study raises the possibility that anti-EGFR and/or anti-IGF-1R therapies may be of potential benefit in ovarian AGCTs, and this requires further study. Lack of known mutations within the tyrosine kinase domain of EGFR suggests that EGFR-related tyrosine kinase inhibitors may not be useful therapeutically.

Recombinant cathepsin S propeptide attenuates cell invasion by inhibition of cathepsin L-like proteases in tumor microenvironment

Human cathepsin L along with cathepsin S, K, and V are collectively known as cathepsin L-like proteases due to their high homology. The overexpression and aberrant activity of each of these proteases has been implicated in tumorigenesis. These proteases contain propeptide domains that can potently inhibit both their cognate protease and other proteases within the cathepsin L-like subfamily. In this investigation, we have produced the cathepsin S propeptide recombinantly and have shown that it is a potent inhibitor of the peptidolytic, elastinolytic, and gelatinolytic activities of the cathepsin L-like proteases. In addition, we show that this peptide is capable of significantly attenuating tumor cell invasion in a panel of human cancer cell lines. Furthermore, fusion of an IgG Fc-domain to the COOH terminus of the propeptide resulted in a chimeric protein with significantly enhanced ability to block tumor cell invasion. This Fc fusion protein exhibited enhanced stability in cell-based assays in comparison with the unmodified propeptide species. This approach for the combined inhibition of the cathepsin L-like proteases may prove useful for the further study in cancer and other conditions where their aberrant activity has been implicated. Furthermore, this strategy for simultaneous inhibition of multiple cysteine cathepsins may represent the basis for novel therapeutics to attenuate tumorigenesis.

Foxp3+ T cells induce Perforin-Dependent Dendritic Cell Death in Tumor-Draining Lymph Nodes.

Regulatory T (Treg) cells limit the onset of effective antitumor immunity, through yet-ill-defined mechanisms. We showed the rejection of established ovalbumin (OVA)-expressing MCA101 tumors required both the adoptive transfer of OVA-specific CD8(+) T cell receptor transgenic T cells (OTI) and the neutralization of Foxp3(+) T cells. In tumor-draining lymph nodes, Foxp3(+) T cell neutralization induced a marked arrest in the migration of OTI T cells, increased numbers of dendritic cells (DCs), and enhanced OTI T cell priming. Using an in vitro cytotoxic assay and two-photon live microscopy after adoptive transfer of DCs, we demonstrated that Foxp3(+) T cells induced the death of DCs in tumor-draining lymph nodes, but not in the absence of tumor. DC death correlated with Foxp3(+) T cell-DC contacts, and it was tumor-antigen and perforin dependent. We conclude that Foxp3(+) T cell-dependent DC death in tumor-draining lymph nodes limits the onset of CD8(+) T cell responses.

The Deubiquitinating Enzyme USP17 Is Highly Expressed in Tumor Biopsies, Is Cell Cycle Regulated, and Is Required for G1-S Progression

Ubiquitination is a reversible posttranslational modification that is essential for cell cycle control, and it is becoming increasingly clear that the removal of ubiquitin from proteins by deubiquitinating enzymes (DUB) is equally important. In this study, we have identified high levels of the DUB USP17 in several tumor-derived cell lines and primary lung, colon, esophagus, and cervix tumor biopsies. We also report that USP17 is tightly regulated during the cell cycle in all the cells examined, being abundantly evident in G1 and absent in S phase. Moreover, regulated USP17 expression was necessary for cell cycle progression because its depletion significantly impaired G1-S transition and blocked cell proliferation. Previously, we have shown that USP17 regulates the intracellular translocation and activation of the GTPase Ras by controlling Ras-converting enzyme 1 (RCE1) activation. RCE1 also regulates the processing of other proteins with a CAAX motif, including Rho family GTPases. We now show that USP17 depletion blocks Ras and RhoA localization and activation. Moreover, our results confirm that USP17-depleted cells have constitutively elevated levels of the cyclin-dependent kinase inhibitors p21cip1 and p27kip1, known downstream targets of Ras and RhoA signaling. These observations clearly show that USP17 is tightly regulated during cell division and that its expression is necessary to coordinate cell cycle progression, and thus, it may be considered a promising novel cancer therapeutic target. Cancer Res; 70(8); 3329–39. ©2010 AACR.

Cancer-related ectopic expression of the bone-related transcription factor RUNX2 in non-osseous metastatic tumor cells is linked to cell proliferation and motility

Introduction: Metastatic breast cancer cells frequently and ectopically express the transcription factor RUNX2, which normally attenuates proliferation and promotes maturation of osteoblasts. RUNX2 expression is inversely regulated with respect to cell growth in osteoblasts and deregulated in osteosarcoma cells.

The tumor suppressor gene DLEC1 is frequently silenced by DNA methylation in hepatocellular carcinoma and induces G1 arrest in cell cycle

Background/Aims: The chromosome locus 3p21.3 is a

Gelsolin induces colorectal tumor cell invasion via modulation of the urokinase-type plasminogen activator cascade

Gelsolin is a cytoskeletal protein which participates in actin filament dynamics and promotes cell motility and plasticity. Although initially regarded as a tumor suppressor, gelsolin expression in certain tumors correlates with poor prognosis and therapy-resistance. In vitro, gelsolin has anti-apoptotic and pro-migratory functions and is critical for invasion of some types of tumor cells. We found that gelsolin was highly expressed at tumor borders infiltrating into adjacent liver tissues, as examined by immunohistochemistry. Although gelsolin contributes to lamellipodia formation in migrating cells, the mechanisms by which it induces tumor invasion are unclear. Gelsolin's influence on the invasive activity of colorectal cancer cells was investigated using overexpression and small interfering RNA knockdown. We show that gelsolin is required for invasion of colorectal cancer cells through matrigel. Microarray analysis and quantitative PCR indicate that gelsolin overexpression induces the upregulation of invasion-promoting genes in colorectal cancer cells, including the matrix-degrading urokinase-type plasminogen activator (uPA). Conversely, gelsolin knockdown reduces uPA levels, as well as uPA secretion. The enhanced invasiveness of gelsolin-overexpressing cells was attenuated by treatment with function-blocking antibodies to either uPA or its receptor uPAR, indicating that uPA/uPAR activity is crucial for gelsolin-dependent invasion. In summary, our data reveals novel functions of gelsolin in colorectal tumor cell invasion through its modulation of the uPA/uPAR cascade, with potentially important roles in colorectal tumor dissemination to metastatic sites.

Macrophages Control Vascular Stem/Progenitor Cell Plasticity Through Tumor Necrosis Factor-α-Mediated Nuclear Factor-κB Activation

Objective: Vascular lineage differentiation of stem/progenitor cells can contribute to both tissue repair and exacerbation of vascular diseases such as in vein grafts. The role of macrophages in controlling vascular progenitor differentiation is largely unknown and may play an important role in graft development. This study aims to identify the role of macrophages in vascular stem/progenitor cell differentiation and thereafter elucidate the mechanisms that are involved in the macrophage- mediated process.

Approach and Results: We provide in vitro evidence that macrophages can induce endothelial cell (EC) differentiation of the stem/progenitor cells while simultaneously inhibiting their smooth muscle cell differentiation. Mechanistically, both effects were mediated by macrophage-derived tumor necrosis factor-α (TNF-α) via TNF-α receptor 1 and canonical nuclear factor-κB activation. Although the overexpression of p65 enhanced EC (or attenuated smooth muscle cell) differentiation, p65 or TNF-α receptor 1 knockdown using lentiviral short hairpin RNA inhibited EC (or rescued smooth muscle cell) differentiation in response to TNF-α. Furthermore, TNF-α–mediated EC differentiation was driven by direct binding of nuclear factor-κB (p65) to specific VE-cadherin promoter sequences. Subsequent experiments using an ex vivo decellularized vessel scaffold confirmed an increase in the number of ECs and reduction in smooth muscle cell marker expression in the presence of TNF-α. The lack of TNF-α in a knockout mouse model of vein graft decreased endothelialization and significantly increased thrombosis formation.

Conclusions: Our study highlights the role of macrophages in directing vascular stem/progenitor cell lineage commitment through TNF-α–mediated TNF-α receptor 1 and nuclear factor-κB activation that is likely required for endothelial repair in vascular diseases such as vein graft.

The BTA stat test:A tumor marker for the detection of upper tract transitional cell carcinoma

Objectives. To conduct a prospective evaluation to determine the utility of the BTA stat test in the detection of upper tract transitional cell carcinoma (UTTCC). Monitoring for UTTCC currently relies on invasive procedures such as upper tract imaging, ureteral washing cytology (UWC) and/or ureteroscopy, or voided urine cytology (VUC). The BTA stat test is a sensitive qualitative immunoassay that detects human complement factor H-related protein in voided urine.

Methods. A total of 81 patients participated, 27 with histopathologically confirmed UTTCC, 26 with upper tract calculi, and 28 with microscopic hematuria but no evidence of urologic disease. Voided specimens collected before surgery or treatment were tested with the BTA stat test and VUC. UWC was performed in specimens collected by a ureteral catheter.

Results. The BTA stat test was significantly more sensitive and specific than VUC or UWC. The overall sensitivity for each was 82%, 11%, and 48%; the specificity was 89%, 54%, and 33%. The positive predictive value for the BTA stat test was 79% and the negative predictive value was 91%, both the highest of the three tests.

Conclusions. The BTA stat test was superior to VUC and UWC in the detection of UTTCC. These results may support the adoption of a less aggressive follow-up policy when monitoring for UTTCC when the BTA stat result is negative. If cystoscopy is negative and the BTA stat test is positive, upper tract investigations should be expedited and, if the bladder is in place, bladder biopsies performed. (C) 2001, Elsevier Science Inc.

Time and Cell Type Dependency of Survival Responses in Co-cultured Tumor and Fibroblast Cells after Exposure to Modulated Radiation Fields

Advanced radiotherapy techniques such as intensity-modulated radiation therapy (IMRT) achieve high levels of conformity to the target volume through the sequential delivery of highly spatially and temporally modulated radiation fields, which have been shown to impact radiobiological response. This study aimed to characterize the time and cell type dependency of survival responses to modulated fields using single cell type (SCT) and mixed cell type (MCT) co-culture models of transformed fibroblast (AG0-1522b) cells, and prostate (DU-145) and lung (H460) cancer cells. In SCT cultures, in-field responses showed no significant time dependency while out-of-field responses occurred early, and plateaued 6 h after irradiation in both DU-145 and H460 cells. Under modulated beam configurations MCT co-cultures showed cell-specific, differential out-of-field responses depending on the irradiated in-field and responding out-of-field cell type. The observed differential out-of-field responses may be due to the genetic background of the cells, in particular p53 status, which has been shown to mediate radiation-induced bystander effects (RIBEs). These data provide further insight into the radiobiological parameters that influence out-of-field responses, which have potential implications for advanced radiotherapy modalities and may provide opportunities for biophysical optimization in radiotherapy treatment planning.