Embryonal tumors with abundant neuropil and true Rosettes: A distinctive CNS primitive neuroectodermal tumor

Embryonal neoplasms of the central nervous system (CNS) generally arise in the early years of life and behave in a clinically aggressive manner, but vary somewhat in their microscopic appearance. Several groups have reported examples of an embryonal tumor with combined histologic features of ependymoblastoma and neuroblastoma, a lesion referred to as "embryonal tumor with abundant neuropil and true rosettes" (ETANTR). Herein, we present 22 new cases, and additional clinical follow-up on our 7 initially reported cases, to better define the histologic features and clinical behavior of this distinctive neoplasm. It affects infants and arises most often in cerebral cortex, the cerebellum and brainstem being less frequent sites. Unlike other embryonal tumors of the CNS, girls are more commonly affected than boys. On neuroimaging, the tumors appear as large, demarcated, solid masses featuring patchy or no contrast enhancement. Five of our cases (18%) were at least partly cystic. Distinctive microscopic features include a prominent background of mature neuropil punctuated by true rosettes formed of pseudo-stratified embryonal cells circumferentially disposed about a central lumen (true rosettes). Of the 25 cases with available follow-up, 19 patients have died, their median survival being 9 months. Performed on 2 cases, cytogenetic analysis revealed extra copies of chromosome 2 in both. We believe that the ETANTR represents a histologically distinctive form of CNS embryonal tumor. ©2009 by Lippincott Williams & Wilkins

Activated ERK1/2 expression in glioblastoma multiforme and in peritumor tissue

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Basal cell adenoma with S-100 positive stroma: a case report and literature review

Basal cell adenoma (BCA) of the salivary gland with presence of abundant S-100-positive stromal cells has been rarely reported. A case occurring in a 75-year-old man is presented here, as well as a review of the literature on the subject. The patient presented with a nodule in the right parotid gland. In addition to the typical features of BCA, histologically the resected tumor showed a substantial amount of stroma rich in S-100-positive spindle cells, a rarely reported finding in BCA. These cells were unreactive with a panel of myoepithelial markers, including calponin, p63, muscle-specific actin (MSA), smooth muscle actin (SMA), cytokeratin 14 (CK14), and glial fibrillary acidic protein (GFAP). Our results, in accordance with other reports, do not support a myoepithelial nature of these S-100-positive cells, and their precise nature remains elusive

Expression of the RNA-binding protein HuR and its clinical significance in human stage I and II lung adenocarcinoma

The ubiquitously expressed RNA-binding protein Hu antigen (HuR) participates in the post-transcriptional regulation of mRNAs bearing U- and AU-rich sequences. Expression of HuR is increased in cancers of the breast, colon, ovary and lung and cytoplasmic immunoreactivity for HuR was found to be closely related to poor outcomes in patients with these tumors. Since the regulation of HuR function is closely linked to its subcellular localization, we evaluated, by quantitative immunohistochemistry, the impact on clinical outcome of both nuclear and cytoplasmic levels (integrated density: ID) of HuR and of nuclear/ cytoplasmic ratio (N/C) in 54 lung adenocarcinomas from stage I and II patients. Nuclear and cytoplasmic Hur IDs and N/C were not associated with age, smoking or tumor diameter. Low N/C was significantly associated with lymph-node involvement at presentation. Cox’s regression analysis showed that high cytoplasmic, but not nuclear, HuR ID and low N/C were directly associated with the risk of death and metastasis. In the multivariate analysis, low HuR N/C retained an independent negative prognostic significance relative to the risk of metastasis and death. Moreover, the levels of N/C allowed us to discriminate subjects with the highest risk of metastasis and death among patients with lung adenocarcinomas expressing high levels of cytoplasmic HuR. In conclusion, the measure of the ratio between nuclear and cytoplasmic HuR levels allows a sensitive prognostic evaluation of the clinical outcome in early stage lung adenocarcinoma patient

Is CRX protein a useful marker in differential diagnosis of tumors of the pineal region?

The cone-rod homeobox (CRX) is a gene that belongs to the member of the orthodenticle homeobox (Otx) family, with important function in development and differentiation of retinal and pineal cells. Moreover, CRX appears to be specifically expressed in pineal tumors and retinoblastomas. We performed an immunohistochemical study on 91 pediatric and adult central nervous system tumors, plus 2 normal brain samples. Our results demonstrated that CRX is expressed not only in pineal parenchymal tumors and retinoblastoma, but also in a some medulloblastomas and supratentorial primitive neuroectodermal tumors. None of the glial tumors screened were positive for CRX. In conclusion, CRX could be useful in surgical neuropathology for the differential diagnosis of pineal region tumors, in particular to discriminate pineal tumors from glial tumors

Hu/elav RNA-binding protein HuR regulates parathyroid hormone related peptide expression in human lung adenocarcinoma cells

In 54 stage I and II human lung adenocarcinomas, HuR and PTHrP levels were positively correlated and the PTHrP-HuR status of the tumor was an independent prognostic marker of the clinical outcomes of patients. The possibility that HuR could upregulate PTHrP expression in lung adenocarcinoma was investigated by immunohistochemical, Western blot and RT-PCR analyses in HCC44 and DV90 human lung adenocarcinoma cell lines. In both cell lines, knockdown of HuR by specific siRNAs reduced PTHrP mRNAs and both cellular and secreted protein. Moreover, it inhibited cell growth and induced cell apoptosis, as revealed by the increase of caspase-3 activity. These effects were partially rescued by the addition of exogenous PTHrP (1-34). Analysis by actinomycin D assay revealed that in both cell lines HuR silencing produced a decrease of PTHrP mRNA half-life by about 70%. These findings add PTHrP to the list of lung cancer-associated genes, whose mRNA is stabilized by HuR