Minor LLR of the anterior segments has the same rates of mortality and morbidity as OLR. However, the laparoscopic approach reduces blood loss and postoperative hospital stay.
We previously showed that disruptive complex I mutations in mitochondrial DNA are the main genetic hallmark of oncocytic tumors of the thyroid and kidney. We here report a high frequency of homoplasmic disruptive mutations in a large panel of oncocytic pituitary and head-and-neck tumors. The presence of such mutations implicates disassembly of respiratory complex I in vivo which in turn contributes to the inability of oncocytic tumors to stabilize HIF1alpha and to display pseudo-hypoxia. By utilizing transmitochondrial cytoplasmic hybrids (cybrids), we induced the shift to homoplasmy of a truncating mutation in the mitochondria-coded MTND1 gene. Such shift is associated with a profound metabolic impairment leading to the imbalance of alpha-ketoglutarate and succinate, the Krebs cycle metabolites which are the main responsible for HIF1alpha stabilization. We conclude that the main hallmarks of oncocytic transformation, namely the occurrence of homoplasmic disruptive mutations and complex I disassembly, may explain the benign nature of oncocytic neoplasms through lack of HIF1alpha stabilization.
This study demonstrated that CD-related histological lesions are always present in the bulb; sometimes this specific site is the only one affected. Therefore, we suggest taking 2 biopsies from the bulb and 2 from the distal duodenum for CD diagnosis.
Glioblastoma Multiforme (GBM) is an incurable malignancy. GBM patients have a short life expectancy despite aggressive therapeutic approaches based on surgical resection followed by adjuvant radiotherapy and concomitant chemotherapy. Glioblastoma growth is characterized by a high motility of tumour cells, their resistance to both chemo/radio-therapy, apoptosis inhibition leading to failure of conventional therapy. Cancer Stem Cells (CSCs), identified in GBM as well as in many other cancer types, express the membrane antigen prominin-1 (namely CD133). These cells and normal Neural Stem Cells (NSC) share surface markers and properties, i.e. are able to self-renew and differentiate into multiple cell types. Stem cell self-renewal depends on microenvironmental cues, including Extracellular Matrix (ECM) composition and cell types. Therefore, the role of microenvironment needs to be evaluated to clarify its importance in tumour initiation and progression through CSCs. The specific microenvironment of CSCs was found to mimic in part the vascular niche of normal stem cells. The targeting of GMB CSCs may represent a powerful treatment approach. Lastly, in GBM patients cancer-initiating cells contribute to the profound immune suppression that in turn correlated with CSCs STAT3 (CD133 + ). Further studies of microenvironment are needed to better understand the origin of GMB/GBM CSCs and its immunosuppressive properties.
Several molecular biomarkers have been suggested as predictors of outcome for pediatric ependymomas but deserve further validation in independent case series. We analyzed intracranial ependymomas belonging to a series of 60 patients prospectively treated according to the protocol sponsored by the Italian Association of Pediatric Hematology-Oncology. We used a tissue microarray to analyze nucleolin (NCL), cyclin-dependent kinase inhibitor 2A (CDKN2A), tumor protein 53 (TP53), and epidermal growth factor receptor (EGFR) by immunohistochemistry and by 1q gain by fluorescent in situ hybridization. The mRNA expression levels of EGFR, human telomerase reverse-transcriptase (HTERT), and Prominin 1 (PROM 1)/CD133 were evaluated by quantitative real-time PCR from cases with fresh-frozen tumor material available. Univariate and multivariate analyses of updated clinical data confirmed the prognostic significance of surgery (P < .01) and tumor grading (P < .05) for both relapse-free survival (RFS) and overall survival (OS). Among biomolecular markers, HTERT mRNA expression emerged with the strongest association with OS at multivariate analysis (hazard ratio [HR] = 9.9; P = .011); the 5-year OS was 84% versus 48% in the subgroups with HTERT median value <6 versus ≥ 6, respectively (P = .005). Five-year RFS was 46% versus 20% in the subgroups with low versus high NCL protein expression, respectively (P = .004), while multivariate Cox analyses gave suggestively high HRs for high versus low NCL (HR = 1.9; P = .090). The other genes tested were not significant at multivariate analyses, and genetic alterations of CDKN2A, TP53, EGFR, and HTERT loci were rare. The PROM1/CD133 cancer stem cell marker was strongly expressed at both RNA and protein levels in a substantial fraction of cases and was suggestively associated with a more indolent form of the disease. We conclude that NCL and HTERT represent the strongest prognostic biomarkers of RFS and OS, respectively, in our ependymoma case series.
BackgroundHigh-grade gliomas (HGGs) account for 15% of all pediatric brain tumors and are a leading cause of cancer-related mortality and morbidity. Pediatric HGGs (pHGGs) are histologically indistinguishable from their counterpart in adulthood. However, recent investigations indicate that differences occur at the molecular level, thus suggesting that the molecular path to gliomagenesis in childhood is distinct from that of adults. MicroRNAs (miRNAs) have been identified as key molecules in gene expression regulation, both in development and in cancer. miRNAs have been investigated in adult high-grade gliomas (aHGGs), but scant information is available for pHGGs.MethodsWe explored the differences in microRNAs between pHGG and aHGG, in both fresh-frozen and paraffin-embedded tissue, by high-throughput miRNA profiling. We also evaluated the biological effects of miR-17-92 cluster silencing on a pHGG cell line.ResultsComparison of miRNA expression patterns in formalin versus frozen specimens resulted in high correlation between both types of samples. The analysis of miRNA profiling revealed a specific microRNA pattern in pHGG with an overexpression and a proliferative role of the miR-17-92 cluster. Moreover, we highlighted a possible quenching function of miR-17-92 cluster on its target gene PTEN, together with an activation of tumorigenic signaling such as sonic hedgehog in pHGG.ConclusionsOur results suggest that microRNA profiling represents a tool to distinguishing pediatric from adult HGG and that miR-17-92 cluster sustains pHGG.
The optimal combination of bevacizumab with cytotoxic or cytostatic drugs in recurrent glioblastoma is unknown. We performed a phase 2 trial of combined bevacizumab and fotemustine for patients with glioblastoma at first relapse after radiotherapy and temozolomide. The primary endpoint was 6-month progression-free survival (PFS), while secondary endpoints were overall survival (OS), response rate based on RANO criteria and toxicity. Fifty-four patients with recurrent GBM were enrolled. The authors observed a 6-month PFS rate of 42.6 % (95 % CI 29.3–55.2) and a median PFS of 5.2 months (95 % CI 3.8–6.6). The median OS was 9.1 months (95 % CI 7.3–10.3). Twenty-eight patients (52 %) had a radiographic response, and a significant neurological improvement with steroid reduction was observed in 25/42 symptomatic patients (60 %). MGMT promoter methylation was significantly associated with improved PFS in univariate analysis. Most unifocal tumors at baseline had a focal enhancing progression (76 %), while the diffuse non-enhancing progression accounted for 9.5 %. Response or survival were not associated with any pattern of progression. Survival after failure of treatment was short. Twelve out of 54 patients (22 %) discontinued fotemustine for grade 3/4 myelotoxicity, while 4/54 (7.4 %) discontinued bevacizumab. This study failed to demonstrate a superiority of the combination of bevacizumab and fotemustine over either bevacizumab or fotemustine alone as historical controls. Future studies should explore alternative regimens of combination of the two drugs.
Summary Immunological markers improve specificity and accuracy of cell detection, therefore it is important to evaluate their usefulness in improving standard histological procedures.This study investigates whether immunocytochemical techniques increase the accuracy of detection, in axillary lymph nodes, of metastatic cells from infiltrating breast lobular carcinoma (ILC).Fifty cases of ILC reported to be node-negative were selected. New serial sections were cut from a total of 767 lymph nodes, stained with H&E and tested in immunoperoxidase (ABC procedure) with a conventional anti-Epithelial Membrane Antigen (EMA) serum, with a monoclonal raised against human milk fat globule membranes (HMFG-2) and with a monoclonal against 54kd keratin. Metastases were detected immunocytochemically in 12 cases (24%); in five of these cases metastatic cells were also visible in serial H&E sections. Monoclonals offered no evident advantage over anti-EMA conventional antiserum. Immunocytochemical positivity alone is not sufficient evidence for metastatic invasion since macrophages occasionally appear EMA-and HMFG-2-positive (probably because of secondary incorporation of the antigen), and so an improvement in the accuracy of breast cancer metastatic cell detection in axillary lymph nodes requires a combined histo-immunological approach.Prognosis and treatment of breast cancer is heavily influenced by the detection of metastases in lymph nodes. Foci formed by clumps of cells are easily spotted in standard histological sections, but a more difficult task is the detection of metastatic foci of one or few cells spread within a tissue.In as many as 24% of lymph nodes reported free of metastases by standard histological examination, various authors found metastases when multiple or serial sections were cut (Pickren, 1961;Fisher et al., 1978b). Immunological markers also improve the specificity and accuracy of cell detection, therefore it is important to evaluate their usefulness in improving standard histological procedures.Wells et al. (1984) utilizing 3 monoclonal antibodies found micro-metastatic foci in about 20% of lymph nodes from 45 cases of ductal or lobular breast cancer reported negative on conventional histology. On the contrary Sloane et al. (1980) reached the conclusion that detection of metastases in lymph nodes was not improved by immunocytochemistry. However they used a polyclonal antiserum against fat globule membranes of human milk.In this study 50 cases of infiltrating lobular carcinoma of the breast reported to have axillary lymph nodes free of metastases were re-examined to determine whether occult metastases were revealed
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