213 research outputs found
Frequent detection of human polyomavirus 6 in keratoacanthomas
BACKGROUND: The recent discovery of the Merkel cell polyomavirus and its consistent association with Merkel cell carcinoma has drawn attention to the numerous recently discovered polyomaviruses and their possible involvement in the etiopathogenesis of non-melanoma skin cancer (NMSC). Data on the recently discovered human polyomavirus 6 (HPyV6) and its role in NMSC are sparse and in part controversial. METHODS: In the present study we tested a large number (n = 299) of NMSC specimens for the presence of human polyomavirus 6 (HPyV6) by DNA PCR and HPyV6 fluorescence in situ hybridization (FISH). In detail, 59 keratoacanthomas (KA), 109 basal cell carcinomas (BCC), 86 squamous cell carcinomas (SCC) and 45 trichoblastomas (TB) were tested for the presence of HPyV6. RESULTS: HPyV6 DNA PCR and subsequent sequence analysis revealed that 25 KAs (42.3 %), 23 BCCs (21.1 %), 8 SCCs (9.3 %) and 10 TBs (22.2 %) were HPyV6 positive. The presence of HPyV6 DNA was visualized and validated on the single cell level within the histomorphological context by HPyV6 fluorescence in situ hybridization. CONCLUSIONS: The high frequency of HPyV6 DNA in 42.3 % of KA possibly points to a role for HPyV6 in the etiopathogenesis of KAs. Although the detection rate of HPyV6 DNA in BCCs and TBs is within the previously reported detection range in normal skin, it does not exclude a possible role for HPyV6 in the carcinogenesis in a significant subset of these skin tumors
Large cell neuroendocrine carcinoma with a solitary brain metastasis and low Ki-67:a unique subtype
INTRODUCTION: Stage IV large cell neuroendocrine carcinoma (LCNEC) of the lung generally presents as disseminated and aggressive disease with a Ki-67 proliferation index (PI) 40-80%. LCNEC can be subdivided in two main subtypes: the first harboring TP53/RB1 mutations (small cell lung carcinoma (SCLC)-like), the second with mutations in TP53 and STK11/KEAP1 (non-small cell lung carcinoma (NSCLC)-like). Here we evaluated 11 LCNEC patients with only a solitary brain metastasis and evaluate phenotype, genotype and follow-up. METHODS: Eleven LCNEC patients with solitary brain metastases were analyzed. Clinical characteristics and survival data were retrieved from medical records. Pathological analysis included histomorphological analysis, immunohistochemistry (pRB and Ki-67 PI) and next generation sequencing (TP53, RB1, STK11, KEAP1 and MEN1). RESULTS: All patients had N0 or N1 disease. Median overall survival (OS) was 12 months (95% confidence interval (CI) 5.5-18.5 months). Mean Ki-67 PI was 59% (range 15-100%). In 6/11 LCNEC Ki-67 PI was ≤40%. OS was longer for Ki-67 ≤40% compared to >40% (17 months (95% CI 11-23 months) vs. 5 months (95% CI 0.7-9 months), p=0.007). Two patients were still alive at follow-up after 86 and 103 months, both had Ki-67 ≤40%. 8/11 patients could be subclassified and both SCLC-like (n=6) and NSCLC-like (n=2) subtype were present. No MEN1 mutation was found. CONCLUSION: Stage IV LCNEC with a solitary brain metastasis and N0/N1 disease show in the majority of cases Ki-67 PI ≤40% and prolonged survival, distinguishing them from general LCNEC. This unique subgroup can be both of the SCLC-like and NSCLC-like subtype
Differential loss of chromosome 11q in familial and sporadic parasympathetic paragangliomas detected by comparative genomic hybridization
Parasympathetic paragangliomas (PGLs) represent neuroendocrine tumors
arising from chief cells in branchiomeric and intravagal paraganglia,
which share several histological features with their sympathetic
counterpart sympathoadrenal paragangliomas. In recent years, genetic
analyses of the familial form of PGL have attracted considerable interest.
However, the majority of paragangliomas occurs sporadically and it remains
to be determined whether the pathogenesis of sporadic paraganglioma
resembles that of the familial form. Furthermore, data on comparative
genetic aberrations are scarce. To provide fundamental cytogenetic data on
sporadic and hereditary PGLs, we performed comparative genomic
hybridization using directly fluorochrome-conjugated DNA extracted from 12
frozen and 4 paraffin-embedded tumors. The comparative genomic
hybridization data were extended by loss of heterozygosity analysis of
chromosome 11q. DNA copy number changes were found in 10 (63%) of 16
tumors. The most frequent chromosomal imbalance involved loss of
chromosome 11. Six of seven familial tumors and two of nine sporadic
tumors showed loss of 11q (86% versus 22%, P = 0.012). Deletions of 11p
and 5p were found in two of nine sporadic tumors. We conclude that overall
DNA copy number changes are infrequent in PGLs compared to sympathetic
paragangliomas and that loss of chromosome 11 may be an important event in
their tumorigenesis, particularly in familial paragangliomas
MEN1 Gene mutation and reduced expression are associated with poor prognosis in pulmonary carcinoids
Context: MEN1 gene alterations have been implicated in lung carcinoids, but their effect on gene expression and disease outcome is unknown.
Objective: Our objective was to analyze MEN1 gene and expression anomalies in lung neuroendocrine neoplasms and their correlations with clinicopathologic data and disease outcome.
Design: We examined 74 lung neuroendocrine neoplasms including 58 carcinoids and 16 high-grade neuroendocrine carcinomas (HGNECs) for MEN1 mutations (n = 70) and allelic losses (n = 69), promoter hypermethylation (n = 65), and mRNA (n = 74) expression. Results were correlated with disease outcome.
Results: MEN1 mutations were found in 7 of 55 (13%) carcinoids and in 1 HGNEC, mostly associated with loss of the second allele. MEN1 decreased expression levels correlated with the presence of mutations (P = .0060) and was also lower in HGNECs than carcinoids (P = .0024). MEN1 methylation was not associated with mRNA expression levels. Patients with carcinoids harboring MEN1 mutation and loss had shorter overall survival (P = .039 and P = .035, respectively) and low MEN1 mRNA levels correlated with distant metastasis (P = .00010) and shorter survival (P = .0071). In multivariate analysis, stage and MEN1 allelic loss were independent predictors of prognosis.
Conclusion: Thirteen percent of pulmonary carcinoids harbor MEN1 mutation associated with reduced mRNA expression and poor prognosis. Also in mutation-negative tumors, low MEN1 gene expression correlates with an adverse disease outcome. Hypermethylation was excluded as the underlying mechanism
CD44 and OTP are strong prognostic markers for pulmonary carcinoids
textabstractPurpose: Pulmonary carcinoids are well-differentiated neuroendocrine tumors showing usually a favorable prognosis. However, there is a risk for late recurrence and/or distant metast
Proximity ligation-based sequencing for the identification of human papillomavirus genomic integration sites in formalin-fixed paraffin embedded oropharyngeal squamous cell carcinomas
Human papillomavirus (HPV) infections are an increasing cause of oropharyngeal squamous cell carcinomas (OPSCC). Integration of the viral genome into the host genome is suggested to affect carcinogenesis, however, the correlation with OPSCC patient prognosis is still unclear. Research on HPV integration is hampered by current integration detection technologies and their unsuitability for formalin-fixed paraffin-embedded (FFPE) tissues. This study aims to develop and validate a novel targeted proximity-ligation based sequencing method (targeted locus amplification/capture [TLA/TLC]) for HPV integration detection in cell lines and FFPE OPSCCs. For the identification of HPV integrations, TLA/TLC was applied to 7 cell lines and 27 FFPE OPSCCs. Following preprocessing steps, a polymerase chain reaction (PCR)-based HPV enrichment was performed on the cell lines and a capture-based HPV enrichment was performed on the FFPE tissues before paired-end sequencing. TLA was able to sequence up to hundreds of kb around the target, detecting exact HPV integration loci, structural variants, and chromosomal rearrangements. In all cell lines, one or more integration sites were identified, in accordance with detection of integrated papillomavirus sequences PCR data and the literature. TLC detected integrated HPV in 15/27 FFPE OPSCCs and identified simple and complex integration patterns. In general, TLA/TLC confirmed PCR data and detected additional integration sites. In conclusion TLA/TLC reliably and robustly detects HPV integration in cell lines and FFPE OPSCCs, enabling large, population-based studies on the clinical relevance of HPV integration. Furthermore, this approach might be valuable for clonality assessment of HPV-related tumors in clinical diagnostics.</p
MEN1 Gene Mutation and Reduced Expression Are Associated with Poor Prognosis in Pulmonary Carcinoids
Losses of chromosomes 1p and 3q are early genetic events in the development of sporadic pheochromocytomas
Despite several loss of heterozygosity studies, a comprehensive genomic
survey of pheochromocytomas is still lacking. To identify DNA copy number
changes which might be important in tumor development and progression and
which may have diagnostic utility, we evaluated genetic aberrations in 29
sporadic adrenal and extra-adrenal pheochromocytomas (19 clinically benign
tumors and 10 malignant lesions). Comparative genomic hybridization was
performed using directly fluorochrome-conjugated DNA extracted from frozen
(16) and paraffin-embedded (13) tumor tissues. The most frequently
observed changes were losses of chromosomes 1p11-p32 (86%), 3q (52%), 6q
(34%), 3p, 17p (31% each), 11q (28%), and gains of chromosomes 9q (38%)
and 17q (31%). No amplification was identified and no difference between
adrenal and extra-adrenal tumors was detected. Progression to malignant
tumors was strongly associated with deletions of chromosome 6q (60% versus
21% in clinically benign lesions, P = 0.0368) and 17p (50% versus 21%).
Fluorescence in situ hybridization confirmed the comparative genomic
hybridization data of chromosomes 1p, 3q, and 6q, and revealed aneuploidy
in some tumors. Our results suggest that the development of
pheochromocytomas is associated with specific genomic aberrations, such as
losses of 1p, 3q, and 6q and gains of 9q and 17q. In particular, tumor
suppressor genes on chromosomes 1p and 3q may be involved in early
tumorigenesis, and deletions of chromosomes 6q and 17p in progression to
malignancy
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