180 research outputs found
Relationship between EGFR expression, copy number and mutation in lung adenocarcinomas
<p>Abstract</p> <p>Background</p> <p>This study was designed to investigate EGFR protein expression, EGFR copy number and EGFR mutations in lung adenocarcinomas, to explore the relationship of the three markers.</p> <p>Methods</p> <p>EGFR status was analyzed in surgically resected lung adenocarcinoma samples from 133 Chinese patients by three methods: protein expression (n = 133) by standardized immunohistochemistry (IHC), gene copy number (n = 133) by fluorescence in situ hybridization (FISH), and mutation analysis using the Scorpion amplification refractory mutation system (ARMS) (n = 133).</p> <p>Results</p> <p>The results showed that 68.4% of the samples were positive by IHC, 42.1% were positive by FISH, and 63.9% contained activating kinase domain mutations. EGFR mutations were more frequent in non-smoking patients (p = 0.008), and EGFR mutations were associated with EGFR FISH positivity (p < 0.0001). When using 10% positivity and 2+ as cutoffs, EGFR protein expression was significantly correlated with EGFR FISH positivity (p = 0.012) and EGFR mutations (p = 0.008) after Bonferroni correction.</p> <p>Conclusion</p> <p>EGFR protein expression, EGFR copy number and EGFR mutations were closely related to each other. Standard methods and interpretation criteria need to be established.</p
Analysis of EGFR, HER2, and TOP2A gene status and chromosomal polysomy in gastric adenocarcinoma from Chinese patients
<p>Abstract</p> <p>Background</p> <p>The EGFR and HER2 genes are located on chromosomes 7 and 17, respectively. They are therapeutic targets in some tumors. The TOP2A gene, which is located near HER2 on chromosome 17, is the target of many chemotherapeutic agents, and co-amplification of HER2 and TOP2A has been described in several tumor types. Herein, we investigated the gene status of EGFR, HER2, and TOP2A in Chinese gastric carcinoma patients. We determined the rate of polysomy for chromosomes 7 and 17, and we attempted to clarify the relationship between EGFR, HER2, and TOP2A gene copy number and increased expression of their encoded proteins. Furthermore, we tried to address the relationship between alterations in EGFR, HER2, and TOP2A and chromosome polysomy.</p> <p>Methods</p> <p>One hundred cases of formalin fixed and paraffin embedded tumor tissues from Chinese gastric carcinoma patients were investigated by immunohistochemistry and fluorescence in situ hybridization (FISH) methods.</p> <p>Results</p> <p>Forty-two percent of the cases showed EGFR overexpression; 16% showed EGFR FISH positive; 6% showed HER2 overexpression; and 11% showed HER2 gene amplification, including all six HER2 overexpression cases. TOP2A nuclear staining (nuclear index, NI) was determined in all 100 tumors: NI values ranged from 0.5 – 90%. Three percent of the tumors showed TOP2A gene amplification, which were all accompanied by HER2 gene amplification. Nineteen percent of the tumors showed chromosome 7 polysomy, and 16% showed chromosome 17 polysomy. Chromosome 7 polysomy correlated significantly with EGFR FISH-positivity, but was not associated with EGFR overexpression. HER2 overexpression associated significantly with HER2 gene amplification. TOP2A gene amplification was significantly associated with HER2 gene amplification. No relationship was found between alterations in the <it>EGFR</it>, <it>HER2</it>, and <it>TOP2A </it>genes and clinicopathologic variables of gastric carcinoma.</p> <p>Conclusion</p> <p>The data from our study suggest that chromosome 7 polysomy may be responsible for increased EGFR gene copy number in gastric carcinomas, and that HER2 gene amplification may be the major reason for HER2 protein overexpression. A combined investigation of the gene status of EGFR, HER2, and TOP2A should facilitate the identification of a target therapeutic regimen for gastric carcinoma patients.</p
X-ray absorption spectroscopy characterization of Zn underpotential deposition on Au(111) from phosphate supporting electrolyte
Zn K-edge X-ray absorption spectroscopy (XAS) has been used to investigate the structure of Zn monolayers prepared on Au(111) electrodes via underpotential deposition (UPD) from phosphate supporting electrolyte. Theoretical modeling of the XAS data indicates that the Zn adatoms adopt a commensurate ({radical}3x{radical}3)R30{sup o} ({mu}{sub sc} = 0.33) adlayer structure and reside within the 3-fold hollow sites of the Au(111) surface. Meanwhile, phosphate counter-ions co-adsorb on the UPD adlayer and bridge between the Zn adatoms in a ({radical}3x{radical}3)R30{sup o} ({mu}{sub sc} = 0.33) configuration, with each phosphorous atom residing above a vacant 3-fold hollow site of the Au(111). Significantly, this surface structure is invariant between the electrochemical potential for UPD adlayer formation and the onset of bulk Zn electrodeposition. Analysis of the Zn K-edge absorption onset also presents the possibility that the Zn adatoms do not fully discharge during the process of UPD, which had been proposed in prior voltammetric studies of the phosphate/Zn(UPD)/Au(111) system
A comparative clinicopathological and survival analysis of synchronous bilateral breast cancers
Objective. The present study aimed to
explore the clinicopathological characteristics, potential
heterogeneity and prognostic factors in synchronous
bilateral breast cancer (SBBC).
Methods. We performed a retrospective review and
paired comparison of the clinicopathological
characteristics of 114 patients with SBBC in the Peking
Union Medical College Hospital from January 2008 to
September 2019. The prognostic significance of triple
negativity status and coexistence ductal carcinoma in
situ (DCIS) with bilateral invasive ductal carcinomas of
no special type (IDC-NST) was analyzed in SBBC.
Results. Most bilateral lesions on both sides were of
IDC-NST, grade 2, luminal subtype, and stage I.
Although most lesions were concordant between the left
and right side, discordances were observed in
histological type (25 cases, 21.9%), histological grade
(31 cases, 27.2%), pTNM (61 cases, 53.5%), molecular
subtypes (20 cases, 17.5%), and immunohistochemical
staining of ER (18 cases, 15.8%), PR (26 cases, 22.8%),
and HER2 (12 cases, 10.5%). Moreover, there was no
significant difference in disease-free survival (DFS) and
overall survival (OS) between IDC-NST with coexisting
DCIS on both sides and IDC-NST with coexisting DCIS
on one side or pure IDC-NST. SBBC with triple
negativity on both sides exhibited a significantly shorter
DFS and OS when compared with triple negativity on
one side or non-triple negativity on both sides (p<0.001),
and remained an independent prognostic factor by
multivariate analysis.
Conclusions. A considerable proportion of
discordance in clinicopathological characteristics is
observed in SBBC, supporting the necessity of
comprehensive pathological examination including
immunohistochemical testing on both sides in clinical
practice. Moreover, SBBC with triple negativity on both
sides is a prognostic for poor survival
Primary Pulmonary Mucoepidermoid Carcinoma: Histopathological and Moleculargenetic Studies of 26 Cases.
Pulmonary mucoepidermoid carcinoma (PMEC) is an uncommon neoplasm of the lung and the main salivary gland-type lung carcinoma. The aims of this study were to review the clinicopathological and immunohistochemical features of PMEC and characterize the genetic events in PMEC.We reviewed the pathology cases in our hospital and found 34 initially diagnosed PMEC cases, 26 of which were confirmed as PMEC after excluding 8 cases of MEC-like pulmonary carcinoma. The clinicopathological characteristics of the 26 PMEC cases and the 8 cases of MEC-like pulmonary carcinoma were retrospectively reviewed. MAML2 rearrangement was detected by fluorescence In Situ Hybridization (FISH). Immunostains of ALK, calponin, collagen IV, CK7, EGFR, HER2, Ki-67, Muc5Ac, p63, p40, and TTF-1 were performed. DNA was extracted from 23 cases of PMEC. Mutation profiling of the EGFR, KRAS, BRAF, ALK, PIK3CA, PDGFRA, and DDR2 genes were carried out using next-generation sequencing (NGS), Sanger sequencing, and quantitative polymerase chain reaction (QPCR) in 9 successfully amplified cases.Twenty-six cases of PMEC (18 low-grade, 8 high-grade) included 13 men and 13 women aged 12-79 years. Twenty-two cases had a central/endobronchial growth pattern, and 4 cases had a peribronchial growth pattern. Immunohistochemically, CK7, Muc5Ac, p40, and p63 were positive in all cases (26/26);EGFR was positive in 11 cases (11/26); TTF-1, Calponin, HER2 and ALK were negative in all cases (0/26). MAML2 rearrangement was identified in 12 of 18 PMEC cases. No mutations were detected in any of the 7 genes in the 9 cases that qualified for mutation analysis. Twenty-three PMEC patients had follow-up information with a median interval of 32.6 months. Both the 5- and 10-year overall survival rates (OS) were 72.1%, and a high-grade tumor was an adverse prognostic factor in PMEC. There were 8 cases of MEC-like pulmonary carcinoma aged 36-78 years: 2 cases were located in the bronchus, and 6 cases were located in the lung. p63 and TTF-1 were positive in all cases (8/8), p40 was positive in 5 cases (5/8), and ALK was positive in 5 cases (5/8). No cases of MAML2 rearrangement were detected, but there were 5 cases of ALK rearrangement.PMEC is a primary malignant pulmonary tumor with a relatively good prognosis that is historically characterized by the presence of mucous cells and a lack of keratinization. There are distinct differences between PMEC and MEC-like pulmonary carcinoma in tumor location preference, immunophenotype, and molecular genetics, and the differential diagnosis is critical due to the therapeutic and prognostic considerations
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Primary non-Hodgkin lymphoma of the tongue base: the clinicopathology of seven cases and evaluation of HPV and EBV status.
ObjectivesNon-Hodgkin's lymphoma (NHL) primarily derived from the base of the tongue, is rare. Human papillomavirus (HPV) and Epstein-Barr virus (EBV) are important aetiological risk factors for tumours of the head and neck. This study describes the clinicopathological features of NHL in the tongue base and the status of HPV and EBV in these cases.MethodsSeven cases were identified from the Pathological Registry Database at Peking Union Medical College Hospital (PUMCH). The study utilized immunochemistry, in situ hybridization (ISH), and gene rearrangement to confirm the disease and and performed a clinical follow up for each case.ResultsAll 7 lymphomas were localized at the base of the tongue. Six of the cases exhibited tongue base masses with smooth surface membranes. One case presented as multiple deep ulcers. The most common histologic subtype was diffuse large B-cell lymphoma (DLBCL), which occurred in five cases. The other two cases were mantle cell lymphoma (MCL) and peripheral T cell lymphoma, not otherwise specified (PTCL, NOS). One of the DLBCL cases was positive for HPV DNA and diffusely expressed P16 protein. During the follow up period, the MCL patient and an elderly DLBCL patient died. The remaining five patients were alive through the end of follow up.ConclusionsMost lymphomas of the tongue base manifest as an endogenous mass without membranous change. The most common subtype of NHLs of the tongue base is DLBCL, and the occurrence at this site may have a good prognosis. With proper therapy, even late stage tongue base lymphomas can be suppressed and remain in remission
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