Shafei Wu

Analysis of EGFR, HER2, and TOP2A gene status and chromosomal polysomy in gastric adenocarcinoma from Chinese patients

BackgroundThe 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.MethodsOne 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.ResultsForty-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 EGFR, HER2, and TOP2A genes and clinicopathologic variables of gastric carcinoma.ConclusionThe 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.

Relationship between EGFR expression, copy number and mutation in lung adenocarcinomas.

BackgroundThis 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.MethodsEGFR 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).ResultsThe 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.ConclusionEGFR protein expression, EGFR copy number and EGFR mutations were closely related to each other. Standard methods and interpretation criteria need to be established.

Chromosome 1q loss of heterozygosity frequently occurs in sporadic insulinomas and is associated with tumor malignancy

The pathogenesis of sporadic insulinomas is not clear, and there are no reliable genetic determinants that are useful to distinguish malignant and benign forms of this tumor. It was reported that 1q LOH might contribute to pathogenesis in gastrinomas and was correlated with tumor progression. However, little data are available on 1q LOH in sporadic insulinomas. In our study, we determine whether 1q LOH occurs in sporadic insulinomas and is associated with tumor malignancy by performing 1q allelotyping with 17 markers in 40 tumors and pair normal DNA. Thirty‐five (88%) insulinomas had 1q LOH. Of the 35 insulinomas with 1q LOH, 14 (40%) had 1q21.3‐23.2 LOH over a 7.5 cM region (SRO‐1), whereas LOH in 21 tumors (60%) occurred at 1q31.3 over an 11.4 cM area (SRO‐2). Of 24 tumors without MEN1 LOH, 20 had either SRO‐1 or SRO‐2 LOH (83%), whereas in 16 tumors with MEN1 LOH, 9 were shown to have LOH at either SRO‐1 or SRO‐2 (56%) (p = 0.065). This result suggests that LOH at 2 SRO might be MEN1 gene independent and may contribute to the pathogenesis in a subset of insulinomas without MEN1 gene LOH. The presence of 1q21.3‐23.2 LOH is significantly associated with malignancy of insulinomas (p = 0.014). The high frequency of LOH at 1q 21.3‐23.2 and 1q31.3 suggests these 2 areas may harbor putative tumor suppressor genes that may play an important role in the tumorigenesis of a subset of insulinomas. LOH at 1q21.3‐23.2, which was associated with tumor malignancy, could be one of the genetic markers for identifying malignancy in sporadic insulinomas.

Patterns of K-ras codon 12 and 13 mutations found in pancreatic adenocarcinoma of 30 Chinese patients by microdissection, PCR and direct sequencing

Background and Aim:  To our knowledge there are few reports on the K‐ras mutation pattern of pancreatic adenocarcinoma from Chinese mainland patients. We examined surgically resected formalin‐fixed, paraffin‐embedded primary pancreatic adenocarcinoma tissue blocks for the presence of activating point mutations at codon 12 and 13 of the K‐ras gene.

DNAzyme‐mediated cleavage of survivin mRNA and inhibition of the growth of PANC‐1 cells

Background and Aim:  Survivin has functions in both the regulation of cell division and the inhibition of apoptosis, and it is expressed in most human tumors but not in normal adult tissues. It is a potential target for cancer gene therapy. In the present study, we designed a DNAzyme targeting human survivin mRNA and tried to determine its effect on human pancreatic carcinoma cell line PANC‐1.

The significance of programmed cell death ligand 1 expression in resected lung adenocarcinoma

Background Lung adenocarcinoma (AD) is a common variant of non-small cell lung cancer (NSCLC). Programmed cell death protein 1/programmed cell death ligand 1 (PD1/PD-L1) are promising immunotherapy targets and its expression may be an important biomarker of predicting clinical response. In this study, we evaluated PD-L1 expression in conjunction with clinicopathological characteristics and outcomes in resected lung adenocarcinoma. Results This study included 133 cases of lung adenocarcinoma. PD-L1 expression rate in lung adenocarcinoma was 16.5% at the mRNA level and 13.5% at the protein level, and the kappa coefficient of the two examination methods was 0.824 (P = 0.219, highly correlated). PD-L1 was highly expressed in male patients and smokers with lung adenocarcinoma (P = 0.019 and 0.002, respectively), while no associations were identified between PD-L1 expression and age, tumor size, clinical stage, positive pleural invasion, lymph node metastasis, or therapy methods. Overexpression of PD-L1 was a significant indicator of shorter recurrence free survival time and overall survival (P = 0.000 and 0.000, respectively). Multivariate analysis revealed that PD-L1 expression was an independent risk factor for poor recurrence free survival and overall survival (P = 0.009 and 0.016, respectively). Materials and Methods Expression of PD-L1 was examined with immunohistochemistry, using the VENTANA PD-L1 (SP263) rabbit monoclonal antibody. mRNA levels of PD-L1 were evaluated using in situ hybridization. Conclusions PD-L1 overexpression is more frequently observed in male patients and smokers in lung adenocarcinoma. PD-L1 expression is an indicator of worse prognosis in surgically resected lung adenocarcinoma patients.

Primary Pulmonary Mucoepidermoid Carcinoma: Histopathological and Moleculargenetic Studies of 26 Cases

Introduction 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. Methods 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. Results 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. Conclusions 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.

PD-L1 expression in lung adenosquamous carcinomas compared with the more common variants of non-small cell lung cancer

Lung adenosquamous cell carcinomas (ASCs) is a rare variant of NSCLC with a poorer prognosis and fewer treatment option than the more common variants. PD-L1 expression is reported to be the predictor of clinical response in trials of NSCLC. In our study, PD-L1 expression was evaluated via immunohistochemistry using a specific monoclonal antibody (SP263), and PD-L1 mRNA expression was evaluated via in situ hybridization. This study included 51 ASCs, 133 lung adenocarcinomas, and 83 lung squamous cell carcinomas (SCC). Similar results were obtained for PD-L1 expression measured at the mRNA and protein level (k coefficient, 0.851, P = 1.000). PD-L1 expression was significantly higher in the squamous versus glandular component of the 36 ASCs in which the components were analyzed separately. The PD-L1 expression rate was similar in the squamous cell component of ASCs and lung SCC (38.89% vs. 28.92%, P = 0.293), so does the adenocarcinoma component of ASCs and lung adenocarcinomas (11.11% vs 13.53%, P = 1.000). PD-L1 expression correlated significantly with lymphovascular invasion (P = 0.016), but not with EGFR, KRAS, and ALK mutations in lung ASCs. Anit-PD-L1 is a promising treatment option in lung ASC cases in which PD-L1 upregulated and EGFR mutations are present.

Fluorescence In Situ Hybridization with the UroVysion Kit for the Detection of Biliary Cancer in Chinese Patients

BACKGROUND Conventional biliary brush via ERCP has low clinical detection for biliary malignancy. Therefore, new approaches are needed to facilitate diagnosis. We therefore explored the application of fluorescent in situ hybrization (FISH) using a UroVysion kit for the detection of malignancy in the bile duct. METHODS Genetic alterations of target chromosomes such as aneuploidy in Chinese biliary cancer cell lines and tissues were measured using a UroVysion kit. The diagnostic value of the FISH assay was assessed by probing 27 brush samples of biliary cytology and control routine cytology (RC) samples. The gold standard was established by the pathology or clinical outcomes at the 12-month follow-up. RESULTS Aneuploidy is commonly found in cell lines and tissues of biliary cancers, but not in normal cells or tissues. Here we probed for aneuploidy in clinical biliary brush specimens obtained by ERCP using FISH and a UroVysion kit. The sensitivity, specificity, and positive and negative predictive values for biliary malignancy were found to be 50%, 100%, 100% and 31.3%, respectively. The sensitivity, specificity, and positive and negative predictive values by RC were found to be 22.7%, 100%, 100% and 22.7%, respectively. In combination with RC, FISH increased the diagnostic sensitivity to 63.6% although this difference was not found to be statistically significant. CONCLUSIONS Aneuploidy is frequently present in bile duct carcinomas. Here we found that the FISH assay is useful for the detection of Chinese biliary cancers.

Adrenal cortical neoplasms: a study of clinicopathological features related to epidermal growth factor receptor gene status

BackgroundAdrenocortical carcinoma (ACC) is a rare but highly malignant neoplasm with limited treatment options.MethodsIn this study, the clinicopathological features of 22 ACCs and 22 adrenocortical adenomas (ACA) were analyzed, and the EGFR protein expression, EGFR gene mutation status and EGFR gene copy number alteration of all tumors were examined using immunohistochemistry, fluorescence in situ hybridization (FISH), and the Scorpion Amplification Refractory Mutation System (ARMS), respectively.ResultsEGFR protein expression was detected in 63.6% of the ACC samples, and EGFR FISH was positive in 50% of the ACC samples (all were high polysomy on chromosome 7). In contrast, 27.3% of the ACA samples demonstrated EGFR expression, and none of the ACA samples tested positive by FISH. There were significant differences between the ACC and ACA in terms of protein expression (P = 0.035) and gene copy number alterations (P < 0.001).ConclusionsEGFR protein expression and high polysomy on chromosome 7 are frequent abnormalities in ACC than in ACA.Virtual slidesThe virtual slide(s) for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/2068470757103500.