HER2 gene status and mRNA expression in immunohistochemistry 1+ breast cancer / 中华病理学杂志

Objective@#To investigate human epidermal growth factor 2 (HER2) gene status and in situ mRNA expression in breast cancers with immunohistochemistry(IHC) 1+ , and to reveal HER2 positive rate in these patients to provide reference data for obtaining precise HER2 results and modifying relevant clinical strategy to breast cancer.@*Methods@#Sixty-five IHC 1+ formalin-fixed and paraffin-embedded samples of invasive breast carcinoma of no special type (IBC-NST) were collected by surgical operation at Peking Union Medical College Hospital during 2011 to 2013. HER2 status and in situ mRNA expression were tested by fluorescence in situ hybridization (FISH) and RNAscope, respectively, by using tissue microarray. Metastatic lymph node was re-tested by FISH if HER2 status was equivocal or negative and with high expression of mRNA in the primary lesion.@*Results@#Four of 65 samples (6.2%) were FISH positive, which included 2 cases of HER2/CEP17>2 and average HER2 copy number>4 and 2 cases of HER2/CEP17<2 and average HER2 copy number>6. In the 4 samples of HER2 positive, 2 patients showed high in situ mRNA expression (3 scores by RNAscope), 2 patients showed moderate in situ mRNA expression (2 scores by RNAscope). In addition, 3 specimens with HER2/CEP17>2 and average HER2 copy number<4 were found in all patients, which included 2 cases of high in situ mRNA expression (3 and 4 scores by RNAscope) and 1 cases of moderate in situ mRNA expression (2 scores by RNAscope). There was no significant association between HER2 status or mRNA expression and clinicopathological characteristics, including tumor size, histopathological differentiation, lymph node metastasis and lymphovascular invasion (P>0.05).@*Conclusions@#A small number of HER2 IHC 1+ patients exist mRNA expression by using FISH method, which suggested that these patients might benefit from anti-HER2 therapy potentially. Since the importance for patients with breast cancers to develop diagnostic and therapeutic strategies from accurate molecular typing, further studies based on a larger cohort are needed to validate our findings.

HER2 mRNA expression in breast cancers with equivocal immunohistochemical results using in situ mRNA hybridization / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate in situ mRNA expression of HER2 oncogene in breast cancers with equivocal immunohistochemical results, and to explore the potential feasibility of RNAscope technique in evaluating HER2 status in breast cancers.</p><p><b>METHODS</b>Sixty-nine FFPE samples of invasive ductal breast cancer with equivocal HER2 immunohistochemistry results (IHC 2+) were collected from surgical excisions from Peking Union Medical College Hospital between June 2010 and June 2013. HER2 status and in situ mRNA expression were tested by fluorescence in situ hybridization (FISH) and RNAscope respectively using tissue microarray constructed from tumor paraffin blocks. The results of HER2 mRNA expression were scored 0 to 4 (from low to high levels) according to mRNA expression in 100 cancer cells. HER2 mRNA expression was evaluated in two groups of patients, with positive and negative FISH results.</p><p><b>RESULTS</b>Twenty-three of the 69 samples were FISH positive, including 16 samples that were scored 4 by RNAscope (70%, 16/23), 6 samples were scored 3 (26%, 6/23) and one sample was scored 2 (4%, 1/23). High in situ mRNA expression (score 4 or 3) were observed in 96% of HER2 FISH positive samples. All of samples that were scored 4 by RNAscope were FISH positive. Forty-six samples were FISH negative, including 17 samples that were scored 3 by RNAscope (37%, 17/46), 25 samples were scored 2 (54%, 25/46), and 4 samples were scored 1 (9%, 4/46).</p><p><b>CONCLUSIONS</b>Breast cancer with HER2 IHC 2+ could be further classified according to in situ mRNA expression status. Among them, RNAscope score of 4 could be one of the interpretation criteria for re-testing IHC 2+ samples. In situ detection of HER2 mRNA may be an additional candidate method of confirmation for HER2 gene amplification or protein overexpression, and has potential clinical utility.</p>

Diagnostic value of MYB protein expression in adenoid cystic carcinoma and status of MYB gene copy number / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the diagnostic value of MYB protein expression for adenoid cystic carcinoma and its differential diagnosis from other salivary gland tumors, and to further investigate the status of MYB gene copy number.</p><p><b>METHODS</b>MYB expression was studied by immunohistochemistry in 34 adenoid cystic carcinomas, 55 non-adenoid cystic carcinomas (other salivary gland tumors) including 10 pleomorphic adenomas, 10 basal cell adenomas, 10 epithelial-myoepithelial carcinomas, 9 basal cell adenocarcinomas, 8 mucoepidermoid carcinomas, 4 carcinoma in pleomorphic adenomas, and 4 polymorphous low-grade adenocarcinoma. MYB gene copy number status was detected by FISH in MYB protein-positive cases.</p><p><b>RESULTS</b>82.4% (28/34) of adenoid cystic carcinomas were MYB protein-positive, compared with 9.1% (5/55) of non-adenoid cystic carcinomas, and the difference between the two groups was statistically significant (P < 0.01). 2/18 of adenoid cystic carcinomas had duplication of MYB gene by FISH, and all non-adenoid cystic carcinomas were negative although the difference was not statistically significant (P = 0.435).</p><p><b>CONCLUSIONS</b>MYB protein expression is a useful diagnostic marker for adenoid cystic carcinomas in its separation from other salivary gland tumors. In addition, duplication of MYB gene is no a major mechanism for the MYB protein overexpression.</p>

Clinicopathologic correlation and ALK rearrangement in adenocarcinoma of lung / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate ALK gene rearrangements in lung adenocarcinomas in correlation with clinicopathologic parameters including prognosis.</p><p><b>METHODS</b>Fluorescence in situ hybridization (FISH) was used to detect ALK gene rearrangements in 53 cases of lung adenocarcinomas. Mutations in exons 18, 19, 20 and 21 of EGFR were analyzed by Scorpion amplification refractory mutation system (Scorpions ARMS).</p><p><b>RESULTS</b>In a cohort of 53 lung adenocarcinomas, ALK gene rearrangements were identified in 6 tumors (11.3%), including 4 male and 2 female patients. Five were acinar predominant adenocarcinomas and one was mucinous adenocarcinoma (P=1.000). All tumors with the ALK rearrangements had the wild-type epidermal growth factor receptor (EGFR) gene (P=0.023). The median time of disease-free survival (DFS) in ALK positive patients and negative patients were 14 months (95%CI 8.0-20.0) and 31 months (95%CI 24.9-37.1), respectively and the difference was significant (Log-rank test, P=0.019). ALK gene rearrangements were significantly associated with early recurrence, but not tumor size, pathologic stages, histological differentiation and lymph node metastasis.</p><p><b>CONCLUSIONS</b>ALK gene rearrangements are present at a higher frequency in lung adenocarcinomas of the Chinese patients. ALK gene rearrangements are mutually exclusive with EGFR mutations and associated with early tumor recurrence.</p>

ALK protein expression and gene fusion in bronchoscopic specimens of lung adenocarcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore ALK protein expression and gene fusion in formalin-fixed and paraffin-embedded (FFPE) specimens obtained from lung cancer by bronchoscopy, and to investigate the relationship between ALK status and clinicopathological characteristics of the patients.</p><p><b>METHODS</b>Seventy-four FFPE samples obtained from lung adenocarcinoma by bronchoscopy were tested for ALK protein expression and gene fusion respectively by immunohistochemistry (IHC) using Ventana D5F3 antibody and fluorescence in situ hybridization (FISH) using ALK break apart probe.</p><p><b>RESULTS</b>sixty-five of the 74 samples were successfully tested by FISH (87.8%, 65/74) . There were 5 FISH-positive cases (7.7%, 5/65) , all with advanced stage carcinoma. Among these five FISH-positive cases, 3 were IHC-positive (4.1%, 3/74) and 2 IHC-negative cases. All the other 69 samples were IHC-negative, including nine FISH-uninformative samples (7 samples were less than 50 tumor cells and 2 samples with weak FISH signal). Both ALK IHC and FISH results were not correlated with age, sex, history of smoking, histological classification, differentiation and lymph node metastasis.</p><p><b>CONCLUSIONS</b>Bronchoscopic specimens of lung cancer can be used to detect ALK expression and gene fusion. Immunohistochemistry in combination with FISH test may be more favorable for ALK test.</p>

Chromosome features of pancreatic cancer cell lines from Chinese patients / 基础医学与临床

Objective To explore the chromosome features of pancreatic cancer cell lines from Chinese patients. Methods G-band Chromosome karyotyping was performed on pancreatic cancer cell lines of PC1, PC2, PC3, PC4 and PC7 that were established in our laboratory. The results of cytogenetic analysis were confirmed by fluorescence in situ hybridization using Chromosome 3, 13 18 and 20 paint probes. Results All the 5 cell lines were hypotriploid and showed a modal number of 58 for PC1, 56 for PC2, 61 for PC3, 53 for PC4 and 54 for PC7 with different proportion of complex chromosome rearrangements including dicentric chromosomes, double-minute chromosomes, ring chromosomes, acentric fragments or complex chromosome translocation, etc. Conclusion Hapotriploid accompanied with complex numerical and structural chromosomal rearrangements is the main cytogenetic marker of chromosomal instability in pancreatic cancer cell lines. Molecular cytogenetic techniques have to be used beside conventional G-band karyotyping for accurate identifying abnormal chromosomes of pancreatic cancer cell lines.