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.

Biomarkers, Tumor ; metabolism ; Formaldehyde ; Humans ; Neoplasms ; metabolism ; Paraffin Embedding ; RNA, Messenger ; metabolism ; Tissue Fixation

OBJECTIVETo 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.

METHODSSeventy-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.

RESULTSsixty-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.

CONCLUSIONSBronchoscopic 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.

Adenocarcinoma ; metabolism ; Gene Fusion ; Humans ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Lung Neoplasms ; metabolism ; Receptor Protein-Tyrosine Kinases ; metabolism

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.

Objective To investigate in situ mRNA expression of HER 2 oncogene in breast cancers with equivocal immunohistochemical results , and to explore the potential feasibility of RNAscope technique in evaluating HER2 status in breast cancers .Methods Sixty-nine FFPE samples of invasive ductal breast cancer with equivocal HER 2 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 .Results 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).Conclusions 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 HER 2 gene amplification or protein overexpression , and has potential clinical utility.

Objective To investigate the discordant rate of HER2 gene status between primary breast cancer and synchronous axillary lymph node metastasis.Methods One hundred and fifty cases of primary breast cancer with corresponding synchronous lymph node metastases were collected,including 50 cases of HER2 FISH positive,50 cases of HER2 FISH negative and 50 cases of HER2 FISH equivocal primary tumors,at Peking Union Medical College Hospital between May 2012 and June 2015.The HER2 gene status in lymph node metastatic tumors was analyzed by FISH,and the discordance of HER2 gene status was identified between primary and metastatic tumors.Results The incidence of discordant HER2 gene status between primary breast cancer and synchronous lymph node metastasis was 20.67％ (31/150).Fortyfour FISH positive,3 FISH equivocal and 3 FISH negative cases were found in the first group of 50 patients with HER2 positive results in primary tumor.Forty seven FISH negative,3 FISH equivocal cases were discovered in the second group of 50 patients with HER2 negative results in primary tumor.Four FISH positive,18 FISH negative and 28 equivocal cases were observed in the third group of 50 patients with HER2 equivocal results in primary tumor.The discordance of HER2 gene status between primary tumor and lymph node metastasis in the third group of patients was significantly higher than the other two groups (P ＜ 0.05).Conclusions Significant discordance of HER2 gene status between the primary and lymph node metastatic tumors exists.Patients with lymph node metastasis,simultaneous testing of HER2 status may be performed in both primary breast tumor and its lymph node metastasis.HER2 status of nodal metastatic lesion may be more relevant for guiding anti-HER2 target therapy.

Objective:To investigate HER2 mRNA expression in breast cancer with HER2 immunohistochemistry (IHC) 0 and to analyze the feasibility of distinguishing between the tumor with HER2 μltra-low expression and the one without expression of HER2 (no staining by IHC) by HER2 mRNA level preliminarily.Methods:HER2 mRNA was analyzed by reverse transcription digital PCR in 41 cases of formalin-fixed paraffin-embedded surgical tissue samples of invasive breast cancer obtained between January 2020 and March 2023 at Peking Union Medical College Hospital. The cohort included 21 HER2 IHC 1+ and 20 IHC 0 (12 ultra-low and 8 non-expression of HER2). HER2 mRNA expression level was quantitatively evaluated by the FAM (HER2)/VIC (reference gene) ratio.Results:The expression of HER2 mRNA for the cases with 1+, ultra-low, and non-expression of HER2 by IHC was 0.30 to 1.78 (average 0.90, median 0.82), 0.55 to 1.51 (average 0.93, median 0.90) and 0.22 to 0.78 (average 0.41, median 0.36), respectively. For the mean and median HER2 mRNA levels, there was no significant difference between HER2 IHC 1+ and HER2 ultra-low expression diseases ( P=0.757). A remarkable difference in HER2 gene expression was found between the tumors with 1+ and non-expression of HER2 by IHC ( P=0.002). And, HER2 ultra-low cases contained statistically higher levels of HER2 mRNA compared with non-expression of HER2 subgroup by IHC ( P=0.001). Conclusions:Based on HER2 mRNA, HER2 non-expression and HER2 weak expression (including HER2 IHC 1+ and ultra-low) belong to two different types of the tumor and the disease with HER2 IHC 1+ and HER2 ultra-low expression may be the same. It is necessary to further test the performance of HER2 mRNA detection for stratifying the HER2 weak expression subgroup and to determine the threshold.

Objective 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 .Methods 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.Results 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).Conclusions 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 .

Objective:To investigate the clinical and pathological characteristics of breast cancer with HER2 low expression.Methods:The data from 3 422 patients with invasive breast cancer which archived in Peking Union Medical College Hospital between April 2019 and July 2022 were retrospectively reviewed. Among them, 136 patients were treated with neoadjuvant chemotherapy. The tumor size, histological type, tumor differentiation, lymph node metastasis, Ki-67 index, the status of estrogen receptor, progesterone receptor and HER2 as well as pathological complete response (pCR) rate were collected.Results:The HER2 status of 3 286 patients without neoadjuvant therapy, 616 (616/3 286, 18.7%) score 0, 1 047 (1 047/3 286, 31.9%) score 1+, 1 099 (1 099/3 286,33.4%) score 2+ and 524 (524/3 286,15.9%) score 3+ by immunohistochemistry (IHC). Among the 1 070 IHC 2+ cases, 161 were classified as HER2 positive by reflex fluorescence in situ hybridization (FISH) assay. In our cohort, 1 956 cases of HER2-low (IHC 1+ and IHC 2+/FISH-) breast cancer were identified. Compared to the HER2 IHC 0 group, HER2-low tumors more frequently occurred in patients with hormone receptor (HR) positive ( P<0.001), Ki-67 index below 35% ( P<0.001), well or moderate differentiation ( P<0.001) and over the age of 50 ( P=0.008). However, there were no significant differences in histological type, tumor size, and lymph node metastasis between HER2-low and HER2 IHC 0 group. For patients who had neoadjuvant therapy, the pCR rate in the patients with HER2-low was lower than those with HER2 IHC 0 (13.3%, 23.9%), but there was no significant difference. Although HER2-low breast cancers showed a slightly lower pCR rate than HER2 IHC 0 tumors, no remarkable difference was observed between tumors with HER2-low and HER2 IHC 0 regardless of hormone receptor status. Conclusions:The clinicopathological features of HER2-low breast cancers are different from those with HER2 IHC 0. It is necessary to accurately distinguish HER2-low breast cancer from HER2 IHC 0 and to reveal whether HER2-low tumor is a distinct biological entity.

OBJECTIVETo investigate ALK gene rearrangements in lung adenocarcinomas in correlation with clinicopathologic parameters including prognosis.

METHODSFluorescence 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).

RESULTSIn 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.

CONCLUSIONSALK 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.

Adenocarcinoma, Mucinous ; genetics ; pathology ; surgery ; Adult ; Aged ; Aged, 80 and over ; Carcinoma, Acinar Cell ; genetics ; pathology ; surgery ; Disease-Free Survival ; Exons ; Female ; Follow-Up Studies ; Gene Rearrangement ; Humans ; Lung Neoplasms ; genetics ; pathology ; surgery ; Male ; Middle Aged ; Mutation ; Neoplasm Recurrence, Local ; Neoplasm Staging ; Receptor Protein-Tyrosine Kinases ; genetics ; Receptor, Epidermal Growth Factor ; genetics