Tumour DNA ploidy as an independent prognostic factor in breast cancer

We determined nuclear DNA content from 308 archival paraffin-embedded malignant breast tumours and evaluated the survival of the patients by univariate and multivariate statistical analyses. The overall 8-year survival rate of stage I-III breast cancer patients was 74.3% in DNA-diploid and 51.2% in DNA-aneuploid tumours (P less than 0.0001). DNA ploidy had prognostic significance in both node-negative and node-positive breast cancer, primarily in cases with steroid receptor-positive tumours. In a Cox multivariate analysis DNA ploidy (P = 0.001), primary tumour size (P = 0.0007), nodal status (P = 0.04) and the content of progesterone receptors (P = 0.0008) emerged as significant independent prognostic factors, whereas oestrogen receptor status, age and menopausal status of the patients had no significant independent prognostic value. If the histological grade of ductal carcinomas was also included in the Cox model, both grade and DNA ploidy had independent prognostic effect. In conclusion, our results indicate that the analysis of DNA ploidy is a useful adjunct in the assessment of prognosis for breast cancer patients.     

Amplifications of oncogeneerbB-2 and chromosome 20q in breast cancer determined by differentially competitive polymerase chain reaction

Summary A new method of measuring gene copy number in small samples of DNA was used to measure amplification of theerbB-2 gene and of chromosome 20q in breast cancers. This method, termed differentially competitive polymerase chain reaction (DC-PCR) combines the advantages of two other techniques for measuring amplification by PCR, namely differential PCR and competitive PCR. The DC-PCR methodology was evaluated for sensitivity and specificity by comparing amplification oferbB-2 measured by DC-PCR with that obtained by fluorescencein situ hybridization (FISH) for 42 cases or Southern blotting and/or slot blot analysis for 34 cases. There was over 90 percent concordance with both FISH and Southern blotting and/or slot blot analysis.DC-PCR was used to further characterize the newly described amplicon at chromosome 20q. By analyzing DNA from 10 breast cancer cell lines at 7 different loci, we identified a potential common region of amplification of approximately 5 centimorgans at chromosome 20q13 bordered by loci D20S52 and RMC20C001-S1. One hundred and seventeen cases of primary breast cancer were evaluated for amplification at these two loci. Amplification at one or more loci, defined as > 1.5 fold higher copy number than that of normal DNA, was found in 25 cases (21%). Sixteen cases were amplified at only one of the two probes (12 cases for RMC20C001-S1 and 4 cases for D20S52), suggesting that the target gene lies between the two markers or that there are two independent target genes within a small chromosome region.     

Prognostic impact of ANX7-GTPase in metastatic and HER2-negative breast cancer patients.

PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients.     

Immunohistochemical expression of DNA repair proteins in familial breast cancer differentiate BRCA2-associated tumors.

PURPOSE: Morphologic and immunohistochemical studies of familial breast cancers have identified specific characteristics associated with BRCA1 mutation-associated tumors when compared with BRCA2 and non-BRCA1/2 tumors, but have not identified differences between BRCA2 and non-BRCA1/2 tumors. Because BRCA1 and BRCA2 genes participate in the DNA repair pathway, we have performed an immunohistochemical study with markers related to this pathway to establish the profile of the three groups. MATERIALS AND METHODS: We have studied two tissue microarrays that include 103 familial and 104 sporadic breast tumors, with a panel of DNA repair markers including ATM, CHEK2, RAD51, RAD50, XRCC3, and proliferating cell nuclear antigen. RESULTS: We found more frequent expression of CHEK2 in BRCA1 and BRCA2 tumors than in non-BRCA1/2 and sporadic tumors. We found absence of nuclear expression and presence of cytoplasmic expression of RAD51 in BRCA2 tumors that differentiate them from other familial tumors. We validated these results with a new series of patient cases. The final study with 253 familial patient cases (74 BRCA1, 71 BRCA2, 108 non-BRCA1/2), and 288 sporadic patient cases, has allowed us to confirm our preliminary results. Because BRCA2 tumors present a specific immunohistochemical profile for RAD51 and CHEK2 markers that is different from non-BRCA1/2 tumors, we have built a multivariate model with these markers that distinguish both tumors with an estimated probability of at least 76%. CONCLUSION: Our results suggest that BRCA2 tumors demonstrate more cytoplasmic and less nuclear RAD51 staining, and increased CHEK2 staining. This pattern may distinguish BRCA2 from familial non-BRCA1/2 tumors.     

Role of ErbB4 in Breast Cancer

Members of the ErbB subfamily of receptor tyrosine kinases are important regulators of normal mammary gland physiology, and aberrations in their signaling have been associated with breast tumorigenesis. Therapeutics targeting epidermal growth factor receptor (EGFR = ErbB1) or ErbB2 in breast cancer have been approved for clinical use. In contrast, relatively little is known about the biological significance of ErbB4 signaling in breast cancer. This review focuses on recent advances in our understanding about the role of ErbB4 in breast carcinogenesis, as well as in the potential clinical relevance of ErbB4 in breast cancer prognostics and therapy.     

The impact of lobular and ductal breast cancer histology on the metastatic behavior and long term survival of breast cancer patients

The aim of the study was to evaluate the long-term survival of patients with invasive lobular carcinomas (ILC) and invasive ductal carcinomas (IDC) and the metastatic behavior of these two disease entities. Originally, all consecutive patients with pure lobular invasive breast cancers diagnosed between 1990 and 1999 in the area served by the Tampere University Hospital and their matched IDC controls were identified and re-evaluated histopathologically in this follow-up study, resulting in a total of 243 ILCs and 243 IDCs. Data on recurrences and survival were collected until the end of year 2009. Statistical analyses including Kaplan–Meier method, log-rank test, Fisher's exact test and Cox regression analysis were performed with the PASW Statistics 18.0 computer program. P-values of <0.05 were considered statistically significant.Within the mean follow-up time of 10.04 years, locoregional recurrences were significantly more common among the ILCs than IDCs (35 vs. 20, p = 0.04), but no differences in the total number of distant recurrences or bilaterality were observed. However, when the first distant recurrence sites were studied, ILC patients had significantly less lung metastases (p = 0.04), but more skin metastases (p = 0.04). During the whole follow-up period IDCs metastasized significantly more frequently to the lungs (p = 0.002), whereas gastrointestinal metastases were more common among ILCs (p = 0.02). Although the known favorable prognostic factors (hormone receptor positivity, low grade, low s-phase) were more common for the ILCs, the disease-free survival, the overall survival and the survival after recurrence did not differ between the groups. However, the Cox-regression model showed significantly worse survival for ILCs after adjusting for age, TNM-status, grade and ER-positivity (p = 0.004).In conclusion, ILC and IDC differ in respect for visceral metastases. Despite the known favorable prognostic factors and originally favorable survival, patients with lobular histology appear to have a worse survival in the multivariate analysis after a prolonged follow-up.     

Low biological aggressiveness of screen-detected lung cancers may indicate over-diagnosis

All cases of lung cancer diagnosed in the Tampere University Hospital catchment area in 1983–1987 were identified, analyzed for DNA flow cytometry and followed up to 1992. The patients were classified into 3 groups: screen-detected, symptom-detected, and detected by chance. The biological aggressiveness as indicated by DNA flow cytometry was not related to the survival of the symptom-detected patients. Also the screen-detected patients with an aggressive tumour (aneuploid or high S-phase fraction, SPF) had the same survival as the symptom-detected patients. The survival of screen-detected patients with a diploid or low SPF tumour was significantly better than that in the other groups. It is concluded that some of the previously known discrepancy of no effect on mortality and effect on survival of lung-cancer screening may be due to over-diagnosis, i.e., detection of morphologically malignant but biologically indolent lesions by screening. © 1996 Wiley-Liss, Inc.     

Spatial aspects of oncogenic signalling determine the response to combination therapy in slice explants from Kras‐driven lung tumours

A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision‐cut slices from Kras‐driven non‐small‐cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen‐activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short‐term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3‐kinase–mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology‐associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.     

Search for large genomic alterations of the BRCA1 gene in a Finnish population

Mutations in the BRCA1 and BRCA2 genes are known to predispose to breast cancer. In Finland, however, only 21% of all breast cancer families have mutations in these genes. Recent studies have shown that large genomic alterations of BRCA1 are common in many countries. Because such alterations will be missed in conventional mutation screening strategies, we decided to screen Finnish breast and ovarian cancer families for genomic alterations by using a multiplex polymerase chain reaction method. The most characteristic features of BRCA1-related breast cancer were used to select patients, namely (1) both breast and ovarian cancer in the family (48 patients), (2) four or more breast cancers in family (22 patients), or (3) young age (< or =40 years) of onset (58 patients). A total of 128 patients were included in the study. All exons of BRCA1 were analyzed but no alterations were found. This study excludes the frequent occurrence of large genomic alterations in the BRCA1 gene in Finland. Here, again, Finland differs from other countries with a mixed population structure. Our results are in agreement with the common hypothesis that there are still unknown breast cancer susceptibility gene(s) that are responsible for breast cancer predisposition.