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C-erbB-2 oncoprotein amplification in infiltrating ductal carcinoma of breast relates to high histological grade and loss of oestrogen receptor protein

Looi LM, Cheah PL

Malays J Pathol, 1998 Jun;20(1):19-23.
PMID: 10879259

Eighty-six infiltrating ductal carcinoma of breast were studied by the standard avidin-biotin complex immunoperoxidase method on formalin-fixed, paraffin-embedded tissue sections, for oestrogen receptor (ER) protein and c-erbB-2 oncoprotein expression. They were categorized according to the modified Bloom and Richardson criteria into three histological grades. 21% tumours were ER positive while 44% were c-erbB-2 positive. Of ER positive tumours, 33.3% were c-erbB-2 positive whereas the c-erbB-2 positivity rate was much higher (47.1%) in ER negative tumours. Only 16% of c-erbB-2 positive tumours were ER positive while 25% of c-erbB-2 negative tumours were ER positive. This negative relationship between ER and c-erbB-2 expression was statistically significant (Mc Nemar's test, p < 0.005). The ER positivity rate did not vary significantly with histological grade. However, c-erbB-2 overexpression was significantly more prevalent in grade III tumours compared with grade I and II tumours (Chi-square test, p < 0.005). Since the c-erbB-2 oncogene has extensive structural homology to the epidermal growth factor receptor (EGFR) gene, we expect that c-erbB-2 oncoprotein would share functional similarities with EGFR leading to both loss of oestrogen receptor and poor prognosis in breast cancer. Its overexpression can be expected to relate to more aggressive tumour proliferation and may explain its correlation with high histological grade, a known indicator of aggressive cancer behaviour. As there is no indication that ER protein activity contributes to advancement in histological grade, it would appear that cellular dedifferentiation precedes ER loss during malignant transformation. It has been mooted that ER positive breast cancers which also show c-erbB-2 oncoprotein overexpression have a poorer response to hormonal therapy. The use of this parameter in the routine assessment of breast cancer patients may identify subsets of patients for more aggressive therapy.

Matched MeSH terms: Carcinoma, Ductal, Breast/pathology
Fulltext Guideline implementation for breast healthcare in low- and middle-income countries: early detection resource allocation

Yip CH, Smith RA, Anderson BO, Miller AB, Thomas DB, Ang ES, et al.

Cancer, 2008 Oct 15;113(8 Suppl):2244-56.
PMID: 18837017 DOI: 10.1002/cncr.23842

A key determinant of breast cancer outcome in any population is the degree to which cancers are detected at early stages of disease. Populations in which cancers are detected at earlier stages have lower breast cancer mortality rates. The Breast Health Global Initiative (BHGI) held its third Global Summit in Budapest, Hungary in October 2007, bringing together internationally recognized experts to address the implementation of breast healthcare guidelines for early detection, diagnosis, and treatment in low- and middle-income countries (LMCs). A multidisciplinary panel of experts specifically addressed the implementation of BHGI guidelines for the early detection of disease as they related to resource allocation for public education and awareness, cancer detection methods, and evaluation goals. Public education and awareness are the key first steps, because early detection programs cannot be successful if the public is unaware of the value of early detection. The effectiveness and efficiency of screening modalities, including screening mammography, clinical breast examination (CBE), and breast self-examination, were reviewed in the context of resource availability and population-based need by the panel. Social and cultural barriers should be considered when early detection programs are being established, and the evaluation of early detection programs should include the use of well developed, methodologically sound process metrics to determine the effectiveness of program implementation. The approach and scope of any screening program will determine the success of any early detection program as measured by cancer stage at diagnosis and will drive the breadth of resource allocation needed for program implementation.

Matched MeSH terms: Breast/pathology
Fulltext Long-term exposure to insulin and volumetric mammographic density: observational and genetic associations in the Karma study

Borgquist S, Rosendahl AH, Czene K, Bhoo-Pathy N, Dorkhan M, Hall P, et al.

Breast Cancer Res, 2018 08 09;20(1):93.
PMID: 30092829 DOI: 10.1186/s13058-018-1026-7

BACKGROUND: Long-term insulin exposure has been implicated in breast cancer etiology, but epidemiological evidence remains inconclusive. The aims of this study were to investigate the association of insulin therapy with mammographic density (MD) as an intermediate phenotype for breast cancer and to assess associations with long-term elevated circulating insulin levels using a genetic score comprising 18 insulin-associated variants.
METHODS: We used data from the KARolinska MAmmography (Karma) project, a Swedish mammography screening cohort. Insulin-treated patients with type 1 (T1D, n = 122) and type 2 (T2D, n = 237) diabetes were identified through linkage with the Prescribed Drug Register and age-matched to 1771 women without diabetes. We assessed associations with treatment duration and insulin glargine use, and we further examined MD differences using non-insulin-treated T2D patients as an active comparator. MD was measured using a fully automated volumetric method, and analyses were adjusted for multiple potential confounders. Associations with the insulin genetic score were assessed in 9437 study participants without diabetes.
RESULTS: Compared with age-matched women without diabetes, insulin-treated T1D patients had greater percent dense (8.7% vs. 11.4%) and absolute dense volumes (59.7 vs. 64.7 cm3), and a smaller absolute nondense volume (615 vs. 491 cm3). Similar associations were observed for insulin-treated T2D, and estimates were not materially different in analyses comparing insulin-treated T2D patients with T2D patients receiving noninsulin glucose-lowering medication. In both T1D and T2D, the magnitude of the association with the absolute dense volume was highest for long-term insulin therapy (≥ 5 years) and the long-acting insulin analog glargine. No consistent evidence of differential associations by insulin treatment duration or type was found for percent dense and absolute nondense volumes. Genetically predicted insulin levels were positively associated with percent dense and absolute dense volumes, but not with the absolute nondense volume (percentage difference [95% CI] per 1-SD increase in insulin genetic score = 0.8 [0.0; 1.6], 0.9 [0.1; 1.8], and 0.1 [- 0.8; 0.9], respectively).
CONCLUSIONS: The consistency in direction of association for insulin treatment and the insulin genetic score with the absolute dense volume suggest a causal influence of long-term increased insulin exposure on mammographic dense breast tissue.

Matched MeSH terms: Breast/pathology
Fulltext Structural Studies of Epithelial Mesenchymal Transition Breast Tissues

Mohd Sobri SN, Abdul Sani SF, Sabtu SN, Looi LM, Chiew SF, Pathmanathan D, et al.

Sci Rep, 2020 02 06;10(1):1997.
PMID: 32029810 DOI: 10.1038/s41598-020-58932-5

At the supramolecular level, the proliferation of invasive ductal carcinoma through breast tissue is beyond the range of standard histopathology identification. Using synchrotron small angle x-ray scattering (SAXS) techniques, determining nanometer scale structural changes in breast tissue has been demonstrated to allow discrimination between different tissue types. From a total of 22 patients undergoing symptomatic investigations, different category breast tissue samples were obtained in use of surgically removed tissue, including non-lesional, benign and malignant tumour. Structural components of the tissues were examined at momentum transfer values between q = 0.2 nm-1 and 1.5 nm-1. From the SAXS patterns, axial d-spacing and diffuse scattering intensity were observed to provide the greatest discrimination between the various tissue types, specifically in regard to the epithelial mesenchymal transition (EMT) structural component in malignant tissue. In non-lesional tissue the axial period of collagen is within the range 63.6-63.7 nm (formalin fixed paraffin embedded (FFPE) dewaxed) and 63.4 (formalin fixed), being 0.9 nm smaller than in EMT cancer-invaded regions. The overall intensity of scattering from cancerous regions is a degree of magnitude greater in cancer-invaded regions. Present work has found that the d-spacing of the EMT positive breast cancer tissue (FFPE (dewaxed)) is within the range 64.5-64.7 nm corresponding to the 9th and 10th order peaks. Of particular note in regard to formalin fixation of samples is that no alteration is observed to occur in the relative differences in collagen d-spacing between non-lesional and malignant tissues. This is a matter of great importance given that preserved-sample and also retrospective study of samples is greatly facilitated by formalin fixation. Present results indicate that as aids in tissue diagnosis SAXS is capable of distinguishing areas of invasion by disease as well as delivering further information at the supramolecular level.

Matched MeSH terms: Breast/pathology; Carcinoma, Ductal, Breast/pathology*
Single-nucleotide polymorphisms and mRNA expression of CYP1B1 influence treatment response in triple negative breast cancer patients undergoing chemotherapy

Abdul Aziz AA, Md Salleh MS, Mohamad I, Krishna Bhavaraju VM, Mazuwin Yahya M, Zakaria AD, et al.

J Genet, 2018 Dec;97(5):1185-1194.
PMID: 30555068

Triple negative breast cancer (TNBC) is typically associated with poor and interindividual variability in treatment response. Cytochrome P450 family 1 subfamily B1 (CYP1B1) is a metabolizing enzyme, involved in the biotransformation of xenobiotics and anticancer drugs. We hypothesized that, single-nucleotide polymorphisms (SNPs), CYP1B1 142 C>G, 4326 C>G and 4360 A>G, and CYP1B1 mRNA expression might be potential biomarkers for prediction of treatment response in TNBC patients. CYP1B1 SNPs genotyping (76 TNBC patients) was performed using allele-specific polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism methods and mRNA expression of CYP1B1 (41 formalin-fixed paraffin embeddedblocks) was quantified using quantitative reverse transcription PCR. Homozygous variant genotype (GG) and variant allele (G) of CYP1B1 4326C>G polymorphism showed significantly higher risk for development of resistance to chemotherapy with adjusted odds ratio (OR): 6.802 and 3.010, respectively. Whereas, CYP1B1 142 CG heterozygous genotype showed significant association with goodtreatment response with adjusted OR: 0.199. CYP1B1 142C-4326G haplotype was associated with higher risk for chemoresistance with OR: 2.579. Expression analysis revealed that the relative expression of CYP1B1 was downregulated (0.592) in cancerous tissue compared with normal adjacent tissues. When analysed for association with chemotherapy response, CYP1B1 expression was found to be significantly upregulated (3.256) in cancerous tissues of patients who did not respond as opposed to those of patients who showed response to chemotherapy. Our findings suggest that SNPs together with mRNA expression of CYP1B1 may be useful biomarkers to predict chemotherapy response in TNBC patients.

Matched MeSH terms: Carcinoma, Ductal, Breast/pathology