Multi-elemental quantitative analyses of 15 paired samples of normal and malignant human breast tissue by instrumental neutron activation analysis are reported. The elements, Al, Br, Ca, Cl, Co, Cs, Fe, K, Na, Rb, Zn were detected. Significantly elevated concentration levels were found for Al, Br, Ca, Cl, Cs, K, Na, Zn in malignant compared to normal tissue. Although the role of elemental composition in breast cancer is unclear, this finding may be of importance as another parameter for differentiating normal from malignant tissue.
Fresh frozen neoplastic tissues from 70 infiltrating ductal breast carcinomas were analysed for cytosolic oestrogen receptor (ER) protein content using a solid phase enzyme immunoassay (EIA) method based on a "sandwich" principle (Abbott ER-EIA monoclonal). Formalin-fixed, paraffin-embedded sections from the same carcinomas were examined for nuclear immunoreactivity against a monoclonal antibody for ER protein (Dako) using the standard avidin-biotin complex immunoperoxidase (IP) method after microwave antigen retrieval. The degree of ER positivity by IP was also scored according to a visual estimation of the percentage of cells expressing immunopositivity and the intensity of staining. Twenty-eight (40%) of the carcinomas were ER-positive by EIA and 34 (48.6%) were positive by IP. Twenty-five (35.7%) were ER-positive and 33 (47.1%) were ER-negative by both methods. Nine (12.9%) were ER-negative by EIA but were positive by IP, this discrepancy being ascribed to sampling inadequacy for EIA. However, 3 (4.3%) tumours were ER-positive by EIA and negative by IP. This discrepancy may be variously due to inadequate antigen retrieval, faulty technique and the possibility that the two methods do not measure identical ER proteins. IP appears to have an advantage over EIA in that it has a higher pick-up rate, does not require fresh tissue and can be applied to archival material. However, to reduce false negative estimations, it may be necessary to run IP staining using more than one ER antibody. Standardisation of the IP method for ER is desirable before this method is to be widely adopted in Malaysian laboratories. Quantitation of ER positivity by IP scoring correlated poorly with actual cytosolic levels. Caution should be exercised in attaching patient management value to visual IP scoring.
The epithelial-mesenchymal transition (EMT) is a crucial process in cancer progression and metastasis. Study of metabolic changes during the EMT process is important in seeking to understand the biochemical changes associated with cancer progression, not least in scoping for therapeutic strategies aimed at targeting EMT. Due to the potential for high sensitivity and specificity, Raman spectroscopy was used here to study the metabolic changes associated with EMT in human breast cancer tissue. For Raman spectroscopy measurements, tissue from 23 patients were collected, comprising non-lesional, EMT and non-EMT formalin-fixed and paraffin embedded breast cancer samples. Analysis was made in the fingerprint Raman spectra region (600-1800 cm-1) best associated with cancer progression biochemical changes in lipid, protein and nucleic acids. The ANOVA test followed by the Tukey's multiple comparisons test were conducted to see if there existed differences between non-lesional, EMT and non-EMT breast tissue for Raman spectroscopy measurements. Results revealed that significant differences were evident in terms of intensity between the non-lesional and EMT samples, as well as the EMT and non-EMT samples. Multivariate analysis involving independent component analysis, Principal component analysis and non-negative least square were used to analyse the Raman spectra data. The results show significant differences between EMT and non-EMT cancers in lipid, protein, and nucleic acids. This study demonstrated the capability of Raman spectroscopy supported by multivariate analysis in analysing metabolic changes in EMT breast cancer tissue.
Vascular endothelial growth factor (VEGF) is a leading factor for tumour angiogenesis and p53 protein is the product of a tumor suppressor gene. The main aim of the study was to assess the association of p53 protein with VEGF expression in breast carcinoma.
INTRODUCTION: The age standardised incidence rate (ASR) of breast cancer in Malaysia which is a high middle- income country is similar to Indonesia, a low middle-income country. (Globocan 2008) It is however unknown whether the presentation of breast cancer differs between these two countries.
OBJECTIVE: We compared the stage, age at presentation, and pathological characteristics of breast cancer between two tertiary hospitals in Indonesia and Malaysia; Dharmais Cancer Centre (DCC), which is the national cancer referral centre in Indonesia, and University Malaya Medical Centre (UMMC), which is an academic hospital with established breast oncology services in Kuala Lumpur. One thousand, one hundred and fourteen consecutive women (477 in UMMC: 637 in DCC) who were newly diagnosed with breast cancer between January and December, 2010 were included. Patient's age, TNM stage at presentation, and pathological characteristics were compared. Estrogen receptor (ER) and progesterone receptor (PR) were considered positive if 10% or greater of invasive cell nuclei were stained while HER2 was considered positive with an immunohistochemistry staining intensity of 3+ . Logistic regression analyses were performed to identify differences.
RESULTS: Median age at diagnosis was 52 years in UMMC and 47 years in DCC, whereby patients in DCC were more likely to be very young at diagnosis (aged < 35 years) compared to their counterparts in UMMC (Odds ratio (OR): 2.09; 95%CI: 1.32-3.31). Approximately one third of patients in UMMC presented with TNM stage III or IV, compared to 63% in DCC. Patients in DCC were three times more likely to present with metastatic breast cancer compared to patients in UMMC (OR: 3.01; 95% CI: 2.02-4.48). The percentage of low grade tumours in DCC was higher than in UMMC (28% vs 11% respectively), and the difference persisted even after multivariate adjustment. Although the frequency of ER and PR positivity appeared to be higher in UMMC (65% and 55% respectively) compared to DCC (48% and 40% respectively), these differences were not statistically significant following adjustment for age, stage, HER2 status and grade. The frequency of HER2 positivity was 45% in DCC compared to 26% in UMMC, and remained significantly higher even after multivariate adjustment (multivariate OR:1.76; 95%CI:1.25-2.47, in DCC compared to UMMC). The proportion of triple negative breast cancer was however similar in the two centres (19% in UMMC vs 21% in DCC).
CONCLUSION: Indonesian women with breast cancer seem to present at a younger age and at later stages compared to Malaysian women. Their tumors were more likely to be of low grade and HER2 positive, even after adjustment for other factors, while hormone receptor positivity proved similar in the two groups. The higher HER2 positivity rate in Indonesian patients warrants further study.
Discriminant analysis of six trace element concentrations measured by instrumental neutron activation analysis (INAA) in 26 paired-samples of malignant and histologically normal human breast tissues shows the technique to be a potentially valuable clinical tool for making malignant-normal classification. Nonparametric discriminant analysis is performed for the data obtained. Linear and quadratic discriminant analyses are also carried out for comparison. For this data set a formal analysis shows that the elements which may be useful in distinguishing between malignant and normal tissues are Ca, Rb and Br, providing correct classification for 24 out of 26 normal samples and 22 out of 26 malignant samples.
The traditional classification of infiltrating breast carcinomas into ductal and lobular can be diagnostically challenging in a small proportion of cases with equivocal histological features and in in-situ lesions with overlapping features. Distinguishing between the infiltrating ductal (IDC) and lobular (ILC) carcinomas is clinically important because of the different pattern of systemic metastases and prognostic evaluation. E-cadherin is a potentially useful immunohistochemical marker which may serve to differentiate between the two tumour types. We therefore studied E-cadherin expression in 32 cases of breast carcinomas comprising 16 IDCs and 16 ILCs. The correlation between E-cadherin expression and the histological grade of IDCs was also analysed. Our results showed complete loss of E-cadherin expression in all ILCs, while the IDCs consistently showed variable E-cadherin positivity. No significant correlation was found between E- cadherin expression and the histological grade of IDCs. We conclude from this study that E-cadherin is a useful marker to differentiate between IDC and ILC of the breast. A larger study of IDCs is now needed to further evaluate the correlation between E-cadherin and tumour grade to estimate its prognostic potential.
In settings with limited resources, sentinel lymph node biopsy (SNB) is only offered to breast cancer patients with small tumors and a low a priori risk of axillary metastases.
This investigation was carried out to gain insight into the prevalence of pS2 expression in invasive ductal breast carcinoma in the Malaysian population and its correlation with oestrogen receptor (ER) protein expression and tumour aggressiveness. Seventy consecutive infiltrating ductal breast carcinomas treated with mastectomy and axillary lymph node clearance were investigated, using the standard avidin-biotin complex immunoperoxidase method with microwave antigen retrieval and commercial monoclonal antibodies (Dako), for expression of pS2 and human ER. This was correlated against histological grade (modified Bloom and Richardson) and the presence of axillary lymph node metastasis of these carcinomas. Four (5.7%) were grade 1, 40 (57.1%) grade 2 and 26 (37.1%) grade 3 tumours. A total of 45 (64%) showed histological evidence of axillary lymph node metastasis. Forty (57%) were ER-positive, while 31 (44%) were pS2-positive. There was a statistically significant correlation between pS2 and ER expressions (chi2-test with Yates correction: P<0.005). There was no correlation between pS2 expression and histological grade (P>0.1) and the presence of lymph node metastasis (P>0.1). Our findings support the views that pS2 may be a co-marker of endocrine responsiveness in invasive breast cancer and that it does not influence breast cancer biology in terms of potential for metastatic spread.
Copper complexes have been widely studied for the anti-tumour application as cancer cells are reported to take up greater amounts of copper than normal cells. Preliminary study revealed that the newly synthesised copper complex [Cu(SBCM)2] displayed marked anti-proliferative towards triple-negative MDA-MB-231 breast cancer cells. Therefore, Cu(SBCM)2 has great potential to be developed as an agent for the management of breast cancer. The present study was carried out to investigate the mode of cell death induced by Cu(SBCM)2 towards MDA-MB-231 breast cancer cells. The inhibitory and morphological changes of MDA-MB-231 cells treated with Cu(SBCM)2 was determined by using MTT assay and inverted light microscope, respectively. The safety profile of Cu(SBCM)2 was also evaluated towards human dermal fibroblast (HDF) normal cells. Confirmation of apoptosis and cell cycle arrest were determined by flow cytometry analysis. The expression of p53, Bax, Bcl-2 and MMP2 protein were detected with western blot analysis. Cu(SBCM)2 significantly inhibited the growth of MDA-MB-231 cells in a dose-dependent manner with GI50 18.7 ± 3.06 µM. Indeed, Cu(SBCM)2 was less toxic towards HDF normal cells with GI50 31.8 ± 4.0 µM. Morphological study revealed that Cu(SBCM)2-treated MDA-MB-231 cells experienced cellular shrinkage, membrane blebbing, chromatin condensation and formation of apoptotic bodies, suggesting that Cu(SBCM)2 induced apoptosis in the cells, which was confirmed by Annexin-V/PI flow cytometry analysis. It was also found that Cu(SBCM)2 induced G2/M phase cell cycle arrest towards MDA-MB-231 cells. The induction of apoptosis and cell cycle arrest in the present study is possibly due to the down-regulation of the mutant p53 and MMP2 protein. In conclusion, Cu(SBCM)2 can be developed as a targeted therapy for the treatment of triple-negative breast cancer.
The p27 V109G polymorphism was investigated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in a hospital-based Malaysian population. Peripheral blood samples were collected from 230 breast cancer patients and 200 normal and healthy women who had no history of breast disease or breast cancer. We evaluated the association between the p27 polymorphism and breast cancer risk, and clinico-pathological parameters in the population. The distribution of genotype and allele frequencies of p27 V109G polymorphism were not significantly different between the breast cancer cases and normal subjects (P=0.376). Women who were homozygous (OR=1.73; 95% CI, 0.62-4.92) or heterozygous (OR=1.26; 95% CI, 0.75-2.12) for G allele, or carriers of G allele genotype (OR=1.34; 95%, 0.83-2.16) or G allele (OR=1.36; 95% CI, 0.90-2.05) were not associated with breast cancer risk. No significant correlation was noted between G allele genotype and breast cancer risk among patients under 50 (OR=1.28; 95% CI, 0.62-2.66) or 50 years and older (OR=1.38; 95% CI, 0.71-2.66) at diagnosis. The G allele genotype was significantly associated with lymph node metastases but independent of ER status and histological grade. In conclusion, the polymorphic variant at codon 109 of p27 gene may not be a marker for determining patients' risk of developing breast cancer but it may be a potential genetic marker for poor prognosis, thereby a marker for tumor prognosis.
Epidemiological studies have reported inconsistent findings for the association between B vitamins and breast cancer (BC) risk. We investigated the relationship between biomarkers of folate and vitamin B12 and the risk of BC in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Plasma concentrations of folate and vitamin B12 were determined in 2,491 BC cases individually matched to 2,521 controls among women who provided baseline blood samples. Multivariable logistic regression models were used to estimate odds ratios by quartiles of either plasma B vitamin. Subgroup analyses by menopausal status, hormone receptor status of breast tumors (estrogen receptor [ER], progesterone receptor [PR] and human epidermal growth factor receptor 2 [HER2]), alcohol intake and MTHFR polymorphisms (677C > T and 1298A > C) were also performed. Plasma levels of folate and vitamin B12 were not significantly associated with the overall risk of BC or by hormone receptor status. A marginally positive association was found between vitamin B12 status and BC risk in women consuming above the median level of alcohol (ORQ4-Q1 = 1.26; 95% CI 1.00-1.58; Ptrend = 0.05). Vitamin B12 status was also positively associated with BC risk in women with plasma folate levels below the median value (ORQ4-Q1 = 1.29; 95% CI 1.02-1.62; Ptrend = 0.03). Overall, folate and vitamin B12 status was not clearly associated with BC risk in this prospective cohort study. However, potential interactions between vitamin B12 and alcohol or folate on the risk of BC deserve further investigation.