Breast cancer pathology: The impact of molecular taxonomy on morphological taxonomy

Application of Immunohistochemistry in Clinical Practices as a Standardized Assay for Breast Cancer

Immunohistochemistry (IHC) has become an indispensable tool in the clinical practices for breast cancer; however, to achieve its standardization, numerous issues need to be overcome. In this review, we describe the development of IHC as an important clinical tool, and the challenges in standardizing IHC results for patients. We also present ideas for resolving the remaining issues and unmet needs, along with future directions.

Differential Expression and Prognostic Significance of STARD3 Gene in Breast Carcinoma

StAR related lipid transfer domain containing 3 (STARD3) gene has been reported to be co-amplified with human epidermal growth factor receptor 2 (HER2) in breast carcinoma. STARD3 is necessary for cholesterol transfer and metabolism in tumor cells. The possible role played by STARD3 as a diagnostic and prognostic biomarker was investigated in breast cancer (BC). Data mining was performed using several bioinformatics websites to investigate the correlation of STARD3 with BC and its molecular subtypes, and conventional PCR was used to detect the STARD3 mRNA levels in a panel of BC cell lines. STARD3 was overexpressed in BC more than the other types of cancer. The results also showed that STARD3 expression was significantly associated with HER2⁺ BC tumors and BC cell lines, and low STARD3 mRNA and protein expression levels were observed in estrogen receptor-positive (ER⁺) and triple-negative BC (TNBC) patients. Moreover, high STARD3 expression levels predicted worse overall survival (OS), relapse-free survival (RFS) and disease metastasis-free survival (DMFS) in BC, and HER2⁺ BC. Notably, low expression of STARD3 was associated with poor OS in ER⁺ BC. Our findings suggest that STARD3 may have strong diagnostic and prognostic value for HER2⁺ breast carcinoma.

Immunohistochemical Expression of Vimentin in Invasive Breast Carcinoma and Its Correlation with Clinicopathological Parameters

Introduction

Breast carcinoma (BCa) is one of the most common cancers among women globally. Increased vimentin expression has been reported in various epithelial cancers.

Aim

This study examines the expression of vimentin in BCa and its correlation with various prognostic factors such as tumor size, histological grade, lymph node status, estrogen receptor (ER), progesterone receptor (PR), HER2/neu, and Ki67 status.

Materials and Methods

Seventy cases of BCa diagnosed between 2014 and 2015 were included in the study. A technique of manual tissue microarray was employed for the analysis of expression of immunohistochemical (IHC) markers such as vimentin, ER, PR, HER2/neu, and Ki67. Results were subjected to statistical analysis.

Results

Vimentin was found positive in 53 (75.7%) cases of BCa, of which 18 cases (25.7%) were triple-negative BCa (TNBC). Positivity for ER, PR, Her2, and Ki67 was 32.8%, 31.4%, 60%, and 99%, respectively. Vimentin expression was significantly associated with ER negativity. All 53 cases expressing vimentin showed positive Ki67 labeling index; however, this was not statistically significant. Maximum vimentin expression was observed in the age group >50 years, postmenopausal women, BCa cases showing lymphovascular invasion (LVI), axillary lymph node metastasis, higher stage and higher grade of tumor, negative PR expression, and positive HER2/neu expression. However, this was not statistically significant. In TNBC, vimentin expression was significantly associated with histological grade and LVI.

Conclusion

Vimentin expression was associated with well-established poor prognostic factors of BCa. Vimentin expression if routinely included in histopathology report would aid in better understanding of tumor behavior.

Loss of p27kip1 expression is associated with poor prognosis in patients with taxane-treated breast cancer

PURPOSE

Decreased expression of p27^kip1 and p57^kip2 is considered as a prognostic indicator in patients with breast cancer receiving adjuvant chemotherapy. Previous in vitro studies have reported that reduced expression of p27^kip1 and p57^kip2 is associated with resistance to taxane, which is one of the most effective chemotherapeutic agents. In this study, we investigated the association of low p27^kip1 and p57^kip2 expression with outcomes in patients with breast cancer.

METHODS

We investigated 226 cases of breast cancer from Kangbuk SMC between 2000 and 2005. Levels of p27^kip1 and p57^kip2 expression were evaluated using immunohistochemical staining of tumor tissue microarray specimens. The relationships between the expression levels of the markers and patients' outcomes were analyzed using the Kaplan-Meier method and Cox proportional hazard model.

RESULTS

Low p57^kip2 expression was only associated with negative progesterone receptor status (p = 0.034), whereas p27^kip1 expression was associated with poor prognosis of patients receiving adjuvant chemotherapy (p = 0.005). More detailed analysis revealed that low p27^kip1 expression affects the overall survival rate of patients receiving adjuvant chemotherapy including taxane (p = 0.026), but not that of patients receiving chemotherapy without taxane.

CONCLUSIONS

Low p27^kip1 expression may be useful to predict overall survival in patients with breast cancer who are treated with taxane. Evaluation of p27^kip1 expression may provide further prognostic information beyond traditional prognostic biomarkers and an understanding of the mechanisms that impart resistance against chemotherapy.

Negative association between GATA3 and fascin could predict relapse-free and overall survival in patients with breast cancer

GATA3 and fascin proteins are known prognostic markers in several cancers. GATA3 is a key regulator of mammary gland morphogenesis and luminal cell differentiation, whereas fascin is a pro-metastatic actin-bundling protein. In this study, we analyzed and compared the predictive abilities of GATA3 and fascin for clinical outcomes of patients with breast cancer. The combined expression pattern based on GATA3-/+ and fascin-/+ was evaluated by immunostaining using a tissue microarray, and relationships between protein expression and several clinicopathological parameters were analyzed. GATA3 expression was associated with good prognostic parameters, but fascin was correlated with poor prognostic parameters. On comparing GATA3 and fascin, we found an inverse relationship between fascin and GATA3 expressions. On analysis of combined markers, GATA3+/fascin- was correlated with improved clinical outcomes compared to GATA3-/fascin+. Univariate and multivariate analyses revealed significant differences in relapse-free and overall survival between GATA3+/fascin- and GATA3-/fascin+. Combined marker analysis of GATA3/fascin showed an inverse association and improved prognostic information for patients with breast cancer.

Relation between parity and pregnancy-related hormones and breast cancer control

SUMMARY 

Epidemiological research has indicated the beneficial effects of full-term pregnancy at an early age for a reduction in breast cancer risk. Experimental data have shown that pregnancy and pregnancy-related hormones, such as estrogen plus progesterone, estrogen alone and human chorionic gonadotropin, are involved in parity-induced protection. Pregnancy and short-duration treatment of a young host with pregnancy-related hormones to mimic the pregnancy environment provide mammary cancer protection by making cells refractory to carcinogenic stimuli and causing growth arrest and programmed cell death. Experimental data concerning pregnancy and pregnancy-related hormones are reviewed in relation to intrinsic subtypes of mammary cancer.

Pathological examination of breast cancer biomarkers: current status in Japan

This article reviews the current status of pathological evaluation for biomarkers in Japan. The introduced issues are the international trends for estimation of biomarkers considering diagnosis and treatment decision, and pathological issues under discussion, and how Japanese Breast Cancer Society (JBCS) members have addressed issues related to pathology and biomarkers evaluation. As topics of immunohistochemical study, (1) ASCO/CAP guidelines, (2) Ki67 and other markers, (3) quantification and image analysis, (4) application of cytologic samples, (5) pre-analytical process, and (6) Japan Pathology Quality Assurance System are introduced. Various phases of concepts, guidelines, and methodologies are co-existed in today's clinical practice. It is expected in near future that conventional methods and molecular procedures will be emerged, and Japanese Quality assurance/Quality control (QA/QC) system will work practically. What we have to do in the next generation are to validate novel procedures, to evaluate the relationship between traditional concepts and newly proposed ideas, to establish a well organized QA/QC system, and to standardize pre-analytical process that are the basis of all procedures using pathological tissues.

The sulfatase pathway for estrogen formation: targets for the treatment and diagnosis of hormone-associated tumors

The extragonadal synthesis of biological active steroid hormones from their inactive precursors in target tissues is named "intracrinology." Of particular importance for the progression of estrogen-dependent cancers is the in situ formation of the biological most active estrogen, 17beta-estradiol (E2). In cancer cells, conversion of inactive steroid hormone precursors to E2 is accomplished from inactive, sulfated estrogens in the "sulfatase pathway" and from androgens in the "aromatase pathway." Here, we provide an overview about expression and function of enzymes of the "sulfatase pathway," particularly steroid sulfatase (STS) that activates estrogens and estrogen sulfotransferase (SULT1E1) that converts active estrone (E1) and other estrogens to their inactive sulfates. High expression of STS and low expression of SULT1E1 will increase levels of active estrogens in malignant tumor cells leading to the stimulation of cell proliferation and cancer progression. Therefore, blocking the "sulfatase pathway" by STS inhibitors may offer an attractive strategy to reduce levels of active estrogens. STS inhibitors either applied in combination with aromatase inhibitors or as novel, dual aromatase-steroid sulfatase inhibiting drugs are currently under investigation. Furthermore, STS inhibitors are also suitable as enzyme-based cancer imaging agents applied in the biomedical imaging technique positron emission tomography (PET) for cancer diagnosis.

Pathological and epidemiological factors associated with advanced stage at diagnosis of breast cancer

BACKGROUND

Breast cancer is a highly heterogeneous disease, but the stage at presentation significantly influences outcome. It is important to dissect the pathobiological and epidemiological factors that influence the stage at presentation in order to develop effective strategies to improve clinical outcome.

SOURCES OF DATA

PubMed references relating to breast cancer subtypes, molecular classification of breast cancer, genetic susceptibility, young women and breast cancer.

AREAS OF AGREEMENT

HER-2 positive, basal-like tumours and inflammatory breast cancers (IBC) more frequently present as late stage disease. Socioeconomic, cultural and ethnic background also influence stage at presentation.

AREAS OF CONTROVERSY

The biology of IBC is poorly understood. Relative contribution of social and genetic factors in certain ethnic groups. GROWING POINTS Molecular determinants of breast cancer behaviour. Genetic and biological factors influencing disease phenotype in different ethnic groups.

AREAS TIMELY FOR DEVELOPING RESEARCH

Biology of basal-like tumours and IBC. Role of predisposition of genetic variants in determining breast cancer phenotypes. Biological differences in breast cancer from different ethnic groups.