Expression In Breast Carcinoma Research Articles

Abstract 991: OVO-like genes are master regulators of the epithelial fate in breast cancer

Abstract The OVO-like genes are evolutionary conserved C2H2 zinc finger transcription factors (TFs) with SNAG repressor domains involved in the maintenance of epithelial homeostasis. From the three Ovo-like family genes identified in mammals, Ovol-like1 (Ovol1) and Ovol-like2 (Ovol2) are the most studied members with multiple reports pinpointing relevant roles in development and disease. In cancer, one of the hallmarks of invasive carcinoma involves the loss of E-cadherin expression by the repression of SNAG transcription factors. Interestingly, contrary to the other SNAG domain family members the OVO-like genes regulate epithelial cell fate. We performed data analysis in breast cancer cell lines and patient data obtained from GEO, CCLE, TCGA and METABRIC to assess the potential of the OVO-like genes as relevant regulators of gene expression in breast carcinoma. In addition, we stablished breast cancer models with inducible expression or repression of the OVO-like genes. We also analyzed the cellular systems we generated using naïve high-throughput methods such as RNA-Seq. Likewise, we studied the effect of OVO-like genes on tumor progression and metastasis using inducible expression systems in both xenograft and syngeneic breast cancer models. We observed that Ovol1 and Ovol2 are constitutively expressed in human breast cancer cell lines, and they are upregulated due to chromosomal gains in breast cancer patients. We observed how the introduction of Ovol1 and Ovol2 into mesenchymal-like breast cancer cell lines modified their transcriptome in a way that promoted expression of epithelial marker genes (e.g., Amphiregulin) and downregulated mesenchymal markers (e.g., Vimentin). In addition, introducing Ovo-like genes in mesenchymal-like cells greatly affected their viability and function. Surprisingly, we observed a similar effect by downregulating the Ovo-like genes in epithelial-like cells. We propose a model where a common epigenetic machinery is shared between structurally related transcription factors with opposing effects, such as OVO-like proteins and other SNAG-containing transcription factors, such as Snail and Slug, such that the abundance of the transcription factors and their co-repressors defines the state of the system as either epithelial or mesenchymal. Citation Format: Diana Drago Garcia, Yosef Yarden. OVO-like genes are master regulators of the epithelial fate in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 991.

Expression of novel neuroendocrine markers in breast carcinomas: a study of INSM1, ASCL1, and POU2F3

INSM1, ASCL1, and POU2F3 are novel transcription factors involved in neuroendocrine (NE) differentiation of neoplasms in several organs, but data on their expression in breast carcinomas (BCs) are limited. We retrospectively evaluated the expression of these markers in a series of 97 BCs (58 with NE morphology and 39 with otherwise uncommon morphology) tested prospectively using immunohistochemistry (IHC). Nuclear staining in >50% of the cells was used as the positive cut-off. Thirty-two of the 97 BCs (33%) were INSM1-positive. INSM1-positivity correlated significantly with histologic type and presence of stromal mucin. INSM1 also correlated with synaptophysin and chromogranin, established markers of NE differentiation (P<.0001 and P=.0023, respectively). In BC with NE morphology, the expression of INSM1 supported NE differentiation, and INSM1 was more specific than synaptophysin and more sensitive and specific than chromogranin. INSM1 was the most expressed NE marker in 17BCs. INSM1-positive BCs included 56% of solid papillary BCs, 88% of BCs with solid papillary features, and 75% of high-grade NE carcinomas. Of 35 BCs tested for POU2F3 and ASCL1, only 1 and 4 cases were positive, respectively. Our results show that INSM1 is a sensitive marker of NE differentiation in BC and should be included with synaptophysin and chromogranin in the IHC panel used to evaluate NE differentiation in BC with NE morphology. ASCL1 and POU2F3 are uncommon in BC and their routine assessment is not warranted.

MTHFD2 Expression Profile and Its Prognostic Importance in Invasive Breast Carcinoma

Background: Breast cancer is the most common cancer among women. Therefore, it is very important to determine prognostic parameters and biomarkers related to these parameters. Recent studies have shown that folate metabolism is effective on cell division and invasiveness. One of the most important regulators of folate metabolism is the methylene tetrahydrofolate dehydrogenase enzyme (MTHFD2). Method: This study, immunohistochemical staining with MTHFD2 was performed in 194 cases diagnosed with invasive breast carcinoma. The relationship between the immunohistochemical expression of MTHFD2 in normal ductal areas and invasive tumoral areas of these cases and some clinicopathological parameters was investigated. Results: While no expression was observed in non-tumor areas with MTHFD2, varying degrees of expression were observed in all tumor areas (p&lt;0.0001). Significant correlations were also observed between important clinicopathological and prognostic parameters such as MTHFD2 nuclear grade, hormonal receptor, Ki67 and etc. (all p&lt;0.05). Conclusion: High MTHFD2 expression in breast carcinomas with invasive and poor prognostic values ​​was determined to be very significant. Therefore, it can be predicted that detecting and lowering MTHFD2 levels in these cases may prevent tumor development, invasion and metastasis. We think that more studies on the subject are needed, including the development of chemotherapeutics targeting MTHFD2.

The Valuable Role of ARMC1 in Invasive Breast Cancer as a Novel Biomarker.

Background Invasive breast carcinoma (BRCA) is a common type of breast cancer with a high clinical incidence. Thus, it is significant to find effective biomarkers for BRCA diagnosis and treatment. Although some members of armadillo (ARM) repeat family of proteins are confirmed to be biomarkers in cancers, the role of armadillo repeat-containing 1 (ARMC1) in BRCA remains unknown. Methods We firstly analyzed the ARMC1 expression in normal breast tissues and BRCA samples and its association with overall survival by the public database. Next, the χ2 test was used to evaluate the prognostic significance of ARMC1 expression in TCGA-BRCA patient samples. The ARMC1 mutations in BRCA were explored in the cBioportal database. Besides, the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to explore the biological functions of ARMC1 in BRCA. Finally, immunohistochemistry and immunofluorescence staining were performed to validate the ARMC1 expression in BRCA. Results ARMC1 expression in tumor samples was significantly higher than that in normal tissues, and higher expression of ARMC1 was related to lower survival. Moreover, the tumor stage and histology of BRCA patients were associated with ARMC1 expression. ARMC1 genetic mutations occurred in 32% of BRCA patients, and the amplification and high expression of ARMC1 accounted for most of them. Furthermore, functional enrichment analysis suggested that ARMC1 might be involved in the cell cycle in BRCA. Ultimately, increased ARMC1 expression was found in clinical breast carcinoma tissues by our confirmatory experiments. Conclusions ARMC1 may play a significant role in BRCA and act as a biomarker, which provides valuable clues for the treatment and diagnosis of BRCA.

Prognostic value of programmed death ligand-1 expression in breast carcinomas

ObjectivesTo assess the prognostic value of programmed death ligand-1 (PDL-1) expression in patients with nonmetastatic breast carcinoma patients both in tumor cells and tumor-infiltrating lymphocytes (TILs).BackgroundPDL-1 has emerged as important immune biomarkers in breast cancer. It can be targeted with immunotherapy, which represents a significant advancement in the management of this disease.Patients and methodsParaffin blocks of patients with breast cancer will be tested for the expression of PDL-1 both on TILs and malignant epithelial cells and correlated with patients and disease features.ResultsThis retrospective study included 60 patients. PDL-1 expression was positive in 33 (55%) patients on TILs and was positive in tumor cells in 27 (45%) patients of the studied patients. There was no significant relation between PDL-1 expression on TILs and patients and disease features. There was significant relation between positive PDL-1 expression on epithelial cells and triple-negative breast cancer, estrogen receptor negative, progesterone receptor negative status (P = 0.006, 0.006, and 0.006). PDL-1 intensity in intratumoral lymphocytes is significantly related to tumor stage (P = 0.006). PDL-1 H score in malignant epithelial cells was significantly related to disease stage (P = 0.021). Tumor size, HER-2neu status, and PDL-1 H score on malignant epithelial cells were independent risk factors for disease progression.ConclusionPDL-1 expression is common in both malignant tumor cells and TILs. A higher PDL-1 H score on malignant epithelial cells was associated with longer time to progression.

TRPS1 Expression in Breast Carcinomas: Focusing on Metaplastic Breast Carcinomas.

TRPS1 has been recently demonstrated as a highly sensitive and specific marker for breast carcinomas. To further explore TRPS1's utility in breast carcinoma, we systematically evaluated TRPS1 expression on tissue microarrays from 160 estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-positive, 94 ER-/HER2+, 117 triple-negative breast carcinomas, and 618 other primary carcinomas (cholangiocarcinoma, endometrial, colorectal, and hepatocellular carcinomas), and whole tissue sections from 64 HER2+, 76 triple-negative, and 67 metaplastic breast carcinomas. The results showed TRPS1 was highly expressed in breast carcinomas (100% of HER2+ and 97.4% of triple negative on whole tissue sections), but almost completely negative in other tested tumor types. TRPS1 was also highly expressed in metaplastic carcinoma (91%), significantly higher than GATA3 (55.2%). The different expression between TRPS1 and GATA3 was most prominent in chondroid/mesenchymal subtypes (100% vs. 36.4%), followed by spindle cell carcinoma (66.7% vs. 44.4%). In addition, TRPS1 was expressed in normal breast ductal epithelial cells with less staining than in carcinoma cells, and TRPS1 showed aberrant membranous staining in HER2+ breast carcinomas that suggests a potential cross-reactivity with HER2 protein.

E2F1 and epigenetic modifiers orchestrate breast cancer progression by regulating oxygen-dependent ESRP1 expression

Epithelial splicing regulatory protein 1 (ESRP1) is an RNA binding protein that governs the alternative splicing events related to epithelial phenotypes. ESRP1 contributes significantly at different stages of cancer progression. ESRP1 expression is substantially elevated in carcinoma in situ compared to the normal epithelium, whereas it is drastically ablated in cancer cells within hypoxic niches, which promotes epithelial to mesenchymal transition (EMT). Although a considerable body of research sought to understand the EMT-associated ESRP1 downregulation, the regulatory mechanisms underlying ESRP1 upregulation in primary tumors remained largely uncharted. This study seeks to unveil the regulatory mechanisms that spatiotemporally fine-tune the ESRP1 expression during breast carcinogenesis. Our results reveal that an elevated expression of transcription factor E2F1 and increased CpG hydroxymethylation of the E2F1 binding motif conjointly induce ESRP1 expression in breast carcinoma. However, E2F1 fails to upregulate ESRP1 despite its abundance in oxygen-deprived breast cancer cells. Mechanistically, impelled by the hypoxia-driven reduction of tet methylcytosine dioxygenase 3 (TET3) activity, CpG sites across the E2F1 binding motif lose the hydroxymethylation marks while gaining the de novo methyltransferase-elicited methylation marks. These two oxygen-sensitive epigenetic events work in concert to repel E2F1 from the ESRP1 promoter, thereby diminishing ESRP1 expression under hypoxia. Furthermore, E2F1 skews the cancer spliceome by upregulating splicing factor SRSF7 in hypoxic breast cancer cells. Our findings provide previously unreported mechanistic insights into the plastic nature of ESRP1 expression and insinuate important implications in therapeutics targeting breast cancer progression.

Dual inhibition of MEK1/2 and MEK5 suppresses the EMT/migration axis in triple-negative breast cancer through FRA-1 regulation.

Triple-negative breast cancer (TNBC) presents a clinical challenge due to the aggressive nature of the disease and a lack of targeted therapies. Constitutive activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway has been linked to chemoresistance and metastatic progression through distinct mechanisms, including activation of epithelial-to-mesenchymal transition (EMT) when cells adopt a motile and invasive phenotype through loss of epithelial markers (CDH1), and acquisition of mesenchymal markers (VIM, CDH2). AlthoughMAPK/ERK1/2 kinase inhibitors (MEKi) are useful antitumor agents in a clinical setting, including the Food and Drug Administration(FDA)-approved MEK1,2 dual inhibitors cobimetinib and trametinib, there are limitations to their clinical utility, primarily adaptation of the BRAF pathway and ocular toxicities. The MEK5 (HGNC: MAP2K5) pathway has important roles in metastatic progression of various cancer types, including those of the prostate, colon, bone and breast, and elevated levels of ERK5 expression in breast carcinomas are linked to a worse prognoses in TNBC patients. The purpose of this study is to explore MEK5 regulation of the EMT axis and to evaluate a novel pan-MEK inhibitor on clinically aggressive TNBC cells.Our results show a distinction between the MEK1/2 and MEK5 cascades in maintenance of the mesenchymal phenotype, suggesting that the MEK5 pathway may be necessary and sufficient in EMT regulation while MEK1/2 signaling further sustains the mesenchymal state of TNBC cells. Furthermore, additive effects on MET induction are evident through the inhibition of both MEK1/2 and MEK5. Taken together, these data demonstrate the need for a better understanding of the individual roles of MEK1/2 and MEK5 signaling in breast cancer and provide a rationale for the combined targeting of these pathways to circumvent compensatory signaling and subsequent therapeutic resistance.

Higher CD1a Levels Correlate with PD-L1 Expression and Predict Worse Overall Survival in Triple-Negative Breast Carcinoma

Objective: The aim of this study was to measure the expression of PD-L1, CD1a (a marker for immature dendritic cells), and CD83 (a marker for mature dendritic cells) and further examine the associations of PD-L1, CD83, and CD1a with overall survival (OS) in triple-negative breast carcinoma patients. Methods: PD-L1, CD1a, and CD83 expression in breast carcinoma tissues and CD83 expression in lymph node tissues were examined by immunohistochemistry and tissue microarray in 159 patients. Patients were classified into the low, medium, and high PD-L1, CD1a, and CD83 levels. Pearson χ² test was used to analyze the correlations between PD-L1, CD1a, and CD83. The Kaplan-Meier method was used to calculate the OS. Multivariate analysis was used to identify determinants of 3- and 5-year OS. Results: 25.1, 25.8, and 49.1% of the patients had low, medium, and high PD-L1 levels, respectively. PD-L1 levels significantly correlated with CD1a (r = 0.30409, p < 0.001) and CD83 levels (r = 0.6146, p < 0.001) in breast carcinoma tissue, as well as CD83 levels (r = 0.17508, p = 0.027) in lymph node. The median OS was 83 months (range 12–106), and the 3- and 5-year OS rates were 94.97% (95% CI 91.57–98.37) and 86.79% (95% CI 81.53–92.06), respectively. Moreover, patients with high median CD1a levels had a significantly lower 5-year OS rate (75.6%) than those with low median CD1a levels (93.5%, p = 0.038). Conclusion: PD-L1, CD1a, and CD83 are variably expressed in triple-negative breast carcinoma tissues, and PD-L1 expression correlates with CD1a and CD83. Higher CD1a levels correlate with PD-L1 expression and predict worse OS in triple-negative breast carcinoma.

Matrix Metalloproteinase-2 Expression as a Prognostic Marker in Breast Carcinomas

Introduction: Matrix Metalloproteinase-2 (MMP-2) is over expressed in a variety of malignant tumours and their expression and activity are often associated with tumour aggressiveness and a poor prognosis. It serves as a prognostic marker in breast carcinoma regardless of patient age, disease stage, malignancy grade, or hormone receptor status and modulation of MMP-2 expression and activation provides a new mechanism for breast cancer treatment. Aim: To evaluate the expression of MMP-2 in breast carcinoma tumour cells and peritumoural stroma and also to analyse the findings with the existing other prognostic markers of mammary carcinoma. Materials and Methods: The present study was a retrospective study conducted on paraffin blocks of 90 cases of invasive breast carcinoma specimens received in the Department of Pathology, Sri Raamachandra Institute of Higher Education and Research a tertiary care centre in Chennai, Tamil Nadu, India, from January 2012 to June 2017. Immunohistochemical staining for MMP-2, Oestrogen Receptor (ER), Progesterone Receptor (PR) and Human Epidermal Growth Factor Receptor 2 (HER2) was done. Statistical analysis was done on the data collected by using the software GNU-PSPP version 0.10.1. Pearson Chi-square test was used to determine significant clinicopathological differences between MMP-2 expression in positive and negative tumours. Differences were considered statistically significant when p-value was &lt;0.05. Results: The study included 90 cases of histological proven invasive breast carcinoma. The study parameters include age, clinical staging, histopathological grade, lymphnode status, molecular subtype and MMP-2 expression in invasive breast carcinoma. Out of 90 cases, 62 cases were positive for MMP-2 and 18 cases were positive for peritumoural stroma, 30 cases were negative for MMP-2 in tumoural cells and 72 cases were negative surrounding the peritumoural stroma. Conclusion:Present study showed high MMP-2 immunohistochemical expression in breast carcinomas. There was a statistically significant association of increased MMP-2 expression with tumour stage. There was also a statistically significant association of MMP-2 in the tumour and stroma with High Grade Ductal Carcinoma In Situ (HGDCIS). There was an increased expression of MMP-2 in Luminal A subtype. Low expression was seen in the other molecular subtypes. In view of these findings and association with other studies in the literature, the present study demonstrates that the expression of MMP-2 in tumour and stromal cells could serve as a parameter of poor prognosis in breast cancer.

Insulinoma-associated protein 1 (INSM1) expression in breast carcinomas with neuroendocrine morphologies: application and future prospective.

Herein, we describe the first cases of neuroendocrine (NE) phenotype mammary carcinomas in which the NE nature of the tumors was confirmed only by insulinoma-associated protein 1 (INSM1), without expressions of traditional "gold standard" NE indicators. This is also the first analysis to use INSM1, a promising antibody with high sensitivity and specificity, in the field of breast oncology. Three patients were, respectively, 42-, 58-, and 64-year-old Japanese women with breast tumors showing characteristic NE morphologies. Immunohistochemically, these malignancies revealed diffuse nuclear expressions of INSM1, whereas chromogranin A and synaptophysin did not show distinct NE features in their cytoplasm. Based on the identification of INSM1 as well as our present immunohistochemical results, the frequency of detecting NE differentiation in systemic neoplasms, including breast NE phenotype cancers, is anticipated to increase such that, ultimately, our observations might contribute to the development of novel treatments including molecular targeted drugs for these tumor entities.

Estrogen and Progesterone Receptor Expression in Breast Carcinoma and Its Association With Clinicopathological Variables Among the Pakistani Population.

IntroductionThe prognosis of breast cancer depends on the histological type, size of the tumor, tumor necrosis, skin, nipple and chest wall invasion, lymphovascular invasion, grade, stage, the status of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2), cell proliferation marker (ki-67), and type of therapy. Estrogen receptor and progesterone receptor expression in breast cancer is, so far, the most useful predictive marker. We have undertaken this study to find the expression of ER and PgR in breast carcinoma and its association with other prognostically important clinicopathological variables.Materials and methodsIn this cross-sectional study, a total of 130 cases of modified radical mastectomy that have been diagnosed as malignant on histopathology were collected from the pathology department of Allama Iqbal Medical College, Lahore, from January 2016 to May 2018. The demographic data and gross and microscopic findings were recorded. Immunohistochemistry (ER, PgR) was applied to suitable tumor sections and their status was evaluated semi-quantitatively by histopathologists using College American Pathologist (CAP) guidelines.ResultMost of the breast cancer patients (69; 53.1%) were below 50 years of age. Fifty-nine (45.4%) and 48 (36.9%) cases were positive for ER and PgR, respectively, showing lower hormonal receptor positivity than that reported in the western population where ER expression has been found in 50%-80% of cases and PR expression is found in 60%-70% of cases of invasive ductal carcinoma. The association of the expression of hormone receptors with a clinicopathological variable was demonstrated. ER-/PgR- tumors showed a higher histologic grade, greater tumor size, and more lymph node involvement by metastasis.ConclusionLow hormone receptor positivity is associated with young patients, advanced stage at presentation, and higher grade in our population. The tumor characteristics are different as compared to the western population. This suggests more consideration to the screening, early diagnosis, and molecular or immunohistochemical typing of this cancer in our population.

EMMPIRRIN(CD147) and matrix matrix metalloproteinase-9 (MMP9) immunohistochemical expression in breast carcinoma: relationship with clinicopathological paremeters

Background: Breast cancer is one of the leading causes of cancer mortality in women worldwide. Despite significant advances in cancer treatment, mortality results from local invasion and/or distant metastasis. Aim: To evaluate EMMPIRIN (CD147) and matrix metalloproteinase-9 (MMP9) immunohistochemical expressions significance in invasive ductal breast carcinoma cases in relation to other clinicopathological parameters. Materials and Methods: The study included 50 specimens of surgically resected breast carcinomas in which the expression of CD147and MMP9 was assessed. The results were compared statistically with chi-square (χ2) and Fisher exact test. Results: CD174 overexpression showed significant association with poorly differentiated tumors, staging, presence of nodal metastasis and high Ki67 expression. There was a significant correlation between high MMP9 expression and pathological variables as tumor staging, positive nodal metastasis, low ER expression and high HER2 expression. Conclusion: The results of this study suggest that high expressions of EMMPRIN and MMP9 correlate to poor prognostic parameters. Targeted therapy might improve the prognosis of patients with CD147 and MMP-9 overexpression.

Relationship between Calcification on Mammography and Human Epidermal Growth Factor Receptor 2 (HER-2) Expression in Breast Carcinoma

Background : Breast carcinoma shows over-expression of Human Epidermal Growth Factor Receptor 2 (HER-2) in 18 to 20% of the cases. This type of cancer is very progressive and has a poor prognosis. This study aimed to determine the association between the calcification on mammography with HER-2 expression in breast carcinoma as a marker of breast carcinoma aggressiveness. Methods : This was an analytic observational study with a case-control design. Patients with breast carcinoma at the Department of Radiology and Department of Anatomical Pathology of Dr. Hasan Sadikin General Hospital Bandung from July–September 2019 were enrolled in this study. Samples were consecutively collected. The association of calcification on mammography and HER2 expression was analyzed using the Chi-square test. Result : In total, 40 patients were included, consisting of 20 individuals with HER-2 positive and 20 individuals with HER-2 negative. The youngest was 40 years old and the oldest was 73 years old. Statistical test results showed that there was a significant association between calcifications in mammography and HER-2 expression (p-value = 0.0001, OR 13.22; 95% CI 2.7–62.6). Conclusions : There is a significant association between calcification on mammography and HER-2 expression in breast carcinoma, suggesting that positive calcification mammography was 13.22 times higher in patients with HER-2 positive compared to patients with negative calcifications.

Association between low estrogen receptor positive breast cancer and staining performance

Estrogen receptor (ER) expression in breast carcinomas, determined by immunohistochemistry, indicates statistically significant benefit to endocrine therapy in patients with tumors expressing ER in ≥1% of tumor cells. Rare cases with low ER expression (1–10%) lead to the dilemma of treating these tumors as ER positive or negative. We hypothesize that low ER positive result from poor staining performance and that we may detect this artefact by assessing the average dynamic range of normal ducts adjacent to low ER positive tumors. Using quantitative tools, we compare the dynamic range of normal background ER expression in patients with low (1–10%) ER tumors to dynamic range of ER expression in normal epithelium from control patient populations, to determine if low ER cases are accompanied by decreased dynamic range. Low ER cases were infrequent (1% of invasive breast carcinomas). Twenty-one cases with low ER staining and two control cohorts, including a tissue microarray (TMA) of 10 benign breast sections and a group of 34 control breast carcinomas (reported as ER negative or >10% ER positive) with normal background epithelium, were digitally scanned. QuPath was utilized to quantify ER staining for each cell as the mean optical density of nuclear DAB staining. The dynamic range of ER expression in normal epithelium surrounding low ER tumors was significantly lower (range 2–240, median 16.5) than that of the benign epithelium in the control tumors (range 3–475, median 30.8; p < 0.001) and benign TMA sections (range 38–212, median 114; p < 0.001) suggesting inconsistent stainer performance.

Promoter Methylation Down-regulates B-cell Translocation Gene 1 Expression in Breast Carcinoma

The mechanism responsible for B-cell translocation gene 1 (BTG1) down-regulation in breast carcinoma remains unknown. We examined the BTG1 expression status in breast carcinoma cells and investigated the mechanism underlying the observed alterations. Four breast carcinoma cell lines (SK-BR-3, MDA-MB-231, T-47D, and MCF-7), and one normal mammary epithelial cell line (MCF-10A) were analyzed. BTG1 expression was examined using quantitative reverse transcription polymerase chain reaction (PCR) and western blot. Methylation status of the BTG1 promoter was analyzed using methylation-specific PCR (MSP). To investigate the effect of methylation on BTG1, the cells were treated with a demethylating agent. The carcinoma cells expressed significantly lower levels of BTG1 mRNA and protein than normal cells. The BTG1 promoter was highly methylated in the carcinoma cells. 5-aza-2-deoxycytidine significantly restored BTG1 expression. Down-regulation of BTG1 expression through epigenetic repression is involved in mammary carcinogenesis. BTG1 is a potential diagnostic marker and therapeutic target for breast carcinoma.

CD10 expression by stromal cells in carcinoma of breast and its correlation with ER, PR, HER2neu and Ki67-A tissue microarray study in a tertiary care hospital

Introduction: CD10 is a metalloproteinase (Zinc dependent) which is expressed in stroma of various epithelial malignancies. It is associated with biological aggressiveness of the tumor. Till now very few studies has been undertaken correlating CD10 with other prognostic markers like lymphnode status, tumor grade, stage, ER, PR, HER2-neu and ki67 in breast carcinoma. Aim: To see the CD10 expression in breast carcinoma and correlate it with ER, PR, HER2 neu and ki67. Materials and Methods: 55 cases of carcinoma breast were diagnosed on histology. Tissue microarray blocks were prepared and Immunohistochemistry was performed for ER, PR, HER2neu, Ki67 and CD10. Result: 32(58%) cases are CD10 positive and 23 (42%) cases are CD10 negative. Out of this 32 positive cases, 12 (22%) cases are weak positive and 20 (36%) cases are strong positive. CD10 is positively correlated with tumor grade.CD10 is negatively correlated with ER and PR status which is not statistically significant and no correlation is found between CD10 and HER2-neu. A positive correlation is seen between CD10 and ki67, but it is not statistically significant. Conclusion: CD10 expression is positively correlated with Ki67 and increasing tumor grade and whereas inversely correlated with ER and PR status. No correlation is seen between CD10 with lymph node status and HER2-neu. Keywords: Breast carcinoma, Histomorphology, IHC, Tissue microarray.

Comparison of PAX8 Expression in Breast Carcinoma Using MRQ50 and BC12 Monoclonal Antibodies.

PAX8 is a specific marker for kidney, ovarian, and thyroid tissue. Antibody-dependent cross-reactivity for PAX8 has been reported in mesothelial, pancreatic, and B-cell proliferations. We recently described antibody clone-dependent aberrant PAX8 expression in breast cancer. In this study we systematically analyze PAX8 expression in breast cancer on whole tissue sections, using MRQ50 and BC12 PAX8 monoclonal antibodies. Immunohistochemistry was performed on formalin-fixed paraffin-embedded whole tissue sections from 85 invasive mammary carcinomas. Immunostaining was evaluated at ×10 objective; extent (intervals of 10%, 0% to 100%) and intensity (weak, moderate, and strong) of nuclear staining was evaluated in the tumor, benign breast tissue, and lymphocytes. With MRQ50 variable PAX8 nuclear positivity was identified in tumor cells in 35/85 (41%) cases. Of 35 PAX8 cases, 23 (66%) showed only weak expression in 1% to 10% cells, 8 (23%) were weakly (5/8) or moderately (3/8) PAX8 in 11% to 50% cells, and 4 (11%) showed weak PAX8 positivity in >50% tumor cells. All 3 (3.5%) cases that showed moderate nuclear PAX8 staining with MRQ50 were histologic grade 3. No PAX8 expression was noted in benign lobules/ducts with either antibody. Breast carcinomas can show nuclear immunostaining with MRQ50 PAX8 antibody with up to 3.5% cases showing moderately intense expression. The BC12 PAX8 antibody does not cross-react with breast carcinoma and lymphocytes. During workup of metastatic carcinoma, weak to moderate PAX8 nuclear expression with MRQ50 clone should be interpreted with caution.

Nicotinamide N-methyltransferase enhances chemoresistance in breast cancer through SIRT1 protein stabilization

BackgroundNicotinamide N-methyltransferase (NNMT) is overexpressed in various human tumors and involved in the development and progression of several carcinomas. In breast cancer, NNMT was found to be overexpressed in several cell lines. However, the clinical relevance of NNMT in breast cancer is not yet clear.MethodsNNMT expression in breast carcinoma was examined by immunohistochemistry, and then, its relationship with patient clinicopathological characteristics was analyzed. The effects of NNMT on chemoresistance in breast cancer cells were assessed by cell viability, colony formation, and apoptosis assay. The NNMT, SIRT1, p53, and acetyl-p53 proteins, which are involved in NNMT-related chemoresistance, were examined by Western blotting. The SIRT1 mRNA was examined by real-time PCR, and its activity was measured by using the SIRT1 deacetylase fluorometric reagent kit.ResultsNNMT expression was significantly higher (53.9%) in breast carcinoma than in paracancerous tissues (10.0%) and breast hyperplasia (13.3%). A high level of NNMT expression correlated with poor survival and chemotherapy response in breast cancer patients who received chemotherapy. Ectopic overexpression of NNMT significantly inhibited the apoptotic cell death and suppression of colony formation induced by adriamycin and paclitaxel. Mechanistic studies revealed that NNMT overexpression increased SIRT1 expression and promoted its activity. Either inhibition of SIRT1 by EX527 or knockdown of SIRT1 by siRNA could reverse NNMT-mediated resistance to adriamycin and paclitaxel, which suggests that SIRT1 plays a critical role in NNMT-related chemoresistance in breast cancer.ConclusionsThe results of this study demonstrate a novel correlation between the NNMT expression level and patient survival, suggesting that NNMT has the potential to become a new prognostic biomarker to predict the treatment outcomes of the clinical chemotherapy in breast cancer. Moreover, targeting NNMT or downstream SIRT1 may represent a new therapeutic approach to improve the efficacy of breast cancer chemotherapy.

Ghrelin expression in breast carcinomas

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