Progesterone Receptor Antibodies Research Articles

Immunohistochemical Expression of ROS1 in invasive ductal carcinoma of breast in association with hormonal receptor status and Her2Neu expression

Objective: To determine the frequency of immunohistochemical expression of ROS1 in invasive ductal carcinoma of the breast in relation to hormonal receptor status and HER2 expression. Study Design and Setting: Descriptive cross-sectional study. Department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi from May 2022 to Dec 2022. Methodology: This study was conducted on a sample size comprising 137 patients diagnosed with invasive breast carcinoma (ductal carcinoma) on histopathological biopsy specimen. Immunohistochemistry was performed using ROS1, estrogen receptor, progesterone receptor and HER2 antibodies on patients’ tissue samples. Results were interpreted by two independent histopathologists. Finally data was analyzed using SPSS version 25. Results: The mean age of sample population was 50.85 ± 12.17 years. 131 patients were women and 6 were men. ROS1 was positive in 54 cases. ROS1 shows weak staining in 41 cases and moderate to strong staining in 13 cases. ER and PR showed no significant statistical correlation with ROS1 expression. HER2 was positive in 37 cases, equivocal in 11 cases and negative in 89 cases. A significant statistical correlation was seen between ROS1 and HER2 as 23 of HER2 positive cases showed ROS1 expression (p=<0.001). Conclusion: Significant number of ROS1 expressing cases in invasive breast carcinoma can be more revealing in the understanding of pathogenesis of breast carcinoma. In addition, it can also lead to use of certain recent tyrosine kinase inhibitors for treatment of this most common carcinoma in females.

Validation of a new Custom Polyclonal Progesterone Receptor Antibody for Immunohistochemistry in the Female Mouse Brain.

Immunohistochemical visualization of progesterone receptor (PR)-expressing cells in the brain is a powerful technique to investigate the role of progesterone in the neuroendocrine regulation of fertility. A major obstacle to the immunohistochemical visualization of progesterone-sensitive cells in the rodent brain has been the discontinuation of the commercially produced A0098 rabbit polyclonal PR antibody by DAKO. To address the unavailability of this widely used PR antibody, we optimized and evaluated 4 alternative commercial PR antibodies and found that each lacked the specificity and/or sensitivity to immunohistochemically label PR-expressing cells in paraformaldehyde-fixed female mouse brain sections. As a result, we developed and validated a new custom RC269 PR antibody, directed against the same 533-547 amino acid sequence of the human PR as the discontinued A0098 DAKO PR antibody. Immunohistochemical application of the RC269 PR antibody on paraformaldehyde-fixed mouse brain sections resulted in nuclear PR labeling that was highly distinguishable from background, specific to its antigen, highly regulated by estradiol, matched the known distribution of PR protein expression in the female mouse hypothalamus, and nearly identical to that of the discontinued A0098 DAKO PR antibody. In summary, the RC269 PR antibody is a specific and sensitive antibody to immunohistochemically visualize PR-expressing cells in the mouse brain.

Studies on a widely-recognized snail model species (Lymnaea stagnalis) provide further evidence that vertebrate steroids do not have a hormonal role in the reproduction of mollusks.

Experiments were carried out to determine whether, as with other mollusks that have been studied, the snail, Lymnaea stagnalis, can absorb, esterify and store vertebrate steroids that are present in the water. We also carried out experiments to determine whether neural tissues of the snail could be immunohistochemically stained with an antibody to human aromatase (a key enzyme that catalyzes the conversion of testosterone [T] to 17β-estradiol [E2]); and, if so, to determine the significance of such staining. Previous studies on other mollusks have reported such staining and have proposed this as decisive evidence that mollusks have the same steroid synthesis pathway as vertebrates. We found that snails absorb, esterify and retain esterified T, E2, progesterone and ethinyl-estradiol (albeit with an absorption rate about four times slower, on a weight basis, than the mussel, Mytilus edulis). We also found that not only anti-human aromatase, but also anti-human nuclear progesterone receptor (nPR) and anti-human gonadotropin-releasing hormone antibodies immunohistochemically stained snail neural cells. However, further experiments, involving gel electrophoretic separation, followed by immunostaining, of proteins extracted from the neural tissue, found at least two positively-stained bands for each antibody, none of which had masses matching the human proteins to which the antibodies had been raised. The anti-aromatase antibody even stained the 140 kDA ladder protein used as a molecular weight marker on the gels. Mass spectrometric analysis of the bands did not find any peptide sequences that corresponded to the human proteins. Our findings confirm that the presence of vertebrate-like sex steroids in molluscan tissues is not necessarily evidence of endogenous origin. The results also show that immunohistochemical studies using antibodies against human proteins are grossly non-specific and likely to have little or no value in studying steroid synthesis or activity in mollusks. Our conclusions are consistent with the fact that genes for aromatase and nPR have not been found in the genome of the snail or of any other mollusk. Our overarching conclusion, from this and our previous studies, is that the endocrinology of mollusks is not the same as that of humans or any other vertebrates and that continuing to carry out physiological and ecotoxicological studies on mollusks on the basis of this false assumption, is an unconscionable waste of resources.

Abstract P2-11-18: Weekly evaluation of α estrogen and progesterone receptors in women´s breast epithelium after oral combined hormonal contraceptive use for one month

Abstract Introduction: The increased risk of breast cancer is the most controversial and most feared adverse effect of combined oral contraceptives (COC) by women. The mechanisms by which COC would act on the breast parenchyma leading to its increased incidence, are not yet well known. Objectives: To calculate and compare α estrogen receptor (ERα) and progesterone receptor (PR) expression in the mammary epithelium in the first, second, third and fourth weeks of patients who do not use COC (natural cycle) and those who use one cycle of COC composed of 30 µg ethinyl estradiol (EE) and 150 µg levonorgestrel (LNG). Casuistic and Methods: A retrospective study with paraffin blocks of 118 women from February 2001 to February 2004. At the time, women were included in the pre-menopause who had a breast lump with the triple diagnosis of positive benignity and eumenorrheic during the last six months. The study project was analyzed and approved by the Research Ethics Committee of UNIFESP-EPM, under number CEP 1182/06. The patients underwent excision of the breast lumps and adjacent normal breast tissue fragments which were fixed in 10% buffered formalin. 31 patients were excluded and 87 patients were analyzed. The patients were divided into two groups: group A (with COC) consisted of 42 women who used an COC cycle composed of 30μg of EE and 150μg of LNG, group B (without COC) consisted of 45 women with natural cycles. The immunohistochemical reaction was performed in an automation device and the following antibodies were used: ERα antibody clone SP1 titer 1:500 and PR antibody clone PgR636 titer 1:400. The histological slides were read using conventional optical microscopy. After identifying the epithelial areas, 7 fields with 40X magnification were evaluated. Statistical analysis for parity was performed using Fisher's exact test. At age the Students t-Test was applied. ERα and PR counts were evaluated in the Generalized Estimation Equation (EEG) model. In order to compare the total ERα and PR counts by evaluation and group moments, we used the Analysis of Variance (ANOVA) and the Kolmogorov-Smirnov test. Statistical analyzes were performed using the programs SPSS 20.0 and STATA 12. For all statistical tests the significance level of 5% (p ≤ 0.05) was adopted. Results: The control group (without COC) had a higher mean age of 23.7 ± 5.9 years compared to the study group (with COC) with a mean age of 20.5 ± 5.1 years. Regarding parity, the study group (with COC) had 83.9% of nulliparous versus 73.3% in the control group (without COC). From the EEG model a statistically significant mean difference in ERα expression was observed in the fourth week in the study group (with COC) compared to the control group (without COC) with p <0.001. The comparison of PR expressions in the control group (without COC) in the fourth week or in the late luteal phase (LLP) with the ERα expressions, also in the fourth week (LLP) of the control group (without COC) the mean PR expression was higher and statistically significant than ERα expression with p <0.001. The group of women using COC showed higher average percentages of ERα (p <0.001) and PR (p <0.001) when compared to women in the control group (without COC). Conclusions: The average of expressions of the ERα and PR in users of an COC cycle composed of 30 µg EE and 150 µg LNG higher percentages of ERα (p <0.001) and PR (p <0.001) when compared to women from the control group (without COC). The ERα expression in the study group (with COC) in the fourth week (pause) was higher than the ERα expression in the fourth week (LLP) of the control group (without COC), a statistically significant difference (p <0.001). The expression PR in the fourth week of the control group (without COC) or LLP was higher than the ERα and this difference was statistically significant (p <0.001). Citation Format: Weekly evaluation of α estrogen and progesterone receptors in women´s breast epithelium after oral combined hormonal contraceptive use for one month [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-11-18.

Profile of Histopathological Type and Molecular Subtypes of Mammary Cancer of DMBA-induced Rat and its Relevancy to Human Breast Cancer

BACKGROUND: Animal models with mammary cancer that closely mimic human breast cancer for treatment development purposes are still required. Induction of 7,12-dimethylbenzanthracene (DMBA) to rats shows the histopathological features and mammary cancer characterization similar to humans. Examinations of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki67 expressions are crucial in deciding the treatment and prognosis of breast cancer. AIM: This research aimed to view histopathology images of mammary glands and expressions of ER, PR, Ki67, and HER2 of DMBA-induced rats. METHODS: After 1-week adaptation, 11 5-weeks-old female rats were induced with 20 mg/kg body weight (BW) of DMBA 2 times a week for 5 weeks. On week 29, nodules taken from the mammary gland were examined for hematoxylin-eosin staining and immunohistochemistry with p63, ER, PR, HER2, and Ki67 antibodies. The grading score used the Nottingham Grading System and molecular classifications based on St. Gallen 2013. RESULTS: Six rats had nodules, but the histopathologic features of one nodule showed normal mammary gland without cancer. The histopathological type of mammary cancer was cribriform carcinoma, comedo carcinoma, lipid-rich carcinoma, adenocarcinoma squamous, and adenomyepithelioma. Histopathological grading showed 60% of grade 3 and 40% of grade 2. P63 expression showed 60% positive and 40% negative. The frequency of ER, PR, HER2, and Ki67 of five nodules showed positivity: 40%, 60%, 60%, and 60%, respectively. Molecular subtypes of Luminal A, B, HER2, and triple-negative were 0%, 60%, 20%, and 20%, respectively. CONCLUSION: Histopathological features and molecular subtype of mammary cancer on rats induced with 20 mg/kg BW of DMBA showed similarity to human breast cancer.

High-mobility group AT-hook 2 expression in serous and endometrioid endometrial carcinomas

Background Subtyping of endometrial carcinoma, mainly high-grade cases, is a major pathological dilemma. Several biomarkers have been evaluated for differentiation between serous endometrial carcinoma (SEC) and endometrioid endometrial carcinoma (EEC), with variable sensitivity and specificity. Aim To evaluate the diagnostic role of high-mobility group AT-hook 2 (HMGA-2) in differentiation between SEC and EEC, compared with p16 and progesterone receptor (PR), and to evaluate HMGA-2 expression in endometrial carcinoma in relation to clinicopathological parameters. Materials and methods This study included 62 endometrial carcinoma specimens, classified as 20 biopsies of serous carcinoma and 42 endometrioid carcinomas. All specimens were subjected to immunohistochemistry using HMGA-2, p16, and PR antibodies. Results HMGA-2, p16, and PR showed significantly different expression between serous and endometrioid carcinomas. P16 showed more sensitivity and specificity (85 and 80.9%, respectively) than HMGA-2 (75 and 71.4%, respectively) in diagnosis of SEC. PR showed sensitivity and specificity of 88.1 and 90%, respectively, in diagnosis of EEC. Moreover, high HMGA-2 expression was significantly related to high tumor grade, advanced tumor stage, and presence of lymphovascular invasion. Conclusions HMGA-2 can be used as an adjunct biomarker in diagnosis of SEC, combined with p16 and PR. Moreover, HMGA-2 can be considered as a marker of aggressive tumor behavior in endometrial carcinoma.

Comprehensive immunohistochemical analysis based on the origin of leiomyosarcoma

Diagnostic criteria, biological behavior, and treatment approaches of leiomyosarcomas (LMS) may differ according to the origin of the tumor. This is important in terms of patient's management, especially in tumors located in the peritoneum and retroperitoneal sites. In our study, we aimed to demonstrate the immunophenotypic characteristics of uterine and extra-uterine LMS using alarge antibody panel, and to determine whether they potentially play arole in the differences among these tumor groups. Between 2006 and 2018, 29 uterine and 42 extra-uterine primary LMS were included in this study. Using tissue samples taken from the areas that best represented the tumor, an immunohistochemical study was performed on the blocks prepared by tissue micro-array method with estrogen and progesterone receptor (PR), WT-1, SMA, desmin, caldesmon, calponin, p16, p53, MDM2, CDK4, bcl-2, cyclin D1, fascin, EMMPRIN, FOXM1, c-erb-B2, c-Myc, PAX8, and CD117. Staining results of uterine and extra-uterine LMS were evaluated with these 20 antibodies. In uterine LMS compared with extra-uterine LMS, estrogen receptor (48% vs. 12%), PR (62% vs. 21%), desmin (79% vs. 50%), and EMMPRIN (69% vs. 45%) staining rate was detected higher. In extra-uterine LMS, caldesmon (88% vs. 69%), c-Myc (33% vs. 10%), and cyclin D1 (52% vs. 28%) were stained higher than uterine LMS (p < 0.05). No significant staining difference was detected with other antibodies. We concluded that estrogen receptor, PR, desmin, EMMPRIN, caldesmon, c-Myc, and cyclin D1 antibodies may help to determine primary origin of the tumor in LMS cases.

Expression of Progesterone Receptor and Its Association with Clinicopathological Characteristics in Meningiomas: A Cross-Sectional Study

BackgroundMeningiomas that are progesterone receptor positive have a low recurrence rate and good prognosis compared to those that are progesterone receptor negative. This study aimed to determine the prevalence of expression of progesterone in meningiomas and its association with clinicopathological characteristics.Materials and methodsThis was a cross-sectional laboratory-based study that was conducted at Muhimbili National Hospital. The study included 112 formalin-fixed paraffin-embedded tissue blocks of patients who were confirmed to have meningiomas on histological basis from January 2010 to December 2014. Immunohistochemical expression of progesterone receptor was tested using a primary monoclonal progesterone receptor antibody ready to use (IR 068 Dako). The χ2 test was used to determine the association between clinicopathological characteristics and progesterone receptor expression. A 2-tailed P < 0.05 was considered significant.ResultsThe mean age of the patients was 45.5 ± 3.601 years, and majority (66.1%, n = 74) were in the age group between 31 and 60 years. Also, majority of the patients (60%, n = 67) in this study were females. Over one-third of the cases (34.8%, n = 39) comprised of meningotheliomatous subtype, and majority of the cases (89.3%, n = 100) were of grade I. The prevalence of progesterone expression was 54.5% (n = 61), and only age was associated with progesterone receptor expression (P = 0.043).ConclusionThe finding of high expression of the progesterone receptor for grade I cases in this study indicates that progesterone receptor expression in meningiomas is of prognostic value and may be considered when evaluating patients for management. Lack of expression of progesterone receptor in all the malignant cases is intriguing and needs further studies that can investigate its prognostic role.

Abstract PS18-02: Highly multiplexed tissue-based cyclic immunofluorescence (t-CyCIF) for precision oncology identifies novel patterns of HER2 heterogeneity in breast cancer

Abstract Background Immunohistochemical (IHC) evaluation has shown that human epidermal growth factor receptor 2 (HER2) may not be expressed homogeneously among all cancer cells within a given tumor. The clinical significance of intratumoral HER2 heterogeneity is unclear. Exploration of tumor heterogeneity is facilitated by tissue imaging technologies such as t-CyCIF, a highly multiplexed immunofluorescence microscopy technique that permits visualization of up to 60 antigens and analysis on a single cell level from formalin-fixed, paraffin-embedded tissue. To utilize t-CyCIF for the evaluation of breast tumors, this study was undertaken to: 1) validate antibodies to be used against the clinically relevant markers HER2, estrogen receptor (ER) and progesterone receptor (PR), and 2) use these antibodies along with other validated antibodies to define the tumor microenvironment (TME) to interrogate breast tumors at a single cell level. Methods T-CyCIF is an iterative whole-slide imaging process, in which successive four-channel images, each involving different antibodies, are collected from the same sample and then merged to generate a high-dimensional representation used for visualization and analysis. In phase one of this study, 948 tissue cores (representing 295 patients in triplicate) were used to validate HER2, ER, and PR antibodies against a single antibody commonly used in clinical practice as a reference. Analyses were performed at the level of tissue cores, cells and pixels. Inter-assay analyses were performed comparing: t-CyCIF vs. IHC, the latter assessed by digital pathology and two pathologists; and also, t-CyCIF vs. fluorescence in situ hybridization (FISH) for HER2. In the second phase, following selection of validated HER2, ER and PR antibodies, expression of CD45, CD68, PD-L1, p53, Ki67, pRB and the androgen receptor (AR) were evaluated at a single cell level in 312 HER2+ invasive breast cancer samples, representing 104 patients, to better understand the TME, cancer cell heterogeneity and the cell identities/states present in breast carcinomas. Results In the first phase of the study, 13 different ER, PR or HER2 antibodies were analyzed. The pixel-to-pixel evaluation, which evaluates concordance in staining, resulted in r scores of 0.86 (ER; Pearson correlation), 0.93 (PR) and 0.94 (HER2) and correlation scores in single-cell comparisons ranged from 0.76 to 0.81. Correlation scores on the tissue core level were high in the inter-assay analyses, i.e. t-CyCIF vs. IHC (e.g. r scores up to 0.87 and 0.91 for ER and HER2, respectively, on t-CyCIF vs. Aperio; and 0.85 to 0.94 by pathology review) and t-CyCIF vs. HER2 FISH (r scores up to 0.71). This resulted in validated fluorophore-conjugated antibody panels for use in t-CyCIF that correspond well to established standards. In the second phase, single cell analysis of HER2+ breast cancer was performed. Cancer cells were defined as keratin positive and using t-Distributed Stochastic Neighbor Embedding (t-SNE) seven cancer cell clusters were identified including two HER2hi clusters differing in ER, p53, AR and PD-L1 expression, two HER2lo clusters differing in PR, Ki67, pRB, p53 and AR and three HER2neg clusters differing in PR, Ki67, ER, PD-L1 and AR. Heterogeneity scores were calculated based on diversity among clusters. Conclusion This study is the first to evaluate the performance of breast cancer-specific antibodies in a highly multiplexed imaging platform such as t-CyCIF. Using the validated antibody panel, we uncovered patterns of expression of markers relevant to breast cancer biology that correlate with HER2 high, low and negative states. Ongoing studies are looking at correlations between HER2 heterogeneity, responses to therapy and clinical outcomes. Citation Format: Jennifer L Guerriero, Jia-Ren Lin, Ricardo G Pastorello, Ziming Du, Shaolin Mei, Krishan Taneja, Stuart J Schnitt, Deborah A Dillon, Peter K Sorger, Sandro Santagata, Elizabeth A Mittendorf. Highly multiplexed tissue-based cyclic immunofluorescence (t-CyCIF) for precision oncology identifies novel patterns of HER2 heterogeneity in breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS18-02.

EKSPRESI PROGESTERONE RECEPTOR (PR) PADA BENIGN, ATYPICAL DAN ANAPLASTIC MENINGIOMA

ABSTRAK Background: Meningioma is the most common brain tumour in adult which treatment and follow-up depend on the histologic grade. Aim: This research aim is to assess the difference of Progesterone Receptor (PR) expression in 3 grade groups meningioma which are benign, atypical and anaplastic meningioma. Method: It is an analytic observational research with cross sectional design using immunohistochemical staining of PR antibody on 30 samples of paraffin blocks. Result: PR immunostaining positive in benign and atypical meningioma, and PR immunostaining negative in anaplastic meningioma with p value less than 0.05 (p = 0.000). Conclusion: There is difference of PR expression in each meningioma grade groups; benign, atypical and anaplastic meningioma. Key Words: progesterone receptor, meningioma

Ectopic omental deciduosis associated with pregnancy

Ectopic decidua (deciduosis) is most commonly localized in the ovary, uterus, cervix, and tuba uterina. It can rarely be observed within the peritoneum in pregnant women during laparotomy. More rarely, it can be localized in the omentum, appendix, liver, and spleen. It is usually incidental. In a 23-year-old female patient, a biopsy was taken from the thickening in a 4x3 cm area on the omentum during cesarean section. Microscopic evaluation revealed decidualized cells the majority of which had large polygonal eosinophilic cytoplasm and a few of which had vacuolated cytoplasm, that formed small nodules in the adipose tissue. Immunohistochemically, the decidualized cells were positive for vimentin, progesterone receptor antibody and negative for S-100, HMB-45, calretinin, pancytokeratin. The case was reported as ectopic omental deciduosis. Although ectopic omental deciduosis is a benign lesion, it may be confused with malignant tumors. Therefore, differential diagnosis should be made carefully.

The Expression of Progesterone Receptors in Meningiomas of Different Grades

Background: Meningiomas are slow growing intracranial and intraspinal neoplasms with a tendency to recur locally. WHO grades them as I (benign), II (atypical) and III (anaplastic) in order of their increasing aggressiveness, based on histological parameters and brain parenchymal invasion. Progesterone receptors (PR) are more prevalent amongst the lower grade meningiomas. The objective of this study was to determine the immunohistochemical expression of progesterone receptors in meningiomas of different grades.Material and Methods: A total of 100 cases were selected over a period of 2.5 years. Three to five microns’ thick sections stained with Hematoxylin and Eosin were examined microscopically by a team of two Histopathologists and graded into grades I, II and III, according to 2016 WHO classification criteria. Another section of the original tumor was stained with progesterone receptor antibody using the conventional immunoperoxidase method. Stained slides were than examined by the same team of Histopathologists and declared positive (if nuclear staining was observed in more than 10% of tumor cells) or negative. Statistical analysis was done using SPSS version 21.Results: Out of a total of 100 cases of meningioma, there were 79 cases of benign/typical WHO grade I, 15 cases of atypical/ WHO grade II and 6 cases of anaplastic/ WHO grade III tumor. PR status was positive in 89.8 % (71/79) of grade I meningiomas and 46.6 % (7/15) of grade II/Atypical meningiomas. The 06 cases of Anaplastic/WHO grade III tumors were negative for PR. There was a higher prevalence of Progesterone receptors in female patients (89.8%; 53/59) as compared to male meningioma patients (60.9%; 25/41).Conclusion: We observed a decreased expression of progesterone receptor in higher grades of meningioma in this study. It is an effort to explore conservative treatment options for inoperable lesions, as anti-progesterone therapy may hold a promise as a new treatment option in the near future.

Progesterone receptor isoform B expression in pulmonary neuroendocrine cells decreases cell proliferation

The progesterone receptor (PR) has been reported to play important roles in lung development and function, such as alveolarization, alveolar fluid clearance (AFC) and upper airway dilator muscle activity. In the lung, pulmonary neuroendocrine cells (PNECs) are important in the etiology and progression of lung neuroendocrine tumors (NETs). Women with lung NETs had significantly better survival rates than men, suggesting that sex steroids and their receptors, such as the PR, could be involved in the progression of lung NETs. The PR exists as two major isoforms, PRA and PRB. How the expression of different PR isoforms affects proliferation and the development of lung NETs is not well understood. To determine the role of the PR isoforms in PNECs, we constructed H727 lung NET cell models expressing PRB, PRA, Green Fluorescence Protein (GFP) (control). The expression of PRB significantly inhibited H727 cell proliferation better than that of PRA in the absence of progestin. The expression of the unrelated protein, GFP, had little to no effect on H727 cell proliferation. To better understand the role of the PR isoform in PNECs, we examined PR isoform expression in PNECs in lung tissues. A monoclonal antibody specific to the N-terminus of PRB (250H11 mAb) was developed to specifically recognize PRB, while a monoclonal antibody specific to a common N-terminus epitope present in both PRA and PRB (1294 mAb) was used to detect both PRA and PRB. Using these PR and PRB-specific antibodies, we demonstrated that PR (PRA&PRB) and PRB were expressed in the PNECs of the normal fetal and adult lung, with significantly higher PR expression in the fetal lung. Interestingly, PRB expression in the normal lung was associated with lower cell proliferation than PR expression, suggesting a distinct role of PRB in the PNECs. A better understanding of the molecular mechanism of PR and PR isoform signaling in lung NET cells may help in developing novel therapeutic strategies that will benefit lung NET patients in the future.

Abstract 2292: Comparison of Q Path and Aperio Image Analysis System for quantification of ER and PR by IHC in breast carcinoma TMAs

Abstract According to the Centers for Disease Control and Prevention, breast cancer is still one of the most common cancer in women, and top one or two in cancer mortality rates for all races of women. Novel drug treatments are needed to develop new treatments and clinical validation with IHC are common in research. Some common methods of validations are using Tissue MicroArrays (TMAs). In this study 5 TMAs containing approximately 100 cores each were stained with Estrogen Receptor (ER) and Progesterone Receptor (PR). Paraffin-embedded tissue blocks were obtained from the Indiana University Heath Pathology Laboratory under IRB approved protocols. Immunostainings with ER and PR antibodies (DAKO) were preformed using the DAKO-flex platform system at the IU Health Pathology Laboratory. The slides were digitally imaged using the Aperio Digital Imaging System. The SVS digital images were quantified using two different image analysis systems. One imaging system was the Aperio TMALab software, the other was Q Path image analysis software. Both systems were compared not only on the basis of performance, but among other parameters such as user friendliness and the ability to use a SVS image file type. When comparing the systems, the algorithm of Q Path was altered to closely match the algorithm of the standard Aperio positive pixel algorithm. Two measurements of antibody quantification were compared, one being positive pixel percentage, the other being an H Score. A regression line was used to show correlation between systems. Standard deviations were used to compare data against a standard pathology hand count of 0, 1, 2, and 3. The results show a strong correlation (R-squared value at or greater than 0.85) between the two imaging systems for both the positive pixel algorithm and H Score. The tightness may be due to consistent and rigorously explored in the past 20 years with both of these nuclear antibodies. Further studies should help distinguish any other possible errors using novel biomarkers and also delineate any discrepancies between a nuclear expressions against both a cytoplasmic and/or cell membranous expressions. In conclusion, Aperio Imaging analysis systems and Q path image analysis systems were in strong correlation, and therefore interchangeable in scientific research. Citation Format: Max Henry Jacobsen, Constance Temm, George Sandusky. Comparison of Q Path and Aperio Image Analysis System for quantification of ER and PR by IHC in breast carcinoma TMAs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2292.

Analytical and clinical performance of progesterone receptor antibodies in breast cancer.

Comparison of analytical and immunohistochemical performance of progesterone receptor (PR) antibodies with correlation to recurrence of invasive breast cancer treated with endocrine therapy. The binding-affinity kinetics of PR clones 1E2, 1A6, 16 and 636 were compared using synthetic peptides derived from identified epitopes on a Biacore T200. A cohort of 351 cases (Hormone Receptor (HR)+/HER2-) were stained for PR expression with immunohistochemistry (IHC) and scored according to ASCO/CAP criteria. The stability of the antigen/antibody complex was greater for the 1E2 clone compared to 1A6, 16 and 636 clones. PR IHC on archival tissue resulted in 94.3% (299/317) concordance with clones. Clones evaluated in this study had a high level of concordance with IHC despite PR (1E2) demonstrating higher analytical binding properties than other clones. In a minority of cases (1.3% for 1E2 and 2.5% for 636) IHC results could convert estrogen receptor (ER)-/PR- to ER-/PR+ tumors, making these patients potentially eligible for endocrine therapy.

Immunohistochemical evaluation of insulin-like growth factor receptor 1 in breast cancer

Introduction/Objective. Activation of insulin-like growth factor receptor (IGF-1R) results in cell transition from growth phase to synthesis phase of cell cycle. Breast cancer is categorized into prognostic and therapeutic subtypes based upon hormone receptor, estrogen receptor (ER), and progesterone receptor (PR) expression and human epidermal growth factor receptor 2 (HER-2) expression. The objective of this study was to examine the expression of IGF-1R in ? specific subtype invasive breast cancer and its correlation with basic histopathological and immunohistochemical prognostic parameters. Methods. Formalin-fixed paraffin-embedded tumor samples were obtained from 129 female patients with invasive breast cancer (I?III disease stage) with the follow-up ranging 36?108 months (average 48 months). For immunohistochemical staining, we used monoclonal antibodies for ER, PR, IGF-1R, and polyclonal antibody for HER-2. Results. IGF-1R inversely correlated with tumor stage (p = 0.017), tumor grade (p = 0.001), HER-2 (p = 0.003), whereas significant positive correlation was found with multifocality/multicentricity of breast cancer (p = 0.036), ER (p = 0.001) and PR (p = 0.0001) expression. Cox-regression analysis for relapse-free survival (RFS) showed that disease stage (p = 0.039) and HER-2 (p = 0.033) were independent prognostic factors. IGF-1R did not predict clinical outcome in patients with breast cancer (p = 0.488, Kaplan?Meier test for RFS). Conclusion. Patients with low stage and grade hormone-dependent breast cancer had a significantly higher IGF-1R expression than patients with triple negative or HER-2 overexpressed cancer. The present findings also highlight that IGF-1R expression in multicentric/multifocal breast cancer supports the key roles in tumor initiation.

Silencing of syndecan-binding protein enhances the inhibitory effect of tamoxifen and increases cellular sensitivity to estrogen.

Objective:Tamoxifen is used as a complementary treatment for estrogen receptor (ER)-positive breast cancer (BCa), but many patients developed resistance. The aim of this study was to examine the role of syndecan-binding protein (SDCBP) silencing in ER-positive BCa cells.Methods:In MCF-7/T47D cells, the effects of SDCBP silence/overexpression on cell proliferation and estrogenic response were examined. Cell proliferation was examined using the MTT assay and cell cycle regulators were examined by Western blot. Estrogen response was examined from a luciferase activity and evaluation of transcript levels of pS2 and progesterone receptor (PR) upon estrogen administration. Samples of ER-positive BCa were stained with ERα, PR, and SDCBP antibodies, and their expression correlations were analyzed.Results:We found that SDCBP silencing inhibited the proliferation of ER-positive BCa cells and arrested a greater number of cells in the G1 phase of the cell cycle compared to tamoxifen alone, while SDCBP overexpression limited the anti-cancer effects of tamoxifen. SDCBP silencing and overexpression also enhanced and attenuated the estrogenic response, respectively. Expression of SDCBP was negatively correlated with PR, ERα, and the PR/ERα ratio in ER-positive BCa tissue samples.Conclusions:SDCBP may be involved in tamoxifen resistance in ER-positive BCa. Tamoxifen treatment combined with SDCBP silencing may provide a novel treatment for endocrine therapy-resistant BCa.

Histopathological Analysis and Correlation of Ki67 and Progesterone Receptor Status with WHO Grading In Meningiomas

Background: Meningiomas are slow growing tumors that are among the most common of CNS neoplasms and form the most common CNS tumor to be reported above 35 years of age. Materials &amp; Methods: This retrospective study was carried out in the Department of Pathology during the period of January2011 to May2013. A total of 50 cases were graded according to the WHO 2016 grading criteria. The biopsy specimens were fixed in 10% neutral buffered formalin, sections was stained with Hematoxylin &amp; Eosin. Immunohistochemistry was done with Progesterone receptor and Ki67 antibodies for selected cases. Results: The incidence of meningiomas was 33.11% with a female sex predilection and most common in the 5th decade. Transitional meningioma was the most common variant to occur. The incidence of WHO Grade I, Grade II and Grade III meningiomas were 88%, 4% and 8% respectively. Comparison of Ki67 LI and PR score in various grades of meningiomas were done. The average Ki67 LI and PR score were 1.1%, 10.25; 6%, 3; 16%, 0 in grade I, II and III meningiomas respectively. p value showed a statistically significant difference between different grades of meningiomas with respect to PR and Ki67 status. Spearman correlation showed a clearly significant inverse relationship between the two antibodies. Conclusion: The use of immunohistochemical markers aids in determining the aggressive nature of the tumor, its recurrence potential and can be used as prognostic markers.

Androgen Receptor Expression in Endometrial Stromal Sarcoma: Correlation With Clinicopathologic Features.

Endometrial stromal sarcoma (ESS) is a rare neoplasm comprising only 0.2% to 1% of all uterine malignancies and occurs in women between 42 and 59 yr of age. ESSs frequently express estrogen receptor (ER) and progesterone receptor (PR). However, the published literature contains scant data on the expression and therapeutic/prognostic role of androgen receptor (AR) in ESSs. We undertook this study to characterize the expression of AR along with ER and PR in ESSs and correlate it with clinicopathologic features. The clinical details, slides, and blocks of 25 tumors from 24 patients (September 2010 to February 2016) were retrieved. The diagnosis and grade of ESS were reviewed and immunohistochemistry performed with anti-ER, PR, and AR antibodies. Ages ranged from 18 to 50 yr, with a mean age of 36 yr. Low-grade ESS (LGESS) and high-grade ESS (HGESS) were diagnosed in 15 and 9 patients, respectively. An 18-yr-old woman who initially had LGESS suffered a pelvic recurrence; that exhibited high-grade morphology. Our patients, especially those with HGESS, were much younger compared with published worldwide data. ER, PR, and AR immunoreactivity was observed in 14 (93.3%), 12 (80%), and 11 (73.3%) LGESSs, respectively. This is in contrast to HGESSs, in which 5 (50%) tumors had a triple-negative hormonal profile. AR, like ER and PR, was more frequently expressed in LGESS as compared with HGESS. Whether AR, in addition to ER and PR receptor status, may help guide adjuvant hormonal therapy needs further elucidation.

Breast cancer cells form primary tumors on ex vivo four-dimensional lung model

BackgroundBreast cancer mortality is most common in cancer in women, and there are no ex vivo models that can capture the primary growth of tumor with fidelity to the in vivo tumor growth. In this study, we grew human breast cancer cell lines in an acellular lung matrix of the ex vivo four-dimensional lung model to determine if they form primary tumor and the extent to which they mimic the histology and characteristics of the human tumors. Materials and methodsRat lungs were harvested, decellularized, and placed in a bioreactor. To study the primary tumor growth, we seeded the lung via the trachea with human breast cancer cells SUM159, MCF7, or MDMB231 and perfused the pulmonary artery with oxygenated media. Lobectomies were performed and processed for hematoxylin and eosin, Ki-67, caspase-3, estrogen receptor, and progesterone receptor antibodies. ResultsAll three cell lines grew in the ex vivo four-dimensional model and formed perfusable tumor nodules with similar histology and morphology as the primary tumors. SUM159 and MDAMB231 showed higher proliferation and apoptotic indices than MCF7. In addition, MCF7 retained its estrogen receptor and progesterone receptor positivity, whereas SUM159 and MDAMB 231 did not have any staining. ConclusionsOverall, our study showed that human breast cancer cells can be grown on the ex vivo four-dimensional lung model, which then form primary tumor nodules that mimic the morphology and histology of the original tumor.