Absence Of Progesterone Receptors Research Articles

Different Effect of Dienogest on Endometrium Mesenchymal Stem Cells Derived from Healthy and Endometriosis Tissues.

Endometriosis (EM) is an inflammatory condition in which the endometrium is observed to develop outside the uterine cavity. Endometrium has conventionally been recognized as a rich source of endometrial mesenchymal stem cells (E-MSCs). Due to their secretion of proteins and other factors that modulate tissue function, E-MSCs are essential for tissue balance and repair in regenerative medicine. The influence of dienogest, a medication frequently prescribed for EM, on E-MSCs has not been extensively investigated. To explore effects of dienogest on the E-MSCs derived from healthy (E-MSCs-control) and diseased (E-MSCs-endometriosis) endometrial tissue samples in vitro. The main outcome is that dienogest-based treatments might also be designed to target stem cells in endometrial tissues, which enables it to effectively regulate disease progression. In vitro study. We collected samples from healthy and diseased endometrial tissues. E-MSCs were derived from both healthy and EM tissues. The effect of dienogest (VISANNE) on E-MSCs was assessed by examining cell proliferation, telomerase activity, cell migration, and estrogen secretion levels after the isolation and characterization of E-MSCs. We discovered that cellular proliferation rate was higher in the E-MSCs derived from EM tissues compared to those derived from healthy tissue. The proliferation rate and telomerase activity were both suppressed by dienogest treatment, particularly in E-MSCs-endometriosis. The drug treatment also resulted in a decrease in the migration capacity of E-MSCs-endometriosis, from 60.4% to 59.2%. The expression of CXCL12, Ki67, and beta-catenin was analyzed in both E-MSCs-endometriosis and E-MSCs-control. The CXCL12 and Ki67 expressions were quite elevated in the E-MSCs-endometriosis without drug treatment compared to the E-MSCs-control. Following the treatment, these levels declined drastically to the levels close to E-MSCs-control. Similarly, this decrease in gene expression was accompanied by a decrease in estrogen secretion into the medium. This research demonstrates that dienogest exerts a substantial impact on both stromal and stem cells, as it effectively controls the disease by reversing EM markers, despite the absence of progesterone receptors on endometrial stem cells.

Abstract PO4-15-09: Unraveling the influence of progesterone receptor status on endocrine therapy sensitivity: insight from epigenetic and fragmentomics ctDNA profiling in estrogen receptor positive, HER2 negative metastatic breast cancer (MBC)

Abstract Background: In patients (pts) with estrogen receptor (ER) positive (pos), HER2 negative (neg) MBC, the absence of progesterone receptor (PR) expression is generally associated with a poorer endocrine therapy (ET) response and an unfavorable prognosis. However, real-time molecular changes during ET according to PR status are still not fully understood. The aim of this study was to examine the prognostic impact of PR and its association with the methylation levels of ESR1 promoters A (promA) and B (promB) at different timepoints in pts with ERpos HER2neg MBC who received first-line ET. Methods: Pts were enrolled in the prospective multicenter MAGNETIC.1 trial (CRO-2018-56) between January 2018 and January 2023. As first-line ET, pts received either fulvestrant or AIs with or without CDK4/6 inhibitors (CDK4/6i) as first-line ET. ctDNA samples were collected at baseline (T0) and at 3-month intervals (T3 and T6) and analyzed through methylation-specific (MS) droplet digital PCR (ddPCR), ddPCR fragmentomics and next generation sequencing (NGS). Clinico-pathological differences across the PR expression spectrum were analyzed using Fisher’s exact test. Matched pairs variations across timepoints (T0, T3, T6) of ACTBfragments distribution and ESR1 promA and promB were tested through Wilcoxon signed rank test. Results: Out of the 111 enrolled pts, 28 had PRneg MBC, of which 20 had an invasive ductal carcinoma (IDC) histotype, and 10 were diagnosed as de novo disease. Bone was the most common metastatic site both in the PRpos and PRneg subgroups (75% vs 73%), most pts received ET+CDK4/6i (96% vs 95%). ESR1 and PIK3CA mutations were respectively detected in 8% and 6%, and in 23% and 25% pts respectively for PRpos and PRneg. The prognostic impact of PR status was evident for both PFS (median 38 mos and 14 mos respectively for PRpos and PRneg, P = 0.0048) and OS (median not reached and median 33 mos respectively for PRpos and PRneg, P= 0.001). A significant increase in promB was observed at T3 vs T0 and at T6 vs T3 in the PRpos subgroup (respectively P=0.0158 and P< 0.001) but not in the PRneg. When comparing T6 to T0, no significant differences were observed regardless of PR status. At T3, significant decreases were observed in both the PRpos and PRneg populations for ACTBshort (P < 0.001 and P=0.03, respectively), ACTBmedium (P=0.0049 and P= 0.035, respectively) and ACTBlong(P< 0.001 and P< 0.001, respectively), compared to T0. In the comparison of T6 to T3, a significant variation in ACTBshort levels was observed in both subgroups (P< 0.001 for PRpos and P=0.012 for PRneg). while a significant reduction in ACTBmedium levels was observed only in the PRpos population when comparing T6 to T0 (P< 0.001). Conclusions: PRneg status was confirmed as an unfavorable prognostic factor with respect to PRpos both for PFS and OS, potentially due to different ET sensitivity. Epigenetic ctDNA profiling revealed different dynamics of ESR1 promB between PR-positive and PR-negative MBC, suggesting a distinct role of ESR1 in the onset of ET resistance within the two subgroups. Citation Format: Lorenzo Foffano, Elisabetta Molteni, Arianna Dri, Alessandra Franzoni, Linda Cucciniello, Lucia Da Ros, Silvia Buriolla, Silvia Bolzonello, Claudia Noto, Stefania Russo, Simon Spazzapan, Elena Nascimbeni, Brenno Pastò, Giada Targato, Serena Della Rossa, Marta Bonotto, Alessandro Marco Minisini, Giuseppe Damante, Barbara Belletti, Lorenzo Gerratana, Fabio Puglisi. Unraveling the influence of progesterone receptor status on endocrine therapy sensitivity: insight from epigenetic and fragmentomics ctDNA profiling in estrogen receptor positive, HER2 negative metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-15-09.

Abstract PO1-16-08: Real-World Outcomes of Patients Receiving First-line Palbociclib Plus Endocrine Therapy in Spain: Subgroup Analysis Based on Tumor Grade, Progesterone Receptor, Ki-67 and Histological Subtype from PALBOSPAIN Study

Abstract Background PALBOSPAIN (NCT04874025) is an observational, multicenter study evaluating real-world patterns and outcomes of first-line treatment with palbociclib plus endocrine therapy (ET) in routine clinical practice in Spain. Results from real-world progression-free survival (rwPFS) and overall survival (OS) in the total population, as well as subgroup analysis according to endocrine sensitivity, age, menopausal status, location and number of metastatic sites have been previously reported. Here, we present the prognostic impact of pathological features in metastatic breast cancer patients treated with Palbociclib plus endocrine therapy. Methods Patients diagnosed with hormone-receptor positive and HER2 negative ABC who started first-line treatment with palbociclib plus ET between November 2017 and November 2019 were included. We retrospectively collected clinical-pathological and treatment response data from patient medical records. Estrogen receptor (ER), Progesterone receptor (PR), and Ki67 were assessed by immunohistochemistry (IHC). HER2 was assessed by IHC or fluorescence in situ hybridization (FISH). To evaluate the prognostic role of proliferation index, Ki-67 cut-off was set at 20%. If results of several biopsies were available, the most recent one was used for analysis. Survival analysis (rw-PFS, OS) were estimated using the Kaplan–Meier method with log-rank test. Times for event-free patients at the time of data cutoff in all survival analyses were calculated from the date of treatment start to the date of last follow-up. The association between prognostic factors and survival was examined using Cox proportional hazards regression model. Results A total of 762 patients from 35 hospitals met inclusion and exclusion criteria and were included in the analysis. The cut-off date for this analysis was July 2022 and the median duration of follow-up was 29 months. The distribution of the pathological features is shown in Table 1. Patients with histological grade 1 tumors had a median rwPFS of 33 months, while grade 2 tumors experienced a median rwPFS of 24 months and grade 3 tumors had the poorest outcome with a median rwPFS of 19 months. Median OS was 43, 42 and 40 months for grade 1, 2 and 3 respectively. Patients with Ki-67 < 20% had better rwPFS (35 vs 20 months; HR 0.60, p=0.004) and OS (not reached [NR] vs 35 months; HR 0.66, p=0.002) than those with Ki-67 ≥20% Patients with low ki-67 had better outcomes compared with those with high Ki-67. rwPFS (35 vs 20 months; HR 0.60, p=0.004) and OS (not reached [NR] vs 35 months; HR 0.66, p=0.002) for Ki 67 < 20% and ≥20% respectively. No differences were found according to histological subtype, with similar median rwPFS (23 vs 25 months; HR 0.96, p= 0.77) and OS (42 vs 43 months; HR 0.94, p=0.74) for ductal and lobular carcinomas respectively. Double hormone receptor positive tumors (ER+/PR+) had significant longer rwPFS (27 vs 18 months; HR 0.72, p=0.001) and OS (44 vs 40 months; HR 0.73, p= 0.01) compared with ER+/PR- tumors. Conclusions Grade 3 tumors, Ki 67 ≥20% and absence of PR are associated with reduced rw-PFS and OS in patients treated with palbociclib plus ET in clinical practice. Pathologic results have a prognostic role and may be useful to identify patients who derive more benefit with first-line CDK 4/6 inhibitors plus ET treatment. Table 1 Pathological Characteristics in PALBOSPAIN study Citation Format: Fernando Moreno, Meritxell Bellet- Ezquerra, Luis Manso, Fernando Henao, Antonio Antón, Serafin Morales Murillo, Pablo Tolosa, Verónica Obadía, Teresa Sampedro, Raquel Andrés, Lourdes Calvo, Elena Galve, Rafael López, Francisco Ayala de la Peña, Sara López-Tarruella, Blanca Hernando, Laia Boronat, J. Ignacio Chacón, Noelia Martínez-Jáñez. Real-World Outcomes of Patients Receiving First-line Palbociclib Plus Endocrine Therapy in Spain: Subgroup Analysis Based on Tumor Grade, Progesterone Receptor, Ki-67 and Histological Subtype from PALBOSPAIN Study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-16-08.

Anticancer Effects of Fucoxanthin through Cell Cycle Arrest, Apoptosis Induction, and Angiogenesis Inhibition in Triple-Negative Breast Cancer Cells.

The absence of progesterone receptors, estrogen receptors, and human epidermal growth factor receptor-2 restricts the therapy choices for treating triple-negative breast cancer (TNBC). Moreover, conventional medication is not highly effective in treating TNBC, and developing effective therapeutic agents from natural bioactive compounds is a viable option. In this study, the anticancer effects of the natural compound fucoxanthin were investigated in two genetically different models of TNBC cells: MDA-MB-231 and MDA-MB-468 cells. Fucoxanthin had a significant anticancer effect in both cell lines at a concentration range of 1.56-300 µM. The compound decreased cell viability in both cell lines with higher potency in MDA-MB-468 cells. Meanwhile, proliferation assays showed similar antiproliferative effects in both cell lines after 48 h and 72 h treatment periods. Flow cytometry and Annexin V-FITC apoptosis assay revealed the ability of fucoxanthin to induce apoptosis in MDA-MB-231 only. Cell cycle arrest analysis showed that the compound also induced cell cycle arrest at the G1 phase in both cell lines, accompanied by more cell cycle arrest in MDA-MB-231 cells at S-phase and a higher cell cycle arrest in the MDA-MB-468 cells at G2-phase. Wound healing and migration assay showed that in both cell lines, fucoxanthin prevented migration, but was more effective in MDA-MB-231 cells in a shorter time. In both angiogenic cytokine array and RT-PCR studies, fucoxanthin (6.25 µM) downregulated VEGF-A and -C expression in TNF-α-stimulated (50 ng/mL) MDA-MB-231, but not in MDA-MB-468 cells on the transcription and protein levels. In conclusion, this study shows that fucoxanthin was more effective in MDA-MB-231 TNBC cells, where it can target VEGF-A and VEGF-C, inhibit cell proliferation and cell migration, and induce cell cycle arrest and apoptosis-the most crucial cellular processes involved in breast cancer development and progression.

The clinical value of progesterone receptor expression in luminal breast cancer: A study of a large cohort with long-term follow-up.

The routine assessment of progesterone receptor (PR) expression in breast cancer (BC) remains controversial. This study aimed to evaluate the role of PR expression in luminal BC, with emphasis on the definition of positivity and its prognostic significance as compared to Ki67 expression. A large cohort (n=1924) of estrogen receptor (ER)-positive/HER2-negative BC was included. PR was immunohistochemically (IHC) stained on full face sections and core needle biopsies (CNB) where the optimal scoring cutoff was evaluated. In addition, the association of PR with other clinicopathological factors, cellular proliferation, disease outcome, and response to adjuvant therapy were analyzed. Although several cutoffs showed prognostic significance, the optimal cutoff to categorize PR expression into two clinically distinct prognostic groups on CNB was 10%. PR negativity showed a significant association with features of aggressive tumor behavior and poor outcome. Multivariate analyses indicated that the association between PR negativity and poor outcome was independent of tumor grade, size, node stage, and Ki67. PR negativity showed independent association with shorter survival in patients who received endocrine therapy whereas Ki67did not. PR IHC expression provides independent prognostic value superior to Ki67. Routine assessment of PR expression in BC using 10% cutoff in the clinical setting is recommended. In this study, we have established an optimal approach to determine the prognostic value of progesterone receptor expression in estrogen receptor-positive breast cancer patients. To do this, the levels of progesterone receptor were measured in a large cohort of estrogen receptor-positive breast cancer patients. We have refined the definition of progesterone receptor positivity in estrogen receptor-positive breast cancer. We show that progesterone receptor expression adds prognostic and predictive value of endocrine therapy in estrogen receptor-positive breast cancer patients, and our results show that the absence of progesterone receptor is associated with poorer outcomes independent of tumor grade, size, node stage, and Ki67 expression.

Anticancer Effects of Thymoquinone through the Antioxidant Activity, Upregulation of Nrf2, and Downregulation of PD-L1 in Triple-Negative Breast Cancer Cells.

The variety of therapies available for treating and preventing triple-negative breast cancer (TNBC) is constrained by the absence of progesterone receptors, estrogen receptors, and human epidermal growth factor receptor 2. Nrf2 (nuclear factor-erythroid 2-related factor), and PD-L1 (program cell death ligand 1), a downstream signaling target, have a strong correlation to oxidative stress and inflammation, major factors in the development and progression of TNBC. In this study, the genetically distinct MDA-MB-231 and MDA-MB-468 TNBC cells were treated with the natural component thymoquinone (TQ). The results show that TQ exhibits considerable antioxidant activity and decreases the generation of H2O2, at the same time increasing catalase (CAT) activity, superoxide dismutase (SOD) enzyme, and glutathione (GSH). Additionally, the results show that TQ treatment increased the levels of the different genes involved in the oxidative stress-antioxidant defense system PRNP, NQO1, and GCLM in both cell lines with significant large-fold change in MDA-MB-468 cells (+157.65 vs. +1.7, +48.87 vs. +2.63 and +4.78 vs. +2.17), respectively. Nrf2 mRNA and protein expression were also significantly increased in TQ-treated TNBC cells despite being higher in MDA-MB-468 cells (6.67 vs. 4.06). Meanwhile, TQ administration increased mRNA levels while decreasing PD-L1 protein expression in both cell lines. In conclusion, TQ modifies the expression of multiple oxidative-stress-antioxidant system genes, ROS, antioxidant enzymes, Nrf2, and PD-L1 protein, pointing to the therapeutic potential and chemopreventive utilization of TQ in TNBC.

Palbociclib and letrozole in hormone-receptor positive advanced breast cancer: Predictive response and prognostic factors

CDK 4/6 inhibitors have been yielding propitious results when with hormone therapy in the management of Her2-negative and hormone-receptor (HR)-positive metastatic breast cancer, palbociclib being one of the first molecules investigated in this setting. However, the response to CDK4/6 inhibitors is variable. To identify predictive and prognostic factors of response to this therapeutic regimen. Eligible patients were females with HR+ and Her2- advanced breast cancer, receiving Palbociclib in combination with Letrozole. PFS was the primary endpoint in the evaluation of response to treatment. This survival was then further segregated according to various characteristics: histological (type, grade, hormone receptors), metastatic site, line of treatment, response type at initial assessment, and best response achieved. The data was then processed by two statistical analysis models: Kaplan-Meier and univariate preceding multivariate Cox proportional risks. Sixty patients were included and followed for a median follow-up duration of 15.98 months. PFS recorded a median of 19.07 months (95% CI=15.43-22.71). PFS had a median of 12.99 months in the absence of progesterone receptors (vs 20.05 months in the case of positive estrogen and progesterone receptors; P = 0.046), a median of 13.02 months in the presence of liver metastases (vs 22.98 months in the absence of liver metastases; P = 0.007), and 15.94 months in the case of second-line and beyond (vs 22.98 months in the case of first-line; P = 0.033). Regarding the Hazard Ratio of progression, we note age (HR 0.941; P = 0.019), liver metastases (HR 2.751; P = 0.051), response at initial evaluation (HR<1; P < 0.001) and best response (HR<1; P = 0.003). PFS reached similar figures to those of international studies. The absence of progesterone receptors, presence of liver metastases, and use as second-line or beyond are associated with a reduced median PFS. One year age increase (protective factor), liver metastases (risk factor), response at initial evaluation, and best response achieved are identified as the most predictive factors of the response to this treatment regimen and of the progression risk.

Achieving High Breast Cancer Survival for Women in Rural and Remote Areas.

Background:Significant improvements in breast cancer survival have been made in the past few decades in many developed countries including Australia with a five-year relative survival of 90%. The aim of the present study is to obtain a brief estimate of the relative importance of demographic factors such as rurality, socio-economic standard and ethnicity versus traditional risk factors for women diagnosed with breast cancer in Far North Queensland, Australia. Methods:This was a retrospective longitudinal study of all women diagnosed with their first episode of breast cancer in 1999-2013 in Far North Queensland, Australia. Cox proportional hazards regression analysis was used to identify factors independently associated with mortality for women with any type of breast cancer (in situ or invasive) and for women with invasive cancer. Life tables were used to assess five and ten-year absolute survival. Standard linear regression and binary logistic regression were used to identify any association between demographic factors and late presentation. Results:Five and ten-year absolute survival was 0.90 and 0.86 respectively. Aboriginal and Torres Strait Islander status, remoteness of area of residence, and socioeconomic status were not associated with more advanced disease at presentation or increased risk of breast cancer death. Only traditional risk factors such as increased tumour size, absence of progesterone receptor, high tumour grade and presence of metastasis in axillary lymph nodes were associated with increased risk of breast cancer death. Conclusion:The effect of the classical risk factors on breast cancer mortality outweighs the effects of demographic factors. The fact that ethnicity, remoteness and socioeconomic status is not associated with late presentation or breast cancer death suggests that given appropriate resources it may be possible to close the gap of inequalities in breast cancer.

Anticancer potential of (-)-epicatechin in a triple-negative mammary gland model.

The main aim of this work was to analyse the potential tumour growth inhibition effects of (-)-epicatechin (EC). Triple-negative breast cancer (TNBC) is an invasive form of cancer characterized by the absence of progesterone receptor, estrogen receptor and human epidermal growth factor receptor 2. Doxorubicin (DOX) is widely used for its anti-tumour activity. EC belongs to the flavanol subfamily and is a candidate molecule for the adjuvant treatment of cancer due to its antiproliferative activities. Evaluation of EC effects and pathways involved in a model of TNBC. EC inhibited tumour growth as efficiently as DOX (inhibition rates of 74% and 79% for EC and DOX, respectively). The evaluation of adenosine monophosphate-activated protein kinase (AMPK) and Akt phosphorylation and mTOR expression indicates that EC modulates these pathways, resulting in the inhibition of cell proliferation. Additionally, we found an increase in the survival of EC-treated animals compared with control-treated animals. This effect was similar to the effects induced by DOX (survival rates of 44% and 30% for EC and DOX, respectively). EC has antiproliferative properties and increases survival in a model of TNBC. These effects may occur through the modulation of deregulated AMPK and Akt/mTOR signalling pathways.

Abstract PS10-33: Analysis of factors associated with pathological complete response (pCR) in patients with HER2+ breast cancer receiving neoadjuvant chemotherapy

Abstract Background: Pathologic complete response (pCR) following neoadjuvant chemotherapy (NAC) is associated with improved survival outcomes among women with HER2 positive (HER2+) breast cancer. We aimed to analyze the clinical, pathological and molecular factors associated with pCR in our series of HER2+ breast cancer patients. Methods: Between 2009 and 2019, breast cancer patients receiving NAC at our centre were enrolled in a prospective database. For this study we selected women with HER2+ unilateral breast cancer stages II or III who received anthracycline-taxane NAC regimens (with trastuzumab given concurrently with the taxane) and subsequently underwent breast and axillary surgery with curative intent. Medical charts of these 161 women were retrospectively reviewed to determine what clinical, pathological and molecular characteristics were associated with pCR using bivariate and multivariate analysis. Results: Of the 161 HER2+ women median age at diagnosis was 49 years (range 25-78) with 90 (56%) women under age 50. Total of 104 (65%) tumors were stage II, 108 (67%) expressed estrogen and/or progesterone receptors, 139 (86%) had HER2 3+ expression by immunohistochemistry (IHC) and 22 (14%) had HER2 IHC 2+ expression with amplified HER2 on fluorescence in situ hybridization (FISH) test. The NAC regimens were: Doxorubicin-Cyclophosphamide-Paclitaxel for 83 (52%) and Fluorouracil-Epirubicin-Cyclophosphamide-Docetaxel for 78 (48%) women. A total of 73 patients [45%; 44/108 HR+ (41%) and 29/53 HR- (55%)] achieved pCR (p=0.94). pCR rate among HER2 IHC 3+ tumors was 69/139 (50%), while for HER2 IHC 2+ tumors was 4/22 (18%). On bivariate analysis HER2 IHC 3+, absence of estrogen receptors and absence of progesterone receptors were predictive of pCR, while age, menopausal status, histologic subtype, tumor grade and NAC regimen were not. In the multivariate model only HER2 IHC 3+ expression remained a significant predictor of pCR (OR =4.443, 95% CI 1.376 - 14.344). Conclusion: Our analysis suggests that for HER2+ breast cancers treated with NAC with anthracycline-taxane and trastuzumab, HER2 IHC 3+ expression is associated with a higher rate of pCR compared to HER2 IHC 2+ expression with FISH amplification. Further analysis in a larger cohort is warranted. Citation Format: Neda Stjepanovic, Katarzyna Jerzak, Maureen Trudeau, Andrea Eisen, Sonal Gandhi, Ellen Warner, Danilo Giffoni MM Mata, Anthony Lott, Maria Romero, Sharon Lemon-Wong, Althea VanMassop, Xingshan Cao, William Tran, Rossanna Pezo. Analysis of factors associated with pathological complete response (pCR) in patients with HER2+ breast cancer receiving neoadjuvant chemotherapy [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 PS10-33.

Abstract IA020: Chromatin regulation of the endometrium: What are our models telling us?

Abstract ARID1A and PI3-Kinase (PI3K) pathway alterations are common in neoplasms originating from the uterine endometrium. ARID1A is a SWI/SNF chromatin-remodeling complex subunit. ARID1A loss in the mouse endometrial epithelium leads vaginal bleeding when combined with PI3K pathway activation. Sorted mutant endometrial epithelial cells display gene expression and promoter chromatin signatures associated with epithelial-to-mesenchymal transition (EMT), inflammation and estrogen signaling in vivo. ARID1A loss leads to the expression of EMT genes, suggesting ARID1A normally maintains endometrial epithelial cell identity by repressing mesenchymal cell fates. In contrast to its repressive roles, ARID1A is required for the activation estrogen responsive genes, including the progesterone receptor (PGR). Estrogen responsive genes are marked by bivalent chromatin domains containing both histone H3 lysine 4 trimethylation (H3K4me3) and lysine 27 trimethylation (H3K27me3). High H3K27me3 correlates with low PGR expression, suggesting Polycomb Repressive Complex 2 (PRC2)-mediated H3K27me3 normally silences PGR. In support of this, pharmacological inhibition of PRC2 partially rescues PGR activation is estrogen treated, ARID1A-deficient cells. Given the known antagonistic relationship between SWI/SNF and PRC2 complexes, we propose that SWI/SNF normally opposes PRC2 mediated silencing of the PGR promoter in response to estrogen, leading to PGR expression. In the ARID1A mutant endometrium, PGR promoter silencing by PRC2 is maintained. In the absence of PGR, progesterone cannot oppose the actions estrogen in the endometrium, leading to unopposed estrogen signaling. Our data demonstrate ARID1A has both activating and repressive roles in the endometrium, and ARID1A loss contributes to multiple aspects of disease pathogenesis. Citation Format: Mike R. Wilson, Jake J. Reske, Ronald L. Chandler. Chromatin regulation of the endometrium: What are our models telling us? [abstract]. In: Proceedings of the AACR Virtual Special Conference: Endometrial Cancer: New Biology Driving Research and Treatment; 2020 Nov 9-10. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(3_Suppl):Abstract nr IA020.

The role of amplified in breast cancer 1 in breast cancer: A meta-analysis.

Amplified in breast cancer 1 (AIB1) expression is known to be involved in the initiation and progression of malignant breast cancer (BC), but its prognostic role remains uncertain. This meta-analysis assessed reported studies to evaluate this relationship. Electronic databases were systematically reviewed to collect eligible studies using pre-established criteria. Hazard ratios (HRs) or odds ratios (ORs) and 95% confidence intervals (CIs) were pooled to estimate the impact of AIB1 protein expression on overall survival (OS) and clinicopathologic properties of BC cases. Nine eligible studies, including 6774 patients, were finally assessed by the current clinical meta-analysis. AIB1 positivity correlated with reduced OS (pooled HR = 1.409, 95% CI 1.159-1.714, P = .001). AIB1 overexpression also impacted prognosis as shown by univariate (pooled HR = 1.420, 95% CI 1.154-1.747, P = .001) and multivariate (pooled HR = 1.446, 95% CI 1.099-1.956; P = .009) analyses. Notably, subgroup analyses also revealed that AIB1 overexpression was associated with poor OS in some subgroups, such as ER-positive group (pooled HR = 1.511, 95% CI 1.138-2.006, P = .004), ER-positive without tamoxifen administration group (pooled HR = 2.338, 95% CI 1.489-3.627, P < .001), and premenopausal women group (pooled HR = 1.715, 95% CI 1.231-2.390, P = .001). Additionally, high AIB1 protein levels were associated with HER2 positivity (pooled OR = 0.331, 95% CI 0.245-0.448; P < .001), poorly differentiated histological grade (pooled OR = 0.377, 95% CI 0.317-0.448; P < .001), high Ki67 (pooled OR = 0.501, 95% CI 0.410-0.612; P < .001), presence of lymph node metastases (pooled OR = 0.866, 95% CI 0.752-0.997; P = .045), and absence of progesterone receptor (pooled OR = 1.447, 95% CI 1.190-1.759; P < .001). This analysis demonstrated that AIB1 overexpression is related to aggressive phenotypes and unfavorable clinical outcomes in BC, and might involve in tamoxifen resistance. AIB1 may be a new prognostic biomarker and therapeutic target in BC.

Male breast cancer: Specific biological characteristics and survival in a Portuguese cohort.

Male breast cancer (BC) represents an individual subtype of BC, with therapeutic procedures based on female BC therapy results. The present study evaluated the parameters currently used for the characterization and therapy of male BC, and their association with disease-free (DFS) and overall survival (OS), aiming to obtain a comprehensive basis to improve the personalized care of male BC. A total of 196 patients from March 1970 to March 2018 (mean follow-up, 84.9 months) were profiled, using clinicopathological review, molecular assessment [BRCA1/2, DNA repair associated (BRCA1/2) status, immunohistochemistry, fluorescence in situ hybridization and DNA flow cytometry] and Cox regression statistical analysis. The median age of patients was 66.5 years. At presentation, 39.2% of patients with invasive carcinomas were in anatomic stage (AS) I. Patients exhibited primarily invasive carcinomas of no special type, histological grade 2, estrogen receptor α-(ERα) and progesterone receptor (PR)-positive, receptor tyrosine kinase erbB-2-negative, high Ki-67, Luminal B-like and aneuploid tumors. A total of 13 of the 44 (29.5%) BRCA-evaluated patients exhibited BRCA2 mutations, significantly associated with family history (FH), bilaterality, high Ki-67 expression, absence of PR and Luminal B-like tumors. Bilaterality was associated with the occurrence of non-breast primary neoplasms (NBPN). The 5 and 10-year DFS rates, excluding patients with distant metastasis, NBPN and in situ carcinomas (n=145) were 65.9 and 58.2%, respectively, and the 5 and 10-year OS rates were 77.5 and 59.2%, respectively. In the univariate analysis, Luminal B-like subtype, BRCA2 mutations, high Ki-67 expression, and AS II and III were significantly associated with shorter DFS and OS. In addition, age >70 years was associated with low OS. In the multivariate analysis, FH, AS II and III, and Luminal B-like subtypes were associated with poorer OS. In conclusion, the data from the present study emphasize the high incidence of BRCA2 mutation in male BC, and its association with FH, bilaterality, high Ki-67 expression, negative PR expression and Luminal B-like subtypes, and with shorter DFS and OS in univariate analysis.

Prognostic Value of the Progesterone Receptor by Subtype in Patients with Estrogen Receptor-Positive, HER-2 Negative Breast Cancer.

In estrogen receptor-positive (ER+), human epidermal growth factor receptor 2 (HER-2) negative breast cancers, the progesterone receptor (PR) is an independent prognostic marker. Little is known about the prognostic value of PR by tumor grade. We assessed this in two independent datasets. Women with primary operable, invasive ER+ HER-2 negative breast cancer diagnosed between 2000 and 2012, treated at University Hospitals Leuven, were included. We assessed the association of PR status and subtype (grade 1-2 vs. grade 3) with distant recurrence-free interval (DRFI) and breast cancer-specific survival. The interaction between PR status and subtype was investigated, and associations of PR status by subtype were calculated. The BIG 1-98 data set was used for validation. In total, 4,228 patients from Leuven and 5,419 from BIG 1-98 were analyzed. In the Leuven cohort, the adjusted hazard ratio (HR) of PR-positive versus PR-negative tumors for DRFI was 0.66 (95% confidence interval [CI], 0.50-0.89). For the interaction with subtype (p = .34), the HR of PR status was 0.79 (95% CI, 0.61-1.01) in luminal A-like and 0.59 (95% CI, 0.46-0.76) in luminal B-like tumors. In luminal A-like tumors, observed 5-year cumulative incidences of distant recurrence were 4.1% for PR-negative and 2.8% for PR-positive tumors, and in luminal B-like 18.7% and 9.2%, respectively. In the BIG 1-98 cohort, similar results were observed; for the interaction with subtype (p = .12), the adjusted HR of PR status for DRFI was 0.88 (95% CI, 0.57-1.35) in luminal A-like and 0.58 (95% CI, 0.43-0.77) in luminal B-like tumors. Observed 5-year cumulative incidences were similar. PR positivity may be more protective against metastatic relapse in luminal B-like versus luminal A-like breast cancer, but no strong conclusions can be made. In absolute risk, results suggest an absent PR is clinically more important in high compared with low proliferative ER+ HER-2 negative tumors. An absent progesterone receptor (PR) predicts a worse outcome in women treated for an estrogen receptor-positive, human epidermal growth factor receptor 2 negative breast cancer. As low proliferative tumors lacking PR are now also classified high risk, the prognostic value of PR across risk groups was studied. Despite a negative test for interaction of the prognostic value of PR by tumor grade, the magnitude of an absent PR on breast cancer relapse is much larger in high than in low proliferative breast cancers.

Abstract 1800: Progesterone receptor attenuates STAT1-mediated interferon signaling in breast cancer

Abstract Why some tumors remain indolent and others progress to clinical relevance remains a major unanswered question in cancer biology. Interferon signaling in nascent tumors, mediated by STAT1, is a critical step through which the surveilling immune system can recognize and destroy developing tumors, thereby blocking their progression. We used an unbiased approach aimed at identifying nuclear protein interactions, called RIME, to identify novel progesterone receptor (PR) protein-protein interactions in T47D breast cancer cells. Using this technique, we identified a novel interaction between PR and STAT1. This interaction led to decreased interferon-induced STAT1 phosphorylation, a phenotype that was further potentiated in the presence of PR ligand. In human breast cancer samples, PR-positive tumors exhibited lower levels of phospho-STAT1 as compared to their PR-negative counterparts, indicating that this phenotype translates to human tumors. Breast cancer cells lacking PR expression exhibited higher levels of interferon-stimulated gene (ISG) RNA, the transcriptional endpoint of interferon activation, indicating that unliganded PR alone could decrease transcription of ISGs. Moreover, the absence of PR led to increased recruitment of STAT1, STAT2 and IRF9 (key transcription factors necessary for ISG transcription) to ISG promoters. These data indicate that PR, both in the presence and absence of ligand, attenuates interferon-induced STAT1 signaling, culminating in significantly abrogated activation of genes transcribed in response to interferons. PR-positive tumors may use downregulation of STAT1-mediated interferon signaling to escape immune surveillance, leading to the development of clinically relevant PR-positive tumors. Selective immune evasion of PR-positive tumors may be one explanation as to why over 70% of breast cancers are PR-positive at the time of diagnosis. Citation Format: Merit Goodman, Gloria Trinca, Katherine Walter, Evangelia Papachristou, Clive D'Santos, Tianbao Li, Qi Liu, Zhao Lai, Prabhakar Chalise, Rashna Madan, Victor Jin, Jason Carroll, Christy Hagan. Progesterone receptor attenuates STAT1-mediated interferon signaling in breast cancer [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 1800.

Abstract 1259: Stem cell property-suppressing microRNAs are stimulated and their target proteins inhibited by vitamin D and progesterone in ovarian cancer cells

Abstract Vitamin D (1,25(OH)2D3) and progesterone (P4) have both been shown to reduce the incidence of ovarian cancer. Mechanisms involved in their actions are not fully known but each one can enhance the effect of the other. Six microRNAs (miRNAs), associated with suppression of cancer stem cell properties, were investigated first in a screening array and then with a more definitive RT-PCR investigation of the response of these miRNAs to 100 nM 1,25(OH)2D3 and 100 nM P4. These experiments were conducted in cells that do (OVCAR-3-PGR) and do not (SKOV3) express nuclear progesterone receptors (PGR). Let-7a and Let-7b are known to decrease expression of Ras and c-Myc and reduce stem cell self-renewal. Let-7b expression was increased (p&amp;lt;0.001) at 48 h in response to combined 1,25(OH)2D3 and P4 when PGR were present, and in response to individual and combined treatments at 72 h (p&amp;lt;0.01). Correspondingly, c-Myc expression was decreased (p&amp;lt;0.001) by both P4 and combined P4 and 1,25(OH)2D3. Let-7a expression was not affected by these treatments. No treatment-related change in the production of ras protein was observed compared to controls. In the absence of PGR (SKOV3 cells), c-Myc was suppressed by combined P4 and 1,25(OH)2D3 treatment at 24 h and 48 h. miR-26a and miR-101 are known to downregulate EpCAM and EZH2, leading to decreased invasion and metastasis and to reduced proliferation. miR-101 increased (p&amp;lt;0.001) at 48 h in response to combined 1,25(OH)2D3 and P4 in cells expressing PGR. It was increased (p&amp;lt;0.05) at 36 h and showed synergy in the screening array in the absence of PGR. Target proteins EZH2 and EpCAM decreased moderately (p&amp;lt;0.05) at 72 h combined treatment, both with and without PGR present. miR-26a expression was not affected by these treatments. miR-200b and miR-200c are known to suppress expression of ZEB1 which in turn decreases Bmi1 and Sox2 to increase E-cadherin (epithelial marker) and decrease vimentin (mesenchymal marker), thus inhibiting the epithelial-to-mesenchymal transition. Expression of miR-200b was increased (p&amp;lt;0.05) at 24 h and 72 h in response to P4 when PGR were present. miR-200c expression was not responsive to these treatments. ZEB1 was decreased (p&amp;lt;0.01) at 48 h in response to combined 1,25(OH)2D3 and P4. These results point not only to differences among cancer cell lines but they also emphasize a possible mechanism by which P4 and 1,25(OH)2D3 may work together to prevent the occurrence of ovarian cancer, namely by suppressing stem cell renewal and the formation of neoplastic lesions. The results also reveal that P4 may act via other signaling pathways than its primary nuclear receptors to effect suppression of stem cell properties. Increased expression of cancer stem cell-suppressing miRNAs may be an important mechanism mediating the efficacy of a progestin-based ovarian cancer prevention strategy. Citation Format: Rebecca Rosales, Jane Turbov, Jennifer Yoo, Gustavo C. Rodriguez, Larry G. Thaete. Stem cell property-suppressing microRNAs are stimulated and their target proteins inhibited by vitamin D and progesterone in ovarian cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1259. doi:10.1158/1538-7445.AM2017-1259

Long-term outcome of breast cancer patients with pathologic N3a lymph node stage

PurposeTo evaluate factors influencing the long-term outcome of patients presenting with 10 or more metastatic axillary lymph nodes (pN3a) after surgery for primary breast cancer. MethodBetween January 1990 and December 2015, a total of 130 patients with pN3a breast cancer at surgery were identified in our Institutions and included in the study. Twenty-nine of them (22.3%) received neoadjuvant chemotherapy. The Multivariate Cox proportional hazards model was used to determine independent prognostic factors associated with DFS and OS. ResultsAfter a median follow-up of 6.4 years (range 0.87–25 years), 2 patients had a local relapse, 59 distant metastases (1 with local relapse) and 52 patients died. The 5-year DFS and OS rates were 61.8% and 71.5%, respectively. At multivariate analysis, pN3a stage after neoadjuvant chemotherapy (ypN3a) was significantly associated with increased risk of recurrence (HR 1.92, p = 0.02) and death (HR 2.05, p = 0.029). Absence of progesterone receptor (PR) expression was the most important tumor characteristic associated with poor prognosis, both in terms of recurrence (HR 2.55, p < 0.001) and death (HR 2.23, p = 0.019). High levels of Ki-67 index (≥20%) were significantly associated with a shorter OS (HR 2.03, p = 0.027), but not with DFS. ConclusionsThe results of this study indicate that ypN3a stage, lack of expression of PR, and Ki-67 ≥ 20% negatively affect long-term outcome of patients with pN3a breast cancer.

Molecular alterations in indolent, aggressive and recurrent ovarian low-grade serous carcinoma.

The clinical courses of patients with low-grade serous carcinoma (LGSC) can be substantially different. The purpose of this study was to explore whether molecular or pathological features could identify patients who follow a more aggressive course. Twenty-six primary LGSCs (11 with an aggressive clinical course, and 15 with an indolent clinical course) and five paired recurrences were assessed for non-synonymous somatic mutations in 18 MAPK pathway genes and in 42 other classic cancer 'hotspot' genes by use of a custom-designed AmpliSeq panel based on the AmpliSeq Cancer hotspot panel v2. Copy number alterations for 94 target genes were assessed with the nCounter v2 Cancer CN assay. Immunohistochemistry for 12 proteins was performed. We detected 16 mutations in 13 of 26 cases (50%), affecting five genes that signal through the MAPK pathway, and one ESR1 mutation implicated in resistance to endocrine therapy in breast cancer. Recurrent samples were concordant with the primary tumour with respect to the mutational status, but all five cases showed additional alterations at the copy number or protein expression level. The absence of progesterone receptor (PR) expression and the presence of myometrial lymphovascular invasion were associated with an unfavourable outcome (log-rank P = 0.016 and P < 0.0001, respectively), but none of the other molecular features assessed showed an association. Despite limited case numbers, it appears that current molecular testing is inferior to a pathological parameter or protein expression in predicting the outcome of LGSCs. Prediction of outcome based on the primary tumour may be confounded by additional changes acquired over time.

Predictors of progestin therapy response in endometrial hyperplasia: An immunohistochemical study

Background: Women with endometrial hyperplasia have an elevated risk of endometrial carcinoma .The first line of treatment of endometrial hyperplasia in premenopausal women is progestin treatment with variable response. Objectives: To evaluate the predictive value of immunohistochemical (IHC) biomarkers in progestin treatment for cases having endometrial hyperplasia.Methods: A prospective trial was conducted among 50 premenopausal women with menometrorrhagia. Histopathological evaluation confirmed endometrial hyperplasia in pre-treatment endometrial biopsy [without atypia (n=43) and atypia (n=7)]. All patients treated with oral progestin for 3-6 months. Endometrial immunohistochemical examination for progesterone receptors, Bel-2 and p53 were analyzed in basal blocks.Results: Study participants were classified into two groups, Group One showed endometrial response (n = 38) and Group Two showed non-response or histological progression (n=12). Immunohistochemical expression was expressed as a histopathological immunoreactive score (IRS). Immunoreactive score for progesterone receptors were significant higher in responders. Absence of progesterone receptors and presence of p53 predicted non-responder status.Conclusions: Progesterone receptor expression may be a predictive biomarker of progestin response and p53 expression may be a predictive biomarker of progestin resistance.

Mechanism of action of the breast cancer-promoter hormone, 5α-dihydroprogesterone (5αP), involves plasma membrane-associated receptors and MAPK activation

Previous studies have shown that breast tissues and breast cell lines can convert progesterone to 5α-pregnane-3,20-dione (5aP), and that 5αP stimulates breast cell proliferation and detachment in vitro, and tumor formation in vivo, regardless of presence or absence of receptors for progesterone (PR) or estrogen (ER). Recently it was demonstrated, both in vitro and in vivo, that pro-cancer actions attributed to administered progesterone are due to the in situ produced 5αP. Because of the significant role of 5αP in breast cancers, it is important to understand its molecular mechanisms of action. The aims of the current studies were to identify 5αP binding sites and to determine if the mechanisms of action of 5αP involve the mitogen-activated protein kinase (MAPK), extracellular signal-regulated protein kinases (ERK1/2) pathway. Binding studies, using tritium-labeled 5αP ([3H]5αP), carried out on membrane, cytosol and nuclear fractions from human breast cells (MCF-7, PR/ER-positive; MDA-MB-231, PR/ER-negative) and on highly enriched membrane fractions, identified the plasma membrane as the site of ligand specific 5αP receptors. Localization of 5αP receptors to the cell membrane was confirmed visually with fluorescently labeled conjugate (5αP-BSA-FITC). Treatment of cells with either 5αP or membrane-impermeable 5αP-BSA resulted in significant increases in cell proliferation and detachment. 5αP and 5αP-BSA equally activated the MAPK/ERK1/2 pathway as evidenced by phosphorylation of ERK1/2. Inhibitors (PD98059, mevastatin and genistein) of specific sites along the Ras/Raf/MEK/ERK signaling pathway, blocked the phosphorylation and concomitantly inhibited 5αP-induced stimulation of cell proliferation and detachment. The study has identified high affinity, stereo-specific binding sites for 5αP that have the characteristics of a functional membrane 5αP receptor, and has shown that the cancer-promoter actions of 5αP are mediated from the liganded receptor via the MAPK/ERK1/2 signaling cascade. The findings enhance our understanding of the role of the progesterone metabolite 5αP in breast cancer and should promote new approaches to the development of breast cancer diagnostics and therapeutics.