ERα-36 regulates progesterone receptor activity in breast cancer.

BACKGROUND: Alterations in estrogen and progesterone signaling, via their respective receptors, estrogen receptor alpha (ERα) and progesterone receptor (PR), respectively, are largely involved in the development of breast cancer (BC). The recent identification of ERα-36, a splice variant of ERα, has uncovered a new facet of this pathology. Although ERα-36 expression is associated with poor prognosis, metastasis development, and resistance to treatment, its predictive value has so far not been associated with a BC subtype and its mechanisms of action remain understudied. METHODS: To study ERα-36 expression in BC specimens, we performed immunochemical experiments. Next, the role of ERα-36 in progesterone signaling was investigated by generating KO clones using the CRISPR/CAS9 technology. PR signaling was also assessed by proximity ligation assay, Western blotting, RT-QPCR, and ChIP experiments. Finally, proliferation assays were performed with the IncuCyte technology and migration experiments using scratch assays. RESULTS: Here, we demonstrate that ERα-36 expression at the plasma membrane is correlated with a reduced disease-free survival in a cohort of 160 BC patients, particularly in PR-positive tumors, suggesting a crosstalk between ERα-36 and PR. Indeed, we show that ERα-36 interacts constitutively with PR in the nucleus of tumor cells. Moreover, it regulates PR expression and phosphorylation on key residues, impacting the biological effects of progesterone. CONCLUSIONS: ERα-36 is thus a regulator of PR signaling, interfering with its transcriptional activity and progesterone-induced anti-proliferative effects as well as migratory capacity. Hence, ERα-36 may constitute a new prognostic marker as well as a potential target in PR-positive BC

Immunotherapeutic Approaches in Triple-Negative Breast Cancer: State of the Art and Future Perspectives

Triple-negative breast cancer (TNBC) is characterized by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). It accounts for 15%–20% of all breast cancers and is associated with an aggressive evolution and poor outcomes with the majority of recurrences and deaths occurring in the first 5 years. Chemotherapy remains the mainstay of treatment in the absence of effective targets, but the good understanding of immune tumor microenvironment, the identification of immune-related targets, and the role of tumor-infiltrating lymphocytes (TILs) in TNBC has allowed to develop promising immunotherapeutic strategies for this unique subset of breast cancer. Recently, immunotherapy is being extensively explored in TNBC and clinical trials have shown promising results. In this article, we tried to explain the rationale and mechanisms of targeting the immune system in TNBC, to report the results from recent clinical trials that put immunotherapy as a new standard of care in TNBC in addition to ongoing trials and future directions in the next decade

Molecular patterns of egyptian patients with non-squamous non-small-cell lung cancers: a clinicopathological study

Abstract Background Driver molecular aberrations, such as epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) gene rearrangement, play an important role in the oncogenesis and progression of non-squamous non-small-cell lung cancers (NSCLC). Therefore, this study aimed to detect the incidence of driver mutations among non-squamous NSCLC. Patients and methods This was a retrospective-prospective cohort study on 131 patients with non-squamous NSCLC. Data on age, smoking status, chest symptoms, method of lung cancer diagnosis, molecular testing, including EGFR mutations in formalin-fixed paraffin-embedded (FFPE) tumor tissue and serum circulating tumor DNA using next-generation sequencing and ALK gene rearrangement by FFPE tumor tissue, and follow-up data regarding treatment modalities and outcomes were collected. Results The median age of the patients was 57 years (range: 32–79 years). Out of 131 patients, 97 were males (74%), and 90 (68.7%) were smokers. Among 128 patients tested, 16 (12.5%) had EGFR mutations detected with either technique by formalin-fixed paraffin-embedded (FFPE) tumor tissue or/and serum circulating tumor DNA using next-generation sequencing, and 6 (4.7%) had ALK rearrangement by FFPE tumor tissue. The majority (62.6%) presented with metastatic disease. Among the 102 patients who received first-line systemic therapy, the objective response rate was 50.0% in mutated NSCLC versus 14.6% in non-mutated (p < 0.001). Among the eight mutated patients who received first-line tyrosine kinase inhibitors (TKIs), 7 patients achieved either complete response or partial response. Among the 22 mutated patients, the median overall survival was 3 months in those who did not receive targeted therapy versus not reached in those who received any type of targeted therapy (p < 0.001). Conclusion Screening patients with newly diagnosed non-squamous NSCLC for driver mutations is essential for major prognostic and therapeutic implications. Early administration of TKIs in mutated patients significantly improves disease outcomes

Analysis of PI3K/mTOR Pathway Biomarkers and Their Prognostic Value in Women with Hormone Receptor–Positive, HER2-Negative Early Breast Cancer

BACKGROUND: The PI3K/AKT/mTOR pathway alterations have been shown to play significant roles in the development, progression, and metastatic spread of breast cancer. Furthermore, they have been implicated in the process of drug resistance, especially endocrinal therapies. In this study, we aimed to define the correlation between the PI3K mutations and the expression of the phosphorylated forms of different downstream molecules in women with estrogen receptor (ER)–positive, human epidermal growth factor receptor 2–negative (luminal) early breast cancer treated at Cairo university hospitals. METHODS: Next-generation sequencing was used to detect mutations in the PIK3CA hotspots (in exons 9 and 20). Immunohistochemistry was performed on tissue microarray blocks prepared from samples of 35 Egyptian luminal breast cancer patients in the pathology department of Centre Léon Bérard (CLB). The intensity and the percentage of stained tumor cells were integrated to define high versus low biomarker expression. The cytoplasmic and nuclear stainings were graded separately. Patients were followed for a median of 4.7 years (2.1 to 6.9 years). Correlation was done between PI3K mutations and the immunohistochemistry expression of pAKT, LKB1, p4EBP1, and pS6 ribosomal protein (pS6RP) with the clinicopathologic features and disease free survival (DFS) of the patients. RESULTS: Median age at diagnosis was 51.3 years (range, 25 to 82 years). Tumors were larger than 20 mm in 79.2% of the cases, whereas 57.9% had axillary lymph node deposits. Only 12.3% of the patients had SBR grade I tumors, 50.8% had grade II, and 36.8% had grade III. ERs were negative in 6 patients (17%) after pathology review. Thirty-two cases were assessable for LKB1 and pAKT, 33 for p4EBP1 and pS6RP, and 24 for PI3K mutations. Nuclear LKB1, cytoplasmic LKB1, nuclear pAKT, cytoplasmic pAKT, nuclear p4EBP1, and cytoplasmic pS6RP expression was high in 65.6%, 62.5%, 62.5%, 68.8%, 42.4%, and 57.6%, respectively. PIK3CA mutations were found in 7 patients (29.2%). PI3K mutations were correlated with nuclear localization of pAKT (i.e., decreased cytoplasmic pAKT, P = .04; and increased nuclear pAKT, P = .10). There was a tendency toward an inverse correlation between PI3K mutations and the expression of pS6RP (P = .10) and p4EBP1 (P = .19). Nuclear LKB1 expression was a marker of good prognosis. It was associated with smaller tumors (P = .05), more ER (P = .08) and progesteron receptor (PgR) positivity (P = .002). In the Kaplan Meier (KM) model, patients with high nuclear LKB1 had longer DFS (hazard ratio = 0.36; 95% confidence interval, 0.15-1.10; P = .08). Nuclear pAKT high expression also carried a tendency toward longer DFS (hazard ratio = 0.51; 95% confidence interval, 0.11-1.16; P = .13). The expression of p4EBP1, pS6RP, and the PI3K mutational status did not show any prognostic significance in our cohort. CONCLUSION: Among the studied biomarkers, only nuclear expression of LKB1 and pAKT tended to predict better survival in breast cancer patients. PI3K mutation was correlated with the expression of nuclear pAKT but not pS6RP or p4EBP1

The relationship between coping self-efficacy and B cells in breast cancer patients

Abstract Background Breast cancer is the most common tumor among women throughout the world. Diagnosis and treatment of breast cancer are associated with stress and depression. Self-efficacy is one of the most important personal characteristics, studied in cancer, and is correlated with depression and immunity. The aim of the study is as follows: 1. Examining the correlation between coping self-efficacy with depression, DHEA levels, and immunity 2. Examining the correlation between depression and DHEA levels 3. Studying the effect of depression and DHEA levels on immunity 4. Examining the intermediate effect of DHEA levels on the correlation between coping self-efficacy and immunity Methods Thirty newly diagnosed breast cancer patients recruited from the Oncology Department, Kasr EL-Aini, Cairo University (ages 51.40 + 8.24 years) responded to two questionnaires: Coping Self-Efficacy Scale (CSES) and Patient Health Questionnaire-9 (PHQ-9); blood samples were collected to measure the phenotype of patients’ cellular immunity and DHEA levels by flowcytometry and ELISA technique. Results There was a significant negative correlation between CSES and PHQ-9, a significant positive correlation between PHQ-9 and B-cell count, and there is a significant negative correlation between CSES and B-cell count. The presence of DHEA has no mediatory role on correlation between CSES and B-cell count. Conclusion This paper presents a new model of psychoneuroimmunology by suggesting an effect of coping self-efficacy on immunity against breast cancer patients

LKB1 regulates PRMT5 activity in breast cancer

International audienceProtein arginine methyltransferase 5 (PRMT5) is the main enzyme responsible for the symmetrical dimethylation of arginine residues on target proteins in both the cytoplasm and the nucleus. Though its activity has been associated with tumor progression in various cancers, the expression pattern of this oncoprotein has been scarcely studied in breast cancer. In the current work, we analyzed its expression in a large cohort of breast cancer patients, revealing higher nuclear PRMT5 levels in ERα-positive tumors and an association with prolonged disease free and overall survival. Interestingly, high PRMT5 nuclear expression was also associated with higher nuclear liver kinase B1 (LKB1), suggesting that a functional relationship may occur. Consistently, several approaches provided evidence that PRMT5 and LKB1 interact directly in the cytoplasm of mammary epithelial cells. Moreover, although PRMT5 is not able to methylate LKB1, we found that PRMT5 is a bona fade substrate for LKB1. We identified T132, 139 and 144 residues, located in the TIM-Barrel domain of PRMT5, as target sites for LKB1 phosphorylation. The point mutation of PRMT5 T139/144 to A139/144 drastically decreased its methyltransferase activity, due probably to the loss of its interaction with regulatory proteins such as MEP50, pICln and RiOK1. In addition, modulation of LKB1 expression modified PRMT5 activity, highlighting a new regulatory mechanism that could have clinical implications