Hasil untuk "Cytology"

Di Xiao, Jia Yao, Xin Yang et al.

Abstract EGFR, one of the most successful therapeutic targets, has recently been found to exert a novel function for regulating homologous recombination (HR). Activation of HR is the critical event of treatment failure of PARPi in BRCA1/2 wild-type ovarian cancer (OC). Besides, the antitumor effects of biguanides have also been a focus of attention. Here, we discovered that the new biguanide 4C inhibited HR and sensitized BRCA1/2 wild-type OC cells to PARPi by targeting EGFR. Mechanistically, EGFR promoted nuclear accumulation of both BRCA2 and Rad51, and HR activation by competitively inhibiting the binding of BRCA2 and Rad51 to E3 ubiquitin ligase c-Cbl, thereby reducing cancer cell sensitivity to PARPi following ATM-mediated DNA damage signal transmission from the nucleus to the cytoplasm. Interestingly, EGFR was downregulated by 4C, which in turn enhanced the interaction of BRCA2 and Rad51 with c-Cbl. Consequently, BRCA2 and Rad51 were then ubiquitinated and degraded to inhibit HR and increase the sensitivity of OC to PARPi. Thus, these findings reveal that the combination of 4C with PARPi leading to “synthetic lethality” is an effective strategy for treating BRCA1/2 wild-type OC.

Mahmoud Zhra, Muhammad Affan Elahi, Aamira Tariq et al.

Metabolic dysfunction leading to non-alcoholic fatty liver disease (NAFLD) exhibits distinct molecular and immune signatures that are influenced by factors like gut microbiota. The gut microbiome interacts with the liver via a bidirectional relationship with the gut–liver axis. Microbial metabolites, sirtuins, and immune responses are pivotal in different metabolic diseases. This extensive review explores the complex and multifaceted interrelationship between sirtuins and gut microbiota, highlighting their importance in health and disease, particularly metabolic dysfunction and hepatocellular carcinoma (HCC). Sirtuins (SIRTs), classified as a group of NAD⁺-dependent deacetylases, serve as crucial modulators of a wide spectrum of cellular functions, including metabolic pathways, the inflammatory response, and the process of senescence. Their subcellular localization and diverse functions link them to various health conditions, including NAFLD and cancer. Concurrently, the gut microbiota, comprising diverse microorganisms, significantly influences host metabolism and immune responses. Recent findings indicate that sirtuins modulate gut microbiota composition and function, while the microbiota can affect sirtuin activity. This bidirectional relationship is particularly relevant in metabolic disorders, where dysbiosis contributes to disease progression. The review highlights recent findings on the roles of specific sirtuins in maintaining gut health and their implications in metabolic dysfunction and HCC development. Understanding these interactions offers potential therapeutic avenues for managing diseases linked to metabolic dysregulation and liver pathology.

Tom Schimanski, Rafael Loucas, Marios Loucas et al.

Background: Mechanical processing techniques are commonly employed to prepare adipose tissue for clinical applications in reconstructive and aesthetic procedures. However, their histological and immunohistochemical impact on adipose tissue remains incompletely characterized. Purpose: This systematic review aims to investigate the impact of mechanical processing on the histological and immunohistochemical properties of adipose tissue. Methods: A systematic search was conducted using PubMed, Ovid, and Cochrane Library databases, with publications up to December 2024, employing Boolean operators (“mechanically processed” OR “lipoaspirate” OR “fat graft” OR “gauze rolling” OR “decantation” OR “coleman fat” OR “celt” OR “nanofat” OR “lipofilling” OR “human fat”) AND (“histol*”). Included were English-language studies or studies with a recognized English translation which had been subject to peer review and reported quantitative or qualitative markers of mechanically processed human adipose tissue with histology or immunohistochemistry. Risk of Bias was assessed with the OHAT score. Results: A total of 15 studies (<i>n</i> = 15) were included. In 13 of 15 studies (87%), mechanically processed adipose tissue demonstrated an increased stromal vascular fraction (SVF) cell density compared to unprocessed fat. Twelve studies (80%) reported improved preservation of the extracellular matrix (ECM), while 11 studies (73%) observed a reduction in mature adipocytes. Immunohistochemical analyses in 10 studies (67%) revealed elevated expression of vascular markers (CD31, CD34) and perilipin. Adverse histological features such as oil cysts, fibrosis, and inflammatory infiltrates were reduced in 9 studies (60%). Considerable heterogeneity in processing techniques and staining protocols precluded meta-analysis. Conclusions: Mechanical processing of adipose tissue is associated with favorable histological and immunohistochemical profiles, including increased SVF cell density, improved ECM preservation, and reduced inflammatory and fibrotic features. These findings support the potential of mechanical processing to enhance graft quality; however, standardization of techniques and evaluation protocols is needed to strengthen clinical translation.

Danilo Mladenović, Joseph Brealey, Ben Peacock et al.

Abstract Current state‐of‐the‐art tools for analysing extracellular vesicles (EVs) offer either highly sensitive but unidimensional bulk measurements of EV components, or high‐resolution multiparametric single‐particle analyses which lack standardization and appropriate reference materials. This limits the accuracy of the assessment of marker abundance and overall marker distribution amongst individual EVs, and finally, the understanding of true EV heterogeneity. In this study, we aimed to define the standardized operating procedures and reference material for fluorescent characterization of EVs with two commonly used EV analytical platforms—nanoparticle tracking analysis (NTA) and nano‐flow cytometry (nFCM). We achieved quantitative fluorescence analyses on ZetaView NTA and NanoAnalyzer nFCM instruments, by utilizing yellow‐green FluoSpheres (FS) with assigned ERF (equivalent reference fluorophore) values. This standardization technique allowed for fluorescent EV signal to be expressed in ERF units (indicative of bound fluorescent antibodies per EV), thus enabling measurement of target protein marker abundance on individual EVs, and in the whole EV population. The NTA's and nFCM's limits of detection (LoD) were evaluated at 21 and 9 Alexa Fluor 488 (AF488) molecules, respectively. To complement the limited quantification of markers expressed in a few copies per single EV, in‐line bulk fluorescence measurements with a plate reader were performed. This provided absolute marker quantification and more insightful analyses of EV heterogeneity and marker stoichiometry. The standardization method outlined in this work unlocks the full analytical potential of NTA and nFCM, enabling cross‐platform data comparison. At the same time, it highlights some of the technical challenges and considerations and thus contributes to the ongoing efforts towards the development of EV analytical tools.

Ke-jie Wang, Sha-zhou Ye, Xiao-long Jia et al.

Abstract The RON receptor tyrosine kinase is critical in the pathogenesis of various cancer types, however, its role in bladder cancer invasive growth is still largely unknown. Here, we found that over 90% of bladder cancer samples exhibit elevated levels of RON expression, with significantly higher expression levels observed in invasive bladder cancer compared to non-invasive bladder cancer. In vitro, RON activation resulted in increased bladder cancer cell migration and invasiveness. Results from mRNA sequencing and transcriptome analysis further demonstrated that MMP12, a downstream molecule of RON, is functionally involved in regulating RON-mediated bladder cancer cell migration and invasiveness. The underlying mechanism appeared to be the RON-mediated inhibition of HIF-2α ubiquitination, which is channeled through the activation of the JNK signaling pathway. Consequently, the activated JNK pathway increased MMP12 expression, ultimately driving bladder cancer cell migration and invasion. As evident in bioinformatics and dual-luciferase reporter assays, the RON mRNA at its 3′-untranslated regions specifically interacted with hsa-miR-659-3p. The binding of hsa-miR-659-3p downregulated the RON gene expression, attenuating the receptor-mediated tumorigenic activities of bladder cancer cells in vitro and in vivo. In conclusion, aberrant RON expression in bladder cancer cells and MMP12 and HIF-2α activities form a functional axis that causes increased bladder cancer cell migration and invasion. The fact that hsa-miR-659-3p downregulates RON expression indicates its critical role in attenuating RON-mediated tumorigenic effect on bladder cancer cells. These findings highlight the importance of RON targeting as a therapeutic means for potential bladder cancer therapy.

Chiara Gentili, Maria Elisabetta Federica Palamà, Gillian Sexton et al.

The current gold standard grafting material is autologous bone due to its osteoinductive and osteoconductive properties. Autograft harvesting results in donors site morbidity. Coral scaffolds offer a natural autograft alternative, sharing the density and porosity of human bone. This study investigated the biocompatibility and osteogenic potential of a novel, sustainably grown Pocillopora scaffold with human bone marrow-derived mesenchymal stromal cells (MSCs). The coral-derived scaffold displays a highly textured topography, with concavities of uniform size and a high calcium carbonate content. Large scaffold samples exhibit compressive and diametral tensile strengths in the range of trabecular bone, with strengths likely increasing for smaller particulate samples. Following the in vitro seeding of MSCs adjacent to the scaffold, the MSCs remained viable, continued proliferating and metabolising, demonstrating biocompatibility. The seeded MSCs densely covered the coral scaffold with organized, aligned cultures with a fibroblastic morphology. In vivo coral scaffolds with MSCs supported earlier bone and blood vessel formation as compared to control constructs containing TCP-HA and MSCs. This work characterized a novel, sustainably grown coral scaffold that was biocompatible with MSCs and supports their in vivo osteogenic differentiation, advancing the current repertoire of biomaterials for bone grafting.

Yan-Wen Wang, Poh-Ching Tan, Qing-Feng Li et al.

Abstract To clarify the protective effects of subcutaneous adipose tissue (SAT) against photodamage, we utilized nude mouse skin with or without SAT. Skin and fibroblasts were treated with adipose tissue-derived extracellular vesicles (AT-EVs) or extracellular vesicles derived from adipose-derived stem cells (ADSC-EVs) to demonstrate that SAT protects the overlying skin from photodamage primarily through AT-EVs. Surprisingly, AT-EVs stimulated fibroblast proliferation more rapidly than ADSC-EVs did. The yield of AT-EVs from the same volume of AT was 200 times greater than that of ADSC-EVs. To compare the differences between AT-EVs and ADSC-EVs, we used a proximity barcoding assay (PBA) to analyze the surface proteins on individual particles of these two types of EVs. PBA analysis revealed that AT-EVs contain diverse subpopulations, with 83.42% expressing CD151, compared to only 1.98% of ADSC-EVs. Furthermore, AT-EVs are internalized more rapidly by cells than ADSC-EVs, as our study demonstrated that CD151-positive AT-EVs were endocytosed more quickly than their CD151-negative counterparts. Additionally, adiponectin in AT-EVs activated the AMPK pathway and inhibited the NF-κB pathway, enhancing fibroblast protection against photodamage. The significantly higher yield and faster acquisition of AT-EVs compared to ADSC-EVs underscore their potential for broader applications. Graphical Abstract AT mitigates skin photoaging via AT-EVs, which consist of 14 subpopulations and express more CD151 and APN on their surface, as determined by PBA sequencing. CD151 facilitates faster cellular recognition and uptake of AT-EVs. APN activates AdipoR to stimulate the AMPK pathway and inhibit the NF-κB pathway, reducing ROS and DNA damage in fibroblasts. This results in improved skin histology, increased collagen production, a reduction in senescent cells, and decreased ROS accumulation. (Created with BioRender.com)

Min Yang, Ying Zhang, Min Li et al.

Abstract After skin malignancy, breast cancer is the most widely recognized cancer detected in women in the United States. Breast cancer (BCa) can happen in all kinds of people, but it's much more common in women. One in four cases of cancer and one in six deaths due to cancer are related to breast cancer. Angiogenesis is an essential factor in the growth of tumors and metastases in various malignancies. An expanded level of angiogenesis is related to diminished endurance in BCa patients. This function assumes a fundamental part inside the human body, from the beginning phases of life to dangerous malignancy. Various factors, referred to as angiogenic factors, work to make a new capillary. Expanding proof demonstrates that angiogenesis is managed by microRNAs (miRNAs), which are small non-coding RNA with 19–25 nucleotides. MiRNA is a post-transcriptional regulator of gene expression that controls many critical biological processes. Endothelial miRNAs, referred to as angiomiRs, are probably concerned with tumor improvement and angiogenesis via regulation of pro-and anti-angiogenic factors. In this article, we reviewed therapeutic functions of miRNAs in BCa angiogenesis, several novel delivery carriers for miRNA-based therapeutics, as well as CRISPR/Cas9 as a targeted therapy in breast cancer.

Juliana Haydeé Enriqué Steinberg, Fabiana Alejandra Rossi, Roberto Magliozzi et al.

Abstract Triple-negative breast cancer (TNBC) is a subtype of breast cancer associated with metastasis, high recurrence rate, and poor survival. The basic helix-loop-helix transcription factor SHARP1 (Split and Hairy-related Protein 1) has been identified as a suppressor of the metastatic behavior of TNBC. SHARP1 blocks the invasive phenotype of TNBC by inhibiting hypoxia-inducible factors and its loss correlates with poor survival of breast cancer patients. Here, we show that SHARP1 is an unstable protein that is targeted for proteasomal degradation by the E3 ubiquitin ligase complex SCFβTrCP. SHARP1 recruits βTrCP via a phosphodegron encompassing Ser240 and Glu245 which are required for SHARP1 ubiquitylation and degradation. Furthermore, mice injected with TNBC cells expressing the non-degradable SHARP1(S240A/E245A) mutant display reduced tumor growth and increased tumor-free survival. Our study suggests that targeting the βTrCP-dependent degradation of SHARP1 represents a therapeutic strategy in TNBC.

Fang Cao, Yunpeng Jiang, Lin Chang et al.

Abstract Pancreatic cancer is a leading cause of cancer death due to its early metastasis and limited response to the current therapies. Metastasis is a complicated multistep process, which is determined by complex genetic alterations. Despite the identification of many metastasis-related genes, distinguishing the drivers from numerous passengers and establishing the causality in cancer pathophysiology remains challenging. Here, we established a high-throughput and piggyBac transposon-based genetic screening platform, which enables either reduced or increased expression of chromosomal genes near the incorporation site of the gene search vector cassette that contains a doxycycline-regulated promoter. Using this strategy, we identified YWHAZ as a key regulator of pancreatic cancer metastasis. We demonstrated that functional activation of Ywhaz by the gene search vector led to enhanced metastatic capability in mouse pancreatic cancer cells. The metastasis-promoting role of YWHAZ was further validated in human pancreatic cancer cells. Overexpression of YWHAZ resulted in more aggressive metastatic phenotypes in vitro and a shorter survival rate in vivo by modulating epithelial-to-mesenchymal transition. Hence, our study established a high-throughput screening method to investigate the functional relevance of novel genes and validated YWHAZ as a key regulator of pancreatic cancer metastasis.

Martyna Trzeszcz, Maciej Mazurec, Robert Jach et al.

Recently, cervical cancer rates elevation has been noted in women aged 20–39 years in regions with a very high human development index (HDI). The onset of cancer elevation rates is observed in the age range of 25–29 years, which should necessitate effective precancer screening in younger age groups, including those <25 years. From 30.066 liquid-based screening tests results (<i>n</i> = 30.066), 3849 liquid-based cytology, 1321 high-risk human papillomavirus (HRHPV) and 316 p16/Ki67 performed in women <30 years were selected. Performance characteristics were calculated for three screening models: primary HRHPV with p16/Ki67 triage, primary cytology with reflex HPV and primary cytology alone. Primary HRHPV with p16/Ki67 triage was significantly more sensitive in high-grade squamous intraepithelial lesion quantified with cervical intraepithelial neoplasia grade 2 or worse [HSIL(CIN2+)] detection than cytology with reflex HRHPV and cytology alone (83.3% vs. 70.8%/45.8%) and had significantly higher diagnostic predictive values (PPV:29.4%/21.3%/22.9%; NPV:91.7%/82.9%/82.2%, respectively at CIN2+ threshold). The number of colposcopies per HSIL(CIN2+) detection indices was 3.4, 4.7 and 4.4, respectively. Primary HPV testing in women <30 years with p16/Ki67 triage of HPV-positive cases might be an effective cervical cancer screening strategy for HSIL(CIN2+) detection with superior diagnostic performance when compared with primary cytology-based models. Women <25 years might also benefit from an introduction to a more sensitive screening approach.

Masaaki Yano, Alessandro Nasti, Akihiro Seki et al.

Introduction: Freshly isolated uncultured adipose tissue-derived stromal cells (u-ADSCs), containing miscellaneous cells like the relatively abundant mesenchymal stem cells, are attractive for repair and regenerative therapy. However, the detailed characteristics and therapeutic efficacy of u-ADSCs obtained from disease-affected hosts are unknown. We compared the properties of u-ADSCs obtained from wild-type mice and from a mouse model of non-alcoholic steatohepatitis (NASH). Methods: The NASH model was established by feeding C57BL/6J mice an atherogenic high-fat diet for 4 (NASH (4w)) or 12 weeks (NASH (12w)), followed by the isolation and characterization of u-ADSCs. Wild-type u-ADSCs or NASH-derived u-ADSCs were administered to mice with NASH cirrhosis, followed by analyses of hepatic inflammatory cells, antigen profiles, fibrosis, and gene expression. Results: Wild-type u-ADSCs and NASH-derived u-ADSCs did not show marked differences in surface antigen profiles. In NASH (4w) u-ADSCs, but not NASH (12w) u-ADSCs, the frequencies of the leukocyte markers CD11b, CD45, and CD44 were elevated; furthermore, we observed an increase in the M1/M2 macrophage ratio only in NASH (12w) u-ADSCs. Only in NASH-4w u-ADSCs, the expression levels cell cycle-related genes were higher than those in u-ADSCs. Wild-type u-ADSCs administered to mice with NASH-related cirrhosis decreased the infiltration of CD11b+, F4/80+, and Gr-1+ inflammatory cells, ameliorated fibrosis, and had a restorative effect on liver tissues, as determined by gene expression profiles and the NAFLD activity score. The therapeutic effects of NASH (4w) u-ADSCs and NASH (12w) u-ADSCs on NASH-related cirrhosis were highly similar to the effect of wild-type u-ADSCs, including reductions in inflammation and fibrosis. Conclusions: NASH-derived u-ADSCs, similar to wild-type u-ADSCs, are applicable for reparative and regenerative therapy in mice with NASH.

Yewlin E. Chee, Raghu Mudumbai, Steven S. Saraf et al.

Purpose: To describe two cases of medium-sized uveal melanoma presenting with hemorrhagic choroidal detachments. Observations: The first case is a 39-year-old man who presented with choroidal hemorrhage and angle closure glaucoma. The second case is a 42-year-old man who presented with choroidal hemorrhage and posterior scleritis. Vitrectomy with transvitreous fine needle aspiration biopsy was ultimately required to diagnose malignant uveal melanoma in each case. Conclusions and importance: Intraocular hemorrhage is a rare presenting sign of uveal melanoma. When it does occur, it is typically associated with large tumors. Hemorrhagic choroidal detachments are particularly rare in uveal melanoma, and can limit the diagnostic utility of clinical exam, B-scan ultrasonography, and magnetic resonance imaging. Although it is uncommon, it is important to maintain a high index of suspicion for choroidal melanoma in any patient with unexplained choroidal hemorrhage.

Lauren A. Poppi, Khue Tu Ho-Nguyen, Anna Shi et al.

Cholinergic interneurons are “gatekeepers” for striatal circuitry and play pivotal roles in attention, goal-directed actions, habit formation, and behavioral flexibility. Accordingly, perturbations to striatal cholinergic interneurons have been associated with many neurodevelopmental, neurodegenerative, and neuropsychiatric disorders. The role of acetylcholine in many of these disorders is well known, but the use of drugs targeting cholinergic systems fell out of favor due to adverse side effects and the introduction of other broadly acting compounds. However, in response to recent findings, re-examining the mechanisms of cholinergic interneuron dysfunction may reveal key insights into underlying pathogeneses. Here, we provide an update on striatal cholinergic interneuron function, connectivity, and their putative involvement in several disorders. In doing so, we aim to spotlight recurring physiological themes, circuits, and mechanisms that can be investigated in future studies using new tools and approaches.

Wulf Palinski, Maria Monti, Rosa Camerlingo et al.

Abstract The tumor microenvironment modulates cancer growth. Extracellular vesicles (EVs) have been identified as key mediators of intercellular communication, but their role in tumor growth is largely unexplored. Here, we demonstrate that EVs from sarcoma patients promote neoangiogenesis via a purinergic X receptor 4 (P2XR4) -dependent mechanism in vitro and in vivo. Using a proteomic approach, we analyzed the protein content of plasma EVs and identified critical activated pathways in human umbilical vein endothelial cells (HUVECs) and human progenitor hematopoietic cells (CD34+). We then showed that vessel formation was due to rapid mitochondrial activation, intracellular Ca2+ mobilization, increased extracellular ATP, and trafficking of the lysosomal P2XR4 to the cell membrane, which is required for cell motility and formation of stable branching vascular networks. Cell membrane translocation of P2XR4 was induced by proteins and chemokines contained in EVs (e.g. Del-1 and SDF-1). Del-1 was found expressed in many EVs from sarcoma tumors and several tumor types. P2XR4 blockade reduced EVs-induced vessels in angioreactors, as well as intratumor vascularization in mouse xenografts. Together, these findings identify P2XR4 as a key mediator of EVs-induced tumor angiogenesis via a signaling mediated by mitochondria-lysosome-sensing response in endothelial cells, and indicate a novel target for therapeutic interventions.

Nao Nishida-Aoki, Naoomi Tominaga, Nobuyoshi Kosaka et al.

Extracellular vesicles (EVs) from cancer are delivered both proximal and distal organs. EVs are highly glycosylated at the surface where EVs interact with cells and therefore has an impact on their properties and biological functions. Aberrant glycosylation in cancer is associated with cancer progression and metastasis. However, the biological function of glycosylation on the surface of EV is uncovered. We first demonstrated differential glycosylation profiles of EVs and their originated cells, and distinct glycosylation profiles in a brain-metastatic subline BMD2a from its parental human breast cancer cell line, MDA-MB-231-luc-D3H2LN by lectin blot. We then investigated the roles of surface glycoconjugates on EV uptake. N- and/or O-glycosylation removal of fluorescent-labelled BMD2a EVs enhanced cellular uptake to endothelial cells, suggesting that surface glycosylation has inhibitory effects on cellular uptake. Biodistribution of glycosylation-deprived BMD2a EVs administrated intravenously into mice was further analysed ex vivo using near-infrared lipophilic dye. EVs treated with O-deglycosylation enzymes enhanced the accumulation of EVs to the lungs after 24 h from the injection, while N-deglycosylation did not markedly alter biodistribution. As the lungs are first organs in which intravenous blood flows, we suggest that surface glycosylation of cancer-derived EVs avoid promiscuous adhesion to proximal tissues to be delivered to distant organs.

Erika Hilbold, Ottmar Distl, Martina Hoedemaker et al.

Male factor infertility is a problem in today&#8217;s society but many underlying causes are still unknown. The generation of a conditional Sertoli cell (SC)-specific connexin 43 (Cx43) knockout mouse line (SCCx43KO) has provided a translational model. Expression of the gap junction protein Cx43 between adjacent SCs as well as between SCs and germ cells (GCs) is known to be essential for the initiation and maintenance of spermatogenesis in different species and men. Adult SCCx43KO males show altered spermatogenesis and are infertile. Thus, the present study aims to identify molecular mechanisms leading to testicular alterations in prepubertal SCCx43KO mice. Transcriptome analysis of 8-, 10- and 12-day-old mice was performed by next-generation sequencing (NGS). Additionally, candidate genes were examined by qRT-PCR and immunohistochemistry. NGS revealed many significantly differentially expressed genes in the SCCx43KO mice. For example, GC-specific genes were mostly downregulated and found to be involved in meiosis and spermatogonial differentiation (e.g., <i>Dmrtb1</i>, <i>Sohlh1</i>). In contrast, SC-specific genes implicated in SC maturation and proliferation were mostly upregulated (e.g., <i>Amh</i>, <i>Fshr</i>). In conclusion, Cx43 in SCs appears to be required for normal progression of the first wave of spermatogenesis, especially for the mitosis-meiosis switch, and also for the regulation of prepubertal SC maturation.

Pranab Dey

Pranab Dey

Angela Maselli, Stefania Parlato, Rossella Puglisi et al.

Tamoxifen resistance is a major hurdle in the treatment of estrogen receptor (ER)-positive breast cancer. The mechanisms of tamoxifen resistance are not fully understood although several underlying molecular events have been suggested. Recently, we identified autoantibodies reacting with membrane-associated ER&#945; (anti-ER&#945; Abs) in sera of breast cancer patients, able to promote tumor growth. Here, we investigated whether anti-ER&#945; Abs purified from sera of ER-positive breast cancer patients could contribute to tamoxifen resistance. Anti-ER&#945; Abs inhibited tamoxifen-mediated effects on cell cycle and proliferation in MCF-7 cells. Moreover, anti-ER&#945; Abs hampered the tamoxifen-mediated reduction of tumor growth in SCID mice xenografted with breast tumor. Notably, simvastatin-mediated disaggregation of lipid rafts, where membrane-associated ER&#945; is embedded, restored tamoxifen sensitivity, preventing anti-ER&#945; Abs effects. In conclusion, detection of serum anti-ER&#945; Abs may help predict tamoxifen resistance and concur to appropriately inform therapeutic decisions concerning hormone therapy in ER-positive breast cancer patients.