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1.
J Inflamm Res ; 17: 3815-3823, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895142

RESUMO

Purpose: Periductal mastitis (PDM) is a chronic inflammatory lesion of the breast with an unknown etiology, and it is difficult for clinicians to differentiate it from granulomatous lobular mastitis (GLM), although they have different treatment strategies and prognosis. This study aimed to investigate the differences in their clinicopathologic features to inform treatment strategies. Patients and Methods: Between 2011 and 2020, 121 patients diagnosed with PDM and 57 patients with GLM were retrospective analysis. Patient data were extracted on demographics, clinical presentation, pathologic characteristics, treatments and clinical response. Histopathological evaluations were performed on core needle biopsy specimens. Immunohistochemical stains using antibodies against CD3, CD4, CD8, CD20, and CD138 was performed to define immune cell infiltration. Results: PDM patients had a higher median age compared to GLM patients (38 vs 32, p<0.001). PDM was primarily located in the areolar area, while GLM predominantly affected the peripheral quadrant of the breast (56.20% vs 75.44%, p<0.001). Histopathologically, more ductal dilatation (90.08% vs 3.51%, p<0.001), ductal wall thickening (47.93% vs 1.75%, p<0.001), and ductal rupture (44.63% vs 5.26%, p<0.001) were observed in PDM. GLM presented with significantly more granuloma (94.74% vs 10.74%, p<0.001), microabscess (68.42% vs 28.93%, p<0.001), and lipid vacuole (40.35% vs 8.26%, p<0.001) formation than PDM. Immunohistochemical analysis revealed a significant presence of CD20+ B lymphocytes in PDM and a higher prevalence of CD8+ T lymphocytes in GLM, indicating differing immune responses. Treatment outcomes varied, with PDM patients responding well to surgery and anti-mycobacterial therapy, while GLM patients showed favorable responses to steroid therapy. Conclusion: PDM is a specific entity with a similar clinical presentation but distinct histopathological features and immune profiles to GLM. Further research is needed to elucidate the pathogenesis and optimize therapeutic approaches for these breast inflammatory conditions.

2.
Chin J Cancer Res ; 36(2): 124-137, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38751436

RESUMO

Objective: Primary resistance to trastuzumab frequently occurs in human epidermal growth factor receptor 2 (HER2)-positive (+) breast cancer patients and remains a clinical challenge. Pyrotinib is a novel tyrosine kinase inhibitor that has shown efficacy in the treatment of HER2+ breast cancer. However, the efficacy of pyrotinib in HER2+ breast cancer with primary trastuzumab resistance is unknown. Methods: HER2+ breast cancer cells sensitive or primarily resistant to trastuzumab were treated with trastuzumab, pyrotinib, or the combination. Cell proliferation, migration, invasion, and HER2 downstream signal pathways were analyzed. The effects of pyrotinib plus trastuzumab and pertuzumab plus trastuzumab were compared in breast cancer cells in vitro and a xenograft mouse model with primary resistance to trastuzumab. Results: Pyrotinib had a therapeutic effect on trastuzumab-sensitive HER2+ breast cancer cells by inhibiting phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) and rat sarcoma virus (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase (MAPK)/extracellular-signal regulated kinase (ERK) pathways. In primary trastuzumab-resistant cells, pyrotinib inhibited cell growth, migration, invasion, and HER2 downstream pathways, whereas trastuzumab had no effects. The combination with trastuzumab did not show increased effects compared with pyrotinib alone. Compared with pertuzumab plus trastuzumab, pyrotinib plus trastuzumab was more effective in inhibiting cell proliferation and HER2 downstream pathways in breast cancer cells and tumor growth in a trastuzumab-resistant HER2+ breast cancer xenograft model. Conclusions: Pyrotinib-containing treatments exhibited anti-cancer effects in HER2+ breast cancer cells sensitive and with primary resistance to trastuzumab. Notably, pyrotinib plus trastuzumab was more effective than trastuzumab plus pertuzumab in inhibiting tumor growth and HER2 downstream pathways in HER2+ breast cancer with primary resistance to trastuzumab. These findings support clinical testing of the therapeutic efficacy of dual anti-HER2 treatment combining an intracellular small molecule with an extracellular antibody.

3.
Biochemistry ; 63(7): 880-892, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38501608

RESUMO

Ras-related nuclear protein (Ran) is a member of the Ras superfamily of small guanosine triphosphatases (GTPases) and a regulator of multiple cellular processes. In healthy cells, the GTP-bound form of Ran is concentrated at chromatin, creating a Ran•GTP gradient that provides the driving force for nucleocytoplasmic transport, mitotic spindle assembly, and nuclear envelope formation. The Ran•GTP gradient is maintained by the regulator of chromatin condensation 1 (RCC1), a guanine nucleotide exchange factor that accelerates GDP/GTP exchange in Ran. RCC1 interacts with nucleosomes, which are the fundamental repeating units of eukaryotic chromatin. Here, we present a cryo-EM analysis of a trimeric complex composed of the nucleosome core particle (NCP), RCC1, and Ran. While the contacts between RCC1 and Ran in the complex are preserved compared with a previously determined structure of RCC1-Ran, our study reveals that RCC1 and Ran interact dynamically with the NCP and undergo rocking motions on the nucleosome surface. Furthermore, the switch 1 region of Ran, which plays an important role in mediating conformational changes associated with the substitution of GDP and GTP nucleotides in Ras family members, appears to undergo disorder-order transitions and forms transient contacts with the C-terminal helix of histone H2B. Nucleotide exchange assays performed in the presence and absence of NCPs are not consistent with an active role for nucleosomes in nucleotide exchange, at least in vitro. Instead, the nucleosome stabilizes RCC1 and serves as a hub that concentrates RCC1 and Ran to promote efficient Ran•GDP to Ran•GTP conversion.


Assuntos
Cromatina , Nucleossomos , Proteína ran de Ligação ao GTP , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Microscopia Crioeletrônica , Guanosina Trifosfato/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Nucleossomos/química , Nucleossomos/metabolismo , Nucleotídeos/metabolismo , Proteína ran de Ligação ao GTP/metabolismo , Humanos , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo
4.
Chin Med J (Engl) ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38403898

RESUMO

BACKGROUND: Breast cancer (BC) risk-stratification tools for Asian women that are highly accurate and can provide improved interpretation ability are lacking. We aimed to develop risk-stratification models to predict long- and short-term BC risk among Chinese women and to simultaneously rank potential non-experimental risk factors. METHODS: The Breast Cancer Cohort Study in Chinese Women, a large ongoing prospective dynamic cohort study, includes 122,058 women aged 25-70 years from the eastern part of China. We developed multiple machine-learning risk prediction models using parametric models (penalized logistic regression, bootstrap, and ensemble learning), which were the short-term ensemble penalized logistic regression (EPLR) risk prediction model and the ensemble penalized long-term (EPLT) risk prediction model to estimate BC risk. The models were assessed based on calibration and discrimination, and following this assessment, they were externally validated in new study participants from 2017 to 2020. RESULTS: The AUC values of the short-term EPLR risk prediction model were 0.800 for the internal validation and 0.751 for the external validation set. For the long-term EPLT risk prediction model, the area under the receiver operating characteristic curve was 0.692 and 0.760 in internal and external validations, respectively. The net reclassification improvement index of the EPLT relative to the Gail and the Han Chinese Breast Cancer Prediction Model (HCBCP) models for external validation was 0.193 and 0.233, respectively, indicating that the EPLT model has higher classification accuracy. CONCLUSIONS: We developed the EPLR and EPLT models to screen populations with a high risk of developing BC. These can serve as useful tools to aid in risk-stratified screening and BC prevention.

5.
Mol Cell ; 84(3): 429-446.e17, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215753

RESUMO

Nucleosomes, the basic structural units of chromatin, hinder recruitment and activity of various DNA repair proteins, necessitating modifications that enhance DNA accessibility. Poly(ADP-ribosyl)ation (PARylation) of proteins near damage sites is an essential initiation step in several DNA-repair pathways; however, its effects on nucleosome structural dynamics and organization are unclear. Using NMR, cryoelectron microscopy (cryo-EM), and biochemical assays, we show that PARylation enhances motions of the histone H3 tail and DNA, leaving the configuration of the core intact while also stimulating nuclease digestion and ligation of nicked nucleosomal DNA by LIG3. PARylation disrupted interactions between nucleosomes, preventing self-association. Addition of LIG3 and XRCC1 to PARylated nucleosomes generated condensates that selectively partition DNA repair-associated proteins in a PAR- and phosphorylation-dependent manner in vitro. Our results establish that PARylation influences nucleosomes across different length scales, extending from the atom-level motions of histone tails to the mesoscale formation of condensates with selective compositions.


Assuntos
Nucleossomos , Poli ADP Ribosilação , Nucleossomos/genética , Poli ADP Ribosilação/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Microscopia Crioeletrônica , Condensados Biomoleculares , Reparo do DNA , Histonas/genética , Histonas/metabolismo , DNA/genética , DNA/metabolismo , Dano ao DNA , Poli(ADP-Ribose) Polimerase-1/metabolismo
6.
Genome Med ; 16(1): 11, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38217005

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NAC) has become a standard treatment strategy for breast cancer (BC). However, owing to the high heterogeneity of these tumors, it is unclear which patient population most likely benefit from NAC. Multi-omics offer an improved approach to uncovering genomic and transcriptomic changes before and after NAC in BC and to identifying molecular features associated with NAC sensitivity. METHODS: We performed whole-exome and RNA sequencing on 233 samples (including matched pre- and post-treatment tumors) from 50 BC patients with rigorously defined responses to NAC and analyzed changes in the multi-omics landscape. Molecular features associated with NAC response were identified and validated in a larger internal, and two external validation cohorts, as well as in vitro experiments. RESULTS: The most frequently altered genes were TP53, TTN, and MUC16 in both pre- and post-treatment tumors. In comparison with pre-treatment tumors, there was a significant decrease in C > A transversion mutations in post-treatment tumors (P = 0.020). NAC significantly decreased the mutation rate (P = 0.006) of the DNA repair pathway and gene expression levels (FDR = 0.007) in this pathway. NAC also significantly changed the expression level of immune checkpoint genes and the abundance of tumor-infiltrating immune and stroma cells, including B cells, activated dendritic cells, γδT cells, M2 macrophages and endothelial cells. Furthermore, there was a higher rate of C > T substitutions in NAC nonresponsive tumors than responsive ones, especially when the substitution site was flanked by C and G. Importantly, there was a unique amplified region at 8p11.23 (containing ADGRA2 and ADRB3) and a deleted region at 3p13 (harboring FOXP1) in NAC nonresponsive and responsive tumors, respectively. Particularly, the CDKAL1 missense variant P409L (p.Pro409Leu, c.1226C > T) decreased BC cell sensitivity to docetaxel, and ADGRA2 or ADRB3 gene amplifications were associated with worse NAC response and poor prognosis in BC patients. CONCLUSIONS: Our study has revealed genomic and transcriptomic landscape changes following NAC in BC, and identified novel biomarkers (CDKAL1P409L, ADGRA2 and ADRB3) underlying chemotherapy resistance and poor prognosis, which could guide the development of personalized treatments for BC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Perfilação da Expressão Gênica , Genômica , Proteínas Repressoras/genética , Fatores de Transcrição Forkhead/genética , Receptores Adrenérgicos beta 3/genética
7.
Int J Infect Dis ; 140: 25-30, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142735

RESUMO

OBJECTIVES: To assess the efficacy and safety of rifampicin-based triple therapy (rifampicin, isoniazid, and ethambutol) for treating NPM. METHODS: This single-center, single-arm, prospective clinical trial was conducted at the Second Hospital of Shandong University (Jinan, China). Patients with pathologically diagnosed granulomatous lobular mastitis and periductal mastitis received triple drugs, i.e., rifampicin (450 mg/day), isoniazid (300 mg/day), and ethambutol (15 mg/kg/day), until complete response or the investigator decided to discontinue treatment. The primary endpoint was the complete response rate (CRR) assessed by the investigator. The secondary endpoints included the overall remission rate (ORR), recurrence rate (RR), and safety. RESULTS: A total of 218 patients were enrolled in the study between January 1, 2013 and October 31, 2020. With a median follow-up time of 48 months, the CRR and the ORR were 78.44% and 94.04%, respectively. While 13 patients (5.96%) demonstrated no response and 19 relapsed (8.72%). Adverse events (AEs) were not common. The most common AEs during treatment were liver dysfunction (1.83%), gastrointestinal reactions (1.83%), fatigue (1.83%), erythema (1.38%), and menstrual disorders (0.92%). CONCLUSION: Rifampicin, isoniazid, and ethambutol demonstrated promising response rates with acceptable safety profiles in patients with NPM. Further confirmatory trial is warranted in the future. TRIAL REGISTRATION: The study was approved by the Ethics Committee of the Second Hospital of Shandong University and retrospectively registered at the China Clinical Trial Registration Center (registration number: ChiCTR2100049591).


Assuntos
Mastite , Rifampina , Feminino , Humanos , Etambutol/efeitos adversos , Isoniazida/efeitos adversos , Estudos Prospectivos , Rifampina/efeitos adversos
8.
Ann Med ; 55(1): 2224045, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37350731

RESUMO

BACKGROUND: Breast abscess is a common and intractable clinical condition and the use of needle aspiration (NA) or incision and drainage (ID) in treatment is controversial. This meta-analysis aimed to systematically compare the clinical effectiveness of NA and ID in treating breast abscesses. METHODS: The Web of Science, ScienceDirect, PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, and Wanfang Data were searched for randomized controlled trials (RCTs) published from inception to January 7, 2022. The ROB-2 tool assessed risk of bias; the GRADE methodology rated certainty in outcomes; and Stata 16.0 performed data analyses. RESULTS: Nine RCTs were included, including 703 patients. The results showed there was no significant difference in cure rate between the two groups (relative risk [RR] = 0.96, 95% confidence interval [CI] [0.86, 1.07]; p = .469), and after subgroup analysis, we found that it was not related to the use of ultrasound guidance or not. There was no significant difference in the recurrence rate (RR = 0.68, 95% CI [0.35, 1.30]; p = .241). Furthermore, the NA group was associated with shorter healing time (weighted mean differences = -11.02, 95% CI [-15.14, -6.90]; p < .001), lower incidence of breast fistula (RR = 0.21, 95% CI [0.06, 0.72]; p = .013), lower interrupted breastfeeding rate (RR = 0.28, 95% CI [0.20, 0.39]; p < .001), and higher satisfaction rate of appearance (RR = 1.51, 95% CI [1.03-2.21]; p = .035). CONCLUSION: NA has better advantages in terms of healing time, avoidance of breast fistula, continuous breastfeeding, and patient satisfaction. Although NA and ID have similar cure and recurrence rates, NA, with or without ultrasound guidance, could be used as a first-line treatment for breast abscesses. Patients with large volumes, multicompartmental abscesses, or those who have been ineffective against multiple NA, should be considered for ID.KEY MESSAGESBreast abscess is a common and intractable clinical condition in general surgery.Compared with ID for breast abscesses, NA has better advantages in terms of healing time, avoidance of breast fistula, continuous breastfeeding, and patient satisfaction and could be used as a first-line treatment for breast abscesses.Patients with large volumes, multicompartmental abscesses, or those who have been ineffective against multiple NA, should be considered for ID.


Assuntos
Abscesso , Fístula , Humanos , Abscesso/cirurgia , Drenagem/efeitos adversos , Drenagem/métodos , Resultado do Tratamento , Viés
9.
China CDC Wkly ; 5(15): 333-339, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37193083

RESUMO

What is already known about this topic?: Psychological and lifestyle factors are known to potentially play a significant role in the development of breast cancer. However, current evidence-based studies present controversial findings on the associations between depression, sleep duration, and breast cancer risk. What is added by this report?: This study investigated the potential risk factors of depressive symptoms and short sleep duration for breast cancer within the Breast Cancer Cohort Study in Chinese Women. The findings revealed that women experiencing depressive symptoms and short sleep duration exhibited a heightened risk of developing breast cancer, particularly among the older population. What are the implications for public health practice?: Public policy ought to prioritize early health education interventions targeting psychological factors in order to facilitate the prevention of breast cancer.

10.
Proc Natl Acad Sci U S A ; 120(15): e2301063120, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37011222

RESUMO

Epigenetic modifications of chromatin play a critical role in regulating the fidelity of the genetic code and in controlling the translation of genetic information into the protein components of the cell. One key posttranslational modification is acetylation of histone lysine residues. Molecular dynamics simulations, and to a smaller extent experiment, have established that lysine acetylation increases the dynamics of histone tails. However, a systematic, atomic resolution experimental investigation of how this epigenetic mark, focusing on one histone at a time, influences the structural dynamics of the nucleosome beyond the tails, and how this translates into accessibility of protein factors such as ligases and nucleases, has yet to be performed. Herein, using NMR spectroscopy of nucleosome core particles (NCPs), we evaluate the effects of acetylation of each histone on tail and core dynamics. We show that for histones H2B, H3, and H4, the histone core particle dynamics are little changed, even though the tails have increased amplitude motions. In contrast, significant increases to H2A dynamics are observed upon acetylation of this histone, with the docking domain and L1 loop particularly affected, correlating with increased susceptibility of NCPs to nuclease digestion and more robust ligation of nicked DNA. Dynamic light scattering experiments establish that acetylation decreases inter-NCP interactions in a histone-dependent manner and facilitates the development of a thermodynamic model for NCP stacking. Our data show that different acetylation patterns result in nuanced changes to NCP dynamics, modulating interactions with other protein factors, and ultimately controlling biological output.


Assuntos
Histonas , Nucleossomos , Histonas/metabolismo , Acetilação , Lisina/metabolismo , Processamento de Proteína Pós-Traducional
11.
Nat Struct Mol Biol ; 30(4): 502-511, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36997760

RESUMO

Heterotrimeric G proteins serve as membrane-associated signaling hubs, in concert with their cognate G-protein-coupled receptors. Fluorine nuclear magnetic resonance spectroscopy was employed to monitor the conformational equilibria of the human stimulatory G-protein α subunit (Gsα) alone, in the intact Gsαß1γ2 heterotrimer or in complex with membrane-embedded human adenosine A2A receptor (A2AR). The results reveal a concerted equilibrium that is strongly affected by nucleotide and interactions with the ßγ subunit, the lipid bilayer and A2AR. The α1 helix of Gsα exhibits significant intermediate timescale dynamics. The α4ß6 loop and α5 helix undergo membrane/receptor interactions and order-disorder transitions respectively, associated with G-protein activation. The αN helix adopts a key functional state that serves as an allosteric conduit between the ßγ subunit and receptor, while a significant fraction of the ensemble remains tethered to the membrane and receptor upon activation.


Assuntos
Subunidades alfa Gs de Proteínas de Ligação ao GTP , Proteínas Heterotriméricas de Ligação ao GTP , Humanos , Modelos Moleculares , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Conformação Proteica , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Subunidades alfa de Proteínas de Ligação ao GTP/química , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Ligação Proteica
12.
BMC Cancer ; 22(1): 1070, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253742

RESUMO

BACKGROUND: Breast cancer (BC) is one of the most prevalent cancers worldwide but its etiology remains unclear. Obesity is recognized as a risk factor for BC, and many obesity-related genes may be involved in its occurrence and development. Research assessing the complex genetic mechanisms of BC should not only consider the effect of a single gene on the disease, but also focus on the interaction between genes. This study sought to construct a gene interaction network to identify potential pathogenic BC genes. METHODS: The study included 953 BC patients and 963 control individuals. Chi-square analysis was used to assess the correlation between demographic characteristics and BC. The joint density-based non-parametric differential interaction network analysis and classification (JDINAC) was used to build a BC gene interaction network using single nucleotide polymorphisms (SNP). The odds ratio (OR) and 95% confidence interval (95% CI) of hub gene SNPs were evaluated using a logistic regression model. To assess reliability, the hub genes were quantified by edgeR program using BC RNA-seq data from The Cancer Genome Atlas (TCGA) and identical edges were verified by logistic regression using UK Biobank datasets. Go and KEGG enrichment analysis were used to explore the biological functions of interactive genes. RESULTS: Body mass index (BMI) and menopause are important risk factors for BC. After adjusting for potential confounding factors, the BC gene interaction network was identified using JDINAC. LEP, LEPR, XRCC6, and RETN were identified as hub genes and both hub genes and edges were verified. LEPR genetic polymorphisms (rs1137101 and rs4655555) were also significantly associated with BC. Enrichment analysis showed that the identified genes were mainly involved in energy regulation and fat-related signaling pathways. CONCLUSION: We explored the interaction network of genes derived from SNP data in BC progression. Gene interaction networks provide new insight into the underlying mechanisms of BC.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Aprendizado de Máquina , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes
13.
Cancer Biomark ; 35(2): 193-206, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093688

RESUMO

BACKGROUND: The clinicopathological significance of spatial tumor-infiltrating lymphocytes (TILs) subpopulations is not well studied due to lack of high-throughput scalable methodology for studies with large human sample sizes. OBJECTIVE: Establishing a cyclic fluorescent multiplex immunohistochemistry (mIHC/IF) method coupled with computer-assisted high-throughput quantitative analysis to evaluate associations of six TIL markers (CD3, CD8, CD20, CD56, FOXP3, and PD-L1) with clinicopathological factors of breast cancer. METHODS: Our 5-plex mIHC/IF staining was shown to be reliable and highly sensitive for labeling three biomarkers per tissue section. Through repetitive cycles of 5-plex mIHC/IF staining, more than 12 biomarkers could be detected per single tissue section. Using open-source software CellProfiler, the measurement pipelines were successfully developed for high-throughput multiplex evaluation of intratumoral and stromal TILs. RESULTS: In analyses of 188 breast cancer samples from the Nashville Breast Health Study, high-grade tumors showed significantly increased intratumoral CD3+CD8+ cytotoxic T lymphocyte density (P= 0.0008, false discovery rate (FDR) adjusted P= 0.0168) and intratumoral PD-L1 expression (P= 0.0061, FDR adjusted P= 0.0602) compared with low-grade tumors. CONCLUSIONS: The high- and low-grade breast cancers exhibit differential immune responses which may have clinical significance. The multiplexed imaging quantification strategies established in this study are reliable, cost-efficient and applicable in regular laboratory settings for high-throughput tissue biomarker studies, especially retrospective and population-based studies using archived paraffin tissues.


Assuntos
Antígeno B7-H1 , Neoplasias da Mama , Humanos , Feminino , Imuno-Histoquímica , Antígeno B7-H1/metabolismo , Neoplasias da Mama/patologia , Biomarcadores Tumorais/metabolismo , Estudos Retrospectivos , Parafina/metabolismo , Linfócitos do Interstício Tumoral , Fatores de Transcrição Forkhead/metabolismo , Prognóstico
14.
Am J Physiol Cell Physiol ; 322(4): C739-C753, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35235425

RESUMO

One-third of current pharmaceuticals target G protein-coupled receptors (GPCRs), the largest receptor superfamily in humans and mediators of diverse physiological processes. This review summarizes the recent progress in GPCR structural dynamics, focusing on class A receptors and insights derived from nuclear magnetic resonance (NMR) and other spectroscopic techniques. We describe the structural aspects of GPCR activation and the various pharmacological models that capture aspects of receptor signaling behavior. Spectroscopic studies revealed that receptors and their signaling complexes are dynamic allosteric systems that sample multiple functional states under basal conditions. The distribution of states within the conformational ensemble and the kinetics of transitions between states are regulated through the binding of ligands, allosteric modulators, and the membrane environment. This ensemble view of GPCRs provides a mechanistic framework for understanding many of the pharmacological phenomena associated with receptor signaling, such as basal activity, efficacy, and functional bias.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Ligantes , Espectroscopia de Ressonância Magnética , Conformação Proteica , Receptores Acoplados a Proteínas G/metabolismo
15.
Front Oncol ; 12: 809570, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223490

RESUMO

BACKGROUND: Leptin (LEP) plays a physiological role through its specific receptor (LEPR) and is involved in the occurrence and development of breast cancer. Our current study aimed at determining the influence of single-nucleotide polymorphisms (SNPs) in the genes coding for LEP and LEPR on breast cancer risk. METHODS: In the present study, 963 breast cancer cases and 953 controls were enrolled. Five SNPs of LEP and two of LEPR were chosen to evaluate the correlation of selected SNPs with breast cancer susceptibility among women in northern and eastern China. Analyses were further stratified by body mass index (BMI), waist-hip rate (WHR), estrogen receptor, and progesterone receptor status. The expression patterns of risk variant-associated genes were detected by expression quantitative trait locus (eQTL) analysis with eQTLGen and The Cancer Genome Atlas database. RESULTS: There were significant differences between breast cancer cases and control groups in the menopausal status and family history of breast cancer. Two SNPs (rs1137101 and rs4655555) of the LEPR gene decreased overall breast cancer risk, and other five SNPs showed no significant association with breast cancer risk. rs1137101 (GA vs. GG; adjusted OR = 0.719, 95% CI = 0.578-0.894, p = 0.003) and rs4655555 (TT vs. AA; adjusted OR = 0.574, 95% CI = 0.377-0.873, p = 0.009) significantly decreased breast cancer risk after Bonferroni correction for multiple testing. In subgroup analyses, the GA and GA + AA genotypes of LEPR rs1137101 associated with decreased breast cancer risk in the subgroup of BMI ≤ 24 kg/m2 or WHR ≥ 0.85 after Bonferroni correction. Furthermore, we found that the expressions of rs4655555-associated gene LEPR and leptin receptor overlapping transcript (LEPROT) were upregulated in breast cancer tumor tissues compared with adjacent normal tissues, and a higher expression of LEPR in tumor tissues was correlated with poor prognosis of breast cancer patients using The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) data. CONCLUSION: Our study demonstrated that the polymorphisms rs1137101 and rs4655555 located in the LEPR gene decreased breast cancer risk in Chinese females, which might be a research-worthy bio-diagnostic marker and applied for early prediction and risk assessment of breast cancer.

16.
Elife ; 112022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986091

RESUMO

Cholesterol is a major component of the cell membrane and commonly regulates membrane protein function. Here, we investigate how cholesterol modulates the conformational equilibria and signaling of the adenosine A2A receptor (A2AR) in reconstituted phospholipid nanodiscs. This model system conveniently excludes possible effects arising from cholesterol-induced phase separation or receptor oligomerization and focuses on the question of allostery. GTP hydrolysis assays show that cholesterol weakly enhances the basal signaling of A2AR while decreasing the agonist EC50. Fluorine nuclear magnetic resonance (19F NMR) spectroscopy shows that this enhancement arises from an increase in the receptor's active state population and a G-protein-bound precoupled state. 19F NMR of fluorinated cholesterol analogs reveals transient interactions with A2AR, indicating a lack of high-affinity binding or direct allosteric modulation. The combined results suggest that the observed allosteric effects are largely indirect and originate from cholesterol-mediated changes in membrane properties, as shown by membrane fluidity measurements and high-pressure NMR.


Assuntos
Regulação Alostérica/efeitos dos fármacos , Colesterol/metabolismo , Receptor A2A de Adenosina/química , Animais , Escherichia coli , Espectroscopia de Ressonância Magnética , Saccharomycetales , Células Sf9 , Spodoptera
17.
J Food Sci ; 87(1): 112-123, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34859430

RESUMO

The ability of white, red, and blue irradiation to maintain sensory quality, health-promoting compounds, and antioxidant capacity, and regulate glucosinolate metabolism-related gene expression in post-harvest baby mustard was studied. Irradiation with 80 µmol m-2 s-1 extended the shelf life of post-harvest baby mustard. Irradiation delayed the increase in weight loss and the decrease in sensory parameter scores and the levels of ascorbic acid, total phenolics, glucosinolate, and antioxidant capacity during storage of baby mustard. Irradiation induced the expression of glucosinolate biosynthesis genes and inhibited glucosinolate degradation gene expression. The glucosinolate content and glucosinolate metabolism-related gene expression in post-harvest baby mustard were higher under white and red light irradiation compared with blue light irradiation. These findings indicate that irradiation (80 µmol m-2 s-1 ), especially of white and red light, is an effective technique for maintaining the sensory and nutritional qualities in post-harvest baby mustard stored at 20°C. PRACTICAL APPLICATION: This study was to evaluate the effect of white, red, and blue irradiation on the sensory quality, health-promoting compounds, antioxidant capacity, and glucosinolate metabolism-related gene expression of baby mustard during post-harvest storage, providing an effective and sustainable post-harvest method to extend shelf life and maintain the post-harvest quality of baby mustard under ambient temperature storage. Irradiation (80 µmol m-2 s-1 ), especially of white and red light, is an effective technique for maintaining the sensory and nutritional qualities in post-harvest baby mustard stored at 20°C.


Assuntos
Antioxidantes , Mostardeira , Ácido Ascórbico , Glucosinolatos , Compostos Fitoquímicos
18.
Int J Cancer ; 150(4): 705-717, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34648659

RESUMO

Because of the high heterogeneity of breast cancer outcome, identification of novel prognostic biomarkers is critical to improve patient stratification and guide precise treatment. We examined the prognostic value of gamma-interferon-inducible lysosomal thiol reductase (GILT) expression in a training set of 416 breast cancer patients and a validation set of 210 patients, and performed functional studies to investigate the functions and underlying mechanisms of GILT on breast cancer prognosis. Our results indicated that high GILT expression in breast cancer cells was associated with improved disease-free survival (DFS; hazard ratio [HR] = 0.189, 95% confidence interval [CI]: 0.099-0.361) and breast cancer-specific survival (BCSS; HR = 0.187, 95% CI: 0.080-0.437) of breast cancer patients both in the training set and the external validation set (HR = 0.453, 95% CI: 0.235-0.873 for DFS, HR = 0.488, 95% CI: 0.245-0.970 for BCSS). In vitro and in vivo studies showed that GILT overexpression inhibited breast cancer cells proliferation, invasion, migration and tumor formation in nude mice and increased sensitivity of breast cancer cells to standard treatment. Proteomics analysis indicated that GILT inhibited reactive oxygen species (ROS) and autophagy activation in breast cancer cells, and GILT overexpression-mediated tumor growth was further enhanced in the presence of autophagy or ROS inhibitors. Our results demonstrate that GILT expression can be effectively used to predict the prognosis and guide treatment strategies of breast cancer patients.


Assuntos
Neoplasias da Mama/mortalidade , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autofagia/fisiologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Humanos , Pessoa de Meia-Idade , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/análise , Prognóstico , Espécies Reativas de Oxigênio/metabolismo
19.
Patient Educ Couns ; 105(7): 1818-1827, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34952749

RESUMO

OBJECTIVE: To summarize the awareness levels of breast cancer (BC) worldwide and investigate factors associated with BC awareness to determine differences in awareness between China and other countries. METHODS: This systematic review followed the PRISMA guidelines and included 92 articles up to July, 2021. We calculated percentages for BC awareness levels and conducted subgroup analysis and cumulative meta-analysis. RESULTS: A total 84% (95% confidence interval [95%CI]: 78-90%) of women knew about BC; however, only 51% (95%CI: 37-66%) and 40% (95%CI: 24-56%) of women were aware of BC symptoms and BC risk factors, respectively. The most commonly known BC symptom was breast lump (71%, 95%CI: 62-80%), and BC family history was the most well-known BC risk factor (61%, 95%CI: 54-69%). Subgroup analysis showed lower awareness levels among Chinese and Asian women than women from other countries. Cumulative meta-analysis showed no obvious progress in BC awareness levels over time. We investigated 15 awareness-related factors, the most frequent of which were education level (61.8%), occupation (29.4%), and age (26.5%). CONCLUSION: BC awareness levels remain low. Improving BC awareness is critical, especially in developing countries. PRACTICE IMPLICATIONS: Effective education programs are urgently needed to improve women's BC awareness.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico , China , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos
20.
Carcinogenesis ; 43(1): 12-20, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-34919666

RESUMO

We have previously identified a genetic variant, rs34331122 in the 22q11.21 locus, as being associated with breast cancer risk in a genome-wide association study. This novel variant is located in the intronic region of the T-box transcription factor 1 (TBX1) gene. Cis-expression quantitative trait loci analysis showed that expression of TBX1 was regulated by the rs34331122 variant. In the current study, we investigated biological functions and potential molecular mechanisms of TBX1 in breast cancer. We found that TBX1 expression was significantly higher in breast cancer tumor tissues than adjacent normal breast tissues and increased with tumor stage (P < 0.05). We further knocked-down TBX1 gene expression in three breast cancer cell lines, MDA-MB-231, MCF-7 and T47D, using small interfering RNAs and examined consequential changes on cell oncogenicity and gene expression. TBX1 knock-down significantly inhibited breast cancer cell proliferation, colony formation, migration and invasion. RNA sequencing and flow cytometry analysis revealed that TBX1 knock-down in breast cancer cells induced cell cycle arrest in the G1 phase through disrupting expression of genes involved in the cell cycle pathway. Furthermore, survival analysis using the online Kaplan-Meier Plotter suggested that higher TBX1 expression was associated with worse outcomes in breast cancer patients, especially for estrogen receptor-positive breast cancer, with HRs (95% CIs) for overall survival (OS) and distant metastasis free survival (DMFS) of 1.5 (1.05-2.15) and 1.55 (1.10-2.18), respectively. In conclusion, our results suggest that the TBX1 gene may act as a putative oncogene of breast cancer through regulating expressions of cell cycle-related genes.


Assuntos
Neoplasias da Mama/genética , Ciclo Celular/genética , Oncogenes/genética , Proteínas com Domínio T/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , RNA Interferente Pequeno/genética
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