Adenoid cystic carcinoma(ACC) of the breast is a rare special subtype of breast cancer characterized by the presence of a dual cell population of luminal and basaloid cells arranged in specific growth patterns. Most b...Adenoid cystic carcinoma(ACC) of the breast is a rare special subtype of breast cancer characterized by the presence of a dual cell population of luminal and basaloid cells arranged in specific growth patterns. Most breast cancers with triple-negative, basal-like breast features(i.e., tumors that are devoid of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression, and express basal cell markers) are generally high-grade tumors with an aggressive clinical course. Conversely, while ACCs also display a triple-negative, basal-like phenotype, they are usually low-grade and exhibit an indolent clinical behavior. Many discoveries regarding the molecular and genetic features of the ACC, including a specific chromosomal translocation t(6;9) that results in a MYB-NFIB fusion gene, have been made in recent years. This comprehensive review provides our experience with ACC of the breast, as well as an overview of clinical, histopathological, and molecular genetic features.展开更多
Breast cancer has been shown to live in the tumor microenvironment, which consists of not only breast cancer cells themselves but also a significant amount of pathophysiologically altered surrounding stroma and cells....Breast cancer has been shown to live in the tumor microenvironment, which consists of not only breast cancer cells themselves but also a significant amount of pathophysiologically altered surrounding stroma and cells. Diverse components of the breast cancer microenvironment, such as suppressive immune cells, re-programmed fibroblast cells, altered extracellular matrix (ECM) and certain soluble factors, synergistically impede an effective anti-tumor response and promote breast cancer progression and metastasis. Among these components, stromal cells in the breast cancer microenvironment are characterized by molecular alterations and aberrant signaling pathways, whereas the ECM features biochemical and biomechanical changes. However, triple-negative breast cancer (TNBC), the most aggressive subtype of this disease that lacks effective therapies available for other subtypes, is considered to feature a unique microenvironment distinct from that of other subtypes, especially compared to Luminal A subtype. Because these changes are now considered to significantly impact breast cancer development and progression, these unique alterations may serve as promising prognostic factors of clinical outcome or potential therapeutic targets for the treatment of TNBC. In this review, we focus on the composition of the TNBC microenvironment, concomitant distinct biological alteration, specific interplay between various cell types and TNBC cells, and the prognostic implications of these findings.展开更多
目的观察基底细胞样乳腺癌(basal-like breast carcinoma,BLBCs)的形态学和免疫组织化学特征,并探讨其诊断标准。方法对45例BLBCs与15例腔A型乳腺癌进行形态学观察及免疫组化检测,使用一抗包括CK5/6、CK14、SMA、CD10、p63、CD117、EGFR...目的观察基底细胞样乳腺癌(basal-like breast carcinoma,BLBCs)的形态学和免疫组织化学特征,并探讨其诊断标准。方法对45例BLBCs与15例腔A型乳腺癌进行形态学观察及免疫组化检测,使用一抗包括CK5/6、CK14、SMA、CD10、p63、CD117、EGFR、Vim、cyclin E、SKP2、Ki-67等指标。结果BLBCs形态学特征主要有:推进性生长方式(P=0.000);肿瘤间质有不同程度的淋巴细胞浸润(P=0.000);地图样坏死(P=0.000);非典型髓样癌特征(P=0.015);泡状核样(P=0.017);核分裂象多见(P=0.000);BLBCs高度表达以下免疫指标:CK5/6(P=0.000)、Vim(P=0.000)、CD117(P=0.018)、cyclin E(P=0.000)、SKP2(P=0.007)。结论BLBCs是经基因表型证实的一种特殊亚型的乳腺浸润性癌,形态学特征结合免疫组化特点可替代性诊断BLBCs。展开更多
Ductal carcinoma in situ （DCIS） is a category of early stage, non-invasive breast tumor defined by the intraductal proliferation of malignant breast epithelial cells. DCIS is a heterogeneous disease composed of mult...Ductal carcinoma in situ （DCIS） is a category of early stage, non-invasive breast tumor defined by the intraductal proliferation of malignant breast epithelial cells. DCIS is a heterogeneous disease composed of multiple molecular subtypes including luminal, HER2 and basal-like types, which are characterized by immuno-histochemical analyses and gene expression profiling. Following surgical and radiation therapies, patients with luminal-type, estrogen receptor-positive DCIS breast tumors can benefit from adjuvant endocrine-based treatment. However, there are no available targeted therapies for patients with basal-like DCIS （BL-DCIS） tumors due to their frequent lack of endocrine receptors and HER2 amplification, rendering them potentially susceptible to recurrence. Moreover, multiple lines of evidence suggest that DCIS is a non-obligate precursor of invasive breast carcinoma. This raises the possibility that targeting precursor BL-DCIS is a promising strategy to prevent BL-DCIS patients from the development of invasive basal-like breast cancer. An accumulating body of evidence demonstrates the existence of cancer stem-like cells （CSCs） in BL-DCIS, which potentially determine the features of BL-DCIS and their ability to progress into invasive cancer. This review encompasses the current knowledge in regard to the characteristics of BL-DCIS, identifcation of CSCs, and their biological properties in BL-DCIS. We summarize recently discovered relevant molecular signaling alterations that promote the generation of CSCs in BL-DCIS and the progression of BL-DCIS to invasive breast cancer, as well as the infuence of the tissue microenvironment on CSCs and the invasive transition. Finally, we discuss the translational implic-ations of these fndings for the prognosis and prevention of BL-DCIS relapse and progression.展开更多
Basal-like breast cancer with a luminal progenitor gene expression profile is an aggressive subtype of breast cancer with a poorer prognosis compared with other subtypes.However,genes that specifically promote basal-l...Basal-like breast cancer with a luminal progenitor gene expression profile is an aggressive subtype of breast cancer with a poorer prognosis compared with other subtypes.However,genes that specifically promote basal-like breast cancer development remain largely unknown.Here,we report that a novel gene C1orf106 plays an important role in maintaining the feature of basal-like/luminal progenitors.C1orf106 is frequently amplified and overexpressed in basal-like breast cancer and is associated with a poor outcome in patients.In human TCGA database,C1orf106 expression was correlated with upregulation of ELF5 and downregulation of GATA3,two transcription factors that regulate mammary gland stem cell fate.Enhanced expression of C1orf106 promotes tumor progression and expression of basal-like/luminal progenitor marker ELF5;depletion of C1orf106 suppresses tumorigenesis and expression of basal-like/luminal progenitor marker GATA3.These findings suggest that C1orf106 maintains the basal-like/luminal progenitor character through balancing the expression of ELF5 and GATA3.Taken together,we demonstrated that C1orf106 is an important regulator for basal-like/luminal progenitors and targeting C1orf106 is of therapeutic value for breast cancer.展开更多
[目的]分析细胞分裂周期蛋白42(Cdc42)和支架蛋白1(IQGAP1)与基底细胞样型乳腺癌(basal-like breast cancer,BLBC)临床病理特征之间的关系及二者之间的相关性,探讨Cdc42和IQGAP1在BLBC发生、发展及侵袭转移中的作用。[方法 ]采用免疫组...[目的]分析细胞分裂周期蛋白42(Cdc42)和支架蛋白1(IQGAP1)与基底细胞样型乳腺癌(basal-like breast cancer,BLBC)临床病理特征之间的关系及二者之间的相关性,探讨Cdc42和IQGAP1在BLBC发生、发展及侵袭转移中的作用。[方法 ]采用免疫组化方法检测60例BLBC、45例非基底细胞样型乳腺癌(non-basal-like breast carcinoma,Non-BLBC)和35例癌旁正常乳腺组织中Cdc42和IQGAP1的表达。[结果]Cdc42在BLBC中的表达明显高于Non-BLBC和癌旁正常乳腺组织(P<0.0125),IQGAP1在BLBC和Non-BLBC中的表达明显高于癌旁正常乳腺组织(P<0.0125);BLBC中Cdc42的表达与淋巴结转移和TNM分期密切相关(P<0.05),IQGAP1的表达与肿瘤大小和淋巴结转移密切相关(P<0.05),并且两者在BLBC中的表达呈正相关关系(r=0.638,P<0.05)。[结论]Cdc42和IQGAP1可能是促进肿瘤的局部侵袭和远处转移的重要因素,在BLBC的发生发展中起着重要的作用。展开更多
目的探讨碳酸酐酶IX(carbonic anhydrase IX,CAIX)在基底细胞样型乳腺癌(basal-like breast carcinomas,BLBCs)中的表达,分析其与乳腺癌患者相关临床病理指标的关系。方法应用免疫组化SP法检测CAIX在45例BLBCs、25例非基底细胞样型乳腺...目的探讨碳酸酐酶IX(carbonic anhydrase IX,CAIX)在基底细胞样型乳腺癌(basal-like breast carcinomas,BLBCs)中的表达,分析其与乳腺癌患者相关临床病理指标的关系。方法应用免疫组化SP法检测CAIX在45例BLBCs、25例非基底细胞样型乳腺癌(non-basal-like breast carcinomas,non-BLBCs)和10例正常乳腺组织中的表达。结果免疫组化检测结果显示,CAIX在BLBCs组织中的阳性表达率明显高于non-BLBCs和正常乳腺组织(P<0.05);BLBCs组织中CAIX的表达与肿瘤直径(P=0.001)、pTNM分期(P=0.014)及淋巴结转移(P=0.006)均呈正相关(P<0.05)。结论 CAIX在BLBCs中高表达,提示其可能参与该型乳腺癌病程进展的重要分子;CAIX的表达与多项临床病理指标、尤其是淋巴结转移密切相关,提示其可作为预测BLBCs淋巴结转移及预后的指标。展开更多
High levels of tubulin expression have been described in a variety of human malignant tumors, and glu-tubulin, in which the C-terminal tyrosine of α-tubulin is removed by tubulin carboxypeptidase. Over-expression has...High levels of tubulin expression have been described in a variety of human malignant tumors, and glu-tubulin, in which the C-terminal tyrosine of α-tubulin is removed by tubulin carboxypeptidase. Over-expression has been reported in the malignant tumors of the mammary gland and correlated with poor prognosis immunohistochemically. Furthermore, Nielsen et al. proposed that the use of a panel of four markers (ER, HER 2, CK 5/6, and EGFR) could accurately identify basal-like phenotype carcinoma (BPC) with widely available standard pathologic tools. In our study, major prognostic factors such as patient age, tumor size, histological grade, axillary lymph node metastasis, vessel invasion, and local recurrence in BPC were not significantly different from non BP carcinoma (NBPC). However, the BPC group showed a higher ratio of distant metastasis than that of the NBPC group. In triple-negative carcinoma (TNC) cases, staining for glu-tubulin was observed in 46 cases (63.8%), which consisted of 42 of the 58 BPC patients (72.4%) and 4 of the 14 NBPC patients (28.6%). A significant association was found between the expression of glu-tubulin and BPC, but not NBPC. It seems that our findings also agree with the observation that BPC exhibits aggressive biological behavior and increases the content of glu-tubulin, which plays a greater role in migration and invasion.展开更多
The Triple Negative “Basal-like” breast cancer (TNBL) tumours have a high proliferative capacity and develop a resistance phenotype associated with metastases. However, the management of TNBL carcinomas is still not...The Triple Negative “Basal-like” breast cancer (TNBL) tumours have a high proliferative capacity and develop a resistance phenotype associated with metastases. However, the management of TNBL carcinomas is still not standardized. Among the promising trails, gold nanoparticles could be a relevant tool for the development of a targeted treatment for this breast cancer subtype in monotherapy, associated and/or conjugated with other drugs. In this work, we report the cytotoxicity impact of gold nanoparticles wrapped in Poly-Ethylene Glycol (PEG) on the TNBL HCC-1937 breast cancer cell line. PEG-coated gold nanoparticles (PEG-Au NPs) were synthesized by a two-step method using a reduction process followed by a post-functionalization called PEGylation. PEG-Au NPs were characterized using transmission electron microscopy and X-ray diffraction. The gold content of the samples was determined using atomic absorption spectrometer. The cytotoxicity tests were performed using Sulforhodamine B survival test and resazurin viability test. PEG-Au NPs impact analysis on HCC1937 TNBL cell line showed a clear toxic action of type dose dependent and at long term. These PEGylated gold nanoparticles present a promising tool for the development of tumor-specific radiosensitizing vectors, with or without the association of other treatment strategies.展开更多
Retinoic acid receptor responder 3(RARRES3)has been characterized as a tumor suppressor in multiple types of cancer.This study aimed to examine the expression profile of RARRES3 across the PAM50 subtypes of breast can...Retinoic acid receptor responder 3(RARRES3)has been characterized as a tumor suppressor in multiple types of cancer.This study aimed to examine the expression profile of RARRES3 across the PAM50 subtypes of breast cancer.The DNA methylation status of RARRES3 was checked in the basal-like subtype,and the underlying mechanisms of its dysregulation were explored.RNA-sequencing(seq)and methylation data from The Cancer Genome Atlas were used for in-silico analysis.Basal-like representative SUM149 and MDA-MB-468 cell lines were used for in vitro and in vivo studies.Compared to tumor-adjacent normal tissues,only the basal-like tumor tissues had significantly downregulated RARRES3 expression.The methylation level of four CpG sites in the promoter region showed a strong negative correlation with RARRES3 expression.The gene coding for DNA methyltransferase 3A(DNMT3A)had consistent positive correlations with the methylation of the CpG sites.Chromatin Immunoprecipitation-quantitative polymerase chain-reaction and bisulfite sequencing PCR showed that DNMT3A could bind to the promoter region of RARRES3 and promote methylation of the CpG sites within the region.DNMT3A knockdown significantly restored RARRES3 expression at the mRNA and protein level in the two cell lines.CCK-8,colony formation,and flow cytometric analysis showed that RARRES3 overexpression attenuated the growth-promoting effects of DNMT3A overexpression and also weakened the DNMT3A overexpression-induced activation of ERK1/2 and PI3K/AKT signaling.In summary,this study revealed that DNMT3A enhances promoter methylation of the RARRES3 gene and suppresses its transcription in basal-like breast cancer.The DNMT3A-RARRES3 signaling pathway might be a potential target for the treatment of this tumor subtype.展开更多
文摘Adenoid cystic carcinoma(ACC) of the breast is a rare special subtype of breast cancer characterized by the presence of a dual cell population of luminal and basaloid cells arranged in specific growth patterns. Most breast cancers with triple-negative, basal-like breast features(i.e., tumors that are devoid of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression, and express basal cell markers) are generally high-grade tumors with an aggressive clinical course. Conversely, while ACCs also display a triple-negative, basal-like phenotype, they are usually low-grade and exhibit an indolent clinical behavior. Many discoveries regarding the molecular and genetic features of the ACC, including a specific chromosomal translocation t(6;9) that results in a MYB-NFIB fusion gene, have been made in recent years. This comprehensive review provides our experience with ACC of the breast, as well as an overview of clinical, histopathological, and molecular genetic features.
文摘Breast cancer has been shown to live in the tumor microenvironment, which consists of not only breast cancer cells themselves but also a significant amount of pathophysiologically altered surrounding stroma and cells. Diverse components of the breast cancer microenvironment, such as suppressive immune cells, re-programmed fibroblast cells, altered extracellular matrix (ECM) and certain soluble factors, synergistically impede an effective anti-tumor response and promote breast cancer progression and metastasis. Among these components, stromal cells in the breast cancer microenvironment are characterized by molecular alterations and aberrant signaling pathways, whereas the ECM features biochemical and biomechanical changes. However, triple-negative breast cancer (TNBC), the most aggressive subtype of this disease that lacks effective therapies available for other subtypes, is considered to feature a unique microenvironment distinct from that of other subtypes, especially compared to Luminal A subtype. Because these changes are now considered to significantly impact breast cancer development and progression, these unique alterations may serve as promising prognostic factors of clinical outcome or potential therapeutic targets for the treatment of TNBC. In this review, we focus on the composition of the TNBC microenvironment, concomitant distinct biological alteration, specific interplay between various cell types and TNBC cells, and the prognostic implications of these findings.
文摘目的观察基底细胞样乳腺癌(basal-like breast carcinoma,BLBCs)的形态学和免疫组织化学特征,并探讨其诊断标准。方法对45例BLBCs与15例腔A型乳腺癌进行形态学观察及免疫组化检测,使用一抗包括CK5/6、CK14、SMA、CD10、p63、CD117、EGFR、Vim、cyclin E、SKP2、Ki-67等指标。结果BLBCs形态学特征主要有:推进性生长方式(P=0.000);肿瘤间质有不同程度的淋巴细胞浸润(P=0.000);地图样坏死(P=0.000);非典型髓样癌特征(P=0.015);泡状核样(P=0.017);核分裂象多见(P=0.000);BLBCs高度表达以下免疫指标:CK5/6(P=0.000)、Vim(P=0.000)、CD117(P=0.018)、cyclin E(P=0.000)、SKP2(P=0.007)。结论BLBCs是经基因表型证实的一种特殊亚型的乳腺浸润性癌,形态学特征结合免疫组化特点可替代性诊断BLBCs。
基金Supported by The National Cancer Institute(NCI)of National Institutes of Health(NIH)of the United States of America to Zhou Q,Nos.5R01CA157779-03 and 5R01CA163820-04
文摘Ductal carcinoma in situ （DCIS） is a category of early stage, non-invasive breast tumor defined by the intraductal proliferation of malignant breast epithelial cells. DCIS is a heterogeneous disease composed of multiple molecular subtypes including luminal, HER2 and basal-like types, which are characterized by immuno-histochemical analyses and gene expression profiling. Following surgical and radiation therapies, patients with luminal-type, estrogen receptor-positive DCIS breast tumors can benefit from adjuvant endocrine-based treatment. However, there are no available targeted therapies for patients with basal-like DCIS （BL-DCIS） tumors due to their frequent lack of endocrine receptors and HER2 amplification, rendering them potentially susceptible to recurrence. Moreover, multiple lines of evidence suggest that DCIS is a non-obligate precursor of invasive breast carcinoma. This raises the possibility that targeting precursor BL-DCIS is a promising strategy to prevent BL-DCIS patients from the development of invasive basal-like breast cancer. An accumulating body of evidence demonstrates the existence of cancer stem-like cells （CSCs） in BL-DCIS, which potentially determine the features of BL-DCIS and their ability to progress into invasive cancer. This review encompasses the current knowledge in regard to the characteristics of BL-DCIS, identifcation of CSCs, and their biological properties in BL-DCIS. We summarize recently discovered relevant molecular signaling alterations that promote the generation of CSCs in BL-DCIS and the progression of BL-DCIS to invasive breast cancer, as well as the infuence of the tissue microenvironment on CSCs and the invasive transition. Finally, we discuss the translational implic-ations of these fndings for the prognosis and prevention of BL-DCIS relapse and progression.
基金supported by the Ministry of Science and Technology of China (2016YFC1302103 and 2015CB553906)the National Natural Science Foundation of China (81230051, 81472734,31170711, 81321003, and 30830048)+3 种基金the Beijing Natural Science Foundation (7120002)the 111 Project of the Ministry of Education, Peking University (BMU2018JC004, BMU20120314, and BMU20130364)a Leading Academic Discipline Project of Beijing Education Bureau to H.Za grant from the National Natural Science Foundation of China (81773199) to J.Z
文摘Basal-like breast cancer with a luminal progenitor gene expression profile is an aggressive subtype of breast cancer with a poorer prognosis compared with other subtypes.However,genes that specifically promote basal-like breast cancer development remain largely unknown.Here,we report that a novel gene C1orf106 plays an important role in maintaining the feature of basal-like/luminal progenitors.C1orf106 is frequently amplified and overexpressed in basal-like breast cancer and is associated with a poor outcome in patients.In human TCGA database,C1orf106 expression was correlated with upregulation of ELF5 and downregulation of GATA3,two transcription factors that regulate mammary gland stem cell fate.Enhanced expression of C1orf106 promotes tumor progression and expression of basal-like/luminal progenitor marker ELF5;depletion of C1orf106 suppresses tumorigenesis and expression of basal-like/luminal progenitor marker GATA3.These findings suggest that C1orf106 maintains the basal-like/luminal progenitor character through balancing the expression of ELF5 and GATA3.Taken together,we demonstrated that C1orf106 is an important regulator for basal-like/luminal progenitors and targeting C1orf106 is of therapeutic value for breast cancer.
文摘[目的]分析细胞分裂周期蛋白42(Cdc42)和支架蛋白1(IQGAP1)与基底细胞样型乳腺癌(basal-like breast cancer,BLBC)临床病理特征之间的关系及二者之间的相关性,探讨Cdc42和IQGAP1在BLBC发生、发展及侵袭转移中的作用。[方法 ]采用免疫组化方法检测60例BLBC、45例非基底细胞样型乳腺癌(non-basal-like breast carcinoma,Non-BLBC)和35例癌旁正常乳腺组织中Cdc42和IQGAP1的表达。[结果]Cdc42在BLBC中的表达明显高于Non-BLBC和癌旁正常乳腺组织(P<0.0125),IQGAP1在BLBC和Non-BLBC中的表达明显高于癌旁正常乳腺组织(P<0.0125);BLBC中Cdc42的表达与淋巴结转移和TNM分期密切相关(P<0.05),IQGAP1的表达与肿瘤大小和淋巴结转移密切相关(P<0.05),并且两者在BLBC中的表达呈正相关关系(r=0.638,P<0.05)。[结论]Cdc42和IQGAP1可能是促进肿瘤的局部侵袭和远处转移的重要因素,在BLBC的发生发展中起着重要的作用。
文摘目的探讨碳酸酐酶IX(carbonic anhydrase IX,CAIX)在基底细胞样型乳腺癌(basal-like breast carcinomas,BLBCs)中的表达,分析其与乳腺癌患者相关临床病理指标的关系。方法应用免疫组化SP法检测CAIX在45例BLBCs、25例非基底细胞样型乳腺癌(non-basal-like breast carcinomas,non-BLBCs)和10例正常乳腺组织中的表达。结果免疫组化检测结果显示,CAIX在BLBCs组织中的阳性表达率明显高于non-BLBCs和正常乳腺组织(P<0.05);BLBCs组织中CAIX的表达与肿瘤直径(P=0.001)、pTNM分期(P=0.014)及淋巴结转移(P=0.006)均呈正相关(P<0.05)。结论 CAIX在BLBCs中高表达,提示其可能参与该型乳腺癌病程进展的重要分子;CAIX的表达与多项临床病理指标、尤其是淋巴结转移密切相关,提示其可作为预测BLBCs淋巴结转移及预后的指标。
文摘High levels of tubulin expression have been described in a variety of human malignant tumors, and glu-tubulin, in which the C-terminal tyrosine of α-tubulin is removed by tubulin carboxypeptidase. Over-expression has been reported in the malignant tumors of the mammary gland and correlated with poor prognosis immunohistochemically. Furthermore, Nielsen et al. proposed that the use of a panel of four markers (ER, HER 2, CK 5/6, and EGFR) could accurately identify basal-like phenotype carcinoma (BPC) with widely available standard pathologic tools. In our study, major prognostic factors such as patient age, tumor size, histological grade, axillary lymph node metastasis, vessel invasion, and local recurrence in BPC were not significantly different from non BP carcinoma (NBPC). However, the BPC group showed a higher ratio of distant metastasis than that of the NBPC group. In triple-negative carcinoma (TNC) cases, staining for glu-tubulin was observed in 46 cases (63.8%), which consisted of 42 of the 58 BPC patients (72.4%) and 4 of the 14 NBPC patients (28.6%). A significant association was found between the expression of glu-tubulin and BPC, but not NBPC. It seems that our findings also agree with the observation that BPC exhibits aggressive biological behavior and increases the content of glu-tubulin, which plays a greater role in migration and invasion.
文摘The Triple Negative “Basal-like” breast cancer (TNBL) tumours have a high proliferative capacity and develop a resistance phenotype associated with metastases. However, the management of TNBL carcinomas is still not standardized. Among the promising trails, gold nanoparticles could be a relevant tool for the development of a targeted treatment for this breast cancer subtype in monotherapy, associated and/or conjugated with other drugs. In this work, we report the cytotoxicity impact of gold nanoparticles wrapped in Poly-Ethylene Glycol (PEG) on the TNBL HCC-1937 breast cancer cell line. PEG-coated gold nanoparticles (PEG-Au NPs) were synthesized by a two-step method using a reduction process followed by a post-functionalization called PEGylation. PEG-Au NPs were characterized using transmission electron microscopy and X-ray diffraction. The gold content of the samples was determined using atomic absorption spectrometer. The cytotoxicity tests were performed using Sulforhodamine B survival test and resazurin viability test. PEG-Au NPs impact analysis on HCC1937 TNBL cell line showed a clear toxic action of type dose dependent and at long term. These PEGylated gold nanoparticles present a promising tool for the development of tumor-specific radiosensitizing vectors, with or without the association of other treatment strategies.
基金supported by the Science&Technology Department of Sichuan Province,China(2022YFS0314).
文摘Retinoic acid receptor responder 3(RARRES3)has been characterized as a tumor suppressor in multiple types of cancer.This study aimed to examine the expression profile of RARRES3 across the PAM50 subtypes of breast cancer.The DNA methylation status of RARRES3 was checked in the basal-like subtype,and the underlying mechanisms of its dysregulation were explored.RNA-sequencing(seq)and methylation data from The Cancer Genome Atlas were used for in-silico analysis.Basal-like representative SUM149 and MDA-MB-468 cell lines were used for in vitro and in vivo studies.Compared to tumor-adjacent normal tissues,only the basal-like tumor tissues had significantly downregulated RARRES3 expression.The methylation level of four CpG sites in the promoter region showed a strong negative correlation with RARRES3 expression.The gene coding for DNA methyltransferase 3A(DNMT3A)had consistent positive correlations with the methylation of the CpG sites.Chromatin Immunoprecipitation-quantitative polymerase chain-reaction and bisulfite sequencing PCR showed that DNMT3A could bind to the promoter region of RARRES3 and promote methylation of the CpG sites within the region.DNMT3A knockdown significantly restored RARRES3 expression at the mRNA and protein level in the two cell lines.CCK-8,colony formation,and flow cytometric analysis showed that RARRES3 overexpression attenuated the growth-promoting effects of DNMT3A overexpression and also weakened the DNMT3A overexpression-induced activation of ERK1/2 and PI3K/AKT signaling.In summary,this study revealed that DNMT3A enhances promoter methylation of the RARRES3 gene and suppresses its transcription in basal-like breast cancer.The DNMT3A-RARRES3 signaling pathway might be a potential target for the treatment of this tumor subtype.
