Upregulation of microRNA-7 contributes to inhibition of the growth and metastasis of osteosarcoma cells through the inhibition of IGF1R

We aim to uncover the methylation of microRNA-7 (miR-7) promoter in osteosarcoma (OS) and the inner mechanism of miR-7 on the progression of OS cells. Expression and methylation state of miR-7 in OS tissues and cells were detected. With the aim to unearth the ability of miR-7 in OS, the proliferation, cell cycle progression, apoptosis, invasion, migration of OS cells, and the tumor growth in nude mice were determined. Meanwhile, IGF1R expression was detected and the association between miR-7 and IGF1R was confirmed. The proliferating cell nuclear antigen (PCNA) expression was tested by immunohistochemical staining, and the lung metastasis was observed by H&E staining. miR-7 expression was decreased and methylation state of miR-7 was increased in OS tissues and cells. Upregulated miR-7 inhibited proliferation, cell cycle progression, invasion,and migration, while inducing apoptosis of OS cells and the tumor growth as well as PCNA expression in nude mice. Expression of IGF1R was downregulated in OS cells with overexpression of miR-7. Experiments verified the binding site between miR-7 and IGF1R. Our study demonstrates that abnormal methylation of miR-7 contributes to decreased miR-7 in OS. In addition, miR-7 represses the initiation and progression of OS cells through the inhibition of IGF1R.     

NF2基因甲基化及其mRNA表达与乳腺癌发病的关系

目的:探讨乳腺癌中NF2基因启动子甲基化状态及其mRNA水平与乳腺癌发病的关系.方法:应用甲基化特异性聚合酶链反应(MSP)和逆转录-聚合酶链反应(RT-PCR)技术,检测47例乳腺癌组织及相应的癌旁组织和15例乳腺良性病变组织,分析NF2基因的甲基化与某些临床参数及mRNA表达的关系.结果:NF2基因启动子区在乳腺癌、癌旁和乳腺良性病变组织中的甲基化频率分别为57.4%(27/47)、23.4%(23/47)和0%(0/15).且乳腺癌组明显高于其余两组(P＜0.05).NF2基因发生甲基化与发病年龄、组织分型、转移和组织分级无相关性.乳腺癌组NF2基因mRNA的相对表达量(0.16±0.11)明显低于相应的癌旁组(0.27±0.14)及乳腺良性病变组(0.64±0.17)(P＜0.05).NF2基因启动子区甲基化频率与其mRNA表达呈负相关(Spearman's r=-0.314,P＜0.05).结论:NF2基因发生甲基化与乳腺癌的发生密切相关,NF2mRNA表达与NF2基因启动子高甲基化呈负相关.     

Expression of the human cancer/testis antigen NY-SAR-35 is activated by CpG island hypomethylation

The novel cancer/testis antigen gene, NY-SAR-35, is expressed exclusively in normal testis and in various histological types of tumor. However, the NY-SAR-35 gene expression is observed to be aberrant in several cancer cell lines and tissues. The analysis of methylation status of the NY-SAR-35 gene promoter in various cancer cell lines showed that its expression was related to methylation of the promoter region. Treatment of human cancer cell lines with the demethylating agent 5-aza-2′-deoxycytidine activated the expression of the NY-SAR-35 gene. In addition, transfection experiments on various fragments of the CpG-rich gene promoter indicate that in vitro methylation of the NY-SAR-35 gene promoter results in the loss of promoter activity. The expression of NY-SAR-35 is therefore activated by hypomethylation of the CpG island in the gene promoter.     

Epigenetic inactivation of the metastasis suppressor RECK enhances invasion of human colon cancer cells

Down-regulation of RECK, an important metastasis suppressor gene, has been found in human colon cancer. However, the molecular mechanism for this down- regulation and its biological significance are still unclear. In the present study, we investigated whether down-regulation of RECK is caused by epigenetic inactivation via promoter methylation and tested the effect of DNA methyltransferase (DNMT) inhibitor on RECK expression and cell invasion. The mRNA and protein levels of RECK in colon tumor tissues and their normal counterparts were compared. We found that down-regulation of RECK was found in 48% of the twenty five tumors analyzed. MSP analysis demonstrated that methylation of RECK promoter was detected in 44% (11/25) of the tumor tissues and a strong correlation between down-regulation and promoter methylation was found (P = 0.028). Promoter methylation was also found in SW480 and SW620 human colon cancer cell lines. DNA methyltransferase (DNMT) inhibitor 5'-azacytidine reversed promoter methylation, restored RECK expression and suppressed invasion by these two cell lines. Restoration of RECK is critical for 5'-azacytidine-mediated suppression of cell invasion because inhibition of RECK by a specific antibody significantly attenuated the anti-invasive ability of 5'-azacytidine. Taken together, our results suggest that down-regulation of the metastasis suppressor RECK in colon cancer is associated with promoter methylation and that a DNMT inhibitor may restore RECK expression to inhibit cell invasion.     

胃癌组织中MEG3基因甲基化状态及其临床意义

目的：探讨胃癌中MEG3基因差异性甲基化区域甲基化水平及其与MEG3表达之间的关系,并分析其临床病理意义。方法：利用荧光定量PCR检测38例胃癌组织及其对应癌旁正常组织中MEG3的表达水平,并利用甲基化特异性PCR检测MEG3基因差异性甲基化区域的甲基化水平。结果：①胃癌组织中MEG3表达水平明显低于正常癌旁对照组织（P〈0.05）;②胃癌组织MEG3差异性甲基化区域的甲基化率（21/38,55.3%）显著高于正常对照组织（10/38,26.3%,P〈0.05）③胃癌组织MEG3差异性甲基化区域的甲基化率在性别、年龄、发病部位的差异无统计学意义（P〉0.05）;在肿瘤的大小,淋巴结转移,浸润深度上差异有统计学意义（P〈0.05）。结论：胃癌组织中MEG3呈低表达水平,其差异性甲基化区域的甲基化与肿瘤的大小,淋巴结转移,浸润深度有关。     

Paired box 5 is a frequently methylated lung cancer tumour suppressor gene interfering β‐catenin signalling and GADD45G expression

Recent studies suggest that paired box 5 (PAX5) is down‐regulated in multiple tumours through its promoter methylation. However, the role of PAX5 in non‐small cell lung cancer (NSCLC) pathogenesis remains unclear. The aim of this study is to examine PAX5 expression, its methylation status, biological functions and related molecular mechanism in NSCLC. We found that PAX5 was widely expressed in normal adult tissues but silenced or down‐regulated in 88% (7/8) of NSCLC cell lines. PAX5 expression level was significantly lower in NSCLC than that in adjacent non‐cancerous tissues (P = 0.0201). PAX5 down‐regulation was closely associated with its promoter hypermethylation status and PAX5 expression could be restored by demethylation treatment. Frequent PAX5 promoter methylation in primary tumours (70%) was correlated with lung tumour histological types (P = 0.006). Ectopic expression of PAX5 in silenced lung cancer cell lines (A549 and H1975) inhibited their colony formation and cell viability, arrested cell cycle at G2 phase and suppressed cell migration/invasion as well as tumorigenicity in nude mice. Restoration of PAX5 expression resulted in the down‐regulation of β‐catenin and up‐regulation of tissue inhibitors of metalloproteinase 2, GADD45G in lung tumour cells. In summary, PAX5 was found to be an epigenetically inactivated tumour suppressor that inhibits NSCLC cell proliferation and metastasis, through down‐regulating the β‐catenin pathway and up‐regulating GADD45G expression.     

S100A4在子宫内膜癌中的表达及其临床病理意义

目的:检测S100A4在子宫内膜癌中的表达并分析其与子宫内膜癌临床病理指标的相关性,为子宫内膜癌的临床诊断、治疗及与预后预测提供参考依据。方法:采用免疫组织化学技术检测比较70例子宫内膜癌和40例正常子宫内膜组织中S100A4的表达,并分析子宫内膜癌组织中S100A4的表达与患者临床病理指标和生存期的相关性。结果:70例子宫内膜癌组织中S100A4的阳性表达率为57.14%(40/70),40例正常子宫内膜组织中S100A4的阳性表达率为10%(4/40),显著低于子宫内膜癌组织(P0.05)。子宫内膜癌组织中S100A4的表达与患者的年龄和淋巴结转移无显著相关,但与肿块浸润子宫肌壁深度、分化程度、临床分期均呈显著相关(P0.05)。S100A4呈阳性表达的子宫内膜癌患者的生存率和生存期均较S100A4呈阴性表达病例显著降低或缩短(P=0.01)。结论:子宫内膜癌组织中S100A4呈异常高表达,与子宫内膜癌的发生发展和预后密切相关,可能作为子宫内膜癌诊断和预后预测的参考标志物。     

Plasma GBP2 promoter methylation is associated with advanced stages in breast cancer

Blood methylated cell-free DNA (cfDNA) as a minimally invasive cancer biomarker has great importance in cancer management. Guanylate binding protein 2 (GBP2) has been considered as a possible controlling factor in tumor development. GBP2 gene expression and its promoter methylation status in both plasma cfDNA and tumor tissues of ductal carcinoma breast cancer patients were analyzed using SYBR green comparative Real-Time RT-PCR and, Methyl-specific PCR techniques, respectively in order to find a possible cancer-related marker. The results revealed that GBP2 gene expression and promoter methylation were inversely associated. GBP2 was down-regulated in tumors with emphasis on triple negative status, nodal involvement and higher cancer stages (p<0.0001). GBP2 promoter methylation on both cfDNA and tumor tissues were positively correlated and was detected in about 88% of breast cancer patients mostly in (Lymph node positive) LN+ and higher stages. Data provided shreds of evidence that GBP2 promoter methylation in circulating DNA may be considered as a possible effective non-invasive molecular marker in poor prognostic breast cancer patients with the evidence of its relation to disease stage and lymph node metastasis. However further studies need to evaluate the involvement of GBP2 promoter methylation in progression-free survival or overall survival of the patients.     

Epigenetic Inactivation of EFEMP1 Is Associated with Tumor Suppressive Function in Endometrial Carcinoma

Objective

EFEMP1, the epidermal growth factor–containing fibulin-like extracellular matrix protein 1, functions as an oncogene or a tumor suppressor depending on the cancer types. In this study, we aim to determine whether EFEMP1 affects the tumorigenesis and progression of endometrial carcinoma.

Methods

The expression of EFEMP1 was investigated using immunohistochemistry in a panel of normal endometrium (n = 40), atypical hyperplasia (n = 10) and endometrial carcinoma tissues (n = 84). Methylation status of the EFEMP1 promoter was detected by methylation-specific PCR (MSP) and bisulphite genomic sequencing. Up- or down-regulation of EFEMP1 were achieved by stable or transient transfection with pCMV6/GFP/Neo-EFEMP1 or pGPU6/GFP/Neo-shEFEMP1 respectively. Effects of EFEMP1 on tumor proliferation, invasion and migration were evaluated by MTT, plate colony formation, Transwell and wound healing assay. The nude mouse tumor xenograft assay was used to investigate function of EFEMP1 in vivo.

Results

Compared with normal endometrium (32/40) and atypical hyperplasia (7/10), EFEMP1 expression was much lower in endometrial carcinoma tissues (16/84) (P<0.001 and P = 0.02). EFEMP1 promoter was hypermethylated in endometrial carcinoma tissues (67%) as compared to normal tissue (10%) and down-regulation of EFEMP1 was associated with promoter hypermethylation. Treatment with 5-aza-2′-deoxycytidine (5-aza-dC) and/or trichostatin A (TSA) altered EFEMP1 methylation status, and restored EFEMP1 expression. Moreover, EFEMP1 decreased secretion of MMPs and inhibited tumor cell proliferation, metastasis and invasion in vitro and suppressed tumorigenesis in nude mice. Besides, EFEMP1 increased expression of E-cadherin and suppressed expression of vimentin in endometrial carcinoma.

Conclusion

EFEMP1 is a new candidate tumor suppressor gene in endometrial carcinoma, and is frequently silenced by promoter hypermethylation. It could inhibit tumor growth and invasion both in vitro and in vivo. Our findings propose that targeting EFEMP1 might offer future clinical utility in endometrial carcinoma.     

Aberrant promoter methylation and reduced expression of p16 gene in esophageal squamous cell carcinoma from Kashmir valley: a high-risk area

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent cancer in Jammu and Kashmir region of India and has multi-factorial etiology involving dietary habits, genetic factors, and gene environmental interactions. Inactivation of the p16 gene expression by aberrant promoter methylation plays an important role in the progression of esophageal carcinoma. In the present investigation, we have studied the role of p16 promoter methylation in 69 histopathologically confirmed ESCC tissues and compared it with corresponding normal adjacent tissues for DNA methylation in the CpG island in the p16 promoter region by methylation-specific polymerase chain reaction (MSP) and p16 protein expression by immunoblotting. The results showed loss of p16 expression in 67% (46/69) of tumor tissues compared to only 3% in control tissues (2/69). Promoter methylation was observed in 52% (36/69) of tumor tissues and it gradually increased with the increasing severity of histological grades of the cancer (P = 0.0001). Loss of p16 expression with promoter methylation was observed in 26 of 36 cases (72%). Analysis of patients dietary habits revealed a strong association between promoter methylation and high consumption of hot salted tea (P < 0.05) which is a most favourite drink commonly consumed by Kashmiri people.     

Upregulation of lncRNA GAS5 inhibits the growth and metastasis of cervical cancer cells

This study aims to figure out the methylation of long non-coding RNA GAS5 promoter in cervical cancer and the mechanism of GAS5 on the progression of cervical cancer cells. The expression of GAS5 and methylation state of GAS5 in cervical cancer tissues and cells were determined. With the aim to to explore the ability of GAS5 in the proliferation, cell cycle progression, apoptosis, invasion, migration as well as the tumor growth, and metastasis in nude mice were determined. The expression of GAS5 was decreased and methylation state of GAS5 was elevated in cervical cancer. Overexpression of GAS5 inhibited proliferation, cell cycle progression, invasion, migration while inducing apoptosis of cervical cancer cells as well as suppressed tumor growth and metastasis in nude mice. Our study demonstrates that abnormal methylation of GAS5 contributes to poor expression of GAS5 in cervical cancer. In addition, upregulation of GAS5 inhibits the cervical cancer development.     

COVID-19 disease and malignant cancers: The impact for the furin gene expression in susceptibility to SARS-CoV-2

Furin is a proprotein convertase that activates different kinds of regulatory proteins, including SARS-CoV-2 spike protein which contains an additional furin-specific cleavage site. It is essential in predicting cancer patients'' susceptibility to SARS-CoV-2 and the disease outcomes due to varying furin expressions in tumor tissues. In this study, we analyzed furin''s expression, methylation, mutation rate, functional enrichment, survival rate and COVID-19 outcomes in normal and cancer tissues using online databases, and our IHC. As a result, furin presented with biased expression profiles in normal tissues, showing 12.25-fold higher than ACE2 in the lungs. The furin expression in tumors were significantly increased in ESCA and TGCT, and decreased in DLBC and THYM, indicating furin may play critical mechanistic functions in COVID-19 viral entry into cells in these cancer patients. Line with furin over/downexpression, furin promoter hypo-/hyper-methylation may be the regulatory cause of disease and lead to pathogenesis of ESCA and THYM. Furthermore, presence of FURIN-201 isoform with functional domains (P_proprotein, Peptidase_S8 and S8_pro-domain) is highest in all cancer types in comparison to other isoforms, demonstrating its use in tumorigenesis and SARS-Cov-2 entry into tumor tissues. Furin mutation frequency was highest in UCES, and its mutation might elevate ACE2 expression in LUAD and UCEC, reduce ACE2 expression in COAD, elevate HSPA5 expression in PAAD, and elevate TMPRSS2 expression in BRCA. These results showed that furin mutations mostly increased expression of ACE2, HSPA5, and TMPRSS2 in certain cancers, indicating furin mutations might facilitate COVID-19 cell entry in cancer patients. In addition, high expression of furin was significantly inversely correlated with long overall survival (OS) in LGG and correlated with long OS in COAD and KIRC, indicating that it could be used as a favorable prognostic marker for cancer patients'' survival. GO and KEGG demonstrated that furin was mostly enriched in genes for metabolic and biosynthetic processes, retinal dehydrogenase activity, tRNA methyltransferase activity, and genes involving COVID-19, further supporting its role in COVID-19 and cancer metabolism. Moreover, Cordycepin (CD) inhibited furin expression in a dosage dependent manner. Altogether, furin''s high expression might not only implies increased susceptibility to SARS-CoV-2 and higher severity of COVID-19 symptoms in cancer patients, but also it highlights the need for cancer treatment and therapy during the COVID-19 pandemic. CD might have a potential to develop an anti-SARS-CoV-2 drug through inhibiting furin expression.     

ARHI和P130 在子宫内膜癌中的表达和意义

目的：探讨ARHI和P130 蛋白在子宫内膜癌中的表达状况,同时分析两因子在子宫内膜癌中的关联性。方法：收集80 例子 宫内膜癌,子宫内膜非典型增生型80 例及同时期因子宫肌瘤切除的40 例正常的子宫内膜的详细病例及高质量切片,设计分组 并使用免疫组化S-P法检测ARHI 蛋白和pRb2/P130的表达状况,并探究此两因子与子宫内膜癌的关联性。结果：ARHI蛋白阳 性表达率在正常子宫内膜组（97.50%）,子宫内膜非典型增生型组（53.75%）和子宫内膜癌组中（38.75%）三组中依次递减,组间差 异有统计学意义,P<0.05。ARHI蛋白阳性表达降低或缺失与子宫内膜癌的的恶性程度,手术病理分期有关(P<0.05),与子宫内膜 癌的类型无关（P>0.05）。Rb2/p130 蛋白的阳性表达率在三组中逐渐降低,在正常子宫内膜组（100%）,子宫内膜非典型增生型组 （56.25 %）及子宫内膜癌组（36.25 %）,组间差异有统计学意义,P<0.05。Rb2/P130 的阳性表达率降低或缺失与子宫内膜癌的组织 恶性程度,手术病理级别和组织学类型有关(P<0.05),同时Spearman 等级相关性分析表明：ARHI蛋白和Rb2/p130 蛋白表达在子 宫内膜癌中为正相关,r=0.435。结论：ARHI蛋白和Rb2/p130 的阳性表达率降低或缺失可能在某种程度上导致子宫内膜癌的产生 和恶化。     

High expression of ALDH1A3 might independently influence poor progression‐free and overall survival in patients with glioma via maintaining glucose uptake and lactate production

Recent studies have found that the acetaldehyde dehydrogenase 1A3 (ALDH1A3) gene is a marker of glioma stem cells. A total of 115 brain glioma specimens were collected and classified into grade I–IV, while non‐tumor brain tissue specimens, taken from 12 patients of vascular malformation surgery, were used as control. ALDH1A3 gene promoter methylation in glioma tissues was detected by pyrosequencing, while immunohistochemistry and western blot were used to detect ALDH1A3 protein expressions in different grades of glioma tissues and normal brain tissues. The expression of ALDH1A3 in the glioma cell line U87 was detected by quantitative real‐time polymerase chain reaction and RNA‐Seq technology was applied to investigate differentially expressed genes before and after silencing the ALDH1A3 gene. Among the 115 glioma tissue specimens, 50 (43.48%) showed low and 65 (56.52%) high expression of ALDH1A3, but no expression was detected in the control. Univariate and multivariate COX regression analyses showed that the patient's tumor pathological grade, the methylation status of ALDH1A3 promoter, and the expression of ALDH1A3 protein were risk factors for progression‐free survival (PFS) and overall survival (OS) (all P < 0.05) and the OS of mice with silenced ALDH1A3 in a glioma nude mouse model was prolonged. U87 experiments revealed that ALDH1A3 expression had significant effects on apoptosis, proliferation, cell cycle, mitochondrial membrane potential, glucose consumption, lactate production, invasion ability, and expression of the pyruvate kinase M2 (PKM2) and hexokinase 2 (HK2) in glioma cells. ALDH1A3 protein expression is a marker for poor PFS and OS in glioma patients.     

子宫内膜癌组织中uPA及Cath-D的表达及意义(英文)

目的:检测子宫内膜癌组织中尿激酶型纤溶酶原激活物(uPA)及组织蛋白酶(Cath-D)的表达并探讨相关性及其临床意义。方法:采用免疫组织化学方法(PV-6000二步法)检测31例子宫内膜癌组织(内膜癌组),17例子宫内膜增生组织(增生组)及10例正常子宫内膜组织(对照组)中uPA及Cath-D的表达,并研究其相关性。结果:1.内膜癌组中uPA和Cath-D的表达均高于增生组及对照组中的表达,差异均有统计学意义(P0.05);在增生组中的表达与对照组差异无统计学意义(P0.05)。2.uPA和Cath-D的阳性表达与子宫内膜癌的临床病理分期、组织学分级及肌层浸润深度有关,差异均具有统计学意义(P0.05)。3.内膜癌组中uPA与Cath-D的表达呈正相关(r=0.673,P0.05)。结论:uPA和Cath-D在子宫内膜癌发生发展及侵袭转移过程中起着协同作用,Cath-D可诱导产生活化的uPA,促进癌细胞的浸润转移,因此,两者的联合检测可有助于成为判断子宫内膜癌的发展及预后的重要指标。     

Epigenetic regulation of DACH1, a novel Wnt signaling component in colorectal cancer

Colorectal cancer (CRC) is one of the common malignant tumors worldwide. Both genetic and epigenetic changes are regarded as important factors of colorectal carcinogenesis. Loss of DACH1 expression was found in breast, prostate, and endometrial cancer. To analyze the regulation and function of DACH1 in CRC, 5 colorectal cancer cell lines, 8 cases of normal mucosa, 15 cases of polyps and 100 cases of primary CRC were employed in this study. In CRC cell lines, loss of DACH1 expression was correlated with promoter region hypermethylation, and re-expression of DACH1 was induced by 5-Aza-2'-deoxyazacytidine treatment. We found that DACH1 was frequently methylated in primary CRC and this methylation was associated with reduction in DACH1 expression. These results suggest that DACH1 expression is regulated by promoter region hypermethylation in CRC. DACH1 methylation was associated with late tumor stage, poor differentiation, and lymph node metastasis. Re-expression of DACH1 reduced TCF/LEF luciferase reporter activity and inhibited the expression of Wnt signaling downstream targets (c-Myc and cyclinD1). In xenografts of HCT116 cells in which DACH1 was re-expressed, tumor size was smaller than in controls. In addition, restoration of DACH1 expression induced G2/M phase arrest and sensitized HCT116 cells to docetaxel. DACH1 suppresses CRC growth by inhibiting Wnt signaling both in vitro and in vivo. Silencing of DACH1 expression caused resistance of CRC cells to docetaxel. In conclusion, DACH1 is frequently methylated in human CRC and methylation of DACH1 may serve as detective and prognostic marker in CRC.