BRAF V600E and Novel Somatic Mutations in Thyroid Cancer of Libyan Patients

Background: Thyroid cancer (TC) is a common endocrine malignancy that frequently harbours the oncogenic V600E BRAF mutation. This mutation has received considerable attention in recent years for its potential utility in the risk stratification and management of TC. This study aims to investigate BRAF mutational status in thyroid cancer of Libyan patients and their association with clinicopathological factors. Methods: 44 thyroid tissue samples were analysed for mutations in exon 15 of the BRAF gene by performing polymerase chain reaction and Sanger sequencing. The results of BRAF mutation screening were correlated to clinical and pathological characteristics of the studied thyroid cancer patients. Statistical analyses were performed using SPSS. Results: The BRAF exon 15 mutations were detected in 19 (43.2%) of the thyroid cancer cases. The V600E was the most frequent one found in 15/44 (34.1%) cases. We also detected 6 other variants in 7 patients (15.9%), the S616F, the W619R and the T599S. Three mutations were associated with V600E, the L584I, the D587Y and the synonymous L597L. None of these mutations were reported previously in thyroid cancers. No statistical association was found between BRAF mutations and clinicopathological factors except with papillary thyroid cancer type (p= 0,032). Conclusions: Novel BRAF mutations and V600E were frequently detected in thyroid cancer of Libyan patients; this suggests a potential role of these novel mutations in carcinogenesis and in anti-EGFR therapy resistance.     

BRAF Mutations in Iranian Patients with Papillary Thyroid Carcinoma

Background: Papillary thyroid cancer or papillary thyroid carcinoma (PTC) is the most common thyroidcancer. The fact that it occasionally occurs in women aged 30-40 years old suggests that genetic alterations areinvolved its genesis. Recently, activator mutations in BRAF gene have been relatively frequently discovered.Materials and Methods: In this study, we tested 63 DNA samples from PTC patients to identify the V600Emutation frequency in the Ahvaz population. DNA was isolated from formalin fixed paraffin-embedded (FFPE)PTC tumor tissues. Genotyping was performed by PCR-RFLP and confirmed by direct DNA sequencing of asubset of PCR products. PCR-RFLP data were reported as genotype frequencies and percentages. Results: Fortynine out of 63 patients (77.8%) had a mutated heterozygote form while 14 (22.2%) showed normal genotype butnone demonstrated a mutant homozygote genotype. The frequency of V600E mutation was significantly high inPTC patients. Conclusions: These findings support involvement of V600E mutations in PTC occurrence in Iran.Assessment of correlations between BRAF V600E mutations and papillary thyroid cancer progression needs tobe performed.     

甲状腺乳头状癌BRAF V600E基因突变 及相关蛋白的表达

背景与目的:BRAF V600E基因突变可作为甲状腺乳头状癌靶向治疗的靶点,因此检测患者BRAF基因状态对于能否应用靶向药物治疗具有重要意义.观察BRAF V600E基因突变及突变蛋白VE1在甲状腺乳头状癌中的表达情况,并分析其与甲状腺乳头状癌的临床病理特征及其预后的关系.方法:采用DNA测序法及免疫组织化学法分别检测108例甲状腺乳头状癌、54例甲状腺腺瘤和54例结节性甲状腺肿标本中BRAF基因突变及其相关蛋白VE1的表达.结果:108例甲状腺乳头状癌基因突变率为67.6%,VE1表达率为64.8%,与甲状腺良性病变相比差异有统计学意义(P<0.05),与临床病理参数间无相关性.结论:甲状腺乳头状癌BRAF V600E基因突变率和BRAF V600E蛋白表达水平增高,可以作为鉴别甲状腺良、恶性肿瘤的有效指标.免疫组织化学法检测甲状腺乳头状癌BRAF V600E蛋白的表达与其基因突变的一致性高,可间接有效地反映BRAF V600E基因突变的状态.BRAF V600E基因突变及突变蛋白的表达与甲状腺乳头状癌患者预后无关.     

Surgical Perspective of T1799A BRAF Mutation Diagnostic Value in Papillary Thyroid Carcinoma

Background: Throughout Indonesia, thyroid cancer is one of the ten commonest malignancies, with papillarythyroid carcinoma (PTC) in our hospital accounting for about 60% of all thyroid nodules. Although fine needleaspiration biopsy (FNAB) is the most reliable diagnostic tool, some nodules are diagnosed as indeterminate andsecond surgery is common for PTC. The aim of this study was to establish the diagnostic value and feasibility oftesting the BRAF T1799A mutation on FNA specimens for improving PTC diagnosis. Materials and Methods: Thisprospective study enrolled 95 patients with thyroid nodules and future surgery planned. Results of mutationalstatus were compared with surgical pathology diagnosis. Results: Of the 70 cases included in the final analysis,62.8% were PTC and the prevalence of BRAF mutation was 38.6%. The sensitivity, specificity, positive predictivevalue (PPV), and negative predictive value (NPV) for BRAF mutation analysis were 36%, 100%, 100% and48%, respectively. With other data findings, nodules with “onset less than 5 year” and “hard consistency” wereproven as diagnostic determinants for BRAF mutation with a probability of 62.5%. This mutation was alsoa significant risk factor for extra-capsular extension. Conclusions: Molecular analysis of the BRAF T1799Amutation in FNAB specimens has high specificity and positive predictive value for PTC. It could be used in theselective patients with clinical characteristics to facilitate PTC diagnosis and for guidance regarding extent ofthyroidectomy.     

The association of the BRAF(V600E) mutation with prognostic factors and poor clinical outcome in papillary thyroid cancer: a meta-analysis

BACKGROUND:

The effects of the BRAF^V600E mutation on prognostic factors and poor clinical outcomes in papillary thyroid cancer (PTC) have not been fully quantified. The authors performed comprehensive meta‐analysis to assess the strength of associations between these conditions and the BRAF^V600E mutation.

METHODS:

The authors identified the clinical studies that examined the association of the BRAF^V600E mutation in surgical specimens with clinicopathologic outcomes between January 2003 and October 2010 using the Medline database. One hundred thirty‐one relevant studies were hand‐searched. The authors selected 27 studies that included 5655 PTC patients. They calculated the pooled odds ratios (ORs) or risk ratios with 95% confidence intervals (CIs) for each study using a random effect model.

RESULTS:

The average prevalence rate of the BRAF^V600E mutation was 49.4%. In 26 studies, compared with the patients who had the wild‐type BRAF genes, the PTC patients with the BRAF^V600E mutation had increased ORs of an extrathyroidal invasion (OR, 2.14; 95% CI, 1.68‐2.73), a lymph node metastasis (OR, 1.54; 95% CI, 1.21‐1.97), and an advanced TNM stage (OR, 2.00; 95% CI, 1.61‐2.49). In 8 studies, patients with the mutation had 2.14‐fold increased risk of recurrent and persistent disease (95% CI, 1.67‐2.74). The associations were generally consistent across the different study populations.

CONCLUSIONS:

This meta‐analysis demonstrates that the BRAF^V600E mutation is closely related to the high‐risk clinicopathological factors and poorer outcome of PTC. The results obtained here suggest that the BRAF^V600E mutation should be considered as a poor prognostic marker in PTC and may lead to better management for individual patients. Cancer 2012;. © 2011 American Cancer Society.     

Frequencies of BRAF mutations in clinical Pathology of cutaneous melanoma: a meta-analysis

Objective To explore the frequencies of BRAF mutations and the relationship between BRAF mutations and clinicopathological features of CM. Methods We search relevant literatures and the meta-analysis were conducted by Revman5.0 software. Results 9 studies were involved of BRAF mutations and 1134 patients are included. BRAF mutations are 47.3% of CM;As for patients over 50 years old, the OR of BRAF mutations is 2.30, 95% CI 1.36~3.91; the OR of BRAF mutations for SSM is 2.11, 95% CI 1.64~ 2.71; the OR of BRAF mutations for lesions in the trunk is 2.35, 95% CI 1.71~3.21; the OR of BRAF mutations for invasion depth less than 1mm is1.56, 95%CI 1.08~2.25. Conclusion mutations are more frequent in patients over 50 years old, in SSM and in patients whose lesions in the truck and invasion depth less than 1mm .They have no relationship with sex.     

朗格汉斯细胞组织细胞增生症中 BRAF V600E 和 MAP2K1基因突变的分析及其临床意义

目的：探讨我国朗格汉斯细胞组织细胞增生症（Langerhans cell histiocytosis,LCH）中 BRAF V600E 和MAP2K1基因突变发生状况及其临床意义。方法：随机选取35例 LCH 组织标本,采用桑格测序法检测其中BRAF V600E 和 MAP2K1基因突变状况,免疫组化法检测 BRAF V600E 蛋白的表达。分析 BRAF V600E、MAP2K1基因突变与 LCH 临床基本资料（年龄、性别、单／多系统）的关系。结果：在35例 LCH 患者中,男女比例为1．7∶1,82．9％侵及骨组织,97．1％是单系统 LCH（single system LCH,SS －LCH）,2．9％是多系统 LCH （multi －system LCH,MS －LCH）。桑格测序法检测 BRAF V600E 基因突变率为17．1％,MAP2K1基因突变率为14．3％,MAP2K1与 BRAF V600E 基因突变有互异性;免疫组化法检测 BRAF V600E 阳性表达率为28．6％,涵盖了桑格测序法测得的突变病例。BRAF V600E 和 MAP2 K1基因突变更多出现在未成年组（35．7％和28．6％）,其中 BRAF V600E 突变在未成年人组与成人组间有显著性差异（P ＝0．028）;BRAF V600E 和MAP2K1基因突变对生存的影响无统计学差异（P ＞0．05）。结论：我国 LCH 患者大部分都是 SS －LCH,主要侵及的部位是骨组织,且预后良好,5年生存率为97．1％。桑格法所测的 BRAF V600E 和 MAP2K1基因突变率均低于西方报道,两者存在互异性,分别为17．1％和14．3％。所有 MAP2K1基因突变都是点突变,没有框内缺失突变,发现一个新的突变位点：c．112 G ＞A p．E38K;BRAF V600E 和 MAP2K1基因突变主要发生于未成年组中,提示各年龄层中 LCH 的发病机理可能不同,可能 RAS ／RAF ／MEK／ERK 通路在未成年人 LCH 中发挥更重要的作用;另外这两种突变对 LCH 的生存无影响。     

基于GEO数据库的EGFR或KRAS突变型非小细胞肺癌耐药基因表达谱分析

目的 通过对相关数据库数据分析,探究NSCLC中EGFR和KRAS突变与耐药基因表达的关系,以及对患者生存和预后的影响.方法 对NCBI中GEO数据库中的数据集数据进行表达量分析、生存分析和相关性分析.结果 ①研究分析表明,ABCC1、GSTP1、MGMT1和RRM1基因在NSCLC组织中存在明显的高表达(P<0.0001;P<0.0001;P=0.0014;P<0.0001);而ERCC1和TUBB3基因表达差异没有统计学意义(P=0.3922;P=0.4583).②在KM组中,TUBB3、ABCC1和XPA基因存在明显的高表达(P=0.0169;P=0.033;P=0.0165),而在EM组中只有ABCC1存在明显的高表达(P=0.0002).③在KM组中ABCC1和XPA的表达情况呈正相关(P=0.025,γ=0.4992);而它们与TUBB3的表达情况呈负相关(P=0.0075,γ=-0.5789;P=0.0012,γ=-0.6696).④ABCC1和TUBB3的高表达会导致肺癌患者的总生存率和无复发生存率明显降低.结论 在NSCLC中EGFR或KRAS基因的突变会导致部分相关耐药基因的差异表达,这些差异表达的基因之间存在相关性,而且对患者的生存及预后又具有重要影响.     

p16、p53、BRAF、Bcl-2在卵巢浆液性肿瘤组织中的表达及临床意义

目的:探讨卵巢浆液性肿瘤组织中p16、p53、BRAF、Bcl-2的表达及临床意义。方法:收集宁夏医科大学总医院病理科2017年至2018年确诊的卵巢浆液性肿瘤136例,其中浆液性囊腺瘤52例,交界性囊腺瘤22例,低级别浆液性癌18例,高级别浆液性癌44例;另收集卵巢良性肿瘤和卵巢癌手术切除标本各30例。分别采用免疫组织化学SP法检测p16、p53、BRAF、Bcl-2的表达,实时定量PCR法检测p16、p53在卵巢良恶性肿瘤组织中的表达。结果:卵巢浆液性囊腺瘤、交界性囊腺瘤、低/高级别浆液性癌组织中p16的阳性率分别为3.8%、45.5%、88.9%、81.8%,p53为0、9.1%、55.6%、45.5%,BRAF为46.2%、45.5%、22.2%、31.8%,Bcl-2为46.2%、45.5%、38.9%、47.7%。不同类型浆液性肿瘤组织中p16、p53表达均有显著性差异（P＜0.001）,但BRAF、Bcl-2表达未见明显差异。与卵巢良性肿瘤相比,p16在交界性肿瘤、卵巢癌中的阳性表达明显升高,差异有显著统计学意义（P＜0.012 5）;p53在卵巢癌中的阳性表达明显高于良性肿瘤（P＜0.001）;p16和p53的表达呈正相关（P＜0.05）。p53、Bcl-2与卵巢癌淋巴结转移有相关性（P＜0.001）,p16、p53、Bcl-2与盆腔侵犯有关（P＜0.05）,p53、BRAF、Bcl-2与CA125表达有不同程度相关性（P＜0.05）。p16、p53联合检测对卵巢癌诊断的敏感性和特异性为90.0%、76.7%。结论:p16、p53、BRAF、Bcl-2参与卵巢癌的发生发展,p16和p53基因突变可能在卵巢浆液性肿瘤的恶性进展中发挥作用,联合检测p16、p53对卵巢癌诊断有指示意义。     

Platinum rechallenge in patients with advanced NSCLC: A pooled analysis

Introduction

The sole agents pemetrexed (PEM), docetaxel and anti-EGFR agents are approved second-line therapies for non-small cell lung cancer (NSCLC) after failure with cisplatin-based doublets. The potential usefulness of platinum-based doublets as rechallenge for second-line chemotherapy has not yet been established.

Methods

Studies that enrolled NSCLC platinum pre-treated patients were identified using electronic databases (MEDLINE and EMBASE). Pemetrexed and taxanes (TAXs)-based platinum combinations were considered. A systematic review was conducted using Comprehensive Meta-Analysis (version 2.2.064) software to calculate the event rate of response and 95% confidence interval. Median weighted progression-free survival (PFS) and overall survival (OS) time for PEM and TAXs-based doublets were compared by two-sided Student's t test. We tested for significant heterogeneity by Cochran's chi-square test and I² index.

Results

Eleven studies published between 1999 and 2012 were included in this analysis with a total of 607 patients enrolled; 468 were treated with PEM-doublets and 139 with TAXs-doublets. The overall response rate was 27.5% with a higher response rate of 37.8% (range, 29.7–46.7%) for TAXs-based treatment vs. 22% (range, 13.4–34.1%) for PEM-based combinations; (p < 0.0001). Median PFS and OS were 3.9 and 8.7 months with weighted PFS of 3.9 vs. 5.3 months (p < 0.0001) and similar OS for PEM vs. TAXs-based doublets.

Conclusions

With the limitations of small and not randomised trials included, this pooled analysis shows that NSCLC patients who relapsed after a first-line platinum-based chemotherapy obtain a tumour response of 27% from a platinum rechallenge containing PEM or TAXs. Response rate and median PFS appear better with TAXs-than with PEM-doublets.     

Hypermethylation of the DNA mismatch repair gene hMLH1 and its association with lymph node metastasis and T1799A BRAF mutation in patients with papillary thyroid cancer

BACKGROUND: It remains to be investigated whether the aberrant methylation of DNA repair genes plays a pathogenic role in BRAF mutation-promoted tumorigenesis of papillary thyroid cancer (PTC). METHODS: In the current study, the promoter methylation status of 23 DNA repair genes in relation to clinicopathologic characteristics and BRAF mutation was examined in PTC tumors using methylation-specific polymerase chain reaction. RESULTS: Among the 38 PTC tumors examined, 3 of 23 DNA repair genes were hypermethylated, including the hMLH1 gene in 8 of 38 samples (21%), the PCNA gene in 5 of 38 samples (13%), and the OGG1 gene in 2 of 38 samples (5%). Methylation of these genes was also found in some thyroid cancer cell lines. Methylation of the hMLH1 gene in particular was found to be associated with lymph node metastasis of PTC (5 of 8 samples [63%] in the methylation group vs 3 of 30 samples [10%] in the nonmethylation group; P = .0049). Methylation of the hMLH1 gene was also found to be associated with the T1799A BRAF mutation in PTC (6 of 19 samples (32%) in the BRAF mutation-positive group vs 2 of 19 samples (11%) in the BRAF mutation-negative group; P = .042). CONCLUSIONS: The data from the current study suggest that, as shown previously in colon cancer, aberrant methylation of the hMLH1 gene may play a role in BRAF mutation-promoted thyroid tumorigenesis.     

microRNA-99a 在非小细胞肺癌中的表达及临床意义

目的:探讨microRNA-99a在非小细胞肺癌(NSCLC)患者与正常人血清中的表达情况并分析其表达与临床病理特征及预后的关系。方法:收集70例非小细胞肺癌患者和60例正常人血清总RNA采用RT-PCR方法检测microRNA-99a的相对表达量,并分析其与临床病理资料和预后的相关性。结果:与正常人比较,血清microRNA-99a在非小细胞肺癌患者血清中表达下调,其表达与非小细胞肺癌患者的淋巴结转移、分化程度和TNM分期有显著相关性(P<0.05),非小细胞肺癌血清中microRNA-99a低表达者生存时间明显低于高表达者（P<0.05)。结论:非小细胞肺癌患者血清中microRNA-99a的表达下调与病情进展具有一定的相关性,可能作为肺癌治疗的新靶点。