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61.
62.
《Immunobiology》2020,225(2):151900
BackgroundNK cells as a part of innate immune system, are controlled by a set of activating and inhibitory KIR receptors (aKIR, iKIR) which are implicated in tumor microenvironment immunity through a variety of activating and inhibitory immune signals. KIRs are multi gene family receptors that differ in the number and type of genes among individuals. In the current research we determined the KIRs genes and genotypes impact on predisposition to meningioma development in Iranians.MethodsSequence-specific primers-polymerase chain reaction (SSP-PCR) was performed for genotyping of 16 KIRs in 159 meningioma cases and 362 age and sex matched healthy controls (CNs) at Shiraz Institute for Cancer Research.ResultsComparison of the KIR genotypes frequencies between cases and controls disclosed a highly significant increase in Bx genotype, CxTx subset and Cen AB and Tel AB in meningioma cases and a decrease in AA genotype, C4Tx subset and Cen AA, Tel AA, Tel BB in healthy controls.Among all 16 KIR genes, the carriers of KIR2DL5 and KIR2DS5 constituted a much greater proportion in meningioma than control group. Comparison of carrier frequencies of KIR2DS4 variants between case and controls revealed a higher frequency of KIR2DS4 full length (KIR2DS4fl) in meningioma cases and a lower frequency of KIR2DS4 deleted variant (KIR2DS4del) in controls. Furthermore, the simultaneous presence of 2DS5, 2DS4fl, CenAB, TelAB and absence of 2DS4del, CenAA, TelAA, TelBB, magnify the risk of developing meningioma substantially (OR ≈ 23). Altogether, 41 distinct KIR genotypes were characterized in 521 subjects. Among them, some individuals were characterized by seven peculiar genotypes that the linkage disequilibrium between KIR2DS2-KIR2DL2 and KIR2DL5-KIR2DS3-KIR2DS5 has not been detected. The carriers of certain genotypes with presence of as KIR2DL5 and absence of KIR2DS3, KIR2DS5 constituted a much higher proportion in meningioma than control group which increase the risk of meningioma up to 72 times.ConclusionThis case- control study suggests carriers of Bx genotype, KIR2DL5, KIR2DS5, 2DS4fl, ≥ 4 iKIR, CxTx subset as well as Cen AB and Tel AB are associated with an increased risk of developing meningioma whereas carrying KIR2DS4del, AA, C4TX genotypes and Cen AA, Tel AA, Tel BB reduce the genetic predisposition for meningioma. 相似文献
63.
《European journal of medical genetics》2020,63(3):103753
Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome (LS), is a common cancer-predisposing syndrome. This study aimed to investigate the spectrum of germ-line mutations in Russian LS patients. LS-related mismatch repair (MMR) genes were analyzed in 16 patients, who were forwarded to genetic testing due to strong clinical features of LS and had high-level microsatellite instability (MSI-H) in the tumor (n = 14) or unknown MSI status (n = 2). In addition, 672 consecutive colorectal cancer (CRC) cases were screened for family history; 15 patients were younger than 50 years and reported 2 or more instances of LS-related cancers in 1st- or 2nd-degree relatives. Seven of these cases demonstrated MSI-H and therefore were subjected to DNA germ-line testing. Overall, 17/23 (74%) subjects carried LS-associated gene variants (MLH1: 10; MSH2: 4; MSH6: 2; PMS2: 1), with 2 alleles (MLH1 c.677G > T and MSH2 с.1906G > C) detected twice. Testing for recurrent mutations of 30 consecutive MSI-H CRCs led to the identification of 2 additional subjects with LS. The analysis of all relevant publications identified 28 unrelated LS patients presented in Russian medical literature and 3 unrelated Russian LS subjects described in international journals. Overall, 15/49 (31%) genetic defects revealed in Russian LS patients were represented by six recurrent alleles (MLH1: c.350C > T, c.677G > T, c.1852_1854del; MSH2: c.942+3A > T, c.1861C > T, с.1906G > C). We conclude that the founder effect for LS in Russia is seemingly less pronounced than the one for hereditary breast-ovarian cancer syndrome, however testing for recurrent LS mutations may be considered feasible in some circumstances. 相似文献
64.
Hong Yan Liu Sheng Li Zhou Jian Wei Ku Dong Yun Zhang Bei Li Xue Na Han Zong Min Fan Ji Li Cui Hong Li Lin Er Tao Guo Xi Chen Yuan Yuan Jing Jing Han Wei Zhang Lian Qun Zhang Fu You Zhou Shi Xiu Liao Jun Yan Hong Li Dong Wang 《Archives of virology》2014,159(6):1393-1401
The etiological role of human papillomavirus (HPV) in cervical cancer has been well established. However, it is inconclusive whether HPV plays the same role in esophageal carcinogenesis. In this study, we detected HPV infection in 145 frozen esophageal tissues, including 30 normal epithelium (ENOR), 37 dysplasia (DYS) and 78 invasive squamous cell carcinoma (ESCC), and in 143 frozen cervical tissues composed of 30 normal epithelium (CNOR), 38 intraepithelial neoplasia (CIN) and 75 invasive squamous cell carcinoma (CSCC). The patients and symptom-free subjects enrolled in this study were from a high-incidence area for both ESCC and CSCC, Linzhou City, Northern China, from 2007 to 2009. The HPV infection analysis was conducted by using an HPV GenoArray Test Kit. We found that the high-risk HPV types accounted for more than 90 % of the HPV-positive lesions of esophagus and cervix tissues. The prevalence of high-risk HPV types increased significantly during the progression of both esophageal and cervical carcinogenesis (positive rate in esophageal tissues: 33 % ENOR, 70 % in DYS and 69 % in ESCC; positive rate in cervical tissues: 27 % in CNOR, 82 % in CIN and 88 % in CSCC; P < 0.001, respectively). Infection with the high-risk HPV types increased the risk for both DYS and ESCC by 4-fold (DYS vs. ENOR: OR = 4.73, 95 %CI = 1.68-13.32; ESCC vs. ENOR: OR = 4.50, 95 %CI = 1.83-11.05) and increased the risk for both CIN and CSCC by 12-fold and 20-fold (CIN vs. CNOR: OR = 12.18, 95 %CI = 3.85-38.55; CSCC vs. CNOR: OR = 20.17, 95 %CI = 6.93-58.65), respectively. The prevalence of high-risk types in ESCC patients was lower than that in CSCC patients (P = 0.005) and was significantly associated with the degree of ESCC tumor infiltration (P = 0.001). HPV 16 was the most prevalent subtype in both esophageal and cervical tissues. Single HPV infection increased significantly along with the progression of ESCC and maintained a high level in cervical tissues, regardless of whether they were CNOR or CSCC tissues. Our results showed that infection with HPV, especially the high-risk types, was positively associated with both esophageal and cervical cancers, suggesting that HPV also plays a role in the etiology of ESCC in the high-incidence area. 相似文献
65.
Bin Qiao Baoxia He Jinghua Cai Wenli Yang 《International journal of clinical and experimental pathology》2014,7(1):28-37
This study is to detect the co-expression of embryonic stem cell-related markers (Oct4 and Sox2) in the carcinogenesis of oral mucosa. The expression profile of these markers was studied by immunohistochemistry assay in rat and human samples. The normal oral mucosa (20 cases) and the transforming oral mucosa (20 cases) were performed in rat samples. The precancerous lesions (20 cases), OSCCs in primary site (116 cases), corresponding epithelial non-cancer tissues adjacent to the OSCC (20 cases) and 46 paired metastatic OSCCs in lymph nodes were performed in human samples. The co-expression of the two markers was defined as both of them are positively detected in the same site of one case under one selected field of microscope. The results indicated that Oct4 and Sox2 were individually detected in normal oral mucosa, but they cannot be co-expressed in the same site of one case. The co-expression of Oct4 and Sox2 (Oct4+Sox2+) was frequently detected in the transforming oral mucosa of rat (16/20), precancerous lesions of human (12/20) and epithelial non-cancer tissues adjacent to the OSCC (18/20). Also, Oct4+Sox2+ profile was remarkable noted in the primary sites of OSCCs (38/116). In the 46 paired OSCCs (primary sites with lymph node metastasis), Oct4+Sox2+ profile (8/46) was less frequently detected than Oct4low/-Sox2low/- (14/46) profile in the metastatic sites. To conclude, this study suggests Oct4 and Sox2 are expressed in normal oral mucosa, premalignant diseases, primary sites of OSCCs and metastasis sites of OSCCs. Oct4+Sox2+ profile may contribute to the malignant transformation of oral mucosa. 相似文献
66.
F. Vajda 《Journal of clinical neuroscience》2012,19(11):1475-1477
Antiepileptic drug (AED) therapy is complex, with numerous traditional drugs and more than 10 second-generation drugs being approved since the mid-1990s. The burden of epilepsy is compounded by the adverse effects of these drugs, which comprise a variety of manifestations, the most devastating of which is their association with physical and cognitive foetal malformations in babies exposed to these agents in utero. Many effects are dose-related – a clear understanding of these adverse effects is desirable to be able to adjust medications and medication regimens to suit individual patient needs and to try to prevent them, by a careful introduction, slow escalation, well-considered combination and possible pre-exposure testing of patients for their tolerance, to each proposed AED. The overall problem and the profiles of the main agents are outlined from the perspective of dose-related issues. 相似文献
68.
69.
70.
Qi-Ming Wang Yi-Jun Qi Qi Jiang Yuan-Fang Ma Li-Dong Wang 《Medical oncology (Northwood, London, England)》2011,28(1):188-193
The striking 3-4:1 male predominance of esophageal squamous cell carcinoma (ESCC) has not yet been well explained. Our hypothesis
is that the changes in level of estrogen and/or subtype of estrogen receptor (ER) may exert a protective factor in esophageal
carcinogenesis and prognosis of ESCC. Radioimmunoassay (RIA) was used to determine the serum level of estradiol in healthy
cohort from high-incidence area (HIA) and low-incidence area (LIA) for esophageal cancer as well as patients with ESCC from
HIA in Henan, northern China. The ERβ expression profiling during the multi-stage progression of ESCC pathogenesis was evaluated
by immunohistochemistry (IHC). Both males and females from HIA had significant decreases of serum estradiol in high-risk subjects
predisposing for ESCC compared to healthy counterparts from LIA (P < 0.01). Furthermore, patients with ESCC from HIA developed the lowest level of estradiol (P < 0.01). ERβ expressed in precursor lesions of ESCC and changed quantitatively and qualitatively with disease progression
during the multi-stages process of esophageal carcinogenesis. High frequency of ERβ expression was correlated with less aggressive
potential of clinical behavior (P = 0.012, 0.015 for lymph node metastasis and tumor stage, respectively). This study indicates that lower serum level of estradiol
may represent higher predisposition for development of ESCC, and ERβ expression and/or nuclear location may predict better
outcome for patients with ESCC. The present results provide clues to explain the striking gender difference for ESCC, which
warrants further investigations on potential applications of estrogen or analogs in prevention of ESCC. 相似文献