摘要:目的: 檢測大腸癌組織中Kras基因的突變情況以指導臨床治療。 方法 :通過提取15例大腸癌石蠟組織中的DNA并進行PCR擴增,之后采用國際金標準方法直接測序法進行檢測獲得突變信息。 結果 :15例大腸癌石蠟組織樣本中Kras有4例發生突變,突變率為266%。值得注意的是發現一個新的突變位點密碼子42,并且與密碼子12突變共存。 結論 :密碼子42的突變進一步證明Kras突變不僅局限于密碼子12,13,61,還有與密碼子12共存的42位突變。Abstract: Objective: To detect the mutation status of Kras gene in colorectal cancers and to assist the clinical treatments Methods : DNA was extracted from fifteen formalinfixed, paraffinembedded tumor samples of colorectal cancers, and then the fragments containing codons 12,13 and codon 61 were amplified by PCR The sequences were indentified by direct sequencing which is gold standard for the detection of mutation Results : In the 15 samples of colorectal cancer patients, 4 mutations were observed, with 2 in codon 12 and 2 in codon 13 Suprisingly, a novel point mutation at codon 42 of Kras was found, and coexisted with mutation in codon 12 Conclusion : Except for codons 12,13,61 mutation, Kras has other mutation at codon 42 with coexisted with codon 12 point mutation
ObjectiveTo provide the possibility to explain the relationship between genotype and phenotype, and to provide reference for the clinical treatment of Sleep-related hypermotor epilepsy (SHE). MethodsWe retrospectively analyzed the case data of the child (patient 1) diagnosed with SHE in the outpatient department of the Second Affiliated Hospital of Wenzhou Medical University in December 2017, and inquired about his family history and growth and development history. We learned that the father (patient 2) of the child had a history of epilepsy, and we also collected his medical history and growth and development history of patient 2. We carried out the basic physical examination for the two patients, and basic blood routine and blood biochemical indicators have also been done. In addition, electroencephalogram, Wechsler intelligence assessment and cranial magnetic resonance imaging were performed. After the diagnosis of patients 1 and 2, we treated them with antiepileptic drugs and make them long-term follow-up. What’more, we collected the peripheral blood of patient 1 and his father and mother, sequenced the gene, established phylogenetic tree for the mutation gene, and compared the homologous protein sequence to judge the conservation of the mutation. Moreover, in silico analysis was used to analyze the pathogenicity of the mutant gene. ResultsWe find a family with epilepsy, of whom patient 1 and his father are with epilepsy. Their clinical manifestations are atypical, and their seizures are all in sleep. After a long-term follow-up of two patients' drug treatments, it is found that patient 1 and patient 2 respond well to the drugs. Gene test shows that the mutations of DEPDC5 (c.484-1del c.484_485del) and KCNQ2 (c.1164A> T) are at the same site in both patient 1 and patient 2, and the mutation sites are first reported. What’more, the homologous protein alignment shows that the amino acids corresponding to the two mutant genes are highly conserved. ConclusionThis study mainly reports a family with sleep-related hypermotor epilepsy. Patients 1 and patient 2 have novel mutations of DEPDC5 and KCNQ2 genes. In the long-term follow-up of this study, it is found that the patients are effective the antiepileptic drugs.
ObjectiveTo explore the action of dominant-negative effect on mutant insulin gene-induced diabetes.Methods293T cells were transfected with a recombinant plasmid containing mutant preproinsulinogen complementary DNA (cDNA) and a recombinant plasmid containing human wild-type preproinsulinogen cDNA. There were 5 mutant groups which mutant preproinsulins respectively bear substitutions V(A3)L, C(A7)Y, R(SP6)H, G(B8)S or G(C28)R. Wild-type mouse preproinsulin and wild-type human preproinsulin were co-transfected as normal control group. After 48 hours, medium and cells were collected. Human proinsulin were detected by human-specific proinsulin radioimmunoassay.ResultsCompared with the control group [(135.84±1.89) pmol/L], human proinsulin levels in medium of C(A7)Y group [(29.28±6.85) pmol/L] and G(B8)S group[(33.62±10.52) pmol/L] decreased significantly (P<0.01). There was no significant difference in human proinsulin level between the other groups and the control group (P>0.05).ConclusionMutants C(A7)Y and G(B8)S induce the dominant-negative effect on co-existing wild-type proinsulin.
ObjectiveTo summarize the research progress of KRAS mutation in pancreatic tumorigenesis and therapy.MethodThe research progress of KRAS mutation in pancreatic tumorigenesis and therapy were summarized by reading the domestic and international literatures published in recent years.ResultsPancreatic cancer had the title of " king of cancer”. More than 90% of pancreatic cancer patients had KRAS mutation. KRAS had a complex relationship with pancreatic cancer through downstream signaling pathways, including Raf (rapidly accelerated fibrosarcoma)-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK), phosphatidylinositol-4, 5-bisphosphate 3-kinase (PI3K)-protein kinase B (AKT), and RalGDS-Ral. Although basic research on pancreatic cancer was deepening, there was still a lack of effective molecular targeted drugs.ConclusionsKRASgene plays an important role in the occurrence of pancreatic cancer. The treatment associated with KRAS mutation provides a more effective prognostic possibility for pancreatic cancer patients.
Purpose
To investigate mitochondrial DNA (mt-DNA) mutations in optic neuritis of unknow reason (ONUR) and to assess the pathogenic and differential diagnostic values of screening for mt-DNA mutations in ONUR.
Method
Thirty patients with ONUR were screened for mt-DNA mutations by using SSCP,mutation-specific primer PCR and sequencing.
Results
mt-DNA mutations were found in 12 out of the thirty patients.All of the mutations were at 11778 position,but no one at 3460 and 15257.
Conclusions
Quite a number of patients (12/30,40%) with ONUR were caused actually by mt-DNA mutation.Screening for mt-DNA mutation in these patients has a pathogenic and differential diagnostic significance.
(Chin J Ocul Fundus Dis,2000,16:78-79)
Objective To identify and observe the pathogenic gene variant and clinical phenotype in a family with Leber congenital amaurosis (LCA). MethodsA retrospective clinical study. Two patients and four family members from one LCA family (type 7), diagnosed via genetic testing at the First Affiliated Hospital of Xi'an Jiaotong University in January 2024 were included. Detailed patient and family histories were collected. All patients underwent examinations including best-corrected visual acuity (BCVA), intraocular pressure, color fundus photography, fundus autofluorescence (FAF), flash visual evoked potential (F-VEP), full-field electroretinography (ff-ERG), and optical coherence tomography (OCT). Family members underwent BCVA and color fundus photography examinations. Peripheral venous blood (5 ml) was collected from the patients and the four family members for genomic DNA extraction. High-throughput sequencing was used to screen for pathogenic gene variants. Identified variants were verified by Sanger sequencing. All variants were classified according to the American College of Medical Genetics and Genomics (ACMG) guidelines. Bioinformatics software including Mutation Taster, Polyphen-2, PROVEAN, and REVEL was used to analyze the pathogenicity of the variants. Results The proband (Ⅱ-2), a 14-year-old female, was born to consanguineous parents (first cousins). Her BCVA was 0.1 in both eyes; intraocular pressure was normal; the anterior segments showed no significant abnormalities. Color fundus photography showed waxy optic discs and a "coin-shaped," "salt-and-pepper" appearance in the retina. FAF revealed large areas of hypoautofluorescence in the macular region. OCT showed shallowing or disappearance of the foveal, disorganized retinal layers, and absence of the ellipsoid zone. F-VEP showed recordable P2 waves with no significant delay in peak time but slightly reduced amplitude. ff-ERG showed significantly reduced or non-detectable amplitudes of the scotopic and photopic a- and b-waves. The proband's elder sister (Ⅱ-1) had similar BCVA and fundus findings. The proband's parents (Ⅰ-1, Ⅰ-2), younger brother (Ⅱ-3), and younger sister (Ⅱ-4) showed no significant ocular phenotypic abnormalities. Genetic testing revealed that the proband and her elder sister were homozygous for the CRX gene variant c.122G>A:p.Arg41Gln. The proband's father, mother, and younger brother were heterozygous carriers of the same CRX variant; the younger sister showed no variation at this locus. Based on the clinical presentation, ff-ERG, and genetic test results, the final diagnosis was LCA type 7. According to ACMG guidelines, the c.122G>A variant was classified as likely pathogenic. Mutation Taster and Polyphen-2 software predicted the variant to be damaging; the REVEL score was 0.929, indicating a likely pathogenic variant. Conclusions The homozygous CRX gene variant c.122G>A:p.Arg41Gln causes autosomal recessive LCA type 7 in this family. LCA is characterized by early onset and severe visual impairment.
Vigilance is defined as the ability to maintain attention for prolonged periods of time. In order to explore the variation of brain vigilance in work process, we designed addition and subtraction experiment with numbers of three digits to induce the vigilance to change, combined it with psychomotor vigilance task (PVT) to measure this process of electroencephalogram (EEG), extracted and analyzed permutation entropy (PE) of 11 cases of subjects' EEG and made a brief comparison with nonlinear parameter sample entropy (SE). The experimental results showed that:PE could well reflect the dynamic changes of EEG when vigilance decreases, and has advantages of fast arithmetic speed, high noise immunity, and low requirements for EEG length. This can be used as a measure of the brain vigilance indicators.
ObjectiveTo investigate the correlation between different RAS/BRAF mutation sites and the clinicopathological characteristics, metastatic sites, and prognosis of patients with colorectal cancer. MethodsA retrospective analysis was conducted on the clinicopathological data of 415 patients with stage Ⅰ –Ⅲ microsatellite stability (MSS) colorectal cancer who underwent radical surgery at the Department of Colorectal Surgery, The First Affiliated Hospital of Zhejiang University, and the Department of General Surgery, Gansu Provincial People’s Hospital, from March 1, 2017, to October 1, 2022, and had next-generation sequencing data. According to the presence and sites of RAS/BRAF mutations, patients were divided into five groups: RAS/BRAF wild-type group, KRAS G12 codon mutation group, KRAS G13 codon mutation group, BRAFV600E mutation group, and other RAS codon mutation group. The clinicopathological characteristics and prognostic differences between the four groups of RAS/BRAF mutant colorectal cancer patients and the RAS/BRAF wild-type colorectal cancer patients were compared. ResultsAmong stage Ⅰ –Ⅲ MSS colorectal cancer patients, there were 166 cases (40.0%) of wild-type RAS/BRAF without mutation, 124 cases (29.9%) of KRAS G12 mutation, 55 cases (13.3%) of KRAS G13 mutation, 23 cases (5.5%) of BRAFV600E mutation, and 47 cases (11.3%) of other RAS codon mutations. Clinicopathological characteristics analysis revealed that BRAFV600E mutation was associated with mucinous adenocarcinoma (P=0.033). Compared with the wild-type group, KRAS G12 mutation could increase the probability of metachronous lung metastasis (P=0.003) and reduce the probability of metachronous liver metastasis (P=0.013); the KRAS G13 mutation and other RAS mutations could increase the probability of metachronous lung metastasis (P=0.004, P=0.006). Univariate and multivariate Cox proportional hazards regression analysis showed that among the RAS/BRAF codon mutations, only KRAS G13 mutation was an independent prognostic factor for poor prognosis in stage Ⅰ –Ⅲ colorectal cancer. ConclusionsDifferent RAS/BRAF gene codon mutations are associated with distinct clinicopathological characteristics and organ metastatic sites in colorectal cancer. KRAS G13 codon mutation is an independent prognostic factor for poor prognosis in stage Ⅰ –Ⅲ colorectal cancer. It is recommended that routine detection of RAS/BRAF gene site mutations should be performed in stage Ⅰ –Ⅲ colorectal cancer patients to guide the follow-up management and help clinicians make rational clinical decisions after tumor recurrence.
ObjectiveTo investigate research advance on the value of B-type RAF kinase (BRAF) gene mutation assisted diagnosis of papillary thyroid cancer (PTC) in thyroid nodule.MethodThe recent literatures on the BRAF gene mutation and its combination with fine needle aspiration cytology (FNAC) in the diagnosis of benign and malignant thyroid nodules and PTC were collected and reviewed.ResultsThe BRAFV600E gene mutation was the most common type of gene mutation in the genetic molecule of PTC. The combination of the FNAC and BRAF gene mutation detection could improve the diagnostic value of the benign and malignant thyroid nodules, especially the diagnostic accuracy of PTC. However, the negative detection of BRAF gene mutation did not rule out the possibility of PTC. It still remained controversial that the detection of BRAF gene mutation could differentiate between the benign and malignant thyroid nodules.ConclusionsBRAF gene mutation detection has different diagnostic values in different types of thyroid nodules. It has considerable diagnostic value in thyroid nodules with high BRAF mutation incidence (suspicious for malignancy, undetermined significance or follicular lesion of undetermined significance nodules) while presents false negative result in thyroid nodule with very low mutation incidence category to a large extent. BRAF gene detection might become a specific diagnostic molecular marker to promote diagnosis accuracy of PTC.
ObjectiveTo evaluate effect of RAS gene mutation after liver metastasis resection on overall survival (OS) and disease-free survival (DFS) for patients with colorectal cancer combined with liver metastasis. MethodsA comprehensive and systematic literature search in the PubMed and other databases was conducted, with the final search ending on January 5, 2022. The impact of RAS gene mutation after liver metastasis resection on survival of patients with colorectal cancer combined with liver metastasis was analyzed by the Stata 12.0 software and Review Manager version 5.3 software, meanwhile which were analyzed according to subgroups, including study type (retrospective and prospective studies), region (Asian and European), and number of RAS gene mutation sites (>2 and ≤2). ResultsA total of 26 studies with 13 356 patients were included. The integrated analysis results showed that the patients with RAS mutations had statistically shorter OS [HR=1.54, 95%CI (1.43, 1.65), P<0.001] and DFS [HR=1.32, 95%CI (1.19, 1.44), P<0.001] as compared with RAS wild-type. Except the 1-year overall survival rate, the 2–5-year overall survival rate and 1–5-year disease-free survival rate of patients with RAS gene mutation were statistically lower than those of patients with RAS wild-type (P<0.05). The results of subgroup analysis showed that no matter retrospective and prospective studies, as well as studies in Asian and European countries, it was found that the OS and DFS for patients with RAS gene mutation were shorter than those of patients with wild-type (P<0.05); At the same time, subgroup analysis of the number of RAS gene mutation sites showed that OS and DFS of patients with number of mutation sites >2 were shortened as compared with ≤2 (P<0.05). ConclusionFrom the overall analysis results, the survival of patients with RAS gene mutation after liver metastasis resection is worse than that of patients with RAS wild-type for patients with colorectal cancer combined with liver metastasis.