Research progress of optic atrophy 1-mediated mitochondrial dynamics in skeletal system diseases / 中国修复重建外科杂志

OBJECTIVE@#To review the research progress of mitochondrial dynamics mediated by optic atrophy 1 (OPA1) in skeletal system diseases.@*METHODS@#The literatures about OPA1-mediated mitochondrial dynamics in recent years were reviewed, and the bioactive ingredients and drugs for the treatment of skeletal system diseases were summarized, which provided a new idea for the treatment of osteoarthritis.@*RESULTS@#OPA1 is a key factor involved in mitochondrial dynamics and energetics and in maintaining the stability of the mitochondrial genome. Accumulating evidence indicates that OPA1-mediated mitochondrial dynamics plays an important role in the regulation of skeletal system diseases such as osteoarthritis, osteoporosis, and osteosarcoma.@*CONCLUSION@#OPA1-mediated mitochondrial dynamics provides an important theoretical basis for the prevention and treatment of skeletal system diseases.

Analysis of Coexisting Gene with NRAS in Acute Myeloid Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the coexisting mutations and clinical significance of Homo sapiens neuroblastoma RAS viral oncogene homolog (NRAS) gene in acute myeloid leukemia (AML) patients.@*METHODS@#High-throughput DNA sequencing and Sanger sequencing were used to detect 51 gene mutations. The occurrence, clinical characteristics and treatment efficacy of coexisting genes with NRAS were investigated.@*RESULTS@#A total of 57 NRAS mutations (17.5%) were detected in 326 patients with AML. Compared with the patients in NRAS non-mutation group, patients in the mutant group were younger (P=0.018) and showed lower platelet count (P=0.033), but there was no significant difference in peripheral leukocyte count, hemoglobin, and sex. For FAB classification, NRAS mutation and M2 subtype showed mutually exclusive (P=0.038). Among 57 patients carried with NRAS mutation, 51 (89.5%) patients carried with other gene mutations, 25 (43.9%) carried with double gene mutations, 10 (17.5%) carried with 3 gene mutations, and 16 (28.1%) corried with ≥ 4 gene mutations. The most common coexisting gene mutation was KRAS (24.6%, 14/57), followed by FLT3-ITD (14.0%, 8/57), RUNX1 (12.3%, 7/57), NPM1 (10.5%, 6/57), PTPN11 (10.5%, 6/57), DNMT3A (10.5%, 6/57) and so on. The age (P=0.013, P=0.005) and peripheral platelet count (P=0.007, P=0.021) of patients with NPM1 or DNMT3A mutations were higher than those of the patients with wild type, but there was no significant difference in peripheral leukocyte count and hemoglobin. Also, there was no significant difference in age, peripheral leukocyte count, hemoglobin, and peripheral platelet count between the patients in KRAS, FLT3-ITD, RUNX1 or PTPN11 mutant group and the wild group. Patients with FLT3-ITD mutations showed a lower complete remission (CR) rate (P=0.044). However, there was no significant difference in CR rate between the patients with KRAS, NPM1, RUNX1, PTPN11 or DNMT3A mutations and the wild group. The CR rate of the patents with single gene mutation, double gene mutations, 3 gene mutations, and≥ 4 gene mutations were decreased gradually, and there was no significant difference in CR rate between pairwise comparisons.@*CONCLUSION@#The mutation rate of NRAS mutation is 17.5%, 89.5% of AML patients with NRAS mutation coexist with additional gene mutations. The type of coexisting mutations has a certain impact on clinical characteristics and CR rate of patients with AML.

Complete screening of exons 2, 3, and 4 of kras and nras genes reveals a higher number of clinically relevant mutations than food and drug administration quantitative polymerase chain reaction-based commercial kits

Abstract Background: The presence of clinically relevant mutations in KRAS and NRAS genes determines the response of anti-epidermal growth factor receptor antibody therapy for metastatic colorectal cancer (mCRC). The only quantitative polymerase chain reaction (qPCR)-based diagnostic tests approved by the Food and Drug Administration (FDA) screen merely for mutations in codons 12 and 13 of KRAS. Objective: The objective of the study was to study the frequency of clinically relevant mutations in KRAS and NRAS genes that are not included in FDA-approved qPCR tests. Methods: Formalin-fixed paraffin-embedded tumor specimens from 1113 mCRC Mexican patients from different health institutions across the country were analyzed by Sanger sequencing for KRAS mutations in exons 2, 3, and 4. Furthermore, 83 were analyzed in exons 2, 3, and 4 of NRAS. Results: From the specimens tested for KRAS, 33.69% harbored a mutation. From these, 71.77% were in codon 12 and 27.69% in codon 13 (both located in exon 2). Codons 59 (exon 3) and 146 (exon 4) accounted for the remaining 0.54%. From the 83 specimens, in which NRAS was analyzed, three mutations were found in codon 12 (3.61%). Approximately 6% of RAS mutated specimens would have been falsely reported as RAS wild type if an FDA-approved qPCR diagnostic test had been used. Conclusions: While these kits based on qPCR can be very practical and highly sensitive, their mutation coverage ignores mutations from poorly genetically characterized populations.

Association between MFN2 gene polymorphisms and the risk and prognosis of acute liver failure: a case-control study in a Chinese population

This study aimed to determine the role of mitofusin 2 (MFN2) gene polymorphisms in the risk and prognosis of acute liver failure (ALF). A total of 298 blood samples were collected from 138 ALF patients (case group) and 160 healthy participants (control group). Coagulation function, glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), total bilirubin (TB), blood ammonia and lactic acid (LA) were measured. The predictive evaluation of MFN2 gene polymorphisms in the risk and prognosis of ALF patients was estimated using Kaplan-Meier survival analysis, haplotype analysis, binary logistic regression analysis and Cox regression analysis. Higher levels of GPT, GOT, TB, blood ammonia and LA were observed in ALF patients with the GG genotype of rs873457 or the TT genotype of rs4846085 than in those with the CC genotype of these two SNPs. The GTACAGC and GTGTGGC haplotypes were a protective factor and a risk factor for ALF, respectively. Blood ammonia and LA levels were independent risk factors and the CC genotype of rs873457 and the CC genotype of rs4846085 were protective factors for ALF. ALF patients with the GG genotype of rs873457 or the TT genotype of rs4846085 had a lower survival rate than those with other genotypes of these two SNPs. The rs4846085 and rs873457 polymorphisms were both independent factors affecting the prognosis of ALF patients. MFN2 gene polymorphisms (rs873457, rs2336384, rs1474868, rs4846085 and rs2236055) may be associated with ALF and the rs873457 and rs4846085 polymorphisms are correlated with the risk and prognosis of ALF.

Radiologic and Pathologic Findings of a Follicular Variant of Papillary Thyroid Cancer with Extensive Stromal Fat: A Case Report

Thyroid cancer may have small adipose structures detected by microscopy. However, there are no reports of thyroid cancer with gross fat evaluated by radiological methods. We reported a case of a 58-year-old woman with a fat containing thyroid mass. The mass was hyperechoic and ovoid in shape with a smooth margin on ultrasonography. On computed tomography, the mass had markedly low attenuation suggestive of fat, and fine reticular and thick septa-like structures. The patient underwent a right lobectomy. The mass was finally diagnosed as a follicular variant of papillary thyroid cancer with massive stromal fat.

NRAS Mutations in de novo acute leukemia: Prevalence and clinical significance.

The activating mutations of the Ras gene or other abnormalities in Ras signaling pathway lead to uncontrolled growth factor-independent proliferation of hematopoietic progenitors. Oncogenic mutations in NRAS gene have been observed with variable prevalence in hematopoietic malignancies. In the present study, NRAS mutations were detected using bidirectional sequencing in 264 acute leukemia cases — 129 acute lymphocytic leukemia (ALL) and 135 acute myeloid leukemia (AML) and 245 age- and gender-matched controls. Missense mutation was observed only in the 12th codon of NRAS gene in 4.7% of AML and 3.16% of ALL cases. The presence of NRAS mutation did not significantly influence blast % and lactate dehydrogenase (LDH) levels in AML patients. When the data were analyzed with respect to clinical variables, the total leukocyte count was elevated for mutation positive group, compared to negative group. In AML patients with NRAS mutations, 60% failed to achieve complete remission (CR), as compared to 34.8% in mutation negative group. These results indicated that NRAS mutations might confer poor drug response. In AML, disease free survival (DFS) in NRAS mutation positive group was lesser, compared to mutation negative group (9.5 months vs. 11.68 months). In ALL patients, DFS of NRAS mutation positive group was lesser than mutation negative group (9.2 months vs. 27.5 months). The CR rate was also lower for mutation-positive patients group, compared to mutation-negative group. In conclusion, these results suggested that presence of NRAS mutation at 12th codon was associated with poor response and poorer DFS in both ALL and AML.

A Novel 5'-Uncoding Region -1248 A>G Variation of Mitofusin-2 Gene Is Associated with Hypertension in Chinese

PURPOSE: Mitofusin2 gene (Mfn2, also named Hyperplasia suppressive gene, HSG) is very important in the origin and development of hypertension. However, the mechanism of Mfn2/HSG expression regulation was not uncovered. This study was designed to explore the association of a novel 5'-uncoding region (UCR) -1248 A>G variation of HSG/Mfn2 gene and hypertension. MATERIALS AND METHODS: 472 healthy, normotensive subjects [normotension (NT) group], 454 prehypertensive subjects [prehypertension (PH) group] and 978 hypertensive patients [essential hypertension (EH) group] were screened for an association study between 5'-UCR -1248 A>G of Mfn2/HSG and hypertension by polymerase chain reaction and DNA sequencing after venous blood was drawn and DNA was extracted. RESULTS: When comparing the A and G frequency in EH, PH and NT groups, in total, NT group significantly had higher A frequency than in PH group [odds ratio (OR)=1.605, confidence interval (CI) 95%=1.063-2.242, p=0.025] and EH group (OR=5.395, CI 95%=3.783-7.695, pG variation was significantly related with blood pressure level (B=-1.271, Wald=40.914, CI 95%=-1.660 - -0.881, pG variation of Mfn2/HSG gene was a novel variation and may be associated with hypertension in Chinese.

Identification of GTPase genes in the protozoa parasites Trypanosoma cruzi and Leishmania amazonensis

A PCR based assay was designed in order to amplify putative ras gene sequences of the GTPase superfamily eventually present in Leishmania amazonensis and Trypanosoma cruzi. A set of primers corresponding to the conserved motifs G1 and G3 of the GTP binding proteins was synthesized. Sequencing of six PCR products (three from Leishmania and three from Trypanosoma) identified, however, two other different GTPases. The 270 bp L. amazonensis clone, pLef-11, shared an amino acid identity of around 80 percent with an eukaryotic elongation factor 1a of protein synthesis. On the other hand, the 168 bp T. cruzi clone, pTCr1, demonstrated over 60 percent amino acid identity to ras-related proteins of the rab-YPT-SEC4 family involved in control of vesicular traffic. To our knowledge, this is the first report of GTP binding protein genes in trypanosomatids