1.The status quo and future prospects of the next generation sequencing technologies in clinical diagnostics
Chinese Journal of Laboratory Medicine 2017;40(7):483-485
During the past decade, tremendous progress has been made in terms of speed, read length, and throughput, along with a sharp reduction in per-base cost.Together, these advances democratized next generation sequence (NGS) and paved the way for the development of a large number of novel NGS applications in clinical diagnostics, especially in the field of non-invasive prenatal detection, rare genetic disease and cancer companion diagnostics.As technology advances, long-read single molecule sequencing began to emerge.Single cell, long-reads, transcriptome, and low cost will be the NGS direction.Due to the special nature of clinical testing, the current NGS clinical application system,including genetic counseling, testing standards, quality control, supervision, database construction etc, does not match the national conditions well and still faces a few challenges, needs to be constantly improved through the routine clinical practice in the future.
2.Molecular diagnosis in China:present status and challenges ahead
Chinese Journal of Laboratory Medicine 2016;39(7):473-476
Molecular diagnosis is rapidly developed in recent years , mainly applicated in the diagnosis of hereditary disease , infectious pathogens, tumor susceptibility and molecular typing , companion diagnosis and prognosis assessment , playing more and more important role in many diseases diagnosis and treatment.Molecular diagnosis was developed from the eighties of the last century in our country .Nowadays, the mainly applied technologies in the clinical laboratory include fluorescence in situ hybridization , quantitative PCR, microarray and DNA sequencing. These molecular technologies make up for the insufficiency of routine testing and take up a central role in the development of modern laboratory medicine . With the continuous development in transformation research of molecular technology recent years , there will be more molecular diagnostic techniques applied in clinicaldiagnosis in the future .But it still exists some drawbacks in the performance of molecular diagnosis in our country according to the current situation , such as imbalanced regional development , mismatched policies, non-standardized laboratory construction , deficiency of quality control and supervision , etc., which requires the joint effort of the government , hospital, professional association and clinical laboratory itself to promote the healthy and orderly development of molecular diagnosis.
3.ATRA combined with IFN-α2a promotes iodine uptake of FTC-133 follicular thyroid carcinoma cells
Zhen ZHAO ; Guohua SHEN ; Huawei CAI
Journal of Medical Postgraduates 2016;29(9):910-912
Objective Some drugs can effectively improve the uptake of 131 I in dedifferentiated thyroid cancer .This study was to investigate the effect of all-trans retinoic acid (ATRA) combined with interferon-α2a (IFN-α2a) on the iodine uptake and re-tention rate of FTC-133 follicular thyroid carcinoma cells . Methods FTC-133 cells were cultured in the presence of 2 μmol/L AT-RA and/or 1500 IU/mL IFN-α2a for 72 hours.The the cells were collected for measurement of the uptake and retention rate of Na 125 I. Results The Na125 I uptake of the FTC-133 cells was significantly increased after 72-hour incubation with 2μmol/L ATRA and 1500 IU/mL IFN-α2a (2423.1 ±237.5) as compared with those of the control (1279.5 ±102.8), ATRA (1438.2 ±149.6), and IFN-α2a groups (1355.3 ±198.4) (P<0.05).Statistically significant differences were observed in the retention rate of Na 125I in the FTC-133 cells at different time points in the each of the blank control , 2μmol/L ATRA, 1500 IU/mL IFN-α2a, and combination groups (P<0.01), but not in that of Na125I among these groups (P<0.05). Conclusion ATRA in combination with IFN-α2a can promote the Na125 I uptake but cannot improve the Na 125 I retention rate in FTC-133 cells.
4.Research advancement of pro-apoptotic mechanisms of GRIM-19 and its related proteins
Guohua SHEN ; Huawei CAI ; Zhen ZHAO
Journal of Medical Postgraduates 2015;(3):303-307
Cancer development is a complex process that involves multiple genetic changes and multiple signaling pathways . Recent findings show that the GRIM-19 is a novel apoptosis regulation gene , and its gene mutations and loss of protein expression have been observed in many tumor types such as urinarysystem tumor , digestive system neoplasm , which are closely related to cancer devel-opment.Thus, GRIM-19 may be a potential target for gene therapy .Pro-apoptotic mechanisms of GRIM-19 and its related proteins such as STAT3,GW112,p16INK4aare overviewed in this article.
6.Expression and role of IL-17 in nasal polyposis.
Yang SHEN ; Suling HONG ; Guohua HU
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2014;28(8):516-519
OBJECTIVE:
To study the expression of interleukin-17 (IL-17) in nasal polyps from both atopic and nonatopic patients, and its associations with histological features of polyps tissue.
METHOD:
Thirty patients with nasal polyps (NP) were included and divided into atopic and nonatopic groups according to the skin prick test. Histological characteristics were assessed by eosinophilic infiltration with HE staining. IL-17 expression in polyps tissue was detected by ELISA and RT-PCR.
RESULT:
Eosinophilic infiltration was significantly higher in atopic NP patients than in nonatopic NP patients (P < 0.01). IL-17 protein and IL-17 mRNA levels were significantly upregulated in both atopic (P < 0.01) and nonatopic (P < 0.05) patients compared with controls. Furthermore, IL-17 levels were significantly higher in the atopic group than in nonatopic group. Significantly positive correlations were found between IL-17 levels and eosinophilic infiltration in NP patients.
CONCLUSION
These results indicated that expression of IL-17 was significantly upregulated in NP patients and was especially higher in atopic NP patients, suggesting that IL-17 may play an important role in the pathogenesis of NP and atopy may contribute to NP by stimulating the production of IL-17.
Adult
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Aged
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Eosinophils
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cytology
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Female
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Humans
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Hypersensitivity, Immediate
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metabolism
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pathology
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Interleukin-17
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metabolism
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Male
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Middle Aged
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Nasal Polyps
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metabolism
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pathology
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Young Adult
7.Combination of taurine and diazepam has neuroprotective effect on focal cerebral ischemia-reperfusion in rats
Guohua WANG ; Zhenglin JIANG ; Xia LI ; Xingjuan FAN ; Lihua SHEN
Chinese Journal of Pathophysiology 2010;26(4):737-741
AIM: To observe the neuroprotective effect of combined treatment with taurine and diazepam against focal cerebral ischemia-reperfusion in rats. METHODS: Sixty male Sprague-Dawley rats were randomly divided into five groups: sham-operation group, vehicle group, taurine group (200 mg/kg, ip), diazepam group (10 mg/kg, ip) and combined treatment group (taurine 100 mg/kg+diazepam 5 mg/kg). Focal cerebral ischemia was induced by the method of middle cerebral artery occlusion (MCAO) in rats, and reperfusion was emerged by removing the thread 2 h later. The drugs were administered respectively at the time of reperfusion, and subsequently repeated once 12 h later. The animals in vehicle group were intraperitoneally injected with isodose normal saline. The neurological deficit score, the brain water content and cerebral infarction were measured 48 h after MCAO. Other 5 group animals of focal cerebral ischemia-reperfusion (n=16 in each group) were set up as mentioned above and accepted treatments 10 h after reperfusion, likewise repeated once 12 h later. Twelve animals in each group were adopted the same management as the previous 5 groups at 48 h after MCAO. The remained 4 animals in each group were sacrificed until two weeks after MCAO to observe the histopathological changes by nissl staining. RESULTS: Compared to vehicle group, the animals in combined treatment group at 2 h or 12 h after MCAO both decreased the neurological deficit score, reduced the brain water content and infarct volume (P<0.01 or P<0.05). The combined treatment significantly alleviated the neurological necrosis as well. The neuroprotective effect of the combined treatment was superior to that of using taurine or diazepam alone. CONCLUSION: These results suggest that combination of taurine and diazepam treatment has a coordinate neuroprotective effect on both the acute and chronic brain damage of focal cerebral ischemia-reperfusion.
8.Clinical characteristics and countermeasures of osteoporotic vertebral fractures treated with percutaneous vertebroplasty
Yi ZHANG ; Xiangwang HUANG ; Xiongjie SHEN ; Guohua WANG
Chinese Journal of Postgraduates of Medicine 2010;33(26):9-12
Objective To explore clinical the characteristics and countermeasures of osteoporotic vertebral fractures treated with percutaneous vertebroplasty. Methods From March 2005 to March 2008,64 patients (totally 86 vertebra) with osteoporotic vertebral fractures undergoing percutaneous vertebroplasty were retrospectively analyzed. The level of fracture was between T5 to L5. The symptomatic fractured vertebrae were determined with combination of regional pain, X-rays and MR images. The postoperative effect were evaluated by the visual analog score (VAS) and Oswestry disability index (ODI). Results All the patients were followed up 12 - 23 ( 13.40 ± 1.03 ) months. The VAS decreased from (8.3 ± 1.2) scores to bdfore surgery (2.3 ± 1.4) scores after surgery and to (2.5 ± 1.1 ) scores at the last follow-up time(P < 0.01 ). The ODI decreased from (62.0 ± 2.3 ) scores before surgery to (23.1 ± 2.5 ) scores after surgery and to ( 26.3 ±2.4) scores at the last follow-up time (P <0.01). The back pain of all patients were relieved to different degrees postoperatively. No severe complications including pulmonary embolism occurred. Conclusions The key point is to find the symptomatic fractured vertebrae not only based on preoperative X-rays but also the MR images, especially fat-compressing MR images. Only when the fractured vertebrae demonstrate low intensity on T1WI MR image and high intensity on T2WI or fat-compressing MR image can be considered new fractures. The injection should reach the new fractured part and if necessary the bilateral approaches should be considered and the injection can be separated for several steps in multi-segments fracture. PMMA should be injected after the bone cements are solid enough so as not to develop complications such as pulmonary embolism.
9.Genotyping of K-ras exon 2 codons 12 and 13 mutations in colorectal cancer by pyrosequencing
Guohua XIE ; Xiaohong YAO ; Ping WU ; Lisong SHEN
Chinese Journal of Laboratory Medicine 2012;35(7):585-592
ObjectiveTo investigate the clinical significance of pyrosequencing assay for determining K-ras mutations in exon 2 codons 12 and 13 in clinical colorectal cancer tissues.Methods Genomic DNA,extracted from K-ras mutant cell lines SW480 (homozygous,c.35G > T), DLD-1 (heterozygous,c.38G > A) and wild-type HT-29,was first used as the sequencing template respectively to test the accuracy of pyrosequencing methodology.The SW480 and DLD-1 DNA was separately mixed with wild-type HT-29 DNA in proportions of 2%,3%,5%,10%,20%,30% and 50%,the sensitivity for mutation detection was measured separately by pyrosequencing assay and directed Sanger DNA sequencing in the serial DNA mixture samples.The pyrosequencing assay results were compared with the corresponding Sanger sequencing and the datas were analysized by Fisher exact test.Pyrosequencing analysis was then performed for screening K-ras exon 2 mutations at codons 12 and 13 on DNA isolated from a panel of 30 colorectal cancer samples derived fromclinicalformalin-fixed andparaffinembedded(FFPE)tissues.ResultsCancer cell lines with known K-ras mutations ( SW480 and DLD-1 ) were readily detectable by pyrosequencing-based analysis.When the proportions of mutant colorectal cancer cell line DNA were 5% and 10% content,the mutation rates of K-ras gene detected by conventional Sanger DNA sequencing were 33.3% (4/12) and 58.3% (7/12) respectively,whereas the mutation rates detected by pyrosequencingbased assay were 91.7% (11/12) and 100%(12/12) respectively,there were significant differences between those two sequencing methodology ( P <0.05).Furthermore,we found 10 patients with K-ras exon 2 point mutations at codons 12 and 13 by pyrosequencing-based assay from 30 colorectal cancer FFPE tissues,the point mutation rate was 33.3% (10/30) and all of the mutations determined were heterozygous.The codon 12 was most frequently affected [30% (9/30)].Mutations with the highest frequency were G > A transitions [ 50% ( 5/10 ) ],followed by G > T transversions [ 30% ( 3/10 ) ].Conclusion The pyrosequencing assay provides an accurate and sensitive method for mutation screening of K-ras exon 2 codons 12 and 13 in routine diagnostic specimens,thereby allowing the selection of the cancer treatment in clinical individualized practice.
10.Experimental study on the differentiation of SHI-1 cells induced by puerariae radix flavones in vitro
Guohua ZHU ; Qi ZHANG ; Haiping DAI ; Yunliang ZHAI ; Qun SHEN
Journal of Leukemia & Lymphoma 2013;22(10):582-585
Objective To explore the possible effects on differentiation of SHI-1 cells induced by puerariae radix flavones(PRF)in vitro.Methods SHI-1 cells were treated with PRF in various concertration,then the inhibitory effects of cell proliferation were detected by MTT assay,the cell cycles were analyzed by flow cytometry(FCM),the cells reduction rates were detected by NBT reduction test,and the expression of CD11b and CD14 were tested by FCM.Results 10-50 μg/ml PRF could inhibit the proliferation of SHI-1 cells in a time-and dose-dependent manner,and the cell cycles were arrested in S phase.When SHI-1 cells were treated with 10,30 and 50 μg/ml PRF in 48 houres respectively,the NBT reduction rates of cells were increased in a dose-dependent with PRF(P<0.05),and the expression of cells surface differentiation antigen CD14 was also increased along with the concentration of PRF.Conclusion The SHI-1 cells could be induced to differentiation partially after treated with 10,30 and 50 μg/ml PRF in vitro.