1.Construction of fused recombinant vector of EGFR gene containing G719S and T790M by overlap PCR
Weilei DONG ; Huahua XIANG ; Hua PENG ; Yongqing GONG ; Jing ZHOU ; Hongquan ZHANG ; Zifen GUO
Chinese Journal of Clinical Laboratory Science 2018;36(2):139-141,147
Objective To construct the recombinant pMD19-exon18-exon20 plasmid containing locus G719S and T790M of EGFR gene associated with cervical cancer,which may provide a template for preparing the mutant recombinant vector of EGFR gene.Methods Using the healthy human genome DNA as templates,the segments of exon 18 and exon 20 of EGFR gene were amplified by two pairs of specific primers which were designed based on the sequences of overlapping and complementary area.The amplified segments were linked by overlap PCR.The products of linked exon18-exon20 were further inserted into the vector pMD19-T.The constructed recombi nant pMD19-exon18-exon20 plasmid was finally transformed into competent cells E.coli DH5α and then identified by PCR with bacterial solution and genome sequencing.Results The amplified fragments of exon18 and exon20 were clearly appeared at 778 bp and 596 bp and the fused product of exon18-exon20 was showed at 1 374 bp on agarose gel electrophoresis.The recombinant plasmid of fusion EGFR gene was consistent with the expected results via bacterial PCR assay and DNA sequencing.Conclusion We successfully fused the segments of exon18 with exon20 and constructed the recombinant expression vector of EGFR gene by using overlap PCR method.
2.Feasibility Evaluation of using PAX1/JAM3 methylation markers as cervical cancer screening for female self-collected samples
Furong YU ; Jiezhi MA ; Xi ZHOU ; Genlin LI ; Jiaqi PENG ; Ping LI ; Fei ZENG ; Xiaobing XIE ; Weilei DONG
Chinese Journal of Laboratory Medicine 2024;47(4):419-427
Objective:To explore the application value of PAX1/JAM3 methylation detection by cervical self-collected specimen in cervical cancer screening and the management of premenopausal and postmenopausal women.Method:This study is a single center cross-sectional study. From January 2023 to November 2023, cervical self-collected and physician-collected specimens at the colposcopy clinic were detected the PAX1/JAM3 methylation (PAX1 m/JAM3 m) testing. The consistency between self-collected and physician-collected specimens for PAX1 m/JAM3 m detection were compared based on histopathology. In addition, the clinical efficacy of methylation detection with high-risk human papillomavirus (hrHPV), liquid-based cytology (LBC), and their combination for cervical cancer screening were compared in the study. Results:A total of 301 women were recruited to undergo referral colposcopy examination, and statistical analysis was conducted on 272 women with pathological and diagnostic information. Among them, 102 cases (37.5%) were diagnosed as normal cervical tissue or chronic cervicitis, 72 cases (26.4%) were cervical intraepithelial neoplasia grade 1 (CIN1), 43 cases (15.8%) were CIN2, 29 cases (10.7%) were CIN3, and 26 cases (9.6%) were cervical cancer. According to the minimum quantity formula, they were divided into a consistency cohort of 81 participants and a validation cohort of 191 participants. The consistency between cervical self-collected and physician-collected specimens for detecting PAX1 m/JAM3 m. Results from spearman correlation analysis showed a positive correlation between the self-collected and physician-collected results of PAX1 m/JAM3 m detection, and the correlation coefficient R values are 0.858 ( P<0.001) and 0.828 ( P<0.001). The sensitivity and specificity of PAX1 m/JAM3 m detection for diagnosing CIN2 or more severe lesions (CIN2+) were 77.6% [95% confidence interval ( CI) 65.3%-86.4%] and 87.2% (95% CI 80.5%-91.9%), respectively. In clinical performance comparison, the sensitivity of PAX1 m/JAM3 m combined with HPV16/18 detection, 89.7% (95% CI 79.2%-95.2%), was the same as that of hrHPV detection in CIN2+and 96.0% (95% CI 80.4%-99.3%) in CIN3+, which is higher than 92.0% (95% CI 75.0%-97.8%) of hrHPV and 82.6% (95% CI 62.9%-93.0%) of LBC or the combination of sPAX1 m/JAM3 m and LBC low-grade and higher squamous intraepithelial lesion testing [87.0% (95% CI 67.9%-95.5%)]. Conclusions:Self-collected specimens by women for detection of PAX1 and JAM3 methylation as a promising screening tool for cervical cancer has operational and clinical feasibility. The methylation test can optimize the current cervical cancer screening plan, reduce the number of referral women with false positive diagnosis to colposcopy, and is of great significance for reducing fertility protection and preventing missed diagnosis in women of childbearing age.
3. Correlation between progesterone receptor G1978T polymorphism and endometrial cancer
Jing ZHOU ; Chen ZHOU ; Ke LIAO ; Ailin QIU ; Zifen GUO ; Weilei DONG ; Jing ZHOU
Chinese Journal of Clinical Pharmacology and Therapeutics 2023;28(4):400-406
To explore the relationship between progesterone receptor (PGR) gene G1978T polymorphism and endometrial carcinoma. METHODS: After searching PubMed, EMBASE, Wan-fang and CNKI databases for literatures on PGR G1978T genotyping of endometrial cancer patients, the data were extracted and odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using STATA15. The whole blood samples of endometrial carcinoma cases (EC group) and normal women (control group) were collected. Allelic-specific primers matching G1978T wild type G allele and mutant type T allele were designed with 3' terminal phosphorothioate modification, and the two-directional primer extension was performed using Exo + polymerase to genotype PGR gene G1978T polymorphism and Sanger sequencing was used to verify the genotype. RESULTS: PGR gene G1978T mutation was marginally associated with endometrial carcinoma risk (ORper allele =1.10, 95%CI=0.98-1.24, P= 0.072). At the same time, only 1 normal blood samples were found with PGR gene G1978T mutation, and the differences in genotypes and allele frequency between the case group and the control group were not statistically significantP>0.05. CONCLUSION: The G1978T polymorphism of the PGR gene maybe not be associated with the risk of endometrial carcinoma.
4.Association of EGFR gene G719S and T790M mutations with cervical cancer.
Huahua XIANG ; Jing ZHOU ; Hua PENG ; Weilei DONG ; Yongqing GONG ; Hongquan ZHANG ; Zifen GUO
Chinese Journal of Medical Genetics 2019;36(4):376-379
OBJECTIVE:
To establish a rapid and accurate "on/off" switch technique consisted of 3'-phosphorothioate-modified allele-specific primers and exo+ polymerase to screen the G719S and T790M mutations of epidermal growth factor receptor (EGFR) gene. The switch was used to identify cervical cancer patients who are sensitive to tyrosine kinase inhibitor (TKI).
METHODS:
Allele-specific primers targeting recombinant wild-type and mutation-type templates were designed with 3' terminal phosphorothioate modification. Two-directional primer extension was carried out using Pfu polymerase. The G719S and T790M mutations were detected by the technique among cervical cancer tissues. The results were verified by Sanger sequencing.
RESULTS:
No mutation was detected among the 80 cervical cancer cases, and the results were consistent with that of Sanger sequencing. No significant difference was found between the frequencies of the G719S and T790M mutations between the patient and the control groups (P> 0.05).
CONCLUSION
A sensitive "on/off" switch technique for detecting the two EGFR mutations was established. The G719S and T790M mutations are not associated with cervical cancer.
Carcinoma, Non-Small-Cell Lung
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Drug Resistance, Neoplasm
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ErbB Receptors
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genetics
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Female
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Genes, erbB-1
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Humans
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Lung Neoplasms
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Mutation
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Protein Kinase Inhibitors
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Uterine Cervical Neoplasms
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genetics