Association between dense PAX1 promoter methylation and HPV16 infection in cervical squamous epithelial neoplasms of Xin Jiang Uyghur and Han women

PAX1 and SOX1 Gene Methylation as a Detection and Triage Method for Cervical Intraepithelial Neoplasia Diagnosis

INTRODUCTION

Methylation assays have demonstrated potential as dependable and high-precision approaches for identifying or triaging individuals with cervical cancer (CA) or cervical intraepithelial neoplasia (CIN). Our investigation aimed to assess the efficacy of the diagnosis and triage of the PAX1/SOX1 methylation panel in detecting CIN or CA.

METHODS

A total of 461 patients with abnormal high-risk human papillomavirus (hrHPV) or cytology test results were recruited for this study. Each patient underwent an assortment of assessments, comprising a cytology test, hrHPV test, colposcopy examination, and PAX1 and SOX1 methylation tests.

RESULTS

The extent of methylation of both genes demonstrates a positive correlation with the severity of CIN lesions and CA. To determine the correlation for patients with CIN2 or worse (CIN2+), the area under curve was 0.821 (95% CI: 0.782-0.853) for PAX1 and 0.800 (95% CI: 0.766-0.838) for SOX1, while for CIN3 or worse (CIN3+), 0.881 (95% CI: 0.839-0.908) for PAX1 and 0.867 (95% CI: 0.830-0.901) for SOX1. The PAX1/SOX1 methylation marker panel performed sensitivity and specificity of 77.16% and 91.67% for CIN2+, 84.76% and 90.50% for CIN3+, respectively. Regarding triaging hrHPV+ patients, the PAX1/SOX1 methylation test only referred 11.83% of the patients who are unnecessary for colonoscopy examination, which is comparatively lower than cytology, thereby signifying a promising triage strategy for hrHPV-positive women. Furthermore, we observed that the positive PAX1/SOX1 methylation test result for untreated CIN1 or fewer patients would result in a higher likelihood of progression upon a 24-month follow-up visit.

CONCLUSION

The present investigation demonstrates that the PAX1/SOX1 methylation marker panel exhibits favorable diagnostic performance in CIN detection and holds the potential to be employed for individual CIN tests or hrHPV-positive triage.

Aberrant Epigenetic Alteration of PAX1 Expression Contributes to Parathyroid Tumorigenesis

CONTEXT

Primary hyperparathyroidism (PHPT) results from the hypersecretion of parathyroid hormone from parathyroid tumors. A transcription factor, namely Paired box1 (PAX1), is active in parathyroid gland development.

OBJECTIVE

We aimed to study potential epigenetic-mediated mechanism of PAX1 gene in sporadic parathyroid adenomas.

METHODS

In parathyroid adenomas tissues, we analyzed the DNA methylation via bisulfite-specific polymerase chain reaction (BSP) and histone modifications via chromatin immunoprecipitation in regulating the differential expression of PAX1.

RESULTS

The results showed that mRNA and protein expression of PAX1 was significantly reduced in parathyroid adenomas. Bisulfite sequencing demonstrated hypermethylation in the promoter region of PAX1 (35%; 14/40) and lower levels of histone 3 lysine 9 acetylation (H3K9ac) were observed on the promoter region of PAX1 (6-fold; P < .004) in parathyroid adenomas. Furthermore, upon treatment with a pharmacologic inhibitor, namely 5'aza-2 deoxycytidine, in rat parathyroid continuous cells, we found re-expression of PAX1 gene.

CONCLUSION

Our study not only reveals expression of PAX1 is epigenetically deregulated but also paves a way for clinical and therapeutic implications in patients with PHPT.

PAX9 functions as a tumor suppressor gene for cervical cancer via modulating cell proliferation and apoptosis

To investigate the effect of PAX9 on the progression of cervical cancer (CC). PAX9 expression was quantified in CC tissues and adjacent normal tissues, as well as human CC cell lines and human cervical epithelial cells (HCerEpiC). PAX9-overexpression lentiviral vectors were transfected into CC cell lines, followed by the measurement of proliferation and apoptosis and the quantification of apoptosis-related proteins. In vivo, mice were subcutaneously injected with CaSki cells transfected with PAX9-overexpression lentiviral vectors and control vectors. Then, the volume and weight of tumors were measured followed by hematoxylin and eosin (HE) staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, and immunohistochemistry. PAX9 expression in the CC tissues was lower than that in the adjacent normal tissues, which was correlated with the FIGO stage, tumor size, infiltration depth, parametrium invasion, lympho-vascular space invasion tumor-positive lymph nodes, and prognosis. Furthermore, PAX9 in CC cell lines was also lower than in HCerEpiC. PAX9 inhibits the CC cell proliferation and promotes the apoptosis, with the up-regulations of caspase-3, poly(ADP-ribose) polymerase (PARP), and Bax and the down-regulation of Bcl-2. In vivo experiments demonstrated that in the PAX9 group, the tumor weight and volume were lower than those in the vector group accompanying the decreased Ki-67, cleaved-caspase-3, and Bax expressions and the increased TUNEL and Bcl-2 expression. PAX9 was lowly expressed in the CC tissues and associated with the clinicopathological characteristics and prognosis. PAX9 could inhibit proliferation of CC cell lines and promote the apoptosis, thus suppressing the tumor growth in vivo, indicating its potential therapeutic role for CC treatment.

Real time quantitative methylation detection of PAX1 gene in cervical cancer screening

INTRODUCTION

DNA methylation is currently found to be associated with the progression of cervical intraepithelial neoplasia and the development of cervical cancer. The aim of this study was to analyze the role of real time quantitative methylation detection of the PAX1 gene in cervical cancer screening.

METHODS

All eligible patients who underwent multiple detections for cervical cancer were assigned to the normal cervical group (n=21), cervical intraepithelial neoplasia I group (n=7), cervical intraepithelial neoplasia II+III group (n=12), or invasive cervical cancer group (n=14) based on pathological gradings. The methylation level of the PAX1 gene was detected using the real time quantitative methylation specific polymerase chain reaction assay and assessed by △Cp value. The diagnostic performance of PAX1 methylation detection was compared with folic acid receptor mediated diagnosis, the Thinprep cytology test, and human papilloma virus (HPV) testing.

RESULTS

The △Cp value in the invasive cervical cancer group was (6.15±4.07), significantly lower than that in the other groups (F=26.45, p<0.001). The area under the curve (AUC) of PAX1 methylation detection was 0.902 (95% confidence interval (CI) 0.817-0.986; p<0.001), and sensitivity and specificity were 92.30% and 78.60% when the cut-off value of △Cp was 13.28. The AUC of PAX1 methylation detection was notably larger compared with 0.709 for folic acid receptor mediated diagnosis (95% CI 0.568-0.849, p=0.009), 0.702 for the Thinprep cytology test (95% CI 0.559-0.844, p=0.015), and 0.655 for HPV testing (95% CI 0.508-0.802, p=0.014).

CONCLUSION

Through quantitative methylation specific polymerase chain reaction assay characterized by rapid screening and simple operation, the methylation detection of the PAX1 gene exhibited a higher diagnostic performance and may be a promising method for cervical cancer screening.