Histochemical investigation of cervical intraepithelial neoplasia

HPV16 E6 Promotes the Progression of HPV Infection-Associated Cervical Cancer by Upregulating Glucose-6-Phosphate Dehydrogenase Expression

Cervical cancer, which is significantly associated with high-risk human papillomavirus (HPV) infection, currently ranks the fourth most common cancer among women worldwide. Previous literature reported that the elevated expression of G6PD was significantly correlated with the occurrence and deterioration of human cervical cancer, especially with the cervical cancer with HPV16 and HPV18 infection. In this study, we verified that G6PD expression has a strong positive correlation with HPV16 E6 levels in cervical cancer tissues and cells. In addition, regulating the expression of HPV16 E6 significantly affected the proliferation, apoptosis, migration, and invasion in the cervical cancer HeLa cells, as well as the transcript and protein levels of G6PD. The luciferase reporter assay and ChIP assay proved that HPV16 E6 stimulated the transcription of G6PD mRNA and subsequently enhanced the expression of G6PD through directly binding to the specific sites in the promoter of G6PD. Our findings reveal that HPV16 E6 is a novel regulatory factor of G6PD. Furthermore, by regulating the expression of G6PD, HPV16 E6 might promote the proliferation and migration potential, and inhibit apoptosis of cervical cancer cells, which ultimately contributed to the progression and metastasis of cervical cancer.

1p36.22 region containing PGD gene is frequently gained in human cervical cancer

AIM

To identify commonly occurring DNA copy number alterations in Korean cervical cancers.

METHODS

DNA copy number alteration was screened by whole-genome array comparative genomic hybridization (CGH) analysis. For the array CGH discovery, genomic DNA from five cervical cancers and 10 normal cervical tissues were examined. For the independent validation of the most significant chromosomal alteration (1p36.22, PGD gene), 40 formalin-fixed paraffin-embedded cervical tissue samples were collected; 10 of them were used for quantitative polymerase chain reaction and the other 30 samples were used for immunohistochemical analysis. Chromosomal segments differently distributed between cancers and normal controls were determined to be recurrently altered regions (RAR).

RESULTS

A total of 13 RAR (11 RAR losses and two RAR gains) were defined in this study. Of the 13 cervical cancer-specific RAR, RAR gain in the 1p36.22 locus where the PGD gene is located was the most commonly detected in cancers (P = 0.004). In the quantitative polymerase chain reaction replication, copy number gain of the PGD gene was consistently identified in cervical cancers but not in the normal tissues (P = 0.02). In immunohistochemical analysis, PGD expression was significantly higher in cervical cancers than normal tissues (P = 0.02).

CONCLUSION

Our results will be helpful to understand cervical carcinogenesis, and the PGD gene can be a useful biomarker of cervical cancer.

Increased activity of 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase in purified cell suspensions and single cells from the uterine cervix in cervical intraepithelial neoplasia

The activities of 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase have been measured in squamous epithelial cells of the uterine cervix from normal patients and cases of cervical intraepithelial neoplasia (CIN). A biochemical cycling method, which uses only simple equipment and is suited to routine use and to automation, was applied to cells separated by gradient centrifugation. In addition, cells were examined cytochemically, and the intensity of staining in the cytoplasm of single whole cells was measured using computerised microcytospectrophotometry. Twenty per cent of cells in samples from normal patients (n=61) showed staining intensities above an extinction of 0.15 at 540 nm, compared to 71% of cases of CIN 1 (n=14), 91% of cases of CIN 2 (n=11) and 67% of cases of CIN 3 (n=15). The cytochemical data do not allow definitive distinctions to be made between different grades of CIN whereas the biochemical assay applied to cell lysates shows convincing differences between normal samples and cases of CIN. There are no false negatives for CIN 3 (n=14) and CIN 2 (n=10) and 11% false negatives for CIN 1 (n=9) and 14% of false positives for normal cases (n=21). The results of this preliminary study with reference to automation are discussed [corrected].

Distribution of epithelial antigens in the human uterine cervix: a review

Epithelial antigen immunostaining in the uterine cervix has been claimed to be helpful in the identification and classification of rare lesions, evaluation of basement membrane integrity, study of atypical condylomas, immunodetection of proliferating processes and early diagnosis of malignant transformation. The present review attempts to demonstrate the potential value of immunohistological techniques as a means of identifying normal and abnormal patterns of antigenic expression in cervical epithelium.