Diagnostic clinical application of two-color fluorescence in situ hybridization that detects chromosome 1 and 17 alterations to direct touch smear and liquid-based thin-layer cytologic preparations of endometrial cancers

Association of epigenetic inactivation of the WRN gene with anticancer drug sensitivity in cervical cancer cells

The Werner (WRN) gene codes for a DNA helicase that contributes to genomic stability and has been identified as the gene responsible for progeria. Recent studies have shown reduced WRN expression due to aberrant DNA hypermethylation in cancer cells. Furthermore, WRN expression is thought to affect sensitivity to DNA topoisomerase I inhibitors in cancer therapy. In this study, we examined the relationship between aberrant DNA hypermethylation of WRN and the sensitivity of cervical cancer cells to anticancer drugs. DNA was extracted from samples from 22 patients with primary cervical cancer and 6 human cervical cancer-derived cell lines. Aberrant DNA hypermethylation was analyzed by methylation-specific PCR. WRN expression in cultured cells before and after addition of 5-aza-2-deoxycytidine, a demethylating agent, was examined using RT-PCR. The sensitivity of cells to anticancer drugs was determined using a collagen gel droplet embedded culture drug sensitivity test (CD-DST). siRNA against WRN was transfected into a cervical cancer-derived cell line with high WRN expression. Changes in drug sensitivity after silencing WRN were determined by CD-DST. Aberrant DNA hypermethylation and decreased expression of WRN were detected in 7/21 cases of primary cervical cancer and in two cervical cancer-derived cell lines. These two cell lines showed high sensitivity to CPT-11, a topoisomerase I inhibitor, but became resistant to CPT-11 after treatment with 5-aza-2-deoxycytidine. Transfection of siRNA against WRN increased the sensitivity of the cells to CPT-11. Aberrant DNA hypermethylation of WRN also increased the sensitivity of cervical cancer cells to CPT-11. Therefore, epigenetic inactivation of this gene may be a biomarker for selection of drugs for the treatment of cervical cancer. This is the first report to show a relationship between the methylation of the WRN gene and sensitivity to CPT-11 in gynecological cancers.

Detection of chromosomal anomalies in endometrial atypical hyperplasia and carcinoma by using fluorescence in situ hybridization

BACKGROUND

Endometrial cancer is the most common pelvic gynecological malignancy. The diagnosis of well-differentiated endometrial adenocarcinoma, atypical hyperplasia, and hyperplasia is often challenging. The authors sought to investigate the utility of chromosomal anomalies for the detection of endometrial hyperplasia and carcinoma using multitarget fluorescence in situ hybridization (FISH).

METHODS

Samples were collected by endometrial Tao brush and processed by liquid-based cytological preparation protocol from consecutive cases to include 50 benign, 50 hyperplasia without atypia, 47 atypical hyperplasia, and 53 endometrial cancers. Each was hybridized using fluorescence-labeled DNA probes to chromosomes 1, 8, and 10. The FISH signals were enumerated in 100 cells per case, and the chromosomal anomalies were correlated with pathologic findings, including histologic diagnoses on matched endometrial tissue samples.

RESULTS

Numeric chromosomal anomalies were found in 0% (0 of 50) of benign, 20% (10 of 50) of hyperplasia, 74% (35 of 47) of atypical hyperplasia, and 87% (46 of 53) of carcinoma specimens. The mean percentage of cells with chromosomal changes was 55% in cancer specimens, which was significantly higher than that in hyperplasia without atypia (13%, P < .0001) and atypical hyperplasia (32%, P = .003). The most frequent chromosomal anomaly was gain of chromosome 1. FISH anomalies had an overall sensitivity of 81% and specificity of 90% for the detection of atypical hyperplasia and/or endometrial carcinoma. There was no association with grade of endometrial carcinoma.

CONCLUSIONS

Multitarget FISH appears to be useful for the differential diagnosis of hyperplasia, atypical hyperplasia, and endometrial adenocarcinoma, with a high level of sensitivity and specificity. It is also a potential tool for the early detection of neoplastic cells in endometrial cytology specimens. Endometrial hyperplasia with FISH-detected chromosomal anomalies may represent a clinically significant subset of cases that warrant close clinical follow-up.

Management of abnormal uterine bleeding and the pathology of endometrial hyperplasia

There are no screening tests for endometrial carcinoma, and patients typically present with abnormal uterine bleeding. This article discusses the pathophysiology and clinical work-up of abnormal uterine bleeding, and risk factors for endometrial carcinoma. Atypical complex hyperplasia and the more recently defined endometrial intraepithelial neoplasia are well recognized as precancers. Evolving knowledge of their genetic alterations provides the opportunity to develop molecular markers, so that endometrial diseases may be diagnosed at the precancerous or early invasive stage. Emerging molecular markers also provide the opportunity to develop clinically useful screening tests for the most common malignancy of the female genital tract.