Detection of hTERT mRNA in colonic brush specimens as an adjunct to cytopathologic diagnosis of colonic adenocarcinoma.

OBJECTIVE: To investigate the role of reverse transcriptase polymerase chain reaction (RT-PCR) in determining telomerase catalytic subunit (hTERT) mRNA to assist with the diagnosis of colonic adenocarcinoma (CCA) in colonic brush cytology specimens. STUDY DESIGN: Twenty-seven colonic brushes of CCA were obtained. Initial cytologic diagnoses included CCA, suspicious for CCA (SFC), atypical (ATY) and unsatisfactory. The cytologic specimens were reviewed. A homogeneous RT-PCR assay for hTERT mRNA was performed on 27 colonic brushes of CCA and 24 controls (10 negative brushes, 6 resected CCA and 8 benign colonic mucosa from resected specimens). A RT-PCR assay for beta 2-microglobulin was used as an internal control for mRNA quality. RESULTS: On review, the initial cytopathologic diagnosis of CCA was confirmed in all 7 cases. In addition, 7 of 19 initially interpreted as SFC and ATY seemed to demonstrate unequivocal cytomorphologic features of malignancy. Telomerase mRNA was more often expressed in CCA than in negative controls in both brush (30%) and resected specimens (57%) (P < .05). Seven cases with hTERT mRNA expression were initially diagnosed as CCA (three), SFC (three) and ATY (one). CONCLUSION: CCA may be underdiagnosed in brush cytopathology. The expression of hTERT mRNA may be determined by RT-PCR in brush specimens and may eventually prove to be a useful diagnostic adjunct in the interpretation of inconclusive cases of CCA. Sparse cellularity in brush specimens may result in a relatively low rate of hTERT detection in colonic brushes of CCA; inflammatory changes may contribute to a higher-than-expected rate of hTERT expression in benign colonic epithelium.

Elevated levels and distinct patterns of expression of A-type cyclins and their associated cyclin-dependent kinases in male germ cell tumors.

Aberrant expression of several key regulators controlling the G1/S phase of the cell cycle has been implicated in human male germ cell tumorigenesis. Given the critical role of cyclin A2 at both the G1/S and G2/M transitions and the essential role for cyclin A1 in male germ cell development, our present study focused on the involvement of the A-type cyclins in the transformation and progression of male germ cell tumors (GCTs). The expression of the A-type cyclins and their catalytic partners Cdk1 and Cdk2 was examined in all types and stages of human male GCTs, including carcinoma in situ(CIS), seminoma and non-seminoma GCTs, along with normal testis samples. Elevated levels of cyclin A2, Cdk1 and Cdk2 were detected in the majority of GCTs and were correlated with the invasiveness of the tumors (p < 0.05). Cyclin A1 expression was virtually undetectable in CIS and seminoma, but was aberrantly expressed in all non-seminomatous GCTs. Cyclin A2 expression was strongly correlated with that of its catalytic partners Cdk1 and Cdk2 in all types of testicular tumors examined (p < 0.05), whereas a strong correlation between cyclin A1 and Cdk1 or Cdk2 was only seen in non-seminomatous GCTs (p < 0.05). Histone kinase activities of cyclin A1/Cdks and cyclin A2/Cdks were found to be elevated in tumors. Our data suggest that aberrant expression of A-type cyclins and their Cdks is a significant factor in male germ cell tumorigenesis. The abundant ectopic expression of cyclin A1 in non-seminomatous GCTs and its absence in CIS and seminomas is likely linked to the tumor transformation and progression and may be relevant to clinical prognosis.