The clinical value of digene hybrid capture HPV DNA testing in a referral-based population with abnormal pap smears.

PURPOSE OF INVESTIGATION: The hybrid capture human papillomavirus (HPV) DNA assay is offered by the manufacturer to assist clinicians with patients with ASCUS pap smear results to assess the risk factor and to potentially direct follow-up of these patients. In our practice, a gynecologic oncology practice that has a referral based population with abnormal pap smears, our purpose was to evaluate the patients referred with all grades of abnormal cervical cytology. METHODS: One hundred consecutive patients who were referred for evaluation of abnormal cervical cytology: atypical squamous cells of undetermined significance (ASCUS); low-grade squamous intraepithelial lesion (LGSIL); high-grade squamous intraepithelial lesion (HGSIL); or squamous cell carcinoma (SCC) were evaluated by repeat pap smear, hybrid capture HPV DNA analysis and colposcopy. Colposcopic findings were recorded, and if appropriate, cervical biopsies were performed. Hybrid capture results were correlated with histologic and cytologic findings. Using histopathologic diagnosis as the reference standard, the sensitivity and positive predictive value of pap smear and high risk HPV were calculated. The Kappa test was used to correlate colposcopic and histopathologic findings. RESULTS: Repeat pap smears at the time of initial consultation demonstrated 25 patients with normal results, 39 with LGSIL, 30 with HGSIL, 1 SCC and 5 ASCUS. Seventy-eight patients underwent cervical biopsy. Colposcopic findings correlated significantly with histopathologic findings (p<0.0001). Forty-four percent of patients tested positive for HPV DNA: 40 patients with high risk HPV, three patients with low risk HPV, and one patient with both high risk and low risk HPV. Sixteen of 39 patients (41%) with LGSIL on pap smear tested positive for high risk HPV; 37% of patients in this group required cervical conization because cervical biopsies demonstrated moderate/severe dysplasia. The diagnosis of moderate/severe dysplasia significantly correlated with the presence of high risk HPV [OR 78.9 (8.31-389.30)]. There was no significant correlation between the HPV DNA signal strengths and the histologic grade of dysplasia. The sensitivity and the positive predictive value of pap smear alone in identifying moderate/severe dysplasia was 62% and 96%, respectively. The combination of HGSIL pap smears and high risk HPV increased the sensitivity but not the positive predictive value for the detection of moderate/severe dysplasia to 77.7% and 95%, respectively (P=NS). CONCLUSIONS: Although in this setting, the use of hybrid capture DNA testing did not significantly improve the sensitivity or positive predictive value of the diagnosis of HGSIL cytology when compared to cytologically indicated plus colposcopically directed cervical biopsies in this population of women at high risk for the presence of disease, the combination of HGSIL pap smears and high-risk HPV did result in a clinically important increase in the diagnosis of moderate/severe dysplasia.

Diisopropylfluorophosphate binding proteins (serine hydrolases) from normal and leukemic hematopoietic cells.

Normal and leukemic hematopoietic cell lysates were labeled with [3H]-diisopropylfluorosorophosphate ([3H]-DFP), an active site inhibitor of serine hydrolases. The labeled proteins in the lysates were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by counting of gel segments for radioactivity. The results indicate the presence of distinct [3H]-DFP binding patterns for different normal and leukemic hematopoietic cells; significantly lower labeling in normal or leukemic lymphoid cells compared to myeloid or monocytoid cells; lower labeling in acute myeloblastic leukemia (FAB-M1) as compared to acute myelomonocytic leukemia (FAB-M4), chronic myelomonocytic leukemia or monocytes and an increase in [3H]-DFP binding with cell maturation along granulocytic series. Thus, these patterns could be useful in discriminating acute lymphoblastic leukemia from myeloid/monocytoid types of leukemia and for following maturation of myeloid cells, and perhaps for studying functional or maturation defects in hematopoietic cells in other pathological conditions.

High terminal deoxynucleotidyl transferase activity in pediatric patients with acute lymphocytic and acute myelocytic leukemias.

Specificity of TdT5 as a marker for ALL was evaluated by determining its activity in cells from normal control subjects and from 35 pediatric patients with ALL, AML, Hodgkin's disease and disseminated Burkitt's lymphoma. We evaluated the DNA polymerase activity, cell surface phenotypes (E rosettes, EAC rosettes, Smlg and la-like, HTLA and cALL antigens), and hematological and cytochemical characteristics in both the normal and patient groups. DNA polymerase alpha + beta and DNA polymerase gamma activity were indiscriminately high in all immature cells as found in ALL, AML, Burkitt's lymphoma and phytohemagglutinin-stimulated normal lymphocytes, when compared to mature leukocytes found in normal individuals or in patients whose cancer was in remission. High TdT activity was found in 24 of 26 T and non-T/non-B ALL patients in active phase as well as in two of three AML patients one of whom had Auer rods. Thus, TdT, although valuable for monitoring ALL patients, may have limitations in separating AML from ALL.

Inhibition of deoxynucleotide-polymerizing enzyme activities of human leukemia lymphoblasts and simian sarcoma virus by tilorone and thirteen of its analogs.

Tilorone, which is 2,7-bis[2-(diethylamino)ethoxy]-9H-fluoren-9-one dihydrochloride, and 13 of its analogs inhibited human cellular DNA polymerases alpha and beta assayed with activated DNA as template and also cellular DNA polymerase gamma and DNA polymerase from simian sarcoma virus assayed with poly(A) (dT)12-18 as template. Terminal deoxynucleotidyltransferase (TdT), which has no template requirement, was not inhibited by any of the 14 compounds when d(A)12-18 or d(G)12-18 was used as initiator. Three compounds did not inhibit TdT assayed with activated DNA as initiator, but 11 compounds did, and these 11 compounds were generally less inhibitory to TdT than to the other DNA polymerases. The three compounds that did not inhibit TdT assayed with activated DNA but did inhibit the other DNA polymerases will be useful in the characterization of TdT activity. Modifications of the polycyclic ring structure of tilorone and the kinds of substituent groups attached to the ring structures influenced the degree of inhibition of all enzymes.

Terminal deoxynucleotidyl transferase activity and cell surface antigens of two unique cell lines (NALM-1 and BALM-2) of human leukemic origin.

Two unique cell lines, NALM-1 and BALM-2 derived from lymphoblast-like cells of chronic myelogenous leukemia and rare B cell acute lymphoblastic leukemia patients, respectively, were compared with fresh parent cells from the patients and with a Philadelphia chromosome positive K-562 cell line previously established from a chronic myelogenous leukemia patient in blastic phase. NALM-1 resembled the parent cells in the presence of Philadelphia chromosome, non-T/non-B acute lymphoblastic leukemia specific antigens and lack of T or B cell markers, whereas BALB-2, like the parent cells, had two chromosome markers and bore kappa, delta and mu immunoglobulins. NALM-1 lacked Epstein-Barr virus genome, whereas BALM-2 showed the presence of Epstein-Barr virus genome. K-562 cells lacked all the antigen markers examined. All cells had high DNA polymerase alpha activity and low DNA polymerase gamma activity. NALM-1, like the parent cells and unlike K-562 cells, had high terminal deoxynucleotidyl transferase activity of about 200 mu/mg DNA, whereas BALM-2, like its parent cells, had terminal deoxynucleotidyl transferase activity of 1-2 mu/mg DNA (1 u = 1 nmole Mn++-dGTP/h on dA12-18 initiator). Terminal deoxynucleotidyl transferase was characterized by its chromatographic and sedimentation behavior, thermal sensitivity and specific inhibition by streptolydigin and terminal deoxynucleotidyl transferase antisera. These results indicate that NALM-1 and K-562 may represent different phenotypes of cells in CML blastic crisis. Moreover, NALM-1 and BALM-2 seem to have retained the characteristics of original leukemic cells from which they may have been derived.

High terminal deoxynucleotidyl transferase activity in acute myelogenous leukemia.

Although leukocytes from all 13 acute lymphoblastic leukemia patients examined had high terminal deoxynucleotidyl transferase (terminal transferase) activity (20 to 100 units/mg of cellular DNA, where 1 unit equals 1 nmole of nucleotide polymerized in 1 hr) and those from 21 acute myelocytic leukemia patients had low terminal transferase activity (0.2 to 2 units/mg of cellular DNA), the bone marrow and peripheral blood leukocytes from 2 patients with acute myelocytic leukemia, diagnosed on the basis of clinical features and the morphology, cytochemistry, and cytogenetics of the leukemic cells, had terminal transferase activity (39 to 52 units/mg of cellular DNA) equivalent to that found in leukemic lymphoblasts. These results bring under question the specificity of high terminal transferase activity outside of the thymus as a marker for leukemic lymphoblasts and, secondarily, the derivation of acute lymphoblastic leukemia cells in all cases from thymocytes. Perhaps malignant transformation in a pleuripotent stem cell with derepression of the genome for terminal transferase could account for high terminal transferase activity observed in certain leukemic cells.

Terminal deoxynucleotidyl transferase and human leukemia.

Terminal deoxynucleotidyl transferase activity is as much as several hundred fold greater in acute leukemic lymphoblasts than in unstimulated or phytohemagglutinin stimulated normal lymphocytes, and in leukocytes from other leukemias or from acute lymphoblastic leukemia patients in remission. On the other hand, acute leukemic lymphoblasts and myeloblasts as well as phytohemagglutinin stimulated normal lymphocytes have DNA polymerase activity an order of magnitude higher than that in unstimulated normal lymphocytes, and in leukocytes from chronic leukemias or from acute lymphoblastic leukemia patients in remission. Terminal deoxynucleotidyl transferase thus appears to be a useful index for the detection of leukemic lymphoblasts.