The road ahead for cervical cancer prevention and control.

Since the early 1950s, Papanicolaou ("Pap") cytology screening has dramatically reduced cervical cancer mortality in most high-income settings. Currently, human papillomavirus (hpv) vaccination has the greatest potential to reduce the global burden of cervical cancer and precancerous lesions. However, as the prevalence of precancerous lesions declines, maintaining cytology as the primary screening test in settings with established programs might become less efficient. A reduction in test performance (sensitivity, specificity, and positive predictive value) would lead to an increase in unnecessary colposcopy referrals. Fortunately, hpv dna testing has emerged as a suitable candidate to replace cytology. Compared with the Pap test, hpv testing is less specific but much more sensitive in detecting high-grade precancerous lesions, less prone to human error, and more reproducible across settings. Linkage of hpv vaccination and screening registries could serve the added role of monitoring vaccine efficacy. As a triage test, cytology is expected to perform with sufficient accuracy because most hpv-positive smears would contain relevant abnormalities. This approach and others-for example, hpv testing followed by genotyping-are being evaluated in large population studies and have already been recommended in some settings. Other specific biomarkers that might perform well for screening and triage include hpv E6/E7 messenger rna testing, methylation of host or viral genes, and p16(INK4a) staining. Considering the rapid pace of major discoveries and the anticipated arrival of a nonavalent hpv vaccine (currently in phase iii trials), the evidence base in this field has become an elusive target and will continue to be an obstacle for policymakers.

Mir-55 inhibition can reduce cell proliferation and induce apoptosis in Jurkat (Acute T cell Leukemia) cell line.

BACKGROUND: MicroRNAs are small and non-coding RNA molecules with approximately 22 nt in length that cause inhibition of translation or degradation of mRNA. MiR-155 is a kind of molecule with different functions, such as its role in proliferation, apoptosis, inflammation, differentiation, and immunity. One of its best known functions is apoptosis that affects on caspase-3 activity. The main aim of this study was evaluation of miR-155 inhibition effect on cell proliferation and apoptosis induction in Jurkat cells. MATERIAL AND METHODS: In this study, Jurkat cells along with MTT assay were used for evaluation of sensitivity to varied concentrations of miR-155 inhibitor (25, 50 and 75 nmol). MiR-155 expression level was analyzed using the quantitative real-time polymerase chain reaction (QRT-PCR). Caspase-3 activity was measured by caspase-3 colorimetric activity assay kit. Unpaired t-test was applied for the analysis of MTT and apoptosis results. Probability of 5% was assumed as statistically significant. RESULTS: According to our results, the use of miR-155 inhibitor increased the activity of caspase-3 by 2 fold in 75 nmol concentration. In this research, we found that the proper increase of miR-155 inhibitor concentration can inhibit miR-155 and consequently increase caspase-3 activity and induce apoptosis in the Jurkat cells leading to cell death ultimately. CONCLUSIONS: Apoptosis induction by miRNAs activation or inhibition is probably one of the best and low risk ways of cell death induction in malignancies. Due to role of miR-155 in several cancer cells, it may be used as a therapeutic target in future.

Effect of thyroid dysfunctions on blood cell count and red blood cell indice.

BACKGROUND: Thyroid hormones have a crucial role in metabolism and proliferation of blood cells. Thyroid dysfunction induces different effects on blood cells such as anemia, erythrocytosis leukopenia, thrombocytopenia, and in rare cases causes' pancytopenia. It also alter RBC indices include MCV, MCH, MCHC and RDW. Thus this study attempted to evaluate effect of hypo & hyperthyroidism on blood cell count and RBC indices. MATERIALS AND METHODS: This study performed on 102 patients with hypothyroid (14.1 years), 84 with hyperthyroid (15.6 years) and 118 healthy individuals (15.2 years) as control group. Initially patients TSH level of patients was determined by ELISA method, and then according to TSH ranges (0.3-5.5µIU/mL) patients were divided into two Hyperthyroidism (TSH<0.3µIU/mL) and hypothyroidism (TSH>5.5µIU/mL) groups. Then, complete blood count was measured by cell counter. Finally, obtained results were analyzed by SPSS software. RESULTS: Analyzes of obtained data revealed statistically significant difference between two groups of patients in RBC count, MCH, MCHC, RDW, HB and HCT(P-value<0.05), but the difference was not significant for WBC and PLT counts and MCV (P-value>0.05). CONCLUSION: In case of patients with unknown hematological dysfunctions, must be evaluated for thyroid hormones.

Rosai-Dorfman disease following bone marrow transplantation for pre-B cell acute lymphoblastic leukemia.

A child with acute pre-B cell lymphoblastic leukemia underwent haploidentical bone marrow transplantation (BMT) after first relapse. Approximately 8 months after the BMT, he developed a soft tissue mass overlying a defect in the left frontal bone. He was found to have several additional osteolytic lesions but no evidence of lymphadenopathy or organomegaly. A biopsy of the presenting lesion demonstrated a polymorphous infiltrate composed predominantly of S-100 protein and CD68 immunoreactive histiocytic cells. Together with the presence of emperipolesis, the process was interpreted as Rosai-Dorfman (R-D) disease. He received chemotherapy with vinblastine, prednisone, 6-mercaptopurine and methotrexate and has been in remission for over 4 years. Only one previous example of acute lymphoblastic leukemia in childhood has been reported with R-D disease.

Cytogenetic and molecular characterization of a congenital mesoblastic nephroma.

A newborn baby boy was diagnosed with the mixed form of congenital mesoblastic nephroma (CMN) representing both classic and cellular histology features in the renal tumor. Additionally, the patient had skin and bone lesions consistent with multifocal involvement of a generalized infantile fibromatosis (IFS). Both skin and bone lesions were distinctly different from CMN and did not represent metastasis. The primary tumor cell line (MCH-MN-1), established from the resected right kidney tumor, had a diploid DNA content. Cytogenetic studies revealed deletion on the long arm of chromosome 3 (q21q24) and duplication on the short arm of chromosome 11 (p15). MCH-MN-1 cells expressed ETV6-NTRK3 gene fusion transcripts, characteristic of cellular and mixed forms of CMNs. The cells had high p21 and low Bax mRNA expression in the reverse transcriptase-polymerase chain reaction (RT-PCR) assay. The high level of proliferative marker (Ki67) mRNA expression correlated well with the pluripotent nature of MCH-MN-1 in tissue culture (cell doubling time = 12.4 h). Our results showed that MCH-MN-1 might be a good model cell line for investigations on mesoblastic nephroma.

Preponderance of thiopurine S-methyltransferase deficiency and heterozygosity among patients intolerant to mercaptopurine or azathioprine.

PURPOSE: To assess thiopurine S-methyltransferase (TPMT) phenotype and genotype in patients who were intolerant to treatment with mercaptopurine (MP) or azathioprine (AZA), and to evaluate their clinical management. PATIENTS AND METHODS: TPMT phenotype and thiopurine metabolism were assessed in all patients referred between 1994 and 1999 for evaluation of excessive toxicity while receiving MP or AZA. TPMT activity was measured by radiochemical analysis, TPMT genotype was determined by mutation-specific polymerase chain reaction restriction fragment length polymorphism analyses for the TPMT*2, *3A, *3B, and *3C alleles, and thiopurine metabolites were measured by high-performance liquid chromatography. RESULTS: Of 23 patients evaluated, six had TPMT deficiency (activity < 5 U/mL of packed RBCs [pRBCs]; homozygous mutant), nine had intermediate TPMT activity (5 to 13 U/mL of pRBCs; heterozygotes), and eight had high TPMT activity (> 13.5 U/mL of pRBCs; homozygous wildtype). The 65.2% frequency of TPMT-deficient and heterozygous individuals among these toxic patients is significantly greater than the expected 10% frequency in the general population (P <.001, chi(2)). TPMT phenotype and genotype were concordant in all TPMT-deficient and all homozygous-wildtype patients, whereas five patients with heterozygous phenotypes did not have a TPMT mutation detected. Before thiopurine dosage adjustments, TPMT-deficient patients experienced more frequent hospitalization, more platelet transfusions, and more missed doses of chemotherapy. Hematologic toxicity occurred in more than 90% of patients, whereas hepatotoxicity occurred in six patients (26%). Both patients who presented with only hepatic toxicity had a homozygous-wildtype TPMT phenotype. After adjustment of thiopurine dosages, the TPMT-deficient and heterozygous patients tolerated therapy without acute toxicity. CONCLUSION: There is a significant (> six-fold) overrepresentation of TPMT deficiency or heterozygosity among patients developing dose-limiting hematopoietic toxicity from therapy containing thiopurines. However, with appropriate dosage adjustments, TPMT-deficient and heterozygous patients can be treated with thiopurines, without acute dose-limiting toxicity.

Expression of apoptosis, cell proliferation, and drug resistance genes in pediatric Wilms' tumors.

The expression of genes associated with apoptosis, cell proliferation and drug resistance in tumor cells was investigated in two pediatric Wilms' tumor patients (MCH-WT-1 and MCH-WT-3) for their association with cell cycle, daunorubicin accumulation and clinical data. DNA content, cell cycle and drug accumulation were analyzed immediately after surgery by flow cytometry and mRNA expression by reverse transcriptase-polymerase chain reaction (RT-PCR) assay. Primary cell cultures were established from tumor specimens and tumor cells in both cases showed epithelial morphology. Although cell proliferation markers (Ki67 and PCNA) were expressed in both cases, MCH-WT-3 showed higher levels of mRNA expression, which corresponded, with metastatic behavior of the tumor in the patient. While p53 and p21 mRNAs were expressed at low levels in MCH-WT1, MCH-WT-3 showed high levels of p21 mRNA only. The increased expression of cyclin kinase inhibitor (p21) in MCH-WT-3 compared to MCH-WT-1 correlated with a higher percentage of G0/G1 cell population in the tumor specimen. Despite the expression of multidrug resistance markers (MDR1 and LRP) in MCH-WT-1, flow cytometric analysis showed tumor cell populations with very low and high daunorubicin accumulation and with the absence of any effect for verapamil and dipyridamole on daunorubicin accumulation of tumor cells.

Developmental regulation of Zbu1, a DNA-binding member of the SWI2/SNF2 family.

The SWI2/SNF2 gene family has been implicated in a wide variety of processes, involving regulation of DNA structure and chromatin configuration, mitotic chromosome segregation, and DNA repair. Here we report the characterization of the Zbu1 gene, also known as HIP116, located on human chromosome band 3q25, which encodes a DNA-binding member of this superfamily. Zbu1 was isolated in this study by its affinity for a site in the myosin light chain 1/3 enhancer. The protein has single-stranded DNA-dependent ATPase activity, includes seven helicase motifs, and a RING finger motif that is shared exclusively by the RAD5, spRAD8, and RAD16 family members. During mouse embryogenesis, Zbu1 transcripts are detected relatively late in fetal development and increase in neonatal stages, whereas the protein accumulates asynchronously in heart, skeletal muscle, and brain. In adult human tissues, alternatively spliced Zbu1 transcripts are ubiquitous with highest expression in these tissues. Gene expression is also dramatically induced in human tumor lines and in Li-Fraumeni fibroblast cultures, suggesting that it is aberrantly regulated in malignant cells. The developmental profile of Zbu1 gene expression and the association of the protein with a tissue-specific transcriptional regulatory element distinguish it from other members of the SWI2/SNF2 family and suggest novel roles for the Zbu1 gene product.

Chromosomal localization and cDNA cloning of the human DBP and TEF genes.

We have isolated cDNA and genomic clones and determined the human chromosome positions of two genes encoding transcription factors expressed in the liver and the pituitary gland: albumin D-site-binding protein (DBP) and thyrotroph embryonic factor (TEF). Both proteins have been identified as members of the PAR (proline and acidic amino acid-rich) subfamily of bZIP transcription factors in the rat, but human homologues have not been characterized. Using a fluorescence in situ hybridization technique, the DBP locus was assigned to chromosome 19q13, and TEF to chromosome 22q13. Each assignment was confirmed by means of human chromosome segregation in somatic cell hybrids. Coding sequences of DBP and TEF, extending beyond the bZIP domain to the PAR region, were highly conserved in both human-human and interspecies comparisons. Conservation of the exon-intron boundaries of each bZIP domain encoding exon suggested derivation from a common ancestral gene. DBP and TEF mRNAs were expressed in all tissues and cell lines examined, including brain, lung, liver, spleen, and kidney. Knowledge of the human chromosome locations of these PAR proteins will facilitate studies to assess their involvement in carcinogenesis and other fundamental biological processes.

Outcome of moderate aplastic anemia in children.

PURPOSE: In order to assist in the management of newly diagnosed children with moderate aplastic anemia (MAA) we reviewed the clinical course and outcome of children with MAA seen at our institution over the past 12 years and compared them with children with severe aplastic anemia (SAA). PATIENTS AND METHODS: MAA was defined as having a hypocellular bone marrow and cytopenia in at least two cell lines not in the severe range. Twelve children met these criteria. Twenty-eight children with SAA were seen during the same interval. Patients with MAA were treated with immunomodulation with antithymocyte globulin and/or cyclosporine if they progressed to SAA. RESULTS: Five patients with MAA progressed to SAA at a median interval of 18 months from diagnosis. The other seven patients required no therapy or only received transfusions for < or = 6 months after diagnosis. The survival of the patients with MAA was significantly better than that of patients with SAA treated with immunomodulation (p = 0.022). All patients with MAA are alive at a median follow up of 7 years and are transfusion independent; only one patient currently receives therapy. Residual hematologic abnormalities in children with MAA included thrombocytopenia, leukopenia, and macrocytosis. CONCLUSIONS: In this small series of children with MAA the outcome was excellent and significantly better than in patients with SAA; more than half recovered with minimal or no therapy. Patients who progressed to SAA responded well to treatment. A larger prospective study is needed to conclusively define the natural history of MAA.

Quality of survival among children treated for brain stem glioma.

In order to describe the status of long-term survivors of brain stem glioma, neuropsychological and behavioral measures were obtained a median of 2.5 (range 1.5-5.6) years after diagnosis from 16 survivors of 51 consecutively diagnosed children with brain stem glioma between 1983 and 1991. Among 11 children with dorsally exophytic tumors, 7 were treated with surgery alone (SRG) and 4 received conventionally fractionated local cranial radiation therapy (CFRT; 54-56 Gy) to the brain stem following surgery, 3 of these because of recurrent disease. Five others with diffusely infiltrative brain stem tumors received hyperfractionated radiation therapy (HFRT; 70.2 Gy) to the brain stem; 4 following biopsy or limited resection and 1 without prior surgery. IQs of children in the CFRT (mean 89, SD 24.4) and HFRT (mean 85, SD 12.7) groups were not significantly different. Children in the SRG group had significantly higher IQs (mean 100, SD 11.0) and fewer neurologic deficits than those who had received CFRT or HFRT. However, after statistically controlling for severity of neurologic deficits, treatment had no effect on IQ. The severity of residual neurologic deficits accounted for 42% of the variance in IQ scores; children with fewer neurologic problems scored higher. Additional studies are required to evaluate the potential neuropsychological benefits of equivalent total doses of HFRT compared to CFRT.

Predominance of pilocytic histology in dorsally exophytic brain stem tumors.

We report the magnetic resonance imaging (MRI) and clinico-histologic characterization of dorsally exophytic brain stem gliomas (DEBSGs). Between 1983 and 1991, 12 of 51 patients evaluated for the diagnosis of brain stem glioma were found to have DEBSGs emanating from the pons, pontomedullary junction or medulla. Eleven of the 12 patients had classic juvenile pilocytic astrocytomas. Unlike most other brain stem tumors, these patients were young (median 38 months, range 17-75), had a relatively long duration of symptoms (median 7 months, range 2-24) and displayed signs of increased intracranial pressure with limited cranial nerve paresis, absence of pyramidal tract findings, and near normal brain stem auditory-evoked potentials. MRI characteristically showed sharply demarcated lesions with decreased signal intensity on T1, and increased intensity on T2 sequences. Except for cystic areas, these tumors showed bright, uniform enhancement after gadolinium-DTPA. In all patients, 50-100% of the tumor volume could be resected. Three of 10 patients who received no immediate postoperative treatment eventually demonstrated disease progression, and 2 patients with subtotal resections who were treated with radiation and/or chemotherapy postoperatively remain disease-free for extended periods of time. The only death occurred in the 1 patient treated with chemotherapy who died of secondary leukemia. The overall and progression-free survival of these patients at 2 years is 100 and 67% as compared to 18 and 21%, respectively, for other concomitantly treated nonexophytic brain stem gliomas.2+ the ability to achieve significant degrees of resection.

Coamplification of the CDK4 gene with MDM2 and GLI in human sarcomas.

The 34-kilodalton cyclin-dependent kinase, p34cdk4, is a major catalytic subunit of mammalian D-type cyclins, which act during the G1 phase of the cell cycle to enforce the decision of cells to enter S phase. A murine complementary DNA clone was used to clone the cognate human CDK4 gene, which was localized to human chromosome 12, band q13, by fluorescence in situ hybridization. Because this chromosomal band contains the GLI and MDM2 genes, which are frequently amplified in human sarcomas, we analyzed CDK4 copy number and expression in a panel of sarcoma cell lines. An osteosarcoma cell line, OsACL, manifested a 25-fold increased copy number of CDK4, amplified concordantly with both GLI and MDM2, whereas a rhabdomyosarcoma cell line, SJRH30, was found to have an amplicon that included CDK4 and GLI but not MDM2. CDK4 mRNA and protein were overexpressed in both cell lines, and nucleotide sequencing analysis indicated that the gene had not sustained mutations. These observations provide the first evidence for amplification of a gene encoding a cell division cycle protein kinase, complement recent data indicating that genes encoding D-type cyclins are targets of chromosomal rearrangement and gene amplification in tumor cells, and suggest that CDK4 amplification might contribute to oncogenesis.

Acquired progressive lymphangioma.

Acquired progressive lymphangioma is rare and can histologically mimic well-differentiated angioendothelioma. In a 9-year-old boy with acquired progressive lymphangioma, we demonstrated that the neoplasm consists of at least a vascular component and a smooth muscle component. The presence of type IV collagen around many vascular channels suggests that an intermediate stage of differentiation between blood vessels and lymphatics may be present. Our findings indicate that acquired progressive lymphangioma is most likely a complex hamartoma composed of vascular channels and smooth muscle.

The antimicrobial effect of various endodontic sealers.

The antimicrobial activity of an endodontic sealer can be helpful in destroying any remaining root canal microbes. Therefore it was decided to test the antimicrobial activity of several commonly used endodontic sealers. The sealers used were Grossman's sealer, Tubliseal, Calciobiotic, Sealapex, Hypocal, eucapercha, Nogenol, and AH26. Also tested were dry calcium hydroxide powder, calcium hydroxide mixed with saline, and a Teflon formulation. The microbes used were Streptococcus mutans (a gram-positive microaerophile). Staphylococcus aureus (a gram-positive facultative anaerobe), and Bacteroides endodontalis (a gram-negative obligate anaerobe). The freshly mixed sealers were placed into the prepared wells of agar plates inoculated with the test microorganisms. After varying periods of incubation, the zones of inhibition of bacterial growth were observed and measured. Grossman's sealer had the greatest overall antibacterial activity. However, AH26 had the greatest activity against B. endodontalis. The zinc oxide-eugenol-based sealers had more antimicrobial activity than either the calcium hydroxide-based sealers or eucapercha.