BACKGROUND: Topoisomerase II (TOPO II) is an enzyme that separates intertwined chromosomes during DNA synthesis by transiently breaking and joining DNA strands. The level of TOP II is one of the determinants of cellular sensitivity to anti-tumor drugs in non-Hodgkin's lymphoma patients. The alpha form of TOPO II has been recently used as a marker of cellular proliferation. High levels of TOPO IIalpha are expressed in aggressive and proliferative tumors. METHODS: This study was designed to evaluate the relationship between TOPO IIalpha expression and clinicopathological parameters including age, gender, the serum LDH level, the serum beta2-microglobulin level and stage, or expressions, of Ki-67, p53 and p27, in non-Hodgkin's lymphoma. We analyzed forty-one biopsied tissue specimens from patients with non-Hodgkin's lymphoma. RESULTS: The expression of TOPO IIalpha increased with the clinical stage and it was correlated with Ki-67 and p53 expressions. However, TOPO IIalpha expression did not have any significant correlation with age, gender, the serum LDH level, the serum 2-microglobulin level and the p27 expression. CONCLUSIONS: TOPO IIalpha expression is a useful marker of cellular proliferation and it may serve as a prognostic factor of a tumor's progression and aggressiveness in non-Hodgkin's lymphomas.
Cell Proliferation ; DNA Topoisomerases, Type I* ; DNA Topoisomerases, Type II ; DNA* ; Humans ; Ki-67 Antigen ; Lymphoma, Non-Hodgkin*

PURPOSE: E2F-1 is a transcriptor that converts G1 to S in the cell cycle, and Topoisomerase II-alpha is a key enzyme in the metabolism of DNA, and an indicator of cell replication. The purpose of this study was to evaluate the clinical validity of E2F-1 and Topoisomerase II-alpha as prognostic factors in colorectal cancer. METHODS: The expressions of E2F-1 and Topoisomerase II-alpha were studied immunohistochemically using tumor specimen sections fixed with formalin and paraffin-embedded for 84 cases of colorectal cancer. The correlation between E2F-1 and Topoisomerase II-alpha expressions, and their relationship with the clinicopathological factors, such as tumor differentiation, tumor invasion, lymph node metastasis and tumor stage were investigated. RESULTS: Of the 84 specimens, 43 (51.2%) were immunohistochemically negative for E2F-1, and 41 (48.8%) were positive. The expression of E2F-1 correlated with poor tumor differentiation, increased lymph node metastasis and high tumor stage. The expression of Topoisomerase II-alpha also correlated with poor tumor differentiation, increased lymph node metastasis and high tumor stage. The E2F-1 and Topoisomerase II-alpha expressions indices were significantly correlated. CONCLUSION: These results suggest that the expressions of E2F-1 and DNA Topoisomerase II-alpha may play a role as a prognostic factor for colorectal cancer, but further studies will be required for its comfirmation.
Cell Cycle ; Colorectal Neoplasms* ; DNA ; DNA Topoisomerases, Type I* ; Formaldehyde ; Lymph Nodes ; Metabolism ; Neoplasm Metastasis

OBJECTIVE: The relationship was studied between expression of c-erbB-2 oncoprotein and topoisomerase II-alpha as proliferating marker in precancerous lesions and invasive squamous carcinomas of the uterine cervix. METHODS: Total 81 formalin-fixed, paraffin-embedded sections of low-grade intrasquamous lesion (22 cases), high-grade intraepithelial lesions (42 cases) and invasive squamous cell carcinomas (17 cases) in the uterine cervix were stained by immunohistochemistry for expression of the c-erbB-2 oncoprotein and topoisomerase II-alpha. RESULTS: The expression of c-erbB-2 oncoprotein and staining index (mean+/-S.D) of topoisomerase II-alpha were statistically significant between precancerous lesions and invasive carcinoma. The expression of c-erbB-2 oncoprotein has correlation with staining index (mean+/-S.D) of topoisomerase II-alpha. CONCLUSION: There results suggest that the expression of c-erbB-2 protein has relationship with progression of squamous lesions and topoisomerase II-alpha is an useful proliferating marker in the uterine cervix. And, the expression of c-erbB-2 protein has correlation with expression of topoisomerase II-alpha.
Carcinoma, Squamous Cell* ; Cervix Uteri* ; DNA Topoisomerases, Type I* ; DNA* ; Female ; Immunohistochemistry ; Receptor, erbB-2

PURPOSE: To determine whether the expression of DNA topoisomerase II and P-glycoprotein are of prognostic value. MATERIALS AND METHODS: We evaluated the expression of DNA topoisomerase II and P-glycoprotein immunohistochemically in a retrospective study of samples from 44 patients with breast cancer. Thirty two among 44 patients (72.7%) received chemotherapeutic treatments (CMF or FAC protocol) and/or tamoxifen postoperatively. RESULTS: P-glycoprotein was detected in the 27 samples of 44 patients (61.3%). The expression of P-glycoprotein was increased in the patients older than 50 years, with distant metastases, and with death on follow-up. DNA topoisomerase II was detected in the 34 samples of 44 patients (77.2%). The expression of topoisomerase II was increased in the patients younger than 50 years, with recurrent tumor, with distant metastases, and with death on follow-up. The expression of P-glycoprotein and topoisomerase II was not correlated with other clinico-pathological factors including the size of primary tumor, involvement of lymph node, histologic grade, and clinical stage. The correlation between expression of P-glycoprotein and topoisomerase II was not significant. CONCLUSION: The immunohistochemical evaluation of P-glycoprotein and topoisomerase II before treatment in breast cancer has little clinical prognostic value.
Breast Neoplasms* ; Breast* ; DNA Topoisomerases, Type I* ; DNA Topoisomerases, Type II* ; DNA* ; Follow-Up Studies ; Humans ; Immunohistochemistry ; Lymph Nodes ; Neoplasm Metastasis ; P-Glycoprotein* ; Retrospective Studies ; Tamoxifen

Irinotecan (CPT-11) is a chemotherapeutic agent that inhibits topoisomerase I and has shown efficacy against advanced colorectal cancer. Diarrhea is the most common toxicity that has been reported to be as high as 87% in patients treated with irinotecan. However, the serious complications including acute hemorrhagic colitis, intestinal ulceration, and intestinal perforation may be uncommon events with irinotecan therapy. We report the first Korean case of acute hemorrhagic colitis induced by irinotecan administration in the patient with advanced colon cancer.
Colitis* ; Colonic Neoplasms ; Colorectal Neoplasms ; Diarrhea ; DNA Topoisomerases, Type I ; Humans ; Intestinal Perforation ; Ulcer

Human DNA Topoisomerase I (hTopo I) has been identified to be an efficient target of many effective antitumor drugs. Natural hTopo I is not convenient to be used in screening because of its low concentration in cells. In order to fast screen new anticancer drugs targeting at hTopo I from natural compounds in vitro, hTopo I gene open reading frame (ORF) has been successfully cloned and overexpressed in Pichia pastoris. Total RNA extracted from Hela cells was reversely transcripted to synthesize cDNA with the hTopo I specific antisense primer and the hTopo I ORF was synthesized by PCR. After digestion with EcoR I and Kpn I, the synthesized fragment was inserted into pPICZaA, gave rise to pPICZalpha-hTopoI. After digestion with Sac I, the lined pPICZalpha-hTopoI was transformed into Pichia pastoris strains (KM71, X33 and SMD1168) by electroporation and integrated into their genome. After screened on YPDS plates (containing 1000 ug/mL zeocin), the high-copy recombinant strains (KM-hTopoI, X33-hTopoI and SMD-hTopol) could overexpress recombinant hTopo I, which was fused to the alpha-factor secretion signal and could be secreted into the supernatant in the culture. alpha-factor could be cleaved from the expressed protein during secretion. A higher activity amount of the enzyme was secreted by the particular strain SMD-hTopoI because of its absence of proteimase A than by other strains which possess proteinase A activity. After optimizing the fermentation conditions, a relatively higher enzyme activity in the culture supernatant could be obtained when SMD-hTopoI was induced in BMMY (pH7.25) at 20 degrees C , with addition of 0.5% (V/V) methanol and 3% (V/V) nutrient liquid every 24h. The enzyme activity reached 43 000 u/mL, the yield reached 11 mg/L, achieving approximate 10% of total protein in the culture supernatant. SDS-PAGE and Western blot analyses showed that the mass of the recombinant hTopo I was 91 kD with no glycosylation.
DNA Topoisomerases, Type I ; biosynthesis ; genetics ; Fermentation ; Humans ; Pichia ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics

PURPOSE: CKD-602, a newly developed water-soluble campthotecin analogue, is a anticancer agent which act as a DNA topoisomerase I inhibitor. CKD-602 is known as more potent and tolerable agent. The main purposes of this study were to measure the cytotoxic effect of CKD-602 on the oral cancer cell lines and to evaluate the apoptotic aspect of dead cells. MATERIALS AND METHODS: To determine the cytotoxic effect of CKD-602 on the oral cancer cell lines in comparison with various cell lines, such as lung cancer and colon cancer cell lines, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was performed. And apoptosis was analyzed using fluorescence-activated cell sorting(FACS) system. RESULTS: CKD-602 decreased the viability of malignant cells in a dose dependent manner and in a time dependent manner. CKD-602 showed excellent cytotoxicity to the oral cancer cell lines. Also, apoptotic portion was increased in a dose dependent manner. CONCLUSION: These findings indicated that CKD-602 induced apoptotic cell death in the various cell lines including oral cancer cell lines. From the results, it was suggested that CKD-602 would be a potential therapeutic agent for the oral cancer. More successive researches on the anticancer effect of CKD-602 should be performed.
Apoptosis ; Camptothecin ; Cell Death ; Cell Line* ; Colonic Neoplasms ; DNA Topoisomerases, Type I ; Lung Neoplasms ; Mouth Neoplasms*

The development of drug resistance is a major obstacle in effective cancer chemotherapy. Multidrug resistance(MDR) is a widely studied phenomenon of interest to both clinicians and research workers because many different cancer chemotherapeutic agents are involved and the genetic basis of MDR is understood to a large extent. Several studies show that the P-glycoprotein (P-gp), multidrug resistance-associated protein(MRP), glutathione-s-transferase-pi(GST-pi), and DNA topoisomerase II(topo II) have a complex role for the malignant phenotypes and MDR. Clearly, there is a need to investigate links between the diverse characteristics of tumors and the emergence of drug resistance. We have therefore used reverse transcription-polymerase chain reaction(RT-PCR) assay to analyze expressions of MDR-related genes including the mdr1, MRP, topo II and GST-t gene in normal testis and testis tumors. The results are as follows: 1. The expression levels of topo II and GST-n genes in testis tumors, especially in the nonseminomatous germ cell tumor(NSGCT), were significantly higher than in normal testis(p=0.015 and 0.025, respectively). 2. The MDR-related gene expressions in testis tumors did not appear to be correlated with stage(p>0.05 in each case) and chemotherapy status(p>0.05 in each case). 3. MRP expression levels in primary tumors were much higher than in metastatic tumors. 4. In NSGCT, the coexpressions of the topo II and GST-r or MRP genes were significantly correlated but, seminoma showed no correlation between MDR-related genes in the same sample. Although the mechanism of these connection are not known, the results suggest that these expression patterns and higher GST-rexpression in NSGCF compared to seminoma confer diverse characteristics including difference in the presentation of tumor markers and the responsiveness to chemotherapy on NSGCF and seminoma.
DNA Topoisomerases, Type I ; DNA Topoisomerases, Type II ; Drug Resistance ; Drug Therapy ; Gene Expression* ; Germ Cells* ; Neoplasms, Germ Cell and Embryonal* ; P-Glycoprotein ; Phenotype ; Seminoma ; Testis* ; Biomarkers, Tumor

PURPOSE: Clinical courses of breast cancer are very different, and concern for finding a predictable marker of breast carcinomas has increased. This study focused on the relationship between the expressions of DNA topoisomerase II-alpha as a proliferative marker, and E2F-1 as a transcription factor, with clinicopathological factors of infiltrating duct carcinomas of the breast. METHODS: We investigated the expressions of E2F-1 and DNA topoisomerase II-alpha in 43 patients with infiltrating ductal carcinomas using immunohistochemical staining, and the results were analyzed with regard to clinicopathological parameters. RESULTS: Among 43 infiltrating ductal carcinomas, 24 (55.8%) were immunohistochemically negative on E2F-1 and 19 (44.2%) were positive. The expression of E2F-1 correlated with increased tumor size, positive axillary lymph node meta stasis and high stage. The topoisomerase II-alpha index correlated with increased tumor size, positive lymph node metastasis, high stage, high histological grade and negative estrogen receptor. The expression of E2F-1 and the topo II-alpha index were significantly correlated. CONCLUSION: These results suggest that the expressions of DNA topoisomerase II-alpha and E2F-1 play some role as prog nostic factors for infiltrating duct carcinomas of the breast, but much more study will be required.
Breast Neoplasms* ; Breast* ; Carcinoma, Ductal ; DNA Topoisomerases, Type I* ; DNA* ; Estrogens ; Humans ; Lymph Nodes ; Neoplasm Metastasis ; Transcription Factors

Synergistic antitumor effects of HB (berberine alpha-hydroxy-beta-decanoylethyl sulfonate, houttuyn berberine) with HCPT (hydroxycamptothecine), and its correlative mechanism were studied in vitro. MTT assay was employed to determine the cytotoxicity of HB combined with HCPT in tumor cells culture in vitro, IC50 and combination index (CI value) were used to evaluate the synergistic effects. The supercoiled DNA relaxation mediated by topoisomerase I & II was measured by agarose gel electrophoresis assay, and influence of HB was detected. The results showed that HB could inhibit the proliferation of tumor cells (SGC-7901, SW1116 and SW480) in vitro, and the inhibition ratio was increased, IC50 was reduced when combining with HCPT. CI value of the two drugs was less than 1 in HepG2, SW480, SGC-7901 and SW1116 cells. The lowest value was 0.447, 0.626, 0.161 and 0.178 in these tumor cells, respectively, further indicating HB has synergistic action with HCPT on suppressing tumor proliferation. The agarose gel electrophoresis assay showed HB can inhibit topoisomerase I & II activity of SW480 cells at the concentration of 2.0-8.0 mg x L(-1). HCPT is a typical inhibitor of topoisomerase I , the synergistic action between HCPT and HB on suppressing tumor proliferation is perhaps related to the congenerous inhibition of topoisomerase.
Antineoplastic Agents, Phytogenic ; pharmacology ; Berberine ; analogs & derivatives ; pharmacology ; Camptothecin ; analogs & derivatives ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; DNA Topoisomerases, Type I ; metabolism ; DNA Topoisomerases, Type II ; metabolism ; Drug Synergism ; Humans ; Topoisomerase I Inhibitors ; pharmacology