Direct Conversion of Human Endothelial Cells Into Liver Cancer-Forming Cells Using Nonintegrative Episomal Vectors

Liver cancer is an aggressive cancer associated with a poor prognosis. Development of therapeutic strategies for liver cancer requires fundamental research using suitable experimental models. Recent progress in direct reprogramming technology has enabled the generation of many types of cells that are difficult to obtain and provide a cellular resource in experimental models of human diseases. In this study, we aimed to establish a simple one-step method for inducing cells that can form malignant human liver tumors directly from healthy endothelial cells using nonintegrating episomal vectors. To screen for factors capable of inducing liver cancer-forming cells (LCCs), we selected nine genes and one short hairpin RNA that suppresses tumor protein p53 (TP53) expression and introduced them into human umbilical vein endothelial cells (HUVECs), using episomal vectors. To identify the essential factors, we examined the effect of changing the amounts and withdrawing individual factors. We then analyzed the proliferation, gene and protein expression, morphologic and chromosomal abnormality, transcriptome, and tumor formation ability of the induced cells. We found that a set of six factors, forkhead box A3 (FOXA3), hepatocyte nuclear factor homeobox 1A (HNF1A), HNF1B, lin-28 homolog B (LIN28B), MYCL proto-oncogene, bHLH transcription factor (L-MYC), and Kruppel-like factor 5 (KLF5), induced direct conversion of HUVECs into LCCs. The gene expression profile of these induced LCCs (iLCCs) was similar to that of human liver cancer cells, and these cells effectively formed tumors that resembled human combined hepatocellular-cholangiocarcinoma following transplantation into immunodeficient mice. Conclusion: We succeeded in the direct induction of iLCCs from HUVECs by using nonintegrating episomal vectors. iLCCs generated from patients with cancer and healthy volunteers will be useful for further advancements in cancer research and for developing methods for the diagnosis, treatment, and prognosis of liver cancer.

Analysis of extracellular vesicles as a potential index for monitoring differentiation of neural lineage cells from induced pluripotent stem cells

To improve cell production efficacy, it is important to evaluate cell conditions during culture. Extracellular vesicles (EVs) secreted from various cells are involved in stem cell differentiation. As EVs carry information about their source cells, we hypothesized that they may serve as a noninvasive index of cell conditions. We evaluated changes in EV morphology, concentration, and microRNA (miRNA) and protein expression in culture supernatants during the differentiation of induced pluripotent stem cells (iPSCs) into neural lineage cells, for application in regenerative medicine for Parkinson's disease. We observed EVs (50-150 nm) in culture supernatants of iPSCs and differentiated cells. The EVs expressed the exosome markers CD63, CD81, and CD9. Throughout differentiation, the EV concentration in the supernatants decreased, and EV miRNA and protein expression changed substantially. Especially, miR-106b, involved in neural stem cell differentiation and normal brain development, was considerably downregulated. CD63 expression correlated with the CORIN-positive cell rate, which is an index of differentiation. Thus, EV concentration and miRNA and protein expression may reflect the differentiation status of iPSCs. These findings pave the way for the development of novel and sensitive cell culture monitoring methods.

Direct reprogramming of human umbilical vein- and peripheral blood-derived endothelial cells into hepatic progenitor cells

Recent advances have enabled the direct induction of human tissue-specific stem and progenitor cells from differentiated somatic cells. However, it is not known whether human hepatic progenitor cells (hHepPCs) can be generated from other cell types by direct lineage reprogramming with defined transcription factors. Here, we show that a set of three transcription factors, FOXA3, HNF1A, and HNF6, can induce human umbilical vein endothelial cells to directly acquire the properties of hHepPCs. These induced hHepPCs (hiHepPCs) propagate in long-term monolayer culture and differentiate into functional hepatocytes and cholangiocytes by forming cell aggregates and cystic epithelial spheroids, respectively, under three-dimensional culture conditions. After transplantation, hiHepPC-derived hepatocytes and cholangiocytes reconstitute damaged liver tissues and support hepatic function. The defined transcription factors also induce hiHepPCs from endothelial cells circulating in adult human peripheral blood. These expandable and bipotential hiHepPCs may be useful in the study and treatment of human liver diseases.

The conditions to induce human hepatic progenitor cells from other cell types are unclear. Here, the authors reprogram human endothelial cells to hepatic progenitor cells by expressing FOXA3, HNF1A and HNF6, capable of giving rise to hepatocytes and cholangiocytes that reconstitute damaged liver tissues on transplantation.

The Dynamics of Transcriptional Activation by Hepatic Reprogramming Factors

Specific combinations of two transcription factors (Hnf4α plus Foxa1, Foxa2, or Foxa3) can induce direct conversion of mouse fibroblasts into hepatocyte-like cells. However, the molecular mechanisms underlying hepatic reprogramming are largely unknown. Here, we show that the Foxa protein family members and Hnf4α sequentially and cooperatively bind to chromatin to activate liver-specific gene expression. Although all Foxa proteins bind to and open regions of closed chromatin as pioneer factors, Foxa3 has the unique potential of transferring from the distal to proximal regions of the transcription start site of target genes, binding RNA polymerase II, and co-traversing target genes. These distinctive characteristics of Foxa3 are essential for inducing the hepatic fate in fibroblasts. Similar functional coupling of transcription factors to RNA polymerase II may occur in other contexts whereby transcriptional activation can induce cell differentiation.

Kupffer cells induce Notch-mediated hepatocyte conversion in a common mouse model of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is a malignant epithelial neoplasm composed of cells resembling cholangiocytes that line the intrahepatic bile ducts in portal areas of the hepatic lobule. Although ICC has been defined as a tumor arising from cholangiocyte transformation, recent evidence from genetic lineage-tracing experiments has indicated that hepatocytes can be a cellular origin of ICC by directly changing their fate to that of biliary lineage cells. Notch signaling has been identified as an essential factor for hepatocyte conversion into biliary lineage cells at the onset of ICC. However, the mechanisms underlying Notch signal activation in hepatocytes remain unclear. Here, using a mouse model of ICC, we found that hepatic macrophages called Kupffer cells transiently congregate around the central veins in the liver and express the Notch ligand Jagged-1 coincident with Notch activation in pericentral hepatocytes. Depletion of Kupffer cells prevents the Notch-mediated cell-fate conversion of hepatocytes to biliary lineage cells, inducing hepatocyte apoptosis and increasing mortality in mice. These findings will be useful for uncovering the pathogenic mechanism of ICC and developing prevenient and therapeutic strategies for this refractory disease.

Intrahepatic cholangiocarcinoma can arise from Notch-mediated conversion of hepatocytes

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary malignancy in the liver. ICC has been classified as a malignant tumor arising from cholangiocytes; however, the co-occurrence of ICC and viral hepatitis suggests that ICC originates in hepatocytes. In order to determine the cellular origin of ICC, we used a mouse model of ICC in which hepatocytes and cholangiocytes were labeled with heritable, cell type–specific reporters. Our studies reveal that ICC is generated by biliary lineage cells derived from hepatocytes, rather than cholangiocytes. Additionally, we found that Notch activation is critical for hepatocyte conversion into biliary lineage cells during the onset of ICC and its subsequent malignancy and progression. These findings will help to elucidate the pathogenic mechanism of ICC and to develop therapeutic strategies for this refractory disease.

Flow cytometric isolation and clonal identification of self-renewing bipotent hepatic progenitor cells in adult mouse liver

The adult liver progenitor cells appear in response to several types of pathological liver injury, especially when hepatocyte replication is blocked. These cells are histologically identified as cells that express cholangiocyte markers and proliferate in the portal area of the hepatic lobule. Although these cells play an important role in liver regeneration, the precise characterization that determines these cells as self-renewing bipotent primitive hepatic cells remains to be shown. Here we attempted to isolate cells that express a cholangiocyte marker from the adult mouse liver and perform single cell-based analysis to examine precisely bilineage differentiation potential and self-renewing capability of these cells. Based on the results of microarray analysis and immunohistochemistry, we used an antibody against CD133 and isolate CD133(+) cells via flow cytometry. We then cultured and propagated isolated cells in a single cell culture condition and examined their potential for proliferation and differentiation in vitro and in vivo. Isolated cells that could form large colonies (LCs) in culture gave rise to both hepatocytes and cholangiocytes as descendants, while maintaining undifferentiated cells by self-renewing cell divisions. The clonogenic progeny of an LC-forming cell is capable of reconstituting hepatic tissues in vivo by differentiating into fully functional hepatocytes. Moreover, the deletion of p53 in isolated LC-forming cells resulted in the formation of tumors with some characteristics of hepatocellular carcinoma and cholangiocarcinoma upon subcutaneous injection into immunodeficient mutant mice. These data provide evidence for the stem cell-like capacity of isolated and clonally cultured CD133(+) LC-forming cells.

CONCLUSION

Our method for prospectively isolating hepatic progenitor cells from the adult mouse liver will facilitate study of their roles in liver regeneration and carcinogenesis.

Tbx3 controls the fate of hepatic progenitor cells in liver development by suppressing p19ARF expression

Although the T-box family of transcription factors function in many different tissues, their role in liver development is unknown. Here we show that Tbx3, the T-box gene that is mutated in human ulnar-mammary syndrome, is specifically expressed in multipotent hepatic progenitor cells, ;hepatoblasts', isolated from the developing mouse liver. Tbx3-deficient hepatoblasts presented severe defects in proliferation as well as uncontrollable hepatobiliary lineage segregation, including the promotion of cholangiocyte (biliary epithelial cell) differentiation, which thereby caused abnormal liver development. Deletion of Tbx3 resulted in the increased expression of the tumor suppressor p19(ARF) (Cdkn2a), which in turn induced a growth arrest in hepatoblasts and activated a program of cholangiocyte differentiation. Thus, Tbx3 plays a crucial role in controlling hepatoblast proliferation and cell-fate determination by suppressing p19(ARF) expression and thereby promoting liver organogenesis.

Insulin-like growth factor 2 (IGF2) and IGF2 receptor gene variants are associated with fetal growth

AIM

Normal variation in size at birth is a result of the interaction between fetal genetic factors and the maternal uterine environment. It is, however, unclear how genetic factors contribute to fetal growth. The insulin-like growth factor (IGF) system regulates uterine, placental and fetal development, thereby partially controlling the rate of fetal growth. The aim of this study was to investigate the associations between the neonatal birth weight and the genotypes of polymorphic loci in the IGF2 and IGF2 receptor (IGF2R) genes.

METHODS

We determined the genotypes of two polymorphic loci in the IGF2 gene and four loci in the IGF2R gene in 884 pairs of normal Japanese mothers and their neonates, and compared the genotypes with the birth weight converted into standard deviation scores (SDSs) according to sex, parity and gestational weeks at delivery.

RESULTS

There was a significant difference in birth weight SDSs among the three neonatal +3123/ApaI genotypes of the IGF2 gene; AA, AG and GG. There was also a significant difference in birth weight among the three neonatal c.901C > G genotypes of the IGF2R gene; CC, CG and GG.

CONCLUSION

These findings indicate that both IGF2 and IGF2R gene variants are associated with fetal growth.

ABCA5 resides in lysosomes, and ABCA5 knockout mice develop lysosomal disease-like symptoms

ABCA5 is a member of the ABC transporter A subfamily, and a mouse orthologue (mABCA5) in newborn mouse brain and neural cells was identified by reverse transcription-PCR. Full-length cDNA cloning revealed that mABCA5 consists of 1,642 amino acid residues and that its putative structure is that of a full-type ABC transporter having two sets of six transmembrane segments and a nucleotide binding domain. Immunohistochemical studies revealed that mABCA5 is expressed in brain, lung, heart, and thyroid gland. A subcellular localization analysis showed that mABCA5 is a resident of lysosomes and late endosomes. Abca5(-)(/)(-) mice exhibited symptoms similar to those of several lysosomal diseases in heart, although no prominent abnormalities were found in brain or lung. They developed a dilated cardiomyopathy-like heart after reaching adulthood and died due to depression of the cardiovascular system. In addition, Abca5(-)(/)(-) mice also exhibited exophthalmos and collapse of the thyroid gland. Therefore, ABCA5 is a protein related to a lysosomal disease and plays important roles, especially in cardiomyocytes and follicular cells.

Analysis of aptamer binding site for HCV-NS3 protease by alanine scanning mutagenesis

Nonstructural protein 3 (NS3) of Hepatitis C virus (HCV) is a multifunctional protein and possesses protease, nucleotide triphosphatase and helicase activities. The N-terminal domain of NS3 (amino acids 1027-1218; delta NS3) has a trypsin-like protease activity and is essential for processing of viral polyprotein. Accordingly it is a potential target for anti-HCV drugs and we isolated RNA aptamers (Kd = 10 nM, Ki = 100 nM) using in vitro selection strategy. To study the interaction between delta NS3 and its aptamer, we applied alanine scanning mutagenesis and constructed seven mutant proteins at positive amino acid residues on the surface of delta NS3. Binding and inhibitory activities of the NS3 aptamer against mutant proteins were kinetically analyzed. These results clarified that especially Arg161 and Arg130 are important for interaction with the NS3 aptamer.

Analysis of interaction between RNA aptamer and protein using nucleotide analogs

Non-structural protein 3 (NS3) derived from Hepatitis C virus (HCV) is essential for viral proliferation and has two functional domains; trypsin-like serine protease and helicase. Recently we obtained three types of RNA aptamers (G9-I, -II and -III) bound to NS3 protease domain (delta NS3) by in vitro selection and confirmed their strong inhibition for protease activity. These aptamers have a common sequence, 5'-GA(A/U)UGGGAC-3', forming a loop structure by Mulfold secondary structure modeling. G9-I shows a three-way junction and G9-II and -III have four-way junction structures. To characterize the active structure of these aptamers, we applied modification interference analysis using nucleotide analogs and identified common important nucleotides in these three aptamers.

Construction of the dual-functional RNA ligand against HCV NS3 protease and helicase

Non-structural protein 3 (NS3) of hepatitis C virus (HCV) contains two distinct activities, protease and helicase which are essential for the HCV replication. In the previous study, we succeeded to obtain RNA aptamers, G9-I, G9-II and G9-III specific for the NS3 protease domain (delta NS3) by in vitro selection (1). As the result of mutational analysis in G9-I, we could obtain the minimum length of RNA structure, delta NEO-III maintaining the full inhibitional activity as shown in G9-I. Furthermore, we created a bi-functional novel RNA ligand, NEO-III-14U which was constructed by connecting delta NEO-III with (U)14 at the 3' terminal. NEO-III-14U was able to inhibit the unwinding of duplex DNA catalyzed by the Full-NS3 helicase activity as well as the protease activity in vitro. Consequently, we could obtain the dual-functional RNA ligand which could inhibit both NS3 protease and helicase activities essential for the HCV proliferation.

Cyclization of aryl acyl radicals generated from S-(4-cyano)phenyl thiolesters by a nickel complex catalyzed electroreduction

Aromatic acyl radicals generated from S-(4-cyano)phenyl 2-alkenylthiobenzoate by a nickel complex catalyzed electroreduction undergo 5- and 6-exo cyclization to give 1-indanone and dihydro-1-naphthalenone derivatives, respectively.

Impact of maintenance chemotherapy on disease-free survival in patients with stage Ic and II epithelial ovarian cancer

PURPOSE OF INVESTIGATION

To evaluate the impact on disease free survival (DFS) with maintenance chemotherapy following complete surgery and adjuvant chemotherapy in patients with stage Ic and II epithelial ovarian cancer by a retrospective study.

METHODS

One hundred and forty patients with stage Ic and stage II epithelial ovarian cancer were classified into three groups according to the modality of maintenance chemotherapy (no therapy, oral or intravenous administration of anti-cancer drugs). DFS was compared among the three groups, and independent predictive factors for relapse were analyzed.

RESULTS

There were no statistically significant differences in DFS among the three groups for either stage Ic or II cancers, stage Ic and stage II. Multivariate analysis revealed that independent predictive factors for relapse were stage II (p = 0.004) in all patients and less than three cycles of adjuvant chemotherapy in stage II patients (p = 0.015).

CONCLUSION

Maintenance chemotherapy had no impact on DFS in patients with stage Ic or II epithelial ovarian cancer.

Hypermutable change of human UV(r)-1 cells by p53 overexpression

The p53 protein has been reported to regulate cellular responses to genetic stress such as far-ultraviolet light (UV), protecting human cells from mutation. Levels of p53 protein in hypermutable RSa cells were found here to increase soon after UV irradiation, while those in UV(r)-1 cells, a hypomutable variant of RSa cells, showed a delayed increase. Three cell lines overexpressing wild-type p53 in UV(r)-1 cells exhibited higher sensitivity to UV mutagenicity than did control U-V-7 cells transfected with vector alone, assessed using the ouabain-resistance phenotypic mutation test and identification of K-ras codon 12 base substitution mutation. On the other hand, U-V-7 cells showed UV-induced elevation of antipain-sensitive protease activity, but p53 transfectants did not. Moreover, antipain treatment to U-V-7 cells was increased susceptibility to UV mutagenicity. Thus, p53 protein overproduction may sensitize human cells, at least those tested, to UV mutagenicity, in association with inhibition of protease activity.

Magnetic resonance imaging in the evaluation of vaginal foreign bodies in a young girl

A 7-year-old girl with foul-smelling, bloody vaginal discharge for more than 2 years was initially suspected of suffering from vaginal foreign bodies. Although plain radiography revealed no abnormal findings in the pelvis, magnetic resonance imaging (MRI) showed multiple low intensity objects and an intact vaginal wall. Four plastic toys were removed with forceps under general anesthesia. MRI is supposed to be the best technique for evaluating vaginal foreign bodies in young girls.

Analysis of E6 variants of human papillomavirus type 33, 52 and 58 in Japanese women with cervical intraepithelial neoplasia/cervical cancer in relation to their oncogenic potential

The variation of the E6 region of human papillomavirus type 16 (HPV16) is associated with a high risk for cervical carcinogenesis. To see whether the same is the case with HPV33, 52 and 58, known to have high homology with HPV16, we analyzed the E6 sequence variation of these HPVs in 107 Japanese women with cervical intraepithelial neoplasia (CIN) or invasive cervical cancer (ICC): 20 HPV33-positive, 46 HPV52-positive and 41 HPV58-positive cases. HPV33 variants were more frequently observed in CINs I/II than in CIN III/ICCs (71% (5/7) versus 15% (2/13), P=0.02). In HPV52-positive cases, a single E6 variant was detected in 98% of the cases, whereas the prototype accounted for 98% of HPV58-positive cases. In summary, the distribution of E6 variants is different among HPV types tested, suggesting a link between E6 variation and oncogenic potential being type-specific.

[Studies of anti-cytomegalovirus IgG antibody positive rate and cytomegalovirus mononucleosis in adults]

We analyzed anti-Cytomegalovirus (CMV) IgG and IgM antibody (EIA) and anti-Epstein-Barr virus (EBV) viral capsid antigen (VCA) IgG and IgM antibody (FA) in adults during 1994-1999. We examined these IgM sero-positive patient's medical records, and diagnosed CMV mononucleosis and EBV mononucleosis. Anti-CMV antibody positive rates decreased from 87.6% in 1994 to 77.8% in 1999. Especially in twenties, anti-CMV antibody positive rates decreased from 65.2% in 1994 to 53.3% in 1999. On the other hand, anti-EBV VCA antibody positive rates were not changed (91-94%). Number of cases of CMV mononucleosis increased from 2 cases in 1994 to 16 cases in 1999, but EBV mononucleosis was not changed. These results suggested that increasing cases of CMV mononucleosis was influenced by decreasing anti-CMV antibody positive rate.

Increased and decreased expression of CD69 and CD23, respectively, in gravity-stressed lymphocytes

BACKGROUND

Recent studies have shown that gravity-changing stress modulates expression levels of cell surface molecules on human lymphocytes. However, previous in vitro microgravity studies have been performed with lymphocytes treated with mitogenic agents.

HYPOTHESIS

The aim of the study was to test if exposure of cells to gravity-changing stress alone alters the expression levels of cell surface molecules. Specifically, we examined whether the expression of activation markers is altered after exposure of lymphocytes to combinations of microgravity and hypergravity.

METHODS

We used free-fall in parabolic flight for human subjects and a drop-shaft to expose peripheral blood mononuclear cells (PBMC) to gravity-changing stress. After such exposure, PBMC were isolated, and expression levels of CD69, CD23 and CD38 were estimated using three-color flow cytometry.

RESULTS

Increased percentages of CD69-positive cells were observed with PBMC from 3 of 4 volunteers who undertook 10 parabolic flights. Exposure of blood to gravity-changing stress in the drop-shaft increased both ratios of CD69-positive cells and levels of CD69 expression on T and B cells. In contrast, the percentages of CD23-positive B cells was decreased. However, gravity-changing stress was not always followed by significant alteration in CD38 expression.

CONCLUSIONS

Our findings suggest that CD69 and CD23 might be useful markers that are up- and down-regulated, respectively, after exposure of lymphocytes to gravity-changing stress.

Subsequent pregnancy outcome in patients with spontaneous resolution of HCG after evacuation of hydatidiform mole: comparison between complete and partial mole

This study compared subsequent pregnancy outcome in patients with complete and partial hydatidiform moles. Among 1052 patients with molar pregnancy (complete mole, 801; partial mole, 251) monitored at Chiba University Hospital between 1981 and 1999, 891 patients (84.7%) had spontaneous resolution of human chorionic gonadotrophin (HCG) after mole evacuation, and 161 patients (15.3%) required chemotherapy. Of the 891 patients, 438 (49.2%) had 650 subsequent pregnancies. The pregnancy outcome was not significantly different in patients with complete and partial moles, and was comparable with that in the general Japanese population. The incidence of repeat molar pregnancy in patients with complete and partial mole (1.3 and 1.5% respectively) was 5-fold higher than that of the general population, while no increased risk of persistent gestational trophoblastic tumour (GTT) associated with later molar pregnancy was observed. During HCG follow-up, 10 patients (1.1%) developed secondary high-risk GTT between 14 and 54 months after mole evacuation. The incidence of high-risk GTT in patients with and without subsequent pregnancies was 0.46% (2/438) and 1.8% (8/453) respectively (P = 0.1243). In conclusion, patients with complete and partial mole can anticipate a normal future reproductive outcome, and pregnancies after experiencing hydatidiform mole may not affect the development of high-risk GTT.

Significance of perivascular lymphocytic infiltrates in endometrial carcinoma

BACKGROUND

The objective of this study was to clarify the significance of perivascular lymphocytic infiltrates (PLI) in endometrial carcinoma.

METHODS

The pathologic records of 127 patients with endometrioid type adenocarcinoma confined to the uterus were reviewed retrospectively. The patients were divided into 4 groups based on the presence or absence of vascular invasion (VI) and PLI: VI-PLI- (n = 87), VI-PLI+ (n = 7), VI+PLI+ (n = 22), and VI+PLI- (n = 11). Pathologic features including tumor grade, myometrial invasion, cervical involvement, vascular invasion-associated changes (VIAC; VI and/or PLI), tumor size, ovarian metastasis, and pelvic lymph node metastasis were assessed statistically.

RESULTS

Selective pelvic lymphadenectomy was performed in 108 patients, and metastasis was identified in 6 cases (5.6%). Lymph node metastasis was the only independent variable related to recurrence (Cox regression analysis, P = 0.0008). Perivascular lymphocytic infiltrates correlated closely with VI (Fisher exact test, P < 0.0001). Vascular invasion-associated changes was the best predictor of lymph node metastasis (logistic regression analysis, P = 0.039), but among the three categories of VIAC, only the VI+PLI- group was significantly associated with lymph node metastasis (P = 0.0045). The odds ratios of VI+PLI- and VI+PLI+ cases for lymph node metastasis were 64.54 and 3.24, respectively.

CONCLUSIONS

Although VIAC is the best predictor of lymph node metastasis, the presence of PLI is associated with a lower risk of lymph node metastasis among VIAC groups.

Detection of fetal HPCs in maternal circulation after delivery

BACKGROUND

Circulation of mature fetal blood cells in the maternal blood for a certain postpartum period has been verified, but detailed study of the fetal HPCs has not been reported. The objective of this study was to evaluate the frequency and clearance of these cells in the peripheral blood of puerperal women.

STUDY DESIGN AND METHODS

PBMNCs from 15 puerperal women who gave birth to male infants were cultured in semi-solid medium containing hematopoietic stimulating factors. Colonies formed in the medium were individually characterized, collected, and subjected to PCR amplification of the SRY gene on Y chromosome to confirm fetal origin.

RESULTS

The mean numbers of fetal progenitor cell colonies isolated per mL of maternal blood were 1.63, 2.48, 0.56, 0.12, and 0 on the day of delivery, at 4 days, 1 month, 6 months, and 1 year after delivery, respectively. There was no difference in the ratio of fetal versus maternal colonies between erythroid and granulocyte/macrophage lineages.

CONCLUSION

The present study demonstrated that a significant number of fetal HPCs circulate in the maternal blood for a duration of at least 6 months after delivery.

Detection of human papillomaviruses in cervical neoplasias using multiple sets of generic polymerase chain reaction primers

OBJECTIVE

The aim of this study was to evaluate precisely the differences in the spectra of human papillomavirus (HPV) types detected by different generic primer pairs commonly used for detection of this extraordinarily heterogeneous virus.

METHODS

Three sets of polymerase chain reaction (PCR) primers for the L1 open reading frame (ORF) and two sets for E6/E7 ORFs were used to detect HPVs in DNAs from 107 cervical tissues, including 77 cervical neoplasias. HPV types were determined by analysis of restriction fragment length polymorphisms (RFLPs) and nucleotide sequencing.

RESULTS

A high overall detection rate of HPV in cervical neoplasias (76/77, 98.7%) was achieved by polymerase chain reaction (PCR) amplification with multiple sets of generic primers, while the detection rate for each individual primer pair varied from 48/77 (62%) to 70/77 (91%). Only in 34 of 77 cases (44%) were HPV DNAs positive for all sets of primer pairs. Further determination of HPV types by RFLPs and nucleotide sequencing showed inconsistencies between the PCR primer pairs used.

CONCLUSION

Our study revealed that the HPV detection rate is critically affected by the choice of PCR primers, and that appropriate use of combinations of generic PCR primer sets followed by RFLP analyses is both necessary and sufficient for typing most HPVs in cervical lesions. More precise methods such as sequencing would be necessary in only a few cases.

Adjuvant hysterectomy in low-risk gestational trophoblastic disease

OBJECTIVE

To evaluate the efficacy of adjuvant hysterectomy with chemotherapy for women with low-risk gestational trophoblastic disease.

METHODS

One hundred fifteen consecutive Japanese women (16-52 years old) with low-risk gestational trophoblastic disease (46 with metastatic disease and 69 without) were treated initially with single-agent chemotherapy (etoposide in 85, methotrexate in 27, and actinomycin D in three) with or without adjuvant hysterectomy, and 97 patients (84.3%) achieved primary remission with those treatments. Eight women (9.4%) treated with etoposide required other regimens because of drug resistance or toxicities. The total dose of etoposide given to achieve primary remission was analyzed in 77 women who received etoposide alone or with adjuvant hysterectomy.

RESULTS

In 34 women with metastatic disease, the mean (+/- standard deviation [SD]) total dose of etoposide was not significantly different with and without adjuvant hysterectomy (2857 +/- 842 mg versus 2815 +/- 815 mg; P =.957; Mann-Whitney U test). However, in 43 women without metastases, the total dose of etoposide was significantly less in those who had adjuvant hysterectomies than in those who did not (1750 +/- 635 mg versus 2545 +/- 938 mg; P <.05; Mann-Whitney U test).

CONCLUSION

Adjuvant hysterectomy decreased the total dose of etoposide given to achieve primary remission in women with nonmetastatic, low-risk gestational trophoblastic disease. If the lesions of gestational trophoblastic disease are confined to the uterus and the woman has no desire to preserve fertility, she should be informed of adjuvant hysterectomy as a treatment option.

Diagnostic accuracy of intraoperative imprint cytology in ovarian epithelial tumors

OBJECTIVE

To evaluate imprint cytology (IC) as the intraoperative pathological consultations for ovarian epithelial tumors (OET).

METHOD

We reviewed ICs obtained from 354 consecutive surgical specimens of OET. Cytological specimens were classified into five categories. Final pathological diagnoses were made according to the WHO classification. We performed logistic regression analysis, calculated the limits among benign, borderline, and malignant lesions, and analyzed the diagnostic accuracy. We also made receiver operating characteristic (ROC) curves regarding IC.

RESULTS

The accuracies to differentiate benign and malignant lesions were 87.1 and 83.6%, respectively. In contrast, that of borderline lesions was 30.0%. The areas under ROC curves to diagnose benign, and malignant lesions were 0.888 (P<0.05) and 0.951 (P<0.05), respectively, that meant IC was significantly useful for diagnosis of malignancy.

CONCLUSIONS

IC applied to OET was proved to be practically useful in establishing an intraoperative diagnosis by ROC curves.

The RNA aptamer-binding site of hepatitis C virus NS3 protease

Nonstructural protein 3 (NS3) of hepatitis C virus (HCV) is a trypsin-like protease and is essential for processing of viral polyprotein. Accordingly, it is a potential target for anti-HCV drugs. Recently we could isolate RNA aptamers (G9-I, II, and III) which bind and inhibit NS3 protease using in vitro selection strategy. In addition, G9-I aptamer showed noncompetitive inhibition. In order to elucidate the binding site of G9-I aptamer in NS3 protease domain (deltaNS3), we carried out alanine scanning mutagenesis at positive charged residues on the surface of deltaNS3. The result of binding analysis by surface plasmon resonance measurements and protease inhibition assay clarified that Arg161 as well as Arg130 of deltaNS3 are essential for interaction with G9-I aptamer. This region appears to be a potential targeting site for anti-HCV drugs.

2',5'-oligoadenylate synthetase gene in chicken: gene structure, distribution of alleles and their expression

We have cloned the gene for chicken 2',5'-oligoadenylate synthetase (ChOAS) by the method of polymerase chain reaction with use of ChOAS cDNA sequence. The ChOAS gene is composed of five introns and six exons containing all of the sequence of the ChOAS cDNA from the start to the stop codon. The first five exons of ChOAS gene which encode the OAS catalytic domain have a similar structure to HuOAS1 gene including the exon-intron boundaries. However, the length of introns of ChOAS gene is only 1/7 of those of HuOAS1 gene. The sixth exon of the ChOAS gene encodes the ubiquitin-like (UbL) domain of two consecutive sequence (UbL1 and UbL2) homologous to ubiquitin. ChOAS encoded in a single copy gene has at least two alleles, OAS(*)A and OAS(*)B. The differences between these two alleles are in the sixth exon of the gene; a 96-nucleotide sequence in the UbL1 portion of OAS(*)A is deleted from OAS(*)B. No OAS(*)B gene was detected in nine lines of chickens tested other than Leghorns. Almost the same levels of ChOAS-A and -B proteins induced physiologically in erythrocytes were detected in infant chickens (2-week-old), but in grown-up chickens (6-month-old) the level of erythrocyte OAS-B was markedly reduced in most of B/B chickens. Thus, the UbL domain of ChOAS is responsible for the maintenance of the OAS level in the tissue.

Loop electrosurgical excision procedure (LEEP) during first trimester of pregnancy

Loop electrosurgical excision procedure (LEEP) during pregnancy can be performed safely as in non-pregnant women and can replace traditional cone biopsy when performed in the first trimester.

[Evaluation of adverse effects including neurotoxicity of combination chemotherapy with paclitaxel and carboplatin]

The adverse effects of combination chemotherapy with paclitaxel and carboplatin, including neurotoxicity, arthralgia and muscle pain, were evaluated in 21 patients (30 courses) using questionnaires of the Gynecologic Oncology Chemotherapy Joint Research Group. The scores of pain and numbness peaked from the third to fourth day of treatment. Although the pain score improved subsequently, the numbness score persisted at a high level. Compared to the first and second courses, the peak pain score was higher and persisted for a longer duration in the fifth and sixth courses. Using the questionnaires, we were able to recognize a high incidence of numbness and pain in patients on combination chemotherapy with paclitaxel and carboplatin, and identify the degree and temporal changes of the adverse effects. Our results suggest that the questionnaires used in this study are clinically useful for evaluating the degree and clinical course of pain and numbness in anticancer chemotherapy.

Detection of epithelial ovarian-cancer-associated antigens involved in immune complexes by monoclonal antibodies

To detect antigenic molecules involved in immune complexes (ICs) in patients with epithelial ovarian cancer, we developed several monoclonal antibodies (Mabs) by hybridoma technology from mice immunized with ovarian cancer tissues. Hybridoma supernatants were differentially screened with a panel of ICs purified from ascites of patients with ovarian cancer and with ICs from pooled normal human sera by the enzyme-linked immunosorbent assay (ELISA). From about 6,000 supernatants screened in 6 fusions, 4 Mabs showing preferential binding to the ascitic ICs were selected. Their antibody specificity was further examined with serum-free conditioned media of various cancer cell lines by an ELISA inhibition assay. The reactivity of 3 Mabs was inhibited by the media of epithelial ovarian cancer cell lines, but not by any of the non-ovarian cell lines tested, suggesting that the target antigens were derived from ovarian cancer cells. Furthermore, ICs detected by one Mab, designated 2F11, were elevated in the sera from 18 of 42 (42.9%) patients with epithelial ovarian cancer, but not in those from 39 patients with benign ovarian tumors or from 29 healthy individuals (with the exception of 1 serum), using sandwich ELISA with protein A as the capture reagent.

Comparison of chemotherapies with methotrexate, VP-16 and actinomycin-D in low-risk gestational trophoblastic disease. Remission rates and drug toxicities

OBJECTIVE

To compare the efficiency and toxicity of four chemotherapeutic regimens in low-risk gestational trophoblastic disease.

METHODS

Since 1974, 247 patients with low-risk gestational trophoblastic disease have been treated with 5-day intramuscular methotrexate (MTX) (conventional MTX), 5-day intravenous drip infusion of VP-16, 5-day intravenous actinomycin-D (Act-D) or 8-day alternating intramuscular MTX-folic acid (MTX-CF) at Chiba University School of Medicine. We compared the primary remission rate, the response of human chorionic gonadotropin and the prevalence of drug toxicities in these 4 regimens.

RESULTS

The primary remission rate was 73.6% in the conventional MTX regimen, 90.1% in VP-16, 84.0% in Act-D, and 60.0% in MTX-CF. The primary remission rate was significantly higher in the VP-16 and Act-D regimens than in the conventional MTX and MTX-CF regimens. The response rate was significantly higher in the VP-16 regimen than in the other 3 regimens. The drug toxicity with VP-16 and Act-D was less than that with conventional MTX and MTX-CF regimens.

CONCLUSIONS

The VP-16 regimen was highly effective and less toxic for gestational trophoblastic disease compared with other chemotherapeutic regimens.

[Comparison between cytomegalovirus hepatitis and Epstein-Barr virus hepatitis in healthy adults]

In order to determine the factors responsible for the differentiation of cytomegalovirus (CMV) hepatitis and Epstein-Barr virus (EBV) hepatitis in previously healthy adults, the clinical features and laboratory data of both types of hepatitis were retrospectively analyzed. CMV hepatitis showed a tendency to increase in our department. In comparison with EBV hepatitis, CMV hepatitis occurred in significantly older hosts than EBV hepatitis. We found that lymphadenopathy, cough and sore throat was more common in EBV hepatitis than in CMV hepatitis. The number of peripheral white blood cell count and atypical lymphocytes, and serum GOT, GPT, LDH and CRP levels of CMV and EBV hepatitis showed no significant differences.

Enhanced oncogenicity of human papillomavirus type 16 (HPV16) variants in Japanese population

To investigate whether HPV16 E6 variants carry an elevated risk for cervical cancer in Japanese population, we investigated the E6 sequence variation in 40 cervical intraepithelial neoplasias (CINs) I-III and 43 invasive cervical cancers (ICCs), all positive for HPV16. HPV16 E6 variants were frequently found in ICCs than in CINs (88 vs. 65%, P=0.01). The E6 D25E, a rare variant in Western countries, was most frequently observed in ICC (44%). CIN I/II lesions with HPV16 variants were less likely to regress than those with HPV16 prototype (P=0.048). The finding that HPV16 E6 variants represent a significant risk factor is common between Western and Japanese women despite the different distribution of each variant.

Combination chemotherapy with methotrexate, etoposide, and actinomycin D for high-risk gestational trophoblastic tumors

OBJECTIVES

The goal of this study was to evaluate the efficacy, toxicity, and survival of patients with high-risk gestational trophoblastic tumors (GTTs) treated with a methotrexate-etoposide-actinomycin D (MEA) regimen without cyclosphosphamide or vincristine.

METHODS

Thirty-nine consecutive patients with high-risk GTTs (28 were defined high risk by WHO criteria) were treated with primarily the MEA regimen. Among them, 27 patients had received no prior chemotherapy and 12 had received prior chemotherapy. Survival, causes of treatment failure, and toxicity were analyzed retrospectively.

RESULTS

After treatment with the MEA regimen, 29 of 39 patients achieved primary remission (74.4%), 8 developed resistance (20.5%), and 2 died of widespread metastases and chemotherapy-related toxicity. All 8 patients who developed resistance were treated with high-dose 5-fluorouracil and actinomycin D (FA); 6 were salvaged and 2 died of refractory disease. Three patients relapsed; 2 were controlled with FA or cisplatin-based chemotherapy and 1 who refused further treatment died. The disease-free survival rate was 87%. WHO grade 4 leukocytopenia and thrombocytopenia with the MEA regimen occurred in 5.3 and 6.4%, respectively, of the cycles; other toxic effects were acceptable and manageable.

CONCLUSIONS

At present, MEA chemotherapy (without cyclophosphamide or vincristine) is our treatment of choice for patients with high-risk GTT. Its toxicity is predictable and manageable. For patients who become resistant to MEA, new salvage chemotherapy regimens are needed.

Isolation and characterization of RNA aptamers specific for the hepatitis C virus nonstructural protein 3 protease

Nonstructural protein 3 (NS3) from hepatitis C virus (HCV) is a serine protease that provides an essential function in maturation of the virus by cleaving the nonstructural regions of the viral polyprotein. The goal of this work was to isolate RNA aptamers that bind specifically to the NS3 protease active site in the truncated polypeptide DeltaNS3. RNA aptamers were selected in vitro by systematic evolution of ligands by exponential enrichment (SELEX). The RNA pool for SELEX had a 30-nucleotide randomized core region. After nine selection cycles, a pool of DeltaNS3-specific RNA aptamers were obtained. This RNA pool included 45 clones that divided into three main classes (G9-I, II and III). These classes include the conserved sequence GA(A/U)UGGGAC. These aptamers bind to DeltaNS3 with a binding constant of about 10 nM and inhibit approximately 90% of the protease activity of DeltaNS3 and MBP-NS3 (full-length of NS3 fused with maltose binding protein). In addition, these aptamers inhibited approximately 70% of the MBP-NS3 protease activity in the presence of the NS4A peptide P41. G9-I aptamer appeared to be a noncompetitive inhibitor for DeltaNS3 with a Ki approximately 100 nM in the presence of P41. These results suggest that the pool of selected aptamers have potential as anti-HCV compounds. Mutational analysis of the G9-I aptamer demonstrated that the sequences required for protease inhibition are in stem I, stem III and loop III of the aptamer. These regions include the conserved sequence GA(A/U)UGGGAC.

Human papillomavirus-positive well-differentiated villoglandular adenocarcinoma of the uterine cervix: A case report and review of the literature

OBJECTIVE

A case of well-differentiated villoglandular adenocarcinoma of the uterine cervix, which was positive for human papillomavirus type 18, was reported.

METHODS

The patient was a 52-year-old multipara who was referred to our department because of an abnormal Papanicolaou smear. A 4.0-cm exophytic lesion involving the cervix was detected. She was staged as FIGO IIa and radical hysterectomy combined with bilateral pelvic lymphadenectomy was performed. In addition to histopathological examination of the resected tumor, immunohistochemical studies of estrogen and progesterone receptors were performed using monoclonal antibodies. Detection of human papillomavirus DNA was attempted by polymerase chain reaction using consensus primers.

RESULTS

The tumor was a typical well-differentiated villoglandular adenocarcinoma involving the vaginal wall. Both estrogen and progesterone receptors were negative. Human papillomavirus type 18 DNA was detected in the resected tumor.

CONCLUSION

'This is the first report of a case of typical well-differentiated villoglandular adenocarcinoma which was positive for human papillomavirus.

Prognostic factors in young women with endometrial carcinoma: a report of 20 cases and review of literature

We retrospectively reviewed the pathologic features of patients with endometrial carcinoma (EC) treated in our facility between 1989 and 1998. First, we identified the clincopathologic features of young women with EC and compared them with similar patients from the literature. Second, 148 EC patients were divided into two groups: group A (age</=45 years, n = 20) and B (age>45, n = 128). The mean follow-up periods were 65 months and 50 months in groups A and B, respectively. Group A patients had better disease-free survival (Kaplan-Meier method, P = 0.0283) compared to group B patients. The independent variables related to disease-free survival (Cox regression analysis) were age (P = 0.0001), stage (P = 0.0183), histology (P = 0.0011), and lymph node metastasis (P = 0.0007). The distribution of stage was significantly different between the two groups (Chi-square test, P = 0.0089). More group A patients (18 of 20; 90%) had early stage disease. There were no significant differences (Fisher's exact test) between the two groups in histology, grade, cervical involvement, vascular invasion, tumor size, ovarian malignancy, and lymph node metastasis. However, group A patients had a significant higher incidence of disease confined to the inner half of the myometrium than group B patients (P = 0.0004). We statistically confirmed that young women with EC had better outcome due to a significantly higher proportion of early stage disease and less myometrial invasion than older patients.

Prenatal findings in Brachmann-de Lange syndrome

We present a case of Brachmann-de Lange syndrome, in which prenatal ultrasonographic evaluation demonstrated increased nuchal translucency, early onset of intrauterine growth retardation, and limb abnormalities in the first, second, and third trimester, respectively.

RGS domain in the amino-terminus of G protein-coupled receptor kinase 2 inhibits Gq-mediated signaling

We have previously shown that not only G protein-coupled receptor kinase (GRK) 2, but also a catalytically inactive Lys220Trp GRK2 decreases endothelin (ET)-1-induced inositol 1,4,5-trisphosphate (IP3) formation, and demonstrated the presence of phosphorylation-independent desensitization mechanism. To clarify the role of GRK2 other than that as a kinase, we characterized an RGS (regulator of G protein signaling)-like domain in the amino-terminus of GRK2. Both GRK2(1-181) and GRK2(54-174) suppressed Ca2+ responses induced by angiotensin II (Ang II) and ET-1, and bound directly with Galphaq but not Galphas nor Galphai3 in the presence of GDP and AlF4-. These results demonstrate that GRK2 regulates Gq-mediated signaling negatively by direct interaction between its RGS domain and the transitional state of Galphaq, as well as through phosphorylation of activated receptors by its kinase domain.

Hydatidiform mole coexistent with a twin live fetus: a national collaborative study in Japan

A national collaborative study was conducted in Japan to evaluate the clinical course and the sequelae of patients with hydatidiform mole coexistent with twin live fetus (HMTF). Seventy-two cases of HMTF were diagnosed based on gross appearance and histopathological criteria. In 18 cases, the molar parts were cytogenetically confirmed to be of androgenetic origin (complete mole). The overall incidence of persistent trophoblastic tumour (PTT) in patients with HMTF was 30.6%, and it increased to 50.0% in the 18 patients with proven androgenetic complete mole coexistent with twin live fetus (CHMTF). Among these patients, the mean gestational age at termination of pregnancy or delivery in those who developed PTT (n = 9) and those who did not (n = 9) were 20.6 and 19.4 weeks respectively. The incidence of severe maternal complications was significantly higher in patients who subsequently developed PTT (P < 0.05). The rate of subsequent development of PTT in patients with CHMTF was found to be considerably higher than in a previous study of patients with single complete mole (50 and 12.5% respectively). However, since the risk of malignancy is unchanged with advancement of gestational age, continued pregnancy may be allowed in patients with HMTF provided that severe maternal complications are controlled and fetal karyotype and development are normal.