bluuebunny/crossref_metadata_2025 huggingface dataset:
Survival of cervix cancer patients in Harare, Zimbabwe, 1995–1997
Authors: Chokunonga Eric , Ramanakumar Agnihotram V. , Nyakabau Anna M. , Borok Margaret Z. , Chirenje Z. Michael , Sankila Risto , Parkin D. Maxwell
Published: January 2004

The survival experience of 284 patients with cancer of the cervix uteri registered by the population‐based Zimbabwe National Cancer Registry in 1995–1997 is described. The vital status of these subjects was established by linkage with death registration and by retrieval of patient files from medical records departments. Untraced patients were contacted at home. Of the 284, 177 (62.3%) were dead and 76 (26.8%) were alive at the closing date of the study (31 December 1999), with only 31 cases (10.9%) lost to follow‐up. Overall observed and relative survival at 3 years were 44.2% and 45.2%, respectively. Half of the cases (139) had been referred and treated in the radiotherapy department. Survival was significantly greater in the first 3 years for patients who received radiotherapy treatment compared to those that had not, but this difference had disappeared by the fourth year of follow‐up. Many cases presented late (distant metastasis), and extent of disease was an important determinant of survival; cases with metastases had a risk of death some 3 times that of patients with localized disease. The results demonstrate the importance of earlier diagnosis and availability of effective treatment in the African context. © 2003 Wiley‐Liss, Inc.
Resistance of pancreatic cancer to gemcitabine treatment is dependent on mitochondria‐mediated apoptosis
Authors: Schniewind Bodo , Christgen Matthias , Kurdow Roland , Haye Sieglinde , Kremer Bernd , Kalthoff Holger , Ungefroren Hendrik
Published: January 2004

Palliative chemotherapy with gemcitabine, a common mode of treatment of pancreatic cancer, has little influence on patients' survival. We investigated the impact of anti‐apoptotic Bcl‐xL protein and its antagonist Bax on gemcitabine‐induced apoptosis in human pancreatic carcinoma cells in vitro and in vivo. The level of Bcl‐xL and Bax expression was determined in 3 established pancreatic cancer cell lines that differ in their sensitivity to gemcitabine‐mediated apoptosis. Bcl‐xL and Bax genes were transduced into Colo357 cells by retroviral infection. In addition, cells were transfected with c‐FLIP to assess involvement of CD95 and caspase‐8. The impact of Bax/Bcl‐xL expression on gemcitabine‐sensitivity in vivo was evaluated in orthotopic Colo357 tumors in SCID mice. The apoptotic index revealed a strong inverse correlation between Bcl‐xL expression and gemcitabine‐induced apoptosis in the pancreatic carcinoma cell lines tested. Caspase‐8 and Bid were cleaved in Colo357 cells exposed to gemcitabine, and there was no correlation with either Bcl‐xL or with Bax expression. In contrast, the lack of mitochondrial transmembrane potential transition, release of cytochrome‐c and absence of caspase‐9‐ and PARP‐cleavage showed a strong correlation with Bcl‐xL expression. Expression of c‐FLIP significantly increased the resistance towards gemcitabine. Orthotopically growing Colo357‐bcl‐xl tumors in SCID mice were refractory to gemcitabine treatment, and in contrast to the in vitro data, Colo357‐bax tumors exhibited a 12‐fold greater tumor regression than Colo357‐wild‐type tumors in the control group. Gemcitabine‐induced apoptosis involves the mitochondria‐mediated signaling pathway. A functional restoration of this pathway appears to be essential to overcome the resistance mechanisms of pancreatic tumor cells and to improve the response to therapy as demonstrated by Bax overexpression in a clinically relevant tumor model. © 2003 Wiley‐Liss, Inc.
MHC class I antigen processing pathway defects, ras mutations and disease stage in colorectal carcinoma
Authors: Atkins Derek , Breuckmann Aldona , Schmahl Gerd E. , Binner Priska , Ferrone Soldano , Krummenauer Frank , Störkel Stephan , Seliger Barbara
Published: January 2004

Colorectal tumorigenesis has been associated with the progressive acquisition of a variety of genetic alterations. These include mutations of the Ki‐ras proto‐oncogene in codons 12 and 13, which account for 85% of genetic changes in colorectal cancer. In murine in vitro models of oncogenic transformation, an association between ras‐mediated transformation and downregulation of different components of the MHC class I antigen processing machinery (APM) has been described. In order to investigate whether this association also exists in human tumors, 10 cases of high‐grade intraepithelial neoplasia (HIN), as well as primary tumors and autologous lymph node metastases from 42 patients with colorectal carcinoma, were monitored by allele‐specific restriction analysis for Ki‐ras mutations. In parallel, APM component expression and tumor cell proliferation were analyzed by immunohistochemistry. In comparison to autologous colorectal mucosa, TAP1, LMP2 and tapasin loss was found in 68%, 67% and 80% of HIN, respectively. In contrast, impaired TAP1, LMP2 and tapasin expression was found in 42%, 42% and 63% of primary adenocarcinomas of stage III disease and in 63%, 47% and 79% of the matched lymph node metastases, respectively. More than 60% of colorectal tumor lesions with TAP1, LMP2 and/or tapasin defects displayed Ki‐ras mutations. The frequency of TAP1, LMP2 and tapasin loss varied between 33% of primary adenocarcinomas, 40% of HIN to approximately 67% of metastases. These data suggest that i) APM component deficiencies occur more frequently in Ki‐ras‐mutated colorectal carcinoma lesions and ii) APM abnormalities in conjunction with Ki‐ras mutations appear to be associated with disease stage. These findings support the hypothesis that Ki‐ras mutations may contribute to immune escape mechanisms of tumors by downregulating the MHC class I APM component expression. © 2003 Wiley‐Liss, Inc.
Esophageal squamous cell cancer in patients with head and neck cancer: Prevalence of human papillomavirus DNA sequences
Authors: de Villiers Ethel‐Michele , Gunst Karin , Stein Harald , Scherübl Hans
Published: January 2004

An etiologic role for human papillomavirus (HPV) infections in either head and neck (HNC) or esophageal carcinogenesis remains debatable. Patients with head and neck cancer are at high risk for developing a second esophageal squamous cell cancer (ESCC). The aim of our study was to determine whether HPV infections play a role in this multifocal carcinogenesis. Samples from 2 groups of HNC patients were studied: Random esophageal biopsies were collected from the first group of 60 patients who had been screened for asymptomatic ESCC. The second group consisted of 21 patients with pairs of HNC and ESCC. Both the fresh frozen biopsy samples of the first group and the paraffin‐embedded specimens of the second group were evaluated for the presence of HPV DNA sequences by PCR amplification, cloning and sequencing. HPV DNA sequences were detected in 66.7% of normal/inflammatory (34/51) and dysplastic and malignant (6/9) esophageal tissues from HNC patients being screened endoscopically. Similarly, in the second group of 21 patients with both HNC and ESCC, HPV DNA sequences were demonstrated in 13 (61.9%) of the HNC biopsies and in 14 (66.7%) of the ESCC biopsies. The prevalence of high‐risk‐type HPV 16 was low (5/51, 9.8%) in normal/inflammatory esophageal mucosa but higher (10/24, 47.6%) in ESCC. The low‐risk HPV 11 was present in 37.3% (19/51) of normal/inflammatory, 66.7% (4/6) of dysplastic and 28.9% (13/45) of the carcinoma samples. The same HPV type was present in only 3/21 pairs of HNC and ESCC samples, suggesting that a clonal expansion from the HNC to a subsequent ESCC, or visa versa, is unlikely. The high prevalence of “low‐risk” HPV infections points to the need for studies on possible interactions of these infections with the use of alcohol and tobacco in the pathogenesis of these tumors. © 2003 Wiley‐Liss, Inc.
Effects of trastuzumab on epidermal growth factor receptor‐dependent and ‐independent human colon cancer cells
Authors: Kuwada Scott K. , Scaife Courtney L. , Kuang Jinqiu , Li Xiufen , Wong Robert F. , Florell Scott R. , Coffey Robert J. , Gray Phillip D.
Published: January 2004

Little information is available as to the potential role of HER‐2 as a therapeutic target in colon cancers, which express much fewer HER‐2 receptors than breast cancer cells. Treatment of certain human colon cancer cell lines with the HER‐2 inhibitory antibody mAb 4D5 demonstrated a role for HER‐2 in mediating proliferation, apoptosis and tumorigenicity. However, only the cell lines that were dependent on autocrine EGFR‐mediated cell proliferation were susceptible to the antiproliferative and antitumorigenic effects of HER‐2 inhibition. The relative levels of HER‐2, EGFR, HER‐3 and HER‐4 were not predictive of responsiveness to mAb 4D5. Treatment with HER‐2 antibodies caused a decrease in HER‐2 protein levels in all of the colon cancer cell lines and also significantly decreased EGFR levels but only in the EGFR‐dependent cell lines. Treatment with mAb 4D5 caused the rapid ubiquitination and ligand‐dependent downregulation of the EGFR in an EGFR‐dependent colon cancer cell line. Treatment of athymic mice engrafted with EGFR‐dependent colon cancer cells with mAb 4D5 caused tumor regression and a decrease in EGFR tyrosine phosphorylation in the tumor cells. EGFR‐independent colon cancer cell xenografts were resistant to mAb 4D5 therapy. Combined inhibition of HER‐2 and EGFR caused large areas of necrosis in EGFR‐dependent colon cancer xenografts, suggesting a benefit of combined HER‐2 and EGFR inhibitor therapy. Predicting clinical responsiveness of human colon cancer cells to anti‐HER‐2 and anti‐EGFR therapy may require demonstration of EGFR tyrosine kinase dependency of the cells. © 2003 Wiley‐Liss, Inc.
Fibre intake and prostate cancer risk
Authors: Pelucchi Claudio , Talamini Renato , Galeone Carlotta , Negri Eva , Franceschi Silvia , Dal Maso Luigino , Montella Maurizio , Conti Ettore , La Vecchia Carlo
Published: January 2004

Dietary fibre has been reported to protect from several neoplasms, but the issue remains controversial. No previous study considered in depth the topic of fibres and prostate cancer. A multicentre case‐control study was conducted in Italy from 1991 to 2002, including 1,294 men with incident, histologically confirmed prostate cancer and 1,451 controls admitted to the same network of hospitals as cases with acute nonmalignant conditions. Multivariate odds ratios (OR) and 95% confidence intervals (CI) were obtained after allowance for major identified confounding factors, including total energy intake. Compared to the lowest quintile, the OR of prostate cancer for the highest quintile of total fibre intake was 0.93 (95% CI 0.71–1.22). The risk was inversely related with soluble fibre (OR = 0.89, 95% CI 0.78–1.02, for a difference between 80th and 20th percentile), cellulose (OR = 0.88, 95% CI 0.78–1.01) and vegetable fibre (OR = 0.82, 95% CI 0.73–0.93). These relationships were consistent across strata of age, family history of prostate cancer, body mass index and education. Vegetable fibres appear, therefore, to have a favourable association with prostate cancer risk. © 2003 Wiley‐Liss, Inc.
Molecular analysis of PinX1 in medulloblastomas
Authors: Chang Qing , Pang Jesse Chung‐sean , Li Jing , Hu Landian , Kong Xiangyin , Ng Ho‐keung
Published: January 2004

Our group has previously demonstrated a high frequency of allelic loss on the short arm of chromosome 8 and identified a region of homozygous deletion of 1.41 Mb, flanked by D8S520 and D8S1130, on 8p23.1 in medulloblastomas, suggesting the presence of a tumor suppressor gene in this critical deletion region. The aim of our study was to investigate whether PinX1, a newly identified gene whose product is a potent inhibitor of telomerase, is the target gene in the homozygous deletion region identified in medulloblastomas. We assessed for alterations in gene sequence and transcript expression of PinX1, as well as the correlation between PinX1 expression and telomerase activity in a series of 52 medulloblastomas, 3 medulloblastoma cell lines (D283, D341 and Daoy) and 4 primitive neuroectodermal tumors (PNETs). Direct sequence analysis of all 7 exons and splice junctions of the PinX1 gene revealed no somatic mutations but 11 genetic polymorphisms. Transcript expression of PinX1, as evaluated by reverse transcription‐polymerase chain reaction, in microdissected tumors and normal cerebellum showed 2 transcript variants, corresponding to the full‐length form and an alternative spliced variant lacking exon 6, in all samples. This result indicated that PinX1 expression was not suppressed in medulloblastomas. Using the telomeric repeat amplification protocol (TRAP) assay, 13 of 19 (68%) medulloblastomas, 1 of 2 PNETs and all 3 cell lines showed telomerase activity. There is no significant correlation between PinX1 transcript expression and telomerase activity, but our results showed that telomerase activation is involved in medulloblastomas. Taken together, our results suggest that PinX1 does not play a major role in the oncogenesis of medulloblastomas. © 2003 Wiley‐Liss, Inc.
Apc10.1: An ApcMin/+ intestinal cell line with retention of heterozygosity
Authors: De Giovanni Carla , Landuzzi Lorena , Nicoletti Giordano , Astolfi Annalisa , Croci Stefania , Micaroni Massimo , Nanni Patrizia , Lollini Pier‐Luigi
Published: January 2004

APC10.1 is a new intestinal cell line derived from ApcMin/+ mice that retains both the heterozygous Apc genotype and a nonactivated Wnt signaling pathway and displays an early neoplastic phenotype. Although tumorigenic both in immunodepressed and in immunocompetent syngeneic mice, it requires a high cell dose and a long latency. Its epithelial/intestinal origin is shown, in a gene expression profile, by the expression of epithelial transcripts (such as cytokeratin and laminin isoforms) and of developmental regulatory genes (such as Tcf‐4, Hnf3β, p21, Ihh, Hes1) necessary for, or involved in, the maintenance of intestinal stem cells. The lack of activation of the Wnt cascade in APC10.1 cells is shown both by the expression profile of Wnt target genes and by the standard TCF reporter assay. APC10.1 cell line is a novel in vitro model that can contribute to a better understanding of the clinical evolution of familial adenomatous polyposis and to finding of new prophylactic and therapeutic approaches. Supplementary material for this article can be found on the International Journal of Cancer website at http://www.interscience.wiley.com/jpages/0020‐7136/suppmat/index.html.© 2003 Wiley‐Liss, Inc.
Mechanisms of genomic instability in human cancer: Insights from studies with human papillomavirus oncoproteins
Authors: Duensing Stefan , Münger Karl
Published: January 2004

Genomic instability is a hallmark of most human cancers including high‐risk human papillomavirus (HPV)‐associated anogenital neoplasia. The two HPV‐encoded oncoproteins, E6 and E7, can independently induce chromosomal abnormalities. We summarize the current state of knowledge concerning HPV‐induced genomic instability and discuss its significance in the context of human carcinogenesis. © 2003 Wiley‐Liss, Inc.
Identification of biomarkers for the initiation of apoptosis in human preneoplastic colonocytes by proteome analysis
Authors: Herzog Angelika , Kuntz Sabine , Daniel Hannelore , Wenzel Uwe
Published: January 2004

Development of resistance of cells toward proapoptotic signals is regarded as one of the key processes that allow tumor development. To identify proteins that are crucial for the initiation of apoptosis in NCOL‐1 human preneoplastic colonocytes, we analyzed the proteome of cells exposed to the flavonoids flavone and quercetin that differ in their ability to induce apoptosis although they possess similar structures. Both flavonoids inhibited proliferation and induced differentiation of NCOL‐1 cells but only quercetin committed the cells to apoptosis. The accessible proteome of NCOL‐1 cells was separated by 2D‐polyacrylamide‐gelelectrophoresis and proteins with changed expression level were identified by peptide mass fingerprints of tryptic digests of the protein spots. A pre‐fractionation of soluble and lipophilic proteins was used to enhance the resolution of analysis. After exposure to the test compounds for 24 hr, 73 proteins displayed changed steady state levels in case of quercetin and 32 in case of flavone. Several heat‐shock proteins, annexins and cytoskeletal caspase substrates were regulated by quercetin but not by flavone and these protein classes are known to play a role in apoptosis induction and execution. Whereas proteins like lamin A, C and desmoplakin, are indicators that apoptosis has already proceeded, others, such as annexin IV or protein kinase C‐beta play a pivotal role in the early phases of apoptosis. In conclusion, proteome analysis allowed the identification of marker proteins that are involved in the initiation of apoptotic cell death in preneoplastic colonocytes and those may help to develop new strategies for cancer prevention. © 2003 Wiley‐Liss, Inc.
Proliferation assay on a silicon chip applicable for tumors extirpated from mammalians
Authors: Torisawa Yu‐suke , Shiku Hitoshi , Kasai Shigenobu , Nishizawa Matsuhiko , Matsue Tomokazu
Published: January 2004

We describe a novel anticancer drug sensitivity assay on a silicon chip applicable for tumors extirpated from in vivo mammalians. Human promyelocytic leukemia (HL‐60) cells were subcutaneously (s.c.) inoculated in SCID mice, then removed 31 days after the inoculation. The cells were embedded in a small volume (18 nL) of a collagen‐gel matrix on a pyramid‐shaped silicon microstructure for further cultivation. The respiration activity of the cells on the chip was measured by scanning electrochemical microscopy (SECM). The proliferation behavior was continuously monitored for 6 days. It seemed that the proliferation rate of the cells removed from the mice was lower than that cultured in a flask and conformed to that in mice. The effects of cisplatin (CDDP) and etoposide (VP‐16) on the HL‐60 cultured in vivo were in good agreement with those obtained by a conventional colorimetric assay. Our results suggest that the SECM‐based assay is appropriate for biopsy specimens in a relatively short‐time evaluation. © 2003 Wiley‐Liss, Inc.
Acetylation of histones associated with the p21WAF1/CIP1 gene by butyrate is not sufficient for p21WAF1/CIP1 gene transcription in human colorectal adenocarcinoma cells
Authors: Kobayashi Hanako , Tan Er Mei , Fleming Sharon E.
Published: January 2004

Butyric acid is well recognized as a histone deacetylase (HDAC) inhibitor, and changes in histone acetylation are thought to alter gene expression. The mechanism by which sodium butyrate (NaB) induces p21WAF1/CIP1, a critical gene involved in the antiproliferative effect of NaB, was studied at the chromatin level. Using chromatin immunoprecipitation (ChIP) assay, acetylation of histone H3 was observed at the proximal region of the promoter within 30 min of NaB exposure and this extended to the distal region within 2 hr. By contrast, histone H4 was acetylated both at the proximal and the distal regions of the promoter within 30 min. NaB did not influence other histone modifications. NaB stimulated recruitment of the transcription factors ZBP89 and Sp1 as well as GCN5, but did not influence recruitment of Sp3, HDAC1, p300, or CBP. As recruitment of HDAC1 to the promoter appeared not to account for NaB‐induced changes in histone acetylation, we aimed to influence HDAC activity by altering its phosphorylation status. The kinase inhibitor, H7, suppressed p21WAF1/CIP1 mRNA in both the absence and the presence of NaB without influencing the butyrate‐induced hyperacetylation of H3 and H4 associated with the p21WAF1/CIP1 promoter. These results suggest that acetylation of histones at the p21WAF1/CIP1 promoter is not sufficient for NaB to exert antiproliferative effects via transcription of the p21WAF1/CIP1 gene. Induction of p21WAF1/CIP1 transcription by the phosphatase inhibitor, okadaic acid, in the absence of changes in association of acetylated histones with the p21WAF1/CIP1 promoter provides further evidence of the importance of phosphorylation to p21WAF1/CIP1 transcription. © 2003 Wiley‐Liss, Inc.
Promoter hypermethylation of E‐cadherin and its abnormal expression in Epstein‐Barr virus‐associated gastric carcinoma
Authors: Sudo Makoto , Chong Ja‐Mun , Sakuma Kazuya , Ushiku Tetsuo , Uozaki Hiroshi , Nagai Hideo , Funata Nobuaki , Matsumoto Yoshiro , Fukayama Masashi
Published: January 2004

Promoter hypermethylation of various tumor‐related genes is extremely frequent in Epstein‐Barr virus (EBV)‐associated gastric carcinoma (EBVaGC). To investigate the significance of the promoter methylation in EBVaGC, we focused on one of the important proteins in the carcinogenesis of the stomach, E‐cadherin. Methylation‐specific PCR analysis (MSP) was applied to surgically resected gastric carcinomas, together with immunohistochemistry, PCR‐based analysis of mutations and allelic loss, and site‐specific MSP of E‐cadherin gene. By MSP, nearly all of the carcinomas showed aberrant methylation of E‐cadherin promoter in EBVaGC (21/22), and the frequency of this aberration was significantly higher than that in EBV‐negative gastric carcinoma (GC; 45/81; p = 0.0003). According to immunohistochemistry of E‐cadherin, the frequency of abnormal staining pattern in EBVaGC (87%) was comparable to that in the diffuse type (80%), but higher than that in the intestinal type of EBV‐negative GC (47%). Promoter methylation was well correlated with abnormal staining pattern in EBVaGC, but not in EBV‐negative GC. Neither mutation nor allelic loss of E‐cadherin was observed in EBVaGC. Methylation status of E‐cadherin within each carcinoma was heterogeneous as far as examined. Thus, in addition to the known association involving p16, we determined that promoter methylation‐mediated silencing of E‐cadherin gene was also closely associated with the development of EBVaGC, although it becomes heterogeneous within a given tumor along its progression. © 2003 Wiley‐Liss, Inc.
Target cell‐restricted and ‐enhanced apoptosis induction by a scFv:sTRAIL fusion protein with specificity for the pancarcinoma‐associated antigen EGP2
Authors: Bremer Edwin , Kuijlen Jos , Samplonius Douwe , Walczak Henning , de Leij Lou , Helfrich Wijnand
Published: January 2004

The apparent tumor selective apoptosis‐inducing activity of recombinant soluble TNF‐related apoptosis‐inducing ligand (TRAIL) has aroused much interest for use in clinical application. However, to exploit fully its therapeutic potential, the characteristics of both the TRAIL receptor system and soluble TRAIL (sTRAIL) should be taken into account: first, the widespread expression of the various TRAIL receptors throughout the human body; second, the differential binding affinities and crosslinking requirements of the agonistic receptors TRAIL‐R1 and TRAIL‐R2; and third, the solution behavior of particular sTRAIL preparations. Therefore, we constructed a novel TRAIL fusion protein, designated scFvC54:sTRAIL, comprising the human scFv antibody fragment C54 genetically linked to the N‐terminus of human sTRAIL. The scFvC54:sTRAIL fusion protein was designed to induce apoptosis by crosslinking of agonistic TRAIL receptors only after specific binding of scFvC54:sTRAIL to the abundantly expressed carcinoma‐associated cell surface antigen EGP2 (alias EpCAM). Target antigen‐restricted apoptosis induction was demonstrated for various EGP2‐positive tumor cells and could be inhibited by an EGP2 competing antibody. Target antigen binding converted soluble scFvC54:sTRAIL into a membrane‐bound form of TRAIL that was capable of signaling apoptosis not only through TRAIL‐R1 but also through TRAIL‐R2. Size‐exclusion fast protein liquid chromatography (FPLC) indicated that scFvC54:sTRAIL was produced as stable and homogeneous trimers in the absence of detectable TRAIL aggregates. The favorable characteristics of the scFvC54:sTRAIL fusion protein potentially reduce the amount of sTRAIL required for antitumor activity and may be of value for the treatment of various human carcinomas. © 2003 Wiley‐Liss, Inc.
CDH1 and CDH13 methylation in serum is an independent prognostic marker in cervical cancer patients
Authors: Widschwendter Andreas , Ivarsson Lennart , Blassnig Anya , Müller Hannes M. , Fiegl Heidi , Wiedemair Annemarie , Müller‐Holzner Elisabeth , Goebel Georg , Marth Christian , Widschwendter Martin
Published: January 2004

Cervical cancer is the principal cause of death due to cancer in women. Five‐year survival rate ranges from 15–80%, depending on the extent of the disease. New predictive markers for relapse may increase survival rates by improving treatment of patients at high risk for relapse. The gene products of CDH1 and CDH13, namely E‐cadherin and H‐cadherin, play a key role in cell–cell adhesion. Inactivation of the cadherin‐mediated cell adhesion system, caused by aberrant methylation, is a common finding in human cancers. To test the hypothesis that CDH1/CDH13 methylation is a prognostic marker in cervical cancer we determined the methylation status of CDH1/CDH13 in serum samples from 93 cervical cancer patients. Methylation analysis was carried out using MethyLight. Aberrant methylation of the 5′‐region of CDH1 or CDH13 was observed in 43% (40 of 93) of the patients. Cervical cancer patients with unmethylated CDH1/CDH13 in serum samples showed significantly better disease‐free survival in univariate and multivariate analysis. Median disease‐free survival for CDH1/CDH13 methylation negative and positive patients was 4.3 years and 1.2 years, respectively. Our results suggest that detection of aberrant methylation of CDH1/CDH13 may be of potential use as a marker for selecting cervical cancer patients at high risk for relapse who could benefit from additional systemic therapy. © 2003 Wiley‐Liss, Inc.
Resveratrol modulates the phosphoinositide 3‐kinase pathway through an estrogen receptor α‐dependent mechanism: Relevance in cell proliferation
Authors: Pozo‐Guisado Eulalia , Lorenzo‐Benayas M. Jesús , Fernández‐Salguero Pedro M.
Published: January 2004

Resveratrol (RES), a natural phytoalexin, has antiproliferative activity in human‐derived cancer cells and in rodent models of tumor development. We have previously shown that RES induced apoptotic death in estrogen‐responsive MCF‐7 human breast cancer cells. Recent data have indicated that the estrogen receptor‐α (ERα), through interaction with p85, regulates phosphoinositide 3‐kinase (PI3K) activity, revealing a physiologic, nonnuclear function of the ERα potentially relevant in cell proliferation and apoptosis. In our study, using MCF‐7, we have analyzed the ability of RES to modulate the ERα‐dependent PI3K pathway. Immunoprecipitation and kinase activity assays showed that RES increased the ERα‐associated PI3K activity with a maximum stimulatory effect at concentrations close to 10 μM; concentrations >50 μM decreased PI3K activity. Stimulation of PI3K activity by RES was ERα‐dependent since it could be blocked by the antiestrogen ICI 182,780. RES did not affect p85 protein expression but induced the proteasome‐dependent degradation of the ERα. Nevertheless, the amount of PI3K immunoprecipitated by the ERα remained unchanged in presence of RES, indicating that ERα availability was not limiting PI3K activity. Phosphoprotein kinase B (pPKB/AKT) followed the pattern of PI3K activity, whereas RES did not affect total PKB/AKT expression. PKB/AKT downstream target glycogen synthase kinase 3 (GSK3) also showed a phosphorylation pattern that followed PI3K activity. We propose a mechanism through which RES could inhibit survival and proliferation of estrogen‐responsive cells by interfering with an ERα‐associated PI3K pathway, following a process that could be independent of the nuclear functions of the ERα. © 2003 Wiley‐Liss, Inc.
Endothelial cells co‐cultured with wild‐type and dominant/negative p53‐transfected glioblastoma cells exhibit differential sensitivity to radiation‐induced apoptosis
Authors: Khodarev Nikolai N. , Labay Edwardine , Darga Thomas , Yu Jianqing , Mauceri Helena , Gupta Nalin , Kataoka Yasushi , Weichselbaum Ralph R.
Published: January 2004

We performed expressional profiling of isogenic glioblastoma cell lines U87‐Lux8 and U87‐175.4. These cell lines differ in that U87‐Lux8 expresses wild‐type p53 and U87‐175.4 expresses a dominant‐negative p53 (175His mutation). DNA array analysis and real‐time PCR measurements demonstrated that basal expression and response to irradiation were different in these isogenic glioblastoma cell lines. These differences included genes involved in growth regulation and genes associated with cell‐to‐cell and cell/ECM communications. Co‐cultivation of U87‐175.4 and U87‐Lux8 with HUVE cells demonstrated that U87‐175.4 cells suppress the angiogenic phenotype of HUVEC and increase their sensitivity to radiation‐induced apoptosis compared to co‐culture of U87‐Lux8/HUVEC. These data suggest that blockade of p53 function may alter the communication between tumor cells and endothelial cells such that endothelial cells exhibit an increase in radiosensitivity. These findings may have important implications for the treatment of glioblastoma tumors and other human cancers. © 2003 Wiley‐Liss, Inc.
Genetic alterations in the peritumoral stromal cells of malignant and borderline epithelial ovarian tumors as indicated by allelic imbalance on chromosome 3p
Authors: Tuhkanen Hanna , Anttila Maarit , Kosma Veli‐Matti , Ylä‐Herttuala Seppo , Heinonen Seppo , Kuronen Arja , Juhola Matti , Tammi Raija , Tammi Markku , Mannermaa Arto
Published: January 2004

Stromal accumulation of hyaluronan in epithelial ovarian cancers is an independent predictor of tumor spreading and unfavorable outcome of the disease. We started to screen for chromosomal causes of this accumulation by studying deletions in 3p21.3, a region harboring 3 hyaluronidase genes (HYAL1‐3) among other potentially important tumor suppressors. Using 6 microsatellite markers from this region, allelic imbalance was found in 60–87% of the informative tumor cells microdissected from histologic sections of 58 patients with epithelial ovarian cancer. However, adjacent stromal cells originally intended as controls showed allelic imbalance at a frequency almost as high as the tumor cells (52–80%). A further laser capture microdissection on 10 borderline tumors also showed a high rate of allelic imbalance, both in the epithelial and stromal cells, but with a pattern slightly different from cancers. Allelic imbalance in the tumor epithelium or stroma was not correlated with the accumulation of hyaluronan or clinicopathologic parameters, including tumor stage and grade. The results suggest that factors other than inactivation of the HYAL1‐3 genes are responsible for hyaluronan accumulation in epithelial ovarian tumors. Moreover, the results indicate that the stromal cells of the epithelial ovarian cancers not only respond to the signals from malignant epithelium but also have themselves undergone genetic alterations in markers partly identical to those in the cancer epithelial cells and may actively contribute to the development of the tumor from its early stages to the late determinants of patient mortality. © 2003 Wiley‐Liss, Inc.
Analysis of the role of the leucine zipper motif in regulating the ability of AFAP‐110 to alter actin filament integrity
Authors: Qian Yong , Gatesman Amanda S. , Baisden Joseph M. , Zot Henry G. , Cherezova Lidia , Qazi Ihtishaam , Mazloum Nayef , Lee Marietta Y. , Guappone‐Koay Anne , Flynn Daniel C.
Published: January 2004

AFAP‐110 has an intrinsic ability to alter actin filament integrity as an actin filament crosslinking protein. This capability is regulated by a carboxy terminal leucine zipper (Lzip) motif. The Lzip motif facilitates self‐association stabilizing the AFAP‐110 multimers. Deletion of the Lzip motif (AFAP‐110Δlzip) reduces the stability of the AFAP‐110 multimer and concomitantly increases its ability to crosslink actin filaments, in vitro, and to activate cSrc and alter actin filament integrity, in vivo. We sought to determine how the Lzip motif regulates AFAP‐110 function. Substitution of the c‐Fos Lzip motif in place of the AFAP‐110 Lzip motif (AFAP‐110fos) was predicted to preserve the α‐helical structure while changing the sequence. To alter the structure of the α‐helix, a leucine to proline mutation was generated in the AFAP‐110 α‐helical Lzip motif (AFAP‐110581P), which largely preserved the sequence. The helix mutants, AFAP‐110Δlzip, AFAP‐110fos, and AFAP‐110581P, demonstrated reduced multimer stability with an increased capacity to crosslink actin filaments, in vitro, relative to AFAP‐110. An analysis of opposing binding sites indicated that the carboxy terminus/Lzip motif can contact sequences within the amino terminal pleckstrin homology (PH1) domain indicating an auto‐inhibitory mechanism for regulating multimer stability and actin filament crosslinking. In vivo, only AFAP‐110Δlzip and AFAP‐110581P were to activate cSrc and to alter cellular actin filament integrity. These data indicate that the intrinsic ability of AFAP‐110 to crosslink actin filaments is dependent upon both the sequence and structure of the Lzip motif, while the ability of the Lzip motif to regulate AFAP‐110‐directed activation of cSrc and changes in actin filament integrity in vivo is dependent upon the structure or presence of the Lzip motif. We hypothesize that the intrinsic ability of AFAP‐110 to crosslink actin filaments or activate cSrc are distinct functions. © 2003 Wiley‐Liss, Inc.
Characterization of DNA demethylation in normal and cancerous cell lines and the regulatory role of cell cycle proteins in human DNA demethylase activity
Authors: Vairapandi Mariappan
Published: January 2004

DNA methylation/demethylation constitutes a major consequence in all biological processes involving transcription, differentiation, development, DNA repair, recombination, and chromosome organization. Our earlier studies established that demethylation of CpG rich sequence by human DNA demethylase activity (5‐methylcytosine‐DNA glycosylase (5MeC‐DNA glycosylase)) resembles “base excision DNA repair activity” and creates single‐strand breaks on DNA that is associated with proliferating cell nuclear antigen (PCNA). Here in this report, we have identified differential DNA demethylation targets (hemi‐methylated vs. fully‐methylated) in normal cell lines and cancerous cell lines, and a shortened G0/G1 resting time in cancerous cell lines than the normal cell lines. We have identified that in normal HFL1 fibroblast cell line, DNA demethylase activity targets hemi‐methylated CpG specific sites on DNA. This normal cell line DNA demethylase activity associates with PCNA immune complex that is inhibited by CDKI proteins p21waf1/Gadd45α and Gadd45β. While in cancerous LnCap and BT20 cell lines DNA demethylase activity targets fully‐methylated CpG specific sites on DNA. This cancer cell line DNA demethylase activity is not associated with PCNA immune complex and is not inhibited by CDKI proteins p21waf1/Gadd45α and Gadd45β. We have also identified that the fully‐methylated CpG specific DNA demethylase activity from cancerous cell lines to associate with p300/CBP protein. These significant observations of variable targets of DNA demethylation and alternate partner proteins for DNA demethylase activity in cancerous cell lines are discussed in terms of double‐strand DNA breaks versus single‐strand DNA breaks and their role in the exit of G1/G2 cell cycle stages. Also, the inability of cell cycle regulatory proteins like PCNA, p21waf1, and Gadd45 to control DNA demethylase activity in cancerous cell lines is discussed in terms of accelerated G1/G2 cell cycle stage exit to facilitate unregulated cellular proliferation, loss of control of chromosomal organization, and the development of oncogenesis in cancerous cell lines. © 2003 Wiley‐Liss, Inc.
Effect of finasteride on risk of prostate cancer: How little we really know
Authors: Rubin Mark A. , Kantoff Philip W.
Published: January 2004

The Prostate Cancer Prevention Trial (PCPT) reported conclusively that finasteride prevents or delays the detection of prostate cancer. One perplexing finding was that more high‐grade tumors were detected in the finasteride treated group. It is hard to put this into perspective because of the limited published data on the effects of finasteride on prostate cancer. The strong possibility exists that the increase in high‐grade tumors may be due to a treatment effect, which causes intermediate grade cancers to appear to be high‐grade or aggressive tumors. Confirmation of a spurious tumor grade “inflation” will make the conclusions of this study clearer and define the benefits of finasteride chemoprevention in a more favorable light. © 2004 Wiley‐Liss, Inc.
Caldesmon phosphorylation is catalyzed by two kinases in permeabilized and intact vascular smooth muscle
Authors: Gorenne Isabelle , Su Xiaoling , Moreland Robert S.
Published: January 2004

Smooth muscle contraction is initiated by myosin light chain (MLC) phosphorylation catalyzed by the Ca2+ dependent MLC kinase. However, many aspects of smooth muscle contraction cannot be accounted for by MLC phosphorylation. One hypothesis that has received experimental support involves the thin filament protein caldesmon. Caldesmon inhibits myosin ATPase activity; phosphorylation of caldesmon relieves this inhibitory effect. The primary candidates for catalysis of caldesmon phosphorylation are the p42/p44 ERK MAP kinases. However, we and others have shown that inhibition of the ERK MAP kinases has no effect on many smooth muscles. The goal of this study was to determine if evidence for a second endogenous caldesmon kinase may be obtained. We used Triton X‐100 skinned and intact tissues of the swine carotid artery to address this goal. Caldesmon phosphorylation was evident in resting and Ca2+ stimulated Triton X‐100 skinned fibers. Ca2+‐dependent caldesmon phosphorylation was partially sensitive to the ERK MAP kinase inhibitor PD98059, whereas all caldesmon phosphorylation was sensitive to the general kinase inhibitor, staurosporine. Histamine increased caldesmon phosphorylation levels in intact swine carotid artery, which was sensitive to both PD98059 and staurosporine. Histamine increased ERK MAP kinase activity, which was reversed by PD98059, staurosporine, and EGTA. Histamine‐induced contractions were inhibited by staurosporine but not by PD98059. We interpret these results to suggest that although ERK MAP kinases catalyze caldesmon phosphorylation, a second staurosporine sensitive kinase is also important in caldesmon phosphorylation and it is this pathway that may be more important in contractile regulation. J. Cell. Physiol. 198: 461–469, 2004© 2003 Wiley‐Liss, Inc.
Subserous uterine adenomyosis mimicking an adnexal mass on sonography
Authors: La Fianza Alfredo , Abbati Daniela , Cesari Stefania , Morbini Patrizia
Published: January 2004

Uterine adenomyosis usually manifests as diffuse disease involving the myometrium and the endometrial‐myometrial junction, but it may also manifest as a focal lesion. It is usually only a few millimeters in diameter but may sometimes be larger. We report the case of a 32‐year‐old woman with a large isolated mass in the uterine wall. Transvaginal sonography demonstrated the cystic nature of the mass and its characteristic hemorrhagic pattern, whereas CT confirmed its uterine origin. The patient underwent laparoscopic resection of the mass, and pathologic examinations led to the diagnosis of adenomyosis. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:95–97, 2004
Counterclockwise barber‐pole sign on prenatal three‐dimensional power Doppler sonography in a case of duodenal obstruction without intestinal malrotation
Authors: Hsu Chin‐Yuan , Chiba Yoshihide , Fukui On , Sasaki Yoshihito , Miyashita Susumu
Published: January 2004

Three‐dimensional (3D) power Doppler sonographic imaging provides a 3D view of the blood vessels. This technique reportedly has advantages over other forms of sonography in visualizing normal and abnormal fetal vascular anatomy. We report the case of a 36‐year‐old pregnant woman in whom 3D power Doppler sonography with simultaneous gray‐scale imaging was performed at 32 weeks' gestational age to investigate an intestinal obstruction in the fetus that was suspected on the basis of 2‐dimensional sonographic findings. The 3D sonograms revealed that the superior mesenteric artery and vein of the fetus were wound counterclockwise, forming the “barber‐pole” sign. At 38 weeks' menstrual age, the female infant was delivered vaginally. Only duodenal atresia and annular pancreas, but not intestinal malrotation, were found postnatally. Surgical reconstruction of the duodenum was performed, with no major complications. Previous research suggests that the counterclockwise barber‐pole sign is a normal finding. On the basis of our case, we believe that this “negative finding” might be used to exclude the diagnosis of midgut volvulus, a condition that would be expected to cause these vessels to wrap around in a clockwise direction. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:86–90, 2004
Color Doppler sonographic signs of respiration‐dependent hepatofugal portal flow
Authors: Görg Christian , Seifart Ulf , Zugmaier Gerhard
Published: January 2004

Purpose

The role of respiration in modulating blood flow in the portal vein is unclear. The aim of this study was to investigate the phenomenon of respiration‐dependent periodic hepatofugal portal venous blood flow as detected on color Doppler sonography.

Methods

Within 1 year, we identified 13 patients with respiration‐dependent reversal of blood flow in the portal vein that was diagnosed on color Doppler sonography. This phenomenon was investigated by color Doppler sonographic examination of the portal venous flow during both mid‐inspiration breath‐holding and a respiratory cycle including deep inspiration; evaluation of hepatic vein Doppler waveforms as normal (triphasic) or decreased (flattened); and echocardiographic examination to determine the presence or absence of tricuspid regurgitation.

Results

The patients' median age was 53 years (range, 26–87 years). Seven of the 13 patients had heart disease (tricuspid regurgitation) with or without liver disease, 3 had liver disease without heart disease, and 3 had other diseases with no evidence of heart or liver disease. On Doppler sonography, 10 of the 13 patients had increased portal venous pulsatility (7 of the 10 had tricuspid regurgitation; the other 3 did not); the remaining 3 patients had neither increased pulsatility nor tricuspid regurgitation. Sonographic follow‐up within 4 weeks in 4 of the 13 patients revealed loss of the respiration‐dependent hepatofugal portal flow.

Conclusions

Respiration‐dependent hepatofugal portal flow is a rare finding associated with periodic portal hypertension in patients with right heart insufficiency and liver disease. Its clinical significance is unclear. Among our patients, its occurrence was predominantly associated with an increased venous pulsatility index due to tricuspid regurgitation or venous outflow obstruction. Further study is needed to investigate whether periodic respiration‐dependent hepatofugal portal flow is predictive of the occurrence of continuous flow reversal. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:62–68, 2004
Asymmetric parasitic dicephalus conjoined twins
Authors: Esenkaya Semra , Gürbüz Birgül , Yaltı Serap
Published: January 2004

In this report, we describe the case of a 19‐year‐old primigravida pregnant woman who had been hospitalized for 2 days with bleeding and a diagnosis of imminent abortion. Sonographic examination revealed a single fetus of approximately 17 weeks' gestation that initially appeared normal except for a mass on its neck. Further evaluation of the mass identified it as an anencephalic fetal head that was joined to the body with deformed cervical vertebrae. We diagnosed asymmetric parasitic dicephalus conjoined twins. The parents elected to terminate the pregnancy. Labor was induced, and the patient delivered a 20‐cm, 208‐g male fetus. The fetus had 4 normal limbs and a normal abdomen. Both its heads had a cleft lip, and its spine was Ų shaped with closed spina bifida at the spinal union in the thoracolumbar area. The patterns of conjoined twins are infinitely varied, but they can be generally classified according to standardized terms based on the anatomic site of their union. Cases of conjoined twins occur so rarely that it is important to learn as much as possible from each case. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:102–105, 2004
Migration of an intrauterine contraceptive device to the ovary
Authors: Özdemir Hüseyin , Mahmutyazıcıoğlu Kamran , Tanrıverdi H. Alper , Gündoğdu Sadi , Savranlar Ahmet , Özer Tülay
Published: January 2004

We present the case of a 37‐year‐old woman with a history of 2 consecutive insertions of intrauterine contraceptive devices (IUDs) 3 years before she was referred to us for sonographic evaluation of lower abdominal pain. The first of the IUDs was presumed to have been expulsed spontaneously, and 3 months after insertion of the second device, the patient had begun experiencing lower abdominal pain. Medical treatment with antibiotics and spasmolytics had been unsuccessful. We performed transvaginal sonography, which revealed the presence of an IUD in the uterus and a 2‐cm linear metallic echogenic area in the left ovary, believed to represent another IUD. Anteroposterior radiography confirmed that there were 2 IUDs in the pelvis, and CT demonstrated 1 IUD in the uterus and another in the left ovary. The patient underwent laparoscopic removal of the ovarian IUD and was discharged in good condition. To our knowledge, this is the first report of migration of an IUD to the ovary detected on transvaginal sonography. We recommend consideration of this possibility during evaluation of women with unexplained chronic pelvic pain. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:91–94, 2004
Characteristic sonographic findings of Warthin's tumor in the parotid gland
Authors: Kim Jinna , Kim Eun‐Kyung , Park Cheong Soo , Choi Yoon‐Seok , Kim Young Ho , Choi Eun Chang
Published: January 2004

Purpose

The aim of this study was to define the characteristic sonographic features of Warthin's tumors in the parotid gland, thus enhancing the ability to make a preoperative diagnosis of this disease process.

Methods

We retrospectively evaluated the sonograms of Warthin's tumors of the parotid gland that had been confirmed by histopathologic examination of surgically excised specimens from patients treated at our institution over a 2‐year period. We recorded the echogenicity, shape, margin, and internal structure of the tumors and categorized them into 2 groups on the basis of size (< 5 cm versus ≥ 5 cm in the largest diameter).

Results

Eighteen patients (16 men and 2 women) with a mean age of 57 years (range, 29–82 years) were included in the analysis. One patient had 2 tumors (1 in each parotid gland); the other 17 patients each had only 1 tumor. Our review of the sonographic findings revealed that all 19 tumors were hypoechoic compared with the normal parenchyma of the affected parotid glands. Most of the tumors were ovoid, had well‐defined margins, and contained multiple irregular, small, sponge‐like anechoic areas. Tumors that were 5 cm or greater in diameter had a higher proportion of cystic content than smaller lesions had and in some cases were composed almost entirely of cystic material.

Conclusions

Our evidence suggests that the sonographic appearance of a Warthin's tumor in the parotid gland is distinctive: a well‐defined round or ovoid hypoechoic mass containing microcystic anechoic areas. These sonographic features constitute useful criteria in the preoperative diagnosis of Warthin's tumor in the parotid gland, although sonographically guided fine‐needle aspiration biopsy may be needed to confirm the diagnosis. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:78–81, 2004