PubMed Health⌕ Search

Biomedical subjects

F X Real

Publications and source records attributed to F X Real.

At least 19 recordsLinked to original sources
PubMed2003

Gender-related differences in clinical and pathological characteristics and therapy of bladder cancer.

OBJECTIVE: To confirm the very high male:female ratios previously observed among Spanish bladder cancer patients and to assess gender differences in tumoral characteristics, diagnostic procedures, and treatment in a large series of consecutive bladder cancer patients. PATIENTS AND METHODS: All newly diagnosed bladder cancer patients (n=615) in 17 Spanish hospitals, between 1997-2000, were included. Information was collected both through personal interviews to patients and from medical records using a structured form. RESULTS: Seventy-six percent of tumours were superficial. The male:female ratio was 6.7 and it was similar for superficial and infiltrating tumours. Women were older than men at the diagnosis of bladder cancer (68.2+/-9.4 years versus 65.7+/-9.7 years, p=0.01). Ten percent of superficial tumours in women, versus 3% in men, were classified as "other histological types" (p=0.008). T1GIII tumours were more frequent among men (17% versus 7%, p=0.047). On the other hand, women were more likely to present with 0a-stage tumours (48.6% versus 35.5%, p=0.04), multiple tumours (50% versus 29%, trend test: 0.005), multi-centric tumours (54% versus 38%, p=0.019), and larger infiltrating masses (5.2 cm versus 3.8 cm, p=0.03) than men. Among 0a-stage tumours, only 23% of women compared to 54% of men received transurethral resection (TUR) alone (p=0.002). Women were almost five-fold more likely to receive additional therapies to TUR (p=0.004) after adjusting for age, geographical area, stage, tumoral size, nuclear grade, and multiplicity. CONCLUSION: The study confirms the very high male:female ratio of bladder cancer in Spain. We found substantial differences in the pathological characteristics of tumours from men and women. There was a tendency for women to receive more frequently non-standard, more aggressive, therapy than men.

Adult↗
PubMed2002

Family history of cancer and germline BRCA2 mutations in sporadic exocrine pancreatic cancer.

BACKGROUND: Hereditary factors have been reported in 5-10% of cases with exocrine pancreatic cancer and recent data support a role for BRCA2. AIMS: We have studied the prevalence of germline BRCA2 mutations in two groups of patients with exocrine pancreatic cancer from an unselected series in Spain: group A included 24 cases showing familial aggregation of cancer and group B included 54 age, sex, and hospital matched cases without such evidence. METHODS: Information was obtained by interview of patients and was validated by a telephone interview with a structured questionnaire. In patients from group A, >80% of the coding sequence of BRCA2 was analysed; in patients from group B, the regions in which germline BRCA2 mutations have been described to be associated with pancreatic cancer were screened. RESULTS: Telephone interviews led to reclassification of 7/54 cases (13%). Familial aggregation of cancer was found in 24/165 cases (14.5%); six patients had a first degree relative with pancreatic cancer (3.6%) and nine patients had relatives with breast cancer. Germline BRCA2 mutations were not identified in any patient from group A (0/23). Among group B cases, one germline variant (T5868G>Asn1880Lys) was found in a 59 year old male without a family history of cancer. The 6174delT mutation was not found in any of the 71 cases analysed. CONCLUSIONS: The overall prevalence of BRCA2 mutations among patients with pancreatic cancer in Spain is low and the 6174delT mutation appears to be very infrequent. Our data do not support screening patients with cancer of the pancreas for germline BRCA2 mutations to identify relatives at high risk of developing this tumour.

Adult↗
PubMed2001

Regulation of mucin and glycoconjugate expression: from normal epithelium to gastric tumors.

Gastric epithelium is protected by a mucus layer rich in MUC5AC and MUC6 mucins synthesised by the superficial epithelium and the glands, respectively. These cell populations also express specific fucosyltransferases that determine the glycosylation pattern of these gastric mucins. The maintenance of the structure and properties of the gastric mucus has been related to the degree of glycosylation and the oligomeric forms of the mucins. In gastric tumors, and in early preneoplastic lesions such as intestinal metaplasia, the glycosylation pattern detected in normal stomach is lost and, intestinal mucins, MUC2 and MUC4, can be ectopically detected in the gastric epithelium. These changes are biologically relevant because the binding of Helicobacter pylori to the gastric mucosa is mediated by blood group-related antigens. In vitro and animal models allowing the study of the gastric ecological niche and the requirements for its maintenance are essential for an understanding of the role of bacterial-mucosal interactions in pathological processes such as inflammation and cancer.

Animals↗
PubMed2001

Genetic profile of 22 pancreatic carcinoma cell lines. Analysis of K-ras, p53, p16 and DPC4/Smad4.

The K-ras, p53, p16 and DPC4 genes are among those most frequently altered in pancreatic ductal carcinoma. We analyzed 22 cell lines for alterations in these genes by direct sequence analysis and methylation-specific polymerase chain reaction. These cell lines showed mutations in K-ras and p53 at frequencies of 91% and 95%, respectively. Alterations in p16INK4a were found in all cases and included nine homozygous deletions, seven mutations and promoter methylation in six cases. Eight cell lines (36%) had an alteration of DPC4, including one mutation and seven homozygous deletions. The most typical mutational profile involved K-ras, p53, and p16INK4a, concurrently aberrated in 20 cases (91%). Eight cell lines had alterations in all four genes. Inactivation of DPC4 was always accompanied by alteration of all of the other three genes. This comprehensive data regarding the cumulative genetic alterations in pancreatic carcinoma cell lines will be of great value for studies involving drug sensitivity or resistance that may be associated with inactivation of a particular gene or molecular pathway.

Carcinoma, Pancreatic Ductal↗
PubMed2001

Cystic fibrosis transmembrane regulator (CFTR) DeltaF508 mutation and 5T allele in patients with chronic pancreatitis and exocrine pancreatic cancer. PANKRAS II Study Group.

BACKGROUND: An increased risk of chronic pancreatitis has been described among carriers of the cystic fibrosis transmembrane regulator (CFTR) mutation. In addition, patients with cystic fibrosis may have a higher risk of exocrine pancreatic cancer. AIMS: To determine the prevalence of the DeltaF508 mutation and 5T allele, the most common CFTR disease related variants, and to assess their association with lifestyle factors in an unselected series of patients with chronic pancreatitis or pancreatic cancer. SUBJECTS: Patients recruited to the multicentre PANKRAS II study with a diagnosis of chronic pancreatitis and pancreatic cancer from whom normal DNA was available. METHODS: The DeltaF508 mutation and 5T allele were analysed using polymerase chain reaction amplified normal DNA. Information on clinical and lifestyle factors was obtained through personal interviews. RESULTS: Among patients with pancreatitis, no DeltaF508 alleles were found and the prevalence of the 5T allele was 10.5%, similar to that described in the general population. Among patients with pancreatic cancer, the prevalence of the DeltaF508 mutation and the 5T allele was 2.4% and 5.5%, respectively. 5T allele carriers with cancer consumed significantly less alcohol than non-carriers (p=0.038). CONCLUSIONS: Our findings do not support the view that the DeltaF508 mutation and 5T allele confer a higher risk of chronic pancreatitis or pancreatic cancer. Nevertheless, our data suggest that interactions between CFTR polymorphism and environmental factors may play a role in the pathogenesis of these diseases. Our study emphasises the need for a multinational study to conclusively establish the role of CFTR variants as genetic susceptibility factors for chronic pancreatitis and pancreatic cancer.

Adenocarcinoma↗
PubMed2001

Mucins as differentiation markers in bronchial epithelium. Squamous cell carcinoma and adenocarcinoma display similar expression patterns.

UNLABELLED: Highly glycosylated apomucins are important to maintain the viscoelastic properties of the mucus. Changes in their expression are frequently associated with inflammatory and neoplastic conditions. We analyzed the expression of apomucins in normal respiratory tract (n = 8) and compared it with distal, peritumoral, and tumoral epithelia from patients with squamous cell carcinoma (n = 20), adenocarcinoma (n = 13), and small cell carcinoma (n = 12). Squamous metaplasia (n = 16) was also analyzed. MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC8 apomucins were detected by immunohistochemistry, and mucin transcripts by in situ hybridization and reverse transcriptase polymerase chain reaction. Bronchial epithelium from normal individuals and distal epithelium from cancer patients showed a similar expression pattern: MUC1, MUC4, and MUC8 were always present, MUC2 and MUC5AC showed more variability, and MUC6 was focally detected. MUC5AC was downregulated in peritumoral epithelium and in squamous metaplasia, and MUC6 was upregulated in peritumoral epithelium. A reduced expression of MUC4, MUC5AC, and MUC8 was observed in non-small cell carcinomas, regardless of their histologic subtype. In small cell tumors, only MUC1 was consistently expressed. CONCLUSIONS: (1) peritumoral epithelium and squamous metaplasia show an abnormal pattern of mucin expression; (2) squamous cell carcinomas and adenocarcinomas display a similar pattern of mucin gene expression, supporting the concept of a common cellular origin.

Adenocarcinoma↗
PubMed2001

Differential distribution of sialic acid in alpha2,3 and alpha2,6 linkages in the apical membrane of cultured epithelial cells and tissues.

We used lectin cytochemistry and confocal microscopy to examine the distribution of sialic acid in epithelial cells. Maackia amurensis lectin and Sambuccus nigra agglutinin were used to detect alpha2,3 and alpha2,6 sialic acid, respectively. In Caco-2, HT-29 5M12, and MCF-7 cells, which express sialic acid mainly in one type of linkage, the majority of the signal was observed in the apical membrane. In cells that bound both lectins, alpha2,3 sialic acid was distributed apically, whereas alpha2,6 sialic acid showed a broader distribution. In IMIM-PC-1 cultures, alpha2,3 sialic acid was detected mainly in the apical membrane, whereas alpha2,6 sialic acid was more abundant in the basolateral domain of polarized cells. In these cells, treatment with GalNAc-O-benzyl led to reduced alpha2,3 levels and to an increase and redistribution of alpha2,6 to the apical domain. Similarly, sialic acid was predominantly expressed apically in all epithelial tissues examined. In conclusion, (a) sialic acid is mainly distributed to the apical membrane of epithelial cells, (b) there is a hierarchy in the distribution of sialic acids in polarized epithelial cells, i.e., alpha2,3 is preferred to alpha2,6 in the apical membrane, and (c) IMIM-PC-1 cells are a good model in which to study the regulation of the levels and distribution of sialic acids.

Acetylgalactosamine↗
PubMed2000

Detection of HuD transcripts by means of reverse transcriptase and polymerase chain reaction: implications for the detection of minimal residual disease in patients with small cell lung cancer.

Small cell lung cancer (SCLC) expresses neuroectodermal markers including HuD, the best characterized member of the Hu gene family. The aim of this study is to optimize a simple and sensitive reverse transcriptase-polymerase chain reaction assay to detect circulating HuD-expressing cells for the early detection of SCLC recurrences. HuD-specific primers that selectively amplify the three HuD isoforms allowed the detection of one tumor cell/10(6) non-tumor cells. However, HuD transcripts were also detected in the mononuclear fraction of all samples from normal individuals (n=6) and patients with SCLC (n=5). By contrast, HuD protein was not detected in these fractions using Western blotting. More quantitative assays are necessary to examine the value of HuD transcript detection for the identification of tumor recurrences.

Alternative Splicing↗
PubMed2000

The 18q21 region in colorectal and pancreatic cancer: independent loss of DCC and DPC4 expression.

UNLABELLED: The 18q21 region is frequently altered in gastrointestinal tumors. Three candidate tumor suppressor genes have been identified in it: DCC, Smad4/DPC4 and Smad2; the mechanisms involving their inactivation have not been completely elucidated. In this study, genetic losses at 18q21 and expression of DCC and DPC4 in colorectal (n=12) and pancreatic (n=16) cell lines and in colorectal tissues (n=10) were analyzed. The status of the 18q21 region was assessed using microsatellite analysis and duplex PCR of exonic sequences; expression was analyzed by RT-PCR; mutational analysis of DPC4 cDNA was performed in selected cases. Homozygous losses of microsatellite markers at 18q21 were not observed in colon or pancreas lines; however, a higher proportion of apparent homozygosity than expected was found. DCC and DPC4 transcripts were detected in 11/12 and 12/12 colorectal cancer lines, respectively. In tumors, homozygous losses at 18q21 were detected in three cases, without affecting DCC. All tumors retained DCC and DPC4 mRNA expression. In pancreatic lines, DPC4 was inactivated through homozygous deletion (n=5), intragenic mutation (n=3), and lack of protein (n=2). IN CONCLUSION: (1) microsatellite analysis does not provide adequate information regarding homozygous losses at 18q21; (2) approximately 65% of pancreas cancer lines show inactivation of DPC4; and (3) loss of DCC and DPC4 occur independently.

Aged↗
PubMed2000

GalNAc-alpha -O-benzyl inhibits sialylation of de Novo synthesized apical but not basolateral sialoglycoproteins and blocks lysosomal enzyme processing in a post-trans-Golgi network compartment.

Glycosylation plays an important role in glycoprotein traffic. Our previous work has shown that long term treatment of mucus-secreting HT-29 cells with GalNAc-alpha-O-benzyl reversibly inhibits sialylation and causes the accumulation of apical glycoproteins in cytoplasmic vesicles. We have analyzed at the biochemical level the effects of GalNAc-alpha-O-benzyl on glycoprotein processing. Both apical and basolateral membrane glycoproteins were sialylated, but GalNAc-alpha-O-benzyl selectively inhibited the sialylation of apical glycoproteins. In addition, lysosomal alpha-glucosidase, which is partially targeted to the apical membrane, was abnormally processed leading to the accumulation of an immature molecular species. Several findings support the conclusion that accumulation of this protein occurs in a post-trans-Golgi network (TGN) compartment: 1) it is partially sialylated; 2) it does not occur when glycoprotein exit from the TGN is blocked at 20 degrees C; 3) upon Triton X-114 partition, it distributes to the aqueous phase, a characteristic that is acquired in a post-TGN compartment; and 4) its appearance is inhibited when cells are cultured in the presence of NH(4)Cl. The processing of cathepsin D was also found to be affected by GalNAc-alpha-O-benzyl treatment. In conclusion, GalNAc-alpha-O-benzyl selectively inhibits sialylation of apical glycoproteins and perturbs lysosomal enzyme processing; these effects occur in a post-TGN acidic compartment and are reminiscent of the alterations found in sialic acid storage diseases.

Acetylgalactosamine↗
PubMed2000

Validity of the hospital discharge diagnosis in epidemiologic studies of biliopancreatic pathology. PANKRAS II Study Group.

BACKGROUND: The aim was to analyse the magnitude, direction and predictors of change in the main hospital discharge diagnosis (HDD) after a clinical expert review, among patients included in a multicentre molecular epidemiologic study of biliopancreatic diseases. METHODS: A total of 602 patients with a suspicion diagnosis of pancreas cancer (PC), cancer of the extrahepatic biliary system (CEBS) or benign biliopancreatic pathologies (BPP) were prospectively recruited at five general hospitals. A structured form was used to collect information from medical records. A panel of experts revised all diagnostic information and established the main clinicopathological diagnosis (CPD) by consensus. RESULTS: Of the 204 cases with a HDD of PC, 176 (86%) were deemed to have a CPD of PC, eight of CEBS, twelve a neoplasm of different origin, four BPP and four syndromic diagnoses. Thus, 28 cases (14%) were false positives. Of the 129 patients with a HDD of CEBS, 15 (12%) were false positives. Nine of the 396 cases with a HDD of non-PC (2%) had a CPD of PC (false negatives), whilst 14 of 471 patients with a HDD of non-CEBS (3%) were deemed to have CEBS. Overall, sensitivity and specificity of HDD for PC were, respectively, 95 and 93%, and for CEBS, 89 and 97%. Cytohistological confirmation and laparotomy were independent predictors of diagnostic change. CONCLUSIONS: Validity of the HDD was high, but its association with some clinical variables suggests that sole reliance on HDD can significantly bias results, and highlights the need to review all HDDs. Alternatively, only patients at high risk of misdiagnosis could be reviewed: primarily, those lacking a cytohistological diagnosis or a laparotomy. No exclusions appear warranted solely on the basis of age, gender or tumour spread.

Aged↗
PubMed2000

Role of fucosyltransferases in the association between apomucin and Lewis antigen expression in normal and malignant gastric epithelium.

BACKGROUND: In normal gastric epithelium, MUC5AC is detected in superficial epithelium associated with Lewis type 1 antigens and MUC6 is detected in antral glands with Lewis type 2. Therefore, the stomach constitutes an excellent model to examine the role of glycosyltransferases in determining the specificity of apomucin glycosylation. AIMS: To determine the molecular basis of this association and to examine changes in expression of gastric and intestinal apomucins and their association with Lewis antigens during the gastric carcinogenesis process. METHODS: Fucosyltransferase (FUT1, FUT2, FUT3) and mucin (MUC5AC, MUC6) transcripts were detected using reverse transcription-polymerase chain reaction. Apomucin (MUC2, MUC4, MUC5AC, MUC6) and Lewis antigen (types 1 and 2) expression were analysed using single and double immunohistochemistry and in situ hybridisation. RESULTS: In the normal stomach, FUT1 is exclusively detected associated with MUC6; FUT2 is only detected when MUC5AC is present. This co-regulation is lost in gastric tumours, as is differential expression of MUC5AC and MUC6 in normal gastric epithelial cells. In gastric tumours, especially those with the intestinal phenotype, MUC2 and MUC4 genes are upregulated, and gastric-type and intestinal-type mucins are coexpressed. These changes are early events in the gastric carcinogenesis process, as they are detected in intestinal metaplasia. CONCLUSIONS: The glycosylation pattern found in normal gastric epithelium is dictated by the specific set of fucosyltranferases expressed by the cells rather than by the apomucin sequence. The development of intestinal metaplasia and gastric cancer is associated with the appearance of cellular phenotypes that are absent from normal epithelium.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed2000

Role of the basic helix-loop-helix transcription factor p48 in the differentiation phenotype of exocrine pancreas cancer cells.

The majority of human pancreatic adenocarcinomas display a ductal phenotype; experimental studies indicate that tumors with this phenotype can arise from both acinar and ductal cells. In normal pancreas acinar cells, the pancreas transcription factor 1 transcriptional complex is required for gene expression. Pancreas transcription factor 1 is a heterooligomer of pancreas-specific (p48) and ubiquitous (p75/E2A and p64/HEB) basic helix-loop-helix proteins. We have examined the role of p48 in the phenotype of azaserine-induced rat DSL6 tumors and cancers of the human exocrine pancreas. Serially transplanted acinar DSL6 tumors express p48 whereas DSL6-derived cell lines, and the tumors induced by them, display a ductal phenotype and lack p48. In human pancreas cancer cell lines and tissues, p48 is present in acinar tumors but not in ductal tumors. Transfection of ductal pancreas cancers with p48 cDNA did not activate the expression of amylase nor a reporter gene under the control of the rat elastase promoter. In some cell lines, p48 was detected in the nucleus whereas in others it was cytoplasmic, as in one human acinar tumor. Together with prior work, our findings indicate that p48 is associated with the acinar phenotype of exocrine pancreas cancers and it is necessary, but not sufficient, for the expression of the acinar phenotype.

Adenocarcinoma↗
PubMed1999

Expressed sequence tag (EST) phenotyping of HT-29 cells: cloning of ser/thr protein kinase EMK1, kinesin KIF3B, and of transcripts that include Alu repeated elements.

To study the mechanisms that control epithelial commitment and differentiation we have used undifferentiated HT-29 colon cancer cells and a subpopulation of mucus secreting cells obtained by selection of HT-29 cells in 10-6 M methotrexate (M6 cells) as experimental models. We isolated cDNAs encoding transcripts overexpressed in early confluent M6 cells regarding steady-state levels in HT-29 cells by subtractive hybridisation. Fifty-one cDNA clones, corresponding to 34 independent transcripts, were isolated, partially sequenced by their 5' end, and classified into four groups according to their identity: transcripts that included a repeated sequence of the Alu family (10 clones, among them those encoding ribonucleoprotein RNP-L and E-cadherin), transcripts encoded by the mitochondrial genome (nine clones), transcripts encoding components of the protein synthesis machinery (23 clones, including the human ribosomal protein L38 not previously cloned in humans) and nine additional cDNAs that could not be classified in the previous groups. These last included ferritin, cytokeratin 18, translationally controlled human tumour protein (TCHTP), mt-aldehyde dehydrogenase, as well as unknown transcripts (three clones), and the human homologues of the molecular motor kinesin KIF3B and of the ser/thr protein kinase EMK1. Spot dot and Northern blot analyses showed that ser/thr protein kinase EMK1 was differentially expressed in M6 cells when compared with parental HT-29 cells. Steady-state levels of EMK1 were higher in proliferating, preconfluent, M6 and HT-29 cells than in 2 days post confluence (dpc) and 8dpc M6 and HT-29 cells. Transcripts that included an Alu repeat were also shown to be differentially expressed and accumulated in differentiating M6 cells when analysed by Northern blot. The significance of the transcripts cloned is discussed in the context of the commitment and differentiation of the M6 cells to the mucus secreting lineage of epithelial cells.

Alu Elements↗
PubMed1999

In vitro analysis of the role of DCC in mucus-secreting intestinal differentiation.

The deleted in colorectal cancer (DCC) gene was initially described as a colon cancer-associated tumor suppressor gene and subsequently proposed to be involved in goblet cell differentiation, but its precise role in normal intestine physiology and in cancer remains to be established. We have analyzed DCC mRNA expression in a panel of human colorectal cancer cell lines with a variety of differentiation phenotypes by reverse transcription-polymerase chain reaction (RT-PCR) and have shown that (1) most cell lines showed lower levels of DCC mRNA than normal colonic tissue; (2) only 1 cell line lacked detectable levels of DCC mRNA expression; (3) a discrepancy was found between the detectability of RT-PCR products corresponding to the extracellular and intracellular domains of DCC; and (4) there was no association between the presence of DCC transcripts and the differentiation phenotype. Specifically, DCC was not exclusively associated with the mucus-secreting phenotype, as determined by Alcian blue staining and Northern blotting with mucin gene probes. This was further supported by immunohistochemical results on DCC product and mucins in normal colon: DCC was detected in both goblet and absorptive cells. The introduction of full-length DCC cDNA in undifferentiated HT-29 cells did not have any effect on their differentiation phenotype, as shown by morphological studies and analysis of markers for this process in colon, such as mucins, dipeptidylpeptidase IV, villin and sucrase-isomaltase. There were no effects on cell proliferation in vitro. Our results indicate that DCC is not selectively involved in the mucosecretory differentiation pathway and that it is neither sufficient nor essential for normal intestinal differentiation.

Cell Adhesion Molecules↗