Low value of detection of KRAS2 mutations in circulating DNA to differentiate chronic pancreatitis to pancreatic cancer.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to O Gandini.
Explore the source record for details and available documents.
BACKGROUND: It has been suggested that progression of superficial bladder cancer may be regulated at the molecular level by a typical pattern of expression of genes involved in apoptosis. Recently LIVIN, belonging to the inhibitors of apoptosis (IAP) family, has been found to be expressed in most solid tumors, where its expression is suggested to have prognostic significance. No data are available concerning the significance of LIVIN in the progression of bladder tumors. PATIENTS AND METHODS: In the present paper we used RT-PCR to investigate the expression of LIVIN isoforms alpha and beta, SURVIVIN, BCL-X and BCL-2/BAX expression ratio both in normal and tumoral bladder tissues, and correlated their expression with the emergence of early relapses in a follow-up of 4 years. This study shows that only the alpha isoform of LIVIN, which is not expressed in normal bladder tissue, is expressed in a proportion of tumors with a high risk of relapse. RESULTS: LIVIN was found in 7/30 patients (23%), SURVIVIN in 9/30 (30%), BCL-2/BAX ratio >1 in 16/30 (53%), BCL-2/BAX expression ratio <1 in 14/30 (46.6%) and BCL-X, only in isoform BCL-X(L), in 11/30 (36.6%). When we evaluated the dependence between each gene expression and relapse free time of patients, we found that LIVIN, high BCL-2/BAX ratio and BCL-X(L), but not SURVIVIN, reached statistical significance in order to predict relapses. CONCLUSIONS: Our findings suggest that LIVIN may be involved in the progression of superficial bladder cancer and used as a marker of early recurrence; while the expression of SURVIVIN cannot be used to identify patients with high risk of relapse.
Kidney and liver are the major organs of erythropoietin (Epo) synthesis. However, Epo messenger RNA (mRNA) has been detected in several organs, such as brain, lung, and testis. Furthermore, functional Epo receptors have been demonstrated on different cell types, including rat Leydig cells. The aim of the study was to identify testicular cells expressing Epo mRNA and to quantitate its levels by competitive reverse transcriptase-polymerase chain reaction (RT-PCR). Besides whole testis, Epo transcripts were found in Sertoli and peritubular myoid cells, while no signal was detected in Leydig cells. Exposure of Sertoli cells to CoCl(2) led to an increase of Epo mRNA level. Semiquantitative competitive RT-PCR presented an increase in the level of Epo mRNA in Sertoli cells stimulated by follicle-stimulating hormone, while exposure of peritubular myoid cells cultures to testosterone reduced Epo mRNA expression. Due to the blood-testis barrier, basal expression of Epo suggests a not yet defined function of this hormone in testis.
PROBLEM: Neither the integrin pattern nor the biological functions of integrins have been extensively documented in human cultured testicular peritubular myoid cells (TPMC). The integrin pattern and the presence of some proteins of the immunoglobulin superfamily on human TPMC as well as the role of integrins in TPMC contraction were examined. METHOD OF STUDY: Integrin expression was evaluated by immunofluorescence and FACS analysis. To assess the role of integrin in TPMC contraction, human and rat cells were added to a collagen gel system and exposed to contractile stimuli. RESULTS: The immunofluorescence and cytofluorimetric analysis showed that human cultured TPMC express alpha1, alpha2, alpha3, alpha4, alpha5, alpha6, alphav, beta1, beta3, and beta4 integrin subunits, and significant amounts of intercellular adhesion molecule-1 (ICAM-1), whereas they do not present alpha4, beta2, beta7 subunits, nor intercellular adhesion molecule-2 (ICAM-2) and neural cell adhesion molecule (NCAM). The preincubation of human cells with an anti-beta1 mAb and of rat cells with a polyclonal anti-beta1 antibody inhibited TPMC contraction induced by different contractile stimuli. CONCLUSION: Our investigation documented a broad integrin pattern on human cultured TPMC as well as a role for integrins in human and rat TPMC contraction.
Despite the large number of studies performed in solid tumors, few attempts at molecular detection of urothelial cells in blood have been made. Specifically, only uroplakin II (UP-II) and cytokeratin 20 (CK-20) have been suggested as tumor markers in the blood of bladder cancer patients. Epidermal growth factor receptor (EGFR) mRNA expression was found in the blood of patients with some types of carcinoma; nevertheless, its expression has been never investigated in the blood of patients with urothelial tumors. We used a EGFR-based reverse transcription-PCR assay for the detection of tumoral cells in the blood of 27 patients with bladder cancer, in 30 healthy donors, and in 9 patients with cystitis. EGFR expression was compared with that of known markers of circulating epithelial cells, CK-19 and CK-20, and to a urothelial-specific marker, UP-II. Analysis by reverse transcription-PCR and Southern blot hybridization showed no evidence of EGFR and UP-II mRNA expression in any of the samples used as controls. Analysis of healthy donors showed mRNA expression for CK-19 and CK-20 in 6 of 30 and in 4 of 30 samples, respectively. All patients with cystitis resulted negative for EGFR expression, whereas 3 of 9, 2 of 9, and 3 of 9 were found expressing CK-19, CK-20, and UP-II, respectively. Among blood samples from tumoral patients, 74% had EGFR mRNA and 41% had positive signals for CK-19, whereas positivity for CK-20 and UP-II was found in 15% and 37% of patients, respectively. These results seem to indicate that EGFR mRNA in the blood may be a useful tumor marker in bladder cancer patients, as well as in other patients with epithelial tumors.
OBJECTIVE: To analyze the role of the transforming growth factor (TGF)-beta pathway in renal tumors and to verify whether alterations in TGF-beta 1 pathway expression are associated with the grade of tumor differentiation and pathologic stage in renal cell carcinomas. STUDY DESIGN: The expression of TGF-beta 1 and TGF-beta receptors (T beta RI and T beta RII), SMAD-2 and SMAD-4 was investigated by immunohistochemistry in normal peritumoral and tumoral tissue from 53 renal cell carcinomas (clear cell type). The gene expression of SMAD-2 and SMAD-4 was also studied by reverse transcription polymerase chain reaction (RT-PCR) in normal peritumoral and tumoral tissue from 6 of 56 primary tumors. RESULTS: TGF-beta 1, T beta RI and T beta RII immunoreactivity was more frequent in tumoral than in normal peritumoral renal tissue (96.22%, 79.25% and 75.41% vs. 88.37%, 69.76% and 62.69%), whereas SMAD-2 and SMAD-4 immunoreactivity was more frequent in normal peritumoral than in tumoral tissue (23.25% and 30.23% vs. 15.09% and 7.54%). In tumor areas, immunohistochemical scores were lower for T beta RII than for T beta RI and TGF-beta 1 and higher than SMAD-4 and SMAD-2 scores. TGF-beta 1, T beta RI, T beta RII and SMAD-4 histologic scores correlated with neither the histologic grade of malignancy nor TNM clinical stage, whereas SMAD-2 protein levels were significantly lower in grade 3 than in grade 1 tumors. In the samples of normal kidney and carcinoma studied, RT-PCR detected the correct transcripts for SMAD-2 and SMAD-4, indicating that the RNA of the samples analyzed contained RNA sequences coding for these genes. CONCLUSION: Our data support the concept that the reduction of T beta RII and SMAD proteins in renal cell carcinomas is involved in tumor development and suggest an altered TGF-beta/SMAD signaling pathway in kidney neoplasia.
Uridine diphosphoglucuronosyltransferases (UGTs) are detoxifying enzymes responsible for the metabolism of endogenous and xenobiotics compounds. UGT isoforms are widely distributed in rat tissues showing a constitutive and inducible gene expression. However, little information is available concerning UGTs expression in testis. The UGT1A1, UGT1A2, and UGT1B1 mRNAs expression in whole rat testis, in Sertoli and peritubular myoid cells in basal conditions, and after hormonal and hypoxic stimulation were investigated by reverse transcriptase-polymerase chain reaction (RT-PCR). Constitutive expression of each UGT1 isoform was present in rat testis with higher levels of UGT1A2. UGT transcripts were also detected in Sertoli and peritubular myoid cells. After FSH stimulation, Sertoli cells showed an increase in UGT1B1 mRNA expression, whereas the levels of UGT1A1 and UGT1A2 resulted unmodified. The main effect induced by testosterone was a decrease of UGT1B1 mRNA expression in peritubular myoid cells, whereas in Sertoli cells an increase in UGT1A1 and UGT1B1 was observed. In hypoxic conditions, a reduction in UGTs mRNA levels was detected in both cell types. These findings suggest that rat UGT1 isoforms are regulated in testis by hormonal and environmental factors. Thus, it was speculated that alterations in UGTs expression and/or activity may be involved in the pathogenesis of testis injury.
Natural history of bladder cancer is characterized by high risk of disease progression even for patients with a clinical diagnosis of superficial disease; in these tumors, the occurrence of local relapse is known to be dependent on the angiogenesis rate. Basic fibroblast growth factor (bFGF), has been described to be elevated in urine and serum of patients with bladder cancer. We investigated the expression of bFGF at mRNA level in a panel of 32 transitional cell tumors of the urinary bladder and in normal bladder tissues used as controls. Expression of bFGF was found elevated in most tumors of high stage, where its presence was found correlated with the occurrence of early local relapses. Furthermore, bFGF was found highly expressed in the majority of tumors showing a high bcl-2 expression rate. Our data suggest that bFGF expression could contribute to the progression of disease; it may provide a prognostic indicator in the identification of patients with high risk for occurrence of local relapses.
Explore the source record for details and available documents.
Recent epidemiological studies suggest that the risk for urological malignancies may be related to the exposure to infectious agents. Human Papillomaviruses type 16 and 18 (HPV 16, HPV 18), Epstein-Barr virus (EBV), cytomegalovirus (CMV) and herpes simplex virus type 2 (HSV-2) have been suggested previously as cofactors in the pathogenesis of some malignancies in humans. The present paper, the presence of HPV 16, HPV 18, EBV, CMV and HSV-2 genomes was investigated in a panel of 35 biopsies from urinary bladder carcinomas using the polymerase chain reaction (PCR). Sequences of EBV, HPV, CMV and HSV-2 genomes were detected in 34%, 31%, 11% and 9% of tissue samples respectively, while in 20% of patients we found more than one viral infection. Absence of viral genomes was found in normal bladder. To our knowledge, this is the first report concerning the association of EBV, CMV and HSV-2 with bladder cancer. This finding may raise the question whether such viral infection may contribute to development and progression of some types of urological malignancies in humans.
Elevated expression of transforming growth factor-alpha (TGF-alpha) gene has been previously reported in some types of human neoplasms, but its role in the pathogenesis of bladder cancer has still not been investigated. In the present study, we analysed 28 samples of early stage bladder tumours for the presence of TGF-alpha mRNA using reverse transcription-polymerase chain reaction (RT-PCR). We detected TGF-alpha mRNA in 71% (20/28) of these samples. When we related the expression levels of TGF-alpha with local relapses of patients during a follow-up of 2 years, we found that a high TGF-alpha expression level in bladder cancer was significantly associated with local relapses in patients with early stage tumours. The appearance of early relapses in tumours with high TGF-alpha expression levels may suggest the existence of an additional marker in the prediction of local relapses in patients with superficial disease.
To determine the characteristics of the N-terminal transactivation domain (AF-1) of the mouse estrogen receptor (ER), we constructed a number of deletion mutants. Wild-type and mutant receptors were expressed in yeast cells and assayed for their ability to transactivate an estrogen-responsive reporter plasmid (ERE-CYCl-LacZ) that contained a single estrogen response element of the vitellogenin A2 gene promoter. Deletion of the N-terminal 121 amino acids from the mouse ER resulted in a 50% reduction in transactivation activity compared with the full-length wild-type ER. Deletion of the first 150 amino acids resulted in loss of 90% transactivation activity. An ER deletion mutant lacking residues 121-154 retained full transcriptional activity, suggesting that this region plays a significant transacting role only when the first portion is deleted. A point mutation was introduced in the C-terminal region at Met-521 in order to study the possible interaction between the C-terminal ligand-binding domain and the N-terminal AF-1 region. This mutant ER, M521G, exhibited 150% of the transcriptional activity of the wild-type ER. An M521G mutant lacking the N-terminal 121 amino acids retained full transactivation activity, whereas, M521G lacking 150 amino acids resulted in only 10% of wild-type activity. These results suggest that residues 121-154 might interact with the C terminus to affect transcription. In summary, multiple N-terminal regions in the ER were identified that function in transactivation. Furthermore, a point mutation in the C-terminal portion of the ER may change the conformation of the ER ligand-binding domain, producing a more stable receptor/ligand complex that increases transcriptional activity. These data suggest that the N- and C-terminal portions of the ER interact in a cooperative manner to activate transcription from target genes.
Apoptotic cell death represents an important mechanism for the precise regulation of cell numbers, and a defence mechanism against tumoral cell. bcl-2 and bax genes are known to be involved in the control of apoptotic pathways; in particular, the ratio between bcl-2 and bax represents a cell rheostat that is able to predict a cell's response toward life or death to an apoptotic stimulus. In the present study we investigated the role of bcl-2 and bax gene expression in a panel of 37 low-grade tumours of the urinary bladder, and correlated the expression of these genes to the prognosis of patients in a follow-up of more than one year. We found that levels of bax expression higher than bcl-2 in bladder tumours well correlates to a better outcome for patients. Early relapses are much more frequently observed in those patients whose tumours express more bcl-2 than bax mRNA. We conclude that the bcl-2/bax expression ratio may be considered as a marker for disease progression in low grade bladder tumours, independently of clinical staging and histological grading.
The prevalence of some sexually transmitted viruses, possibly involved in cervical carcinogenesis, was studied in the cervix of women with normal cytology. The presence of human papillomaviruses (HPV) type 16 and 18, cytomegalovirus (CMV) and Epstein-Barr virus (EBV) genomes in cervical cells taken from 143 healthy Italian women was investigated using the polymerase chain reaction (PCR). The study population was divided into four groups with respect to age as follows: group I, 17 to 25 years, n = 48 women; group II, 26 to 35 years, n = 30; group III, 36 to 50 years, n = 32; and group IV, 51 to 70 years, n = 33. In the first age group prevalence rates of HPV 16, CMV and EBV infection of 23%, 21% and 19% were found respectively. The infection rates of HPV 16 and CMV were shown to decrease with age, with prevalences of HPV 16 at 10% in the second group, 6% in the third and 3% in the fourth and of CMV at 13% in the second and third and 6% in the fourth groups. The prevalence of EBV infection did not decrease with increasing age (19% in the first and third groups, 20% in the second and 18% in the fourth). The occurrence of HPV 18 genome was very low (0-3%) and independent of age. In the first age group a higher percentage of double infections (16.6%) was found than in the three other age groups (6% in the second and third and 3% in the fourth). The finding of multiple infections in younger women requires further study in order to clarify the implications of such viral infections in healthy women and their contribution to the development of genital tract malignancies.
Explore the source record for details and available documents.
The mouse estrogen receptor (mER) exhibits ligand stereochemical specificity for indenestrol A (IA), a stilbestrol estrogen. IA has a chiral C3 methyl group, and the mER preferentially binds the S-enantiomer (IA-S), resulting in elevated biological activity when compared with the IA-R enantiomer. To elucidate the mechanisms for this stereochemical recognition, we have constructed a series of mERs with individual amino acid substitutions at Met521, His528, Met532, and Val537. The abilities of yeast-expressed wild-type and mutant mERs to transactivate an estrogen-responsive reporter gene construct were measured in the presence of diethylstilbestrol (DES) and IA enantiomers. The concentration of IA-S required to induce half-maximal transactivation by wild-type mER was 10-fold lower than IA-R, which is attributed to the 15-fold greater binding affinity for IA-S. Wild-type mER displayed similar dose-response curves for IA-R and demethyl IA, which lacks a C3 methyl group, demonstrating that the presence and correct orientation of the C3 methyl group on the IA compound is required for high-affinity ligand binding and transcriptional activity. Each mutant exhibited a reduced preference for IA-S enantiomer with respect to transactivation, suggesting that this region of the mER functions in ligand stereochemical recognition and activation. A mutation at Met532 diminished DES- and IA-S-induced transactivation by 7.5-fold and 40-fold respectively, with minimal change on their binding affinity. These data suggest that Met532 is required for transactivation induced by the potent agonist, IA-S, and the M532G mutation effectively uncouples IA-S ligand binding from transactivation. Use of these stereochemically different ligands in combination with mutagenesis of the mER demonstrates that ligand structure could influence transactivation by specifically altering the conformation of the mER AF-2 region.
Explore the source record for details and available documents.
The mouse estrogen receptor was expressed in yeast cells to study the mechanism of action of anti-estrogens. Tamoxifen and hydroxytamoxifen, estrogen antagonists in mammalian tissues, failed to antagonize estradiol-induced expression of a VitA2-ERE-CTC1-lacZ reporter gene construct and exhibited full agonist activity, while nafoxidine exhibited partial antagonism as well as partial agonism. ICI 164,384 is a potent anti-estrogen in both mouse and human estrogen receptor systems. Our previous studies in the mouse uterus indicated that rapid degradation of the estrogen receptor accounted for the loss of estrogen responsiveness. In yeast however, ICI 164,384 or an isomer ICI 182,780 were unable to antagonize estradiol at concentration of 200 microM. On the contrary, both ICI compounds exhibited partial agonist activity by stimulating beta-galactosidase activity to 50% that of estradiol. We examined the level of estrogen receptor in the yeast after treatment with estradiol, ICI 164,384 or vehicle by Western blot and found no ICI-induced reduction of estrogen receptor levels, but observed an increase in estrogen receptor following estradiol treatment. This indicates that the proteolytic activity responsible for degrading estrogen receptor in ICI 164,384-treated uteri or eukaryotic cells is not present in yeast. The agonist activity seen with ICI indicated that ICI-bound estrogen receptor is able to induce expression of an estrogen-responsive reporter gene. In support of this, estrogen receptor from ICI 164,384-treated yeast was able to bind an estrogen-responsive element in a gel-shift assay.(ABSTRACT TRUNCATED AT 250 WORDS)