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Biomedical subjects

M Derenzini

Publications and source records attributed to M Derenzini.

At least 37 records · Page 2Linked to original sources
PubMed1999

Detection of EWS chimeric transcripts by nested RT-PCR to allow reinfusion of uncontaminated peripheral blood stem cells in high-risk Ewing's tumor in childhood.

BACKGROUND AND OBJECTIVE: Ewing's tumors (ET) are primary malignancies of bone and soft tissues characterized in at least 96% of cases by specific fusion transcripts originating from recurrent chromosomal translocations. Clinical protocols for high-risk metastatic ETs include high-dose radiation/chemotherapy followed by autologous peripheral blood stem cell (PBSC) reinfusion. We used nested reverse transcriptase polymerase chain reaction (RT-PCR) to search for the presence of ET-specific transcripts in PBSC collections from patients with high-risk ET in order to collect harvests free from neoplastic cells but still sufficient to obtain early stable engraftment. DESIGN AND METHODS: Thirty-seven harvest samples from 15 ET patients treated with mobilizing chemotherapy were analyzed. Nested RT-PCR was performed to detect ET-specific transcripts in RNA extracted from the PBSC collections. RESULTS: A total of 30 harvests was performed. On average, 2 harvests (range 1-4) were sufficient to collect the minimum required number of mononuclear cells (2.5

Child↗
PubMed1998

Primary endocervical extraosseous Ewing's sarcoma/PNET.

A 36-year-old woman presented with intermenstrual spotting and was found to have a cystic mass involving the uterine cervix on a pelvic ultrasound examination. A necrotic and hemorrhagic tumor was excised by hysterectomy and processed for light and electron microscopic investigation and molecular analysis. Microscopic examination revealed a small round cell tumor that immunohistochemical studies (including staining for the highly restricted surface antigen p30/32MIC2) and ultrastructural studies indicated was an extraosseous Ewing's sarcoma (EES)/primitive neuroectodermal tumor (PNET). This diagnosis was established by detection of EWS/ERG fusion transcript through reverse transcription polymerase chain reaction (RT-PCR) with nested primers. Full body computed tomography failed to detect any extrauterine tumor, and the patient is clinically free of disease 18 months after hysterectomy. This case represents the first report of a primary EES/PNET arising in the uterine cervix.

Adult↗
PubMed1998

Hepatocyte proliferation rate is a powerful parameter for predicting hepatocellular carcinoma development in liver cirrhosis.

AIMS: A sound predictive test is lacking for the identification of cirrhotic patients at high risk of developing hepatocellular carcinoma. The present study evaluates the measurement of hepatocyte expression of silver stained nucleolar organiser region (AgNOR) proteins as a risk factor for the development of hepatocellular carcinoma in cirrhosis. METHODS: Liver biopsies from 176 cirrhotic patients included in a follow up surveillance programme for hepatocellular carcinoma development were evaluated prospectively for hepatocyte AgNOR protein quantity. The follow up programme consisted of clinical and biochemical assessment every three months, and ultrasound scanning and serum alpha-fetoprotein (alpha FP) assessment every six months. Histological sections from the needle biopsies performed at enrollment were stained selectively for AgNOR proteins and the percentage of hepatocytes with an AgNOR protein area > or = 7 micron 2, indicative of a proliferative state (AgNOR proliferation index (AgNOR-PI)), was measured. RESULTS: During the mean (SD) follow up time of 65.5 (36.29) months (range, 12-143; median, 67), hepatocellular carcinoma was diagnosed in 48 of 176 patients (27.3%). The AgNOR-PI of the whole series ranged from 0% to 5% (median, 0.9%), and was significantly higher in patients with liver cell dysplasia and hepatitis B surface antigen (HBsAg) positivity (p < 0.0001 and p = 0.0002, respectively). The 176 patients were divided into two groups according to their AgNOR-PI scores; a cut off value of 2.5% defined by the receiver operating characteristic curve and the Youden index was used. Forty two patients were included in the high AgNOR-PI (< 2.5%) group, and 134 patients the low AgNOR-PI (< 2.5%) group. In the high AgNOR-PI group, 25 of 42 patients developed hepatocellular carcinoma, in contrast to only 23 of 134 patients (17.2%) in the group with a low AgNOR-PI (p < 0.0001). Hepatocellular carcinoma development was also significantly more frequent in patients with liver cell dysplasia and HBsAg positivity. Multivariate analysis using AgNOR-PI, liver cell dysplasia, HBsAg positivity, and hepatitis C virus (HCV) infection as covariates demonstrated that the AgNOR-PI parameter was the only significant predictor of hepatocellular carcinoma development. CONCLUSIONS: These results demonstrate that a high hepatocyte proliferation rate is a major risk factor for hepatocellular carcinoma development in the cirrhotic liver. Therefore, the evaluation of the hepatocyte proliferation rate is very important to identify patients requiring a more strict follow up programme for early diagnosis of hepatocellular carcinoma.

Adult↗
PubMed1998

Growth, spread, and extracellular localization of herpes simplex virus 1 in Vero cells in the presence of an anti-gD plaque inhibiting monoclonal antibody.

Evidence for a direct cell-to-cell virus transfer could be provided by an agent that inhibits plaque formation without interfering with the processes that determine plaque growth in the exit and reinfection pathway of virus transfer. We studied the process of Vero cell infection by herpes simplex virus type 1 laboratory strain F [HSV-1 (F)] in the presence of monoclonal antibody (mAb) F10, an anti gD mAb that inhibits plaque development but does not neutralize virus infectivity in the absence of complement. In virus growth curves, cell associated virus was inhibited at low (0.01) but not at high (10) MOI when all cells are simultaneously infected, showing that the target of the mAb is the process of progressive cells recruitment and not the rate of virus replication. The mAb slightly inhibited virus exit and delayed virus entry. However these two additional inhibitory activities were not responsible for inhibition of virus spread, at least at early time of infection. In fact inhibition of virus spread, as measured by reduction of infectious centers (IC) from infected monolayers, could be appreciated before the appearance of extracellular virus in control cultures. We obtained electron microscope evidence that, both in the absence and in the presence of mAb, extracellular virus was initially concentrated at the interspaces between adjacent cell membranes, with little or no virus present at free cell surfaces. At more advanced stages of infection, only virus at free cell surfaces was found. The results of the study of virus replication in the presence of the mAb confirmed the hypothesis of the existence of a pathway of virus transfer between adjacent cells independent from extracellular virus. However, no electron microscope evidence for a direct cell-to-cell virus passage or for a modification of virus transfer brought about by the plaque inhibiting mAb was obtained. Interestingly, electron microscope studies suggested a targeting of the virions to different extracellular spaces, intercellular spaces and free cell surfaces, in intact and damaged cells respectively.

Animals↗
PubMed1998

Nucleolar function and size in cancer cells.

We have have studied the relationship between nucleolar function and size and cell doubling time in cancer cells. Seven human cancer cell lines characterized by different proliferation rates were used. Nucleolar functional activity was evaluated by measuring RNA polymerase I activity and expression of RNA polymerase I upstream binding factor (UBF), DNA topoisomerase I, and fibrillarin, three proteins involved in synthesis and processing of rRNA. Transcriptional activity of RNA polymerase I was strictly related to cell doubling time (r = -0.97; P < 0.001). The quantitative distribution of UBF, DNA topoisomerase I, and fibrillarin was evaluated on Western blots using specific monoclonal antibodies by densitometric analysis of autoradiographic signals. It was found to be directly related to RNA polymerase I transcriptional activity (r = 0.89, P = 0.008 for UBF; r = 0.95, P = 0.001 for DNA topoisomerase I; and r = 0.91, P = 0.004 for fibrillarin) and inversely related to cell doubling time (r = -0.87, P = 0.011 for UBF; r = -0.97, P < 0.001 for DNA topoisomerase I; and r = -0.91, P = 0.005 for fibrillarin). The nucleolar areas were measured by automated image analysis on toluidine blue-stained cells. The values of the stained nucleolar structures per cell were directly related to RNA polymerase I transcriptional activity (r = 0.94, P = 0.001) and inversely related to cell doubling time (r = -0.98, P < 0.001). The same area values of the nucleolar structures stained by toluidine blue were also closely related to the amount of UBF (r = 0.92, P = 0.003), DNA topoisomerase I (r = 0.98, P < 0.001), and fibrillarin (r = 0.95, P = 0.001), and to the in situ quantitative distribution of AgNOR proteins (r = 0.98, P < 0.001). Our results demonstrated that in cancer cells rRNA transcriptional activity and nucleolar size are inversely related to cell doubling time. Quantitative distribution of nucleolar structures within the cell represents a cytohistological parameter of the rapidity of cell proliferation.

Blotting, Western↗
PubMed1998

Conjugation of 5-fluoro-2'-deoxyuridine with lactosaminated poly-l-lysine to reduce extrahepatic toxicity in the treatment of hepatocarcinomas.

BACKGROUND: The hepatocyte receptor for asialoglycoproteins, which binds and internalizes galactosyl-terminating peptides, was found to be expressed also on the cells of well differentiated hepatocarcinomas. AIMS: We explored the possibility of obtaining a delivery of antiblastic drugs to hepatocarcinoma cells through this receptor. METHODS: We conjugated 5-fluoro-2'-deoxyuridine (FUDR) with lactosaminated poly-L-lysine. 5-fluoro-2'-deoxyuridine is an active drug in the treatment of solid tumours, but with toxic effects on intestine and bone marrow. Poly-L-lysine is an galactosyl-terminating carrier which enables preparation of conjugates with very high drug load. We studied the pharmacological activity of poly-L-lysine-5-fluoro-2'-deoxyuridine conjugate on in vitro proliferation of Hep G2 cells, a human hepatocarcinoma cell line. Moreover, we compared the levels of radioactivity in liver, intestine and heart of mice injected with free or conjugated [3H]5-fluoro-2'-deoxyuridine. RESULTS: We found that poly-L-lysine-5-fluoro-2'-deoxyuridine enters into Hep G2 cells through the asialoglycoprotein receptor and, after intracellular penetration, releases the drug in a pharmacologically active form. Administered to mice, the conjugate leads to enhanced accumulation of the drug in liver versus the intestine and the heart. CONCLUSIONS: These data support conjugation with poly-L-lysine as a way to obtain drug targeting to those hepatocellular carcinomas which maintain the asialoglycoprotein receptor.

Amino Sugars↗
PubMed1997

N-myc amplification and cell proliferation rate in human neuroblastoma.

In neuroblastoma, N-myc amplification has been found to be strikingly associated with rapid tumour progression and poor prognosis. Recent studies have demonstrated that cell proliferative activity also significantly predicts the clinical outcome in patients with neuroblastoma. In order to define the correlation between N-myc amplification and cell proliferation rate, in the present investigation the two parameters were first assessed in 48 neuroblastoma tumours. N-myc amplification was evaluated in frozen specimens by Southern-blot analysis using the NB 19-21 probe and it was detected in nine patients. Cell proliferative activity was determined by measuring the AgNOR protein area in histological sections selectively stained by silver. The mean AgNOR protein area value of neuroblastomas with N-myc amplification (3.63 +/- 1.62 microns2) was not significantly different from that of neuroblastomas without N-myc amplification (2.46 +/- 1.57 microns2; P = 0.30). On the other hand, both N-myc amplification and AgNOR protein expression were found to be significantly related to the clinical outcome of the disease (P < 0.001 and P = 0.0143, respectively; median follow-up time = 47 months; range 18-106 months). In a second set of experiments, the relationship between N-myc amplification and cell proliferation rate was assessed in seven established human neuroblastoma cell lines. N-myc amplification was found to be completely independent of the population doubling time (DT), which, on the contrary, was strictly related to the quantitative expression of AgNOR protein (r = -0.947; P < 0.001). Altogether, the present results indicate that N-myc amplification and cell proliferation rate are not interrelated in neuroblastoma, each representing an independent biological parameter of cancer cells associated with the clinical behaviour of the disease.

Antigens, Nuclear↗
PubMed1997

AgNOR protein quantity of cervical smears correlates with that of histological sections in cervical intraepithelial neoplasia.

The quantitative distribution of AgNOR proteins has been determined by image cytometry in 52 cervical smears obtained from normal cervix (n = 20), grade I CIN (cervical intraepithelial neoplasia) (n = 3), grade II CIN (n = 5) and grade III CIN (n = 24). No significant difference was demonstrated in the mean AgNOR protein area values between normal cervix, CIN I and CIN II, while AgNOR protein scores of CIN III were significantly greater than those of normal cervix (p < 0.05). AgNOR protein quantity was also determined in 17 colposcopic directed biopsies of patients with CIN lesions (3 CIN II and 14 CIN III) already studied by cytological analysis. When AgNOR protein values of histological sections and corresponding cytological smears were compared by linear regression analysis, a significant correlation was found (r = 0.74, p < 0.05). Our results demonstrate that AgNOR protein quantity of cervical smears actually reflects that of the cervical epithelium in situ and may therefore be useful for the cytological diagnosis of cervical lesions.

Biopsy↗
PubMed1996

Chromosome 1 aneusomy with 1p36 under-representation is related to histologic grade, DNA aneuploidy, high c-erb B-2 and loss of bcl-2 expression in ductal breast carcinoma.

Chromosome 1 abnormalities with loss of 1p36 have been investigated in 95 breast-cancer samples by means of a dual-target fluorescence in-situ hybridization (FISH) technique using the pUC 1.77 and p1-79 probes, specific for the 1q12 and 1p36 regions, respectively. Abnormalities for one or both probes were detected in 83/95 samples. Relative 1p36 under-representation was found in 79/95. The clinical relevance of these alterations was studied by comparing the FISH results with several parameters currently used in breast-cancer pathology. Distinct patterns of chromosome 1 abnormalities were found among the histologic types of breast carcinoma. Lobular or mucinous samples showed few or no alterations, whereas most ductal samples had high chromosome 1 polysomy with under-representation of 1p36. In ductal carcinomas, chromosome 1 alterations increased with histologic grade, DNA aneuploidy, loss of bcl-2 and high c-erb B-2 expression. These associations were found to be statistically significant. No correlation between chromosome 1 alterations and nuclear grade, age, size, lymph-node involvement, hormonal receptor presence, proliferation activity or p53 protein expression was detected. These results indicate the utility of this FISH technique for a better definition of the biological characteristics of ductal carcinomas.

Adult↗
PubMed1996

Qualitative and quantitative analysis of AgNOR proteins in chemically induced rat liver carcinogenesis.

A qualitative and quantitative analysis of silver-stained nuclear organizer regions (AgNOR) proteins was performed during hepatocarcinogenesis induced in rats initiated by diethylnitrosamine (DENA) using the resistant-hepatocyte model. Nuclear proteins from control hepatocytes, hyperplastic nodules, and hepatocellular carcinomas (HCC) separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were transferred to nitrocellulose membranes and specifically silver-stained for AgNOR proteins. No difference was observed in the distribution pattern of the silver-stained bands among control, hyperplastic, or cancer cells. The same was true if human cirrhosis and HCC were compared. The evaluation of individual AgNOR protein amounts by computerized densitometric analysis showed that 1) the integrated optical density value of the total AgNOR proteins was greatest in cancer cells, lesser in hyperplastic hepatocytes, and lowest in control hepatocytes, and 2) the amount of the two major silver-stained proteins, nucleolin (105 kd) and protein B23 (39 kd), was always a constant percentage of total AgNOR proteins. An experiment using bromodeoxyuridine incorporation showed that, during hepatocarcinogenesis, AgNOR protein quantity progressively increased and was significantly related to the increased hepatocyte labeling index. These results show that AgNOR protein distribution changes during hepatocarcinogenesis are caused neither by the synthesis of new AgNOR proteins nor by an unbalanced synthesis of individual AgNOR proteins, but to an increased synthesis of nucleolin and protein B23, which is associated with a progressive increased hepatocyte proliferation rate.

Animals↗
PubMed1996

Enzymatic cytochemistry, DNA ploidy and AgNOR quantitation in hepatocellular nodules of uncertain malignant potential in liver cirrhosis.

Conventional histological examination of echo-guided biopsy specimens can be inconclusive in small nodular lesions in cirrhotic livers. We investigated the diagnostic potential of cytochemical analysis of dipeptidyl-peptidase IV (DPP IV), of image analysis of nuclear DNA content, and of interphase silver-stained nucleolar organizer regions (AgNORs) in 12 cases of small (13- to 29-mm in diameter) hepatic nodules visualized in cirrhotic patients by ultrasonography. All cases underwent an echo-guided liver biopsy at the time of detection and in none of them were histological signs of malignancy found. Characterization with the above-mentioned techniques was always done at the time of histological examination. These patients underwent a mean (+/- SD) follow-up of 27.0 (+/- 11.2) months after biopsy, with repeated ultrasound (US) examinations. In the seven patients with subsequent neoplastic growth, DPP IV score was altered in five of six; the fraction of mononucleated polyploid cells was altered in six of seven; and the AgNOR quantity exceeded the cutoff value of 4 microns2 in five of five cases. Among the five lesions whose US appearance remained unchanged during the follow-up, only one abnormality (AgNORs) was found in one case. The combined cytochemical analysis of DPP IV, nuclear DNA content, and quantitative evaluation of interphase AgNORs in biopsy samples may contribute to the differential diagnosis of hepatocellular nodules of uncertain type in the cirrhotic liver.

Biopsy↗
PubMed1996

In hepatocellular carcinoma AgNOR protein expression correlates with tumour mass doubling time.

AIMS/METHODS: The relationship between AgNOR protein expression and doubling time was evaluated in 20 untreated nodules of hepatocellular carcinoma arising in cirrhotic liver. AgNOR protein quantity within the lesion was defined by image cytometry on histological sections from frozen biopsies obtained under ultrasound-guidance, selectively stained for AgNOR proteins. Tumour doubling time was calculated 6 months after diagnosis by measuring the volume variations of the nodules over a fixed period by "real time" ultrasonography. RESULTS: The doubling time of nodules characterized by high AgNOR protein area values (> 5.50 microns2, corresponding to the median AgNOR protein value) was shorter than that of nodules with low AgNOR protein area values (< 5.50 microns2). A highly significant difference in the mean doubling time values between the two groups (6.31 +/- 2.68 (E.S.) versus 15.92 +/- 3.03 (E.S.) months, respectively; p = 0.009) was found. Moreover, when the relationship between AgNOR protein and doubling time values was tested by linear regression analysis, a significant inverse correlation was observed (r = -0.68; p < 0.005). CONCLUSIONS: Our results indicate that AgNOR protein quantity represents a reliable parameter for predicting the tumour growth rate of untreated hepatocellular carcinoma nodules. Among the procedures commonly employed for the assessment of cell proliferation, the evaluation of the AgNOR parameter seems to be particularly suitable for kinetic analysis of ultrasound-guided fine-needle liver biopsies.

Adult↗