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M Boiocchi

Publications and source records attributed to M Boiocchi.

At least 37 records · Page 2Linked to original sources
PubMed2000

Coordinated expression and amplification of the MDM2, CDK4, and HMGI-C genes in atypical lipomatous tumours.

Atypical lipomatous tumours (ALTs) represent a distinctive subset of mesenchymal neoplasms featuring mature adipocytic differentiation. Most ALTs are characterized cytogenetically by the presence of supernumerary ring and/or long marker chromosomes derived from the chromosomal region 12q13-15. The 12q13-15 chromosome region contains several genes which may play an important role in human tumorigenesis. A series of ALTs was analysed by investigating the MDM2, CDK4, and HMGI-C genes and their proteins. The study was extended to a series of ordinary lipomas, to determine whether the immunohistochemical investigation of these gene products might play any diagnostic role. Cytogenetic analysis revealed the presence of various cytogenetic aberrations involving the 12q13-15 region in 11/18 (61%) lipomas and of ring chromosomes in all ALTs. Overexpression of mdm2 protein was observed in 6/12 (50%) atypical lipomatous tumours. All lipomas were mdm2-negative. cdk4 overexpression was present in 100% of ALTs. Weak cdk4 immunopositivity was detected in 2/18 (11%) ordinary lipomas in a minority of cells. HMGI-C immunopositivity was observed in 10/12 (83%) ALTs. Positive immunoreactivity was also observed in 8/18 (44%) lipomas. Southern blot analysis revealed amplification of the CDK4 and MDM2 genes in 3/5 ALTs analysed. HMGI-C was amplified in 3/5 cases and was deleted in one case. Mutation analysis of the CDK4 gene did not demonstrate any mutation. These data support the hypothesis that ordinary lipomas may form a molecular genetic and morphological continuum with ALT. At one end of the spectrum are lipomas characterized by 12q13-15 rearrangements and HMGI-C activation and at the other end are ALTs with ring chromosomes, 12q13-15 amplification with overrepresentation of the HMGI-C, CDK4 or MDM2 genes, and aberrant cdk4, mdm2, and HMGI-C protein expression. These findings not only provide insights into the molecular pathogenesis of lipomatous tumours, but also indicate that the immunohistochemical analysis of mdm2 and cdk4 may help to increase diagnostic accuracy.

Adult↗
PubMed2000

Oligoclonal non-neoplastic B cell expansion is the key feature of type II mixed cryoglobulinemia: clinical and molecular findings do not support a bone marrow pathologic diagnosis of indolent B cell lymphoma.

OBJECTIVE: Type II mixed cryoglobulinemia (type II MC) is often characterized by features of indolent B cell lymphoma (IBCL) found on pathologic examination of bone marrow, whereas the clinical evidence does not indicate a neoplastic disorder. To better address the issue of indolent malignant versus nonmalignant bone marrow lymphoproliferation underlying type II MC, molecular analyses of B cell clonality were performed in the present study, in conjunction with clinical and pathologic characterization. METHODS: Polymerase chain reaction DNA amplification of immunoglobulin heavy chain genes was performed in bone marrow biopsy specimens obtained from 15 selected patients with type II MC, all infected with hepatitis C virus. Five of them had also developed overt B cell lymphoma (OBCL) during followup. Bone marrow features were consistent with IBCL in 9 of the 15 patients (group 1) and with reactive lymphoplasmacytosis in 6 of the 15 (group 2). RESULTS: An oligoclonal B cell expansion was detected in 6 of 9 baseline bone marrow lesions from group 1 patients (biclonal or monoclonal expansion in the remaining 3 cases), and in 6 of 6 from group 2 patients. OBCL was always monoclonal. Selected lesions were analyzed by clonospecific hybridization and by cloning and sequence analysis in patients who had developed OBCL at followup. In 4 of 5 cases, OBCL did not originate from the dominant B cell clones that were overexpanded in the putative neoplastic baseline bone marrow lesions. OBCL clones showed significant homology with rheumatoid factor database sequences. CONCLUSION: Based on the present results, as well as on evidence from previous studies of liver lesions, oligoclonal non-neoplastic B cell proliferation in the course of chronic infection-related inflammation appears to be the key feature of type II MC. Of note, molecular evidence from target tissues supports the clinical findings both at the time of type II MC diagnosis and in cases of OBCL complication. Bone marrow pathologic findings resembling those of IBCL should thus be considered in the light of clinical and molecular evidence.

Adult↗
PubMed2000

Gastric mucosa as an additional extrahepatic localization of hepatitis C virus: viral detection in gastric low-grade lymphoma associated with autoimmune disease and in chronic gastritis.

The hepatitis C virus (HCV) has been linked to B-cell lymphoproliferation and autoimmunity, and has been localized in several tissues. The clinical observation of an HCV-infected patient with Sjögren's syndrome (SS) and Helicobacter pylori (HP) positive gastric low-grade B-cell non-Hodgkin's lymphoma (NHL), which did not regress after HP eradication, led us to investigate the possible localization of HVC in the gastric microenvironment. HCV genome and antigens were searched in gastric biopsy specimens from the previously mentioned case, as well as from 9 additional HCV-infected patients (8 with chronic gastritis and 1 with gastric low-grade B-cell NHL). HCV-specific polymerase chain reaction (PCR) and immunohistochemistry procedures were used. The gastric B-cell NHL from the patient with SS was characterized by molecular analyses of B-cell clonality. HCV RNA was detected in both the gastric low-grade B-cell NHL and in 3 out of 6 gastric samples from the remaining cases. HCV antigens were detected in the residual glandular cells within the gastric B-cell NHL lesions, in glandular cells from 2 of the 3 additional gastric lesions that were HCV positive by PCR, and in 1 additional chronic gastritis sample in which HCV-RNA studies could not be performed. By molecular analyses, of immunoglobulin genes, the B-cell NHL from the patient with SS was confirmed to be a primary gastric lymphoma, subjected to ongoing antigenic stimulation and showing a significant similarity with rheumatoid factor (RF) and anti-HCV- antibody sequences. Our results show that HCV can localize in the gastric mucosa.

Aged↗
PubMed2000

Dose-finding and pharmacologic study of chronic oral idarubicin therapy in metastatic breast cancer patients.

Oral idarubicin (IDA) is an active drug in metastatic breast cancer, but its role in the management of this tumor is yet not established completely. To investigate a new modality of IDA administration, a dose-finding study was designed with hyperfractionated doses. The purpose was to determine the maximum tolerated dose (MTD), the dose-limiting toxicity (DLT), and the pharmacokinetics of this schedule. IDA was administered twice daily as outpatient therapy in cycles of 3 weeks followed by a 1-week rest. Thirty-one patients with progressive metastatic breast cancer and pretreated with chemotherapy (including epirubicin and doxorubicin) were enrolled. DLT was defined as G4 hematological toxicity or any other toxicity G3 or higher (Bloom and Richardson grading). Inter- and intrapatient dose increases were studied. Pharmacokinetics of IDA and its metabolite idarubicinol (IDOL) were evaluated. IDA dose was increased from 2 mg/day to 10 mg/day, by steps of 1 mg/day, with the larger dose given in the evening. MTD was reached at 10 mg/day. Overall, the therapy cycles were 69 (median/patient, 2; range, 1-6). DLTs were G4 neutropenia associated with leukopenia and thrombocytopenia in one patient and G3 diarrhea in another of the 5 patients in the 10 mg/day cohort. The two patients developing DLT at the daily dose of 10 mg received a dose normalized for body surface of 6.85 and 5.65 mg/m2/day, respectively. We considered 5.5 mg/m2/day to be the MTD. Other toxicities were nausea, vomiting, neutropenia, and diarrhea, grades G1 to G2. By univariate analysis, significant correlations were observed between absolute neutrophil count at nadir and IDA area under the curve (P = 0.022; r = -0.33), IDA Cmax (P = 0.0067; r = -0.38), IDOL area under the curve (P = 0.0009; r = -0.43), and IDOL Cmax (P = 0.0016; r = -0.41), respectively. By multivariate analysis, IDA Cmax was the strongest determinant for neutropenia (R2 = 0.14; P = 0.01). Among the 21 patients evaluable for response, 3 (14.3%) had partial response (lasting 3, 6, and 8 months, respectively), and 6 (28.6%) had a complete arrest of disease progression (lasting 2-6 months). In conclusion, the MTD of this schedule is 10 mg/day and the DLTs are neutropenia and diarrhea. Tolerance was good, and the treatment is feasible as home therapy. Some objective measurable responses were documented in this group of anthracycline-pretreated patients. IDOL could have a role for the pharmacological effect. Further evaluation of this schedule is warranted to assess the activity and toxicity of prolonged oral IDA administration.

Administration, Oral↗
PubMed1999

BRCA1 and BRCA2 genes: role in hereditary breast and ovarian cancer in Italy.

The heritable defects of BRCA1 and BRCA2 genes have been shown to predispose to breast and ovarian cancers. In a previous report, we analyzed 46 Italian families with breast and/or ovarian cancer for BRCA1 mutations. In the present study, those families and 11 others were screened for BRCA2 mutations; the newly enrolled families were also analyzed for the BRCA1 gene. The coding region and splice boundaries of BRCA2 and BRCA1 genes were assessed by the protein-truncation test and single-strand conformational polymorphism. A total of 20 different mutations were found in 21 families (37%). A total of 9 families (16%) showed mutations in the BRCA1 gene, including the one new mutation identified in this study (5382insC), and 12 families (21%) presented mutations in the BRCA2 gene. BRCA2-mutated families presented breast and ovarian cancers or breast cancers only, whereas most BRCA1-mutated families presented ovarian cancer alone or in association with breast cancer. All the BRCA2 mutations led to a truncated protein: 6 were frameshift mutations, 4 were non-sense mutations and 2 involved the intronic invariant region leading to splice variants. Therefore, in the Italian population, the cumulative proportion of BRCA1 and BRCA2 mutations was within the range observed in other studies (37%), with higher involvement of BRCA2 than of BRCA1. Many families in which no mutations were found presented a very high incidence of breast and/or ovarian cancer. Among the 36 BRCA1 and BRCA2 wild-type families, 24 presented at least 4 cancer cases, indicating the existence of other important predisposing genes.

Adult↗
PubMed1999

Loss of heterozygosity at 10q in tumors of the upper respiratory tract is associated with poor prognosis.

Frequent loss of a specific chromosomic region in cancers is often associated with inactivation of a tumor-suppressor gene. The long arm of chromosome 10 is deleted in several types of tumor, among them squamous-cell carcinomas of the head and neck (HNSCC). To determine the role of 10q deletions in the tumorigenesis of the upper respiratory tract, 47 HNSCCs were examined for loss of heterozygosity (LOH) at 10q: 43% of the cases analyzed showed LOH at 10q, and 2 distinct hot spots of deletion were identified, at 10q22-23 and 10q25-26. The possible involvement of pTEN/MMAC1, a tumor-suppressor gene mapped at 10q23, was also evaluated. No mutation, homozygous deletion or loss of expression of pTEN/MMAC1 was detected, indicating that inactivation of this gene plays a minor role in HNSCC development. Interestingly, the frequency of deletion at 10q was greater in invasive carcinoma than in adjacent carcinoma in situ, and a significant association between LOH and poor prognosis was observed. Taken together, our results suggest the presence in the long arm of chromosome 10 of (a) tumor-suppressor gene(s) other than pTEN/MMAC1 and presumably involved in the malignant progression of tumors of the upper respiratory tract. Int. J. Cancer (Pred. Oncol.) 84:432-436, 1999.

Blotting, Southern↗
PubMed1999

Biologically relevant phenotypic changes and enhanced growth properties induced in B lymphocytes by an EBV strain derived from a histologically aggressive Hodgkin's disease.

Epstein-Barr virus (EBV) isolates show a wide genomic heterogeneity, and a key issue is whether distinct strain variations may contribute to the development and/or malignancy of EBV-related disorders. Herein, we report on the virologic and biologic characterization of an EBV strain derived from a cyto-histologically aggressive EBV-related Hodgkin's disease (HD) (case HD-3) showing a high number of "anaplastic" Reed-Sternberg cells expressing markedly high levels of CD30, CD40 and LMP-1. The HD-3-derived EBV showed strong in vitro immortalizing properties, as suggested by the unusually high number of spontaneous lymphoblastoid cell lines (LCLs) obtained from the patient. Immunofluorescence and immuno-cytochemical analyses showed that HD-3 LCLs expressed significantly higher levels of CD23, CD30, CD38, CD39, CD40 and CD71 antigens and CD54 and CD58 adhesion molecules than B95.8 LCLs. In contrast, the expression of CD11a, CD24, CD95, bcl-2, LMP-1 and EBNA-2 was similar in both groups of LCLs. These phenotypic changes are consistent with the induction of a pronounced activation status and are not dependent on the cellular background, having been closely reproduced by the same virus in LCLs from an unrelated donor (DEN-HD-3 LCLs). HD-3 LCLs were able to grow in vitro at low serum concentrations (up to 0.1%) and were significantly more clonogenic in soft agarose than B95.8 LCLs. Moreover, although no evidence of tumor formation was observed in nude mice injected with B95.8 LCLs, all 5 spontaneous LCLs of patient HD-3 and the 2 DEN-HD-3 LCLs grew in transplanted animals as lymphoproliferations composed of EBER+, LMP-1+ cells. Our findings indicate that the biologic properties of the HD-3 EBV strain are significantly different from those of the B95.8 virus and may have contributed to the cytologic and histo-pathologic malignancy of this HD case. Moreover, molecular characterization of the HD-3 EBV genome identified a 63-bp deletion within the 3' end of the LMP-1 gene as a likely significant change that may be responsible, at least in part, for the biologically relevant phenotypic modifications and enhanced in vitro and in vivo growth potential induced in B lymphocytes by this virus strain.

Animals↗
PubMed1999

Pharmacokinetics of oral etoposide in patients with hepatocellular carcinoma.

Etoposide dosage in patients with liver dysfunction remains controversial. Since etoposide has a hepatic component to its clearance (CL) and shows a high degree of protein binding, hepatic impairment could affect etoposide disposition. However, the empiric recommendation that the dose of etoposide be decreased in such patients may reduce systemic exposure and be detrimental to its antitumor activity. To address these issues we studied the pharmacokinetics (PK) of etoposide in patients with hepatocellular carcinoma (HCC) and underlying cirrhosis (n = 17) treated with daily oral etoposide. Unbound etoposide was obtained by ultrafiltration. Etoposide concentrations (total and free drug) were measured by high-performance liquid chromatography (HPLC) and analyzed by noncompartmental equations. The patients had mild or moderate liver dysfunction. Albuminemia was in the normal range for all the patients. Creatininemia was normal in all but two patients. PK results (mean and range) showed that etoposide disposition was unchanged in patients with liver dysfunction. We found slightly high etoposide bioavailability [F, 61% (17-95%)] and clearance [CL, 1.1 (0.7-2.3)l h(-1) m(-2)] resulting in a normal degree of systemic exposure (AUC(oral) 27 microg h ml(-1)). Normal protein binding [PB 93.2% (84.4-98.1%)] contributed to a normal level of exposure to free drug (AUC(f, oral) 1.9 microg h ml(-1)). The distribution volume [V(SS) 8.4 (6.1-13.2) l/m2] and the effective half-life [t1/2eff, 5.1 (3.0-9.6) h] were normal. Median CL and protein binding did not differ in the seven patients with total bilirubin value of > 1.2 mg/dl as compared with the ten patients with total bilirubin levels of < or = 1.2 mg/dl (1.3 versus 1.01 h(-1) m(-2) and 92.5% versus 93.4%, respectively). In agreement with this PK finding, we observed no clinical evidence of increased toxicity in patients with hyperbilirubinemia as compared with patients with normal bilirubinemia (mean WBC decrease 38% versus 47%). The only case of severe (grade 4) hematological toxicity was observed in one patient with reduced glomerular filtration. Since the pharmacological effects of etoposide correlate with the level of systemic exposure to the free drug, our data suggest that no dose reduction is needed in patients with HCC. It is even possible to increase the dose intensity in patients with favorable PK parameters under appropriate hematological and therapeutic drug monitoring.

Administration, Oral↗
PubMed1999

Activation of infiltrating cytotoxic T lymphocytes and lymphoma cell apoptotic rates in gastric MALT lymphomas. Differences between high-grade and low-grade cases.

In this study, we have characterized infiltrating T lymphocytes from 13 low-grade and 17 high-grade primary gastric MALT lymphomas by immunohistochemistry, with particular regard to the presence, activation, and topographic distribution of cytotoxic effectors. Although the prevalence of CD4+ and CD8+ cells was similar in low- and high-grade lymphomas, higher numbers of TIA-1+ cytotoxic effectors were found in this latter group of cases (11.6 versus 7. 8%; P = 0.004). Activation of CD8+ cytotoxic T lymphocytes (CTLs) was significantly more pronounced in high- than in low-grade lymphomas, as shown by immunostaining for perforin (8.7 versus 4.0%; P = 0.001) and granzyme-B (GrB) (8.7% versus 3.0%; P < 0.0001). Of note, CD20/GrB double labeling showed that high-grade lymphomas carried a markedly higher content (about ninefold) of activated CTLs relative to the number of CD20+ lymphoma B cells (0.081 +/- 0.076 versus 0.009 +/- 0.011; P < 0.0001). Moreover, high-grade lymphomas showed significantly increased apoptotic rates compared to low-grade cases (5.3 and 1.1% of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, respectively; P < 0.0001). In the whole series, the percentage of GrB+ cells and the GrB+/CD20+ ratio showed a strong linear correlation with the number of TUNEL-labeled cells. These findings, together with the frequent colocalization of CTLs and TUNEL+ neoplastic cells, suggested that apoptotic death of lymphoma cells may be due at least in part to the killing by cytotoxic effectors. Our results are consistent with the occurrence of host antitumor cell-mediated immune responses in gastric MALT lymphomas. Moreover, the finding of stronger cytotoxic responses in high- than in low-grade cases is of potential usefulness in the design of more effective therapeutic strategies for the management of these disorders.

Antigens, CD20↗
PubMed1999

High prevalence of activated intraepithelial cytotoxic T lymphocytes and increased neoplastic cell apoptosis in colorectal carcinomas with microsatellite instability.

Microsatellite instability (MSI) characterizes colorectal carcinomas (CRCs) in hereditary nonpolyposis colorectal cancer (HNPCC) syndrome and a proportion of sporadic CRCs. These MSI+ CRCs share several clinicopathological features, including a reputation for better survival rates than MSI- cases and a pronounced stromal inflammatory reaction of still undefined nature. In the present study, the presence, spatial distribution, and activation status of infiltrating cytotoxic effectors were investigated comparatively in 18 MSI+ and 37 MSI- CRCs by immunohistochemistry. The frequency of apoptosis was also evaluated by morphology and in situ end-labeling. MSI+ cases carried significantly higher numbers of cytotoxic lymphocytes infiltrating within neoplastic epithelial structures, as shown by immunostaining for CD3 (15.1 +/- 6.2 versus 4.6 +/- 4.1, P < 0.001), CD8 (13 +/- 6.4 versus 3.7 +/- 3.8, P < 0.001), and TIA-1 (11.2 +/- 6.5 versus 1.9 +/- 1.7, P < 0.001). These cytotoxic effectors were globally more activated in MSI+ than in MSI- tumors, as revealed by the expression of granzyme B (5.3 +/- 4.5 versus 0.6 +/- 1.3, P < 0.001). In MSI+ CRCs, the number of intraepithelial activated cytotoxic lymphocytes was significantly correlated with the proximal location of the tumor, a poorly differentiated phenotype, and the presence of peritumor lymphoid nodules. Multivariate analysis revealed that MSI was the major determinant of the presence of activated cytotoxic intraepithelial lymphocytes. Moreover, MSI+ CRCs also showed a significantly higher percentage of tumor cells undergoing apoptotic cell death (4.1 +/- 2.1 versus 2.6 +/- 1.1, P < 0.0001, by the TUNEL method), often located in close proximity of activated cytotoxic lymphocytes. These results are consistent with the presence of anti-tumor cytotoxic immune responses in most of MSI+ CRCs, a phenomenon that may at least in part contribute to the survival advantage ascribed to these patients.

Adult↗
PubMed1999

Evaluation of the replication error phenotype in relation to molecular and clinicopathological features in hereditary and early onset colorectal cancer.

Mutations affecting human mismatch repair (MMR) genes (MLH1, MSH2, PMS1, PMS2, and MSH6) cause tumour predisposition in hereditary nonpolyposis colorectal cancer (HNPCC) syndrome, and an association has been demonstrated with the replication error (RER) phenotype in most colorectal and some extracolonic neoplasms. A pathogenetic model for RER+ tumours through inactivation of suppressor genes has been hypothesised, and TGF beta RII, BAX and IGFIIR genes have recently been proposed as targets of such inactivating mutations. In this study, a series of 47 tumours developed in patients with known MLH1/MSH2 status and a family history of HNPCC and/or early onset colorectal cancer were characterised for the RER phenotype through microsatellite analysis. The RER phenotype, displayed by 17 tumours, was then correlated with the presence of insertions/deletions at the TGF beta RII, IGFIIR and BAX gene stretches, confirming that the TGF beta RII inactivation may be particularly critical for the RER-associated tumorigenesis. RER+ colorectal cancers (CRCs) developed more frequently in patients from HNPCC families (72.7%) than in those from families not fulfilling the Amsterdam criteria (33.3% in suspected HNPCC and 20.8% in early onset CRC patients). A consistent fraction of either Amsterdam and non-Amsterdam patients developed RER- CRCs, pointing to the involvement of other genes not related to the MMR system. The RER phenotype was associated with younger age at diagnosis in familial cases, and there was a trend for an association with proximal CRC localisation and early Dukes' stages. The RER status was also correlated with the presence and type of MLH1 and MSH2 alteration.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Effect of cyclosporin A on protein binding of teniposide in cancer patients.

We investigated the effect of cyclosporin A (CSA) on protein binding of teniposide (VM26) in 16 patients with metastatic renal cell carcinoma receiving i.v. VM26 alone over 24 h (total dose, 200 mg/m2) and in association with CSA (5 mg/kg/2 h followed by 30 mg/kg/48 h i.v.). CSA was used in an attempt to overcome multidrug resistance. The unbound fraction (%fu) of VM26 was significantly (p=0.04) higher in the cycles with CSA (median 0.8; range 0.4-1.9) than in the cycles with VM26 alone (median 0.5; range 0.1-1.6). Both total VM26 area under curve concentration (AUC0-infinity) and free VM26 AUC0-infinity increased after treatment with CSA, but the median increase in free AUC0-infinity was higher (2.7-fold) than total AUC0-infinity (1.5-fold) (p = 0.04). Bilirubin was significantly (p<0.01) increased after CSA but no association was observed between bilirubin level and %fu of VM26. Albumin was in the normal range after both VM26 alone and VM26 plus CSA. The nadir of absolute neutrophil count (ANC) after VM26 plus CSA (median 700/microl, range <100-2860/microl) was lower than after VM26 alone (median 1900/microl, range 200-6000/microl) (p = 0.0007). The median percentage of ANC compared to the pretreatment value (ANC nadir/ANC pretreatment x 100) was 39.0% (range 3.1-98.8%) in the cycles with VM26 alone and 16.9% (range 1.4-97.9%) (p = 0.007) after VM26 plus CSA. Percentage change of neutrophils significantly correlated with free AUC0-infinity VM26 in the cycles with VM26 alone and VM26 plus CSA (p = 0.04, r = -0.53 and p = 0.04, r = -0.52, respectively). Only a trend which failed to reach significance was observed between total AUC0-infinity VM26 and percentage change of neutrophils in the cycles with VM26 alone and in association with CSA (p = NS, r = -0.33 and p = 0.055, r = -0.49, respectively). In conclusion, patients treated with CSA had higher systemic exposure to unbound VM26.

Adult↗
PubMed1999

Pharmacokinetic interaction between etoposide and tamoxifen in patients with hepatocellular carcinoma.

The effect of tamoxifen (TAM) on the pharmacokinetics of oral administration of etoposide (VP-16) in patients with nonoperable hepatocellular carcinoma was investigated. The pharmacokinetics of VP-16 was studied by using a validated limited sampling strategy. The pharmacokinetic parameters of VP-16, such as area under curve (AUC), free AUC and protein binding, were determined from drug plasma concentrations at 1 and 4 h after VP-16 administration on the first day (day -1) and at the end of the chemotherapy cycle (day -21) for VP-16 alone and VP-16+TAM, respectively. When VP-16 was administered in association with TAM, the median total systemic exposure was not significantly (p = NS) different from that observed when VP-16 was administered alone [33.74 (range 11.19-56.58) versus 32.97 (range 20.23-119.28) mg/l/h]. Moreover, TAM did not affect significantly (p = NS) the levels of protein binding of VP-16 [median 94.6 (range 87.7-98.2) versus median 94.9 (range 91.6-98.0)% for VP-16+TAM and VP-16 alone, respectively] and the systemic exposure of the free drug (free AUC) [1.86 (range 0.21-4.57) versus median 1.78 (range 0.59-3.73) mg/l/h for VP-16+TAM and VP = 16 alone, respectively]. These results indicate a lack of pharmacokinetic interaction between VP-16 and TAM, and suggest that the increased hematological toxicity observed when TAM is given in combination with VP-16 could be related to pharmacodynamic interactions.

Aged↗
PubMed1999

Pharmacokinetic and pharmacodynamic effects of high-dose continuous intravenous verapamil infusion: clinical experience in the intensive care unit.

OBJECTIVE: Our study aimed at evaluating the pharmacokinetic, cardiovascular, and metabolic effects of high-dose verapamil continuous intravenous infusion in cancer patients. DESIGN: Prospective clinical and pharmacokinetic study. SETTING: Intensive care unit of a Cancer Research Institute. PATIENTS: Nine patients (age range 31 to 57 yrs) with progressive cancer disease and without cardiovascular, renal, or hepatic dysfunctions. INTERVENTIONS: After a loading dose (0.15 mg/kg followed by 12 hrs of continuous intravenous infusion at 0.20 mg/kg/hr), the infusion rate of verapamil was increased every 24 hrs (0.25, 0.30, 0.35, and 0.40 mg/kg/hr). The highest rate was maintained for 48 hrs. Doxorubicin was given from the 60 th to the 108 th hr. Hydrochlorothiazide (25 mg/day) and potassium (36 mmol/day) were given orally. Altogether, 17 courses were completed. MEASUREMENTS AND MAIN RESULTS: Steady state concentration (C(SS) and systemic clearance of verapamil and nor-verapamil (active metabolite) for each infusion rate were calculated. Mean arterial pressure (MAP), central venous pressure (CVP), heart rate (HR), PR, QT and QTc intervals, and left ventricular ejection fraction (LVEF) were measured, as well as daily body weight, blood glucose and potassium. C(SS) of verapamil and nor-verapamil increased more than proportionally to the infusion rate (p<.001). Systemic clearance of verapamil decreased over the range of the infusion rate (p<.005). MAP and HR decreased at the 12th hr (p<.001) and then plateaued. CVP increased (p<.01). The relationship between MAP, HR, CVP, and verapamil plasma concentrations was significant (r2 = .25, .14, and .35, respectively; p<.0001). LVEF did not change. Six patients (11 courses) developed junctional rhythm. Three patients (six courses) showed a PR interval increase (p<.05). Patients with junctional rhythm had higher Css of verapamil (p<.009). Overall, QT and QTc intervals increased (p<.01). A linear relationship was observed between verapamil plasma concentrations and QT intervals (r2 = .09, p<.01). Cardiovascular side effects did not determine treatment withdrawal in any patient. Body weight, blood glucose, and potassium did not show significant changes. CONCLUSIONS: Our data suggest a capacity-limited clearance of high-dose verapamil. In the absence of heart disease, following a step by step increase of the dosage, the high plasma verapamil concentrations (617 to 2970 ng/mL) produce frequent but well tolerated hemodynamic and electrocardiogram changes.

Adult↗
PubMed1999

Hereditary colorectal cancer in the general population: from cancer registration to molecular diagnosis.

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) is one of the most common inherited disorders predisposing to cancer. The genes responsible for the disease have recently been cloned and characterised; their mutations induce a generalised genomic instability which is particularly evident at microsatellite loci (replication error (RER)+ phenotype). AIMS: To investigate how to select individuals and families in the general population who should be screened for constitutional mutations predisposing to colorectal cancer. PATIENTS/METHODS: Between 1984 and 1995, 1899 colorectal malignancies in 1831 patients were registered, and in 1721 of these (94%), family trees could be obtained. Patients and families were classified into five categories according to a more or less likely genetic basis: HNPCC; "suspected" HNPCC; juvenile cases; aspecific cancer aggregation; sporadic cases. In 18 families with HNPCC as well as in 18 with suspected HNPCC, microsatellite instability in tumour tissues and constitutional mutations of two DNA mismatch repair genes (MSH2 and MLH1) could be evaluated. RER status was studied with five markers (BAT40, D2S123, D18S57, D17S787, and BAT26) in paraffin embedded tissues. Germline mutations of MSH2 or MLH1 genes were assessed on DNA and RNA extracted from lymphomonocytic cells, using reverse transcription polymerase chain reaction, single strand conformation polymorphism analysis, and direct DNA sequencing. RESULTS: HNPCC represented 2.6% and suspected HNPCC 4.6% of all registered colorectal neoplasms. Eleven out of 18 HNPCC families (61%) showed microsatellite instability as opposed to four (of 18) suspected HNPCC (22%; p<0.02). Three germline mutations (two in MSH2 and one in MLH1 gene) were found in three different large HNPCC families, whereas no mutations were detected in suspected HNPCC. CONCLUSIONS: In this study of cancer genetic epidemiology, data from a tumour registry were analysed and this ultimately led to the identification and selection of families that should be tested for mutator gene mutations. With the use of a population based approach, the incidence of mutations was appreciably lower than previously reported and limited to families with full blown HNPCC. It is possible that in most families with a clinical spectrum of HNPCC (or suspected HNPCC) other DNA mismatch repair genes are involved in the pathogenesis of the disease.

Adaptor Proteins, Signal Transducing↗
PubMed1999

T cell receptor repertoire in B cell lymphoproliferative lesions in primary Sjögren's syndrome.

OBJECTIVE: Studies have analyzed T cell receptor (TCR)-Vbeta in benign, minor salivary or lacrimal gland, or kidney lesions in Sjögren's syndrome (SS). We investigated SS related lymphoproliferative lesions. METHODS: By "family" reverse transcriptase polymerase chain reaction, we studied the expression of 20 different TCR-Vbeta families in parotid lymphoproliferative lesions and peripheral blood lymphocytes (PBL) from 7 patients with primary SS, in PBL from 6 primary SS patients with no associated lymphoproliferative disorder, and in activated PBL from 2 healthy controls. T cell clonal expansion was investigated in 10 Vbeta families (i.e., the most expanded ones and those previously implicated in SS pathogenesis) by single strand conformation polymorphism (SSCP) analysis. Frozen sections from parotid gland specimens were tested by immunohistochemistry for the expansion of selected Vbeta families. Viral infection within the parotid lesions and serum autoantibody response were also studied. RESULTS: An unrestricted Vbeta pattern was observed. The most widely expressed Vbeta family in parotid lesions was Vbeta2, and Vbeta immunohistochemistry results were concordant with Vbeta mRNA findings. A similar pattern was observed in PBL, although the Vbeta2 family was expressed at lower levels. The parotid/PBL ratio was occasionally > 1.8-2.0 (indicative of local Vbeta overexpression) in different Vbeta families. T cell expansion proved to be largely polyclonal by SSCP analysis, and scattered T cell clonotypes were detected within different Vbeta families, with a different pattern from patient to patient. CONCLUSION: Our observations in SS related lymphoproliferative lesions largely reflect previous evidence in fully benign lesions. The pathogenetic events involved in autoimmune benign lesions in SS may then persist and play a role in SS related lymphoproliferative disorders. The link between the observed TCR-Vbeta repertoire and specific local triggering (auto)antigens remains to be elucidated.

Adult↗