Assessment of the role of Fanconi Anemia (FA) genes in colorectal cancer: A new pathogenetic pathway?

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Background: Fanconi Anemia (FA) is an autosomal recessive disease marked by congenital defects, bone marrow failure, and high incidence of leukemia and solid tumors. Eight FA associated genes have been cloned, and their products are thought to function in an integrated pathway which includes BRCA genes and maintains genomic stability. A molecular mechanism involved in the development and progression of some human malignancies, including colorectal cancer, is represented by a defective replication fidelity. Here we tested the role of the main FA genes in colorectal cancer (CRC). Methods: One hundred consecutively-collected patients with histologically-proven diagnosis of CRC and no mutation in the main mismatch repair genes (MLH1 and MSH2) were included into the study. Genomics DNA was screened using DHPLC for FANC-C/G/E/F genes and using MPLA for FANC-A/D2 genes. All PCR products with abnormal DHPLC profiles were sequenced on an automated sequencer. For 28 cases, tumor tissue samples were also analyzed. To date, total RNA was isolated from paired normal and tumor samples of 12 CRC patients. Gene expression was quantified by real-time RT-PCR using the Taqman approach. Results: At germline level, 2 cases presented FANC-C sequence variations (Asp267Ser, Val449Ser) and 5 cases showed a exon 26 deletion in FANC-A as detected by MLPA analysis. Among the 28 tumor samples available from patients negative for mutations in germline DNA, 2 (7%) cases presented a FANC-E mutation (Ala552Thr). Moreover, one of such somatic samples presented a BRCA2–8765delAG mutation (BRCA2 is also recognized as FANC-D1 gene). Assuming as significant difference in gene expression the presence of a variation of more than 50% in mRNA levels between normal and corresponding tumor samples, all tested FA genes (FANC-C/G/E/F) were found overexpressed in 5/12 (42%) tumor samples. Conclusions: Although preliminary, our findings seem to identify a subset of CRC patients with alterations in the FA/BRCA pathway which is required for the activation of DNA repair. Ongoing molecular analyses will better clarify the real frequency of each alteration in FA genes and their relationship with the histological and/or clinical features in colorectal cancer.

No significant financial relationships to disclose.

Serial RT-PCR detection of circulating tumour cells as a marker of disease progression in patients with malignant melanoma

18009

Background: Detection of circulating malignant cells (CMCs) through a reverse transcriptase-polymerase chain reaction (RT-PCR) assay seems to be a demonstration of systemic disease. We here evaluated the prognostic role of RT-PCR assays in serially-taken peripheral blood samples from patients with malignant melanoma (MM). Methods: One hundred forty-nine melanoma patients with disease stage ranging from I to III were consecutively collected in 1997. A multi-marker RT-PCR assay was used on peripheral blood samples obtained at time of diagnosis and every 6 months during the first two years of follow-up (total: 5 samples). Univariate and multivariate analyses were performed after 83 months of median follow-up. Results: Detection of at least one circulating mRNA marker was considered a signal of the presence of CMC (referred to as PCR-positive assay). A significant correlation was found between the rate of recurrences and the increasing number of PCR-positive assays (P = 0.007). Presence of CMC in a high number (≥2) of analysed blood samples was significantly correlated with a poor clinical outcome (disease-free survival: P = 0.019; overall survival: P = 0.034). Multivariate analysis revealed that presence of a PCR-positive status does play a role as independent prognostic factors for overall survival in melanoma patients, adding precision to the predictive power of the disease stage. Conclusions: Our findings indicated that serial RT-PCR assay may identify a high risk subset of melanoma patients with occult cancer cells constantly detected in blood circulation. Prolonged presence of CMCs seems to act as a surrogate marker of disease progression or a sign of more aggressive disease.

No significant financial relationships to disclose.

Anabolic Steroid Nandrolone Augments Hepatic Regenerative Response in Rats

The success of recovery after liver resection depends on the regeneration and functions of the remnant liver. In this study we investigated whether liver regeneration was facilitated by nandrolone decaonate after two-thirds partial hepatectomy in rats. Study animals were pretreated with nandrolone (5 mg/kg), while control animals received a placebo. Animal were sacrificed at 12, 24, 48, and 72 hours. We compared the survival rates, liver function tests as well as the amount of apoptosis by terminal deoxynucleotidyl transferase-mediated deoxyuridine-biotin nick end labeling assay, and regeneration, which was expressed as ratio of proliferating cell nuclear antigen and restoration ratio. A significant increase in hepatocyte regeneration at 24 and 48 hours in partially hepatectomized rats treated with nandrolone decaonate was observed compared to controls. This observation was confirmed by the significant acceleration of the liver restoration rate, which was 1/5 faster than in partially hepatectomized controls. The results of this study indicate that liver regeneration in rats treated with nandrolone show a prompt, faster regeneration after partial hepatectomy.

Mediastinal images resembling thymus following 131-I treatment for thyroid cancer

The follow-up of Differentiated Thyroid Cancer conventionally includes serum thyroglobulin and periodic Whole Body Scans. The uptake of 131-I in normal and pathological tissues different from metastatic thyroid cancer sites is a cause of false-positive scans. Among them, mediastinal uptake caused by thymic hyperplasia can be observed. The aim of the present study was to review a series of 573 patients with differentiated thyroid cancer treated with 131-I after surgery between 1992 and 2003 looking above all for those with mediastinal images resembling thymus. This evaluation is presented together with some hypotheses on the relationships between thymus and thyroid. Moreover, some considerations are made on the differential diagnosis between thymus and mediastinal tumour thyroid residues.

Histochemical analysis of glycoconjugates in the domestic cat testis

The localization and characterization of oligosaccharide sequences in the cat testis was investigated using 12 lectins in combination with the beta-elimination reaction, N-Glycosidase F and sialidase digestion. Leydig cells expressed O-linked glycans with terminal alphaGalNAc (HPA reactivity) and N-glycans with terminal/internal alphaMan (Con A affinity). The basement membrane showed terminal Neu5Acalpha2,6Gal/GalNAc, Galbeta1,3GalNAc, alpha/betaGalNAc, and GlcNAc (SNA, PNA, HPA, SBA, GSA II reactivity) in O-linked oligosaccharides, terminal Galbeta1,4GlcNAc (RCA120 staining) and alphaMan in N-linked oligosaccharides; in addition, terminal Neu5acalpha2,3Galbeta1,4GlcNac, Forssman pentasaccharide, alphaGal, alphaL-Fuc and internal GlcNAc (MAL II, DBA, GSA I-B4, UEA I, KOH-sialidase-WGA affinity) formed both O- and N-linked oligosaccharides. The Sertoli cells cytoplasm contained terminal Neu5Ac-Galbeta1,4GlcNAc, Neu5Ac-betaGalNAc as well as internal GlcNAc in O-linked glycans, alphaMan in N-linked glycoproteins and terminal Neu5Acalpha2,6Gal/ GalNAc in both O- and N-linked oligosaccharides. Spermatogonia exhibited cytoplasmic N-linked glycoproteins with alphaMan residues. The spermatocytes cytoplasm expressed terminal Neu5Acalpha2,3Galbeta1,4 GlcNAc and Galbeta1,3GalNAc in O-linked oligosaccharides, terminal Galbeta1,4GlcNAc and alpha/betaGalNAc in N-linked glycoconjugates. The Golgi region showed terminal Neu5Acalpha2,3Galbeta1,4GlcNac, Galbeta1,4GlcNAc, Forssman pentasaccharide, and alphaGalNAc in O-linked oligosaccharides, alphaMan and terminal betaGal in N-linked oligosaccharides. The acrosomes of Golgi-phase spermatids expressed terminal Galbeta1,3GalNAc, Galbeta1,4GlcNAc, Forssmann pentasaccharide, alpha/betaGalNAc, alphaGal and internal GlcNAc in O-linked oligosaccharides, terminal alpha/betaGalNAc, alphaGal and terminal/internal alphaMan in N-linked glycoproteins. The acrosomes of cap-phase spermatids lacked internal Forssman pentasaccharide and alphaGal, while having increased alpha/betaGalNAc. The acrosomes of elongated spermatids did not show terminal Galbeta1,3GalNAc, displayed terminal Galbeta1,4GlcNAc and alpha/betaGalNAc in N-glycans and Neu5Ac-Galbeta1,3GalNAc in O-linked oligosaccharides.

Differential lectin binding patterns in the oviductal ampulla of the horse during oestrus

We investigated the oligosaccharide sequence of glycoconjugates, mainly sialoglycoconjugates, in the horse oviductal ampulla during oestrus by means of lectin and pre-lectin methods such as the KOH-neuraminidase procedure to remove sialic acid residues and incubation with N-glycosidase F to cleave N-linked glycans. Ciliated cells displayed N-linked oligosaccharides throughout the cytoplasm. The cilia glycocalyx expressed both N- and O-linked (mucin-type) oligosaccharides, both showing a high variety of terminal sequences. In the most non-ciliated cells, the whole cytoplasm contained N-linked oligosaccharides with terminal alphaGal as well as mucin-type glycans with terminal Forssman pentasaccharides. In a few scattered non-ciliated cells, the whole cytoplasm displayed sialylated N-linked oligosaccharides with terminal Neu5Ac-GalNAc and O-linked glycans terminating with neutral and/or alphaGalNAc, Neu5Ac alpha2,6Gal/GalNAc, Neu5AcGal beta1,3GalNAc. Supra-nuclear granules, probably Golgi zones, of non-ciliated cells showed mainly O-linked glycans rich in sialic acid residues. The luminal surface of non-ciliated cells showed N-linked oligosaccharides, containing terminal/internal alphaMan/alphaGlc, betaGlcNAc and terminal alphaGal, as well as mucin-type oligosaccharides terminating with a large variety of either neutral saccharides or sialylated sequences. Apical protrusions containing O-linked oligosaccharides with terminal Forssman pentasaccharide, Neu5Ac-Gal beta1,4GlcNAc, Neu5Ac-GalNAc were seen in non-ciliated cells scattered along the epithelium. These findings show the presence of sialoglycoconjugates in the oviductal ampulla epithelium of the mare and the existence of different lectin binding profiles between ciliated and non-ciliated (secretory) cells, as well as the presence of non-ciliated cell sub-types which might determine functional differences along the ampullary epithelium of mare oviduct.

Epidemiology of malignant breast tumors in the province of Sassari (Sardinia, Italy) in the period 1992-2002

The aim of this study was to evaluate the incidence of malignant breast tumors in the Province of Sassari, Sardinia (Italy) in the period 1992-2002 and to report the variations in comparison to the 1974-1985 period. The analysis of our data showed that the overall number of malignant breast tumors was more than doubled from 1,139 cases in the period 1974-1985 to the 2,735 cases in the period 1992-2002, and the mean rate/100,000 changed from 43.4 to 106.0. The incidence in the age classes 45-64 years, which were at enhanced risk for breast cancer, was globally increased, changing from 143.6/100,000 to 198.7/100,000. On the other hand, the incidence in the youngest age classes (30-34 yrs) was reduced from 59.5% to 27.0%. The analysis of the histotypes showed a relative reduction of ductal carcinoma in the period 1992-2002 in comparison to the previous period 1974-1985 (65.2% vs 82.0%) whereas the incidence of anaplastic forms increased in advanced ages of life. We reported an important reduction of T0 tumors from 3.4% to 0.1%. These data could be due to the low diffusion of screening programs in Sardinia. Tumor metastases were more frequent in advanced age classes. In conclusion, the worrying data of the strong reduction of T0 cases, the increased age of first diagnosis and the advanced forms with positive nodal metastases showed that the prevention program has not been yet well organized.

Epidemiological aspects of ovarian malignancies in North Sardinia in the period 1992-2001

Malignant ovarian tumors have been continuously increasing in Western countries and represent the leading cause of death for gynecological cancer. In fact, the mortality for malignant ovarian tumors remains very high with a low percentage of 5-year survival in the advanced stage of disease. The aim of this study was to evaluate the incidence trend and epidemiological characteristics of malignant ovarian tumors in the Province of Sassari, Sardinia (Italy) in the period 1992-2001 and to report the variations in comparison to the 1974-1985 period. The analysis of our data regarding the period 1992-2001, if compared with those of the period 1974-85, showed an increase of malignant ovarian tumors which triplicated achieving an incidence of 11.99/100,000 vs 4.27/100,000. The analysis of our epidemiologic data showed an increase of the age of first diagnosis (mean 60.9 years for epithelial ovarian tumors), the occurrence of the cancer in women at low socio-economic levels and a family history of cancer among the patients with malignant ovarian tumors. These data suggest that both local environmental factors combined with genetic characteristics play a role in the pathogenesis of ovarian tumors. The genetic characteristics could be of particular interest because Sardinia has been through the centuries a geographical area with little population migration. The marked increase in the incidence of ovarian tumors in the last several years points out the need to organize systematic screening by ultrasonography in our population.

Ischemic preconditioning protects intestine from prolonged ischemia

Ischemic preconditioning (IP), obtained by exposure to brief periods of vascular occlusion, improves organ tolerance to prolonged ischemia. The aim of this study was to evaluate the effects of IP on intestinal morphology. Forty rats were subjected to sham surgery (n = 20, group I) or intestinal preconditioning (n = 20, group II) with a cycle of brief ischemia/reperfusion (10-minute occlusion of superior mesenteric artery [SMA], followed by 10-minute reperfusion) before prolonged ischemia produced by SMA occlusion (45 minutes). Five animals in each group were sacrificed 2, 12, 24, and 48 hours after reperfusion. Intestinal samples were processed for light and electron microscopy. A TUNEL assay was performed to detect apoptosis. Statistical analysis used Student t test and Kaplan-Meier survival curves. The overall mortality for the sham-operated group was 15%, while no animals of group II died (NS). Histological evaluation showed early detachment of epithelial cells from villous stroma accompanied by marked congestion and edema. Successive morphological changes were represented by leukocyte infiltration, focal necrosis, and marked villus denudation or loss. Group II animals showed significantly reduced inflammatory infiltrates in the lamina propria and a greater villus height compared to group I. The maximum number of apoptotic nuclei was observed in both groups, Following 2 hours of reperfusion group II animals showed significantly, greater apoptosis at 2 and 12 hours after reperfusion (P <.05). Electron microscopy showed severe mitochondrial and basement membrane damage. The findings from this study confirm that IP preconditioning attenuates morphological alterations that are invariably present after prolonged ischemia and reperfusion.

Microsatellite instability and mutation analysis among southern Italian patients with colorectal carcinoma: detection of different alterations accounting for MLH1 and MSH2 inactivation in familial cases

BACKGROUND

Microsatellite instability (MSI) is due to defective DNA mismatch repair (MMR) and has been detected at various rates in colorectal carcinoma (CRC). The role of MSI in colorectal tumorigenesis was assessed further in this study by both microsatellite analysis of two CRC subsets [unselected patients (n = 215) and patients <50 years of age (n = 95)], and mutation screening of the two major MMR genes MLH1 and MSH2 among familial CRC cases.

PATIENTS AND METHODS

PCR-based microsatellite analysis was performed on paraffin-embedded tissues. In CRC families, MLH1/MSH2 mutation analysis and MLH1/MSH2 immunostaining were performed on germline DNA and MSI+ tumour tissues, respectively.

RESULTS

The MSI+ phenotype was detected in 75 (24%) patients, with higher incidence in early-onset or proximally located tumours. Among 220 patients investigated for family cancer history, MSI frequency was markedly higher in familial [18/27 (67%)] than in sporadic [32/193 (17%)] cases. Three MLH1 and six MSH2 germline mutations were identified in 14 out of 36 (39%) CRC families. Prevalence of MLH1/MSH2 mutations in CRC families was significantly increased by the presence of: (i) fulfilled Amsterdam criteria; (ii) four or more CRCs; or (iii) one or more endometrial cancer. While MSH2 was found mostly mutated, almost all [8/9 (89%)] familial MSI+ cases with loss of the MLH1 protein were negative for MLH1 germline mutations.

CONCLUSIONS

Both genetic (for MSH2) and gene-silencing (for MLH1) alterations seem to be involved in CRC pathogenesis.

The incidence of female genital tumors in the Province of Sassari in the period 1992-2000

The incidence of gynecologic tumors in the Province of Sassari in the period 1992-2000 has been studied in order to estimate their value and to make a comparison with the data of the period 1974-83. The analysis of our data regarding the period 1992-2000, if compared with those of the previous period 1974-83, showed a change in the percentage distribution of all gynecologic tumors, with an increase in the incidence of malignant tumors of the ovary (from 17.1% to 28.0%) and a reduction in the incidence of endometrial carcinoma (from 52.1% to 45.0%). Cervix cancer seemed stationary with a mild reduction (from 26.8% to 23.0%). The data showed, with regard to the incidence per 100,000, an increase of endometrial carcinoma (19.05 per 100,000 vs 11.99 per 100,000) and malignant ovarian tumor (11.99 per 100,000 vs 3.95 per 100,000). Our data reported a worrying increase of hormonal-dependent tumors in North Sardinia such as endometrial and ovarian cancer with the highest increase in malignant ovarian tumors. In comparison to the previous period we confirmed a historically low incidence of cervical and external genitalia tumors (vulva and vagina) in North Sardinia.

B-cell lymphopenia and hypogammaglobulinemia in thymoma patients

Thymic tumors represent a unique neoplastic disease associated with various immune-mediated syndromes. Immune impairment is generically recognized to be associated with thymoma. Hypogammaglobulinemia and recurrent pulmonary infections in thymoma patients define Good's syndrome. Apart from sporadic reports focusing on this topic, there is still a lack of knowledge on immune assessment and clinical sequelae in thymoma patients. The present study was performed to evaluate immunoglobulin levels, CD19(+) B lymphocytes, and CD3(+) T lymphocytes in a large series of thymoma patients from a single institution. The occurrence of recurrent severe infections was related to immunological findings to identify the possible correlation with the immunodeficiency status. Eighteen patients (eight males, ten females, mean age: 56 years, range: 19-75) with a pathological diagnosis of thymic tumor were studied. Six patients suffered from clinical recurrent pulmonary infections. Blood samples were collected to measure serum immunoglobulins and analyze immunophenotype. Low T lymphocyte number was found in 22% of the patients. T lymphocytosis was present in one patient. Panhypogammaglobulinemia was found in 4 of 18 patients (22%). Conversely B lymphopenia was a frequent finding in this series of thymoma patients (9 of 18, 50%). Five of six patients (83%) with recurrent infections had B lymphopenia, while only two (33%) had panhypogammaglobulinemia. B lymphopenia often occurred in this series of thymoma patients and was related to susceptibility to recurrent infections more than hypogammaglobulinemia. Therefore, immunophenotype has to be monitored in follow-up of thymoma patients because it may reveal significant abnormalities.

BRCA1 and BRCA2 germline mutations in Sardinian breast cancer families and their implications for genetic counseling

BACKGROUND

The Sardinian population is genetically homogeneous and could be useful in understanding better the genetics of a complex disease like breast cancer (BC).

PATIENTS AND METHODS

Using a screening assay based on a combination of single-strand conformation polymorphism, denaturing high-performance liquid chromatography and sequence analysis, 47 Sardinian families with three or more BC cases were screened for germline mutations in BRCA1 and BRCA2 genes.

RESULTS

Three BRCA1/2 germline sequence variants were identified. While BRCA2-Ile3412Val is a missense variant with unknown functional significance, BRCA2-8765delAG and BRCA1-Lys505ter are two deleterious mutations (due to their predicted effects on protein truncation), which were found in seven families (15%). BRCA2-8765delAG was found in six of eight (75%) BRCA1/2-positive families and seven of 501 (1.4%) unselected and consecutively collected BC patients. Prevalence of BRCA1/2 mutations in BC families was significantly correlated with the total number of female BCs (P <0.01) and increased by the presence of (i) at least one case of ovarian or male BC, or (ii) three generations affected, or (iii) bilateral BC.

CONCLUSIONS

Identification of such features should address BC patients and their families to genetic counseling and BRCA1/2 mutational analysis. In addition, this is the first report of a detailed BRCA1/2 mutation screening in Sardinia, having immediate implications for the clinical management of BC families.

Consultation-liaison psychiatry in obstetrics and gynecology

Data documenting the activity of Modena and Reggio Emilia University Hospital Consultation-Liaison Psychiatry Psychosomatic Service (C-LPPS) to the 59 bed gynecological-obstetric unit are compared to the corresponding European Consultation Liaison Workgroup (ECLW) study results and discussed in the light of recent epidemiological studies suggesting a low rate of detection and psychiatric referral in obstetric and gynecological patients. All psychiatric consultations of gynecological-obstetric inpatients during a 3-year (1996-1998) period were included in this study and data were derived from valid and reliable consultation forms tested for reliability. Within the 3-year period 55 patients were referred to C-LPPS by the gynecological-obstetric unit for psychiatric consultation. Referral rate was 0.5% of the admitted patients in the unit. The gynecological-obstetric group represented 2.5% (vs. 4.5% ECLW study) of all psychiatric consultations requested in the study period. The most frequent reasons for referral were: current psychiatric symptoms (47.3% Modena study vs. 39% ECLW), psychiatric history (20% vs. 7.3%), unexplained physical symptoms (12.7% vs. 16.2%) and coping-compliance problems (3.6% vs. 16.6%). The most common ICD-10 psychiatric diagnoses were: neurotic, anxiety and adjustment disorders (41.8% vs. 31.2%), mood disorders (29% vs. 18.4%), personality disorders (7.3% vs. 6.1%), schizophrenic and other psychotic disorders (5.5% vs. 7%).

Chromosomal abnormalities and microsatellite instability in sporadic endometrial cancer

Defective DNA mismatch repair and nonfunctional mechanisms controlling the proper progression of the cell cycle have been proposed as being responsible for the genomic instability and accumulation of karyotypic alterations in endometrial cancer (EC). To assess whether numerical chromosomal anomalies (aneuploidy) and microsatellite instability (MSI) might be representative of distinctive tumour behaviour, paraffin-embedded tissue samples from 86 patients with sporadic EC were evaluated by both fluorescence in situ hybridisation (FISH) and microsatellite analysis, using free nuclei and genomic DNAs (respectively). Approximately one-third of the tumours analysed (24/74; 32%) exhibited MSI, whereas 38/86 (44%) of the EC samples displayed aneuploidy. The majority of the unstable cases (15/24; 63%) were from advanced-stage patients. Conversely, 23 (61%) out of the 38 tumours with aneuploidy were from early-stage patients. No apparent correlation was found between MSI and aneuploidy, whereas the immunohistochemical (IHC) analysis revealed that inactivation of the MLH1 mismatch repair gene may be involved in the majority of the MSI+ sporadic ECs. No genetic or cytogenetic alteration analysed here seems to add any significant predictive value to the stage of disease.

Prevalence and prognostic role of microsatellite instability in patients with rectal carcinoma

BACKGROUND

Association between microsatellite instability (MSI) and favorable postoperative survival in patients with colorectal cancer receiving adjuvant chemotherapy has been indicated. To evaluate whether an analogous positive prognostic role of MSI could be present in rectal carcinoma (RC; most RC patients receive adjuvant radiotherapy), PCR-based microsatellite analysis of archival RCs and statistical correlation with clinico-pathological parameters were performed.

PATIENTS AND METHODS

DNA from paraffin-embedded paired samples of tumors and corresponding normal tissue from 91 RC patients was analyzed for MSI using five microsatellite markers (tumors were classified as MSI(+) when two or more markers were unstable).

RESULTS

Seventeen (19%) RC patients exhibited a MSI(+) phenotype. Prevalence of instability was found in patients with earlier RC onset (28% in cases with diagnosis age < or =55 years versus 15% in cases >55 years), whereas similar MSI frequencies were observed in patients with different disease stage or receiving different adjuvant therapies. While MSI was detected in seven (64%) of 11 familial patients, a remarkably lower MSI incidence was observed in sporadic cases (10/80; 12.5%). A significant association with better disease-free survival (DFS) and overall survival (OS) was found for MSI(+) patients (median DFS/OS, 30/32 months) in comparison to MSI(-) ones (median DFS/OS, 18/21 months) (P <0.001).

CONCLUSIONS

MSI was demonstrated to be a strong molecular prognostic marker in rectal carcinoma, independent of the administered treatment (radiotherapy, chemotherapy or both).

Cytoskeletal proteins and resident flora

Recent observations demonstrate that enteropathogenetic and enterohaemorrhagic bacteria, as well as other non enteropathogenetic bacteria (Listeria, Coxiella Burnetii), may subvert the host cell cytoskeleton. Models from enteropathogenic bacteria demonstrate that cytoskeletal proteins are required for bacteria binding to the enterocytes and that they play a role in the immune response of the host to intestinal bacteria. The cytoskeletal protein family Tropomyosins is present in all eukaryotic cells, with multiple isoforms regulated by multiple genes. Of the different Tropomyosin isoforms, TM5 has been shown to be expressed in colonic and jejunal epithelial cells, while TM1 in colonic and jejunal smooth muscle. In vitro studies have shown the presence of serum and mucosal IgG against TM5 in almost two thirds of patients with ulcerative colitis, suggesting: a. a possible autoimmune response to Tropomyosin in these patients; b. the hypothesis that the development of pouchitis may be related to the expression of TM5 in the ileal pouch; c. the use of probiotics in the treatment of pouchitis. Overall, the new expression of cytoskeletal proteins on the cell surface appears to be possibly induced by several mechanisms, including intestinal bacteria and apoptosis. The expression of cytoskeletal proteins on the cell surface may induce tolerance or autoimmune response on target cells. Further investigations are, however needed on the possible role of cytoskeletal proteins in human diseases.

Roles of two white-rot basidiomycete fungi in decolorisation and detoxification of olive mill waste water

A Phanerochaete chrysosporium strain was isolated from Moroccan olive mill waste water (OMW) and its ability to degrade OMW in different culture conditions was investigated and compared to that of Pleurotus ostreatus. The results indicated that Ph. chrysosporium isolate is more efficient than Pl. ostreatus in decolorising and detoxifying OMW in the presence of added nutrients. Ph. chrysosporium is able to remove more than 50% of the colour and phenols from OMW within 6 days of incubation, whereas Pl. ostreatus needs more than 12 days to reach similar results in the same conditions. Many factors affecting the treatment of diluted OMW (20%) by Ph. chrysosporium were studied, including the effects of added nutrients, initial pH, temperature and inoculated biomass. Once the optimisation of 20% OMW biodegradation process had been set up, higher OMW concentrations (50%) were tested. The results show that the fungus is capable of reducing all parameters analysed (colour A395, phenol content and chemical oxygen demand) by at least 60%, after only 9 days of growth.

[Thymoma and somatostatin analogs. Biology, diagnostic and clinical practice]

Thymic tumours are rare neoplasms which generally follow a slow pattern of growth, showing their aggressiveness locally through the infiltration of adjacent organs and they rarely metastasise hematogenically. In the presence of locally advanced, metastatic or inoperable disease, combined strategies including chemotherapy, radiotherapy and surgery are now being evaluated. Scintigraphy with 111In DTPA-D-Phe 1 octreotide was used for the first time in a relevant series of patients with thymic tumour (13 cases) by our research group. The presence of somatostatin receptors (ss-R) assayed in vivo provided the rationale for the use of a treatment based on the octreotide analog in a patient with thymoma and aplasia of the erythroid series (pure red cell aplasia, PRCA) in whom a complete response for the tumour and the remission of anemia was obtained. The efficacy of this treatment was confirmed by our series of patients with chemoresistant thymic tumour and by national and international confirmations. These data, ranging from in vivo diagnosis to treatment and the in vitro study of receptor expression, confirm that somatostatin plays a major role in thymic tumours.

Peripheral ganglia supplying the genital smooth musculature in the female pig: an experimental study

The aim of the present study was to locate the sensory and autonomic ganglia innervating the female genital musculature in pigs. The retrograde neuronal tracers horseradish peroxidase (HRP) or fast blue (FB) were injected into the left retractor clitoridis muscle (RCM), which was treated as a typical model of the genital smooth musculature. Labelled cells were found in ipsilateral dorsal root ganglia S1-S4, in bilateral sympathetic paravertebral ganglia from L5-L6 or L6-L7 to S3 and in the left and right caudal mesenteric ganglion. In two of the five animals treated, presumably preganglionic parasympathetic cells were labelled in the ipsilateral intermediate grey substance of the segments S1-S2.

Purification, characterization, and functional role of a novel extracellular protease from Pleurotus ostreatus

A new extracellular protease (PoSl; Pleurotus ostreatus subtilisin-like protease) from P. ostreatus culture broth has been purified and characterized. PoSl is a monomeric glycoprotein with a molecular mass of 75 kDa, a pI of 4.5, and an optimum pH in the alkaline range. The inhibitory profile indicates that PoSl is a serine protease. The N-terminal and three tryptic peptide sequences of PoSl have been determined. The homology of one internal peptide with conserved sequence around the Asp residue of the catalytic triad in the subtilase family suggests that PoSl is a subtilisin-like protease. This hypothesis is further supported by the finding that PoSl hydrolysis sites of the insulin B chain match those of subtilisin. PoSl activity is positively affected by calcium. A 10-fold decrease in the K(m) value in the presence of calcium ions can reflect an induced structural change in the substrate recognition site region. Furthermore, Ca(2+) binding slows PoSl autolysis, triggering the protein to form a more compact structure. These effects have already been observed for subtilisin and other serine proteases. Moreover, PoSl protease seems to play a key role in the regulation of P. ostreatus laccase activity by degrading and/or activating different isoenzymes.

Solvent-free asymmetric aminoalkylation of electron-rich aromatic compounds: stereoselective synthesis of aminoalkylnaphthols by crystallization-induced asymmetric transformation

Electron-rich aromatic compounds such as 2-naphthol give a faster and asymmetric 1-aminoalkylation with high yields when treated with (R)-1-phenylethylamine and aromatic aldehydes in solvent-free conditions. An asymmetric transformation of a second kind, probably induced by the preferential crystallization of one diastereomer, affords the straightforward and stereoselective synthesis of aminoalkylnaphthols. Mechanisms predictable for this asymmetric reaction are reported. The absolute configurations and the conformations of the unknown aminonaphthols are widely ascertained.

Protective role of tauroursodeoxycholate during harvesting and cold storage of human liver: a pilot study in transplant recipients

BACKGROUND

Ischemia-reperfusion injury is a major cause of early graft dysfunction after liver transplantation. Tauroursodeoxycholic acid (TUDCA), a natural amidated hydrophilic bile salt, protects from cholestasis and hepatocellular damage in a variety of experimental models, as well as from ischemia-reperfusion injury. We investigated in the human liver transplantation setting the effect of the addition of TUDCA at time of liver harvesting and cold storage on the intra- and postoperative enzyme release and liver histopathology at the end of cold storage, at reperfusion, and 7 days after transplantation.

METHODS

Eighteen patients undergoing elective liver transplantation were studied, including 6 serving as controls. In six patients, TUDCA was added to the University of Wisconsin solution used during harvesting and cold storage, to reach final concentrations of 2 mM. In three of these patients, TUDCA (3 g) was infused in the portal vein of the donor before organ explantation; in the other three cases, TUDCA was given through both routes.

RESULTS

The use of TUDCA did not cause adverse events. The release of aspartate aminotransferase in the inferior vena cava blood during liver flushing was significantly lower (P=0.05) in TUDCA-treated than in control grafts, as were cytolytic enzyme levels in peripheral blood during the first postoperative week (P<0.02). At electron microscopy, an overt endothelial damage (cytoplasmic vacuolization, cell leakage, and destruction with exposure of hepatocytes to the sinusoidal lumen) was invariably found in control grafts, both at reperfusion and at day 7 after transplant. These features were significantly ameliorated by TUDCA (P<0.001). Several ultrastructural cytoplasmic abnormalities of hepatocytes were seen. Among these, damage to mitochondria matrix and crystae was significantly reduced in TUDCA-treated versus control grafts (P<0.01). Mild to severe damage of bile canaliculi was a constant feature in control biopsies, with dilatation of canalicular lumen and loss of microvilli. Both these abnormalities were markedly ameliorated (P<0.001 by TUDCA). The best preservation was observed when TUDCA was given through both routes.

CONCLUSIONS

The use of TUDCA during harvesting and cold storage of human liver is associated with significant protection from ischemia-reperfusion injury. The clinical significance of this findings must be studied.

Structural and kinetic characterization of native laccases from Pleurotus ostreatus, Rigidoporus lignosus, and Trametes trogii

A comparative study has been performed on five native laccases purified from the three basidiomycete fungi Pleurotus ostreatus, Rigidoporus lignosus, and Trametes trogii to relate their different catalytic capacities to their structural properties. Spectroscopic absorption features and EPR spectra at various pH values of the five enzymes are very similar and typical of the blue oxidases. The analysis of the dependence of kinetic parameters on pH suggested that a histidine residue is involved in the binding of nonphenolic substrates, whereas both a histidine and an acidic residue may be involved in the binding of phenolic compounds. His and an Asp residue are indeed found at the bottom of a cavity which may be regarded as a suitable substrate channel for approaching to type 1 copper in the 3D homology models of the two laccases from Pleuorotus ostreatus (POXC and POXAlb) whose sequences are known.

Clinical significance of PCR-positive mRNA markers in peripheral blood and regional nodes of malignant melanoma patients. Melanoma Cooperative Group

Reverse-transcriptase polymerase chain reaction (RT-PCR) with multiple markers has been demonstrated to be highly sensitive in detecting metastatic cells in peripheral blood of malignant melanoma (MM) patients, and the circulating MM cells to be significantly correlated with disease stages. We further evaluated the presence of specific PCR-positive mRNA markers in peripheral blood as well as in regional nodes as an expression of tumor progression. Peripheral blood samples from 317 MM patients with either localized (n = 219) or metastatic (n = 98) disease were processed to obtain total cellular RNA. RT-PCR was performed using tyrosinase (TYR), p97, and MelanA/MART1 as mRNA markers. PCR products were analyzed by gel electrophoresis and Southern blot hybridization. In addition, paraffin-embedded samples of histologically proven tumor-negative lymph nodes from the subset of patients with localized disease were analyzed by RT-PCR, using radiolabeled primers for TYR and MelanA/MART1. The presence of mRNA markers was significantly correlated with tumor burden with a good correlation between risk of recurrence (evaluated in stage I-III patients) and increasing number of PCR-positive markers (p = 0.0002). Currently, for each patient, PCR results obtained at different times during follow-up are being analyzed, and any variation in the number of PCR-positive markers is being correlated to the clinical status. Molecular screening of histologically negative nodes for the presence of metastatic MM cells is also under evaluation. Preliminary assessment of a subset of MM patients with higher risk of recurrence will require longer follow-up in order to define the role of RT-PCR in monitoring these patients.

Detection of occult melanoma cells in paraffin-embedded histologically negative sentinel lymph nodes using a reverse transcriptase polymerase chain reaction assay

PURPOSE

Detection of occult metastasis before the development of clinical disease could allow more accurate staging, appropriate follow-up procedures, and adjuvant therapies in patients with malignant melanoma (MM). The sentinel lymph node (SLN) has been proposed as a reliable predictor of metastatic disease in the lymphatic basin draining the primary melanoma. In this study, we screened both paraffin-embedded SLNs and peripheral-blood (PB) samples from MM patients at various stage of disease using a multimarker reverse transcriptase polymerase chain reaction (RT-PCR) assay. The prognostic significance of the presence of PCR-positive markers was also evaluated.

PATIENTS AND METHODS

Total RNA was obtained from paraffin-embedded SLN sections and PB samples of 75 MM patients. RT-PCR was performed using tyrosinase and MelanA/MART1 as melanoma-associated markers. Radiolabeled PCR products were analyzed on denaturing polyacrylamide gels.

RESULTS

Good sensitivity of the RT-PCR assay on archival tissues was demonstrated after comparison of RT-PCR results on frozen and paraffin-embedded SLNs from 16 MM patients. Significant correlation between the disease stage and marker expression in both PB and SLN samples was observed; the highest value was for patients who were positive for both markers in SLN (P =.006). Progression of disease was significantly associated with the total number of PCR-positive markers in both PB (P =.034) and SLN (P =.001) samples.

CONCLUSION

Although sensitivity is lowered by the use of paraffin-embedded specimens, our data indicate that RT-PCR analysis of serial sections from archival SLNs may be helpful in improving detection of occult micrometastases, thus improving staging of patients with melanoma.

Cisplatin, dacarbazine, and fotemustine plus interferon alpha in patients with advanced malignant melanoma. A multicenter phase II study of the Italian Cooperative Oncology Group

BACKGROUND

In a previous study, the authors tested the combination of fotemustine (FM) 100 mg/m(2) intravenously (i.v.) on Day 1, dacarbazine (DTIC) 250 mg/m(2) i.v. on Days 2-5, and interferon alpha (IFNalpha) 3 MIU intramuscularly three times per week in 43 patients with advanced melanoma. An overall response rate of 40% and a median survival of 40 weeks were obtained. To evaluate whether the addition of cisplatin (CDDP) to this regimen could improve these results, the authors conducted a preliminary Phase I study and concluded that CDDP 25 mg/m(2) i.v. for 2 days can be combined safely with DTIC, FM, and IFNalpha. Herein, the authors report the results of a Phase II trial with this regimen.

METHODS

From June 1996 to February 1999, 64 patients with metastatic melanoma who were not amenable to surgery were enrolled in this study. Sixty eligible patients (32 males and 28 females; median age, 53 years) were treated with a combination of FM 100 mg/m(2) i.v. on Day 1, DTIC 300 mg/m(2) i.v. on Days 2-4, and CDDP 25 mg/m(2) i.v. on Days 3 and 4 recycled every 3 weeks. IFN alpha2b was administered at a dose of 3 MIU intramuscularly 3 times per week until disease progression.

RESULTS

A total of 189 courses were administered, with a median number of 3 courses per patient (range, 1-8 courses per patient). Eleven complete responses and 12 partial responses were observed, for an overall response rate of 38.3% (95% exact confidence interval, 26.1-51.8%). The median survival was 36 weeks. Neutropenia and thrombocytopenia affected 85% of patients and 68% patients and was World Health Organization Grade 3-4 in 40% and 50%, respectively. The side effects attributable to IFN alpha2b were mild and manageable. The other side effects were moderate and well controlled by supportive therapy.

CONCLUSIONS

The schedule used in this study demonstrated significant activity in patients with advanced, untreated melanoma. The addition of CDDP in the management of the patients in this series seemed to increase significantly both the proportion of patients who achieved a complete response and the probability of long term survival compared with a previous series of patients who were treated by the authors. However, considering the currently available therapies, this regimen does not seem to offer a special advantage in the treatment of patients with this disease. New agents and new protocols are needed.

Definition of the role of chromosome 9p21 in sporadic melanoma through genetic analysis of primary tumours and their metastases. The Melanoma Cooperative Group

Malignant melanoma (MM) is thought to arise by sequential accumulation of genetic alterations in normal melanocytes. Previous cytogenetic and molecular studies indicated the 9p21 as the chromosomal region involved in MM pathogenesis. In addition to the CDKN genes (p16/CDKN2A, p15/CDKN2B and p19(ARF), frequently inactivated in familial MM), widely reported data suggested the presence within this region of other melanoma susceptibility gene(s). To clearly assess the role of the 9p21 region in sporadic melanoma, we evaluated the presence of microsatellite instability (MSI) and loss of heterozygosity (LOH) in primary tumours as well as in synchronous or asynchronous metastases obtained from the same MM patients, using 9 polymorphic markers from a 17-cM region at 9p21. LOH and MSI were found in 27 (41%) and 11 (17%), respectively, out of 66 primary tumours analysed. In corresponding 58 metastases, MSI was found at higher rate (22; 38%), whereas a quite identical pattern of allelic deletions with 27 (47%) LOH+ cases were observed. Although the CDKN locus was mostly affected by LOH, an additional region of common allelic deletion corresponding to marker D9S171 was also identified. No significant statistical correlation between any 9p21 genetic alteration (LOH, MSI or both) and clinicopathological parameters was observed.

Microsatellite analysis at 10q25-q26 in Sardinian patients with sporadic endometrial carcinoma: identification of specification patterns of genetic alteration

BACKGROUND

Loss of heterozygosity (LOH) at chromosome 10q25-q26 has been reported previously in endometrial carcinoma (EC), suggesting the presence of tumor suppressor gene(s). Nevertheless, frequency of genome-wide microsatellite instability (MSI) has been demonstrated higher in EC than in other common malignancy, mostly due to defective DNA mismatch repair. The authors further evaluated the role of the chromosome 10q25-q26 in endometrial tumorigenesis as well as the clinical significance of any observed genetic alteration in sporadic EC.

METHODS

Paired normal and tumor samples from 94 Sardinian patients with sporadic EC at various stages of disease were screened by polymerase chain reaction (PCR)-based microsatellite analysis. Genomic DNA was isolated from paraffin embedded tissues and amplified by PCR using microsatellite markers spanning approximately 14 cM at 10q25-q26. Microsatellite instability was studied at four loci mapping to different chromosomal locations.

RESULTS

Thirty-two (34%) EC patients were found negative for genetic alterations within the 10q25-q26 region. Among the remaining 62 (66%) EC cases, the authors identified 1) a minimum consensus region of LOH of approximately 1 cM, between D10S610 and D10S542 markers; and 2) a subset of tumors with prevalence of instability at 10q25-q26 (10qMI+), as expression of the presence of a MSI+ phenotype.

CONCLUSIONS

The authors' data establish the existence of significant correlations between disease stages and 10qMI+ (with or without MSI+). However, longer follow-up and additional studies are required to define the clinical significance of these findings as prognostic factors. Moreover, the minimum region of LOH at 10q25-q26 will be further analyzed for identifying the putative tumor suppressor gene involved in EC pathogenesis.