Biomedical subjects

Carlo Capella

Publications and source records attributed to Carlo Capella.

At least 19 recordsLinked to original sources

PubMed2025

Digital Immunophenotyping of Lung Atypical Carcinoids and Large Cell Neuroendocrine Carcinomas Identifies Three Subtypes With Specific Tumor-Immune Microenvironment Features.

Atypical carcinoids (ACs) and large cell neuroendocrine carcinomas (LCNECs) are defined by the WHO as intermediate- and high-grade lung neuroendocrine neoplasms, respectively, based on morphological criteria; however, treatment strategies remain debated. Given the emerging role of the tumor microenvironment (TME) and tumor-infiltrating lymphocytes (TILs) in cancer prognosis and therapy response, this study aimed to characterize the immune landscape of ACs and LCNECs comprehensively. Immunohistochemistry for T-cell markers (CD3, CD8), immune checkpoints (PD-1, PD-L1), HLA molecules (HLA-DR, HLA-I), and fibroblasts (α-SMA) was performed on a re-evaluated cohort of 56 ACs and 104 LCNECs. Digital image analysis quantified intra-tumor (iTILs) and stromal (sTILs) CD3 and CD8 TILs in the whole slide and in specific tumor regions (invasive margin [IM] and central tumor [CT]). LCNECs exhibited significantly higher stromal T-cell infiltration, immune checkpoint expression, and HLA compared to ACs (p < 0.001), while α-SMA was more prominent in ACs. No ACs showed PD-L1 tumor expression. Digital quantification confirmed greater iTILs and sTILs in LCNECs across all regions, with moderate concordance to manual counts. Interestingly, TIL parameters were higher at the IM than in the CT (p < 0.001). Using Boruta feature selection algorithm, Principal Component Analysis and Hierarchical Clustering, three patient clusters were identified: Cluster 1 (mainly ACs, low TILs, favorable prognosis), Cluster 2 (mixed histology, intermediate TILs, moderate prognosis), and Cluster 3 (mostly LCNECs, high TILs, poor prognosis), with distinct TME marker profiles. PD-L1 tumor expression was strongly linked to Cluster 3. These findings suggest that ACs and LCNECs may be stratified into three distinct immune clusters, highlighting the heterogeneity of their tumor microenvironment and providing a rationale for further translational studies.

Humans↗

PubMed2006

The high frequency of de novo promoter methylation in synchronous primary endometrial and ovarian carcinomas.

PURPOSE: The methylation status of hMLH1, CDKN2A, and MGMT was investigated in a panel of synchronous cancers of the ovary and endometrium, fulfilling the clinicopathologic criteria for independent primary tumors to define the possible role of epigenetic mechanisms in the development of these cancers. EXPERIMENTAL DESIGN: Bisulfite-converted DNA from 31 tumors (13 endometrial and 18 ovarian carcinomas) and from matched normal tissue of 13 patients was analyzed by a methylation-specific PCR assay at the CpG-rich 5' regions of all three genes. In all tumors, we also investigated the presence of microsatellite instability and hMLH1 immunohistochemical expression in relation to hMLH1 hypermethylation status. RESULTS: Methylation of hMLH1, CDKN2A, and MGMT was detected in 39%, 41%, and 48% of endometrial and ovarian tumors, respectively. hMLH1 hypermethylation was observed in all tumors of five patients, and it was invariably associated with loss of hMLH1 protein and presence of microsatellite instability. CDKN2A and MGMT methylation was randomly detected among both endometrial (45% and 24% of cases, respectively) and ovarian carcinomas (39% and 39% of cases, respectively). Concordant methylation at two or three genes was observed in 35% of cases. CONCLUSIONS: Epigenetic inactivation of hMLH1, CDKN2A, and MGMT may be a common and early event in the development of synchronous primary endometrial and ovarian carcinomas and may qualify as a marker of a field cancerization encompassing the ovary and endometrium. Detection of MGMT hypermethylation may be useful to define a set of gynecologic malignancies with a specific sensitivity to alkylating chemotherapy.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Histidine decarboxylase, DOPA decarboxylase, and vesicular monoamine transporter 2 expression in neuroendocrine tumors: immunohistochemical study and gene expression analysis.

Histidine decarboxylase (HDC) and vesicular monoamine transporter 2 (v-MAT2) are involved in the biosynthesis and storage of histamine. DOPA decarboxylase (DDC) is involved in the biosynthesis of a variety of amines and shares a high degree of homology with HDC. HDC and v-MAT2 immunoreactivities (IR) have recently been detected in well-differentiated neuroendocrine tumors (WDNETs) and poorly differentiated neuroendocrine carcinomas (PDNECs) of various sites and have been proposed as general endocrine markers. We evaluated HDC and v-MAT2 IR in a series of 117 WDNETs and PDNECs from different sites. Western blotting analysis was performed to verify the specificity of anti-DDC and anti-HDC antibodies. Real-time RT-PCR was performed using specific probes for HDC and DDC on 42 cases, examined also for DDC IR. HDC and v-MAT2 IR were observed in the majority of WDNETs and PDNECs of all sites and HDC-IR cases were always also DDC-IR. In contrast, high levels of HDC mRNA were detected only in the gastroenteropancreatic WDNETs, which did not show increased DDC mRNA levels. On the other hand, bronchial carcinoids and lung PDNECs showed high DDC mRNA levels, but nearly undetectable HDC mRNA levels. Western blotting analysis showed a cross-reaction between anti-HDC and anti-DDC antibodies. HDC should not be considered as a general endocrine marker and HDC IR in bronchial carcinoids and PDNECs of the lung can probably be attributed to a cross-reaction with DDC.

Antibody Specificity↗

PubMed2006

Clinico-pathological features of a series of 11 oncocytic endocrine tumours of the pancreas.

Oncocytic changes may occur very infrequently in neuroendocrine tumours. To estimate the prevalence, pathological features and clinical behaviour of oncocytic endocrine tumours of the pancreas, we reviewed a series of 227 lesions from two institutions. Eleven cases with predominant oncocytic features were selected, representing 4.85% of the whole series. The morphological features and immunophenotype of such tumours did not differ from conventional endocrine pancreatic tumours, except for the presence of abundant eosinophilic and granular cytoplasm. Anti-mitochondrial antigen was positive in all cases tested, and by electron microscopy, numerous mitochondria were observed in the cytoplasm of tumour cells. The majority of cases were nonfunctioning, and in most cases, pathologic signs of malignancy, leading to a diagnosis of endocrine carcinoma, were observed. In addition, the three nonmalignant cases matched the criteria of well-differentiated tumours of uncertain malignant potential. Nearly 50% of the cases were clinically aggressive, and lymph node and liver metastases were present at the time of diagnosis in a minority of cases. Therefore, oncocytic endocrine pancreatic tumours represent a peculiar morphological and clinical variant characterised by frequent hormonal inactivity and malignant behaviour, which should be considered in the differential diagnosis, especially when dealing with a metastatic lesion.

Adenoma, Oxyphilic↗

PubMed2006

Chromosome band 6q deletion pattern in malignant lymphomas.

Deletion of chromosome arm 6q is a frequent karyotypic alteration found in a variety of cancers and lymphoproliferative disorders, including leukemia and lymphomas. We characterized 6q deletions in 35 malignant lymphomas, using conventional and molecular cytogenetic approaches, to define the deletion pattern of 6q in different histological types. Conventional cytogenetics revealed a 6q deletion in 46% of lymphomas, including two cases that showed 6q deletion as the sole chromosome anomaly. Interphase FISH analysis demonstrated allelic loss of 6q regions in 33 out of 35 cases (94.2%); the deletions were discontinuous, involving nonadjacent molecular regions. Although 6q deletion is a common event in all types of lymphomas, specific deletion patterns seem to characterize different histological types, suggesting that different tumor suppressor genes play different roles in different types of lymphomas. Two specific 6q regions deleted in diffuse large B cell lymphomas but not in follicular lymphomas may be implicated in the clinical transformation.

Chromosome Deletion↗

PubMed2006

Lipid-rich variant of pancreatic endocrine neoplasms.

Most pancreatic endocrine neoplasms (PENs) show characteristic and well-recognized endocrine morphology; however, a lipid-rich pattern, which can present a diagnostic problem in biopsies, has been reported, mostly as individual cases. Some have been included in descriptions of the rare clear-cell variant associated with von Hippel-Lindau (VHL) syndrome. The histogenesis, clinicopathologic characteristics, and significance of this lipid-rich pattern have not been unraveled. In this study, 11 PENs exhibiting foamy, microvesicular cytoplasm were analyzed. In some cases, the nuclei were distorted by the vesicles, and the usual endocrine chromatin pattern was not evident. The growth pattern was relatively diffuse, with vague compartmentalization of the cells by a delicate vasculature; prominent nesting was noted in only 4 cases. Pathology reports indicated substantial diagnostic challenge in these cases; on biopsies, 1 case was originally diagnosed as adrenal cortical carcinoma, another as renal cell carcinoma, a third as solid-pseudopapillary tumor, and a fourth had a fine needle aspiration cytologic diagnosis of adenocarcinoma. All cases were chromogranin and synaptophysin positive. Electron microscopy in 3 cases confirmed the cytoplasmic vesicles to be lipid vacuoles. Neurosecretory granules were also evident. Clinically, as in conventional PENs, there appeared to be two distinct subsets: Two cases were familial or functional/syndromic (1 with VHL and the other with MEN-1 and glucagonoma syndrome) and occurred in younger adults (ages 41 and 47 years); the majority (n = 9) were nonfunctional/nonsyndromic and nonfamilial. The latter group was mostly represented by elderly males (mean age: 65 vs. 58 years in conventional sporadic PENs). Immunohistochemically, markers implicated in VHL-associated neoplasia, including HIF-1alpha, inhibin, and Melan-A (in clear-cell PENs) and MUC6 (in serous cystadenomas) were mostly negative in lipid-rich PENs (1 of 10, 1 of 10, 0 of 10 and 0 of 10, respectively). In conclusion, the lipid-rich pattern, reminiscent of adrenal cortical cells, represents a distinct subset of PENs. It presents a diagnostic challenge for surgical pathologists, especially in biopsies. EM supports the name lipid-rich for this variant. The findings suggest that the pathogenesis of lipid-rich tumors may be different from the VHL-associated clear-cell variants of PENs.

Adenocarcinoma↗

PubMed2006

Genomic and expression profiling identifies the B-cell associated tyrosine kinase Syk as a possible therapeutic target in mantle cell lymphoma.

Among B-cell lymphomas mantle cell lymphoma (MCL) has the worst prognosis. By using a combination of genomic and expression profiling (Affymetrix GeneChip Mapping 10k Xba131 and U133 set), we analysed 26 MCL samples to identify genes relevant to MCL pathogenesis and that could represent new therapeutic targets. Recurrent genomic deletions and gains were detected. Genes were identified as overexpressed in regions of DNA gain on 3q, 6p, 8q, 9q, 16p and 18q, including the cancer genes BCL2 and MYC. Among the transcripts with high correlation between DNA and RNA, we identified SYK, a tyrosine kinase involved in B-cell receptor signalling. SYK was amplified at DNA level, as validated by fluorescence in situ hybridisation (FISH) analysis, and overexpressed at both RNA and protein levels in the JeKo-1 cell line. Low-level amplification, with protein overexpression of Syk was demonstrated by FISH in a small subset of clinical samples. After treatment with low doses of the Syk inhibitor piceatannol, cell proliferation arrest and apoptosis were induced in the cell line overexpressing Syk, while cells expressing low levels of Syk were much less sensitive. A combination of genomic and expression profiling suggested Syk inhibition as a new therapeutic strategy to be explored in lymphomas.

Apoptosis↗

PubMed2006

Cellular and molecular consequences of peroxisome proliferator-activated receptor-gamma activation in ovarian cancer cells.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a ligand-activated transcription factor. In addition to its canonical role in lipid and glucose metabolism, PPAR-gamma controls cell proliferation, death, and differentiation in several tissues. Here we have examined the expression of PPAR-gamma in ovarian tumors and the cellular and molecular consequences of its activation in ovarian cancer cells. PPAR-gamma was expressed in a large number of epithelial ovarian tumors and cell lines. The PPAR-gamma ligand ciglitazone inhibited the growth and clonogenic survival of ovarian cancer cells, inducing cell cycle arrest and cell death. Growth inhibition by ciglitazone was reversed by the PPAR-gamma antagonist GW9662, indicating the involvement of PPAR-gamma-dependent mechanisms. Microarray-based gene profiling revealed complex changes in the transcriptional program of ovarian cancer cells on treatment with ciglitazone and identified multiple pathways that may contribute to PPAR-gamma ligands' antitumor activity. Genes upregulated by ciglitazone were predominantly associated with metabolic, differentiation, and tumor-suppressor pathways, whereas downregulated genes were involved in cell proliferation, cell cycle, cell organization, and steroid biosynthesis. Collectively, our data indicate that PPAR-gamma activation by selective agonists is a valid strategy for ovarian cancer therapy and prevention, and should be tested alone and in combination with other anticancer drugs.

Cell Cycle↗

PubMed2005

Intratumour T cells, their activation status and survival in gastric carcinomas characterised for microsatellite instability and Epstein-Barr virus infection.

Gastric carcinomas (GCs) with high microsatellite instability (MSI) or an Epstein-Barr virus (EBV) infection are prevalently poorly differentiated adenocarcinomas with abundant lymphoid infiltration. The aims of the study were to clarify (1) if tumour-infiltrating lymphocytes (TILs) and cytotoxic-activated TILs are associated with a better clinical outcome in patients with GCs characterised for the presence of MSI and EBV; (2) if the nature and the activation status of TILs are involved in tumour cell apoptosis, evaluated using the M30 antibody, directed against a fragment of cytokeratin-18 caspase-cleaved during early steps of epithelial cell apoptosis. The immunophenotype of TILs and the tumour cell apoptosis were analysed with immunohistochemistry in 96 GCs, including 35 MSI GCs, and 61 GCs without MSI [microsatellite stable (MSS)], 17 of which were EBV+. MSI and MSS/EBV+ GCs displayed a significantly higher mean number of cytotoxic-activated TILs and apoptotic tumour cells than MSS/EBV- GCs (CD8+ TILs/HPF, 21.7 and 69.6 vs 6.4; T-cell intracellular antigen (TIA)-1+ TILs/HPF, 16.7 and 32.05 vs 5.2; granzyme B+ TILs/HPF, 7.5 and 8.6 vs 0.8; perforin+ TILs/HPF, 5.9 and 9.2 vs 0.9; and M30 IR tumour cells, 5.9 and 2.9 vs 2.3%). In addition to the most reliable clinico-pathological parameters (lymph node status, depth of tumour invasion and tumour stage), a univariate analysis showed that the presence of CD3+ TILs higher than 14.9 (p=0.01), CD8+ TILs higher than 9.5 (p<0.05) and MSI (p=0.02) were associated with better overall patient survival. Using a Cox regression model, only a high number of CD3+ TILs (p=0.02) and a low tumour stage (p=0.00001) were identified as independent prognostic factors. In conclusion, our study demonstrates that a high number of CD3+ and CD8+ TILs is a characteristic of MSI- and EBV-associated GCs and represents a favourable prognostic factor, independently of the pathogenesis of GCs.

Adenocarcinoma↗

PubMed2005

Immunohistochemical study of androgen receptors in breast carcinoma. Evidence of their frequent expression in lobular carcinoma.

Androgens and androgen receptors (AR) are involved in the pathogenesis of breast cancer. Epidemiological studies have shown a significant association between the risk of breast cancer and androgens. However, the functional role and clinical value of AR expression in breast carcinoma have still not been clearly defined. The present study was set up to investigate the prevalence of ARs in a series of consecutive invasive breast carcinomas (IBCs) and to evaluate the patterns of AR phenotypes in a series of selected invasive lobular carcinomas (ILCs). Among the 250 consecutive IBCs (consisting of 212 ductal and 38 lobular neoplasms), AR immunoreactivity was observed in 151/250 (60.4%) cases, being expressed in 118/212 (56%) ductal and 33/38 (87%) lobular carcinomas (a statistically significant difference, chi2=11.82). AR expression was frequently associated with ER (65.2%, chi2=14.33) and PR positivity (66.9%, chi2=7.36). Most AR positive cases showed a low proliferative index (63.7%) and a low or intermediate histological grade (G1-G2, 63.9%). Among the 80 selected ILCs, AR expression was observed in 64/80 (80%) cases. Our results confirm that ARs are expressed in most breast cancers. Moreover, we demonstrated that AR positivity is particularly marked in lobular neoplasms. In addition, AR positive carcinomas are frequently characterized by a low or intermediate grade, a low proliferative index and ER and/or PR co-expression.

Adenocarcinoma↗

PubMed2005

Allelotypes and fluorescence in situ hybridization profiles of poorly differentiated endocrine carcinomas of different sites.

PURPOSE: The aim of this work was to investigate the genotypic profiles of 36 poorly differentiated endocrine carcinoma (PDEC) of different sites to verify if their very similar phenotype may reflect similar pattern of genetic anomalies and if useful diagnostic or prognostic markers may be pointed out. EXPERIMENTAL DESIGN: All tumors were microallelotyped at 57 microsatellite on 11 autosomes and the allelotypes of a selected panel of tumors were validated by interphasic fluorescence in situ hybridization with centromeric probes for chromosomes 1, 3, 6, 11, 17, and 18 and a probe specific for p53. RESULTS: Regardless of the primary sites, PDECs exhibit very complex allelotypes (86%) and TP53 allelic imbalance (89%). Among these cases, fluorescence in situ hybridization analysis confirmed the presence of multiple aneusomies and a chromosome instability phenotype. Very low percentage of allelic imbalance (AI) and few aneuploidies were detected in only five PDECs for which an overall longer survival was observed. We found recurrent AI on 3p, 5, and 11q13 in lung PDECs, on 5q21, 8p, and 18q21 in colorectal PDECs and on 7 and 11q22 in gastric PDECs. Significantly better outcome was observed in patients with PDEC exhibiting 8q AIs and absence of AI at chromosome regions 6q25 and 6p. CONCLUSIONS: The concurrence of p53 inactivation and aneuploidies or chromosome instability are the main features of PDECs. However, the specific allelotypes observed in relation to primary site support the hypothesis that PDECs and exocrine carcinomas of all sites may share early pathogenetic mechanisms. Molecular markers of potential diagnostic and prognostic values for PDECs of different sites have been identified.

Adult↗

PubMed2005

Morphological and functional differences in haemostatic axis between kidney transplanted and end-stage renal disease patients.

End-stage renal disease (ESRD) is characterized by several atherothrombotic abnormalities, and kidney transplant seems to improve most of them. However, because it is not clear which mechanism is responsible for such improvement, our purpose was to clarify that point.We conducted a cross sectional study involving 30 ESRD patients, 30 ESRD kidney-transplanted patients (Ktx) and 30 healthy controls (C) to evaluate platelet morphology and function, atherothrombotic profile, endothelial abnormalities and cytokine levels involved in the insulin resistance/endothelial dysfunction. (i) Platelet morphology: The ESRD group showed platelet size similar to the other two groups (ESRD=3518x10(3)+/-549x10(3) nm2, C=3075x10(3)+/-197x10(3) nm2, Ktx=2862x10(3)+/-205x10(3) nm2) with similar platelet granules and number. (ii) Platelet surface glycoprotein: The CD41 and P-Selectin were similar between groups. (iii) Platelet intracellular calcium: Resting intracellular calcium was statistically higher in ESRD compared to the C group (ESRD=182.1+/-34.5, Ktx=126.7+/-14.1, C=72.0+/-11.0 nM, P<0.01). (iv) Hypercoagulability markers and natural anticoagulants: The Ktx and ESRD groups showed higher levels of hypercoagulability markers compared to the C group. A reduction in antithrombin activity was evident in ESRD compared to the Ktx group (P=0.03). (v) Endothelial morphology: The ESRD group showed a thickened vessel basal membrane compared to the Ktx and C groups with more endothelial sufference. (vi) Insulin resistance and pro-inflammatory cytokine profile: The ESRD showed a higher homeostasis model assessment provided equations for estimating insulin resistance (HOMA-IR) compared to the Ktx and C groups (ESRD=2.6+/-0.3, Ktx=1.8+/-0.2, C=1.1+/-0.1, P=0.005) and increased soluble tumor neurosis factor alpha (sTNFalpha) (P<0.05) and soluble vascular cell adhesion molecule (sVCAM) levels (P<0.01). Positive correlations were evident among HOMA-IR and sTNFalpha (P<0.001) and sVCAM (P=0.01), respectively. In a small subgroup of ESRD who underwent Ktx (five pts), our findings were confirmed at 1 year of follow-up, suggesting an improvement of almost haemostatic abnormalities. Kidney transplant is associated with a better atherothrombotic profile in ESRD, platelet intracellular calcium and cytokines seem to be most influenced by the transplant, while most morphological abnormalities are retained.

Adult↗

PubMed2005

Two PMS2 mutations in a Turcot syndrome family with small bowel cancers.

We report the clinicopathological, genetic, and immunohistochemical characterization of an atypical Turcot syndrome (TS) family with small bowel cancer. The tumor family history of a patient with cafè-au-lait spots (CALS) and early onset adenomas, duodenal cancer, and glioblastoma was positive for colonic adenoma (mother), jejunal (maternal grandfather), lung (father), and colorectal (paternal uncle) cancers. PMS2 genetic testing identified the nonsense 1951C>T (Q643X) and the missense 161C>T (S46I) mutations. PMS2 expression was absent in the proband's duodenal cancer with high microsatellite instability. The normal cells also displayed no PMS2 expression and some degree of instability. Our findings point out the association between PMS2 and TS, and support the hypothesis that patients with a few polyps, small bowel tumors with a very early onset, glioblastoma, and CALS should be considered as a variant of hereditary nonpolyposis colorectal cancer. A recessive model of inheritance caused by compound heterozygous mutations was consistent with the observed severe clinical phenotype and has important implications for predicting cancer risk in both the proband and his relatives.

Adenosine Triphosphatases↗

PubMed2005

Natural history of kidney graft survival, hypertrophy, and vascular function in end-stage renal disease type 1 diabetic kidney-transplanted patients: beneficial impact of pancreas and successful islet cotransplantation.

OBJECTIVE: Diabetes, hypertension, infections, and nephrotoxicity of certain immunosuppressive drugs (i.e., calcineurin inhibitors) can reduce functional survival of the kidney graft. Our aim was to evaluate survival, hypertrophy, and vascular function of the kidney graft in end-stage renal disease (ESRD) type 1 diabetic patients after transplant. RESEARCH DESIGN AND METHODS: The study population consisted of 234 ESRD type 1 diabetic patients who underwent kidney-pancreas (KP; 166 patients), successful kidney-islet (KI-s; 24 patients), and kidney (KD; 44 patients) transplant. Kidney size, graft survival, vascular function, and microalbuminuria were evaluated prospectively yearly for 6 years. Sixty-eight protocol kidney biopsies were performed routinely between 1993 and 1998 cross-sectionally (3.2 +/- 0.3 years from kidney transplant). RESULTS: The KP and KI-s groups had better cumulative kidney graft survival at 6 years than did the KD group (KP: 73%; KI-s: 86%; KD: 42%, P < 0.01). The KP group but not the KI-s/KD groups showed a persistent kidney graft hypertrophy up to 6 years of follow-up. A significant increase in creatinine levels from baseline to year 6 was evident in the KD group (1.58 +/- 0.08 to 2.78 +/- 0.44 mg/dl, P < 0.05) but not in the KP/KI-s groups. The KP/KI-s groups only showed a reduction of renal resistance index from baseline to year 6 (KP at baseline: 0.74 +/- 0.01 to 0.68 +/- 0.01%, P < 0.01; KI-s at baseline: 0.72 +/- 0.02 to 0.69 +/- 0.02%, P < 0.05). At year 6, an increase from baseline in urinary albumin excretion was observed only in the KD group (31.4 +/- 9.0 to 82.9 +/- 33.6 mg/l, P < 0.05). Preliminary data suggested that graft nitric oxide (NO) expression was higher in the KP/KI-s groups than in the KD group (data not shown). CONCLUSIONS: In ESRD type 1 diabetic patients, KP and KI-s compared with KD resulted in enhanced kidney graft survival, hypertrophy, and vascular function.

Adult↗

PubMed2005

Aneuploidy, centrosome alteration and securin overexpression as features of pituitary somatotroph and lactotroph adenomas.

OBJECTIVE: To verify the presence of numerical chromosomal aberrations (NCAs) in different types of pituitary adenomas (PAs) and to investigate 2 of the mechanisms that are possibly related to aneuploidies in PAs: securin overexpression and centrosome alterations. STUDY DESIGN: Twenty-one PAs of different types were analyzed with interphase fluorescence in situ hybridization (FISH) on paraffin sections with centromeric probes for chromosomes 2, 3, 8, 11 and 12. In all cases, the immunohistochemical expression of securin was evaluated and the number of cells with abnormal nuclear shape recorded. The ultrastructural study of centrosomes was performed in a subset of 12 tumors. RESULTS: At interphase FISH analysis, growth hormone (GH)-cell and prolactin (PRL)-cell PAs showed multiple chromosome gains and a low frequency of chromosome losses, suggesting a hyperdiploid chromosome assessment. In contrast, in the other types of PAs a lower frequency of NCAs was observed. In addition, when compared to other types of PAs, GH-cell and PRL-cell adenomas showed overexpression of securin and a higher number of both cells with abnormal nuclear shape and cells with centrosomes. CONCLUSION: Somatotroph and lactotroph adenomas are characterized by aneuploidy, abnormal nuclear shape and centrosome amplification, which are possibly related to securin overexpression.

Adult↗

PubMed2004

CDX2 as a marker of intestinal EC-cells and related well-differentiated endocrine tumors.

Gastroenteropancreatic (GEP) endocrine tumors (ETs) are neoplasms showing different hormonal profiles and different clinical and prognostic features, which depend consistently on the site of origin. Histological features and general endocrine markers do not differentiate tumors in relation to their location, making it difficult to establish the site of origin of a GEP ET that has metastasized to the liver or lymph nodes. A site-specific marker would be particularly useful in the examination of small specimens where there is not sufficient material for an extensive study of the hormonal expression. CDX2 is a transcription factor that has been recently proposed as a marker of intestinal adenocarcinomas. Our aim was to evaluate the immunohistochemical expression of CDX2 in normal tissues and in 184 formalin-fixed and paraffin-embedded ETs to verify whether it could be used to identify intestinal ETs with a high degree of sensitivity and specificity. Of these cases, 154 were primary tumors (99 GEP and 55 non-GEP tumors), 101 were well-differentiated endocrine tumors, and 53 were poorly differentiated endocrine carcinomas (PDECs). Of the cases, 30 were metastases from differently located ETs. Nuclear CDX2 immunoreactivity was found in all EC-cells (serotonin-producing cells), in about 10% of G-cells (gastrin-producing cells), in about 30% of GIP-cells (gastric inhibitory peptide cells) and in a few motilin-positive cells of the normal intestinal mucosa, while other gastrointestinal endocrine cell types were CDX2 negative. All midgut EC-cell tumors, their metastases, and two of three pancreatic EC-cell ETs were diffusely and intensely CDX2 positive. The other GEP ETs, their metastases, as well as the non-GEP ETs, were all CDX2 negative, with the exception of four PDECs, five gastrinomas and one pheochromocytoma, which were only focally positive. We conclude that CDX2 may be considered a sensitive and specific marker of midgut EC-cells and EC-cell tumors, and its expression may be useful in the diagnosis of metastases from occult ETs.

Adult↗

PubMed2004

Different molecular profiles characterize well-differentiated endocrine tumors and poorly differentiated endocrine carcinomas of the gastroenteropancreatic tract.

PURPOSE: The molecular pathogenesis of gastroenteropancreatic endocrine tumors (ETs) is still largely unknown. The purpose of this work was a molecular characterization of 38 gastroenteropancreatic ETs with respect to the primary site and to the morphofunctional profile, pointing out useful diagnostic or prognostic molecular markers. EXPERIMENTAL DESIGN: Twenty-four well-differentiated ETs or carcinomas (WDET/Cs; 11 pancreatic, 3 gastric, and 10 intestinal) and 14 poorly differentiated endocrine carcinomas (1 pancreatic, 6 gastric, and 7 colorectal) were microallelotyped using 38 polymorphic microsatellite markers covering chromosomes 1, 3, 5q, 6, 11, 17, and 18. RESULTS: Regardless of the primary site, a significantly higher percentage of allelic imbalances (AIs) was observed in poorly differentiated endocrine carcinomas than in WDET/Cs (P = 0.012), except for 3 of 8 nonfunctioning pancreatic endocrine tumors and 1 colorectal WDEC, exhibiting multiple AIs on chromosomes 1, 3, 6, and 11. A strong positive correlation between AI percentage and Ki-67 proliferation index was detected considering both the whole series of ETs (P = 0.004) and the group of WDET/Cs alone (P = 0.011). The survival analysis showed a positive correlation between low percentage of AI and longer survival (P = 0.01). No recurrent AIs at specific chromosomal regions were identifiable with respect to the primary site. CONCLUSIONS: The malignant progression of endocrine tumors seems to be associated with complex allelotypes and chromosomal instability. Although no specific molecular markers of malignancy can be defined with certainty, the ploidy status and the degree of chromosomal derangements appear to be the most informative genetic factors with prognostic significance.

Adult↗

PubMed2004

Localization of inhibins and activins in normal endocrine cells and endocrine tumors of the gut and pancreas: an immunohistochemical and in situ hybridization study.

Activins and inhibins, which belong to the TGF beta family, are composed of different combinations of alpha-, betaA-, and betaB-subunits, resulting in inhibin A (alphabetaA), inhibin B (alphabetaB), activin A (betaAbetaA), activin B (betaBbetaB), and activin AB (betaAbetaB). They regulate several cell functions, acting as paracrine/autocrine factors. Their actions, which depend on binding to specific receptors, are also modulated by follistatin. Gastroenteropancreatic (GEP) endocrine cells and endocrine tumors (ETs) produce several growth factors, but it is not well known whether they express follistatin and the various inhibin/activin subunits. We studied their expression in 65 GEP ETs using immunohistochemistry (IHC) and in situ hybridization (ISH). The alpha-subunit and follistatin were not identified in normal GEP endocrine cells and were poorly expressed in ETs. A betaA-subunit immunoreactivity (IR) was detected in A-, G-, EC-, and GIP-cells, while betaB-chain IR was present only in D-cells. The mRNAs encoding for these molecules were poorly expressed in normal tissues. BetaA- and betaB-subunits were identified in several ETs by both IHC and ISH: betaA-subunit mainly in G-cell and A-cell ETs, and betaB-subunit in D-cell, A-cell, and EC-cell ETs. Our results demonstrate a differential expression of activin/inhibin subunits among different types of GEP endocrine cells and related tumors, suggesting a role in modulation of biological functions of these normal and neoplastic endocrine cells.

Activins↗