Primary extranodal diffuse large B-cell lymphomas: Many sites, many entities? Clinico-pathological, immunohistochemical and cytogenetic study of 106 cases

We analyzed the clinicopathological, immunohistochemical and cytogenetic features of 106 extranodal (EN) diffuse large B-cell lymphomas (DLBCLs) from stomach (34 cases), intestine (10), cervico-cephalic region (11), central nervous system (13), testes (21), skin (8), and miscellaneous sites (9). Hans' algorithm and the immunohistochemical double expressor score (DES) for MYC and BCL2 were applied to all cases. A subset of fifty-eight cases were analyzed with fluorescent in situ hybridization (FISH) with specific break apart probes for BCL6, MYC, BCL2, CCND1, BCL10 and MALT1 genes. Clinical records were available for all patients. The immunohistochemical study showed that, in our series of EN-DLBCLs, the Hans' subgroup and the DES differed significantly according to the site of origin. At FISH analysis, BCL6 and BCL2 were the most commonly rearranged genes in non-GC and in GC cases, respectively. Gastrointestinal lymphomas displayed the highest rate of gene rearrangements, often with MYC involvement. One testicular DLBCL showed BCL2/MYC double hit. At survival analysis, cerebral and testicular origin was associated with poor prognosis. In addition, Hans' subgroup and other immunohistochemical markers influenced patients' outcome. In conclusion, our data suggest that immunophenotypic, genetic and survival characteristics of EN-DLBCL are related to the specific primary site of the disease.

c-MYC amplification and c-myc protein expression in pancreatic acinar cell carcinomas. New insights into the molecular signature of these rare cancers

The molecular alterations of pancreatic acinar cell carcinomas (ACCs) and mixed acinar-neuroendocrine carcinomas (MANECs) are not completely understood, and the possible role of c-MYC amplification in tumor development, progression, and prognosis is not known. We have investigated c-MYC gene amplification in a series of 35 ACCs and 4 MANECs to evaluate its frequency and a possible prognostic role. Gene amplification was investigated using interphasic fluorescence in situ hybridization analysis simultaneously hybridizing c-MYC and the centromere of chromosome 8 probes. Protein expression was immunohistochemically investigated using a specific monoclonal anti-c-myc antibody. Twenty cases had clones with different polysomies of chromosome 8 in absence of c-MYC amplification, and 5 cases had one amplified clone and other clones with chromosome 8 polysomy, while the remaining 14 cases were diploid for chromosome 8 and lacked c-MYC amplification. All MANECs showed c-MYC amplification and/or polysomy which were observed in 54% pure ACCs. Six cases (15.3%) showed nuclear immunoreactivity for c-myc, but only 4/39 cases showed simultaneous c-MYC amplification/polysomy and nuclear protein expression. c-myc immunoreactivity as well as c-MYC amplification and/or chromosome 8 polysomy was not statistically associated with prognosis. Our study demonstrates that a subset of ACCs shows c-MYC alterations including gene amplification and chromosome 8 polysomy. Although they are not associated with a different prognostic signature, the fact that these alterations are present in all MANECs suggests a role in the acinar-neuroendocrine differentiation possibly involved in the pathogenesis of MANECs.

TP53 alterations in pancreatic acinar cell carcinoma: new insights into the molecular pathology of this rare cancer

The molecular alterations of pancreatic acinar cell carcinomas (ACCs) are poorly understood and have been reported as being different from those in ductal adenocarcinomas. Loss of TP53 gene function in the pathogenesis of ACCs is controversial since contradictory findings have been published. A comprehensive analysis of the different possible genetic and epigenetic mechanisms leading to TP53 alteration in ACC has never been reported and hence the role of TP53 in the pathogenesis and/or progression of ACC remains unclear. We investigated TP53 alterations in 54 tumor samples from 44 patients, including primary and metastatic ACC, using sequencing analysis, methylation-specific multiplex ligation probe amplification, fluorescence in situ hybridization, and immunohistochemistry. TP53 mutations were found in 13 % of primary ACCs and in 31 % of metastases. Primary ACCs and metastases showed the same mutational profile, with the exception of one case, characterized by a wild-type sequence in the primary carcinoma and a mutation in the corresponding metastasis. FISH analysis revealed deletion of the TP53 region in 53 % of primary ACCs and in 50 % of metastases. Promoter hypermethylation was found in one case. The molecular alterations correlated well with the immunohistochemical findings. A statistically significant association was found between the combination of mutation of one allele and loss of the other allele of TP53 and worse survival.

Aberrant DNA methylation profiles of inherited and sporadic colorectal cancer

Background

Aberrant DNA methylation has been widely investigated in sporadic colorectal carcinomas (CRCs), and extensive work has been performed to characterize different methylation profiles of CRC. Less information is available about the role of epigenetics in hereditary CRC and about the possible clinical use of epigenetic biomarkers in CRC, regardless of the etiopathogenesis. Long interspersed nucleotide element 1 (LINE-1) hypomethylation and gene-specific hypermethylation of 38 promoters were analyzed in multicenter series of 220 CRCs including 71 Lynch (Lynch colorectal cancer with microsatellite instability (LS-MSI)), 23 CRCs of patients under 40 years in which the main inherited CRC syndromes had been excluded (early-onset colorectal cancer with microsatellite stability (EO-MSS)), and 126 sporadic CRCs, comprising 28 cases with microsatellite instability (S-MSI) and 98 that were microsatellite stable (S-MSS). All tumor methylation patterns were integrated with clinico-pathological and genetic characteristics, namely chromosomal instability (CIN), TP53 loss, BRAF, and KRAS mutations.

Results

LS-MSI mainly showed absence of extensive DNA hypo- and hypermethylation. LINE-1 hypomethylation was observed in a subset of LS-MSI that were associated with the worse prognosis. Genetically, they commonly displayed G:A transition in the KRAS gene and absence of a CIN phenotype and of TP53 loss. S-MSI exhibited a specific epigenetic profile showing low rates of LINE-1 hypomethylation and extensive gene hypermethylation. S-MSI were mainly characterized by MLH1 methylation, BRAF mutation, and absence of a CIN phenotype and of TP53 loss. By contrast, S-MSS showed a high frequency of LINE-1 hypomethylation and of CIN, and they were associated with a worse prognosis. EO-MSS were a genetically and epigenetically heterogeneous group of CRCs. Like LS-MSI, some EO-MSS displayed low rates of DNA hypo- or hypermethylation and frequent G:A transitions in the KRAS gene, suggesting that a genetic syndrome might still be unrevealed in these patients. By contrast, some EO-MSS showed similar features to those observed in S-MSS, such as LINE-1 hypomethylation, CIN, and TP53 deletion. In all four classes, hypermethylation of ESR1, GATA5, and WT1 was very common.

Conclusions

Aberrant DNA methylation analysis allows the identification of different subsets of CRCs. This study confirms the potential utility of methylation tests for early detection of CRC and suggests that LINE-1 hypomethylation may be a useful prognostic marker in both sporadic and inherited CRCs.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-015-0165-2) contains supplementary material, which is available to authorized users.

Disruption of the APC gene by t(5;7) translocation in a Turcot family

Turcot syndrome (TS) refers to the combination of colorectal polyps and primary tumours of the central nervous system. TS is a heterogeneous genetic condition due to APC and/or mismatch repair germline mutations. When APC is involved the vast majority of mutations are truncating, but in approximately 20%-30% of patients with familial polyposis no germline mutation can be found. A 30-year-old Caucasian woman with a positive pedigree for TS was referred to our Genetic Counselling Service. She was negative for APC and MUTYH but showed a reciprocal balanced translocation t(5;7)(q22;p15) at chromosome analysis. FISH analysis using specific BAC probes demonstrated that 5q22 breakpoint disrupted the APC gene. Transcript analysis by MLPA and digital PCR revealed that the cytogenetic rearrangement involving the 3' end of the APC gene caused a defective expression of a truncated transcript. This result allowed cytogenetic analysis to be offered to all the other family members and segregation analysis clearly demonstrated that all the carriers were affected, whereas non-carriers did not have the polyposis. A cytogenetic approach permitted the identification of the mutation-causing disease in this family, and the segregation analysis together with the transcript study supported the pathogenetic role of this mutation. Karyotype analysis was used as a predictive test in all members of this family. This family suggests that clinically positive TS and FAP cases, which test negative with standard molecular analysis, could be easily and cost-effectively resolved by a classical and molecular cytogenetic approach.

EGFR and KRAS Mutations in ALK-Positive Lung Adenocarcinomas: Biological and Clinical Effect

INTRODUCTION

In lung adenocarcinoma (ADC), anaplastic lymphoma receptor tyrosine kinase (ALK) rearrangements are mutually exclusive with epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. However, the existence of double-positive (DP) patients have been sporadically described. We identified DP cases in therapy-naive ALK-rearranged ADC and characterized the biology of these tumors to better understand the clinical response to tyrosine kinase inhibitors (TKIs).

MATERIALS AND METHODS

We selected 42 ALK-positive ADCs from a multicentric series of 301 cases of ADCs. A mutational analysis was performed using Sanger and/or pyrosequencing to address exons 18-21 of EGFR and codons 12-13 of the KRAS gene. In addition, the KRAS and EGFR copy number was investigated using fluorescent in situ hybridization. DP patients were treated with TKIs, and their response was evaluated according to the Response Evaluation Criteria in Solid Tumors criteria.

RESULTS

Eight of 42 ALK-positive ADCs (19%) demonstrated a concomitant mutation in the EGFR (3 cases) or KRAS (5 cases) genes and were classified as DP. All DP cases displayed copy number gains in the EGFR or KRAS gene because of polysomy or gene amplification. In the latter cases, a mutant allele-specific imbalance was observed. Four patients were treated with TKIs. The 2 EGFR-mutant DP patients demonstrated a better response to crizotinib compared with erlotinib. The 2 KRAS-mutant DP patients experienced opposite responses to crizotinib.

CONCLUSION

The incidence of DP ADC is not negligible. Patients with ALK/EGFR might benefit more from crizotinib compared with erlotinib administration, although the efficacy of TKIs in patients with ALK/KRAS remains unclear. An integrated targeted therapy should be considered for patients with DP ADC.

[Case report - a dangerous intoxication after ingestion of alkyl nitrite ("poppers")]

This case report describes the inadvertent poisoning of a young man with "poppers" after having ingested an unknown amout of the drug. "Poppers" (alkyl nitrite) were made famous in the 1960s as a party drug, and during certain sexual practices, and are still in use today. The drug's inhalation leads to a short-lived rush, vasodilation and relaxtion of smooth muscles. An accidental ingestion can lead to a significant build-up of methemoglobin with dire consequences. The therapy consists of the intravenous administration of methylene blue.

Complex karyotype in a case of cutaneous lymphangiosarcoma associated with chronic lymphedema of the lower limb

Lymphangiosarcoma is a rare malignant neoplasm of endothelial cells. The term is used to describe an angiosarcoma associated with chronic lymphedema. The skin of the head and neck region is the most common site of origin. Rather few cytogenetic studies on lymphangiosarcoma are reported in the literature. We here describe a case of an 87-year-old woman, with a history of recurring lymphangitis and with an ulcerated nodular lesion of the leg. The histological diagnosis was a malignant neoplasm of vascular origin, with the morphological and immunohistochemical features of a lymphangiosarcoma. A series of antibodies (CD31, CD34, vimentin, podoplanin and HHV-8), conventional and molecular cytogenetic and Spectral Karyotyping (SKY-FISH) analyses were used to study this case. The immunohistochemical evaluation revealed that the neoplasm was positive for vimentin, CD31, CD34 and podoplanin and negative for HHV-8. The proliferation rate (Ki-67) was about 70%. Karyotype was defined using conventional cytogenetic and SKY-FISH. In addition, high-level of amplification was observed with MYC split signal probe. The morphological and immunohistochemical evaluations supported the diagnosis of lymphangiosarcoma. Moreover, the cytogenetic and molecular findings contributed towards accurately defining the karyotypic aberrations of this rare sarcoma.

APC alterations are frequently involved in the pathogenesis of acinar cell carcinoma of the pancreas, mainly through gene loss and promoter hypermethylation

Genetic and epigenetic alterations involved in the pathogenesis of pancreatic acinar cell carcinomas (ACCs) are poorly characterized, including the frequency and role of gene-specific hypermethylation, chromosome aberrations, and copy number alterations (CNAs). A subset of ACCs is known to show alterations in the APC/β-catenin pathway which includes mutations of APC gene. However, it is not known whether, in addition to mutation, loss of APC gene function can occur through alternative genetic and epigenetic mechanisms such as gene loss or promoter methylation. We investigated the global methylation profile of 34 tumor suppressor genes, CNAs of 52 chromosomal regions, and APC gene alterations (mutation, methylation, and loss) together with APC mRNA level in 45 ACCs and related peritumoral pancreatic tissues using methylation-specific multiplex ligation probe amplification (MS-MLPA), fluorescence in situ hybridization (FISH), mutation analysis, and reverse transcription-droplet digital PCR. ACCs did not show an extensive global gene hypermethylation profile. RASSF1 and APC were the only two genes frequently methylated. APC mutations were found in only 7 % of cases, while APC loss and methylation were more frequently observed (48 and 56 % of ACCs, respectively). APC mRNA low levels were found in 58 % of cases and correlated with CNAs. In conclusion, ACCs do not show extensive global gene hypermethylation. APC alterations are frequently involved in the pathogenesis of ACCs mainly through gene loss and promoter hypermethylation, along with reduction of APC mRNA levels.

Partial trisomy of chromosome 13 as a single cytogenetic abnormality in an Italian case of nasal NK/T lymphoma

Extranodal NK/T lymphoma, nasal type, is an uncommon neoplasm that occurs with a higher prevalence among Asian populations and Native American populations of Central and Southern America. In Western countries, this tumor is extremely rare, accounting for less than 1.5% of all non-Hodgkin lymphomas. Cytogenetic analyses have been performed only in a limited number of cases, mainly because of technical problems related to extensive necrosis and the scarcity of clinical samples, and these have shown complex karyotypes with no specific chromosomal translocations. Here, we report the cytogenetic characterization of a clinically aggressive nasal NK/T-cell lymphoma occurring in a 40-year-old Italian male patient, in which the sole chromosome abnormality was a partial trisomy of chromosome 13.

In situ follicular lymphoma associated with nonlymphoid malignancies

In situ follicular lymphoma (FL) is usually an incidental finding in otherwise reactive lymph node. This report describes two cases of lymph nodal in situ FL complicated by the association with nonlymphoid neoplasms. In case 1, in situ FL was discovered incidentally on a biopsy performed for an unexplained cervical lymphadenopathy 6 months after the resection of a carotid body paraganglioma. In case 2, in situ FL was detected incidentally during surgery for radical resection of prostatic carcinoma. In the lymph nodes, the in situ FL foci were characterized immunohistologically by strong coexpression of BCL2 and CD10 in the involved GCs. FISH study demonstrated BCL2 rearrangement in one of the two tested cases. These data extend the spectrum of the clinical situations that may be associated with in situ FL, but the biological and clinical significance of the association of in situ FL with nonlymphoid neoplasms deserves further investigation. Important fields of investigation should include: (1) how to approach these patients who have a risk of progression to overt lymphoma; (2) is the association of in situ FL with concurrent nonlymphoid neoplasia incidental, related to immunosuppression or to previous treatment?

Chromosome 11q23.1 is an unstable region in B-cell tumor cell lines

Chromosome 11q23 region is a frequent target of chromosome aberrations in B-cell lymphoid tumors. Here, we present the cytogenetic and molecular characterization of an amplification affecting 11q23.1 in four cell lines derived from B-cell lymphoid tumors. A minimal common region of amplification of 330 kb was identified in three cell lines using Affymetrix Human Mapping 250K arrays. When analyzed with three BAC clones, the amplifications appeared different at cytogenetic level in each cell line. Possibly affected transcripts were evaluated using tiling arrays, and validated by real time PCR. Since no effect of the amplification at the local transcription level was observed, it is possible that 11q23 amplification might mainly represent the effect of unstable chromosomal region.

Hierarchical clustering analysis of pathologic and molecular data identifies prognostically and biologically distinct groups of colorectal carcinomas

This work has evaluated the potential superiority of a morphomolecular classification based on the combination of clinicopathologic and molecular features of colorectal cancers. A cohort of 126 colorectal carcinomas was investigated by unsupervised hierarchical clustering analysis to combine 13 routinely assessed clinicopathologic features and all five molecular markers recently suggested by Jass' classification to distinguish four molecular subtypes of sporadic colorectal carcinomas. Survival analysis was assessed by a Cox proportional hazards model. A clear separation into three prognostically significant groups was identified: cluster A and cluster C were associated with good prognosis and cluster B with poor prognosis (P=0.006). Clinicopathologic and molecular features of cluster A and cluster B tumors were strongly concordant with colorectal cancer profiles characterized by microsatellite instability or by chromosomal instability, respectively. The clinicopathologic features of cluster C tumors were suggestive of a less aggressive disease than cluster B tumors. Genetically, they appeared intermediate between cluster A and cluster B tumors, as they were mainly microsatellite stable tumors showing high levels of both MGMT methylation and loss of heterozygosity. Chromosomal instability was significantly lower in cluster C than in cluster B tumors. A more accurate tumor classification should combine the prognostic power of clinicopathologic parameters with molecular biomarkers that provide information regarding the natural history of the cancer. Hierarchical clustering seems to be a useful, promising and powerful tool for further translational studies and should lead us to define a diagnostic and prognostic signature for different carcinomas.

MGMT methylation in diffuse large B-cell lymphoma: validation of quantitative methylation-specific PCR and comparison with MGMT protein expression

AIMS

(1) To validate a quantitative real time methylation specific PCR assay (MethyLight) for the detection of O6-methylguanine-DNA methyltransferase (MGMT) gene methylation status (MS) in diffuse large B-cell lymphoma (DLBCL). (2) To determine the immunohistochemical (IHC) expression of the MGMT protein and correlate it with MS. Both IHC and MethyLight results were compared with patient's outcome.

METHODS

71 patients with primary nodal DLBCL were studied. MGMT immunoreactivity was detected using a specific monoclonal antibody. The MS of MGMT gene was analysed in 52/71 DLBCL using MethyLight. A selected subset of 40 DLBCL was also analysed using qualitative methylation-specific PCR (MSP). Statistical analysis of overall survival (OS), lymphoma-specific survival (LSS) and progression free survival (PFS) was performed according to IHC and MS results.

RESULTS

19/71 DLBCLs (27%) were MGMT-negative at IHC; all were analysed, together with 33/52 MGMT-positive DLBCLs. MethyLight showed a better performance than MSP. There was a good correlation between the presence of MGMT expression and the unmethylated status; the absence of IHC expression was poorly correlated with the presence of methylation. Better OS, LSS and PFS was found in DLBCLs with MGMT gene methylation. DLBCLs not expressing MGMT at IHC showed a longer PFS.

CONCLUSIONS

The quantitative real-time methylation-specific PCR assay for the detection of MGMT gene hypermethylation has been validated for the first time in DLBCL. Immunohistochemistry seems to represent an useful preliminary test to identify unmethylated cases; MS analysis may be performed in non-immunoreactive cases to identify truly methylated DLBCLs, which bear a better prognosis.

Primary small cell neuroendocrine carcinoma of the kidney: morphological, immunohistochemical, ultrastructural, and cytogenetic study of a case and review of the literature

Poorly differentiated neuroendocrine carcinomas (PDNECs) of the kidney are extremely rare high-grade cancers accounting for only 42 cases reported in the literature. In this paper, we describe the morphological, immunohistochemical, ultrastructural, and for the first time, cytogenetic features of a renal PDNEC. In addition, we have reviewed the literature and compared the published clinicopathological data with our morphological and genetic results. The tumor arose within the kidney parenchyma and showed the typical histological features of a pure small cell PDNEC. Fluorescence in situ hybridization study demonstrated a complex chromosomal assessment indicative of a high degree of chromosome instability with gain of multiple chromosomes, loss of p53, and amplification of myc gene. These results suggest that renal PDNEC has a different genetic background to renal clear cell carcinoma, mainly characterized by the loss of the short arm of chromosome 3. Conversely, genetic alterations seem to resemble those of type 2 papillary renal cell carcinoma. The review of the literature demonstrated that PDNECs are associated with poor prognosis and that parenchymal tumors show some differences from those arising in the pelvis, in that parenchymal tumors are purely neuroendocrine while pelvic tumors are mostly mixed neuroendocrine-exocrine neoplasms.

Development of sarcomas in mice implanted with mesenchymal stem cells seeded onto bioscaffolds

Bone marrow-derived mesenchymal stem cells (MSCs) are precursors of bone, cartilage and fat tissue. MSC can also regulate the immune response. For these properties, they are tested in clinical trials for tissue repair in combination with bioscaffolds or injected as cell suspension for immunosuppressant therapy. Experimental data, however, indicate that MSC can undergo or induce a tumorigenic process in determined circumstances. We used a modified model of ectopic bone formation in mice by subcutaneously implanting porous ceramic seeded with murine MSC. In this new model, host-derived sarcomas developed when we implanted MSC/bioscaffold constructs into syngeneic and immunodeficient recipients, but not in allogeneic hosts or when MSCs were injected as cell suspensions. The bioscaffold provided a tridimensional support for MSC to aggregate, thus producing the stimulus for triggering the process eventually leading to the transformation of surrounding cells and creating a surrogate tumor stroma. The chemical and physical characteristics of the bioscaffold did not affect tumor formation; sarcomas developed either when a stiff porous ceramic was used or when the scaffold was a smooth collagen sponge. The immunoregulatory function of MSC contributed to tumor development. Implanted MSC expanded clones of CD4+CD25+ T regulatory lymphocytes that suppressed host's antitumor immune response.

Chromosomal instability in gastric mucosa-associated lymphoid tissue lymphomas: a fluorescent in situ hybridization study using a tissue microarray approach

Extranodal marginal zone B-cell lymphomas (mucosa-associated lymphoid tissue [MALT] lymphomas) of the gastrointestinal tract have been known to have characteristic chromosomal aberrations including trisomies of chromosomes 3, 12, and 18. However, knowledge of the clinical significance of cytogenetic changes in MALT lymphomas is still limited. In the present study, the frequency of the numeric and structural aberrations of the chromosomes 1, 3, 12, 18 and X and of the MALT1 gene as well as their potential clinical significance were analyzed by using fluorescent in situ hybridization on a tissue microarray containing 257 tissue samples from 203 cases of surgically resected primary gastric lymphomas including 115 cases of MALT lymphomas, 88 cases of diffuse large B-cell lymphomas (DLBCLs, 75 with an associated MALT lymphoma, so-called ex-MALT DLBCL, and 13 de novo), and 54 controls cases of Helicobacter pylori-associated chronic gastritis. Clinical follow-up information was available in 137 cases. Trisomies 1, 3, 12, and 18 were detected in 3.3%, 44.4%, 12.3%, and 19.2% of MALT lymphomas and in 11.1%, 42.2%, 26.5%, and 22.0% of ex-MALT DLBCLs, respectively. In addition, we found gains of the X chromosome in 36.4% of MALT lymphomas, in 34.5% of ex-MALT DLBCLs, and in 36.4% of de novo DLBCLs. Structural and/or numeric abnormalities of the MALT1 gene were observed in 37.0% of MALT lymphomas and in 22.2% of ex-MALT DLBCLs. In de novo DLBCL, trisomies for chromosomes 3, 12, 18, and X were found in 42.9%, 10.0%, 11.1%, and 36.4%, respectively, whereas alterations of MALT1 (namely, translocations) were found in 20.0% of the cases. An unexpected high and previously unreported gain of chromosome X in gastric MALT lymphomas was found. This tumor appears, therefore, to be a genetically unstable neoplasia. Our results point out that t(11;18) and aneuploidy may be both involved in lymphomagenesis and that at least a subset of MALT lymphomas may progress toward high-grade neoplasia.

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.

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.

Prenatal diagnosis of del(9)(p24): a sex reverse case

BACKGROUND

We report on a fetus with sex reversal and del(9)(p24) consequent to a malsegregation of a maternal balanced complex translocation involving chromosomes 7, 9 and 11.

METHODS

Fluorescence in situ hybridization (FISH) was performed in order to verify the presence of the SRY gene and the absence of DMRT1 and DMRT2 genes located in 9p24.3 region and frequently associated with sex reversal.

RESULTS AND CONCLUSIONS

The prenatal karyotype revealed an unbalanced male fetus. The postmortem examination showed a malformed fetus with female external genitalia. Lack of DMRT1-2 genes established by FISH.

Genetic and cytogenetic observations among different types of ovarian tumors are compatible with a progression model underlying ovarian tumorigenesis

In this report we present the characterization of ovarian neoplasms including benign tumors, borderline tumors, and invasive carcinomas in order to assess whether a sharing of cytogenetic abnormalities is present in all three types of tumors. A cohort of 114 newly diagnosed and untreated ovarian epithelial tumors were analyzed by cytogenetic and molecular cytogenetic approaches with probes specific for chromosome 6. Three groups of chromosome abnormalities were identified: the first group included abnormalities common to all tumor classes (losses of chromosomes 6, 8, 10, 11, 15, 16, 17, 18, 19, 20, 21, 22, and X; gains of chromosomes 1, 3, 5, and 12; 6q24 approximately qter deletions); the second group presented specific abnormalities present in malignant but not in benign tumors (losses of chromosomes 2, 7, 13, and 14; gains of chromosome 4 and chromosome markers); and the last group included abnormalities unique to invasive carcinomas (loss of chromosome 4; gains of chromosomes 2, 7, 8, 9, 10, 16, 17, 18, 19, 20, and 21; 6q16 approximately q24 deletions; rearrangements of 3p, 3q, 13q, and 21q regions). The presence of shared chromosomal alterations in all three types of ovarian neoplasms investigated in this report seems therefore to suggest a progression model for these types of tumors.

Comparative genomic hybridization analysis of hepatoblastoma reveals high frequency of X-chromosome gains and similarities between epithelial and stromal components

Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm.

Involvement of 1p36 region in two cases of adenocarcinoma of the ampulla of Vater

Cancer of the ampulla of Vater is an uncommon disease that leads to death in 60% of affected patients. There is general agreement that local spread of the tumour (T stage) is the only significant and independent prognostic factor for this cancer. Although the genetic mechanisms underlying the development of ampullary tumors are still mostly unknown because of their rarity, the genetic anomalies involved in tumor development might serve as additional prognostic markers. Cytogenetic studies may be helpful in identifying specific chromosome regions involved in these cancers. We studied two cases of poorly differentiated ampullary adenocarcinomas using conventional and molecular cytogenetics on direct preparations. The cytogenetic analysis revealed complex chromosome complements in both cases with different cell lines, rearrangements, chromosome markers, and aneuploidies. Interestingly, the involvement of the 1p36 region was a feature of both cases. The molecular studies showed an absence of high microsatellite instability (MSI) and the morphologic and immunohistochemical pattern did not suggest MSI. This study may help to characterized ampullary adenocarcinomas showing complex karyotypes, poor differentiation and poor prognosis. In these tumors, the 1p36 region may play a relevant role in the progression towards a high grade of anaplasia.

Ovule-specific MADS-box proteins have conserved protein-protein interactions in monocot and dicot plants

OsMADS13 is a rice MADS-box gene that is specifically expressed in developing ovules. The amino acid sequence of OsMADS13 shows 74% similarity to those of FLORAL BINDING PROTEIN 7 (FBP7) and FBP11, the products of two MADS-box genes that are necessary and sufficient to determine ovule identity in Petunia. To assess whether OsMADS13, the putative rice ortholog of FBP7 and FBP11, has an equivalent function, several analyses were performed. Ectopic expression of FBP7 and FBP11 in Petunia results in ectopic ovule formation on sepals and petals. Here we show that ectopic expression of OsMADS13 in rice and Arabidopsis does not result in the formation of such structures. Furthermore, ectopic expression of FBP7 and FBP11 in Arabidopsis also fails to induce ectopic ovule formation. To determine whether protein-protein interactions involving putative class D MADS-box proteins have been conserved, yeast two-hybrid assays were performed. These experiments resulted in the identification of three putative partners of OsMADS13, all of them encoded by AGL2-like genes. Interestingly the Petunia FBP7 protein also interacts with AGL2-like proteins. The evolutionary conservation of the MADS-box protein partners of these ovule-specific factors was confirmed by exchange experiments which showed that the protein partners of OsMADS13 interact with FBP7 and vice versa.

Chromosome 6 abnormalities in ovarian surface epithelial tumors of borderline malignancy suggest a genetic continuum in the progression model of ovarian neoplasms

PURPOSE

We used conventional cytogenetics, molecular cytogenetics, and molecular genetic analyses to study the pattern of allelic loss on chromosome 6q in a cohort of borderline epithelial ovarian tumors.

EXPERIMENTAL DESIGN

Fifteen tumor samples were collected from patients undergoing surgery for ovarian tumors. The tumors of borderline malignancy, classified according to the standard criteria, included 4 mucinous and 11 serous tumors. Cytogenetic and molecular cytogenetic (with yeast artificial chromosome clones from 6q26-27) studies were performed on tumor areas contiguous to those used for histological examination ensuring the appropriate sampling. Moreover loss of heterozygosity analysis was performed using PCR amplification of eight microsatellite markers mapping on 6q27 (D6S193, D6S297), 6q26 (D6S305, D6S415, D6S441), 6q21 (D6S287), 6q16 (D6S311), and 6q14 (D6S300).

RESULTS

Deletions of this chromosome arm, in particular of 6q24-27, were the most frequent lesions found in this set of tumors. In a tumor with a normal karyotype the only detectable alteration was a deletion of approximately 300 kb within the D6S149-D6S193 interval at band 6q27. This is, to date, the smallest deletion described for borderline tumors.

CONCLUSION

Alterations in the above-mentioned interval are a common finding in advanced ovarian carcinomas but also in benign ovarian cysts, implying that some tumors of borderline malignancy may arise from benign tumors and that malignant ones may evolve from tumors of borderline malignancy. Genes located in 6q27 seem to be crucial for this mechanism of early events in ovarian tumorigenesis.

Cloning and characterization of a senescence inducing and class II tumor suppressor gene in ovarian carcinoma at chromosome region 6q27

Cytogenetic, molecular and functional analysis has shown that chromosome region 6q27 harbors a senescence inducing gene and a tumor suppressor gene involved in several solid and hematologic malignancies. We have cloned at 6q27 and characterized the RNASE6PL gene which belongs to a family of cytoplasmic RNases highly conserved from plants, to man. Analysis of 55 primary ovarian tumors and several ovarian tumor cell lines indicated that the RNASE6PL gene is not mutated in tumor tissues, but its expression is significantly reduced in 30% of primary ovarian tumors and in 75% of ovarian tumor cell lines. The promoter region of the gene was unaffected in tumors cell lines. Transfection of RNASE6PL cDNA into HEY4 and SG10G ovarian tumor cell lines suppressed tumorigenicity in nude mice. When tumors were induced by RNASE6PL-transfected cells, they completely lacked expression of RNASE6PL cDNA. Tumorigenicity was suppressed also in RNASE6PL-transfected pRPcT1/H6cl2T cells, derived from a human/mouse monochromosomic hybrid carrying a human chromosome 6 deleted at 6q27. Moreover, 63.6% of HEY4 clones and 42.8% of the clones of XP12ROSV, a Xeroderma pigmentosum SV40-immortalized cell line, transfected with RNASE6PL cDNA, developed a marked senescence process during in vitro growth. We therefore propose that RNASE6PL may be a candidate for the 6q27 senescence inducing and class II tumor suppressor gene in ovarian cancer.

Ovarian metastases from colorectal carcinoma. Clinicopathologic profile, immunophenotype, and karyotype analysis

Ovarian metastases from colorectal carcinoma frequently mimic primary ovarian carcinomas. The present study was performed to identify possible criteria helpful in differential diagnosis. Twenty-three ovarian metastases from colorectal carcinomas and 23 primary ovarian carcinomas were evaluated clinicopathologically and immunostained with antigastric M1 antigen, cathepsin E, CA125, vimentin, estrogen and progesterone receptors, cytokeratins 7 and 20, and alpha-inhibin antibodies. We performed a conventional and molecular cytogenetic study on 5 ovarian metastases from colorectal carcinoma using direct preparation, Q banding techniques, and fluorescence in situ hybridization. Integration of clinicopathologic, immunohistochemical, and cytogenetic features is helpful for the differential diagnosis of metastases of colorectal carcinomas from primary ovarian carcinomas. Bilaterality, extrapelvic spreading, high mitotic index, and cytokeratin 20 immunoreactivity, and lack of M1, CA125, and cytokeratin 7 immunoreactivity favor the diagnosis of ovarian metastases from colon carcinomas. The identification of 13q gain as a peculiar, sensitive, and specific marker of colorectal carcinomas seems relevant.

A large 6q deletion is a common cytogenetic alteration in fibroadenomas, pre-malignant lesions, and carcinomas of the breast

To assess whether early breast lesions are the precursors of invasive carcinomas, three classes of breast lesions, namely benign tumors (including fibroadenomas), putative premalignant lesions (including cases of atypical hyperplasia), and invasive carcinomas, were compared at the cytogenetic and molecular cytogenetic levels. Genetic relatedness was clearly demonstrated by the sharing of several anomalies, among which 6q deletions outnumbered all of the other alterations detected. Indeed, deletions of the long arm of chromosome 6, most likely occurring in epithelial cells, were present in 83.9% of benign breast tumors, 64% of putative premalignant lesions, and 77.4% of analyzable carcinomas. Furthermore, the interval between 6q24 and qter appeared to be the common region of deletion in all three classes of breast lesions, whereas the minimal common region of deletion was 6q27-qter. Interestingly, the latter region was reported previously to be deleted in benign ovarian tumors and recently found to harbor a gene (SEN6) that is important for SV40-mediated immortalization of human cells.

The applications of FISH in tumor pathology

The current FISH technology was greatly improved during the past 10 years. A large number of cosmids and yeast (YACs), bacterial (BACs), phage P1 derived (PACs) artificial chromosomes have been rapidly mapped and are useful as probes. In parallel, methods were established to specifically "paint" entire chromosomes or chromosome segments. Using these chromosome libraries as probes, complex rearrangements and marker chromosomes can be identified irrespective of their banding pattern. Ripetitive DNA probes specific for each chromosome centromere (alpha satellite sequences), are also available and may be used to identify specific aneuploidies. The use of sensitive digital imaging systems on the basis of "colour" rather than morphology increased the improvement of new FISH techniques. In particular, colour karyotyping results in the differential colour display of all human chromosomes. Another recent development of FISH technology is comparative genome hybridization (CGH), a genome-scanning technique that allows to identify and map chromosomal and subchromosomal gains and losses. FISH techniques may be used to investigate chromosome abnormalities not only on metaphasic chromosomes but also on interphasic nuclei. Any given tissue or cell source, such as sections of frozen tumors, imprinted cells, cultured cells, paraffin-embedded sections may be hybridized. The interphasic FISH may be extremely informative in tumor pathology even if the results are dependent on a good technical quality and adequate controls.

Implementation of a multidisciplinary disease management program for heart failure patients

Institutions across the country are considering the feasibility of a disease management program for heart failure (HF) patients. Published reports suggest that such programs can save money and improve outcomes. However, the design of a disease management program can be challenging. This paper describes the structure and function of a successful disease management program for heart failure patients. The program is supported by a multidisciplinary team of nurses, pharmacists, dietitians, social workers, and physicians who approach the problem from a self care perspective. Program components include standardized educational materials, reinforcement of educational contacts, monthly support groups, and a quarterly newsletter. Existing staff built the program with few additional resources and staff. The program, which costs only approximately $330/patient for a 6 month intervention, has decreased hospital readmissions (29%) and days in the hospital (43%) significantly. (c)1999 by CHF, Inc.

Physical map of the D6S149-D6S193 region on chromosome 6Q27 and its involvement in benign surface epithelial ovarian tumours

A detailed long range restriction map of the region defined by markers D6S149 and D6S193 on chromosome 6q27 has been constructed. This was achieved by YAC cloning and contig assembling of the same region. Seven YAC clones were found to span the almost 1000 Kb region flanked by the two markers which on the genetic map resulted to be 1.9 cM apart. With some of the characterized YAC clones we undertook a molecular cytogenetic analysis of 20 benign ovarian tumors. The rationale for this was the recent mapping to a region of chromosome 6q27, flanked by markers D6281 and D6S133, of a locus for the SV40-mediated immortalization of human cells (SEN6 gene). Noteworthy we found that the the D6S149-D6S193 region (comprised in the larger D6S281-D6S133 physical interval) was altered in all samples analysed adding support to the occurrence of a immortalization step in this type of tumors.

Involvement of chromosome 6 in endometrial cancer

Cytogenetic investigation was performed on direct preparations of 15 endometrial cancers showing different histotypes. Clonal abnormalities were found in 11 out of 13 analysable cases. The modal chromosome number was near diploid in all cases. The abnormal karyotypes contained relatively simple numerical or structural aberrations in the majority of tumours. In contrast, two neoplasms with serous papillary and mixed mullerian morphological features shared multiple complex changes as well as cytogenetic evidence of intratumoral heterogeneity. The most frequent chromosome abnormality in our series of endometrial neoplasms was 6q deletion, which was detected in serous papillary, endometrioid and mixed mullerian tumours. The loss of the 6q region, which is also frequently involved in ovarian carcinoma, suggests a relationship between endometrial and ovarian cancers based on a common histogenesis.

Recurrent duplication and deletion polymorphisms on the long arm of the Y chromosome in normal males

Deletion of the 50f2/C (DYS7C) locus in interval 6 of Yq has previously been reported as a polymorphism in three males. We describe a survey of worldwide populations for further instances of this deletion. Of 859 males tested, 55 (approximately 6%) show absence of the 50f2/C locus; duplication of the locus was also detected in eight out of 595 males (approximately 1.4%). Populations having the deletion are confined to Asia, Australasia, and southern and northern Europe; of those of reasonable sample size, Finns had the highest deletion frequency (55%; n = 21). The deletions vary in size and the larger ones remove some of the RBM (RNA Binding Motif) genes, but none of the deletion males lack DAZ (Deleted in AZoospermia), a candidate gene for the azoospermia factor. On a tree of Y haplotypes, 28 deletion and eight duplication chromosomes fall into six and four haplotypic groups respectively, each of which is likely to represent an independent deletion or duplication event. Microsatellite and other haplotyping data suggest the existence of at least two further classes of deletion. Thus duplications and deletions in this region of Yq have occurred many times in human evolution, but remain useful markers for paternal lineages.

Early involvement of 6q in surface epithelial ovarian tumors

Complex karyotypes are often seen in primary surface epithelial ovarian tumors (SEOTs). Conventional cytogenetic as well as fluorescence in situ hybridization analyses coupled with loss of heterozygosity studies identified abnormalities of chromosome 6 as one of the most frequent lesions in these types of tumors. We performed cytogenetic analysis of direct preparations from 40 SEOTs, including borderline tumors and low-, intermediate-, and high-grade carcinomas to verify the frequency of chromosome 6 alterations. We also carried out fluorescence in situ hybridization analysis with a chromosome 6 library and yeast artificial chromosome clones from a region of the same chromosome (6q27). Chromosome 6 abnormalities were identified in 30 of 32 analyzable SEOTs. Twenty-five of 32 cases showed a deletion of 6q irrespective of their histological grade. We wish to underline that this is the first report proving that del(6q) was the most frequent chromosome anomaly in near-diploid SEOTs and that it was the sole anomaly observed in four SEOTs with diploid complement. Our findings suggest that abnormalities of the telomeric region of chromosome 6 (6q27) may be considered one of the earliest lesions in the pathogenesis of ovarian carcinomas.