Epithelial to mesenchymal transition markers are associated with an increased metastatic risk in primary cutaneous squamous cell carcinomas but are attenuated in lymph node metastases

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is the second most common malignancy in humans and approximately 5% metastasize, usually to regional lymph nodes. Epithelial to mesenchymal transition (EMT) is a process involving loss of intercellular adhesion, acquisition of a mesenchymal phenotype and enhanced migratory potential; epithelial markers, such as E-cadherin, are down-regulated and mesenchymal proteins (Vimentin), increased.

OBJECTIVE

To investigate the expression of EMT markers in metastatic SCC (MSCC) and their corresponding metastases, and to correlate them with clinico-pathological factors associated with an increased risk of metastasis.

METHODS

We performed a retrospective study that included 146 cSCC samples (51 primary non-metastatic, 56 primary metastatic, 39 lymphatic metastases). Immunohistochemistry for E-cadherin, Vimentin, Snail, beta-catenin, Twist, Zeb1 and Podoplanin was performed.

RESULTS

Loss of membranous E-cadherin was observed in 77% cSCCs, with no differences between MSCC and non-MSCC. Among the transcriptional factors controlling EMT, no significant Snail1 expression was detected. Twist, Zeb1, Vimentin, beta-catenin and Podoplanin were significantly overexpressed in MSCCs. Twist ectopic expression in SCC13 cells induced Zeb1, Vimentin and Podoplanin expression and E-cadherin delocalization. These changes resulted in a scattered migration pattern in vitro. Expression of EMT markers was decreased in the metastases when compared with the corresponding primary tumors.

CONCLUSION

These results suggest that a partial EMT, characterized by the expression of Twist but without a total E-cadherin depletion, is involved in the acquisition of invasive traits by cSCC, but the process is downregulated in lymph node metastases.

D2-40 immunohistochemical overexpression in cutaneous squamous cell carcinomas: a marker of metastatic risk

BACKGROUND

Approximately 4% of cutaneous squamous cell carcinomas (cSCCs) develop lymphatic metastases. The value of lymphatic endothelial markers to enhance the detection of lymphatic tumor invasion in cSCC has not been assessed previously.

OBJECTIVE

We sought to evaluate the use of the antibody D2-40, a podoplanin immunohistochemical marker, to identify tumor lymph vessel invasion in cSCC and to assess its expression in tumor cells.

METHODS

This was a retrospective case-control study. A series of 101 cSCC, including 51 cases that developed lymphatic metastatic spread (metastasizing cSCC [MSCC]) and 50 cases that resolved definitely after surgical excision (non-MSCC) were included in the study. Lymph vessel invasion using D2-40 was evaluated on all primary biopsy specimens. The percentage of tumor cells showing D2-40 positivity and intensity scoring were recorded. All the immunohistochemical findings were correlated with the clinicopathological features.

RESULTS

Lymph vessel invasion was observed in 8% of non-MSCCs and in 25.5% of MSCCs (P = .031). D2-40 expression was significantly increased, both in intensity (odds ratio 4.42 for intensity ++/+++) and in area (odds ratio 2.29 for area >10%), in MSCC when compared with non-MSCC. Interestingly, almost half (49%) of the MSCC had moderate to intense D2-40 positivity compared with 16% of non-MSCC. D2-40 immunohistochemical expression was increased in tumors with an infiltrative pattern of extension. In the multivariate analysis, histologically poorly differentiated tumors, recurrent lesions, and cSCC showing D2-40 overexpression (in intensity) were significantly associated with lymphatic metastases development (odds ratios 15.67, 14.72, and 6.07, respectively).

LIMITATIONS

This was a retrospective study.

CONCLUSION

The expression of podoplanin associates with high metastatic risk in cSCC.

Cardiac myxoma with glandular differentiation: an immunohistochemical and ultrastructural study

A case of cardiac myxoma with glandular differentiation is reported. The patient did not have elements of the Carney triad or syndrome. The tumor was mainly composed of characteristic stellate cells in a focally collagenized, myxoid stroma, along with aggregates of glandular-forming epithelial cells, with mucin-containing intra- and intercellular lumina. Ultrastructurally, these gland spaces displayed short, straight microvilli and junctional complexes. The epithelial cells were positive for cytokeratin 7 and negative for cytokeratin 20. Calretinin was positive in the stellate cells and negative in the epithelial component. The potential origin from pluripotent mesenchymal cells or from seeded stem cells is hypothesized for glandular differentiation in myxomas. Further studies are required to unravel the relationship between stellate cells and the diverse heterologous components reported in these tumors.

CDC28 protein kinase regulatory subunit 1B (CKS1B) expression and genetic status analysis in oral squamous cell carcinoma

CKS1B is a member of the highly conserved cyclin kinase subunit 1 (CKS1) protein family which interacts with cyclin-dependent kinases and plays a critical role in cell cycle progression. In oral squamous cell carcinoma (OSCC), as in other malignancies, CKS1B overexpression has been correlated with reduced survival. To our knowledge, no studies evaluating the genetic status of CKS1B gene in OSCC have been reported. Herein, genetic and protein status of CKS1B were analyzed by immunohistochemical (IHC) and fluorescence in situ hybridization (FISH) techniques in a series of primary OSCC (n=51) and lymph node OSCC metastases samples (n=14). The observed results were compared with those obtained in either inflammatory (oral lichen planus [OLP]) (n=13) and premalignant oral mucosal lesions (oral leukoplakia) (n=16). A significant CKS1B overexpression was observed in OSCC and lymph node metastases samples than in OLP and oral leukoplakia (mean 70% vs 35%, p<0.001). CKS1B overexpression correlated with p27 loss of expression (p=0.0013) and SKP2 overexpression (p<0.00). FISH study disclosed statistical differences in both gene amplifications and gains between samples corresponding to OSCC and metastases from those of OLP and leukoplakia (p<0.001). Amplifications were present in 53% of OSCC samples and 33% of lymph node metastases vs 14% of oral leukoplakia and 0% of OLP biopsy specimens (p=0.002). Polysomies of chromosome 1 were seen in 46% of OSCC, 33% of ganglionar metastases, 14% of oral leukoplakia and 10% of OLP (p=0.036). Correlation of CKS1B over-expression and gains (both polysomies and amplifications) determined by FISH was statistically significant (p<0.001). Our results indicate that a high CKS1B expression is a common finding in primary OSCC which correlates with p27 low expression and SKP2 overexpression. This phenomenon may be due either to numerical (chromosome 1 polysomy) or structural (amplifications) CKS1B genetic abnormalities. This phenotypical and cytogenetic profile is not observed in premalignant or inflammatory oral mucosal lesions.

Epidermal growth factor receptor gene numerical aberrations are frequent events in actinic keratoses and invasive cutaneous squamous cell carcinomas

Epidermal growth factor receptor (EGFR) gene amplification and protein overexpression are common in several cancers. EGFR status has seldom been studied in cutaneous squamous carcinomas (SCCs), or their precursors, actinic keratoses (AKs). We evaluated the presence of EGFR genomic aberrations and EGFR protein overexpression in 25 AKs and 35 invasive SCCs by means of fluorescence in situ hybridization (FISH) and immunohistochemistry. EGFR numerical aberrations were detected in 52% of AKs and 77.1% of SCCs (P = 0.042). EGFR amplification was identified in 12% of AKs and 20% of SCCs. No differences regarding EGFR numerical aberrations were observed when AKs with high-grade dysplasia were compared with SCCs. A good correlation was observed between EGFR numerical aberrations and EGFR overexpression. Our results suggest that EGFR numerical aberrations occur in the early stages of epithelial carcinogenesis in skin, not playing a role in the progression from low-grade SCCs into more aggressive phenotypes.

Role of Leishmania spp. infestation in nondiagnostic cutaneous granulomatous lesions: report of a series of patients from a Western Mediterranean area

BACKGROUND

Leishmaniasis is a parasitic disease prevalent in countries of the Mediterranean area.

OBJECTIVES

The potential role of Leishmania as the aetiological factor for cutaneous granulomatous lesions in a series of patients from a Western Mediterranean area was evaluated. The practical usefulness of Leishmania-specific polymerase chain reaction (PCR) amplification and immunohistochemical techniques in skin biopsy specimens was assessed.

METHODS

Twenty-five skin biopsies diagnosed as nonspecific granulomatous dermatoses were included in the study. A panel of histopathological features was blindly evaluated by two independent observers. Only those cases showing nondiagnostic clinicopathological features and lacking demonstrable microorganisms after bacteriological, mycological or mycobacteriological cultures and specific stains (Ziehl-Neelsen, Giemsa, Gram, periodic acid-Schiff stains) were finally selected. Quantitative real-time PCR was performed in all selected samples. In available samples, immunohistochemical detection of specific Leishmania spp. antigens was also performed.

RESULTS

From the selected 25 biopsies, Leishmania spp. DNA was detected by real-time PCR in 13 cases. In seven of eight PCR-positive cases the presence of a varying density of amastigotes could also be demonstrated immunohistochemically.

CONCLUSIONS

Leishmania infection seems to be an important aetiological factor in cutaneous granulomatous lesions showing nondiagnostic features in endemic areas. In such areas, Leishmania-specific PCR amplification and/or immunohistochemical studies may be useful diagnostic tools. These techniques may be specifically indicated in the evaluation of patients showing nonspecific granulomatous inflammatory infiltrates of unknown aetiology lacking the histopathological evidence of parasites.

Analysis of gene status in cervical dysplastic lesions and squamous cell carcinoma using tissue microarrays

Cervical displasia are classified as CIN-I, CIN-II and CIN-III. It has been observed that in at least 60% of CIN-I and CIN-II, the pathology disappears spontaneously, while around 30% persist at 24 months, 10% progress to CIN-III and 1% develops as a SCC. The factors involved in the evolution of the pathology are not defined, although infection of HPV is a necessary condition, but not the only one. For this reason, the identification of genetic changes is an essential element for understanding the carcinogenic process. It can also serve as a helpful tool for identifying patients who may be susceptible to its evolution and treatment, from patients whose lesions could regress spontaneous and for whom periodic follow-ups would be enough. Fifty three cervical biopsies from patients with dysplasia and ISCC were included in the study. These biopsies were set into nine macroarrays. Eight genes and five proteins were examined in each samples (hTERT, PIK3CA, hTERC, MYC, CCND1, BCL2, ZNF217 and p16) by fluorescence in situ hybridization (FISH) and/or immunohistochemistry (IHC). The results reflected that the genetic alterations of PIK3CA, ZNF217 and CCND1 were associated with the evolution of normal tissue to CIN I, those of hTERC and ERBB with the evolution of LSIL to HSIL, those of hTERT and MYC with the evolution of CIN-II/CIN-III to ISCC, and those of BCL-2 with the inception of ISCC. With regards to proteins, the expression of MYC and CCND1 in the initial stages of the illness would help in the acquisition of the altered cellular phenotype.

Snail1 protein in the stroma as a new putative prognosis marker for colon tumours

Over-expression of Snail1 gene transcriptional repressor promotes an epithelial-to-mesenchymal transition in epithelial tumour cell lines. Expression of Snail1 RNA has been associated to the pathogenesis of a number of malignancies; however, the lack of good monoclonal antibodies against this protein has precluded a definitive analysis of Snail1 protein. In this study, we aimed to determine the expression of this transcriptional factor in colorectal tumours. Using a Snail1 well-characterized monoclonal antibody developed in our laboratories we have analyzed by immunohistochemistry a cohort of 162 human colorectal tumours. Ninety tumours (56%) showed nuclear expression in the tumoral tissue and the adjacent stroma; in 34 (21%), Snail1 was detected just in the stroma, whereas in only 4 the expression of Snail1 was detected in the tumoral tissue and the stroma was negative. No correlation was found between the presence of Snail1 in the tumour and tumour stage; however, a trend (p = 0.054) was detected when the expression of this factor in the stroma was considered. Snail1 immunoreactivity in this compartment was associated with presence of distant metastasis (p = 0.006). Moreover, expression of Snail1 in the tumor stroma correlated with lower specific survival of cancer patients (p = 0.011). Interestingly, this correlation was also detected in stage I and II tumors. Therefore, our results indicate that the presence of nuclear Snail1 immunoreactive cells in the stroma may be an informative indicator of prognosis of colon tumours especially useful in those corresponding to lower stages and identify a new marker suitable to label activated stroma in colon tumours.

Immunolocalization of androgen receptors, estrogen alpha receptors, and estrogen beta receptors in experimentally induced canine prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is an age-dependent prostatic disease affecting male humans and dogs. In dogs, the combined administration of estrogens and androgens synergistically increases prostate weight, and continued treatment leads to the development of glandular hyperplasia. The aim of the present study was to examine the immunohistochemical expression of androgen receptor (AR), estrogen receptor alpha (ER alpha), and estrogen receptor beta (ER beta) in the different cell types of the prostate gland in an experimental model. Five male beagle dogs were castrated and treated with 25 mg of 5 alpha-androstane-3 alpha and 17beta-diol and 0.25 mg 17beta-estradiol for 30 weeks. Prostate specimens were surgically obtained every 45 days (experimental stages M0 to M6: 0, 12, 18, 24, 30, and 36 weeks from the beginning of the hormonal treatment). The control group consisted of 3 noncastrated dogs treated with a vehicle, from which specimens were only taken at the time points M0, M1, M4, and M6. Immunohistochemical data revealed high AR and ER alpha expression in the epithelial and stromal cell nuclei of all the experimental and control specimens. Weak staining of the cytoplasm was observed only in epithelial cells. The suspension of hormone treatment led to a significant reduction in the expression of both receptors. On the contrary, ER beta was expressed only in epithelial cell nuclei, with no significant differences in the percentages of stained nuclei between control and hormonally treated or atrophic prostates. Results indicate that AR, ER alpha, and ER beta are differently expressed in canine prostate tissue and that they show specific expression patterns in response to the hormonal induction of BPH.

Could the truncated variant of ERBB2 be present in the squamous carcinomas of the cervix?

ERBB2, a ligand-less membrane receptor, is frequently overexpressed in a number of human tumors, contributing to uncontrolled cell proliferation. In some cases, gene amplification correlates with protein overexpression and predicts response to trastuzumab. We analyzed the expression of ERBB2 in a group of 40 patients diagnosed with infiltrating squamous cervical carcinomas (ISCC) using a microarray. Immunochemistry was performed using two different antibodies, one against the extramembrane domain and the other one for the intramembrane domain. Ten of the 40 cases included in the study could not be evaluated. Of the 30 remaining biopsies, 13 (42%) showed immunoreactivity only with the antibody against the intramembrane domain. In 5 (16.12%), both intramembrane and extramembrane immunoreactivity was observed, and 12 (40%) were negative for both antibodies. Looking at our results, we propose that, in some ISCC, there is a rupture of the ERBB2 receptor, and this event, with slight genetic amplification, could explain the unfavorable response to trastuzumab observed in some ISCC descript for some authors.

A study of Ki-67, c-erbB2 and cyclin D-1 expression in CIN-I, CIN-III and squamous cell carcinoma of the cervix

The histological criteria for cervical intraepithelial neoplastic lesions and their follow-ups have been established, but their reproducibility, specificity and sensibility are not certain. Immunohistochemical markers provide more information on each specific case, in order to facilitate its classification and, eventually, its prognosis. Using immunohistochemical techniques, this study analyzes the prognostic value of three markers (Ki-67, c-erbB2 and Cyclin D1) in cases of low grade squamous intraepithelial neoplasia (CIN-I), high grade squamous intraepithelial neoplasia (CIN-III), and infiltrating squamous cell carcinoma (SCC) taken from a group of cervical samples. In situ hybridization was performed in order to detect high-risk HPV. High risk HPV was demonstrated in 82%, 89% and 100% of the LGSIL, HGSIL and SCC cases, respectively. C-erbB2 expression was detected in 9%, 33% and 50% of the LSIL, HGSIL and SCC cases, respectively. The Ki-67 LI was 25%, 68% and 65.5% in the LGSIL, HGSIL and SCC cases, respectively. Nuclear Cyclin D1 expression was seen in 82%, 11% and 30% of the CIN-I,CIN-III and SCC cases, respectively. We observed that the cytoplasmic cyclin D1 expression increased with the severity of the lesion instead of the nuclear expression decreasing with the progression of the pathology. Nuclear and cytoplasmic Cyclin D1 expression seemed to be related to HPV high risk infection. We concluded that Cyclin D1, cerbB2 and The Ki-67 LI expression changed in relation to the severity of the lesion and that they could be helpful in making a differential diagnosis.

Expression of androgen, oestrogen alpha and beta, and progesterone receptors in the canine prostate: differences between normal, inflamed, hyperplastic and neoplastic glands

The expression of receptor for androgen (AR), oestrogen alpha and beta (ERalpha and ERbeta) and progesterone (PR) was examined immunohistochemically in canine prostate specimens (normal, hyperplastic, inflamed [prostatitis] or neoplastic). AR immunolabelling was seen in 100% of epithelial cells of normal and hyperplastic tissue, the corresponding figures for inflamed and carcinomatous tissue being 74% and 65%, respectively. ERalpha labelling was seen in 85% of epithelial cells in normal prostate glands, the corresponding figures for hyperplastic, inflamed and neoplastic glands being 35%, 22% and 12%, respectively. ERbeta labelling was seen in 85% of epithelial cells of normal glands and in about 70% of such cells in glands showing pathological changes. On the other hand, PR expression (weak) in normal glands was observed in fewer epithelial cells (44%) than in hyperplastic (70%), inflamed (62%) or neoplastic (64%) glands.

Vulvar angiomyxoma, aggressive angiomyxoma, and angiomyofibroblastoma: an immunohistochemical and ultrastructural study

To investigate the histogenetical unifying theory of a single, pluripotential primitive cell for vulvar angiomyxoma, aggresive angiomyxoma, and angiomyofibroblastoma, an optical, immunohistochemical and ultrastructural study of a superficial angiomyxoma, aggressive angiomyxoma, and angiomyofibroblastoma was performed. These three tumors showed immunohistochemical and ultrastructural overlapping features. The results of the study suggest that these three tumor entities probably arise on a common pluripotential primitive cell located around the vessels of connective tissue, which could show the capacity for modulating its penotype toward similar but distinct mature cell types.

The up-regulation profiles of p21WAF1/CIP1 and RUNX1/AML1 correlate with myometrial infiltration in endometrioid endometrial carcinoma☆

We have recently described RUNX1/AML1 up-regulation in endometrioid endometrial carcinoma (EEC), proposing that it could play a role during the initial steps of myometrial infiltration. Some cell cycle regulators, including the cyclin-dependent kinase inhibitor p21WAF1/CIP1, have been described as targets of RUNX1/AML1. In this study, we have attempted to address the question of whether RUNX1/AML1, acting both as a gene transcription activator and a repressor, depending on the context, can be correlated with the expression of p21WAF1/CIP1 in gynecologic malignancies, in particular in EEC, where the role of p21(WAF1/CIP1) remains controversial. Toward this end, we analyzed p21WAF1/CIP1 expression in a large panel of EEC samples using real-time quantitative polymerase chain reaction and tissue microarray immunohistochemistry, and evaluated the extent to which RUNX1/AML1 and p21WAF1/CIP1 interacted in the EEC samples. The strong correlation found between RUNX1/AML1 and p21WAF1/CIP1 suggested cooperation between the 2 genes in EEC, especially in those tumor samples corresponding to stage IC carcinomas, infiltrating more than 50% of the myometrium. We hypothesize that p21WAF1/CIP1 and RUNX1/AML1 interact during the initial steps of tumor dissemination in EEC, and we discuss mechanisms that could underlie myometrial infiltration and/or the promotion of an invasive phenotype.

Expression of Snail protein in tumor-stroma interface

The product of Snail gene is a repressor of E-cadherin transcription and an inductor of the epithelial-to-mesenchymal transition in several epithelial tumor cell lines. In order to examine Snail expression in animal and human tissues, we have raised a monoclonal antibody (MAb) that reacts with the regulatory domain of this protein. Analysis of murine embryos shows that Snail is expressed in extraembryonic tissues and embryonic mesoderm, in mesenchymal cells of lungs and dermis as well as in cartilage. Little reactivity was detected in adult tissues as Snail was not constitutively expressed in most mesenchymal cells. However, Snail expression was observed in activated fibroblasts involved in wound healing in mice skin. Moreover, Snail was detected in pathological conditions causing hyperstimulation of fibroblasts, such as fibromatosis. Analysis of Snail expression in tumors revealed that it was highly expressed in sarcomas and fibrosarcomas. In epithelial tumors, it presented a more limited distribution, restricted to stromal cells placed in the vicinity of the tumor and to tumoral cells in the same areas. These results demonstrate that Snail is present in activated mesenchymal cells, indicate its relevance in the communication between tumor and stroma and suggest that it can promote the conversion of carcinoma cells to stromal cells.

Clonal proliferation of cyclin D1-positive mantle lymphocytes in an asymptomatic patient: an early-stage event in the development or an indolent form of a mantle cell lymphoma?

Mantle cell lymphoma (MCL) is a B-cell neoplasm with a relatively aggressive clinical course. There is a very small subgroup of patients who present with atypical lymphocytes in peripheral blood, with or without lymphocytosis, lymphadenopathy, or splenomegaly, and with an indolent clinical course. They frequently show mutated IgV(H) genes and CD5 negativity. We report an asymptomatic elderly patient who presented with a single submandibular lymphadenopathy. The biopsy showed immunophenotype and t(11;14)(q13;q32) consistent with MCL. The abnormal lymphoid population was also detected in peripheral blood and bone marrow. The patient has remained asymptomatic for 5 years without receiving any therapy. It is uncertain whether these cases represent an early-stage event in the development or an indolent form of MCL. The existence of such asymptomatic patients with an indolent clinical course should induce a strict clinical judgment in terms of therapeutic decisions.

Up-regulation of ERM/ETV5 correlates with the degree of myometrial infiltration in endometrioid endometrial carcinoma

To elucidate alterations in gene expression in endometrioid endometrial carcinoma (EEC), differential gene expression profiling was previously described in both tumour and non-tumour contexts, and the up-regulation of the RUNX1/AML1 proto-oncogene in EEC was characterized. Among the set of genes found to be up-regulated significantly in EEC, the most relevant, ERM/ETV5, corresponds to the PEA3 subfamily and is a member of the Ets family of transcription factors that contain the Ets DNA-binding domain and are involved in matrix remodelling. In the present work, an attempt was made to characterize the expression of ERM/ETV5 in EEC throughout the process of tumourigenesis. Gene expression levels of ERM/ETV5 were quantified by real-time quantitative PCR (RT-Q-PCR) using a large panel of samples ranging from non-invasive IA to metastatic IIIA stages, and protein expression was characterized by tissue array immunohistochemistry (TMA). RT-Q-PCR validated ERM/ETV5 up-regulation in EEC and demonstrated a specific and significant increase restricted to those tumour stages associated with myometrial invasion. TMA showed that ERM/ETV5 up-regulation correlated mainly with the transition from atrophic endometrium to hyperplasia and carcinoma during tumour progression. Furthermore, ERM/ETV5 gene and protein expression levels were associated with low tumour grade. Finally, ERM/ETV5 up-regulation correlated with that of RUNX1/AML1. All of these results lead to the proposal of a co-operative role between ERM/ETV5 and RUNX1/AML1 during the early events of endometrial tumourigenesis, which may be associated with a switch to myometrial infiltration.

Large cell lymphoma-like reaction in a cervical polyp

BACKGROUND

Inflammatory lesions of the uterine cervix are very common, and although lymphomas in this location are rare, the differential diagnosis between both diseases must be considered in some cases and may be difficult to achieve.

CASE

A 37-year-old woman in good health with a cervical polyp, showing a lymphoma-like reaction with blastic appearance, which was initially interpreted as a diffuse large-cell lymphoma. The immunohistochemical and molecular studies showed the reactive origin of the lesion.

CONCLUSIONS

Immunohistochemical and molecular biology studies may be useful to dilucidate the reactive or neoplastic origin of these lesions.

CD20-Negative T-Cell-Rich B-Cell Lymphoma as a Progression of a Nodular Lymphocyte-Predominant Hodgkin's Lymphoma Treated With Rituximab

Rituximab is a chimeric anti-CD20 monoclonal antibody. It has shown efficacy in patients with B-cell non-Hodgkin lymphoma and also in CD20-positive Hodgkin lymphoma. Recently, CD20-negative tumors have been described after Rituximab therapy. We report a 34-year-old man with a history of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), treated with different chemotherapy regimens, including anthracyclines and Rituximab. After 4 years in complete remission, he developed a CD20-negative T-cell-rich B-cell lymphoma (TCRBCL) presenting as multiple lung lesions. This case shows the difficulties in the diagnosis of CD20-negative lymphomas when the number of tumor cells is low and when they are found in a predominant T-cell context. Using anti-CD79a as a B-cell marker is mandatory to overcome the difficulties in identifying these tumors. Moreover, this case illustrates the usefulness of laser capture microdissection to obtain purified cell populations for molecular studies in lymphomas with relative paucity of tumor cells, as well as the need to analyze different IgH gene regions to decrease the rate of false-negative results in PCR clonality studies.

Characterization of HER1 (c-erbB1) Status in Locally Advanced Breast Cancer Using Fluorescence in situ Hybridization and Immunohistochemistry

Epidermal growth factor receptor (EGFR) is a 170-kDa transmembrane glycoprotein encoded by the HER1 protooncogene, located at 7p12. This receptor is related to the pathogenesis of breast cancer. The aim of this study was to analyze the status of HER1 using fluorescence in situ hybridization (FISH) and immunohistochemistry in a series of 48 patients with locally advanced breast cancer (LABC). Before neoadjuvant chemotherapy, core biopsies were taken from patients with LABC and were processed into paraffin blocks. Biopsies were then studied using FISH with a HER1 probe (Vysis, Downers Grove, Ill., USA). They were also analyzed immunohistochemically using two different EGFR antibodies from DakoCytomation (Denmark, A/S) and from Zymed (San Francisco, Calif., USA). HER1 amplifications were not found, although 31% of the cases presented aneusomy of chromosome 7. Only 2 cases presented EGFR expression. LABC presented a low level of EGFR expression. HER1 amplification was not present in LABC, although the polysomy of chromosome 7 was a common finding.

A Differential Gene Expression Profile Reveals Overexpression of RUNX1/AML1 in Invasive Endometrioid Carcinoma

Endometrial carcinoma is the most common gynecological malignant disease in industrialized countries. Two clinicopathological types of endometrial carcinoma have been described, based on estrogen relation and grade: endometrioid carcinoma (EEC) and non-EEC (NEEC). Some of the molecular events that occur during the development of endometrial carcinoma have been characterized, showing a dualistic genetic model for EEC and NEEC. However, the molecular bases for endometrial tumorigenesis are not clearly elucidated. In the present work, we attempted to identify new genes that could trigger cell transformation in EEC. We analyzed the differential gene expression profile between tumoral and nontumoral endometrial specimens with cDNA array hybridization. Among the 53 genes for which expression was found to be altered in EEC, the acute myeloid leukemia proto-oncogene, RUNX1/AML1, was one of the most highly up-regulated. The gene expression levels of RUNX1/AML1 were quantified by real-time quantitative PCR, and protein levels were characterized by tissue array immunohistochemistry. Real-time quantitative PCR validated RUNX1/AML1 up-regulation in EEC and demonstrated a specific and significantly stronger up-regulation in those tumor stages associated with myometrial invasion. Furthermore, tissue array immunohistochemistry showed that RUNX1/AML1 up-regulation correlates to the process of tumorigenesis, from normal atrophic endometrium to simple and complex hyperplasia and then, on to carcinoma. These results demonstrate for the first time the up-regulation of RUNX1/AML1 in EEC correlating with the initial steps of myometrial infiltration.

Catalyzed signal amplification for cyclin D1 detection in mantle cell lymphoma

Mantle cell lymphoma is characterized by a t(11;14)(q13;q32) translocation resulting in cyclin D1 protein overexpression. Immunohistochemical detection of the latter, therefore, is a useful marker for the diagnosis of mantle cell lymphoma. Nevertheless, interpretation of results is often hampered by the weak immunoreactivity obtained with routine detection techniques. This problem can be overcome by resorting to highly sensitive catalyzed signal amplification methods based on peroxidase-catalyzed deposition of a biotinylated phenolic compound. The present study compares the results obtained with catalyzed signal amplification, labeled streptavidin biotin, and dextran polymeric conjugate (EnVision+) techniques in cyclin D1 demonstration in mantle cell lymphoma. The study was performed on formalin-fixed, paraffin-embedded archival tissue from 20 mantle cell lymphoma cases. Ten cases of small lymphocytic lymphoma and 10 instances of follicular center cell lymphoma were used as controls. Antigen retrieval was done by autoclaving under controlled pressure (2 bar) and temperature (120 degrees C) conditions. The best results were obtained after 1 minute of exposure with catalyzed signal amplification and after 6 minutes with other detection systems. Regarding cyclin D1 expression in mantle cell lymphoma cases, 17 (85%) were weakly positive and 3 (15%), moderately positive with labeled streptavidin biotin, whereas 15 (75%) were weakly positive and 5 (25%) moderately positive with EnVision+. In contrast, all 20 mantle cell lymphoma cases were strongly cyclin D1 positive with catalyzed signal amplification. No evidence of cyclin D1 immunostaining was obtained in any of the small lymphocytic lymphoma and follicular center cell lymphoma instances with any of the three methods used. In conclusion, catalyzed signal amplification methods provide a very useful tool for cyclin D1 demonstration in cases in which other immunohistochemical techniques yield inconclusive results.

Pathogenicity of Cryptococcus neoformans var. gattii in an immunocompetent mouse model

The pathogenicity of two different genomic profiles of Cryptococcus neoformans var. gattii serotype B isolated from goats that died from cryptococcal pneumonia was assessed in an experimental model of immunocompetent mice. One strain of each randomly amplified polymorphic DNA (RAPD) profile (GR52 and GR56) and three reference C. neoformans isolates representing serotypes B, D and C were used. BALB/c male mice were inoculated by the intraperitoneal route with each strain. After 4 weeks of follow-up, the animals were sacrificed and autopsy specimens of testes, liver, spleen, kidney, lungs and brain were cultured and stained for histopathology. Although spontaneous mortality was only 2% (one animal), all mice except for those inoculated with serotype C showed positive cultures in almost one organ. The strain GR52 isolated from goat showed the highest rate of positive cultures (80%) followed by serotype D (77%). Serotype B reference strain and second goat strain GR56 were both isolated from 70% of samples. Serotype C was recovered in only 33% of organs, and never from brain or lung specimens. GR52 grew abundantly from all lung cultures, and yeast cells with large capsules were seen in histopathology inside the alveoli, peribronchial vessels and interalveolar spaces. They appeared to elicit no inflammatory response. We conclude that intraperitoneally inoculated C. neoformans var. gattii shows high virulence in this immunocompetent mouse model. Strain GR52 was highest in pathogenicity and had marked lung tropism. In contrast, the serotype C reference strain showed the lowest pathogenicity and seemed not to spread outside the abdominal viscera.

Host cell-derived cardiomyocytes in sex-mismatch cardiac allografts

BACKGROUND

Mesenchymal precursor cells are able to respond to tissue signals and differentiate into a phenotype characteristic of mature cells of that tissue. We sought to investigate whether adult human cardiomyocytes can be derived from recipient precursor cells in sex-mismatched cardiac allografts.

METHODS

We studied four male patients who received hearts from female donors, and four female patients who received an allograft from a male donor. Four sex-matched transplant patients, two of each sex served as controls. Combined fluorescence in situ hybridization with probes specific for X- and Y-chromosomes and immunohistochemistry with alpha-actin was used to identify cardiac muscle cells 4 and 12 months after transplantation. Slides were examined with a fluorescence microscope to detect the presence of male cells with one X and one Y signal in the nucleus, and female cells containing two X signals.

RESULTS

Mature cardiomyocytes from the host (1-2%) were found in five endomyocardial biopsy specimens at 4 months, and in three specimens at 12 months. In addition, recipient cells negative for cytoplasmic alpha-actin were also identified (1-21% per slide). The number of infiltrating recipient cells was not associated with the degree of rejection of the sample or with the number of prior rejection episodes. Echocardiographic evaluation showed no improvement in cardiac performance in hearts from patients with more than 10% chimeric recipient cells.

CONCLUSIONS

Our data confirm the existence of mature cardiomyocytes derived from host cells, likely mesenchymal precursors, in the adult cardiac allograft in vivo.

In vitro susceptibility of Cryptococcus neoformans serotypes to GM 237354 derivative of the sordarin class

In vitro susceptibility to the sordarin derivative GM 237354 and amphotericin B were tested in a total of 190 Cryptococcus neoformans clinical isolates from different geographical areas of Spain and South American countries. Minimal inhibitory concentrations (MICs) were obtained using the NCCLS reference microbroth dilution method and analysed according the serotypes of Cr. neoformans. The MICs for amphotericin B were lower than 1.0 microg ml(-1) (MIC90% 0.5 microg ml(-1) , MIC50% 0.125 microg ml(-1)) but five isolates showed MICs of 2.0 microg ml(-1) to GM 237354 (MIC90% 1.0 microg ml(-1), MIC50% 0.5 microg ml(-1)). Cryptococcus neoformans var. gattii serotype B, was significantly less susceptible than A and AD serotypes (P = 0.047 and P = 0.022, respectively).

Changes in androgenic steroid profile due to urine contamination by microorganisms: a prospective study in the context of doping control

Urine contamination by microorganisms may affect the interpretation of urinalysis in different areas of clinical diagnosis. This is particularly relevant in doping control. A prospective study was designed to assess the effects of urine contamination by selected pathogens on the endogenous androgenic steroid profile. Pooled urine from a healthy male volunteer with standard steroid profile compared with reference values for the Caucasian population was sterilized by filtration and stored in sterile glass tubes. Aliquots were inoculated with known amounts of 15 different organisms (bacteria, fungi, and moulds) and incubated at 37 degrees C for 2 weeks. Different markers of urine contamination, such as pH, deconjugation of steroids, and metabolic by-products, were determined. Alkalization of urinary pH was not a reliable indicator of urine contamination as several organisms grew in this medium and no alteration of this parameter was found. In uncontaminated urine, less than 10% of steroid glucuronide conjugates were spontaneously hydrolyzed. Higher rates of hydrolysis for sulfate conjugates were found. An unconjugated fraction higher than 10% of the total amount of testosterone was a reliable indicator of urine contamination. However, microbial production of testosterone or epitestosterone was not detected. In contrast, a few organisms were able to synthesize 5alpha-androstanedione, 5beta-androstanedione, and androstenedione using endogenous steroids as substrates.

Serotyping of Cryptococcus neoformans isolates from clinical and environmental sources in Spain

We determined biovars and serotypes of 154 isolates of Cryptococcus neoformans from clinical and environmental sources from different areas of Spain. All clinical isolates belonged to C. neoformans var. neoformans. Serotypes showed an irregular distribution. C. neoformans var. gattii serotype B was isolated from necropsy specimens from goats with pulmonary disease.

First identification of autochthonous Cryptococcus neoformans var. gattii isloated from goats with predominantly severe pulmonary disease in Spain

Cryptococcus neoformans var. gattii is associated with Eucalyptus trees growing in various tropical and subtropical regions of the world. The identification of 13 autochthonous strains of C. neoformans var. gattii in Spain is reported. These strains were isolated from lung (10 samples), liver (1 sample), and brain (2 samples) tissue specimens from six goats suffering from predominantly severe pulmonary disease that were autopsied. The animals were members of five different herds of goats grazing in rural areas of the province of Cáceres (Extremadura, Spain). Between 1990 and 1994, there were five outbreaks, in which between 2.5 and 12% of the goats were affected. Although respiratory symptoms (pneumonia) associated with cachexia were the predominant clinical picture in all outbreaks, brain and liver involvement was also documented in three of the five outbreaks. Biotyping was performed by culturing the isolates on L-canavanine-glycine-bromothymol blue medium and testing them for the assimilation of D-proline and D-tryptophan. Serotyping by agglutination tests confirmed the characterization of all strains as C. neoformans var. gattii serotype B. This is the first confirmation of the presence of this variety in Spain, with a peculiar ability to produce severe pulmonary and systemic disease in normal goats, particularly in the form of outbreaks of pneumonia in association with cachexia.

A clinical trial on the prevention of catheter-related sepsis using a new hub model

BACKGROUND

Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub.

METHODS

Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken.

RESULTS

Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03).

CONCLUSIONS

A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.

[Study of the antimicrobial sensitivity, auxotype, serotype and plasmid analysis of 75 strains of Neisseria gonorrhoeae isolated in Barcelona]

The sensitivity of five antimicrobials (penicillin, cefoxitin, tetracycline, ceftazidime and spectinomycin) was assayed in 75 Neisseria gonorrhoeae strains, isolated from May 1986 to December 1987 in a general hospital in Barcelona. Auxotype, serotype and plasmid analysis studies were also performed on these strains. Twenty-six (34%) penicillinase-producing strains were found. 49% of the non-penicillinase-producing strains showed intermediate resistance to penicillin and 12% were resistant with MIC greater than 1 mg/1. 6% were resistant to tetracycline and cefoxitin, respectively, and all were sensitive to ceftazidime and spectinomycin. All the penicillinase-producing strains had the plasmid Africa and three of them had a diffuser plasmid of 24.5 mD. With regard to the auxotype study, most of the strains were prototrophic (38%) followed by the proline dependent ones (38%). 64% of the penicillinase-producing strains belonged to the serogroup W I, while 77% of the non-penicillinase-producing strains were in the W II/III serogroup.

Empyema caused by Kingella denitrificans and Peptostreptococcus spp. in a patient with bronchogenic carcinoma

Empyema caused by Kingella denitrificans and Peptostreptococcus spp. was diagnosed in a patient with bronchogenic carcinoma. This appears to be the third report providing evidence of a pathogenic role for K. denitrificans, and the first concerning infection in the pleural space and in a patient with underlying immunosuppressive disease. K. denitrificans should be added to the list of fastidious gram-negative bacteria associated with opportunistic infections in the compromised host.