Francesca Castiglione

Biomechanical and angiogenic properties of tissue-engineered rat trachea using genipin cross-linked decellularized tissue

In this study, the obtainment and characterization of decellularized rat tracheal grafts are described. The detergent-enzymatic method, already used to develop bioengineered pig and human trachea scaffolds, has been applied to rat tracheae in order to obtain airway grafts suitable to be used to improve our knowledge on the process of tissue-engineered airway transplantation and regeneration. The results demonstrated that, after 9 detergent-enzymatic cycles, almost complete decellularized tracheae, retaining the hierarchical and mechanical properties of the native tissues with strong in vivo angiogenic characteristics, could be obtained. Moreover, to improve the mechanical properties of decellularized tracheae, genipin is here considered as a naturally derived cross-linking agent. The results demonstrated that the treatment increased mechanical properties, in term of secant modulus, without neither altering the pro-angiogenic properties of decellularized airway matrices or eliciting an in vivo inflammatory response.

Expression of Estrogen Receptor β in Colon Cancer Progression

Colon cancer is the most frequent neoplasia of the intestine. This pathology is the third highest cause of death from cancer with 430,000 deaths globally per year. Estrogen has also been implicated in the development and progression of colon cancer. Also sex-specific differences have been suggested to be involved in the process. Previous studies have shown the estrogen β receptor to be the dominant receptor type in normal colonic tissue and its down-regulation along with the progression of colorectal cancer. The presence of estrogen receptors and products of estrogen-related genes in the colon suggests that estrogens have direct effects on the colonic tissue. However, the specific effect of estrogens on a normal colon and the role in the colon carcinogenesis are far from clear. The aim of this study is to analyze by real-time polymerase chain reaction, the relative quantitative expression of the estrogen receptors β, β1, β2, and β5 in colon adenocarcinomas and to compare this expression with the respective in normal tissues. Moreover, we evaluate a possible correlation between estrogens receptor expressions and disease stages. Normal tissues show estrogen receptor β expression greater than pathologic tissues and the estrogen receptor β result as most expressed in the lower disease stages.

Subependymal giant cell astrocytoma (SEGA): Is it an astrocytoma? Morphological, immunohistochemical and ultrastructural study.

Subependymal giant‐cell astrocytoma (SEGA) is a rare intra‐ventricular low‐grade tumor which frequently occurs as a manifestation of tuberous sclerosis complex. The histogenesis of SEGA is controversial and its astrocytic nature has been doubted. First studies suggested the astrocytic nature of SEGA while several recent reports demonstrate its glio‐neuronal nature. In spite of this, in the recently revised WHO classification of the CNS tumors, SEGA has been still included in the group of astrocytomas. We studied nine tuberous sclerosis complex‐associated SEGAs. Patients were 1–18 years old. Eight patients (89%) had a solitary lesion located in the lateral ventricle close to of the head of the caudate nucleus, the remaining patient (11%) had two tumors, one located close to the head of the left caudate nucleus and the other in the central part of the right lateral ventricle. Histologically, tumors were composed of three types of cells: spindle, gemistocytic and ganglion‐like. Four tumors (44%) had a prominent vascularization and three (33%) showed an angiocentric pattern. Calcifications were observed in six cases (66%). By immunohistochemistry, the majority of the tumors were GFAP‐ (9; 100%), neurofilament‐ (8, 89%), neuron‐specific enolase‐ (9, 100%), and synaptophysin‐ (8; 89%) positive. Ultrastructural studies were performed on four cases. In all four there were glial cell processes filled with intermediate filaments. In one case dense core putative neurosecretory granules were appreciable. Our results emphasize the glio‐neuronal nature of SEGA. We suggest moving it into the group of mixed glio‐neuronal tumors under the denomination of subependymal giant cell tumor.

Correlation of Epidermal Growth Factor Receptor Expression with Tumor Microdensity Vessels and with Vascular Endothelial Growth Factor Expression in Ovarian Carcinoma

We analyzed in advanced ovarian serous G3 carcinoma the correlation between epidermal growth factor receptor (EGFR) overexpression and tumor angiogenesis and their relation with clinical outcome. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were statistically correlated with disease-free interval and death from disease both in univariate and multivariate analyses while EGFR expression was not correlated with clinical outcome. MVD was significantly associated with progression of disease during chemotherapy while VEGF and EGFR expression were not correlated with responsiveness to chemotherapy (Fisher’s exact test). VEGF expression was correlated with MVD (Fisher’s exact test). EGFR showed a trend to correlation with MVD. Further studies focusing on the use of angiogenesis inhibitors in addition to EGFR inhibitors on ovarian carcinoma cells may produce therapeutic strategies in the selection of tailored therapies in ovarian cancer patients.

Embryonal tumor with abundant neuropil and true rosettes: morphological, immunohistochemical, ultrastructural and molecular study of a case showing features of medulloepithelioma and areas of mesenchymal and epithelial differentiation.

Embryonal tumors are a group of malignant neoplasms that most commonly affect the pediatric population. Embryonal tumor with abundant neuropil and true rosettes is a recently recognized rare tumor. It is composed of neurocytes and undifferentiated neuroepithelial cells arranged in clusters, cords and several types of rosettes in a prominent neuropil‐rich background. We describe a new case of this tumor. The patient, a 24‐month‐old female infant, was referred to the Meyer Childrens Hospital with a history of right brachio‐crural deficit associated with occasional episodes of headache and vomiting. Computed tomography scan and MRI revealed a large bihemispheric mass. The patient underwent two consecutive surgeries. The resultant surgical resection of the tumor was macroscopically complete. The postoperative period was uneventful. On light microscopy the tumor showed a composite morphology: embryonal tumor with abundant neuropil and true rosettes (specimen from the first surgery); medulloepithelioma with mesenchymal and epithelial areas (specimen from the second surgery). The immunohistochemistry evidenced the heterogeneous (neuronal, mesenchymal and epithelial) immunoprofile of tumoral cells. By real‐time polymerase chain reaction (RT‐PCR), the PTEN gene expression in the tumor was lower than in the five non‐neoplastic brain tissues used as control. Mutation analysis did not show any variation in INI‐1 and PTEN sequence while P53 analysis showed the presence of homozygote P72R variation. Fluorescent in situ hybridization analysis showed polysomy of chromosome 2 while amplification of N‐MYC was not detected. Owing to the rarity of embryonal tumor with abundant neuropil and true rosettes, each new case should be recorded to produce a better clinical, pathological and molecular characterization of this lesion.

KRAS Mutations Testing in Colorectal Carcinoma Patients in Italy: From Guidelines to External Quality Assessment

Background Monoclonal antibodies directed against the epidermal growth factor receptor (EGFR) have been approved for the treatment of patients with metastatic colorectal carcinoma (mCRC) that do not carry KRAS mutations. Therefore, KRAS testing has become mandatory to chose the most appropriate therapy for these patients. Methodology/Principal Findings In order to guarantee the possibility for mCRC patients to receive an high quality KRAS testing in every Italian region, the Italian Association of Medical Oncology (AIOM) and the Italian Society of Pathology and Cytopathology -Italian division of the International Academy of Pathology (SIAPEC-IAP) started a program to improve KRAS testing. AIOM and SIAPEC identified a large panel of Italian medical oncologists, pathologists and molecular biologists that outlined guidelines for KRAS testing in mCRC patients. These guidelines include specific information on the target patient population, the biological material for molecular analysis, the extraction of DNA, and the methods for the mutational analysis that are summarized in this paper. Following the publication of the guidelines, the scientific societies started an external quality assessment scheme for KRAS testing. Five CRC specimens with known KRAS mutation status were sent to the 59 centers that participated to the program. The samples were validated by three referral laboratories. The participating laboratories were allowed to use their own preferred method for DNA extraction and mutational analysis and were asked to report the results within 4 weeks. The limit to pass the quality assessment was set at 100% of true responses. In the first round, only two centers did not pass (3%). The two centers were offered to participate to a second round and both centers failed again to pass. Conclusions The results of this first Italian quality assessment for KRAS testing suggest that KRAS mutational analysis is performed with good quality in the majority of Italian centers.

Liquid-based endometrial cytology: cyto-histological correlation in a population of 917 women.

Objective:  Liquid‐based cytology, because of its capacity to reduce the obscuring factors and to provide thin‐layer specimens, represents an opportunity to reevaluate endometrial cytology. In order to assess the utility of the liquid‐based method in endometrial diagnosis, we evaluated its accuracy in comparison with histology.

Liquid‐based endometrial cytology: its possible value in postmenopausal asymptomatic women

The incidence of endometrial adenocarcinoma in asymptomatic women is low. Nevertheless, some of these women might require endometrial surveillance. In this study, we evaluated the accuracy of liquid-based endometrial cytology compared to biopsy in asymptomatic postmenopausal women. Three hundred twenty women scheduled for hysteroscopy were enrolled for this study. After hysteroscopy, patients were submitted to endometrial cytology and to biopsy. Two hundred ninety-three (92%) women had sonographically thickened endometrium (>5 mm), 53 (17%) were on tamoxifen, and 16 (5%) were on hormonal substitutive treatment. The evaluation of the biopsies determined that six (2%) women had adenocarcinoma, one (<1%) had adenomatous atypical hyperplasia, and eight (3%) had simple nonatypical hyperplasia. Endometrial cytology evidenced 5 (2%) neoplastic cases, 2 (<1%) hyperplastic with atypia cases, and 25 (8%) hyperplastic without atypia cases. Two hundred twenty-two biopsies (69%) and 17 (5%) cytologies were inadequate. One adenocarcinoma and one simple nonatypical hyperplasia were underrated by cytology resulting, respectively, as atypical hyperplasia and as negative. Four cases were false positive (simple nonatypical hyperplasias on cytology, negative on biopsy). The sensitivity and specificity were estimated, respectively, at 94% and 95%; the positive and negative predictive value were estimated, respectively, at 80% and 99%. Endometrial cytology provided sufficient material more often than biopsy (P < 0.01). We suggest to introduce liquid-based endometrial cytology in the management of some subpopulations of asymptomatic postmenopausal women. Particularly, the combination of liquid-based endometrial cytology and transvaginal sonography may improve their diagnostic accuracy and reduce unnecessary more invasive and expensive procedures.

O6- Methylguanine-DNA-Methyltransferase in Recurring Anaplastic Ependymomas: PCR and Immunohistochemistry

Abstract Ependymomas are the third most common brain tumor in children. The post surgical management is controversial. There are no convincing data on an effective role for chemotherapy. O6-Methylguanine-DNA-Methyltransferase (MGMT) is a DNA repair protein considered to be a chemosensitivity predictor. Hypermethylation of the MGMT gene promoter is an important cause of MGMT inactivation. We evaluated the MGMT gene promoter methylation and the immunohistochemical MGMT protein expression in 12 recurrent anaplastic ependymomas affecting children. Our purpose was to investigate the molecular rationale of the administration of alkylating agents to children affected by recurrent anaplastic ependymomas. All ependymomas lacked MGMT promoter hypermethylation and 9 (75%) showed high MGMT protein expression (>50% tumoral cells). Differences between different recurrences in the same patient were not observed. These results may indicate MGMT as a factor of chemoresistance to alkylating drugs in anaplastic ependymomas and support the uncertainties regarding the actual benefit of chemotherapy for patients with anaplastic ependymomas.

Congenital/infantile Fibrosarcoma of the Colon: Morphologic, Immunohistochemical, Molecular, and Ultrastructural Features of a Relatively Rare Tumor in an Extraordinary Localization

Fibrosarcomas diagnosed during the early years of life are called congenital/infantile fibrosarcomas. They differ from adult fibrosarcomas because of their limited aggressive outcome. Congenital/infantile fibrosarcomas occur most frequently on the extremities. This article describes an exceptional case of colonic congenital/infantile fibrosarcoma diagnosed in a 3-day-old baby boy. It is the third intestinal congenital/infantile fibrosarcoma reported in the international literature. The lesion was radically excised. Microscopic examination revealed a densely cellular and poorly circumscribed tumor composed of spindle cells forming interlacing fascicles with herringbone appearance. Necrotic and hemorrhagic areas were appreciable. Mitotic count was 2/10 high-power fields. Immunohistochemistry revealed that the tumor cells were positive for vimentin, focally positive for h-caldesmon, and that they were negative for epithelial markers, muscular markers, S-100 protein, and CD34. The proliferation index (Mib-1) was 15%. Polymerase chain reaction demonstrated the chromosomal translocation t(12;15) (p13;q25). At the ultrastructural level, neoplastic cells had fibroblastic and myofibroblastic features. The patient underwent follow-up without adjuvant therapy. Twelve months after the surgery, he is alive and well. Given the common indolent nature of this tumor, it is important to avoid misdiagnoses with more aggressive tumors. The algorithm for the diagnosis of congenital/infantile fibrosarcoma, especially outside the usual localizations, should comprise morphologic, immunohistochemical, molecular, and ultrastructural studies.