Francesca Garbini

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.

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.

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.

NF2 gene expression in sporadic meningiomas: Relation to grades or histotypes real time-PCR study

One of the most common regions involved in the meningiomas tumorigenesis is chromosome 22q where the NF2 gene resides. The deficiency or loss of the NF2 gene product, merlin/schwannomin, plays a role in tumor development and metastatization. Conflicting results have been reported on the prognostic value of merlin in meningiomas. Several studies have indicated NF2 gene inactivation as an early tumorigenic event unrelated to the histological grade or clinical behavior. On the contrary, the NF2 gene alteration rate differs between the different histotypes. A pathogenesis independent from the NF2 gene has been suggested in meningothelial meningiomas. In the present work, we studied the NF2 gene expression through real time‐PCR (RT‐PCR) in 30 meningiomas. The average of the NF2 gene expression of all meningiomas was considered as reference value. The average of expression of WHO grade I and II meningiomas was higher than the average of all meningiomas, whereas that of WHO grade III meningiomas was lower. When we compared the NF2 gene expression in the different meningioma grades we did not note a significant difference (P = 0.698) despite the tendency to decrease from grade I to grade III. The average expression of meningothelial meningiomas was higher than the reference value, and that of non‐meningothelial meningiomas was lower. The difference in NF2 gene expression between meningothelial and non‐meningothelial meningiomas was statistically significant (P = 0.013). Our data supports the finding that alterations in NF2 gene alteration are histotype related but not grade related.

Real-time PCR analysis of RNA extracted from formalin-fixed and paraffin-embeded tissues: effects of the fixation on outcome reliability.

In many pathologic circumstances, quantitative mRNA expression levels are important for evaluation of possible genome mutations. The development of real-time polymerase chain reaction (RT-PCR) technology has facilitated the realization of nucleic acid quantification. Potentially, quantitative PCR offers a number of advantages over traditional methods because it permits the use of small amounts of genetic material. In the present study, we optimize a RNA purification technique on specimens that are formalin-fixed, paraffin-embedded and we examine prolonged formalin fixation effects on quantitative RT-PCR analysis. We compared RNA levels with 70 colic mucosa samples using the cyclooxygenase 2 gene as marker. The difference in amplification successes between formalin-fixed tissues and formalin-fixed, paraffin-embedded tissues was not statistically significant. Moreover, we compared the expression of formalin-fixed samples with the expression of each fresh tissue. Wilcoxon Mann-Whitney test shows that only the difference in the expression levels of 1- or 3-hour formalin-fixed samples is not statistically significant with respect to other fixation times. We found that the mRNA can be reliably extracted from formalin fixed, paraffin-embedded tissue sections but that prolonged formalin fixation produces different results in quantitative RT-PCR. It can be related to difference in RNA sequences length and the generation of secondary structures that are more susceptible to the prolonged formalin fixation. We suppose that the paraffin do not influence the RNA extraction yield because there are no statistical significant differences between amplification success of formalin-fixed tissues and paraffin-embedded tissues. Therefore, in relative expression quantization, we confirm that it is appropriate to use specimens with same protocols and time for formalin fixation.

Merlin Expression in Secretory Meningiomas: Evidence of an Nf2-independent Pathogenesis?: Immunohistochemical study

One of the most common chromosomal regions implicated in the meningiomas tumorigenesis is 22q12 where the neurofibromatosis 2 (NF2) gene resides. The NF2 tumor-suppressor gene encodes for the merlin/schwannomin protein, which is responsible for the inherited disease neurofibromatosis 2. NF2 gene mutations predominantly occur in transitional and fibroblastic meningiomas, whereas the meningothelial variant is less affected. Secretory meningioma is an infrequent meningioma subtype. Its most typical morphologic feature is the presence of intracytoplasmic or extracytoplasmic round hyaline, eosinophilic, and periodic acid Shiff-positive bodies in a lesion frequently otherwise classifiable as meningothelial meningioma. This study reviews the immunohistochemical merlin expression in 14 consecutive secretory meningiomas. Our purpose was to investigate if secretory meningiomas, analogous to meningothelial meningiomas, follow a molecular route of pathogenesis independent of the neurorofibromatosis 2 gene-associated pathway. All meningiomas showed positive immunocoloration involving the majority of the hyaline inclusions and secretory cells; in 12 (86%) meningiomas, a positive immunoreaction was also documented in nonsecretory tumoral cells. Our results may indicate a molecular, besides morphologic, similarity between secretory and meningothelial meningiomas: the almost constant merlin immunohistochemical expression in our series gives evidence for a possible NF2 gene-independent pathogenesis in secretory meningiomas.

Lipoastrocytoma: Case report and review of the literature

Lipoastrocytoma is an extremely rare tumor, with only six cases described. We report the case of an astrocytoma involving the upper part of the cerebellar‐pontine angle and the right portion of the clivus starting from the brainstem with a diffuse lipomatous component in a 39 year‐old man. The patient was admitted with headache of 1 years duration and diplopia over the previous 3 months. MRI revealed a ponto‐cerebellar lesion that showed irregular enhancement after contrast administration. Subtotal excision of the tumor was accomplished. Adjuvant chemotherapy and radiation therapy were not administered. Histologically the tumor showed the classical histology of low‐grade astrocytoma and a portion of the lesion was composed of lipid‐laden cells. Immunohistochemistry for glial fibrillary acid and S‐100 proteins clearly demonstrated the glial nature of these cells. Ki‐67/Mib‐1 labeling index was low (2%). The patient remains in good neurological conditions after 10 months. Our case has a benign postoperative behavior, also after subtotal excision, with restrictions due to the short follow‐up. It is important to record each new case of this rare tumor to produce a better characterization of this lesion.

Primary cerebral myxofibrosarcoma: clinical, morphologic, immunohistochemical, molecular, and ultrastructural study of an infrequent tumor in an extraordinary localization.

Herein, we describe an intracerebral primary low-grade myxofibrosarcoma occurring in a 9-year-old boy. The lesion measured 7 cm and occupied the left parieto-occipital region. A gross-total removal of the tumor was performed. Nine months later, radiologic follow-up revealed a local recurrence which was again surgically removed. The patient then underwent radiotherapy and chemotherapy. He was well and disease-free at 6 months follow-up. The tumor was composed of spindle, stellated, and multinucleated cells embedded in a myxoid background. Foci of increased cellularity, pleomorphism, and high mitotic rate were present. The tumor borders were sharply demarcated from the non-neoplastic nervous parenchyma. Immunohistochemical staining showed that the neoplastic cells were vimentine and CD34 positive. Fluorescence in-situ hybridization analyses did not show FUS and EWSR1 gene rearrangements. Primary intracranial myxofibrosarcomas are very rare (to the best of our knowledge, less than 10 published cases in the international literature). We believe each new case should be recorded to produce a better clinical, pathologic, molecular, prognostic, and therapeutic characterization of this lesion.