Rocco Cappellesso

Epithelial–mesenchymal transition in malignant mesothelioma

Epithelial–mesenchymal transition is a physiopathological process by which epithelial cells acquire mesenchymal shape and properties. Malignant mesothelioma is histologically characterized by the concomitant presence of epithelioid and sarcomatoid features, the latter being associated to worse prognosis, thus suggesting a role of epithelial–mesenchymal transition in this dual phenotype. We studied 109 malignant mesotheliomas (58 epithelioid, 26 sarcomatoid, and 25 biphasic) by immunohistochemistry and qRT–PCR analysis, and demonstrated a substantial switch from epithelial markers (E-cadherin, β-catenin, and cytokeratins 5/6) to mesenchymal markers (N-cadherin, vimentin, α-smooth muscle actin, Snail, Slug, Twist, ZEB1, ZEB2, S100A4, MMP2, and MMP9) through epithelioid to biphasic and sarcomatoid histotypes. In agreement with these findings, the ectopic expression of miR-205 (a repressor of ZEB1 and ZEB2 expression) in MeT-5A (mesothelial cell line), H2452 (an epithelioid malignant mesothelioma cell line) and MSTO-211H (a biphasic malignant mesothelioma cell line) not only induced a significant reduction of ZEB1 and ZEB2 and a consequent up-regulation of E-cadherin gene expression, but also inhibited migration and invasion. Moreover, miR-205 was significantly down-regulated in biphasic and sarcomatoid histotypes (qRT–PCR and in situ hybridization analyses). Collectively, our findings indicate that epithelial–mesenchymal transition has a significant part in the morphological features of malignant mesothelioma. In particular, miR-205 down-regulation correlated significantly with both a mesenchymal phenotype and a more aggressive behavior.

Molecular Typing of Lung Adenocarcinoma on Cytological Samples Using a Multigene Next Generation Sequencing Panel

Identification of driver mutations in lung adenocarcinoma has led to development of targeted agents that are already approved for clinical use or are in clinical trials. Therefore, the number of biomarkers that will be needed to assess is expected to rapidly increase. This calls for the implementation of methods probing the mutational status of multiple genes for inoperable cases, for which limited cytological or bioptic material is available. Cytology specimens from 38 lung adenocarcinomas were subjected to the simultaneous assessment of 504 mutational hotspots of 22 lung cancer-associated genes using 10 nanograms of DNA and Ion Torrent PGM next-generation sequencing. Thirty-six cases were successfully sequenced (95%). In 24/36 cases (67%) at least one mutated gene was observed, including EGFR, KRAS, PIK3CA, BRAF, TP53, PTEN, MET, SMAD4, FGFR3, STK11, MAP2K1. EGFR and KRAS mutations, respectively found in 6/36 (16%) and 10/36 (28%) cases, were mutually exclusive. Nine samples (25%) showed concurrent alterations in different genes. The next-generation sequencing test used is superior to current standard methodologies, as it interrogates multiple genes and requires limited amounts of DNA. Its applicability to routine cytology samples might allow a significant increase in the fraction of lung cancer patients eligible for personalized therapy.

Precancerous lesions in the stomach: From biology to clinical patient management

Gastric cancer is the final step in a multi-stage cascade triggered by long-standing inflammatory conditions (particularly Helicobacter pylori infection) resulting in atrophic gastritis and intestinal metaplasia: these lesions represent the cancerization field in which (intestinal-type) gastric cancer develops. Intraepithelial neoplasia is consistently recognized as the phenotypic bridge between atrophic/metaplastic lesions and invasive cancer. This paper addresses the epidemiology, pathology, molecular profiling, and clinical management of advanced precancerous gastric lesions.

The miR-17-92 microRNA cluster: a novel diagnostic tool in large B-cell malignancies.

Diffuse large B-cell lymphoma (DLBCL) can present as de novo or can arise through the transformation of many indolent lymphomas, including follicular lymphoma (FL). The morphological differentiation between germinal center-DLBCL (GC-DLBCL) and high-grade (grade 3) FL could be challenging; the accurate sub-classification of large B-cell lymphomas is mandatory in order to select the most appropriate among the new-targeted therapies. Recent expression profiling studies reported microRNAs (miRNAs) (and miR-17-92 cluster, in particular) as useful tools in differentiating DLBCL and FL. However, these preliminary results are based on cell line-derived data or did not consider grade 3 FL cases. To investigate this point, 36 cases of GC-DLBCL and 18 cases of grade 3 non-transforming FL were considered. All diagnoses were based on the World Health Organization criteria and were confirmed by clinical, histological, and immunohistochemical data. Six members of the miR-17-92 cluster (ie, miR-18b, miR-19b, miR-20a, miR-92, miR-93, and miR-106a) and two control miRNAs (ie, miR-150 and miR-210) were quantified by quantitative reverse transcription-polymerase chain reaction. All the considered miR-17-92 cluster miRNAs were significantly overexpressed in GC-DLBCL, being miR-20a and miR-106a the most dysregulated (P<0.001). Receiver operating characteristics (ROCs) analysis was used to find the optimal cut-off in distinguishing the two histotypes. The ROC estimated thresholds for miR-18b, miR-19b, miR-20a, miR-92, and miR-106a displayed a sensitivity level higher than 0.80 in achieving the GC-DLBCL diagnosis. The classification tree built on the six thresholds allowed the correct identification of 35/36 GC-DLBCL (97.2%). Profiling the miR-17-92 cluster is a promising investigative method for differentiating GC-DLBCL from high-grade FL. Subject to the validation of these findings in further larger studies; miR-17-92 cluster could represent a reliable, standardizable diagnostic tool for the sub-classification of large B-cell lymphoid neoplasm.

Programmed cell death 4 and microRNA 21 inverse expression is maintained in cells and exosomes from ovarian serous carcinoma effusions

Ovarian serous carcinoma (OSC) is a fatal gynecologic malignancy usually presenting with bilateral localization and malignant peritoneal effusion. Programmed cell death 4 (PDCD4) is a tumor suppressor gene whose expression is directly controlled by microRNA‐21 (miR‐21). Exosomes are small cell‐derived vesicles that participate in intercellular communication, delivering their cargo of molecules to specific cells. Exosomes are involved in several physiological and pathological processes including oncogenesis, immunomodulation, angiogenesis, and metastasis. The current study analyzed the expression of PDCD4 and miR‐21 in resected OSC specimens and in cells and exosomes from OSC peritoneal effusions.

Classification of non-small cell lung carcinoma in transthoracic needle specimens using microRNA expression profiling.

BACKGROUND Emerging targeted lung cancer therapies require the accurate morphologic subclassification of non-small cell lung cancer (NSCLC), even in scant and distorted specimens obtained by transthoracic needle aspiration (TTNA). MicroRNAs (miRNAs) are small noncoding genes recently reported as useful in differentiating squamous cell carcinoma (SCC) from adenocarcinoma (AD) in resected tumor specimens. We investigated their ability to do so in TTNA specimens. METHODS Smears, immunocytochemistry slides, and corresponding cell blocks of 31 NSCLC TTNA specimens were retrieved and classified as AD or SCC based on their cytologic features and immunocytochemical profiles. Data on EGFR and K-RAS mutational status were available for all cases of AD. We quantified the hsa-let-7 family and hsa-miR-205 by quantitative reverse transcription-polymerase chain reaction and compared the miRNA expression levels in AD and SCC using Student t test. RESULTS Eighteen cases were classified as AD and 13 as SCC by light microscopy and immunocytochemistry. miRNA expression profiles demonstrated considerable, statistically significant differences between AD and SCC, showing an upregulation of hsa-let-7a, hsa-let-7b, hsa-let-7c,hsa-let-7f, hsa-let-7g, hsa-let-7i, and hsa-miR-98 and a downregulation of hsa-miR-205 in AD specimens (all P < .05; t test). CONCLUSIONS Profiling the hsa-let-7 family and hsa-miR-205 is a promising method for differentiating AD from SCC, even in such small specimens as transthoracic aspirates. Subject to the validation of these findings in further, larger studies, this could prove to be a reliable, standardizable tool for the subclassification of NSCLC.

Role and accuracy of rapid on-site evaluation of CT-guided fine needle aspiration cytology of lung nodules

A. Fassina, M. Corradin, D. Zardo, R. Cappellesso, F. Corbetti and M. Fassan
Role and accuracy of rapid on‐site evaluation of CT‐guided fine needle aspiration cytology of lung nodules

The Reticulin Algorithm for Adrenocortical Tumor Diagnosis: A Multicentric Validation Study on 245 Unpublished Cases.

The pathologic diagnosis of adrenocortical carcinoma (ACC) still needs to be improved, because the renowned Weiss Score (WS) system has a poor reproducibility of some parameters and is difficult to apply in borderline cases and in ACC variants. The “reticulin algorithm” (RA) defines malignancy through an altered reticulin framework associated with 1 of the 3 following parameter: necrosis, high mitotic rate, and vascular invasion. This study aimed at validating the interobserver reproducibility of reticulin stain evaluation in an unpublished series of 245 adrenocortical tumors (61 adenomas and 184 carcinomas) from 5 Italian centers, classified according to the WS. Eight pathologists reviewed all reticulin-stained slides. After training, a second round of evaluation on discordant cases was performed 10 weeks later. The RA reclassified 67 cases (27%) as adenomas, including 44 with no reticulin alterations and 23 with an altered reticulin framework but lacking the subsequent parameters of the triad. The other 178 cases (73%) were carcinomas according to the above-mentioned criteria. A complete (8/8 pathologists) interobserver agreement was reached in 75% of cases (&kgr;=0.702), irrespective of case derivation, pathologists’ experience, and histologic variants, and was further improved when only those cases with high WS and clinically malignant behavior were considered. After the training, the overall agreement increased to 86%. We conclude that reticulin staining is a reliable technique and an easy-to-interpret system in adrenocortical tumors; moreover, it has a high interobserver reproducibility, which supports the notion of using such a method in the proposed 2-step RA approach for ACC diagnosis.

Protein Kinase CK2 Inhibition Down Modulates the NF-κB and STAT3 Survival Pathways, Enhances the Cellular Proteotoxic Stress and Synergistically Boosts the Cytotoxic Effect of Bortezomib on Multiple Myeloma and Mantle Cell Lymphoma Cells

CK2 is a pivotal pro-survival protein kinase in multiple myeloma that may likely impinge on bortezomib-regulated cellular pathways. In the present study, we investigated CK2 expression in multiple myeloma and mantle cell lymphoma, two bortezomib-responsive B cell tumors, as well as its involvement in bortezomib-induced cytotoxicity and signaling cascades potentially mediating bortezomib resistance. In both tumors, CK2 expression correlated with that of its activated targets NF-κB and STAT3 transcription factors. Bortezomib-induced proliferation arrest and apoptosis were significantly amplified by the simultaneous inhibition of CK2 with two inhibitors (CX-4945 and K27) in multiple myeloma and mantle cell lymphoma cell lines, in a model of multiple myeloma bone marrow microenvironment and in cells isolated from patients. CK2 inhibition empowered bortezomib-triggered mitochondrial-dependent cell death. Phosphorylation of NF-κB p65 on Ser529 (a CK2 target site) and rise of the levels of the endoplasmic reticulum stress kinase/endoribonuclease Ire1α were markedly reduced upon CK2 inhibition, as were STAT3 phospho Ser727 levels. On the contrary, CK2 inhibition increased phospho Ser51 eIF2α levels and enhanced the bortezomib-dependent accumulation of poly-ubiquitylated proteins and of the proteotoxic stress-associated chaperone Hsp70. Our data suggest that CK2 over expression in multiple myeloma and mantle cell lymphoma cells might sustain survival signaling cascades and can antagonize bortezomib-induced apoptosis at different levels. CK2 inhibitors could be useful in bortezomib-based combination therapies.

Autoimmune gastritis: histology phenotype and OLGA staging

Among Western populations, the declining incidence of Helicobacter pylori infection coincides with a growing clinical impact of autoimmune gastritis.