Giada Munari

Early miR-223 Upregulation in Gastroesophageal Carcinogenesis

Objectives To test miR-223 upregulation during gastric (intestinal-type) and Barrett esophageal carcinogenesis. Methods miR-223 expression was assessed by quantitative reverse transcription polymerase chain reaction in a series of 280 gastroesophageal biopsy samples representative of the whole spectrum of phenotypic changes involved in both carcinogenetic cascades. The results were further validated by in situ hybridization on multiple tissue specimens obtained from six surgically treated gastroesophageal adenocarcinomas. miR-223 expression was also assessed in plasma samples from 30 patients with early stage (ie, stages I and II) gastroesophageal adenocarcinoma and relative controls. Results In both gastric and esophageal models, miR-223 expression significantly increased along with the severity of the considered lesions (analysis of variance, P  <   .001). Among atrophic gastritis and long-segment Barrett esophagus samples, miR-223 overexpression was significantly associated with the score of intestinal metaplasia. miR-223 plasma levels were significantly upregulated in patients with cancer compared with controls ( t test, both P  <   .001). Conclusions miR-223 early upregulation observed in tissue samples and its diagnostic value in discriminating patients with early adenocarcinoma by plasma testing provide a solid rationale for further exploring the diagnostic reliability of this microRNA as a novel biomarker in gastroesophageal adenocarcinoma secondary prevention strategies.

Pigmented trichoblastoma developed in a sebaceous nevus: HRAS mutation as a common molecular driver

A 40-year-old woman presented with a pigmented nodule on a previously existing yellowish, verrucous plaque on the scalp. The histological diagnosis was consistent with a pigmented trichoblastoma developed within a sebaceous nevus (SN). A multigene hotspot mutational profiling of the BRAF, NRAS, HRAS and KRAS genes was carried out, and a shared G13R HRAS mutation in both the trichoblastoma and the sebaceous nevus components was found. These data support a common molecular landscape of the two lesions.

Circulating miRNAs expression profiling in drug-resistant epilepsy: Up-regulation of miR-301a-3p in a case of sudden unexpected death

Sudden and unexpected death in epilepsy (SUDEP) represents one of the most challenging fields for clinical, forensic and preventative pathology. Several authors have emphasized the search of innovative biomarkers related to drug-resistance for an appropriate risk stratification in these patients. However, no reliable biomarker has been implemented into clinical practice, so far. Herein, we present a case of SUDEP due to drug-resistant mesial temporal lobe epilepsy (MTLE) in which we performed miRNA expression profiling (miR-301a-3p, miR-194-5p, miR-30b-5p, mIR-342-5p, and miR-4446-3p) from both the plasma and the temporal lobe in comparison to ten autopsies for traumatic or asphyxia deaths. A significant up-regulation of miR-301a-3p in both the plasma (2.3 increase vs. controls) and the hippocampus (3.2-fold increase vs. controls) was evidenced, whereas the other tested miRNAs showed no significant expression differences between case and controls. Even preliminary, our results support miRNAs as an innovative class of biomarkers compatible with an adequate analysis of biospecimens obtained from forensic autopsies.

Low-grade neuroepithelial tumor: Unusual presentation in an adult without history of seizures: LGNT in an adult

Low‐grade neuroepithelial tumors (LGNT) show a broad histopathological spectrum and may be difficult to classify using current World Health Organization (WHO) criteria. A 57‐year‐old man came to medical attention because of headaches. The patient medical history was otherwise unremarkable. Magnetic resonance imaging (MRI) revealed a 2.5 cm lesion, partially cystic, with an increased signal on T2‐weighted imaging, located in the right frontal lobe. The patient underwent right frontal craniotomy and the surgical specimen was entirely evaluated. Microscopic examination showed a tumor arranged predominantly in sheets and nests, with an infiltrative growth pattern and oligodendroglioma‐like appearance. Tumor cells were round to oval with cytoplasmic clearing, hyperchromatic nuclei and inconspicuous nucleoli. Only one mitosis was identified. Necrosis was absent. Differential diagnostic considerations included oligodendroglioma, clear cell ependymoma, polymorphous low‐grade neuroepithelial tumor of the young (PLNTY) and long‐term epilepsy‐associated tumor with clear cell morphology. Neoplastic cells showed positivity for glial fibrillary acidic protein (GFAP), oligodendrocyte transcription factor 2 (OLIG2), α‐thalasemia X‐linked mental retardation syndrome (ATRX) (retained nuclear expression) and CD34. Epithelial membrane antigen (EMA), neuronal nuclear antigen, microtubule‐associated protein‐2e, cyclo‐oxygenase‐2, chromogranin A and isocitrate dehydrogenase 1 (IDH1) (R132H) were negative. Ki‐67 labeling index was 2–3%. Molecular analysis identified neither IDH1/IDH2 mutations nor 1p19q codeletion. Rapidly accelerated fibrosarcoma homolog B1 (BRAF) V600E mutation was also absent by both molecular and immunohistochemical testing. Polymerase chain reaction analysis revealed the presence of fibroblast growth factor receptor 3 (FGFR3)‐transforming acidic coiled‐coil (TACC) fusion. Taken together, the morphological, immunohistochemical and molecular findings supported the final diagnosis of PLNTY.

Assessment of intratumor immune-microenvironment in colorectal cancers with extranodal extension of nodal metastases

BackgroundNo data is available on the molecular background of the extra-nodal extension (ENE) of lymph node metastasis (LN) in colorectal cancer (CRC).MethodsA series of 22 ENE-positive CRCs was considered and three samples per case were selected (the primary CRC, an ENE-negative and an ENE-positive metastatic LN). Samples (n = 66) were analysed by immunohistochemistry for PD-L1, CD4, CD8, CD68 and CD80. Fifteen out of twenty-two cases were further profiled through a hotspot multigene mutational custom panel, including 164 hotspot regions of AKT1, APC, BRAF, CTNNB1, KIT, KRAS, NRAS, PDGFRA, PIK3CA, PTEN and TP53 genes.ResultsA significantly higher percentage of CD4-, CD8- and CD68-positive cells was observed at the invasive front of both CRCs and in ENE in contrast with what observed at the core of both CRCs and their matched nodal metastases. ENE was also characterized by a significantly higher number of CD80-positive cells. No significant difference was observed in PD-L1 distribution among the different specimens. Fourteen out of 15 CRCs (93%) showed at least a driver mutation. The most frequently mutated gene was TP53 (n = 8 tumors), followed by APC (n = 6), BRAF (n = 4), KRAS, NRAS and PIK3CA (n = 2). In 11 out of 15 CRCs (73%) the mutational profiling of the primary tumor was consistent with what obtained from the two matched LNs.ConclusionsA heterogeneous intratumor immune-microenvironment has been observed in ENE-positive CRCs, which are characterized by an increased leukocytic infiltration at the ENE invasive front.

Noncoding RNAs as drivers of the phenotypic plasticity of oesophageal mucosa

The histological commitment of the lower oesophageal mucosa largely depends on a complex molecular landscape. After extended inflammatory insult due to gastroesophageal reflux disease, squamous oesophageal mucosa may differentiate into columnar metaplastic mucosa. In this setting, the presence of intestinal metaplasia is considered the starting point of Barrett’s carcinogenetic cascade. Aside from secondary prevention strategies for Barrett’s mucosa (BM) patients, there are multiple endoscopic ablative therapies available for BM eradication and for the replacement of metaplastic epithelia with a neosquamous mucosa. However, BM frequently recurs in a few years, which supports the notable phenotypic plasticity of the oesophageal mucosa. In recent years, several reports pinpointed a class of small noncoding RNAs, the microRNAs (miRNAs), as principal effectors and regulators of oesophageal mucosa metaplastic (and neoplastic) transformation. Because of miRNAs notable stability in fixed archival diagnostic specimens, expression profiling of miRNAs represent an innovative diagnostic, prognostic and predictive tool in the stratification of phenotypic alterations in the oesophageal mucosa.