Giulia Ercoli

miR-494-3p is a novel tumor driver of lung carcinogenesis

Lung cancer is the leading cause of tumor-related death worldwide and more efforts are needed to elucidate lung carcinogenesis. Here we investigated the expression of 641 miRNAs in lung tumorigenesis in a K-Ras(+/LSLG12Vgeo);RERTn(ert/ert) mouse model and 113 human tumors. The conserved miRNA cluster on chromosome 12qF1 was significantly and progressively upregulated during murine lung carcinogenesis. In particular, miR-494-3p expression was correlated with lung cancer progression in mice and with worse survival in lung cancer patients. Mechanistically ectopic expression of miR-494-3p in A549 lung cancer cells boosted the tumor-initiating population enhanced cancer cell motility, and increased the expression of stem cell-related genes. Importantly, miR-494-3p improved the ability of A549 cells to grow and metastasize in vivo, modulating NOTCH1 and PTEN/PI3K/AKT signaling. Overall, these data identify miR-494-3p as a key factor in lung cancer onset and progression and possible therapeutic target.

Metformin and temozolomide, a synergic option to overcome resistance in glioblastoma multiforme models

Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor with poor survival. Cytoreduction in association with radiotherapy and temozolomide (TMZ) is the standard therapy, but response is heterogeneous and life expectancy is limited. The combined use of chemotherapeutic agents with drugs targeting cell metabolism is becoming an interesting therapeutic option for cancer treatment. Here, we found that metformin (MET) enhances TMZ effect on TMZ-sensitive cell line (U251) and overcomes TMZ-resistance in T98G GBM cell line. In particular, combined-treatment modulated apoptosis by increasing Bax/Bcl-2 ratio, and reduced Reactive Oxygen Species (ROS) production. We also observed that MET associated with TMZ was able to reduce the expression of glioma stem cells (GSC) marker CD90 particularly in T98G cells but not that of CD133. In vivo experiments showed that combined treatment with TMZ and MET significantly slowed down growth of TMZ-resistant tumors but did not affect overall survival of TMZ-sensitive tumor bearing mice. In conclusion, our results showed that metformin is able to enhance TMZ effect in TMZ-resistant cell line suggesting its potential use in TMZ refractory GBM patients. However, the lack of effect on a GBM malignancy marker like CD133 requires further evaluation since it might influence response duration.

The Contrasting Role of p16Ink4A Patterns of Expression in Neuroendocrine and Non-Neuroendocrine Lung Tumors: A Comprehensive Analysis with Clinicopathologic and Molecular Correlations

Lung cancer encompasses a constellation of malignancies with no validated prognostic markers. p16Ink4A expression has been reported in different subtypes of lung cancers; however, its prognostic value is controversial. Here, we sought to investigate the clinical significance of p16Ink4A immunoexpression according to specific staining patterns and its operational implications. A total of 502 tumors, including 277 adenocarcinomas, 84 squamous cell carcinomas, 22 large cell carcinomas, 47 typical carcinoids, 12 atypical carcinoids, 28 large cell neuroendocrine carcinomas, and 32 small cell carcinomas were reviewed and subjected to immunohistochemical analysis for p16Ink4A and Ki67. The spectrum of p16Ink4A expression was annotated for each case as negative, sporadic, focal, or diffuse. Expression at immunohistochemical level showed intra-tumor homogeneity, regardless tumor histotype. Enrichments in cells expressing p16Ink4A were observed from lower- to higher-grade neuroendocrine malignancies, whereas a decrease was seen in poorly and undifferentiated non-neuroendocrine carcinomas. Tumor proliferation indices were higher in neuroendocrine tumors expressing p16Ink4A while non-neuroendocrine malignancies immunoreactive for p16Ink4A showed a decrease in Ki67-positive cells. Quantitative statistical analyses including each histotype and the p16Ink4A status confirmed the independent prognostic role of p16Ink4A expression, being a high-risk indicator in neuroendocrine tumors and a marker of good prognosis in non-neuroendocrine lung malignancies. In this study, we provide circumstantial evidence to suggest that the routinary assessment of p16Ink4A expression using a three-tiered scoring algorithm, even in a small biopsy, may constitute a reliable, reproducible, and cost-effective substrate for a more accurate risk stratification of each individual patient.

Short-term oral antibiotics treatment promotes inflammatory activation of colonic invariant natural killer T and conventional CD4+ T Cells

The gut mucosa is continuously exposed to a vast community of microorganisms, collectively defined as microbiota, establishing a mutualistic relationship with the host and contributing to shape the immune system. Gut microbiota is acquired at birth, and its composition is relatively stable during the entire adult life. Intestinal dysbiosis, defined as a microbial imbalance of gut bacterial communities, can be caused by several factors, including bacterial infections and antibiotic use, and has been associated with an increased risk to develop or exacerbate immune-mediated pathologies, such as allergic reactions, asthma, and inflammatory bowel diseases. Still, the mechanisms by which antibiotic-induced gut dysbiosis may lead to development of mucosal inflammation are still matter of debate. To this end, we aimed to evaluate the impact of antibiotic treatment on phenotype and functions of intestinal immune cell populations, including invariant natural killer T (iNKT) cells, a subset of lipid-specific T cells profoundly influenced by alterations on the commensal microbiota. To this aim, a cocktail of broad-spectrum antibiotics was administered for 2 weeks to otherwise healthy mice before re-colonization of the intestinal microbial community with oral gavage of eubiotic or dysbiotic mucosa-associated bacteria and luminal colonic content, followed or not by intestinal inflammation induction. Here. we showed that short-term antibiotic treatment alters frequency and functions of intestinal iNKT cells, even in the absence of intestinal inflammation. The presence of a dysbiotic microbiota after antibiotic treatment imprints colonic iNKT and CD4+ T cells toward a pro-inflammatory phenotype that collectively contributes to aggravate intestinal inflammation. Nonetheless, the inflammatory potential of the dysbiotic microbiota decreases over time opening the possibility to temporally intervene on the microbial composition to re-equilibrate dysbiosis, thus controlling concomitantly mucosal immune T cell activations.

Segregation and expression analyses of hyaluronan‐binding protein 2 (HABP2): insights from a large series of familial non‐medullary thyroid cancers and literature review

Recently, the G534E variant of the HABP2 gene was reported as the underlying genetic defect in a large kindred with nonsyndromic familial nonmedullary thyroid cancer (FNMTC). Nevertheless, this postulated role was not confirmed in additional cohorts. Contrasting data are also available on HABP2 expression in the thyroid.

IMP3 expression in NSCLC brain metastases demonstrates its role as a prognostic factor in non-neuroendocrine phenotypes

Brain metastases from NSCLC are associated with a poor prognosis, and local radiotherapy is the most effective therapeutic strategy. The oncofetal protein IMP3 has been studied extensively, and evidence suggests that its expression is related to shorter overall survival and a more aggressive phenotype in solid malignancies. Here, the prognostic role of IMP3 was investigated in a cohort of patients with NSCLC brain metastases in correlation with survival and tumor histotype. A series of 42 NSCLC brain metastases samples was analyzed by tissue microarray and immunohistochemical staining for IMP3. IMP3 expression was associated with shorter overall survival in the whole series and in subgroups of metastases from non-neuroendocrine pulmonary malignancies and adenocarcinoma metastases. These results indicated that IMP3 is a strong prognostic factor in non-neuroendocrine brain metastases and in particular in patients with adenocarcinoma metastases.

Implementation of an automated inclusion system for the histological analysis of murine tissue samples: A feasibility study in DSS-induced chronic colitis

Animal models are powerful tools to expand our understanding of human diseases. Histopathological evaluation of murine experimental models is often required to support further research; thus, a more rigorous evaluation of murine histological samples is strongly advocated. Indeed, the overall quality of tissue sections is critical to draw reliable and accurate conclusions. As several methodological variables may reduce the reliability of the pathological analysis, a standardization of the procedural steps required for the processing of histological murine tissues is advisable. Here, we describe a method to standardize the technical procedure from the initial preparation to the paraffin embedding of murine samples. Specifically, we have implemented an automated inclusion system, that is, the SAKURA Tissue-Tek inclusion instrument, which is routinely used for paraffin inclusion of human samples, to process murine specimens of intestinal inflammation. Colitis severity was assessed in chronically Dextran Sodium Sulphate (DSS)–treated mice by cytofluorimetric analysis of colonic cellular infiltrates, expression of inflammatory genes and histopathological analysis of tissue samples, comparing manual and automated tissue preparation systems. We here conclude that implementation of this technique can significantly increase the quality and the reliability of histopathological examination of murine tissues.

Cutaneous metastases of internal malignancies: an experience from a single institution

BackgroundCutaneous metastases represent 2% of all skin tumours. Their recognition can be challenging, as they may present with different clinical features, with consequent frequent delay and failure in diagnosis.ObjectivesTo review our series of cutaneous metastatic lesions, analyse their frequency according to patient gender, histotype, localization of the primary tumour, and site of cutaneous metastasis, and correlate this data with clinicopathological parameters.Materials & methodsWe conducted a retrospective review of all cases of cutaneous metastases from visceral neoplasms diagnosed in our dermatopathology department from July 2003 to February 2017. We registered clinical, histological, and immunohistochemical data. Additional immunohistochemical staining panels were elaborated to confirm or identify the origin of the primary tumour, or at least to specify the histological subtype.ResultsWe identified 45 histological diagnoses of cutaneous and mucocutaneous metastases. The primary tumour that was most likely to metastasize to the skin was breast cancer. Most cases of breast (89%) and lung cancer (86%) metastasized to the trunk. Of the lesions, 57.5% were nodules and 32.5% were plaques, more frequently multiple (64.4%). In 58% of cases, a metastasis was clinically suspected. Histological examination most frequently revealed an adenocarcinoma, sometimes suggestive of the site of origin.ConclusionsCutaneous metastases should be primarily considered when discrete firm painless nodules emerge rapidly. Clinicians should carefully consider infiltrated lesions of the chest in women since scleroderma and erysipelas-like presentation can be a clue for undiagnosed breast cancer.