Malignant Peripheral Nerve Sheath Tumor - A Case Report

Malignant Peripheral Nerve Sheath Tumor [MPNST] is an extremely rare tumor affecting the oral cavity. It refers to sarcomas that arise from nerve or display features of neural differentiation. Here we present a case of 30-year old male patient with MPNST of right side of the mandible. There was a family history of neurotibromatosis in this case. Histologically, pleomorphic spindle cells with wavy nuclei, light stained cytoplasm, and mitotic activity were observed. The clinical presentation, radiological findings, and light microscopic findings are described in detail. The criteria for diagnosing these tumors and recent advances for diagnosis have also been highlighted

Genomic comparison of early-passage conditionally reprogrammed breast cancer cells to their corresponding primary tumors.

Conditionally reprogrammed cells (CRCs) are epithelial cells that are directly isolated from patients' specimens and propagated in vitro with feeder cells and a Rho kinase inhibitor. A number of these cells have been generated from biopsies of breast cancer patients, including ductal carcinoma in situ and invasive carcinomas. The characterization of their genomic signatures is essential to determine their ability to reflect the natural biology of their tumors of origin. In this study, we performed the genomic characterization of six newly established invasive breast cancer CRC cultures in comparison to the original patients' primary breast tumors (PBT) from which they derived. The CRCs and corresponding PBTs were simultaneously profiled by genome-wide array-CGH, targeted next generation sequencing and global miRNA expression to determine their molecular similarities in the patterns of copy number alterations (CNAs), gene mutations and miRNA expression levels, respectively. The CRCs' epithelial cells content and ploidy levels were also evaluated by flow cytometry. A similar level of CNAs was observed in the pairs of CRCs/PBTs analyzed by array-CGH, with >95% of overlap for the most frequently affected cytobands. Consistently, targeted next generation sequencing analysis showed the retention of specific somatic variants in the CRCs as present in their original PBTs. Global miRNA profiling closely clustered the CRCs with their PBTs (Pearson Correlation, ANOVA paired test, P<0.05), indicating also similarity at the miRNA expression level; the retention of tumor-specific alterations in a subset of miRNAs in the CRCs was further confirmed by qRT-PCR. These data demonstrated that the human breast cancer CRCs of this study maintained at early passages the overall copy number, gene mutations and miRNA expression patterns of their original tumors. The further characterization of these cells by other molecular and cellular phenotypes at late cell passages, are required to further expand their use as a unique and representative ex-vivo tumor model for basic science and translational breast cancer studies

Genomic profile plots of the CRCs and corresponding original PBT of five cases analyzed.

<p>Vertical lines represent chromosome numbers and blue and red peaks cytobands with gains/amplifications and loss/deletions, respectively. Plots obtained from Agilent Cytogenomics v.2.9.2.4, using the algorithm ADM2 and the threshold value of 6.0.</p

Supervised Hierarchical Clustering (SHC) analysis of the six CRCs profiled for global miRNA expression and representative of HR+/HER2- cases (cases 1, 2, 4 and 5), HER2+ (case 3) and TNBC (case 6) subtypes.

<p>Twenty-eight miRNAs were observed differentially expressed among these breast cancer subtypes (Pearson Correlation, tTest P<0.05). MiRNAs up- and down-regulated (blue) represented in yellow and blue colors, respectively.</p

Total number of copy number alterations (CNAs) observed between the CRCs and corresponding PBTs of each pair analyzed and their respective common cytobands and range of overlap (in bold CNAs with overlap >95%).

<p>Total number of copy number alterations (CNAs) observed between the CRCs and corresponding PBTs of each pair analyzed and their respective <u>common</u> cytobands and range of overlap (in bold CNAs with overlap >95%).</p

QRT-PCR analysis of a subset of paired cases of CRCs and corresponding PBTs for miRs125-5p and 423-5p (A), 661 and 3494-5p (B).

<p>No statistical difference at P value <0.05 was observed in the individual expression of these miRNAs in each of the pairs analyzed.</p

Primary breast tumor (PBT) and corresponding CRC of case 6, representative of the TNBC subtype.

<p><b>A</b>: Phase contrast image of CRC co-culture, showing the feeder cells (short arrows) and an epithelial cell colony (cobblestone cell morphology) (40x); <b>B</b>: Flow cytometry histogram showing CRC cells stained for PE/CD326 (EpCAM) (red peaks); unlabeled control (black peaks). Number of gated cells >10,000; <b>C</b>: Ploidy analysis showing a DNA index of 3.01(G1 aneuploidy yellow peak) in relation to the diploid control (Peripheral Blood Lymphocyte (PBL)—G1 diploid red peak); <b>E</b>: FFPE tissue section (40x) and <b>F</b>: tumor area microdissected for the molecular analysis (400x); <b>D</b> and <b>G</b>: Genomic profile plots of the PBT and corresponding CRC, respectively; <b>H</b>. Next generation sequencing analysis of CRCs and corresponding PBTs showing the retention of specific somatic variants on the <i>TP53</i>, <i>KDR</i>, <i>PIK3CA</i>, <i>CDKN2</i> and <i>JAK3</i> genes in the CRCs.</p

Global miRNA profiling of five pairs of CRCs and corresponding PBTs.

<p><b>A:</b> Supervised Hierarchical Clustering (SHC) analysis (Pearson Correlation, Anova P<0.05) showing close clustering for most of the paired cases based on 18 miRNAs differentially expressed (miRNAs up-and down-regulated in yellow and blue colors, respectively). <b>B:</b> Gene Distance Matrix (GDM) correlation analysis, respectively (MeV 4.9.0).</p