Probes for INS

Objective:
To investigate in situ mRNA expression of HER 2 oncogene in breast cancers with equivocal immunohistochemical results , and to explore the potential feasibility of RNAscope technique in evaluating HER2 status in breast cancers .Methods Sixty-nine FFPE samples of invasive ductal breast cancer with equivocal HER 2 immunohistochemistry results ( IHC 2+) were collected from surgical excisions from Peking Union Medical College Hospital between June 2010 and June 2013.HER2 status and in situ mRNA expression were tested by fluorescence in situ hybridization ( FISH) and RNAscope respectively using tissue microarray constructed from tumor paraffin blocks .The results of HER2 mRNA expression were scored 0 to 4 ( from low to high levels ) according to mRNA expression in 100 cancer cells .HER2 mRNA expression was evaluated in two groups of patients , with positive and negative FISH results .Results Twenty-three of the 69 samples were FISH positive, including 16 samples that were scored 4 by RNAscope (70%,16/23), 6 samples were scored 3 ( 26%,6/23 ) and one sample was scored 2 ( 4%,1/23 ) .High in situ mRNA expression (score 4 or 3) were observed in 96%of HER2 FISH positive samples.All of samples that were scored 4 by RNAscope were FISH positive .Forty-six samples were FISH negative , including 17 samples that were scored 3 by RNAscope (37%,17/46), 25 samples were scored 2 (54%,25/46), and 4 samples were scored 1 (9%,4/46).Conclusions Breast cancer with HER2 IHC 2 +could be further classified according to in situ mRNA expression status .Among them, RNAscope score of 4 could be one of the interpretation criteria for re-testing IHC 2+samples.In situ detection of HER2 mRNA may be an additional candidate method of confirmation for HER 2 gene amplification or protein overexpression , and has potential clinical utility.

Abstract

Subtype C HIV-1 is responsible for the largest proportion of people living with HIV-1 infection. However, there is limited information about the roles of the brain and its cell types as a potential sanctuary for this subtype and how the sanctuary may be affected by the administration of anti-retroviral therapy (ART). To address this issue, we collected postmortem brain tissues from ART treated HIV-1 infected Zambian individuals who experienced complete viral suppression and those who did not. Tissues from various brain compartments were collected from each individual as frozen and formalin-fixed paraffin embedded brain specimens, for detection and quantification of HIV-1 genomes and identification of the infected cell type. Genomic DNA and RNA were extracted from frozen brain tissues. The extracted DNA and RNA were then subjected to droplet digital PCR for HIV-1 quantification. RNA/DNAscope in situ hybridization (ISH) for HIV-1 was performed on formalin-fixed paraffin embedded brain tissues in conjugation with immunohistochemistry to identify the infected cell types. Droplet digital PCR revealed that HIV-1 gag DNA and RNA were detectable in half of the cases studied regardless of ART success or failure. The presence of HIV-1 lacked specific tissue compartmentalization since detection was random among various brain tissues. When combined with immunohistochemistry, RNA/DNAscope ISH demonstrated co-localization of HIV-1 DNA with CD68 expressing cells indicative of microglia or peripheral macrophage. Our study showed that brain is a potential sanctuary for subtype C HIV-1, as HIV-1 can be detected in the brain of infected individuals irrespective of ART treatment outcome and no compartmentalization of HIV-1 to specific brain compartments was evident.

We report a case of an adolescent who presented at our emergency department with acute abdominal pain. While the initial diagnosis was acute appendicitis, a secondary and coincidental diagnosis of primary HIV-1 infection was made. Concurrent and subsequent clinical and molecular biology findings form the basis of our argument that primary HIV-1 infection was the cause of acute appendicitis in this individual.