Breast Cancer Plasticity after Chemotherapy Highlights the Need for Re-Evaluation of Subtyping in Residual Cancer and Metastatic Tissues.

This research paper presents a novel approach to identifying biomarkers that can be used to prognosticate patients with triple-negative breast cancer (TNBC) eligible for neoadjuvant therapy. The study utilized survival and RNA sequencing data from a cohort of TNBC patients and identified 276 genes whose expression was related to survival in such patients. The gene expression data were then used to classify patients into two major groups based on the presence or absence of Wingless/Integrated-pathway (Wnt-pathway) and mesenchymal (Mes) markers (Wnt/Mes). Patients with a low expression of Wnt/Mes-related genes had a favorable outcome, with no deaths observed during follow-up, while patients with a high expression of Wnt/Mes genes had a higher mortality rate of 50% within 19 months. The identified gene list could be validated and potentially used to shape treatment options for TNBC patients eligible for neoadjuvant therapy providing valuable insights into the development of more effective treatments for TNBC. Our data also showed significant variation in gene expression profiles before and after chemotherapy, with most tumors switching to a more mesenchymal/stem cell-like profile. To verify this observation, we performed an in silico analysis to classify breast cancer tumors in Prediction Analysis of Microarray 50 (PAM50) molecular classes before treatment and after treatment using gene expression data. Our findings demonstrate that following drug intervention and metastasis, certain tumors undergo a transition to alternative subtypes, resulting in diminished therapeutic efficacy. This underscores the necessity for reevaluation of patients who have experienced relapse or metastasis post-chemotherapy, with a focus on molecular subtyping. Tailoring treatment strategies based on these refined subtypes is imperative to optimize therapeutic outcomes for affected individuals.

Differential expansion of circulating human MDSC subsets in patients with cancer, infection and inflammation.

BACKGROUND: Myeloid-derived suppressor cells (MDSC) are a functional myeloid cell subset that includes myeloid cells with immune suppressive properties. The presence of MDSC has been reported in the peripheral blood of patients with several malignant and non-malignant diseases. So far, direct comparison of MDSC across different diseases and Centers is hindered by technical pitfalls and a lack of standardized methodology. To overcome this issue, we formed a network through the COST Action Mye-EUNITER (www.mye-euniter.eu) with the goal to standardize and facilitate the comparative analysis of human circulating MDSC in cancer, inflammation and infection. In this manuscript, we present the results of the multicenter study Mye-EUNITER MDSC Monitoring Initiative, that involved 13 laboratories and compared circulating MDSC subsets across multiple diseases, using a common protocol for the isolation, identification and characterization of these cells. METHODS: We developed, tested, executed and optimized a standard operating procedure for the isolation and immunophenotyping of MDSC using blood from healthy donors. We applied this procedure to the blood of almost 400 patients and controls with different solid tumors and non-malignant diseases. The latter included viral infections such as HIV and hepatitis B virus, but also psoriasis and cardiovascular disorders. RESULTS: We observed that the frequency of MDSC in healthy donors varied substantially between centers and was influenced by technical aspects such as the anticoagulant and separation method used. Expansion of polymorphonuclear (PMN)-MDSC exceeded the expansion of monocytic MDSC (M-MDSC) in five out of six solid tumors. PMN-MDSC expansion was more pronounced in cancer compared with infection and inflammation. Programmed death-ligand 1 was primarily expressed in M-MDSC and e-MDSC and was not upregulated as a consequence of disease. LOX-1 expression was confined to PMN-MDSC. CONCLUSIONS: This study provides improved technical protocols and workflows for the multi-center analysis of circulating human MDSC subsets. Application of these workflows revealed a predominant expansion of PMN-MDSC in solid tumors that exceeds expansion in chronic infection and inflammation.

Changes in hypoxia level of CT26 tumors during various stages of development and comparing different methods of hypoxia determination.

The aim of this study was to evaluate hypoxia level at various tumor developmental stages and to compare various methods of hypoxia evaluation in pre-clinical CT26 tumor model. Using three methods of hypoxia determination, we evaluated hypoxia levels during CT26 tumor development in BALB/c mice from day 4 till day 19, in 2-3 days intervals. Molecular method was based on the analysis of selected genes expression related to hypoxia (HIF1A, ANGPTL4, TGFB1, VEGFA, ERBB3, CA9) or specific for inflammation in hypoxic sites (CCL2, CCL5) at various time points after CT26 cancer cells inoculation. Imaging methods of hypoxia evaluation included: positron-emission tomography (PET) imaging using [18F]fluoromisonidazole ([18F]FMISO) and a fluorescence microscope imaging of pimonidazole (PIMO)-positive tumor areas at various time points. Our results showed that tumor hypoxia at molecular level was relatively high at early stage of tumor development as reflected by initially high HIF1A and VEGFA expression levels and their subsequent decrease. However, imaging methods (both PET and fluorescence microscopy) showed that hypoxia increased till day 14 of tumor development. Additionally, necrotic regions dominated the tumor tissue at later stages of development, decreasing the number of hypoxic areas and completely eliminating normoxic regions (observed by PET). These results showed that molecular methods of hypoxia determination are more sensitive to show changes undergoing at cellular level, however in order to measure and visualize hypoxia in the whole organ, especially at later stages of tumor development, PET is the preferred tool. Furthermore we concluded, that during development of tumor, two peaks of hypoxia occur.

The occurrence of herpes simplex viruses 1 and 2 in skin and mucosal lesions in patients with suspicion of genital herpes.

INTRODUCTION: Infection with herpes simplex viruses 1 and 2 (HSV 1 and 2 or Human herpesvirus HHV) are one of the most common infections in human. Real time PCR is a sensitive and specific method for diagnostics of HHV infections. The aim of the study was to investigate the occurrence of HHV 1 and HHV 2 DNA in patient with clinical symptoms suggesting HHV infection. METHODS: We used real time PCR to investigate swabs from genital and perianal lesions from 74 patients of the Department of Dermatology and Venereology Medical University Warsaw and of gynecological outpatient clinics in Warsaw 40 women and 34 men. RESULTS: The results were positive for HHV 2 in 25 cases (34%), for HHV 1 in 19 cases (26%) and for both viruses in 20 cases (27%). 10 samples were negative for both viruses. CONCLUSIONS: The results confirm that the main cause of symptomatic genital herpes is HHV 2, however the percentage of HHV 1 and specially of mixed HHV 1/HHV 2 infections was unexpectedly high.

[Novel multiplex real-time PCR assay for detection and differentiation of herpes simplex virus type 1 and 2 DNA]. / Wykorzystanie nowej techniki multiplex real-time PCR do wykrywania i róznicowania DNA wirusów opryszczki typu 1 i 2.

INTRODUCTION: Herpes simplex viruses type 1 and 2 are the cause of world spread multiple infections with different course and severity. The aim of this work was to design and to optimize multiplex real-time PCR assay for simultaneous detection of HSV-1 and HSV-2. The second aim of the project was to check if the designed method is laboratory useful analyzing different clinical specimens. MATERIALS AND METHODS: In this experiment primers and probes were designed to specific viral sequences: for HSV-1 to the gene of viral DNA polymerase; for HSV-2 to the UL5 sequence. For performing qPCR assay TaqMan chemistry was used. Reference strains HSV-I McIntyre and HSV-2 MS were used as a positive control. To test laboratory utility of the designed method 58 different clinical specimens were analyzed. RESULTS: Developed multiplex real-time PCR gave positive result only in the samples containing genetic material of HSV-1/2. Of the 58 clinical samples tested, 27 proved to be positive for HSV-1 and 17 for HSV-2. The 7 samples showed the presence of both types of DNA herpes simplex virus, and 7 others were found for both HSV-1 and HSV-2 negative. CONCLUSIONS: Obtained results show that the designed method is highly specific and can possibly be used to simultaneously detect and differentiate HHV-1/2. Both high specificity and very short time of analysis have great importance in diagnosing immunocompromised patients, which ought to be diagnosed quickly and effectively in order to provide appropriate treatment.