Monika Litwin1, Anna Szczepańska-Buda2, Dagmara Michałowska2, Jędrzej Grzegrzółka3, Aleksandra Piotrowska3, Agnieszka Gomułkiewicz3, Andrzej Wojnar4, Piotr Dzięgiel3,5, Wojciech Witkiewicz2. 1. Regional Specialist Hospital in Wroclaw, Research and Development Centre, Wroclaw, Poland m.litwin@cbr.novasome.pl. 2. Regional Specialist Hospital in Wroclaw, Research and Development Centre, Wroclaw, Poland. 3. Department of Histology and Embryology, Wroclaw Medical University, Wroclaw, Poland. 4. Department of Pathomorphology, Lower Silesian Oncology Centre, Wroclaw, Poland. 5. Department of Physiotherapy, University School of Physical Education, Wroclaw, Poland.
Abstract
BACKGROUND/AIM: P-Element-induced wimpy testis (PIWI) proteins in complex with PIWI-interacting RNA (piRNA) are involved in epigenetic regulation of gene expression in germline cells. Aberrant expression of piRNA and PIWI proteins have been identified in various types of tumour cells. The aim of this study was to evaluate the expression profiles of PIWI-like protein-1, -2 (PIWIL1 and PIWIL2), their immunohistochemical (IHC) characteristics in ductal breast cancer, and determine their correlation with clinicopathological parameters of this type of cancer. MATERIALS AND METHODS: Material for IHC studies comprised of 101 invasive ductal carcinoma (IDC) cases and 31 mastopathy tissues. Frozen fragments of paired tissue specimens (tumour and adjacent non-malignant breast tissue) taken from 55 patients with IDC and 18 samples of mastopathy were used for molecular studies using real-time polymerase chain reaction (RT-PCR). RESULTS: A statistically significantly higher level of PIWIL1 and PIWIL2 was found in IDC compared to mastopathy samples (p≤0.0001). Increased expression of PIWIL1 was correlated with increased PIWIL2 expression in breast cancer tissue. Surprisingly, PIWIL1 mRNA was detected only in cancer and mastopathy, but was not found in most normal breast tissues, although it is noteworthy that the PIWIL2 mRNA level was statistically significantly lower in mastopathy and IDC samples compared to normal breast tissues. CONCLUSION: Our results affirm the hypothesis that reactivation of PIWI expression in various caner types is crucial for cancer development. Copyright
BACKGROUND/AIM: P-Element-induced wimpy testis (PIWI) proteins in complex with PIWI-interacting RNA (piRNA) are involved in epigenetic regulation of gene expression in germline cells. Aberrant expression of piRNA and PIWI proteins have been identified in various types of tumour cells. The aim of this study was to evaluate the expression profiles of PIWI-like protein-1, -2 (PIWIL1 and PIWIL2), their immunohistochemical (IHC) characteristics in ductal breast cancer, and determine their correlation with clinicopathological parameters of this type of cancer. MATERIALS AND METHODS: Material for IHC studies comprised of 101 invasive ductal carcinoma (IDC) cases and 31 mastopathy tissues. Frozen fragments of paired tissue specimens (tumour and adjacent non-malignant breast tissue) taken from 55 patients with IDC and 18 samples of mastopathy were used for molecular studies using real-time polymerase chain reaction (RT-PCR). RESULTS: A statistically significantly higher level of PIWIL1 and PIWIL2 was found in IDC compared to mastopathy samples (p≤0.0001). Increased expression of PIWIL1 was correlated with increased PIWIL2 expression in breast cancer tissue. Surprisingly, PIWIL1 mRNA was detected only in cancer and mastopathy, but was not found in most normal breast tissues, although it is noteworthy that the PIWIL2 mRNA level was statistically significantly lower in mastopathy and IDC samples compared to normal breast tissues. CONCLUSION: Our results affirm the hypothesis that reactivation of PIWI expression in various caner types is crucial for cancer development. Copyright
Authors: Dan Zhang; Dawei He; Dian Li; Bo Tang; Dong Hu; Wenhao Guo; Zhang Wang; Lianju Shen; Guanghui Wei Journal: Nan Fang Yi Ke Da Xue Xue Bao Date: 2018-12-30