EGF-SNX3-EGFR axis drives tumor progression and metastasis in triple-negative breast cancers

Epidermal growth factor receptor (EGFR) has critical roles in epithelial cell physiology. Over-expression and over-activation of EGFR have been implicated in diverse cancers, including triple-negative breast cancers (TNBCs), prompting anti-EGFR therapies. Therefore, developing potent therapies and addressing the inevitable drug resistance mechanisms necessitates deciphering of EGFR related networks. Here, we describe Sorting Nexin 3 (SNX3), a member of the recycling retromer complex, as a critical player in the epidermal growth factor (EGF) stimulated EGFR network in TNBCs. We show that SNX3 is an immediate and sustained target of EGF stimulation initially at the protein level and later at the transcriptional level, causing increased SNX3 abundance. Using a proximity labeling approach, we observed increased interaction of SNX3 and EGFR upon EGF stimulation. We also detected colocalization of SNX3 with early endosomes and endocytosed EGF. Moreover, we show that EGFR protein levels are sensitive to SNX3 loss. Transient RNAi models of SNX3 downregulation have a temporary reduction in EGFR levels. In contrast, long-term silencing forces cells to recover and overexpress EGFR mRNA and protein, resulting in increased proliferation, colony formation, migration, invasion in TNBC cells, and increased tumor growth and metastasis in syngeneic models. Consistent with these results, low SNX3 and high EGFR mRNA levels correlate with poor relapse-free survival in breast cancer patients. Overall, our results suggest that SNX3 is a critical player in the EGFR network in TNBCs with implications for other cancers dependent on EGFR activity.Chemical Immunolog

Comparison of the diagnostic accuracy of next generation sequencing and microarray resequencing methods for detection of BRCA1 and BRCA2 gene mutations

Objective: Breast cancer constitutes 29 % of estimated new cases of cancer in women, and it is also one of the major cause of death in all cancer types. In this study, DNA samples of familial breast cancer patients with BRCA1 and BRCA2 mutations which had been analyzed using conventional DNA sequencing method, were also analyzed with new methods including microarray and next generation sequencing (NGS) in order to compare their results Methods: Seven patients with BRCA1 mutation, one patient with BRCA2 mutation, and two controls were included. All samples for the microarray method were studied on the GeneChip 3000 Scanner (Affymetrix) system and then analyzed on the Affymetrix GeneChip Resequencing Analysis Software (GSEQ v4.0) system. Four patients from the patient group were selected for next generation sequencing and were analyzed on GS Junior 454 (Roche, Prague, Czech Republic) system. The raw data had been analysed by SeqPilot SeqNext module (v4.0, JSI medical systems, Kippenheim, Germany). Results: Microarray resequencing analysis did not detect the mutations defined by conventional sequencing in patients, but mutations were detected in all of the 4 patients in the next generation sequencing. Conclusion: Our study detected the NGS to be reliable as conventional DNA sequencing for studying BRCA1/BRCA2 gene mutations. However, we suggest to confirm the NGS results with a conventional method because of homopolymer sequences which may cause false positive results.Gazi UniversityPublisher's Versio

A new method for analysis of whole exome sequencing data (SELIM) depending on variant prioritization

Background: After the first genome had been sequenced in 2003 with an international project, Human Genome Project, the 1000 Genomes Project also revealed the analysis of 1092 and 2504 genomes respectively. Whole exome sequencing of human samples was reported to detect approximately 20,000â30,000 SNV and indel calls on average. It is very important to choose the best tool that suits the related study. Methods: In this study, it is aimed to demonstrate the results of an in-house method (SELIM) for variant prioritization of WES data without using in-silico methods. Results: By this method, the annotated data have been decreased by 7.4â13.8 times (mean=10.9). Conclusion: By the initiation of 1.000.000 genome project, powerful databases are needed. In this respect, SELIM is an in-house workflow that can easily be used for simplifying the annotated data without using any in-silico methods. Keywords: Whole exome sequencing, Variant prioritization, Workflo

Internalized stigma in pediatric psoriasis: A comparative multicenter study

Background: Internalized stigma, adoption of negative attitudes and stereotypes of the society regarding persons' illness, has not been studied previously in pediatric psoriasis patients. Objective: We aimed to investigate the internalized stigma in pediatric psoriasis patients and to determine differences according to factors affecting internalized stigma compared to adult psoriasis patients. Methods: This multicenter, cross-sectional, comparative study included 125 pediatric (55 female, 70 male; mean age±standard deviation [SD], 14.59±2.87 years) and 1,235 adult psoriasis patients (577 female, 658 male; mean age±SD, 43.3±13.7 years). Psoriasis Internalized Stigma Scale (PISS), Dermatology Life Quality Index (DLQI), Perceived Health Status (PHS), and the General Health Questionnaire (GHQ)-12 were the scales used in the study. Results: The mean PISS was 58.48±14.9 in pediatric group. When PISS subscales of groups were compared, the pediatric group had significantly higher stigma resistance (p=0.01) whereas adult group had higher scores of alienation (p=0.01) and stereotype endorsement (p=0.04). There was a strong correlation between mean values of PISS and DLQI (r=0.423, p=0.001). High internalized stigma scores had no relation to either the severity or localization of disease in pediatric group. However, poor PHS (p=0.007) and low-income levels (p=0.03) in both groups, and body mass index (r=0.181, p=0.04) in the pediatric group were related to high PISS scores. Conclusion: Internalized stigma in pediatric patients is as high as adults and is related to poor quality of life, general health, and psychological illnesses. Unlike adults, internalized stigma was mainly determined by psoriasis per se, rather than disease severity or involvement of visible body parts, genitalia or folds. Copyright © The Korean Dermatological Association and The Korean Society for Investigative Dermatology