Gene Expression Indicates Altered Immune Modulation and Signaling Pathway Activation in Ovarian Cancer Patients Resistant to Topotecan

Epithelial ovarian cancer (EOC) is one of the deadliest gynecological malignancies. Topotecan remains an essential tool in second-line therapy; even so, most patients develop resistance within a short period of time. We aimed to identify biomarkers of topotecan resistance by using gene expression signatures derived from patient specimens at surgery and available subsequent responses to therapy. Gene expression was collected for 1436 patients and 10,103 genes. Based on disease progression, patients were categorized as responders/nonresponders depending on their progression free survival (PFS) state at 9, 12, 15 and 18 months after surgery. For each gene, the median expression was compared between responders and nonresponders for two treatment regimens (chemotherapy including/excluding topotecan) with Mann-Whitney U test at each of the four different PFS cutoffs. Statistical significance was accepted in the case of p < 0.05 with a fold change (FC) 1.44. Four genes (EPB41L2, HLA-DQB1, LTF and SFRP1) were consistently overexpressed across multiple PFS cutoff times in initial tumor samples of patients with disease progression following topotecan treatment. A common theme linked to topotecan resistance was altered immune modulation. Genes associated with disease progression after systemic chemotherapy emphasize the role of the initial organization of the tumor microenvironment in therapy resistance. Our results uncover biomarkers with potential utility for patient stratification

The prognostic association of SPAG5 gene expression in breast cancer patients with systematic therapy

Background: Despite much effort on the treatment of breast cancer over the decades, a great uncertainty regarding the appropriate molecular biomarkers and optimal therapeutic strategy still exists. This research was performed to analyze the association of SPAG5 gene expression with clinicopathological factors and survival outcomes. Methods: We used a breast cancer database including 5667 patients with a mean follow-up of 69 months. Kaplan-Meier survival analyses for relapse free survival (RFS), overall survival (OS), and distant metastasis-free survival (DMFS) were performed. In addition, ROC analysis was performed to validate SPAG5 as a prognostic candidate gene. Results: Mean SPAG5 expression value was significantly higher with some clinicopathological factors that resulted in tumor promotion and progression, including poor differentiated type, HER2 positive or TP53 mutated breast cancer. Based on ROC-analysis SPAG 5 is a suitable prognostic marker of poor survival. In patients who received chemotherapy alone, SPAG5 had only a moderate and not significant predictive impact on survival outcomes. However, in hormonal therapy, high SPAG5 expression could strongly predict prognosis with detrimental RFS (HR = 1.57, 95% CI 1.2-2.06, p = 0.001), OS (HR = 2, 95% CI 1.05-3.8, p = 0.03) and DMFS (HR = 2.36, 95% CI 1.57-3.54, p < 0.001), respectively. In addition, SPAG5 could only serve as a survival predictor in ER+, but not ER- breast cancer patients. Patients might also be at an increased risk of relapse despite being diagnosed with a lower grade cancer (well differentiated type). Conclusions: SPAG5 could be used as an independent prognostic and predictive biomarker that might have clinical utility, especially in ER+ breast cancer patients who received hormonal therapy. © 2019 The Author(s)

An Ecological Perspective On Song Learning In The Zebra Finch (Taeniopygia Guttata): The Role Of Social Influences

Communication is a social act, therefore learning to communicate cannot develop in a social vacuum. This thesis investigates vocal development in a songbird species, the Zebra finch, from an ecological perspective to understand the principles by which the naturalistic environment facilitates song learning. I focus my thesis on two such principles: the ways in which song learning is dependent on social affordances of the naturalistic social environment, and the ways in which structural regularities within the communication signal can be exploited to facilitate vocal learning. In Chapter 2 of the dissertation, I investigate what and how juvenile songbirds learn when provided with opportunities to interact with family members. Chapter 3 reveals that based on the structural variability in their father's song, juvenile males learn to sing statistically coherent grammatical structures. This is the first description of a new parallel between birdsong and language. In Chapter 4, I explore the contribution of social feedback in a strictly controlled vocal environment, by using contingent song playback on juvenile vocalizations to mimic naturalistic interactions. Overall, this thesis provides evidence that there is great potential for social interactions to guide the song learning process in the zebra finch, and song acquisition can only fully understood when it is studied in the context of a communication system

Gyermekkori genetikai rendellenességek diagnosztikája újgenerációs szekvenálással

Az újgenerációs szekvenáláson (NGS) alapuló diagnosztika legnagyobb előnye, hogy nagyszámú gén párhuzamos szekvenálása révén a genetikai rendellenességek kiterjedt repertoárját képes egyetlen vizsgálattal lefedni. Az analízis viszonylag kisebb költsége és az adatmennyiség kezelhetőbb mennyisége folytán a célzott génpanelek használata, illetve a teljesexom-szekvenálás (WES) a leginkább elérhető NGS-alapú módszer. Összefoglalónkban az NGS létjogosultságát vizsgáljuk gyermekkori genetikai rendellenességek diagnosztikájában. Áttekintjük az öröklött anyagcserezavarok, daganatos megbetegedések és egyéb gyermekkori genetikai rendellenességek NGS-alapú diagnosztikájában fontos szerepet játszó géneket. A kora gyermekkori rendellenességek NGS-alapú diagnosztikájának rutinszerű használata előtt számos technikai és klinikai kérdés vár még megválaszolásra. Jelenleg a legnagyobb kihívást a ritka genetikai variánsok értelmezése és a mutációk patogenitásának igazolása jelenti

A Comprehensive Outline of Trastuzumab Resistance Biomarkers in HER2 Overexpressing Breast Cancer

The introduction of trastuzumab for anti-HER2 therapy dramatically changed the clinical outcome for HER2 (ERBB2, neu) positive breast cancer patients. Today, patients eligible for trastuzumab are selected using HER2 expression/amplification status of the primary tumor. However, acquired and inherent resistance to anti-HER2 therapy in these patients poses a significant challenge, and better patient stratification will be needed to improve clinical response. Here, we provide a wide-ranging overview of potential biomarkers capable of stratifying patients regarding their response to trastuzumab. These include HER2 amplification, impaired access to the binding site (p95HER2, Delta16HER-2, MUC4), augmented signaling through other ERBB family receptors (HER1, HER3, HER4) and their ligands, activation of HER2 targets by alternate heterodimers (EphA2, IGF-1R, GDF15, MUC1*), signaling triggered by downstream members (PIK3CA, PTEN, SRC, mTOR), altered expression of cell cycle and apoptotic regulators (CDKs, p27(kip1), Bcl-2), hormone receptor status, resistance to antibody-dependent cellular cytotoxicity (FcgammaR), and altered miRNA expression signatures. Multigenic molecular profile analyses have revealed further genes not directly associated with classical oncogenic pathways. Although numerous biomarkers have shown promise in pre-clinical studies, many have delivered controversial results when evaluated in clinical trials. One of the keys for targeting ERBB2 will be to consider the entire ERBB family and downstream associated pathways responsible for the malignant transformation. The heterogeneity of the disease is likely to represent a significant obstacle to accurately predicting the course of resistance. The future most probably involves the incorporation of multiple biomarkers into a unified predictor enabling selection of patients for superior targeted drug administration

HOXC10 expression supports the development of chemotherapy resistance by fine tuning DNA repair in breast cancer cells

Development of drug resistance is a major factor limiting the continued success of cancer chemotherapy. To overcome drug resistance, understanding the underlying mechanism(s) is essential. We found that HOXC10 is overexpressed in primary carcinomas of the breast, and even more significantly in distant metastasis arising after failed chemotherapy. High HOXC10 expression correlates with shorter recurrence-free and overall survival in patients with estrogen receptor-negative breast cancer undergoing chemotherapy. We found that HOXC10 promotes survival in cells treated with doxorubicin, paclitaxel, or carboplatin by suppressing apoptosis and upregulating NF-κB. Overexpressed HOXC10 increases S-phase-specific DNA damage repair by homologous recombination (HR) and checkpoint recovery in cells at three important phases. For double-strand break repair, HOXC10 recruits HR proteins at sites of DNA damage. It enhances resection and lastly, it resolves stalled replication forks, leading to initiation of DNA replication following DNA damage. We show that HOXC10 facilitates, but is not directly involved in DNA damage repair mediated by HR. HOXC10 achieves integration of these functions by binding to, and activating cyclin-dependent kinase, CDK7, which regulates transcription by phosphorylating the carboxy-terminal domain of RNA polymerase II. Consistent with these findings, inhibitors of CDK7 reverse HOXC10-mediated drug resistance in cultured cells. Blocking HOXC10 function, therefore, presents a promising new strategy to overcome chemotherapy resistance in breast cancer. ©2016 AACR