A prognostic miRNA based signature in early-stage HER2-positive breast cancer patients.

e12600 Background: In early-stage HER2+ breast cancer (BC), escalation or de-escalation of systemic treatment is an unmet need. Integration of promising biomarkers into risk scoring will further help progressing in the field. We aim to develop a prognostic signature that integrates two miRNAs (A and B) and quantitative and qualitative clinical variables in patients diagnosed with HER2+ BC. Methods: This study was conducted in a retrospective cohort of 45 HER2+ BC patients. Patients received standard treatment for localized disease. We calculated a prognostic signature for disease-free survival (DFS) using principal components analysis for mixed data combining clinicopathological data (Ki67…

464P Exome sequencing of ctDNA portrays the mutational landscape of patients with relapsing colon cancer and indicates new actionable targets

Detection of postoperative plasma circulating tumour DNA and lack of CDX2 expression as markers of recurrence in patients with localised colon cancer

BACKGROUND: Colon cancer (CC) is a heterogeneous disease. Novel prognostic factors beyond pathological staging are required to accurately identify patients at higher risk of relapse. Integrating these new biological factors, such as plasma circulating tumour DNA (ctDNA), CDX2 staining, inflammation-associated cytokines and transcriptomic consensus molecular subtypes (CMS) classification, into a multimodal approach may improve our accuracy in determining risk of recurrence.; METHODS: One hundred and fifty patients consecutively diagnosed with localised CC were prospectively enrolled in our study. ctDNA was tracked to detect minimal residual disease by droplet digital PCR. CDX2 expression was…

Targeted next-generation sequencing of circulating-tumor DNA for tracking minimal residual disease in localized colon cancer.

A high percentage of patients diagnosed with localized colon cancer (CC) will relapse after curative treatment. Although pathological staging currently guides our treatment decisions, there are no biomarkers determining minimal residual disease (MRD) and patients are at risk of being undertreated or even overtreated with chemotherapy in this setting. Circulating-tumor DNA (ctDNA) can to be a useful tool to better detect risk of relapse.One hundred and fifty patients diagnosed with localized CC were prospectively enrolled in our study. Tumor tissue from those patients was sequenced by a custom-targeted next-generation sequencing (NGS) panel to characterize somatic mutations. A minimum varian…

1432P Characterizing diversity in the immune profile by a transcriptomic customized gene signature to potentially personalize treatment in advanced gastric cancer patients

Expanded CTG repeats trigger miRNA alterations in Drosophila that are conserved in myotonic dystrophy type 1 patients

Myotonic dystrophy type 1 (DM1) is caused by the expansion of CTG repeats in the 3' untranslated region of the DMPK gene. Several missplicing events and transcriptional alterations have been described in DM1 patients. A large number of these defects have been reproduced in animal models expressing CTG repeats alone. Recent studies have also reported miRNA dysregulation in DM1 patients. In this work, a Drosophila model was used to investigate miRNA transcriptome alterations in the muscle, specifically triggered by CTG expansions. Twenty miRNAs were differentially expressed in CTG-expressing flies. Of these, 19 were down-regulated, whereas 1 was up-regulated. This trend was confirmed for thos…

Clinical application of mutational analysis in breast cancer patients: The relevance of PIK3CA analysis for precision medicine

Abstract Background The identification of biomarkers to drive treatment is one of the most important objectives of precision medicine. During last years, the role of PIK3CA mutations have been related to clinical benefit deriving from treatment with PI3K, and mTOR inhibitors. In breast cancer (BC), PIK3CA mutations are widely present and the use, in clinical trials, of selective inhibitors improved clinical outcomes. The aim of this study is to assess the value of a monocentric genomic screening program to select patients for trials with experimental targeted agents. Methods We examined PIK3CA mutation in a cohort of 312 metastatic BC patients diagnosed at Hospital Clinico Valencia-INCLIVA …