DDB2 expression lights the way for precision radiotherapy response in PDAC cells, with or without olaparib.

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers. Therapeutic options for PDAC are primarily restricted to surgery in the early stages of the disease or chemotherapy in advanced disease. Only a subset of patients with germline defects in BRCA1/2 genes can potentially benefit from personalized therapy, with the PARP inhibitor olaparib serving as a maintenance treatment for metastatic disease.

Tumor-derived cell-free DNA and circulating tumor cells: partners or rivals in metastasis formation?

The origin of metastases is a topic that has sparked controversy. Despite recent advancements, metastatic disease continues to pose challenges. The first admitted model of how metastases develop revolves around cells breaking away from the primary tumor, known as circulating tumor cells (CTCs).

Integrated Molecular Characterization of HER2-Low Breast Cancer Using Next Generation Sequencing (NGS).

Based on immunohistochemistry (IHC) and in situ hybridization (ISH), HER2-low breast cancers (BC) subtype-defined as IHC1+ or IHC2+/ISH- tumors-emerged and represent more than half of all BC. We evaluated the performance of NGS for integrated molecular characterization of HER2-low BC, including identification of actionable molecular targets, copy number variation (CNV), and microsatellite instability (MSI) analysis. Thirty-one BC specimens (11 HER2+, 10 HER2-, and 10 HER2-low) were routinely analyzed using IHC and ISH, and were selected and analyzed using NGS for gene mutations including , , , , , , and , CNV, and MSI.

GIInger predicts homologous recombination deficiency and patient response to PARPi treatment from shallow genomic profiles.

Homologous recombination deficiency (HRD) is a predictive biomarker for poly(ADP-ribose) polymerase 1 inhibitor (PARPi) sensitivity. Routine HRD testing relies on identifying BRCA mutations, but additional HRD-positive patients can be identified by measuring genomic instability (GI), a consequence of HRD. However, the cost and complexity of available solutions hamper GI testing.

Gene Mutations and Liquid Biopsy in ER-Positive Breast Cancers: A Small Step Forward, a Giant Leap for Personalization of Endocrine Therapy?

The predominant forms of breast cancer (BC) are hormone receptor-positive (HR+) tumors characterized by the expression of estrogen receptors (ERs) and/or progesterone receptors (PRs). Patients with HR+ tumors can benefit from endocrine therapy (ET). Three types of ET are approved for the treatment of HR+ BCs and include selective ER modulators, aromatase inhibitors, and selective ER downregulators.

CRISPR/Cas9-mediated knock-in of BRCA1/2 mutations restores response to olaparib in pancreatic cancer cell lines.

Pancreatic cancer is one of the most aggressive diseases with a very poor outcome. Olaparib, a PARP inhibitor, as maintenance therapy showed benefits in patients with metastatic pancreatic adenocarcinoma bearing germline BRCA1/2 mutations. However, germline BRCA mutation has been described in only 4-7% of patients with pancreatic adenocarcinoma.

Validation of the Idylla GeneFusion assay to detect fusions and MET exon-skipping in non-small cell lung cancers.

Gene fusions and MET exon skipping drive oncogenesis in 8-9% and 3% of non-small cell lung cancers (NSCLC) respectively. Their detection are essential for the management of patients since they confer sensitivity to specific targeted therapies with significant clinical benefit over conventional chemotherapy. Immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) account for historical reference techniques however molecular-based technologies (RNA-based sequencing and RT-PCR) are emerging as alternative or complementary methods.

DDB2 represses epithelial-to-mesenchymal transition and sensitizes pancreatic ductal adenocarcinoma cells to chemotherapy.

Introduction: Damage specific DNA binding protein 2 (DDB2) is an UV-indiced DNA damage recognition factor and regulator of cancer development and progression. DDB2 has dual roles in several cancers, either as an oncogene or as a tumor suppressor gene, depending on cancer localization. Here, we investigated the unresolved role of DDB2 in pancreatic ductal adenocarcinoma (PDAC).

Deciphering Tumour Heterogeneity: From Tissue to Liquid Biopsy.

Human solid malignancies harbour a heterogeneous set of cells with distinct genotypes and phenotypes. This heterogeneity is installed at multiple levels. A biological diversity is commonly observed between tumours from different patients (inter-tumour heterogeneity) and cannot be fully captured by the current consensus molecular classifications for specific cancers.

Intraoperative prediction of non-sentinel lymph node metastases in breast cancer using cytokeratin 19 mRNA copy number: A retrospective analysis.

One-step nucleic acid amplification (OSNA) is a molecular procedure used intraoperatively for the detection of sentinel lymph node (SLN) metastases. The aim of the present study was to define a cut-off of cytokeratin (CK)19 mRNA copy number predictive of positive completion axillary lymph node dissection (ALND). The OSNA procedure was employed for SLN analysis in 812 patients with T1-T2 N0 breast cancer.

Epithelial to Mesenchymal Transition in Patients with Pancreatic Ductal Adenocarcinoma: State-of-the-Art and Therapeutic Opportunities.

Pancreatic ductal adenocarcinoma (PDAC) is one of the malignancies with the worst prognosis despite a decade of efforts. Up to eighty percent of patients are managed at late stages with metastatic disease, in part due to a lack of diagnosis. The effectiveness of PDAC therapies is challenged by the early and widespread metastasis.

Evaluation of the Idylla ctEGFR mutation assay to detect EGFR mutations in plasma from patients with non-small cell lung cancers.

The assessment of EGFR mutations is recommended for the management of patients with non-small cell lung cancer (NSCLC). Presence of EGFR mutation is associated with response or resistance to EGFR tyrosine kinase inhibitors (EGFR-TKI). Liquid biopsy is nowadays widely used for the detection of resistance to EGFR-TKI.

Detection of Microsatellite Instability: State of the Art and Future Applications in Circulating Tumour DNA (ctDNA).

Microsatellite instability (MSI) is a molecular scar resulting from a defective mismatch repair system (dMMR) and associated with various malignancies. MSI tumours are characterized by the accumulation of mutations throughout the genome and particularly clustered in highly repetitive microsatellite (MS) regions. MSI/dMMR status is routinely assessed in solid tumours for the initial screening of Lynch syndrome, the evaluation of cancer prognosis, and treatment decision-making.

Evaluation of 3 molecular-based assays for microsatellite instability detection in formalin-fixed tissues of patients with endometrial and colorectal cancers.

Microsatellite instability (MSI) status is routinely assessed in patients with colorectal and endometrial cancers as it contributes to Lynch syndrome initial screening, tumour prognosis and selecting patients for immunotherapy. Currently, standard reference methods recommended for MSI/dMMR (deficient MisMatch Repair) testing consist of immunohistochemistry and pentaplex PCR-based assays, however, novel molecular-based techniques are emerging. Here, we aimed to evaluate the performance of a custom capture-based NGS method and the Bio-Rad ddPCR and Idylla approaches for the determination of MSI status for theranostic purposes in 30 formalin-fixed paraffin embedded (FFPE) tissue samples from patients with endometrial (n = 15) and colorectal (n = 15) cancers.

SMAD4 and the TGFβ Pathway in Patients with Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer death worldwide. PDAC is an aggressive disease with an 11-month median overall survival and a five-year survival of less than 5%. Incidence of PDAC is constantly increasing and is predicted to become the second leading cause of cancer in Western countries within a decade.

Evaluation of KRAS, NRAS and BRAF mutations detection in plasma using an automated system for patients with metastatic colorectal cancer.

Background: Cell-free DNA detection is becoming a surrogate assay for tumor genotyping. Biological fluids often content a very low amount of cell-free tumor DNA and assays able to detect very low allele frequency mutant with a few quantities of DNA are required. We evaluated the ability of the fully-automated molecular diagnostics platform Idylla for the detection of KRAS, NRAS and BRAF hotspot mutations in plasma from patients with metastatic colorectal cancer (mCRC).

Rapid fully-automated assay for routine molecular diagnosis of mutations for personalized therapy of low grade gliomas.

mutation analysis is important to personalize the management with low-grade gliomas (LGG) in children and adults, with therapeutic and prognostic impacts. In recurrent tumors, targeted therapies such as BRAF inhibitors had been reported to induce disease stabilization and significant radiographic responses. This highlights the potential interest of mutation to stratify patients for targeted therapy.

Emerging Roles of DDB2 in Cancer.

Damage-specific DNA-binding protein 2 (DDB2) was originally identified as a DNA damage recognition factor that facilitates global genomic nucleotide excision repair (GG-NER) in human cells. DDB2 also contributes to other essential biological processes such as chromatin remodeling, gene transcription, cell cycle regulation, and protein decay. Recently, the potential of DDB2 in the development and progression of various cancers has been described.

Enrichment and Analysis of ctDNA.

ctDNA provided by liquid biopsy offers a promising alternative to tumor biopsy as it gives a non-invasive and «real-time» access to the cancer genome and reflects tumor intra and extra heterogeneity. ctDNA has shown growing clinical interest for cancer diagnosis, prognosis, theragnostics, therapeutic monitoring, and clonal evolution tracking. A major technical limit for ctDNA analysis from body fluids is the extremely low proportion of ctDNA compared to non-malignant cell-free DNA, underscoring the need for highly sensitive and specific detection techniques.

Evaluation of KRAS, NRAS and BRAF hotspot mutations detection for patients with metastatic colorectal cancer using direct DNA pipetting in a fully-automated platform and Next-Generation Sequencing for laboratory workflow optimisation.

Background: Assessment of KRAS, NRAS (RAS) and BRAF mutations is a standard in the management of patients with metastatic colorectal cancer (mCRC). Mutations could be assessed using next-generation sequencing (NGS) or real-time PCR-based assays. Times to results are 1 to 2 weeks for NGS and 1 to 3 days for real-time PCR-based assays.

Uncommon mutational profiles of metastatic colorectal cancer detected during routine genotyping using next generation sequencing.

RAS genotyping is mandatory to predict anti-EGFR monoclonal antibodies (mAbs) therapy resistance and BRAF genotyping is a relevant prognosis marker in patients with metastatic colorectal cancer. Although the role of hotspot mutations is well defined, the impact of uncommon mutations is still unknown. In this study, we aimed to discuss the potential utility of detecting uncommon RAS and BRAF mutation profiles with next-generation sequencing.

Integrated routine workflow using next-generation sequencing and a fully-automated platform for the detection of KRAS, NRAS and BRAF mutations in formalin-fixed paraffin embedded samples with poor DNA quality in patients with colorectal carcinoma.

Background: KRAS and NRAS mutations are identified resistance mutations to anti-epidermal growth factor receptor monoclonal antibodies in patients with metastatic colorectal cancer. BRAF status is also routinely assessed for its poor prognosis value. In our institute, next-generation sequencing (NGS) is routinely used for gene-panel mutations detection including KRAS, NRAS and BRAF, but DNA quality is sometimes not sufficient for sequencing.

Technical considerations for circulating tumor DNA detection in oncology.

Blood draw or collection of other body fluids, known as 'liquid biopsies' are generally less invasive procedures than tumor biopsies. Cell-free tumor DNA (ctDNA) is widely evaluated in cancer for early detection, diagnosis, prognosis, therapy monitoring or determination of minimal residual disease. In body fluid samples, ctDNA can represent a small fraction of total cell-free DNA (cfDNA), requiring highly sensitive assays.

The pyrrolopyrimidine colchicine-binding site agent PP-13 reduces the metastatic dissemination of invasive cancer cells in vitro and in vivo.

Standard chemotherapies that interfere with microtubule dynamics are a chemotherapeutic option used for the patients with advanced malignancies that invariably relapse after targeted therapies. However, major efforts are needed to reduce their toxicity, optimize their efficacy, and reduce cancer chemoresistance to these agents. We previously identified a pyrrolo[2,3d]pyrimidine-based microtubule-depolymerizing agent (PP-13) that binds to the colchicine site of β-tubulin and exhibits anticancer properties in solid human cancer cells, including chemoresistant subtypes.

Clinical Interest of Circulating Tumor DNA in Oncology.

Genetic alterations in tumors, as predictor of response to targeted-therapies or as prognostic markers, are clinically relevant to determine adequate therapeutic management. Tumor biopsy is currently the golden standard for somatic alterations assessment, but this approach is invasive and does not consider tumor heterogeneity. In various body fluids like plasma, somatic mutations have been identified.