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An isothermal, enzyme-free and sensitive electrochemical DNA sensor was developed for the detection of the FLT3 gene in acute myeloid leukemia (AML). First, aminated multi-walled carbon nanotubes (AMWNTs) and gold nanoparticles (AuNPs) were alternately self-assembled on a gold electrode using a layer-by-layer strategy. Then, the hairpin DNA probe 1 (H1), with a thiol group at the 3′ end and a ferrocenyl moiety (Fc) at the 5′ end, was immobilized on the AMWNTs/AuNPs multilayer films through Au–S bonding. When the target DNA (TD) appeared, it hybridized with and opened the hairpin structure of H1, and Fc was forced away from the electrode surface, leading to a significant decrease in the current peak of square wave voltammetry. Subsequently, the hairpin DNA probe 2 (H2) bound to H1, freeing the TD to trigger another reaction cycle. The combination of this target-catalyzed hairpin assembly and the LBL assembly of nanomaterials achieved a detection limit of 0.1 pM with a wide linear range of 0.1–1000 pM. The sensor discriminated between mismatched DNA and the target DNA with high selectivity. This dual signal amplification strategy is relatively simple and inexpensive because it does not need any enzymes or sophisticated equipment and successfully assayed the FLT3 gene from real samples. [ABSTRACT FROM AUTHOR]

Background New predictive biomarkers for cetuximab-resistance for patients with RAS wild-type colorectal liver metastases (CRLM). Methods 216 patients with initially unresectable liver-limited RAS wild-type CRLM were identified from previous clinical studies. Among these patients, 103 patients received chemotherapy (mFOLFOX6 or FOLFIRI) plus cetuximab, and 113 received chemotherapy alone as first-line treatment. Next-generation sequencing of primary tumors was done for single nucleotide polymorphism according to custom panel. The patients receiving cetuximab-based chemotherapy were divided into two groups: one group was cetuximab-resistant group and the other group was cetuximab-sensitive group. Potential predictive biomarkers were determined by "random forest" machine learning. Results Ten potential predictive genes, namely RET, PTPN11, FLT3, AKT1, ACTN4, ERBB4, FGFR3, MDC1, CUL9, and ZNF462, were identified. In the cohort of cetuximab-based chemotherapy, patients with all-wild-type genes had markedly improved median progression-free survival (12.0 vs. 4.0 months, P < 0.0001) and overall survival (37.0 VS. 24.0 months, P < 0.0001) compared with those with gene mutation; In the cohort of at-least-one gene mutation, patients receiving chemotherapy alone had comparable median PFS (4.0 VS. 4.0 months, P = 0.9498). Moreover, mutated are more common in patients with right-sided colon cancer. Conclusions Ten new predictive mutations help to refine the selection of RAS and BRAF wild-type metastatic colorectal cancer patients candidates for anti-EGFRs. Legal entity responsible for the study Zhongshan Hospital. Funding The National Natural Science Foundation of China. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

Background Early prediction of tumor response to therapy is essential for individualized treatment and sparing non-responders needless harm. A relationship has recently been found between pathologic response in breast cancer (BC) and a measure of cell loss based on serum levels of thymidine kinase 1 (sTK1), a macromolecule released when proliferating tumor cells are disrupted, and tumor volume. Objective: To establish whether the predictive power of this cell-loss metric can be further improved by baseline tumor characteristics. Methods Fifty-eight women with localized BC received neoadjuvant epirubicin/docetaxel in 6 cycles, supplemented with bevacizumab in cycle 3-6. The cell-loss metric, defined as the ratio between sTK1 (ng/ml) and tumor volume (cm3), was obtained prior to and 48h after cycle 2. The predictive value of this metric, and the improvement by adding routine baseline markers, was evaluated using pathologic response as endpoint (16 complete responses (pCR); 42 remaining tumors). Results Compared to baseline (median = 0.285 ng / ml), sTk1 increased 2-fold before cycle 2 and 3-fold 48h after cycle 2 while tumor volume (baseline 105 cm3) decreased by 70%. The cell loss method increased from 0.0032 units (IQR 0.0015-0.0099) to 0.0166 (0.0064-0.0423) and 0.0232 (0.0095-0.053), respectively, showing a strong association with pathological response (p = 0.002). Combination with histological markers, and especially the progesterone receptor, significantly improved the prediction of pCR, achieving positive and negative predictive values of 81% and 93%. Conclusions The usefulness of tumor markers in blood can be increased by combining them with other tumor properties. Thus, in neoadjuvant treatment of BC the cell-loss metric, which relates sTK1 to tumor volume, has been noticed as a predictor of pathologic response. Here we found that adding certain established tumor markers significantly improved the predictive power of the metric. Early prediction of tumor response makes the cell-loss metric potentially useful in personalized oncology and in the evaluation in new therapeutic modalities. Clinical trial identification PROMIX: NCT00957125. Legal entity responsible for the study Thomas Hatschek, MD, PhD, Karolinska University Hospital. Funding Has not received any funding. Disclosure B. Tribukait: Shareholder / Stockholder / Stock options, minor stock owner: AroCell Ab. [ABSTRACT FROM AUTHOR]

Background Genomic alterations of receptor tyrosine kinases (RTK) or ligands are biomarkers for some targeted therapies in a fraction of cancers, with heterogeneous responses across tumor types. A general model to predict the efficacy of a targeted treatment in a given tumor type bearing a RTK genomic alteration is lacking. Through database and literature review, we investigated whether the role of a RTK in the normal lineage could predict the response to RTK inhibitors in cancers arising from the same lineage. Methods An analysis of the literature and query of public databases on RTK function in normal cell lineages and neoplastic cells was conducted, for 16 selected RTK (EGFR, HER2, KIT, FLT3, TRKA-B-C, ROS1, ALK, RET, MET, and FGFR1-2-3-4). The physiological role of RTK in the development/maintenance of cell lineages was assessed by looking at the phenotypes resulting from the alteration of the RTK in animal models and/or known human germline mutations. The activity of TKI monotherapy in genomic-driven clinical trials was analyzed through a systematic review of published phase I-II-III studies. Efficacy was defined as a median progression-free survival > 6 months and of a response rate > 30%. A matrix was built to test the association between the physiological role and clinical activity of each RTK according to lineage contexts. Results This analysis reveals a relationship between the role in lineage development and the magnitude of clinical activity of a TKI in a cancer arising from the same lineage. For missense mutations only, the clinical activity was higher when the RTK is involved in the development or maintenance of the normal cell lineage. Conversely, in cancers harboring fusion genes and proteins involving an RTK, TKI were active regardless of cell lineage. Single agent TKI activity was consistently limited in cancers bearing RTK gene amplifications. Conclusions This analysis identifies two preferred genomic biomarkers to select candidate patient for single agent TKI, 1) fusions genes involving an RTK; 2) activating missense mutations in RTK involved in normal cell lineage physiology. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure P.A. Cassier: Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: Novartis; Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche/Genentech; Honoraria (self), Research grant / Funding (institution): Blueprint; Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: Amgen; Research grant / Funding (institution): Lilly; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): Celgene; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution), Travel / Accommodation / Expenses: Bristol-Myers Squibb; Research grant / Funding (institution), Travel / Accommodation / Expenses: Merck Sharp & Dohme; Research grant / Funding (institution): Tayo; Research grant / Funding (institution): Loxo; Research grant / Funding (institution): GlaxoSmithKline; Research grant / Funding (institution): Innate. I.L. Ray-Coquard: Honoraria (self), Research grant / Funding (self): Roche; Honoraria (self), Research grant / Funding (institution): Amgen; Honoraria (self), Research grant / Funding (institution): Genmab; Honoraria (self), Research grant / Funding (institution): AstraZeneca; Honoraria (self), Research grant / Funding (institution): Novartis; Honoraria (self), Research grant / Funding (institution): Pfizer. D. Pérol: Honoraria (self): AstraZeneca; Honoraria (self): Ipsen; Honoraria (self): Novartis; Honoraria (self): Lilly; Honoraria (self): Bristol-Myers Squibb. J-Y. Blay: Research grant / Funding (self): PharmaMar; Research grant / Funding (self): GlaxoSmithKline; Research grant / Funding (self): Novartis; Research grant / Funding (self): Eisai; Research grant / Funding (self): Lilly; Research grant / Funding (self): Merck Sharp and Dohme; Research grant / Funding (self): Bristol-Myers Squibb. All other authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

Background The five-year-survival-rate for paediatric patients with Acute Myeloid Leukaemia (AML) is from 60-70%. The most common causes of death are disease relapse and chemo-resistance. Typically, drug dose response testing is performed at atmospheric oxygen (21%) in a 2-Dimensional (2-D) format; however, AML cells reside in the hypoxic (1% O2), 3-Dimensional (3-D) bone marrow structure along with other cells. Therefore, the drug response observed in typical culture conditions (2D, 21% O2) do not always translate to the same response in patients. The objectives of the present study were to: (1) develop an in vitro assay reproducing key elements of the bone marrow microenvironment (BMM), and to (2) use this system to evaluate the sensitivity/resistance of AML cell lines towards selected therapeutic agents. Methods A functional drug screen was performed first in 2D normoxia and hypoxia to evaluate the response of AML cell lines to 50 compounds. RNA sequencing was performed to determine global changes of gene expression. Overrepresented genes were further matched to potential pathways using Ingenuity Pathway Analysis. Results were validated using real-time RT-PCR. MV-4-11, an AML cell line with a FLT3 mutation was used to study the effects of 3-D structure on drug response. Cells were seeded in 3D and allowed to grow for 72h, compounds were added for an additional 24 h and cell viability was measured using Cell Titer Glo assay. Results Twelve cell lines were used in the present study. In the initial screen THP1 cells for example were more sensitive in hypoxia to 8 out of 50 different compounds. In MV-4-11 cells, hypoxia and 3-D structure conferred resistance towards YM155, a BIRC5 targeting compound. Mechanistic studies revealed that MCL-1 stabilization may underlie this response. A functional drug screen using 50 compounds in 3-D showed that 10 out of 50 compounds resulted in significantly reduced viability of MV-4-11 cells compared to vehicle indicating that this assay can be used for high-throughput drug screening (HTS). Conclusions Hypoxia and 3D structure alter drug response in AML cells. The proposed 3D assay can be used for HTS. Clinical application of this study may lead to more accurate predictions of therapeutic outcomes. Legal entity responsible for the study The authors. Funding Children Cancer Network. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

Background FLT3-ITD mutations occur in about 25% of patients (pts) with acute myeloid leukemia (AML) and are associated with poor outcomes. Pts with relapsed/refractory (R/R) FLT3-ITD AML have worse prognosis and high unmet medical need. Quizartinib (Q) is a potent and selective FLT3i with promising activity and a manageable safety profile. QuANTUM-R was a global, phase 3, randomized trial of Q vs chemotherapy (SC) in pts with R/R FLT3-ITD AML (NCT02039726). Methods Pts with R/R FLT3-ITD AML w/wo hematopoietic stem cell transplant (HSCT) were randomized to receive Q or a preselected investigator choice SC: low-dose cytarabine; mitoxantrone, etoposide, and intermediate-dose cytarabine (MEC); or fludarabine, cytarabine, and G-CSF with idarubicin (FLAG-IDA). Prior midostaurin was allowed. Pts receiving HSCT after Q could resume Q after HSCT. Primary and secondary endpoints were overall survival (OS) and event-free survival (EFS), respectively. Exploratory endpoints included response rate, time to and duration of response, and transplant rate. Results 367 pts were randomized; 245 to Q and 122 to SC. Median follow-up was 23.5 mo. OS hazard ratio (HR) of Q relative to SC was 0.76 (95% CI, 0.58-0.98; P=.0177). Median OS was 6.2 (95% CI, 5.3-7.2) vs 4.7 (95% CI, 4.0-5.5) mo in Q and SC arms, respectively. EFS HR was 0.90 (95% CI, 0.70-1.16; P=.1071); median EFS was 1.4 (95% CI, 0.0-1.9) vs 0.9 (95% CI, 0.4-1.3) mo, respectively. Sensitivity analyses and OS subgroup analyses supported Q vs SC. Composite complete response (CRc) was 48% and 27% in Q and SC arms, respectively. Transplant rate was 32% (Q) and 12% (SC). Median time to first CRc was 4.9 wk for Q. The most common grade ≥ 3 TEAEs in both arms were infections and those associated with cytopenia. Conclusion OS benefit was observed with single-agent Q vs SC in pts with R/R FLT3-ITD AML with a favorable Q safety profile, providing evidence of meaningful clinical benefit in pts with limited treatment options. [ABSTRACT FROM AUTHOR]