PIK3CA E542K

Characterization of the two different approaches in terms of sensitivity results in comparable detection limits (229 copies μL-1 and 224 copies μL-1, respectively), though RPA followed by lambda exonuclease digestion yields significantly higher currents. Finally, this method, together with a designed wild-type blocking oligo that inhibits binding of the wild-type target DNA during probe-target hybridization, allows for detecting the PIK3CA point mutations H1047R, E545K, and E542K in the presence of wild-type target DNA when the proportion of mutant target DNA is >20%.

Background The AKT inhibitor capivasertib was recently approved in the 2L+ setting for patients (pts) with hormone receptor-positive metastatic breast cancer with alterations in PIK3CA, AKT1, and/or PTEN...However, one-third of patients have variants beyond E542, E545, and H1047 with less certainty about targetability. The preponderance of rare PIK3CA mutations and co-occurrences between PIK3CA, AKT1, and PTEN with genes outside the PI3K pathway merits functional investigation.

However, clinical trials have been predominantly carried out with selected populations and single drugs (Palbociclib, Ribociclib or Abemaciclib). At baseline, and considering the pre-defined criteria, ctDNA analysis detected PIK3CA mutations in 32.25% and 44.44% of patients by AVENIO and ddPCR, respectively. ESR1 mutations were detected in 3.22% and 9.37% by AVENIO and ddPCR, respectively. For PIK3CA mutations, the Kappa value was 0.62 (p-value: 0.0004) and 0.47 for ESR1 mutations (p-value: 0.0039).

Multi-hit mutations in PIK3CA are seen in 1.7% of advanced CRC, a meaningful prevalence given the high burden of CRC worldwide, and may represent a subset of patients that have enhanced sensitivity to PI3K inhibition. Future investigation regarding the clinical utility of PI3K inhibitors is warranted in multi-hit PIK3CA CRC.

The developed novel multi-marker liquid bead array assay for the simultaneous detection of PIK3CA and ESR1 hotspot mutations in single CTCs is highly specific, highly sensitive, high-throughput, and sample-, cost-, and time-saving. This multi-marker liquid bead array assay can be extended to detect up to 100 mutations in many genes at once and can be applied for bulk CTC and ctDNA analysis.

However, the role of mutated PIK3CA in adenocarcinoma has not been discussed. In addition, mutations occurring in other main members of the PI3K-AKT-mTOR signaling pathway other than PIK3CA were also excluded.

PIK3CD/PIK3R1 (p110 δ/p85 α) is the most, with 65% inhibition, suggesting a possible mechanism of anticancer properties. Furthermore, the NCI 60-cell line inhibition demonstrates promising broad anticancer inhibition against numerous cancer cell lines of OMS5 and OMS14, which could be good lead compounds for future development.

The commercially available Oncolipsy PIK3CA CE-IVD kit is highly sensitive and specific for the detection of four PIK3CA hotspot mutations in primary tumors and plasma-cfDNA.

Bone sarcomas associated with infarcts exhibit genomic instability, with pronounced copy number variations, especially in Chromosome 12. CDKN2A/B homozygous deletion is highly prevalent, whereas TP53 alterations appear less frequent than in osteosarcomas. MDM2 amplification and H3.3-G34 mutations are recurrent (33%).

The results of this study show that this strategy has significant advantages such as high selectivity, a simple process, no special instruments and equipment, no need for fluorescence modification of hairpin probes in advance, high automation, low cost, and minimal sample consumption. This provides a powerful method for the detection of trace cancer biomarkers in the serum matrix with good application prospects.

This research provides a label-free and minute-scale universal method for the detection of various malignant tumors. The ctDNA biosensors based on the ACEK effect improved according to the probe type or electrode structure and have potential applications in tumor drug efficacy prediction, drug resistance monitoring, screening of high-risk groups, differential diagnosis, monitoring of tiny residual lesions, and prognosis determination.

PIK3CA-E542K, ErbB2 amplification, and SMAD4 mutations could be potential biomarkers for PD-1 inhibitors, but a single instance is insufficient to validate the hypotheses. A larger number of patients or more clinical data will be necessary to determine whether these gene mutations are appropriate biomarkers for patients when treatment with PD-1 inhibitors.