Sotorasib for Vascular Malformations Associated with KRAS G12C Mutation.

KRAS gain-of-function mutations are frequently observed in sporadic arteriovenous malformations. The mechanisms underlying the progression of such KRAS-driven malformations are still incompletely understood, and no treatments for the condition are approved. Here, we show the effectiveness of sotorasib, a specific KRAS G12C inhibitor, in reducing the volume of vascular malformations and improving survival in two mouse models carrying a mosaic Kras G12C mutation. We then administered sotorasib to two adult patients with severe KRAS G12C-related arteriovenous malformations. Both patients had rapid reductions in symptoms and arteriovenous malformation size. Targeting KRAS G12C appears to be a promising therapeutic approach for patients with KRAS G12C-related vascular malformations. (Funded by the European Research Council and others.).

Microchip for Immunomagnetic Sorting of Circulating Tumor Cells (CTCs).

Circulating tumor cells (CTCs) isolated directly from whole blood opens new perspectives for cancer monitoring and the development of personalized treatments. However, due to their rarity among the multitude of blood cells, it remains a challenge to recover them alive with high level of purity, i.e., with few remaining white blood cells, and in a time frame compatible with the clinical context. Microfluidic chips have emerged as promising tools to address these challenges. We propose a two-step workflow including a pre-enrichment step, performed by a size-based pre-enrichment system, and a purification step, performed by an immunomagnetic chip. Here, we describe the protocol for the fabrication of the immunomagnetic microchip, the preparation of the sample, and the procedure for injection into the microchip allowing the sorting of the CTCs.

Neuropilin 2 and soluble neuropilin 2 in neuroendocrine neoplasms.

Neuropilin 2 (NRP2), a transmembrane non-tyrosine kinase receptor, has been described as a potential critical player in the tumourigenesis of several solid cancers and particularly in neuroendocrine neoplasms (NENs). A soluble form of NRP2 (sNRP2) has been previously described and corresponds to a truncated splice isoform. Its prognostic value has never been studied in NEN. NRP2 expression was studied by immunochemistry on tissue microarrays (n = 437) and on circulating tumour cells (CTCs, n = 5 patients with neuroendocrine carcinoma, NEC). We described the levels of sNRP2 in 229 patients with NEN using the ELISA method to identify the factors associated with sNRP2 levels and to evaluate its prognostic role; 90 blood donors represented the healthy control group. NRP2 was found in 97% of neuroendocrine tumours (396/410) and in 74% of NEC (20/27). NRP2 was also expressed in CTC of all the studied patients. The receiver operating characteristic (ROC) analysis showed that sNRP2 had a weak capacity to discriminate between NEN patients and healthy controls (area under curve (AUC) = 0.601, P = 0.053). Abnormal sNRP2 levels were associated with inflammatory syndrome, bone and peritoneal metastases, and abnormal chromogranin A levels. Patients with high sNRP2 levels (sNRP2Q3-Q4) had significantly poorer overall survival in multivariate analysis (HR 0.16, 95% CI (0.04-0.67), P = 0.015). In conclusion, the present study found that sNRP2 and NRP2 could represent a new prognostic biomarker and a therapeutic target, respectively, particularly in aggressive NEN.

Intraperitoneal Nivolumab after Debulking Surgery and Hyperthermic Intraperitoneal Chemotherapy in Advanced Ovarian Cancer: A Phase I Study with Expansion Cohort.

PURPOSE: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are expected to be synergistic with intraperitoneal (IP) immunotherapy by increasing tumor antigen expression and mutational load. We assessed the feasibility and safety of IP nivolumab following complete CRS and HIPEC in pretreated patients with recurrent ovarian cancer (ClinicalTrials.gov identifier: NCT03959761). PATIENTS AND METHODS: Patients received IP nivolumab (0.5, 1, or 3 mg/kg) using a 3 + 3 dose-escalation design, starting 5 to 7 days after CRS and HIPEC. Four IP Q2W (once every 2 weeks) nivolumab infusions were planned. The primary objective was to demonstrate the feasibility of IP nivolumab based on dose-limiting toxicity. Secondary objectives were to assess changes in tolerance of CRS and HIPEC. RESULTS: A total of 17 patients were enrolled including 10 patients in the dose escalation and 7 patients in the expansion phase. No dose-limiting toxicity was observed at any dose level in the 9 evaluable patients. Six of the 17 patients (35%) did not complete all planned infusions: 4 (23.5%) due to peritoneal catheter complications and 2 (11.8%) due to early progression. No procedure-related deaths occurred. Eleven patients (65%) experienced serious adverse events (SAE), mainly transitory grade 3 to 4 transaminase elevations (6/11) and surgery-related (9/11). Four SAEs were related to the peritoneal catheter and two to HIPEC. No SAEs/grade 3 to 4 adverse events related to IP nivolumab occurred. CONCLUSIONS: This is the first study demonstrating the feasibility of IP nivolumab in patients with relapsed advanced ovarian cancer. Further investigation at 3 mg/kg is warranted.

Direct Comparative Analysis of a Pharmacogenomics Panel with PacBio Hifi® Long-Read and Illumina Short-Read Sequencing.

BACKGROUND: Pharmacogenetics (PGx) aims to determine genetic signatures that can be used in clinical settings to individualize treatment for each patient, including anti-cancer drugs, anti-psychotics, and painkillers. Taken together, a better understanding of the impacts of genetic variants on the corresponding protein function or expression permits the prediction of the pharmacological response: responders, non-responders, and those with adverse drug reactions (ADRs). OBJECTIVE: This work provides a comparison between innovative long-read sequencing (LRS) and short-read sequencing (SRS) techniques. METHODS AND MATERIALS: The gene panel captured using PacBio HiFi® sequencing was tested on thirteen clinical samples on GENTYANE's platform. SRS, using a comprehensive pharmacogenetics panel, was performed in routine settings at the Civil Hospitals of Lyon. We focused on complex regions analysis, including copy number variations (CNVs), structural variants, repeated regions, and phasing-haplotyping for three key pharmacogenes: CYP2D6, UGT1A1, and NAT2. RESULTS: Variants and the corresponding expected star (*) alleles were reported. Although only 38.4% concordance was found for haplotype determination and 61.5% for diplotype, this did not affect the metabolism scoring. A better accuracy of LRS was obtained for the detection of the CYP2D6*5 haplotype in the presence of the duplicated wild-type CYP2D6*2 form. A total concordance was performed for UGT1A1 TA repeat detection. Direct phasing using the LRS approach allowed us to correct certain NAT2 profiles. CONCLUSIONS: Combining an optimized variant-calling pipeline and with direct phasing analysis, LRS is a robust technique for PGx analysis that can minimize the risk of mis-haplotyping.