Jan Stratmann

BACKGROUND: Angiotensin II (ATII), a potent vasoconstrictor, causes hypertension, promotes infiltration of myelomonocytic cells into the vessel wall, and stimulates both vascular and inflammatory cell NADPH oxidases. The predominant source of reactive oxygen species, eg, vascular (endothelial, smooth muscle, adventitial) versus phagocytic NADPH oxidase, and the role of myelomonocytic cells in mediating arterial hypertension have not been defined yet. METHODS AND RESULTS: Angiotensin II (1 mg · kg(-1) · d(-1) for 7 days) increased the number of both CD11b(+)Gr-1(low)F4/80(+) macrophages and CD11b(+)Gr-1(high)F4/80(-) neutrophils in mouse aorta (verified by flow cytometry). Selective ablation of lysozyme M-positive (LysM(+)) myelomonocytic cells by low-dose diphtheria toxin in mice with inducible expression of the diphtheria toxin receptor (LysM(iDTR) mice) reduced the number of monocytes in the circulation and limited ATII-induced infiltration of these cells into the vascular wall, whereas the number of neutrophils was not reduced. Depletion of LysM(+) cells attenuated ATII-induced blood pressure increase (measured by radiotelemetry) and vascular endothelial and smooth muscle dysfunction (assessed by aortic ring relaxation studies) and reduced vascular superoxide formation (measured by chemiluminescence, cytochrome c assay, and oxidative fluorescence microtopography) and the expression of NADPH oxidase subunits gp91(phox) and p67(phox) (assessed by Western blot and mRNA reverse-transcription polymerase chain reaction). Adoptive transfer of wild-type CD11b(+)Gr-1(+) monocytes into depleted LysM(iDTR) mice reestablished ATII-induced vascular dysfunction, oxidative stress, and arterial hypertension, whereas transfer of CD11b(+)Gr-1(+) neutrophils or monocytes from gp91(phox) or ATII receptor type 1 knockout mice did not. CONCLUSIONS- Infiltrating monocytes with a proinflammatory phenotype and macrophages rather than neutrophils appear to be essential for ATII-induced vascular dysfunction and arterial hypertension.

. Here we determined tumour phylogenies at diagnosis and throughout chemotherapy and immunotherapy by multiregion sequencing of 160 tumours from 65 patients. Treatment-naive SCLC exhibited clonal homogeneity at distinct tumour sites, whereas first-line platinum-based chemotherapy led to a burst in genomic intratumour heterogeneity and spatial clonal diversity. We observed branched evolution and a shift to ancestral clones underlying tumour relapse. Effective radio- or immunotherapy induced a re-expansion of founder clones with acquired genomic damage from first-line chemotherapy. Whereas TP53 and RB1 alterations were exclusively part of the common ancestor, MYC family amplifications were frequently not constituents of the founder clone. At relapse, emerging subclonal mutations affected key genes associated with SCLC biology, and tumours harbouring clonal CREBBP/EP300 alterations underwent genome duplications. Gene-damaging TP53 alterations and co-alterations of TP53 missense mutations with TP73, CREBBP/EP300 or FMN2 were significantly associated with shorter disease relapse following chemotherapy. In summary, we uncover key processes of the genomic evolution of SCLC under therapy, identify the common ancestor as the source of clonal diversity at relapse and show central genomic patterns associated with sensitivity and resistance to chemotherapy.

BACKGROUND: Atypical EGFR mutations occur in 10%-30% of non-small-cell lung cancer (NSCLC) patients with EGFR mutations and their sensitivity to classical epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) is highly heterogeneous. Patients harboring one group of uncommon, recurrent EGFR mutations (G719X, S768I, L861Q) respond to EGFR-TKI. Exon 20 insertions are mostly insensitive to EGFR-TKI but display sensitivity to exon 20 inhibitors. Clinical outcome data of patients with very rare point and compound mutations upon systemic treatments are still sparse to date. PATIENTS AND METHODS: In this retrospective, multicenter study of the national Network Genomic Medicine (nNGM) in Germany, 856 NSCLC cases with atypical EGFR mutations including co-occurring mutations were reported from 12 centers. Clinical follow-up data after treatment with different EGFR-TKIs, chemotherapy and immune checkpoint inhibitors were available from 260 patients. Response to treatment was analyzed in three major groups: (i) uncommon mutations (G719X, S7681, L861Q and combinations), (ii) exon 20 insertions and (iii) very rare EGFR mutations (very rare single point mutations, compound mutations, exon 18 deletions, exon 19 insertions). RESULTS: Our study comprises the largest thus far reported real-world cohort of very rare EGFR single point and compound mutations treated with different systemic treatments. We validated higher efficacy of EGFR-TKI in comparison to chemotherapy in group 1 (uncommon), while most exon 20 insertions (group 2) were not EGFR-TKI responsive. In addition, we found TKI sensitivity of very rare point mutations (group 3) and of complex EGFR mutations containing exon 19 deletions or L858R mutations independent of the combination partner. Notably, treatment responses in group 3 (very rare) were highly heterogeneous. Co-occurring TP53 mutations exerted a non-significant trend for a detrimental effect on outcome in EGFR-TKI-treated patients in groups 2 and 3 but not in group 1. CONCLUSIONS: Based on our findings, we propose a novel nNGM classification of atypical EGFR mutations.