The benefit and risk of PD-1/PD-L1 inhibitors plus anti-angiogenic agents as second or later-line treatment for patients with advanced non-small-cell lung cancer: a systematic review and single-arm meta-analysis of prospective clinical trials.

Background: Previous studies revealed that Programmed cell death protein 1 (PD-1)/Programmed cell death-Ligand protein 1 (PD-L1) inhibitors plus anti-angiogenic agents had extensive anti-tumor activities. However, almost all studies on the efficacy and safety of PD-1/PD-L1 inhibitors plus anti-angiogenic agents as second or later-line treatment for patients with advanced non-small cell lung cancer are non-randomized controlled trials with small sample sizes, which might lead to a lack of effective metrics to assess the effectiveness and safety of the therapeutic regimen. Here, this meta-analysis aimed to evaluate the efficacy and safety of PD-1/PD-L1 inhibitors plus anti-angiogenic agents as second or later-line treatment for patients with advanced non-small cell lung cancer. Methods: A single-arm meta-analysis was performed, and published literature from PubMed, Web of Science and Embase databases as of January 13, 2023, was systematically retrieved. We used the Cochrane risk of bias tool and methodological index for non-randomized studies (MINORS) Methodological items to evaluate the quality of eligible clinical trials. Outcomes including overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs) were extracted for further analysis. The random effect model is used to calculate the pooled parameters. Results: 19 studies (16 were non-comparative single-arm clinical trials and 3 were randomized controlled trials) were enrolled in this meta-analysis. In terms of tumor response, the pooled ORR and DCR were 22.4% (95% CI, 16.6-28.1%) and 76.8% (95% CI, 72.6-81.1%), respectively. With regard to survival analysis, the pooled PFS and OS were 5.20 (95% CI, 4.46-5.93) months and 14.09 (95% CI, 13.20-14.97) months, respectively. The pooled grade ≥3 adverse effect (AE) rate was 47.6% (95% CI, 33.1-62.0%). Conclusion: PD-1/PD-L1 inhibitors plus anti-angiogenic agents has promising efficacy and safety as second or later-line treatment in patients with advanced non-small cell lung cancer. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023407559.

HetI-Like Phosphopantetheinyl Transferase Posttranslationally Modifies Acyl Carrier Proteins in Xanthomonas spp.

In Xanthomonas spp., the biosynthesis of the yellow pigment xanthomonadin and fatty acids originates in the type II polyketide synthase (PKS II) and fatty acid synthase (FAS) pathways, respectively. The acyl carrier protein (ACP) is the central component of PKS II and FAS and requires posttranslational phosphopantetheinylation to initiate these pathways. In this study, for the first time, we demonstrate that the posttranslational modification of ACPs in X. campestris pv. campestris is performed by an essential 4'-phosphopantetheinyl transferase (PPTase), XcHetI (encoded by Xc_4132). X. campestris pv. campestris strain XchetI could not be deleted from the X. campestris pv. campestris genome unless another PPTase-encoding gene such as Escherichia coli acpS or Pseudomonas aeruginosa pcpS was present. Compared with wild-type strain X. campestris pv. campestris 8004 and mutant XchetI::PapcpS, strain XchetI::EcacpS failed to generate xanthomonadin pigments and displayed reduced pathogenicity for the host plant, Brassica oleracea. Further experiments showed that the expression of XchetI restored the growth of E. coli acpS mutant HT253 and, when a plasmid bearing XchetI was introduced into P. aeruginosa, pcpS, which encodes the sole PPTase in P. aeruginosa, could be deleted. In in vitro enzymatic assays, XcHetI catalyzed the transformation of 4'-phosphopantetheine from coenzyme A to two X. campestris pv. campestris apo-acyl carrier proteins, XcAcpP and XcAcpC. All of these findings indicate that XcHetI is a surfactin PPTase-like PPTase with a broad substrate preference. Moreover, the HetI-like PPTase is ubiquitously conserved in Xanthomonas spp., making it a potential new drug target for the prevention of plant diseases caused by Xanthomonas.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.