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Triple-negative breast cancer (TNBC) could benefit from PARP inhibitors (PARPi) for their frequent defective homologous recombination repair (HR). However, the efficacy of PARPi is limited by their lower bioavailability and high susceptibility to drug resistance, so it often needs to be combined with other treatments. Herein, polydopamine nanoparticles (PDMN) were constructed to load Olaparib (AZD) as two-channel therapeutic nanoplatforms. The PDMN has a homogeneous spherical structure around 100 nm and exhibits a good photothermal conversion efficiency of 62.4%. The obtained AZD-loaded nanoplatform (PDMN-AZD) showed enhanced antitumor effects through the combination of photothermal therapy (PTT) and PARPi. By western blot and flow cytometry, we found that PTT and PARPi could exert synergistic antitumor effects by further increasing DNA double-strand damage (DSBs) and enhancing HR defects. The strongest therapeutic effect of PDMN-AZD was observed in a BRCA-deficient mouse tumor model. In conclusion, the PDMN-AZD nanoplatform designed in this study demonstrated the effectiveness of PTT and PARPi for synergistic treatment of TNBC and preliminarily explained the mechanism., (© 2024. Controlled Release Society.)

OsMADS1 plays a vital role in regulating floret development and grain shape, but whether it regulates rice grain quality still remains largely unknown. Therefore, we used comprehensive molecular genetics, plant biotechnology, and functional omics approaches, including phenotyping, mapping-by-sequencing, target gene seed-specific RNAi, transgenic experiments, and transcriptomic profiling to answer this biological and molecular question. Here, we report the characterization of the 'Oat-like rice' mutant, with poor grain quality, including chalky endosperms, abnormal morphology and loose arrangement of starch granules, and lower starch content but higher protein content in grains. The poor grain quality of Oat-like rice was found to be caused by the mutated OsMADS1 Olr allele through mapping-by-sequencing analysis and transgenic experiments. OsMADS1 protein is highly expressed in florets and developing seeds. Both OsMADS1-eGFP and OsMADS1 Olr -eGFP fusion proteins are localized in the nucleus. Moreover, seed-specific RNAi of OsMADS1 also caused decreased grain quality in transgenic lines, such as the Oat-like rice. Further transcriptomic profiling between Oat-like rice and Nipponbare grains revealed that OsMADS1 regulates gene expressions and regulatory networks of starch and storage protein metabolisms in rice grains, hereafter regulating rice quality. In conclusion, our results not only reveal the crucial role and preliminary mechanism of OsMADS1 in regulating rice grain quality but also highlight the application potentials of OsMADS1 and the target gene seed-specific RNAi system in improving rice grain quality by molecular breeding.

Salt-alkali stress threatens the resilience to variable environments and thus the grain yield of rice. However, how rice responds to salt-alkali stress at the molecular level is poorly understood. Here, we report isolation of a novel salt-alkali-tolerant rice (SATR) by screening more than 700 germplasm accessions. Using 93-11, a widely grown cultivar, as a control, we characterized SATR in response to strong salt-alkali stress (SSAS). SATR exhibited SSAS tolerance higher than 93-11, as indicated by a higher survival rate, associated with higher peroxidase activity and total soluble sugar content but lower malonaldehyde accumulation. A transcriptome study showed that cell wall biogenesis-related pathways were most significantly enriched in SATR relative to 93-11 upon SSAS. Furthermore, higher induction of gene expression in the cell wall matrix polysaccharide biosynthesis pathway, coupled with higher accumulations of hemicellulose and pectin as well as measurable physio-biochemical adaptive responses, may explain the strong SSAS tolerance in SATR. We mapped SSAS tolerance to five genomic regions in which 35 genes were candidates potentially governing SSAS tolerance. The 1,4-β-D-xylan synthase gene OsCSLD4 in hemicellulose biosynthesis pathway was investigated in details. The OsCSLD4 function-disrupted mutant displayed reduced SSAS tolerance, biomass and grain yield, whereas the OsCSLD4 overexpression lines exhibited increased SSAS tolerance. Collectively, this study not only reveals the potential role of cell wall matrix polysaccharides in mediating SSAS tolerance, but also highlights applicable value of OsCSLD4 and the large-scale screening system in developing SSAS-tolerant rice.

The enriched collagens in the extracellular matrix (ECM) of breast cancer substantially impede drug delivery. Halofuginone (HF), a potent antifibrotic agent, was effective to deplete the collagens and remodel the ECM by inhibiting the TGFβ pathway. However, the application of HF was hindered by its strong liver toxicity. Herein, mesoporous platinum (mPt) nanoparticles were constructed to load HF as theranostic nanoplatforms. mPt had a uniform spherical structure with a diameter of 79.83 ± 6.97 nm and an average pore diameter of 20 nm and exhibited good photothermal conversion efficiency of 62.4%. The obtained HF-loaded nanoplatform (PEG@mPt-HF) showed enhanced cytotoxicity through the combination of photothermal therapy and the anti-TGFβ effect induced by HF. The animal imaging and histochemical assays confirmed the PEG@mPt-HF could efficiently deliver HF to tumors (monitored by CT) and remodel the ECM by TGFβ pathway inhibition, which resulted in increased anti-cancer efficacy. Importantly, the liver toxicity observed in HF-treated mice was negligible in those treated by PEG@mPt-HF. Overall, this study designed a theranostic nanoplatform to remodel the ECM with remarkably reduced systematic toxicity and enhance the therapeutic efficacy through combination treatment., Competing Interests: The authors declare no competing financial or non‐financial interests., (© 2022 The Authors. Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.)

Blockade of programmed cell death 1 ligand (PD-L1) has been used to treat triple-negative breast cancer (TNBC), and various strategies are under investigation to improve the treatment response rate. Inhibition of glutamine metabolism can reduce the massive consumption of glutamine by tumor cells and meet the demand for glutamine by lymphocytes in tumors, thereby improving the anti-tumor effect on the PD-L1 blockade therapy. Here, molybdenum disulfide (MoS 2 ) was employed to simultaneously deliver anti-PDL1 antibody (aPDL1) and V9302 to boost the anti-tumor immune response in TNBC cells. The characterization results show that MoS 2 has a dispersed lamellar structure with a size of about 181 nm and a size of 232 nm after poly (L-lysine) (PLL) modification, with high stability and biocompatibility. The loading capacity of aPDL1 and V9302 are 3.84% and 24.76%, respectively. V9302 loaded MoS 2 (MoS 2 -V9302) can effectively kill 4T1 cells and significantly reduce glutamine uptake of tumor cells. It slightly increases CD8 + cells in the tumor and promotes CD8 + cells from the tumor edge into the tumor core. In vivo studies demonstrate that the combination of aPDL1 and V9302 (MoS 2 -aPDL1-V9302) can strongly inhibit the growth of TNBC 4T1 tumors. Interestingly, after the treatment of MoS 2 -aPDL1-V9302, glutamine levels in tumor interstitial fluid increased. Subsequently, subtypes of cytotoxic T cells (CD8 + ) in the tumors were analyzed according to two markers of T cell activation, CD69, and CD25, and the results reveal a marked increase in the proportion of activated T cells. The levels of cytokines in the corresponding tumor interstitial fluid are also significantly increased. Additionally, during the treatment, the body weights of the mice remain stable, the main indicators of liver and kidney function in the blood do not increase significantly, and there are no obvious lesions in the main organs, indicating low systemic toxicity. In conclusion, our study provides new insights into glutamine metabolism in the tumor microenvironment affects immune checkpoint blockade therapy in TNBC, and highlights the potential clinical implications of combining glutamine metabolism inhibition with immune checkpoint blockade in the treatment of TNBC., (© 2022. The Author(s).)

A K 2 S 2 O 8 -promoted oxidative tandem cyclization of primary alcohols with 2-aminobenzamides to synthesize quinazolinones was successfully achieved under undivided electrolytic conditions without a transition metal and base. The key feature of this protocol is the utilization of K 2 S 2 O 8 as an inexpensive and easy-to-handle radical surrogate that can effectively promote the reaction via a simple procedure, leading to the formation of nitrogen heterocycles via direct oxidative cyclization at room temperature in a one-pot procedure under constant current. Owing to the use of continuous-flow electrochemical setups, this green, mild and practical electrosynthesis features high efficiency and excellent functional group tolerance and is easy to scale up., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)