Global profiling of transcriptome, proteome and 2-hydroxyisobutyrylome in radioresistant lung adenocarcinoma cell.

Radioresistance contributes to metastasis and recurrence in non-small cell lung cancer (NSCLC) patients. However, the underlying mechanism remains unclear. To provide novel clues, a complete multi-omics map of a radioresistant cancer cell line has been profiled. In this article, a lung adenocarcinoma cell line, radioresistant A549 (RA549), was generated by exposure to a series of irradiation. Subsequently, we adopted transcriptome, quantitative proteome and lysine 2-hydroxyisobutyrylome to construct a differential profile on the transcriptional to post-tanslational levels on A549 and RA549 cell lines, respectively. Our analysis revealed 920 significantly differentially expressed genes and 699 proteins. Furthermore, 2-hydroxyisobutyrylome identified 30,089 Khib modified sites on 4635 proteins, indicating that Khib modifications play vital role in regulating NSCLC radioresistance. Multi-omics combined analysis identified 19 significantly differentially expressed genes/proteins in total. Meanwhile, we found that EGFR, a well-known lung cancer-related receptor, was upregulated at both the protein and Khib modification levels in RA549. Further gain/loss of function experiments showed that Khib modified EGFR level positively correlates with NSCLC cell radioresistance. Taken together, our findings report that Khib-modified proteins enhanced resistance to radiation and represent promising therapeutic targets.

Single-cell RNA sequencing reveals recruitment of the M2-like CCL8high macrophages in Lewis lung carcinoma-bearing mice following hypofractionated radiotherapy.

BACKGROUND: Tumor-associated macrophages (TAMs) play a pivotal role in reshaping the tumor microenvironment following radiotherapy. The mechanisms underlying this reprogramming process remain to be elucidated. METHODS: Subcutaneous Lewis lung carcinoma (LLC) murine model was treated with hypofrationated radiotherapy (8 Gy × 3F). Single-cell RNA sequencing was utilized to identify subclusters and functions of TAMs. Multiplex assay and enzyme-linked immunosorbent assay (ELISA) were employed to measure serum chemokine levels. Bindarit was used to inhibit CCL8, CCL7, and CCL2. The infiltration of TAMs after combination treatment with hypofractionated radiotherapy and Bindarit was quantified with flow cytometry, while the influx of CD206 and CCL8 was assessed by immunostaining. RESULTS: Transcriptome analysis identified a distinct subset of M2-like macrophages characterized by elevated Ccl8 expression level following hypofractionated radiotherapy in LLC-bearing mice. Remarkbly, hypofractionated radiotherapy not only promoted CCL8high macrophages infiltration but also reprogrammed them by upregulating immunosuppressive genes, thereby fostering an immunosuppressive tumor microenvironment. Additioinally, hypofractionated radiotherapy enhanced the CCL signaling pathway, augmenting the pro-tumorigenic functions of CCL8high macrophages and boosting TAMs recruitment. The adjunctive treatment combining hypofractionated radiotherapy with Bindarit effectively reduced M2 macrophages infiltration and prolonged the duration of local tumor control. CONCLUSIONS: Hypofractionated radiotherapy enhances the infiltration of CCL8high macrophages and amplifies their roles in macrophage recruitment through the CCL signaling pathway, leading to an immunosuppressive tumor microenvironment. These findings highlight the potential of targeting TAMs and introduces a novel combination to improve the efficacy of hypofractionated radiotherapy.

Distinct accumulation of nanoplastics in human intestinal organoids.

Plastic particles, especially nanoplastics, represent an emerging concern of threat to human health, oral uptake is an important pathway for the plastic particles ingestion by human. While their fate and adverse effects in animal gastrointestinal tract are increasingly investigated, knowledge about their uptake and toxicity in human intestine is still limited. Here, by exposing human intestinal organoids to polystyrene nanoplastics (PS-NPs, ~50 nm in size) with concentrations of 10 and 100 µg/mL, we present evidence of their distinct accumulation in various type cells in intestinal organoids, then causing the cell apoptosis and inflammatory response. Our results further revealed that the effective inhibition of PS-NPs accumulation in secretive cells through co-exposure to a clathrin-mediated endocytosis inhibitor (chlorpromazine), and proved the essential role of active endocytosis in the PS-NPs uptaking into enterocyte cells. Our work not only elucidated the potential uptake and toxicity of PS-NPs in human intestinal cells and the underlying mechanism, but also provide a potential therapeutic approach to relieve the toxicity of PS-NPs to human through the endocytosis inhibition.