A Tumor Environment-Activated Photosensitized Biomimetic Nanoplatform for Precise Photodynamic Immunotherapy of Colon Cancer.

Aggressive nature of colon cancer and current imprecise therapeutic scenarios simulate the development of precise and effective treatment strategies. To achieve this, a tumor environment-activated photosensitized biomimetic nanoplatform (PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM) is fabricated by encapsulating metal-organic framework loaded with developed photosensitizer PEG2000-SiNcTI-Ph and immunoadjuvant CpG oligodeoxynucleotide within fusion cell membrane expressing programmed death protein 1 (PD-1) and cluster of differentiation 47 (CD47). By stumbling across, systematic evaluation, and deciphering with quantum chemical calculations, a unique attribute of tumor environment (low pH plus high concentrations of adenosine 5'-triphosphate (ATP))-activated photodynamic effect sensitized by long-wavelength photons is validated for PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM, advancing the precision of cancer therapy. Moreover, PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM evades immune surveillance to target CT26 colon tumors in mice mediated by CD47/signal regulatory proteins α (SIRPα) interaction and PD-1/programmed death ligand 1 (PD-L1) interaction, respectively. Tumor environment-activated photodynamic therapy realized by PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM induces immunogenic cell death (ICD) to elicit anti-tumor immune response, which is empowered by enhanced dendritic cells (DC) uptake of CpG and PD-L1 blockade contributed by the nanoplatform. The photodynamic immunotherapy efficiently combats primary and distant CT26 tumors, and additionally generates immune memory to inhibit tumor recurrence and metastasis. The nanoplatform developed here provides insights for the development of precise cancer therapeutic strategies.

A patient-specific lung cancer assembloid model with heterogeneous tumor microenvironments.

Cancer models play critical roles in basic cancer research and precision medicine. However, current in vitro cancer models are limited by their inability to mimic the three-dimensional architecture and heterogeneous tumor microenvironments (TME) of in vivo tumors. Here, we develop an innovative patient-specific lung cancer assembloid (LCA) model by using droplet microfluidic technology based on a microinjection strategy. This method enables precise manipulation of clinical microsamples and rapid generation of LCAs with good intra-batch consistency in size and cell composition by evenly encapsulating patient tumor-derived TME cells and lung cancer organoids inside microgels. LCAs recapitulate the inter- and intratumoral heterogeneity, TME cellular diversity, and genomic and transcriptomic landscape of their parental tumors. LCA model could reconstruct the functional heterogeneity of cancer-associated fibroblasts and reflect the influence of TME on drug responses compared to cancer organoids. Notably, LCAs accurately replicate the clinical outcomes of patients, suggesting the potential of the LCA model to predict personalized treatments. Collectively, our studies provide a valuable method for precisely fabricating cancer assembloids and a promising LCA model for cancer research and personalized medicine.

Phosphorylated SHMT2 Regulates Oncogenesis Through m6A Modification in Lung Adenocarcinoma.

Targeting cancer-specific metabolic processes is a promising therapeutic strategy. Here, this work uses a compound library that directly inhibits metabolic enzymes to screen the potential metabolic targets in lung adenocarcinoma (LUAD). SHIN1, the specific inhibitor of serine hydroxymethyltransferase 1/2 (SHMT1/2), has a highly specific inhibitory effect on LUAD cells, and this effect depends mainly on the overexpression of SHMT2. This work clarifies that mitogen-activated protein kinase 1 (MAPK1)-mediated phosphorylation at Ser90 is the key mechanism underlying SHMT2 upregulation in LUAD and that this phosphorylation stabilizes SHMT2 by reducing STIP1 homology and U-box containing protein 1 (STUB1)-mediated ubiquitination and degradation. SHMT2-Ser90 dephosphorylation decreases S-adenosylmethionine levels in LUAD cells, resulting in reduced N6-methyladenosine (m6A) levels in global RNAs without affecting total protein or DNA methylation. Methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and RNA sequencing (RNA-Seq) analyses further demonstrate that SHMT2-Ser90 dephosphorylation accelerates the RNA degradation of oncogenic genes by reducing m6A modification, leading to the inhibition of tumorigenesis. Overall, this study elucidates a new regulatory mechanism of SHMT2 during oncogenesis and provides a theoretical basis for targeting SHMT2 as a therapeutic target in LUAD.

scCancer2: data-driven in-depth annotations of the tumor microenvironment at single-level resolution.

SUMMARY: Single-cell RNA-seq (scRNA-seq) is a powerful technique for decoding the complex cellular compositions in the tumor microenvironment (TME). As previous studies have defined many meaningful cell subtypes in several tumor types, there is a great need to computationally transfer these labels to new datasets. Also, different studies used different approaches or criteria to define the cell subtypes for the same major cell lineages. The relationships between the cell subtypes defined in different studies should be carefully evaluated. In this updated package scCancer2, designed for integrative tumor scRNA-seq data analysis, we developed a supervised machine learning framework to annotate TME cells with annotated cell subtypes from 15 scRNA-seq datasets with 594 samples in total. Based on the trained classifiers, we quantitatively constructed the similarity maps between the cell subtypes defined in different references by testing on all the 15 datasets. Secondly, to improve the identification of malignant cells, we designed a classifier by integrating large-scale pan-cancer TCGA bulk gene expression datasets and scRNA-seq datasets (10 cancer types, 175 samples, 663 857 cells). This classifier shows robust performances when no internal confidential reference cells are available. Thirdly, scCancer2 integrated a module to process the spatial transcriptomic data and analyze the spatial features of TME. AVAILABILITY AND IMPLEMENTATION: The package and user documentation are available at http://lifeome.net/software/sccancer2/ and https://doi.org/10.5281/zenodo.10477296.

The spatial and single-cell analysis reveals remodeled immune microenvironment induced by synthetic oncolytic adenovirus treatment.

Oncolytic viruses are multifaceted tumor killers, which can function as tumor vaccines to boost systemic antitumor immunity. In previous study, we rationally designed a synthetic oncolytic adenovirus (SynOV) harboring a synthetic gene circuit, which can kill tumors in mouse hepatocellular carcinoma (HCC) models. In this study, we demonstrated that SynOV could sense the tumor biomarkers to lyse tumors in a dosage-dependent manner, and killed PD-L1 antibody resistant tumor cells in mouse model. Meanwhile, we observed SynOV could cure liver cancer and partially alleviate the liver cancer with distant metastasis by activating systemic antitumor immunity. To understand its high efficacy, it is essential to explore the cellular and molecular features of the remodeled tumor microenvironment (TME). By combining spatial transcriptome sequencing and single-cell RNA sequencing, we successfully depicted the remodeled TME at single cell resolution. The state transition of immune cells and stromal cells towards an antitumor and normalized status exemplified the overall cancer-suppressive TME after SynOV treatment. Specifically, SynOV treatment increased the proportion of CD8+ T cells, enhanced the cell-cell communication of Cxcl9-Cxcr3, and normalized the Kupffer cells and macrophages in the TME. Furthermore, we observed that SynOV could induce distant responses to reduce tumor burden in metastatic HCC patient in the Phase I clinical trial. In summary, our results suggest that SynOV can trigger systemic antitumor immunity to induce CD8+ T cells and normalize the abundance of immune cells to remodel the TME, which promises a powerful option to treat HCC in the future.

SUCLG2 Regulates Mitochondrial Dysfunction through Succinylation in Lung Adenocarcinoma.

Mitochondrial dysfunction and abnormal energy metabolism are major features of cancer. However, the mechanisms underlying mitochondrial dysfunction during cancer progression are far from being clarified. Here, it is demonstrated that the expression level of succinyl-coenzyme A (CoA) synthetase GDP-forming subunit ß (SUCLG2) can affect the overall succinylation of lung adenocarcinoma (LUAD) cells. Succinylome analysis shows that the deletion of SUCLG2 can upregulate the succinylation level of mitochondrial proteins and inhibits the function of key metabolic enzymes by reducing either enzymatic activity or protein stability, thus dampening mitochondrial function in LUAD cells. Interestingly, SUCLG2 itself is also succinylated on Lys93, and this succinylation enhances its protein stability, leading to the upregulation of SUCLG2 and promoting the proliferation and tumorigenesis of LUAD cells. Sirtuin 5 (SIRT5) desuccinylates SUCLG2 on Lys93, followed by tripartite motif-containing protein 21 (TRIM21)-mediated ubiquitination through K63-linkage and degradation in the lysosome. The findings reveal a new role for SUCLG2 in mitochondrial dysfunction and clarify the mechanism of the succinylation-mediated protein homeostasis of SUCLG2 in LUAD, thus providing a theoretical basis for developing anti-cancer drugs targeting SUCLG2.

STUB1-mediated ubiquitination regulates the stability of GLUD1 in lung adenocarcinoma.

The dysregulation of glutamine metabolism provides survival advantages for tumors by supplementing tricarboxylic acid cycle. Glutamate dehydrogenase 1 (GLUD1) is one of the key enzymes in glutamine catabolism. Here, we found that enhanced protein stability was the key factor for the upregulation of GLUD1 in lung adenocarcinoma. We discovered that GLUD1 showed a high protein expression in lung adenocarcinoma cells or tissues. We elucidated that STIP1 homology and U-box-containing protein 1 (STUB1) was the key E3 ligase responsible for ubiquitin-mediated proteasomal degradation of GLUD1. We further showed that lysine 503 (K503) was the main ubiquitination site of GLUD1, inhibiting the ubiquitination at this site promoted the proliferation and tumor growth of lung adenocarcinoma cells. Taken together, this study clarifies the molecular mechanism of GLUD1 in maintaining protein homeostasis in lung adenocarcinoma, which provides a theoretical basis for the development of anti-cancer drugs targeting GLUD1.

Amino acid metabolism regulated by lncRNAs: the propellant behind cancer metabolic reprogramming.

Metabolic reprogramming is one of the main characteristics of cancer cells and plays pivotal role in the proliferation and survival of cancer cells. Amino acid is one of the key nutrients for cancer cells and many studies have focused on the regulation of amino acid metabolism, including the genetic alteration, epigenetic modification, transcription, translation and post-translational modification of key enzymes in amino acid metabolism. Long non-coding RNAs (lncRNAs) are composed of a heterogeneous group of RNAs with transcripts of more than 200 nucleotides in length. LncRNAs can bind to biological molecules such as DNA, RNA and protein, regulating the transcription, translation and post-translational modification of target genes. Now, the functions of lncRNAs in cancer metabolism have aroused great research interest and significant progress has been made. This review focuses on how lncRNAs participate in the reprogramming of amino acid metabolism in cancer cells, especially glutamine, serine, arginine, aspartate, cysteine metabolism. This will help us to better understand the regulatory mechanism of cancer metabolic reprogramming and provide new ideas for the development of anti-cancer drugs. Video Abstract.

ARHGEF3 regulates the stability of ACLY to promote the proliferation of lung cancer.

Rho GTPases play an essential role in many cellular processes, including cell cycle progress, cell motility, invasion, migration, and transformation. Several studies indicated that the dysregulation of Rho GTPase signaling is closely related to tumorigenesis. Rho GEFs considered being positive regulators of Rho GTPase, promoting the dissociation of Rho protein from GDP and binding to GTP, thus activating the downstream signaling pathway. Herein, we demonstrated that ARHGEF3, a member of the Rho GEFs family, played an important role in non-small cell lung cancer (NSCLC). We found that ARHGEF3 was highly expressed in non-small cell lung cancer and facilitated cancer cell proliferation of NSCLC cells in vitro and in vivo. Further studies demonstrated that ARHGEF3 enhanced the protein homeostasis of ATP-citrate lyase (ACLY) by reducing its acetylation on Lys17 and Lys86, leading to the dissociation between ACLY and its E3 ligase-NEDD4. Interestingly, this function of ARHGEF3 on the protein homeostasis of ACLY was independent of its GEF activity. Taken together, our findings uncover a novel function of ARHGEF3, suggesting that ARHGEF3 is a promising therapeutic target in non-small cell lung cancer.

3D Bioprinted GelMA-Nanoclay Hydrogels Induce Colorectal Cancer Stem Cells Through Activating Wnt/ß-Catenin Signaling.

Cancer stem cells (CSCs) are a rare cell population in tumors that are responsible for tumor recurrence and metastasis. They are a priority as therapeutic targets, however, assays targeting CSCs have been limited by expanding and maintaining CSCs in vitro. Here, the authors find that gelatin methacryloyl (GelMA)-nanoclay hybrid hydrogels can induce and enrich colorectal CSCs assisted by three-dimensional (3D) bioprinting. The presence of the nanoclay increases the printability, Young's modulus, pore size, and cytocompatibility of the hydrogels. Bioprinted GelMA-nanoclay hydrogels promote the formation of spheroids expressing elevated levels of the stemness markers LGR5, CD133, CD26, and SOX2. Cancer cells grown in GelMA-nanoclay hydrogel possess higher self-renewal and differentiation capacity in vitro and higher tumorigenic capacity in vivo. GelMA-nanoclay hydrogels induce CSCs by stimulating the activation of the Wnt/ß-catenin signaling pathway. Further studies demonstrate that spheroids from GelMA-nanoclay hydrogels possess increased stemness, higher consistency, yield, and sensitivity to the anti-CSC compounds compared to the classic CSC-enrichment model. Collectively, this study may provide a valuable biomaterial and method for inducing and enriching CSCs, to facilitate the effective CSC-targeting drug screening.

USP14 regulates cell cycle progression through deubiquitinating CDK1 in breast cancer.

Abnormal proliferation and cell cycle perturbation are the main hallmarks of breast cancer. Cyclin-dependent kinase 1 (CDK1) is one of the key kinases for cell transition from the G2 phase to M phase during the cell cycle progression. However, little is known about the degradation mechanisms of CDK1. USP14 (ubiquitin-specific processing protease 14) is an important proteasome-associated deubiquitinase that is critical for proteome homeostasis and plays a crucial role in the initiation and development of cancer. In this study, we find that USP14 shows high expression in breast cancer cells and results in the abnormal proliferation of cancer cells. Furthermore, we examine cell cycle distribution by flow cytometry and find that inhibition of USP14 causes cell cycle arrest in G2/M phase. As CDK1 is the key kinase in G2/M phase, we detect the interaction between USP14 and CDK1 and the effect of USP14 on the deubiquitination of CDK1. The results reveal that USP14 interacts with CDK1 and stabilizes CDK1 by deubiquitinating K48-linked ubiquitination. In conclusion, our findings reveal an indispensable role of USP14 in regulating cell cycle progression by stabilizing CDK1 in breast cancer, suggesting that USP14 may be used as a potential therapeutic target in breast cancer therapy.

Simultaneous blockage of contextual TGF-ß by cyto-pharmaceuticals to suppress breast cancer metastasis.

It remains challenging to treat tumor metastasis currently in the light of multiple cascade processes of tumor metastasis. Additionally, multiple clinical drugs for metastasis have quite limited therapeutic potential and even facilitate metastasis in preclinical models. Thus, potential metastasis targets and novel metastasis-directed drugs are urgently needed to be further developed. Herein, transforming growth factor-ß (TGF-ß) is verified to contribute to lung metastasis in a context-dependent manner in the 4T1 orthotopic tumor-bearing mice model, which induces epithelial-mesenchymal-transition (EMT) to promote tumor dissemination from the primary site and dampens the anti-tumor response of neutrophils to support tumor colonization at the metastatic niche. In view of neutrophils' superior tropism towards both inflammatory primary tumor and metastatic niche, SB525334, a TGF-ß receptor inhibitor, is loaded into cationic liposome (SBLP) which is subsequently incorporated into neutrophils to yield the cyto-pharmaceuticals (SBLP/NE). The systemically infused SBLP/NE can simultaneously migrate into both primary and metastatic sites, then release SB525334 in response to tumor stimuli, and contextually inhibit TGF-ß-mediated-EMT and phenotype reversal of infiltrated neutrophils, showing substantial metastasis suppression efficacy without causing any detectable toxicities. This project shifts the paradigm for metastasis suppression therapy by simultaneous blockage of contextual TGF-ß using metastatic-cascades-targeting neutrophil cyto-pharmaceuticals.

Combination of metabolic intervention and T cell therapy enhances solid tumor immunotherapy.

Treatment of solid tumors with T cell therapy has yielded limited therapeutic benefits to date. Although T cell therapy in combination with proinflammatory cytokines or immune checkpoints inhibitors has demonstrated preclinical and clinical successes in a subset of solid tumors, unsatisfactory results and severe toxicities necessitate the development of effective and safe combinatorial strategies. Here, the liposomal avasimibe (a metabolism-modulating drug) was clicked onto the T cell surface by lipid insertion without disturbing the physiological functions of the T cell. Avasimibe could be restrained on the T cell surface during circulation and extravasation and locally released to increase the concentration of cholesterol in the T cell membrane, which induced rapid T cell receptor clustering and sustained T cell activation. Treatment with surface anchor-engineered T cells, including mouse T cell receptor transgenic CD8+ T cells or human chimeric antigen receptor T cells, resulted in superior antitumor efficacy in mouse models of melanoma and glioblastoma. Glioblastoma was completely eradicated in three of the five mice receiving surface anchor-engineered chimeric antigen receptor T cells, whereas mice in other treatment groups survived no more than 64 days. Moreover, the administration of engineered T cells showed no obvious systemic side effects. These cell-surface anchor-engineered T cells hold translational potential because of their simple generation and their safety profile.

MYH9 Key Amino Acid Residues Identified by the Anti-Idiotypic Antibody to Porcine Reproductive and Respiratory Syndrome Virus Glycoprotein 5 Involve in the Virus Internalization by Porcine Alveolar Macrophages.

MYH9 has been identified as an indispensable cellular protein for porcine reproductive and respiratory syndrome virus (PRRSV) entry into permissive cells using the monoclonal anti-idiotypic antibody (Mab2-5G2) recognizing an antibody that specifically interacts with PRRSV glycoprotein 5 (GP5). More recently, we found that Mab2-5G2 interacted with the MYH9 C-terminal domain, designated PRA, which is required for PRRSV internalization. In this study, we demonstrate that blocking of MYH9 with Mab2-5G2 significantly diminished PRRSV internalization by porcine alveolar macrophage (PAM) via interruption of direct interaction between GP5 and MYH9, and thus remarkably inhibited subsequent infection of PAMs by PRRSV-2 isolates. Moreover, the three-dimensional structure of the Mab2-5G2 Fab-PRA complex determined via homology modeling predicted potential docking sites required for PRRSV internalization. Further analysis of Mab2-5G2-binding sites within PRA highlighted that the amino acids E1670, K1673, E1679, and I1683 in PRA are the key Mab2-5G2-binding residues. Notably, recombinant PRA protein blocked the interaction between PRRSV GP5 and cellular MYH9 by preventing translocation of MYH9 from the cytoplasm to the cell membrane, an essential step for PRRSV virion internalization. Meanwhile, porcine cell line permissive for PRRSV bearing point mutation of E1670A in MYH9 demonstrated reduced susceptibility for PRRSV infection. In conclusion, this work increases understanding of both PRRSV pathogenesis and the mechanistic role played by MYH9 in PRRSV infection.

[Study of the influence of nodal liquefaction in measurement of the ADC value of OSCC metastatic lymph nodes in patients with oral squamous cell carcinoma].

PURPOSE: To study the influence of nodal liquefaction portion in the measurement of the ADC value of metastatic lymph nodes in patients with oral squamous cell carcinoma (OSCC) on DW-MRI images. METHODS: According to the postoperative histopathological examination results, the DW-MRI data of 25 OSCC patients was analyzed. The ADC values of both solid portions of metastatic lymph nodes and the whole metastatic lymph nodes with internal liquefaction were selected and measured. Further comparison between the 2 groups was processed for 2 independent samples t test with SPSS 17.0 software package. RESULTS: Eleven patients out of all cases were diagnosed with cervical lymph node metastasis, and 15 metastatic lymph nodes were detected, among which 8 metastatic lymph nodes had obvious internal liquefaction. The average ADC values of solid portions of metastatic lymph nodes (group SMLN) and the whole metastatic lymph nodes with internal liquefaction (LMLN group) ADC were (872.1 ± 22.65) × 10⁻6 mm²/s (n=15) and (1073 ± 16.99) × 10⁻6 mm²/s (n=8), respectively. Two independent samples t test showed statistically significant difference of ADC values between group SMLN and group LMLN (P<0.05). CONCLUSIONS: The internal liquefaction in OSCC metastatic lymph nodes can lead to an increased average ADC value. If the measurement of OSCC metastatic lymph nodes includes obvious liquefaction portions, it may reduce the diagnostic accuracy of DW-MRI for discrimination of lymph node metastasis.