Cold to Hot: Tumor Immunotherapy by Promoting Vascular Normalization Based on PDGFB Nanocomposites.

Immunotherapy is a promising cancer therapeutic strategy. However, the "cold" tumor immune microenvironment (TIME), characterized by insufficient immune cell infiltration and immunosuppressive status, limits the efficacy of immunotherapy. Tumor vascular abnormalities due to defective pericyte coverage are gradually recognized as a profound determinant in "cold" TIME establishment by hindering immune cell trafficking. Recently, several vascular normalization strategies by improving pericyte coverage have been reported, whereas have unsatisfactory efficacy and high rates of resistance. Herein, a combinatorial strategy to induce tumor vasculature-targeted pericyte recruitment and zinc ion-mediated immune activation with a platelet-derived growth factor B (PDGFB)-loaded, cyclo (Arg-Gly-Asp-D-Phe-Lys)-modified zeolitic imidazolate framework 8 (PDGFB@ZIF8-RGD) nanoplatform is proposed. PDGFB@ZIF8-RGD effectively induced tumor vascular normalization, which facilitated trafficking and infiltration of immune effector cells, including natural killer (NK) cells, M1-like macrophages and CD8+ T cells, into tumor microenvironment. Simultaneously, vascular normalization promoted the accumulation of zinc ions inside tumors to trigger effector cell immune activation and effector molecule production. The synergy between these two effects endowed PDGFB@ZIF8-RGD with superior capabilities in reprogramming the "cold" TIME to a "hot" TIME, thereby initiating robust antitumor immunity and suppressing tumor growth. This combinatorial strategy for improving immune effector cell infiltration and activation is a promising paradigm for solid tumor immunotherapy.

An extra-erythrocyte role of haemoglobin body in chondrocyte hypoxia adaption.

Although haemoglobin is a known carrier of oxygen in erythrocytes that functions to transport oxygen over a long range, its physiological roles outside erythrocytes are largely elusive1,2. Here we found that chondrocytes produced massive amounts of haemoglobin to form eosin-positive bodies in their cytoplasm. The haemoglobin body (Hedy) is a membraneless condensate characterized by phase separation. Production of haemoglobin in chondrocytes is controlled by hypoxia and is dependent on KLF1 rather than the HIF1/2α pathway. Deletion of haemoglobin in chondrocytes leads to Hedy loss along with severe hypoxia, enhanced glycolysis and extensive cell death in the centre of cartilaginous tissue, which is attributed to the loss of the Hedy-controlled oxygen supply under hypoxic conditions. These results demonstrate an extra-erythrocyte role of haemoglobin in chondrocytes, and uncover a heretofore unrecognized mechanism in which chondrocytes survive a hypoxic environment through Hedy.

Cuproptosis-related gene PDHX and heat stress-related HSPD1 as potential key drivers associated with cell stemness, aberrant metabolism and immunosuppression in esophageal carcinoma.

BACKGROUND: Heat stress is fundamental to esophageal carcinoma (ESCA) oncogenesis and progression. Heat stress damages epithelial structure, causing aberrant 'cell death-repair' patterns of esophagus cells and thereby driving tumor occurrence and progression. However, due to the distinctive functions and crosstalk of regulatory cell death (RCD) patterns, the specific cell deaths in ESCA malignancy are still unclear. METHODS: We analyzed the key regulatory cell death genes involved in heat stress and ESCA progression by using The Cancer Genome Atlas-ESCA database. The least absolute shrinkage and selection operator (LASSO) algorithm was used to filter the key genes. The one-class logistic regression (OCLR) and quanTIseq methods were used to evaluate the cell stemness and immune cell infiltration in ESCA samples. Cell counting kit-8 (CCK8) and wound healing assays were performed to assess the proliferation and migration of cells. RESULTS: We found that cuproptosis may be a potential risk factor of heat stress-related ESCA. Two interrelated genes, HSPD1 and PDHX, were associated with heat stress and cuproptosis and played a role in cell survival, proliferation, migration, metabolism and immunosuppression. CONCLUSIONS: We found that cuproptosis promoted ESCA related to heat stress, offering a new therapeutic opportunity to treat this malignant disorder.

A cuproptosis-related long non-coding RNA signature to predict the prognosis and immune microenvironment characterization for lung adenocarcinoma.

Background: Cuproptosis or copper-dependent cell death is a newly identified non-apoptotic cell death pathway which plays a critical role in the development of multiple cancers. Long non-coding RNAs (lncRNAs) are increasingly recognized as crucial regulators of programmed cell death and lung adenocarcinoma (LUAD) development, and a comprehensive understanding of cuproptosis-related lncRNAs may improve prognosis prediction of LUAD. However, few studies have explored the association of cuproptosis-related lncRNAs with the prognosis of LUAD. Methods: The RNA sequencing data and corresponding clinical information of patients were extracted from The Cancer Genome Atlas (TCGA) database. Five hundred LUAD patients were randomly divided into a training (n=250) and a testing cohort (n=250). Pearson correlations were performed to identify cuproptosis-related lncRNAs, and univariate Cox regression was performed to screen prognostic lncRNAs. A cuproptosis-related lncRNAs prognostic signature (CLPS) was constructed by the least absolute shrinkage and selection operator Cox regression. Kaplan-Meier analysis, receiver operating characteristic curves, and multivariate Cox regression were performed to verify the prognostic performance of CLPS. Additionally, immune cell infiltration was estimated using the single-sample gene-set enrichment analysis. pRRophetic algorithm and Tumor Immune Dysfunction and Exclusion algorithm were used to assess the immunotherapy and chemotherapy response, respectively. Results: CLPS was established based on 61 cuproptosis-related prognostic lncRNAs and exhibited a satisfactory performance predicting LUAD patients' survival (area under the curve at 1, 3, 5 years was 0.784, 0.749, 0.775, respectively). multivariate Cox analysis confirmed the independent prognostic effect of CLPS (hazard ratio: 1.128; 95% confidence interval: 1.071-1.189; P<0.001), and a nomogram containing it exhibited robust validity in prognostic prediction. We further demonstrated a higher CLPS-risk score was associated with lower levels of signatures including immune cell infiltration, immune activation, and immune checkpoints. Conclusions: The CLPS serves as an effective predictor for the prognosis and therapeutic responses of LUAD patients. Our findings provide promising novel biomarkers and therapeutic targets for LUAD.

Comprehensive analysis of m7G modification patterns based on potential m7G regulators and tumor microenvironment infiltration characterization in lung adenocarcinoma.

Background: The non-negligible role of epigenetic modifications in cancer development and tumor microenvironment (TME) has been demonstrated in recent studies. Nonetheless, the potential regulatory role of N7-methylguanosine (m7G) modification in shaping and impacting the TME remains unclear. Methods: A comprehensive analysis was performed to explore the m7G modification patterns based on 24 potential m7G regulators in 817 lung adenocarcinoma (LUAD) patients, and the TME landscape in distinct m7G modification patterns were evaluated. The m7G score was established based on principal component analysis (PCA) to quantify m7G modification patterns and evaluate the TME cell infiltrating characteristics of individual tumors. Further, correlation analyses of m7Gscore with response to chemotherapy and immunotherapy were performed. Results: We identified three distinct m7G modification patterns with the biological pathway enrichment and TME cell infiltrating characteristics corresponded to immune-desert, immune-inflamed and immune-excluded phenotype, respectively. We further demonstrated the m7Gscore could predict the TME infiltrating characteristics, tumor mutation burden (TMB), response to immunotherapy and chemotherapy, as well as prognosis of individual tumors. High m7Gscore was associated with increased component of immune cell infiltration, low TMB and survival advantage, while low m7Gscore was linked to decreased immune cell infiltration and increased TMB. Additionally, patients with lower m7Gscore demonstrated significant therapeutic advantages. Conclusion: This study demonstrated the regulatory mechanisms of m7G modification on TME formation and regulation of lung adenocarcinoma. Identification of individual tumor m7G modification patterns will contribute to the understanding of TME characterization and guiding more effective immunotherapy strategies.

Transcriptional and genetic alterations of cuproptosis-related genes correlated to malignancy and immune-infiltrate of esophageal carcinoma.

Esophageal carcinoma (ESCA) is a common type of cancer with high mortality. Cuproptosis is a new type of cell death and is characterized by the dependence on mitochondrial respiration and protein lipoylation. However, the potential roles of cuproptosis-related genes (CRGs) in ESCA remain elusive. Here, we systematically assessed the transcriptional and genetic alterations of CRGs in ESCA. We identified a CRGs signature for ESCA patients. A 6-CRGs signature was constructed by the least absolute shrinkage and selection operator (LASSO) regression analysis along with the univariate cox regression analysis and differential genes analysis. The CRGs score could significantly stratify ESCA patients' survival and a high CRGs score was significantly correlated with worse overall survival. Moreover, higher CRGs score indicated higher pathology grades and aberrant cell adhesion, possibly via the PI3K-AKT pathway, which could also underly their increased sensitivity to PI3K-AKT pathway inhibitors. In addition, patients with high CRGs tend to hold more mutation load and abnormal APOBEC mutation. Notably, a higher CRGs score was anomalously associated with more immune infiltration, which could explain its malignancy by increased PD-L1 stability and a higher proportion of bystander T cells. In conclusion, our report revealed the significance of cuproptosis in ESCA and may have therapeutic potential in activating the bystander T cells.

[Analysis of swelling stress and signaling pathway of human lung cancer cells].

Objective To investigate whether swelling stress exists in lung cancer cells by comparing water content and nucleus size as well as mitogen activated protein kinase (MAPK) phosphorylation activation between lung cancer tissues and corresponding paracancerous tissues. Methods Differences in water content between fresh specimens of 10 human lung adenocarcinoma, 12 lung squamous cell carcinoma, and corresponding paracancerous normal lung tissues were examined through "dry and wet" mass comparison. The expressions and phosphorylation activation of mitogen activated protein kinases JNK, ERK1/2, and p38 in 30 lung adenocarcinoma samples, 32 lung squamous cell carcinoma samples, and alveolar epithelial cells and lung bronchial epithelial cells of 10 paracancerous normal tissues samples were detected with their phosphorylated and non-phosphorylated antibodies and by immunohistochemical staining. Nucleus size differences between cancer cells from lung adenocarcinoma and lung squamous cell carcinoma samples and corresponding paracancerous normal lung alveolar epithelial cells or bronchial epithelial cells were estimated by HE staining and analyzed with image analysis software. Results The average water content of lung squamous cell carcinoma and lung adenocarcinoma samples were significantly higher than that of their corresponding paracancerous normal tissues. Immunohistochemistry showed that p38 was highly expressed in all samples of lung adenocarcinoma, lung squamous cell carcinoma, and paracancerous tissues. ERK was weakly expressed in lung adenocarcinoma and squamous cell carcinoma samples, but highly expressed in paracancerous tissues. JNK was weakly expressed in lung adenocarcinoma and paracancerous tissues. JNK, p38 MAPK, and ERK1/2 were not activated through phosphorylation in alveolar or bronchial epithelial tissues. However, JNK, not p38 or ERK1/2, was phosphorylated in lung adenocarcinoma and lung squamous cell carcinoma tissues. The average nucleus size of lung cancer cells was significantly larger than those of their corresponding paracancerous normal lung epithelial cells. Conclusion There is swelling stress in lung cancer cells, and different types of human lung cancer cells have different swelling stress signaling pathways.

A comprehensive characterization of alternative splicing events related to prognosis and the tumor microenvironment in lung adenocarcinoma.

Background: Alternative splicing (AS) is a critical mechanism of post-transcriptional regulation and has been widely reported to be associated with the tumor progression and tumor microenvironment (TME) formation. However, the role of AS in lung adenocarcinoma (LUAD) has not been clearly elucidated. This study presents a comprehensive analysis exploring the impact of AS on prognosis and TME in LUAD. Methods: The gene expression transcriptome profiles and survival data were obtained from The Cancer Genome Atlas (TCGA) database, and the splicing profiles were obtained from the TCGA SpliceSeq database. Base on prognostic AS events, a prognostic signature was constructed using Least Absolute Shrinkage and Selection Operator (LASSO) regression followed by multivariate Cox regression analysis. Survival outcomes was analyzed using the Kaplan-Meier method and the predictive performance of the signature was evaluated using receiver operating characteristic (ROC) curve analysis. Furthermore, the landscape of the TME was assessed by ESTIMATE, Microenvironment Cell Population (MCP)-counter, and single-sample Gene-Set Enrichment Analysis (ssGSEA) algorithms. Results: A total of 127 prognostic AS events with P value <0.001 from 89 genes in LUAD were confirmed. A prognostic signature was constructed based on 20 prognostic AS events. Kaplan-Meier survival analysis demonstrated that higher risk scores were associated with poorer overall survival (OS). The area under the ROC curve of risk scores predicting the 1-, 3-, and 5-year survival probability were 0.791, 0.847, and 0.832, respectively. Furthermore, significant relationship was observed between the prognostic signature and the landscape of the TME. High-risk patients had lower stromal/immune scores, higher tumor purity, and significantly decreased abundance of majority immune cells, and immune-related signatures (P<0.05). Finally, a potential regulatory mechanism of the AS events is displayed in a regulatory network. Conclusions: This research highlights the prognostic value of AS events for patients with LUAD and provide new insight into the regulation of the TME by AS. Notably, AS may affect the patient's prognosis by altering the TME. Our findings provide important guidance for the development of novel biomarkers and therapeutic targets in patients with LUAD.

Identification of Jmjd3 as an Essential Epigenetic Regulator of Hox Gene Temporal Collinear Activation for Body Axial Patterning in Mice.

Body axial patterning develops via a rostral-to-caudal sequence and relies on the temporal colinear activation of Hox genes. However, the underlying mechanism of Hox gene temporal colinear activation remains largely elusive. Here, with small-molecule inhibitors and conditional gene knockout mice, we identified Jmjd3, a subunit of TrxG, as an essential regulator of temporal colinear activation of Hox genes with its H3K27me3 demethylase activity. We demonstrated that Jmjd3 not only initiates but also maintains the temporal collinear expression of Hox genes. However, we detected no antagonistic roles between Jmjd3 and Ezh2, a core subunit of PcG repressive complex 2, during the processes of axial skeletal patterning. Our findings provide new insights into the regulation of Hox gene temporal collinear activation for body axial patterning in mice.

Disruption of Jmjd3/p16Ink4a Signaling Pathway Causes Bizarre Parosteal Osteochondromatous Proliferation (BPOP)-like Lesion in Mice.

Bizarre parosteal osteochondromatous proliferation (BPOP), or Nora's lesion, is a rare benign osteochondromatous lesion. At present, the molecular etiology of BPOP remains unclear. JMJD3(KDM6B) is an H3K27me3 demethylase and counteracts polycomb-mediated transcription repression. Previously, Jmjd3 was shown to be critical for bone development and osteoarthritis. Here, we report that conditional deletion of Jmjd3 in chondrogenic cells unexpectedly resulted in BPOP-like lesion in mice. Biochemical investigations revealed that Jmjd3 inhibited BPOP-like lesion through p16Ink4a . Immunohistochemistry and RT-qPCR assays indicated JMJD3 and p16INK4A level were significantly reduced in human BPOP lesion compared with normal subjects. This was further confirmed by Jmjd3/Ink4a double-gene knockout mice experiments. Therefore, our results indicated the pathway of Jmjd3/p16Ink4a may be essential for the development of BPOP in human. © 2021 American Society for Bone and Mineral Research (ASBMR).