PD-1+ mast cell enhanced by PD-1 blocking therapy associated with resistance to immunotherapy.

BACKGROUND: Programmed cell death protein 1 (PD-1) antibody has been approved for a variety of tumors, but its effective rate is unsatisfactory. New evidence suggests that mast cells are an important component of the tumor microenvironment and are associated with resistance to immunotherapy, but the underlying mechanism is not clear. METHODS: Bioinformatics analysis of patients with melanoma in TCGA-SKCM and GSE91061 was used to determine the prognostic value of mast cells and their association with anti-PD-1 immunotherapy. HMC-1 cells (mast cell line) and bone marrow-derived mast cells (BMMCs) were used to verify the effect of PD-1 antibody and cromolyn sodium in vitro. The mouse subcutaneous melanoma model was used to verify the effect of the PD-1 antibody on mast cells in vivo. RESULTS: Bioinformatics analysis showed that mast cells were a poor prognostic factor associated with resistance to anti-PD-1 immunotherapy. PD-1 was expressed on the mast cell membrane. The PD-1 antibody promoted the release of histamine and cytokines from mast cells via the PI3K/AKT pathway and calcium signaling pathway. The activation of mast cells induced by PD-1 antibody could be partially inhibited by cromolyn sodium. In vivo, cromolyn sodium increased the efficacy of PD-1 antibody and decreased the infiltration of mast cells and the density of microvessels. CONCLUSION: PD-1+ mast cell activated by PD-1 antibody plays a negative role in the tumor microenvironment via the enhanced function of releasing histamine and cytokines. Inhibition of mast cell may provide a new solution to solve the low response rate of anti-PD-1 immunotherapy.

miR-486 improves fibrotic activity in myocardial infarction by targeting SRSF3/p21-Mediated cardiac myofibroblast senescence.

The regulation of fibrotic activities is key to improving pathological remodelling post-myocardial infarction (MI). Currently, in the clinic, safe and curative therapies for cardiac fibrosis and improvement of the pathological fibrotic environment, scar formation and pathological remodelling post-MI are lacking. Previous studies have shown that miR-486 is involved in the regulation of fibrosis. However, it is still unclear how miR-486 functions in post-MI regeneration. Here, we first demonstrated that miR-486 targeting SRSF3/p21 mediates the senescence of cardiac myofibroblasts to improve their fibrotic activity, which benefits the regeneration of MI by limiting scar size and post-MI remodelling. miR-486-targeted silencing has high potential as a novel target to improve fibrotic activity, cardiac fibrosis and pathological remodelling.

Early moderate exercise benefits myocardial infarction healing via improvement of inflammation and ventricular remodelling in rats.

Thus far, the cellular and molecular mechanisms related to early (especially within 24 hours after acute myocardial infarct (MI)) exercise-mediated beneficial effects on MI have not yet been thoroughly established. In the present study, we demonstrated that acute MI rats that underwent early moderate exercise training beginning one day after MI showed no increase in mortality and displayed significant improvements in MI healing and ventricular remodelling, including an improvement in cardiac function, a decrease in infarct size, cardiomyocyte apoptosis, cardiac fibrosis and cardiomyocyte hypertrophy, and an increase in myocardial angiogenesis, left ventricular wall thickness and the number of cardiac telocytes in the border zone. Integrated miRNA-mRNA profiling analysis performed by the ingenuity pathway analysis system revealed that the inhibition of the TGFB1 regulatory network, activation of leucocytes and migration of leucocytes into the infarct zone comprise the molecular mechanism underlying early moderate exercise-mediated improvements in cardiac fibrosis and the pathological inflammatory response. The findings of the present study demonstrate that early moderate exercise training beginning one day after MI is safe and leads to significantly enhanced MI healing and ventricular remodelling. Understanding the mechanism behind the positive effects of this early training protocol will help us to further tailor suitable cardiac rehabilitation programmes for humans.

Which technique of positioning and immobilization is better for breast cancer patients in postmastectomy IMRT, single-pole or double-pole immobilization?

PURPOSE: Our purpose was to explore which immobilization is more suitable for clinical practice in postmastectomy intensity modulation radiotherapy, the single-pole position or the double-pole position? METHODS: Patients treated with postmastectomy intensity modulation radiotherapy were eligible. They were selected randomly for single-pole position or double-pole position. Dose-volume histogram (DVH) was used to evaluate plans. After their first radiotherapy, the physicians asked a question about the comfort level of their position. The dosimetric parameters, comfort levels, and reproducibility of the two immobilization techniques were collected and analyzed after all patients had finished the whole radiotherapy. RESULTS: Totally, 94 patients were enrolled. Of these, 54 patients were treated with the single-pole position, 28 (51.9%)had left-sided lesions. While 40 patients were treated with the double-pole position, 20 (50%) had left-sided lesions. Patients' characteristics in two groups were comparable. The single-pole and double-pole immobilizations had similar conformity (0.60 ± 0.05 vs 0.60 ± 0.06, P = 0.887) and homogeneity index (0.14 ± 0.03 vs 0.13 ± 0.03, P = 0.407). Compared to single-pole position, double-pole position typically increased the mean dose, V20 , and V30 of heart (P < 0.05). Moreover, patients in the single-pole group felt more comfortable than another group (P < 0.05). There was no difference in reproducibility between the two groups (P > 0.05). CONCLUSIONS: Single-pole position seems to be more comfortable and can reduce dose coverage to heart. Both devices allow for reproducible setup and acceptable dosimetry.

Small cell conversion complicated with hypertrophic pulmonary osteoarthropathy after targeted therapy for advanced EGFR-mutated lung adenocarcinoma: A case report.

In recent years, with the opening of the era of precision therapy, the treatment of patients with positive driver genes is a hot issue in global research. EGFR is the most common driver gene in NSCLC, with a positivity rate of 17%. Although targeted drugs for EGFR mutations can benefit this population with efficacy, target therapy resistance inevitably occurs. The presented case suggests that a patient with advanced lung adenocarcinoma with EGFR mutation who developed pathological-type conversion of small cell lung cancer complicated with the development of hypertropic pulmonary osteoarthropathy (HPOA) after 6 months of targeted therapy. This case demonstrates that early diagnosis of HPOA can predict the occurrence of target resistance and pathologic conversion in patients with positive driver genes, providing new clues for the clinical management of lung cancer.

Research progress of tumor-derived extracellular vesicles in the treatment of malignant pleural effusion.

Vesicles, also known as "microparticles", are vesicle-like structures that are released outside the cell in a "sprouting" manner when the cytoskeleton is changed during cell activation or apoptosis, with a diameter of about 100-1000 nm, and are carriers of material information exchange between cells. Tumor-derived extracellular vesicles can effectively deliver drugs to the nucleus of tumor stem cells, thus effectively killing them without toxic side effects. The underlying mechanism involves the soft nature of tumor stem cells that allows better uptake of vesicles, and the entry of drug-carrying vesicles into lysosomes and facilitation of lysosomal movement toward the nucleus to deliver drugs to the nucleus. Drug-loaded vesicles have unique advantages, such as low immunogenicity, homing targeting ability, and the ability to break through the physiological barrier to tumor therapy. Tumor-derived drug-delivery vesicles have entered clinical trials for the treatment of malignant pleural effusions. In this review, we summarized the progress of basic and clinical research on tumor cell-derived drug-loaded vesicles for the treatment of malignant pleural effusion in recent years.

Hypoxia-Induced Autophagy Is Involved in Radioresistance via HIF1A-Associated Beclin-1 in Glioblastoma Multiforme.

Radioresistance is the major factor of glioblastoma multiforme (GBM) treatment failure and relapse. Hypoxia and autophagy are linked to radioresistance and poor prognosis in solid tumors, but mechanisms remain unknown. Thus, we hypothesize that hypoxia may activate autophagy through two critical factors, HIF1A and Beclin-1, resulting in radioresistance of GBM in vitro and in vivo. In this study, we first demonstrated that HIF1A was overexpressed in GBM tissues and predicted a poor prognosis via bioinformatics. Secondly, we determined that hypoxia induced high expression of HIF1A and upregulated levels of Beclin-1 and autophagy, while HIF1A knockdown by shRNA reduced the expression of Beclin-1. Then we revealed the crosstalk and mechanisms of HIF1A-associated-Beclin-1 in three aspects: (a) transcriptional regulation, (b) protein interaction, and (c) HIF1A/BNIP3/Beclin-1 signaling pathway. Furthermore, we confirmed that silencing HIF1A enhanced the radiosensitivity of GBM in vitro and in vivo. Additionally, Beclin-1 suppression by 3-MA could reverse radioresistance induced by HIF1A under hypoxia. In conclusion, we demonstrated that hypoxia triggered autophagy via HIF1A-associated Beclin-1, resulting in radioresistance in GBM. HIF1A knockdown improved GBM radiosensitivity, and silencing Beclin-1 could reverse HIF1A-induced radioresistance under hypoxic conditions. These findings may help us comprehend the molecular underpinnings of hypoxia-induced autophagy and provide a novel perspective and prospective treatment for GBM radiosensitization.

FIBP interacts with transcription factor STAT3 to induce EME1 expression and drive radioresistance in lung adenocarcinoma.

Cancer cells inevitably develop radioresistance during lung adenocarcinoma radiotherapy. However, the mechanisms are incompletely clarified. In this study, we show that FIBP protein expression in lung adenocarcinoma tissues is upregulated and associated with worse overall survival. Functionally, we find that depletion of FIBP inhibits lung adenocarcinoma progression and radioresistance in vitro and in vivo. Moreover, we uncover that FIBP interacts with STAT3 to enhance its transcriptional activity, thereby inducing the expression of the downstream target gene EME1. Importantly, we demonstrate that the biological effects of FIBP are partially dependent on EME1 in lung adenocarcinoma. Our work reveals that FIBP modulates the STAT3/EME1 axis to drive lung cancer progression and radioresistance, indicating that targeting FIBP may be a novel intervention strategy for lung adenocarcinoma radiotherapy.

An unusual ectopic thymoma clonal evolution analysis: A case report.

Thymomas and thymic carcinomas are rare and primary tumors of the mediastinum which is derived from the thymic epithelium. Thymomas are the most common primary anterior mediastinal tumor, while ectopic thymomas are rarer. Mutational profiles of ectopic thymomas may help expand our understanding of the occurrence and treatment options of these tumors. In this report, we sought to elucidate the mutational profiles of two ectopic thymoma nodules to gain deeper understanding of the molecular genetic information of this rare tumor and to provide guidance treatment options. We presented a case of 62-year-old male patient with a postoperative pathological diagnosis of type A mediastinal thymoma and ectopic pulmonary thymoma. After mediastinal lesion resection and thoracoscopic lung wedge resection, the mediastinal thymoma was completely removed, and the patient recovered from the surgery and no recurrence was found by examination until now. Whole exome sequencing was performed on both mediastinal thymoma and ectopic pulmonary thymoma tissue samples of the patient and clonal evolution analysis were further conducted to analyze the genetic characteristics. We identified eight gene mutations that were co-mutated in both lesions. Consistent with a previous exome sequencing analysis of thymic epithelial tumor, HRAS was also observed in both mediastinal lesion and lung lesion tissues. We also evaluated the intratumor heterogeneity of non-silent mutations. The results showed that the mediastinal lesion tissue has higher degree of heterogeneity and the lung lesion tissue has relatively low amount of variant heterogeneity in the detected variants. Through pathology and genomics sequencing detection, we initially revealed the genetic differences between mediastinal thymoma and ectopic thymoma, and clonal evolution analysis showed that these two lesions originated from multi-ancestral regions.

Effect of Stereotactic Body Radiation Therapy on Diverse Organ Lesions in Advanced Non-Small Cell Lung Cancer Patients Receiving Immune Checkpoint Inhibitors.

OBJECTIVE: The combination of stereotactic body radiation therapy (SBRT) and immune checkpoint inhibitors (ICIs) is actively being explored in advanced non-small-cell lung cancer (NSCLC) patients. However, little is known about the optimal fractionation and radiotherapy target lesions in this scenario. This study investigated the effect of SBRT on diverse organ lesions and radiotherapy dose fractionation regimens on the prognosis of advanced NSCLC patients receiving ICIs. METHODS: The medical records of advanced NSCLC patients consecutively treated with ICIs and SBRT were retrospectively reviewed at our institution from Dec. 2015 to Sep. 2021. Patients were grouped according to radiation sites. Progression-free survival (PFS) and overall survival (OS) were recorded using the Kaplan-Meier method and compared between different treatment groups using the log-rank (Mantel-Cox) test. RESULTS: A total of 124 advanced NSCLC patients receiving ICIs combined with SBRT were identified in this study. Radiation sites included lung lesions (lung group, n=43), bone metastases (bone group, n=24), and brain metastases (brain group, n=57). Compared with the brain group, the mean PFS (mPFS) in the lung group was significantly prolonged by 13.3 months (8.5 months vs. 21.8 months, HR=0.51, 95%CI: 0.28-0.92, P=0.0195), and that in the bone group prolonged by 9.5 months with a 43% reduction in the risk of disease progression (8.5 months vs. 18.0 months, HR=0.57, 95%CI: 0.29-1.13, P=0.1095). The mPFS in the lung group was prolonged by 3.8 months as compared with that in the bone group. The mean OS (mOS) in the lung and bone groups was longer than that of the brain group, and the risk of death decreased by up to 60% in the lung and bone groups as compared with that of the brain group. When SBRT was concurrently given with ICIs, the mPFS in the lung and brain groups were significantly longer than that of the bone group (29.6 months vs. 16.5 months vs. 12.1 months). When SBRT with 8-12 Gy per fraction was combined with ICIs, the mPFS in the lung group was significantly prolonged as compared with that of the bone and brain groups (25.4 months vs. 15.2 months vs. 12.0 months). Among patients receiving SBRT on lung lesions and brain metastases, the mPFS in the concurrent group was longer than that of the SBRT→ICIs group (29.6 months vs. 11.4 months, P=0.0003 and 12.1 months vs. 8.9 months, P=0.2559). Among patients receiving SBRT with <8 Gy and 8-12 Gy per fraction, the mPFS in the concurrent group was also longer than that of the SBRT→ICIs group (20.1 months vs. 5.3 months, P=0.0033 and 24.0 months vs. 13.4 months, P=0.1311). The disease control rates of the lung, bone, and brain groups were 90.7%, 83.3%, and 70.1%, respectively. CONCLUSION: The study demonstrated that the addition of SBRT on lung lesions versus bone and brain metastases to ICIs improved the prognosis in advanced NSCLC patients. This improvement was related to the sequence of radiotherapy combined with ICIs and the radiotherapy fractionation regimens. Dose fractionation regimens of 8-12 Gy per fraction and lung lesions as radiotherapy targets might be the appropriate choice for advanced NSCLC patients receiving ICIs combined with SBRT.

Endostar plus pembrolizumab combined with a platinum-based dual chemotherapy regime for advanced pulmonary large-cell neuroendocrine carcinoma as a first-line treatment: A case report.

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a rare and highly aggressive cancer with a very poor prognosis. The proper treatment decision and possible prognosis outcome for advanced LCNEC is always an enormous challenge due to its scarcity. Here, we presented a 59-year-old male patient with advanced LCNEC with a non-neuroendocrine immunophenotype who received endostar plus pembrolizumab combined with a platinum-based dual chemotherapy regime as a first-line treatment. At present, the patient's condition is well controlled by medication only and has a progression-free survival of more than 2 years. Adverse effects recorded for this patient during treatment courses include nausea, vomiting, II-III quality bone marrow toxicity, and PD-1 blockage-related hypothyroidism. This case report discussed the feasibility of immunotherapy, anti-angiogenesis agents, and chemotherapy as a first-line therapy in advanced LCNEC.

Activated amino acid response pathway generates apatinib resistance by reprograming glutamine metabolism in non-small-cell lung cancer.

The efficacy of apatinib has been confirmed in the treatment of solid tumors, including non-small-cell lung cancer (NSCLC). However, the direct functional mechanisms of tumor lethality mediated by apatinib and the precise mechanisms of drug resistance are largely unknown. In this study, we demonstrated that apatinib could reprogram glutamine metabolism in human NSCLC via a mechanism involved in amino acid metabolic imbalances. Apatinib repressed the expression of GLS1, the initial and rate-limiting enzyme of glutamine catabolism. However, the broken metabolic balance led to the activation of the amino acid response (AAR) pathway, known as the GCN2/eIF2α/ATF4 pathway. Moreover, activation of ATF4 was responsible for the induction of SLC1A5 and ASNS, which promoted the consumption and metabolization of glutamine. Interestingly, the combination of apatinib and ATF4 silencing abolished glutamine metabolism in NSCLC cells. Moreover, knockdown of ATF4 enhanced the antitumor effect of apatinib both in vitro and in vivo. In summary, this study showed that apatinib could reprogram glutamine metabolism through the activation of the AAR pathway in human NSCLC cells and indicated that targeting ATF4 is a potential therapeutic strategy for relieving apatinib resistance.

Novel germline mutation in lung cancer pedigrees establishes BCAR1 as a human cancer susceptibility gene: a case report.

Background: Lung cancer is the most prevalent malignancy worldwide. Most cases are sporadic and carry somatic mutations in hotspot genes. However, accumulating studies have identified several germline mutations that predispose patients to lung cancer at present. Case Description: In this report, 2 siblings diagnosed with lung squamous cell carcinoma and lung adenocarcinoma were sequenced by whole exome sequencing (WES) and Sanger sequencing. In this context, we reported a novel frameshift germline mutation of breast cancer anti-estrogen resistance protein 1 (BCAR1) in exon 4 (NM_001170717: c.942delinsAATGCCAGGGC), causing a frameshift and introducing a premature stop codon, which was detected in both siblings. Screening across other family members revealed their presence in 2 affected individuals. The BCAR1 gene was previously demonstrated to be associated with lung cancer. The variant detected in this report would impair the regulation and functions of BCAR1 in some extent, thus may promote the tumorigenesis of lung cancer. Conclusions: In conclusion, our findings suggest that BCAR1 is a possible susceptibility gene for lung cancer, and its functional analyses in lung cancer need further investigation. In this study, we first reported a novel causative mechanism of lung cancer: an insertion of 11 bp in BCAR1 gene, which can be helpful in the genetic diagnosis of this disease.

BRD4-IRF1 axis regulates chemoradiotherapy-induced PD-L1 expression and immune evasion in non-small cell lung cancer.

BACKGROUND: Chemoradiotherapy-induced PD-L1 upregulation leads to therapeutic resistance and treatment failure. The PD-1/PD-L1 blocking antibodies sensitize cancers to chemoradiotherapy by blocking extracellular PD-1 and PD-L1 binding without affecting the oncogenic function of intracellular PD-L1. Reversing the chemoradiation-induced PD-L1 expression could provide a new strategy to achieve a greater anti-tumour effect of chemoradiotherapy. Here, we aimed to identify candidate small molecular inhibitors that might boost the anti-tumour immunity of chemoradiotherapy by decreasing treatment-induced PD-L1 expression in non-small cell lung cancer (NSCLC). METHODS: A drug array was used to recognize compounds that can suppress the cisplatin-induced and radiation-induced PD-L1 expression in NSCLC via the flow cytometry-based assay. We examined whether and how targeting bromodomain containing 4 (BRD4) inhibits chemoradiation-induced PD-L1 expression and evaluated the effect of BRD4 inhibition and chemoradiation combination in vivo. RESULTS: BRD4 inhibitors JQ1 and ARV-771 were identified as the most promising drugs both in the cisplatin and radiation screening projects in two NSCLC cell lines. Targeting BRD4 was supposed to block chemoradiotherapy inducible PD-L1 expression by disrupting the recruitment of BRD4-IRF1 complex to PD-L1 promoter. A positive correlation between BRD4 and PD-L1 expression was observed in human NSCLC tissues. Moreover, BRD4 inhibition synergized with chemoradiotherapy and PD-1 blockade to show a robust anti-tumour immunity dependent on CD8+ T cell through limiting chemoradiation-induced tumour cell surface PD-L1 upregulation in vivo. Notably, the BRD4-targeted combinatory treatments did not show increased toxicities. CONCLUSION: The data showed that BRD4-targeted therapy synergized with chemoradiotherapy and anti-PD-1 antibody by boosting anti-tumour immunity in NSCLC.

Early evaluation of subclinical cardiotoxicity in patients with lung cancer receiving immune checkpoint inhibitors by cardiovascular magnetic resonance: a prospective observational study.

Background: Few studies have focused on the subclinical cardiotoxicity of immune checkpoint inhibitors (ICIs) in cancer patients. This study aimed to evaluate the manifestations of subclinical cardiotoxicity of ICI therapy using cardiovascular magnetic resonance (CMR) and to explore whether CMR parameters can help predict cardiotoxicity at the early stage of ICI therapy. Methods: A prospective, longitudinal study was conducted among patients with lung cancer. The patients were planned to undergo serial CMRs before (baseline), 3 weeks after (1st follow-up), and 3 months after (2nd follow-up) the initiation of ICI therapy, respectively. Patients with 3 CMRs were included in the analysis. Serial quantitative measurements based on CMR were compared using one-way repeated measures analysis of variance (RM-ANOVA). On the basis of cancer therapy-related cardiac dysfunction (CTRCD) observed at the second follow-up, patients were categorized into a CTRCD group and a non-CTRCD group. Baseline clinical and CMR parameters and the relative reduction of left ventricular global strain at the second follow-up was compared between the CTRCD group and the non-CTRCD group. Receiver operating characteristic (ROC) analysis was used to identify CTRCD that developed 3 months after ICI therapy. Results: A total of 36 patients with 3 CMRs (60.7±9.2 years old, 77.8% male) were included in the analysis. Left ventricular-global radial strain (LV-GRS) decreased significantly at the second follow-up (37.9%±8.5% vs. 33.1%±1.0%; P=0.014), but left ventricular ejection fraction (LVEF) did not change significantly (51.5%±6.0% vs. 49.2%±6.5%; P>0.05). A total of 7 patients (19.4%) had developed CTRCD by the second follow-up. Baseline clinical and CMR parameters did not differ between the CTRCD group and the non-CTRCD group (P>0.05 for all). In the CTRCD group, the left ventricular-global circumferential strains (LV-GCSs) showed significant reductions at both the first and second follow-up (P=0.008 and 0.035, respectively), but the LVEF only showed a significant reduction at the second follow-up (P<0.001). The relative reduction of LV-GRS at the second follow-up was significantly higher in the CTRCD group than in the non-CTRCD group (29.8%±25.8% vs. 6.8%±20.4%; P=0.036) and was used to predict CTRCD developed at the 3-month timepoint after ICI therapy [area under the curve (AUC) =0.759; P=0.036]. Conclusions: In the early stage of ICI therapy, assessment of myocardial strain can be used to detect subclinical left ventricular systolic dysfunction in patients with lung cancer earlier than LVEF. The relative reduction of LV-GRS can be used to predict CTRCD 3 months after ICI therapy.

NLRP6 is required for cancer-derived exosome-modified macrophage M2 polarization and promotes metastasis in small cell lung cancer.

Metastasis remains the primary cause of small cell lung cancer (SCLC)-related deaths. Growing evidence links tumor metastasis with a pre-metastatic microenvironment characterized by an anti-inflammatory response, immunosuppression, and the presence of tumor-derived exosomes. To clarify the relationships among these factors in SCLC, we analyzed SCLC patient samples as well as a mouse model. Among the infiltrating immune cells, our study focused on the tumor-associated macrophages (TAMs), that are well-known to promote tumor progression and metastasis. We found that high expression of the alternatively activated (M2) TAM marker, CD206+ was associated clinically with a poorer prognosis and metastasis state in patients with SCLC. Moreover, infiltrating macrophages (MØ) were found in the metastatic foci of an SCLC mouse model. Additionally, we observed dominant switching to M2 phenotype, accompanied by increased NLRP6 expression. Since tumor-derived exosomes are the key links between the tumor and its immune microenvironment, we further investigated whether SCLC-derived exosomes contributed to the MØ phenotype switch. Our findings showed for the first time that SCLC-derived exosomes induce the M2 switch via the NLRP6/NF-κB pathway, and thus, promote SCLC metastasis in vitro and in vivo. Collectively, these results indicate a novel mechanism by which SCLC-derived exosomes induce immunosuppression of distant MØ to promote systemic metastasis by activating NLRP6. Here, we highlight the close relationship between the tumor-derived exosomes, inflammasomes and immune microenvironment in SCLC metastasis.

Identification of the Nerve-Cancer Cross-Talk-Related Prognostic Gene Model in Head and Neck Squamous Cell Carcinoma.

The incidence of head and neck squamous cell carcinoma (HNSC) is increasing year by year. The nerve is an important component of the tumor microenvironment, which has a wide range of cross-talk with tumor cells and immune cells, especially in highly innervated organs, such as head and neck cancer and pancreatic cancer. However, the role of cancer-nerve cross-talk-related genes (NCCGs) in HNSC is unclear. In our study, we constructed a prognostic model based on genes with prognostic value in NCCGs. We used Pearson's correlation to analyze the relationship between NCCGs and immune infiltration, microsatellite instability, tumor mutation burden, drug sensitivity, and clinical stage. We used single-cell sequencing data to analyze the expression of genes associated with stage in different cells and explored the possible pathways affected by these genes via gene set enrichment analysis. In the TCGA-HNSC cohort, a total of 23 genes were up- or downregulated compared with normal tissues. GO and KEGG pathway analysis suggested that NCCGs are mainly concentrated in membrane potential regulation, chemical synapse, axon formation, and neuroreceptor-ligand interaction. Ten genes were identified as prognosis genes by Kaplan-Meier plotter and used as candidate genes for LASSO regression. We constructed a seven-gene prognostic model (NTRK1, L1CAM, GRIN3A, CHRNA5, CHRNA6, CHRNB4, CHRND). The model could effectively predict the 1-, 3-, and 5-year survival rates in the TCGA-HNSC cohort, and the effectiveness of the model was verified by external test data. The genes included in the model were significantly correlated with immune infiltration, microsatellite instability, tumor mutation burden, drug sensitivity, and clinical stage. Single-cell sequencing data of HNSC showed that CHRNB4 was mainly expressed in tumor cells, and multiple metabolic pathways were enriched in high CHRNB4 expression tumor cells. In summary, we used comprehensive bioinformatics analysis to construct a prognostic gene model and revealed the potential of NCCGs as therapeutic targets and prognostic biomarkers in HNSC.

Cardiac telocytes inhibit cardiac microvascular endothelial cell apoptosis through exosomal miRNA-21-5p-targeted cdip1 silencing to improve angiogenesis following myocardial infarction.

Promotion of cardiac angiogenesis in ischemic myocardium is a critical strategy for repairing and regenerating the myocardium after myocardial infarction (MI). Currently, effective methods to aid in the survival of endothelial cells, to avoid apoptosis in ischemic myocardium and to achieve long-term cardiac angiogenesis are still being pursued. Here, we investigated whether cardiac telocyte (CT)-endothelial cell communication suppresses apoptosis and promotes the survival of endothelial cells to facilitate cardiac angiogenesis during MI. Methods: CT exosomes were isolated from CT conditioned medium, and their miRNA profile was characterized by small RNA sequencing. A rat model of left anterior descending coronary artery ligation (LAD)-mediated MI was assessed with histology for infarct size and fibrosis, immunostaining for angiogenesis and cell apoptosis and echocardiography to evaluate the therapeutic effects. Cardiac microvascular endothelial cells (CMECs) and the LAD-MI model treated with CT exosomes or CT exosomal miRNA-21-5p in vitro and in vivo were assessed with cellular and molecular techniques to demonstrate the underlying mechanism. Results: CTs exert therapeutic effects on MI via the potent paracrine effects of CT exosomes to facilitate the inhibition of apoptosis and survival of CMECs and promote cardiac angiogenesis. A novel mechanism of CTs is revealed, in which CT-endothelial cell communication suppresses apoptosis and promotes the survival of endothelial cells in the pathophysiological myocardium. CT exosomal miRNA-21-5p targeted and silenced the cell death inducing p53 target 1 (Cdip1) gene and thus down-regulated the activated caspase-3, which then inhibited the apoptosis of recipient endothelial cells under ischemic and hypoxic conditions, facilitating angiogenesis and regeneration following MI. Conclusions: The present study is the first to show that CTs inhibit cardiac microvascular endothelial cell apoptosis through exosomal miRNA-21-5p-targeted Cdip1 silencing to improve angiogenesis in myocardial infarction. It is believed that these novel findings and the discovery of cellular and molecular mechanisms will provide new opportunities to tailor novel cardiac cell therapies and cell-free therapies for the functional and structural regeneration of the injured myocardium.