Hydroxycitric Acid Alleviated Lung Ischemia-Reperfusion Injury by Inhibiting Oxidative Stress and Ferroptosis through the Hif-1α Pathway.

Lung ischemia-reperfusion injury (LIRI) is a prevalent occurrence in various pulmonary diseases and surgical procedures, including lung resections and transplantation. LIRI can result in systemic hypoxemia and multi-organ failure. Hydroxycitric acid (HCA), the primary acid present in the peel of Garcinia cambogia, exhibits anti-inflammatory, antioxidant, and anticancer properties. However, the effects of HCA on LIRI remain unknown. To investigate the impact of HCA on LIRI in mice, the mice were randomly divided into four groups: the control group, the I/R model group, and the I/R + low- or high-dose HCA groups. Human umbilical vein endothelial cells (HUVECs) were subjected to hypoxia for 12 h followed by reoxygenation for 6 h to simulate in vitro LIRI. The results demonstrated that administration of HCA effectively attenuated lung injury, inflammation, and edema induced by ischemia reperfusion. Moreover, HCA treatment significantly reduced malondialdehyde (MDA) and reactive oxygen species (ROS) levels while decreasing iron content and increasing superoxide dismutase (SOD) levels after ischemia-reperfusion insult. Mechanistically, HCA administration significantly inhibited Hif-1α and HO-1 upregulation both in vivo and in vitro. We found that HCA could also alleviate endothelial barrier damage in H/R-induced HUVECs in a concentration-dependent manner. In addition, overexpression of Hif-1α counteracted HCA-mediated inhibition of H/R-induced endothelial cell ferroptosis. In summary, these results indicate that HCA alleviated LIRI by inhibiting oxidative stress and ferroptosis through the Hif-1α pathway.

Systematic analysis of histone acetylation regulators across human cancers.

BACKGROUND: Histone acetylation (HA) is an important and common epigenetic pathway, which could be hijacked by tumor cells during carcinogenesis and cancer progression. However, the important role of HA across human cancers remains elusive. METHODS: In this study, we performed a comprehensive analysis at multiple levels, aiming to systematically describe the molecular characteristics and clinical relevance of HA regulators in more than 10000 tumor samples representing 33 cancer types. RESULTS: We found a highly heterogeneous genetic alteration landscape of HA regulators across different human cancer types. CNV alteration may be one of the major mechanisms leading to the expression perturbations in HA regulators. Furthermore, expression perturbations of HA regulators correlated with the activity of multiple hallmark oncogenic pathways. HA regulators were found to be potentially useful for the prognostic stratification of kidney renal clear cell carcinoma (KIRC). Additionally, we identified HDAC3 as a potential oncogene in lung adenocarcinoma (LUAD). CONCLUSION: Overall, our results highlights the importance of HA regulators in cancer development, which may contribute to the development of clinical strategies for cancer treatment.

Eriocitrin attenuates sepsis-induced acute lung injury in mice by regulating MKP1/MAPK pathway mediated-glycolysis.

Metabolic reprogramming has been shown to aggravate sepsis-induced acute lung injury. In particular, enhanced glycolysis is closely associated with inflammation and oxidative stress. Eriocitrin (ERI) is a natural flavonoid found in citrus fruit that exhibits various pharmacological activities, with antioxidant, anti-inflammatory, anti-diabetic, and anti-tumor properties. However, the role of ERI in lung injury is not well understood. We established a septic mouse model of acute lung injury (ALI) using lipopolysaccharide (LPS) for induction. Primary peritoneal macrophages were isolated to verify the relevant molecular mechanism. Tissues were assessed for lung pathology, pro-inflammatory cytokines, markers of oxidative stress, and protein and mRNA expression levels. In vivo experiments showed that ERI effectively alleviated LPS-induced pathological injury, suppress the inflammatory response (TNF-α, IL-1ß, IL-6 levels) and decreased oxidative stress (MDA, ROS) in murine lung tissue. In vitro, ERI increased the resistance of LPS-treated cells to excessive inflammation and oxidative stress by inhibiting the enhancement of glycolysis (indicated by expression levels of HIF-1α, HK2, LDHA, PFKFB3, and PKM2). Specifically, the beneficial effects of ERI following LPS-induced lung injury occurred through promoting the expression of MKP1, which mediates the inactivation of the MAPK pathway to inhibit enhanced glycolysis. These results demonstrate that ERI has a protective effect on sepsis-induced ALI by regulating MKP1/MAPK pathway mediated-glycolysis. Hence, ERI is a promising candidate against ALI via inhibiting glycolysis.

Single-cell RNA sequencing analysis revealed cellular and molecular immune profiles in lung squamous cell carcinoma.

Although breakthroughs have been made in the treatment of non-small cell lung cancer, there are only a few choices for advanced-stage or recurrent lung squamous cell carcinoma (LUSC) patients. In our study, we identified 7 major cell types in thedepicted the immunolandscape of LUSC microenvironment using single-cell RNA sequencing. We found that an immunosuppressive receptor, T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), was highly expressed by regulatory T cells (Tregs) and exhausted CD8+T cells, suggesting that upregulation of TIGIT might promote an immunosuppressive microenvironment and inhibit the cytotoxic ability of CD8+T cells. We also identified tumor-associated neutrophil (TAN), characterized by CXCR2, CSF3R and CXCL8, in the tumor region, and TANs upregulated the expression of interleukin 1 receptor antagonist (IL1RN) which suggested that TAN might exert an immunosuppressive role via expressing IL1RN. Furthermore, the number of SPP1+ macrophages(SPP1+M) significantly increased in tumor microenvirnment, which was correlated with the poor survival of patients. Additionally, regulatory networks based on SPP1+M revealed that the disparities of several ligand-receptor pairs existed between tumor and normal tissues. Among these pairs, SPP1-CD44 showed the most interactions between SPP1+M and other cell types. Our results provided deep insight into the immune landscape of LUSC and an essential resource for drug discovery in the future.

Mitophagy: A novel perspective for insighting into cancer and cancer treatment.

BACKGROUND: Mitophagy refers to the selective self-elimination of mitochondria under damaged or certain developmental conditions. As an important regulatory mechanism to remove damaged mitochondria and maintain the internal and external cellular balance, mitophagy plays pivotal roles in carcinogenesis and progression as well as treatment. MATERIALS AND METHODS: Here, we combined data from recent years to comprehensively describe the regulatory mechanisms of mitophagy and its multifaceted significance in cancer, and discusse the potential of targeted mitophagy as a cancer treatment strategy. RESULTS: The molecular mechanisms regulating mitophagy are complex, diverse, and cross-talk. Inducing or blocking mitophagy has the same or completely different effects in different cancer contexts. Mitophagy plays an indispensable role in regulating cancer metabolic reprogramming, cell stemness, and chemotherapy resistance for better adaptation to tumor microenvironment. In cancer cell biology, mitophagy is considered to be a double-edged sword. And to fully understand the role of mitophagy in cancer development can provide new targets for cancer treatment in clinical practice. CONCLUSIONS: This review synthesizes a large body of data to comprehensively describe the molecular mechanisms of mitophagy and its multidimensional significance in cancer and cancer treatment, which will undoubtedly deepen the understanding of mitophagy.

Identification of cuproptosis-related subtypes in lung adenocarcinoma and its potential significance.

Cuproptosis is a novel and unique cell death mode that has attracted significant interest in recent years. Little is currently known about whether cuproptosis-related genes (CRGs) are associated with the pathophysiology and survival of patients with lung adenocarcinoma (LUAD). The present study sought to characterize the transcriptional and genetic alteration of CRGs in LUAD and its potential significance in the tumor microenvironment and predicting the prognosis of LUAD. The secondary eventual aim was to study the role of CRGs in predicting immunotherapy response and its clinical value combined with the TNM stage. We found that several CRGs, including FDX1, DLD, SLC31A1, and MTF1, were enriched in macrophages in our single-cell RNA-seq data. Three distinct molecular subtypes were identified and correlated with clinicopathological characteristics, prognosis, biological pathways, and tumor microenvironment (TME) in LUAD. We developed a cuproptosis-related gene score (CRG_score) and validated it in three independent cohorts and clinical subtypes. The low CRG_score group, characterized by a greater immune score, immunophenoscore (IPS), lower tumor immune dysfunction and exclusion (TIDE) score, and T-cell dysfunction score, had a better prognosis, suggesting that the low CRG_score group responded more favorably to immunotherapy, which was validated in the anti-PD-1/L1 immunotherapy cohort (IMvigor210). In contrast, the high CRG_score group was more sensitive to targeted therapy and chemotherapy, with a higher cancer stem cell (CSC) index and lower half-maximal inhibitory concentration (IC50) for many drugs. Given the established crosstalk between CRG_score and tumor TNM stage, we developed an accurate nomogram for clinical application of the CRG_score. Taken together, our rigorous and comprehensive examination of CRGs in LUAD identified their potential functions in TME, clinicopathological characteristics, drug sensitivity, and prognosis. These findings improve the current understanding of cuproptosis in LUAD, paving the way for more accurate prognosis assessment and tailored treatment for this patient population.

Squamous cell carcinoma predicts worse prognosis than adenocarcinoma in stage IA lung cancer patients: A population-based propensity score matching analysis.

Background: Although numerous studies have reported the association between histological types and the prognosis of IA non-small-cell lung cancer (NSCLC) patients, few studies have deeply investigated the impact of pathology on the outcome of NSCLC patients. In this study, we comprehensively explored whether the type of histology influenced the outcome of IA-stage NSCLC patients. Methods: The study population was obtained from the Surveillance, Epidemiology, and End Results (SEER) program, which is supported by the National Cancer Institute of the United States. To avoid potential bias, the method of propensity score matching (PSM) was used to obtain a balanced cohort for further analysis. Results: The results from univariate and multivariate regression models showed that lung squamous cell carcinoma (LSQCC) patients were at a significantly greater risk of undergoing shorter overall survival (OS) and lung cancer-specific survival (LCSS). After PSM analysis, LSQCC was still closely associated with a reduction in OS and LCSS. All of these suggested that the histological type was an independent prognostic factor for OS and LCSS. Conclusion: Our study demonstrated that squamous cell carcinoma predicted worse OS and LCSS in IA-stage NSCLC patients compared with lung adenocarcinoma (LUAD). We suggest that the outcomes of LSQCC and LUAD are very different and that the two histological types should be differently analyzed.

Comprehensive analysis reveals the potential value of inflammatory response genes in the prognosis, immunity, and drug sensitivity of lung adenocarcinoma.

BACKGROUND: Although the relationship between inflammatory response and tumor has been gradually recognized, the potential implications of of inflammatory response genes in lung adenocarcinoma (LUAD) remains poorly investigated. METHODS: RNA sequencing and clinical data were obtained from multiple independent datasets (GSE29013, GSE30219, GSE31210, GSE37745, GSE42127, GSE50081, GSE68465, GSE72094, TCGA and GTEx). Unsupervised clustering analysis was used to identify different tumor subtypes, and LASSO and Cox regression analysis were applied to construct a novel scoring tool. We employed multiple algorithms (ssGSEA, CIBERSORT, MCP counter, and ESTIMATE) to better characterize the LUAD tumor microenvironment (TME) and immune landscapes. GSVA and Metascape analysis were performed to investigate the biological processes and pathway activity. Furthermore, 'pRRophetic' R package was used to evaluate the half inhibitory concentration (IC50) of each sample to infer drug sensitivity. RESULTS: We identified three distinct tumor subtypes, which were related to different clinical outcomes, biological pathways, and immune characteristics. A scoring tool called inflammatory response gene score (IRGS) was established and well validated in multiple independent cohorts, which could well divide patients into two subgroups with significantly different prognosis. High IRGS patients, characterized by increased genomic variants and mutation burden, presented a worse prognosis, and might show a more favorable response to immunotherapy and chemotherapy. Additionally, based on the cross-talk between TNM stage, IRGS and patients clinical outcomes, we redefined the LUAD stage, which was called 'IRGS-Stage'. The novel staging system could distinguish patients with different prognosis, with better predictive ability than the conventional TNM staging. CONCLUSIONS: Inflammatory response genes present important potential value in the prognosis, immunity and drug sensitivity of LUAD. The proposed IRGS and IRGS-Stage may be promising biomarkers for estimating clinical outcomes in LUAD patients.

Survival after wedge resection versus lobectomy for stage IA second primary NSCLC with previous lung cancer-directed surgery.

Background: The surgical procedure for early-stage second primary non-small cell lung cancer (SP-NSCLC) remains controversial, especially for patients with previous lung cancer-directed surgery. This study aims to compare the survival after wedge resection and lobectomy for these patients. Methods: Stage IA SP-NSCLC patients with clear clinical information were searched from the Surveillance, Epidemiology, and End Results (SEER) database. The Cox proportional hazard model, the competing risk model, and the Kaplan-Meier survival curve were used to describe the survival difference between wedge resection and lobectomy. A 1:1 propensity score matching (PSM) method was also performed to reduce the potential impact of confounding factors between the two groups. Results: Of the 320 eligible stage IA SP-NSCLC patients included in this study, 238 (74.4%) patients underwent wedge resection and 82 (25.6%) patients received lobectomy. The 5-year overall survival (OS) was 61.3% with wedge resection and was 66.1% with lobectomy. Both before and after PSM, wedge resection showed similar OS and lung cancer-specific mortality as lobectomy in the entire cohort. Additionally, in all subgroup analyses, wedge resection demonstrated equivalent survival to lobectomy. However, in the female, sublobectomy for the first primary lung cancer, and interval ≤ 24 months subgroups, wedge resection displayed a higher lung cancer-specific mortality than lobectomy (fine-gray test, all p < 0.05). Conclusion: Overall, wedge resection is comparable to lobectomy in OS for stage IA SP-NSCLC patients with previous lung cancer-directed surgery. Therefore, we believe that wedge resection may be sufficient for these patients, although, in some cases, wedge resection has a higher lung cancer-specific mortality rate than lobectomy.

Comprehensive Analysis of Programmed Cell Death Signature in the Prognosis, Tumor Microenvironment and Drug Sensitivity in Lung Adenocarcinoma.

Programmed cell death (PCD) is a process that regulates the homeostasis of cells in the body, and it plays an important role in tumor immunity. However, the expression profile and clinical characteristics of PCD-related genes remain unclear. In this study, we comprehensively analysed the PCD genes with the tumor microenvironment (TME), drug sensitivity, immunothearapy response, and evaluated their prognostic value through systematic bioinformatics methods.We identified 125 PCD-related regulatory factors, which were expressed differently in lung adenocarcinoma (LUAD) and normal lung tissues. 32 PCD related prognostic genes associated with LUAD were identified by univariate Cox analysis. 23 PCD-related gene signature was constructed, and all LUAD patients in the Cancer Genome Atlas (TCGA) dataset were stratified as low-risk or high-risk groups according to the risk score. This signature had a powerful prognostic value, which was validated in three independent data sets and clinical subtypes. Additionally, it has unique properties in TME. Further analysis showed that different risk groups have different immune cell infiltration, immune inflammation profile, immune pathways, and immune subtypes. In addition, the low-risk group had a better immunotherapy response with higher levels of multiple immune checkpoints and lower Tumor immune dysfunction and exclusion (TIDE) score, while the high-risk group was sensitive to multiple chemotherapeutic drugs because of its lower IC50. In short, this is the first model to predict the prognosis and immunological status of LUAD patients based on PCD-related genes. It may be used as a predictor of immunotherapy response to achieve customized treatment of LUAD.

Identification of an inflammatory response signature associated with prognostic stratification and drug sensitivity in lung adenocarcinoma.

Increasing evidence has confirmed the close connection between inflammatory response and tumorigenesis. However, the relationship between inflammatory response genes (IRGs) and the prognosis of lung adenocarcinoma (LUAD) as well as the response to drug therapy remains poorly investigated. Here, we comprehensively analyzed IRGs RNA expression profiling and clinical features of over 2000 LUAD patients from 12 public datasets. The Cox regression method and LASSO analysis were combined to develop a novel IRG signature for risk stratification and drug efficacy prediction in LUAD patients. Enriched pathways, tumor microenvironment (TME), genomic and somatic mutation landscape in different subgroups were evaluated and compared with each other. This established IRG signature including 11 IRGs (ADM, GPC3, IL7R, NMI, NMURI, PSEN1, PTPRE, PVR, SEMA4D, SERPINE1, SPHK1), could well categorize patients into significantly different prognostic subgroups, and have better predictive in independently assessing survival as compared to a single clinical factor. High IRG scores (IRGS) patients might benefit more from immunotherapy and chemotherapy. Comprehensive analysis uncovered significant differences in enriched pathways, TME, genomic and somatic mutation landscape between the two subgroups. Additionally, integrating the IRGS and TNM stage, a reliable prognostic nomogram was developed to optimize survival prediction, and validated in an independent external dataset for clinical application. Take together, the proposed IRG signature in this study is a promising biomarker for risk stratification and drug efficacy prediction in LUAD patients. This study may be meaningful for explaining the responses of clinical therapeutic drugs and providing new strategies for administrating sufferer of LUAD.

Comprehensive molecular analysis of a four-pyroptosis-gene signature with prognosis and immune landscape in lung adenocarcinoma.

Pyroptosis plays an important role in tumor immunity. However, the biological behavior and prognostic significance of pyroptosis remain unclear. We identified 41 pyroptosis regulators differently expressed in lung adenocarcinoma (LUAD). All cases of LUAD can be classified into two molecular subtypes using unsupervised clustering algorithm. Using multiple analyses, a four-pyroptosis-gene signature was constructed, and all LUAD patients were categorized as low-risk or high-risk with a longer overall survival (OS) time in the low-risk group(P < 0.001). This signature had power prognosis and stratification which was validated by six independent datasets and clinical subtypes. Besides, this signature showed distinct clinical outcomes, immune landscapes in different risk groups. Moreover, the low-risk group had a higher response against immunotherapy with a lower TIDE score. Importantly, this signature surpassed other biomarkers (TIDE, TMB, PD-L1) in predicting prognosis. Overall, the current study might help with precise prognostic prediction and crucial treatment strategies, eventually promoting tailored therapy for LUAD patients.

Clinical Significance and Immunologic Landscape of a Five-IL(R)-Based Signature in Lung Adenocarcinoma.

Interleukins (ILs) and interleukin receptors (ILRs) play important role in the antitumor immune response. However, the expression signature and clinical characteristics of the IL(R) family in lung adenocarcinoma (LUAD) remains unclear. The main purpose of this study was to explore the expression profile of IL(R) family genes and construct an IL(R)-based prognostic signature in LUAD. Five public datasets of 1,312 patients with LUAD were enrolled in this study. Samples from The Cancer Genome Atlas (TCGA) were used as the training set, and samples from the other four cohorts extracted from Gene Expression Omnibus (GEO) database were used as the validation set. Additionally, the profile of IL(R) family signature was explored, and the association between this signature and immunotherapy response was also analyzed. Meanwhile, the prognostic value was compared between this IL(R)-based signature and different immunotherapy markers. A signature based on five identified IL(R)s (IL7R, IL5RA, IL20RB, IL11, IL22RA1) was constructed using the TCGA dataset through univariate/multivariable Cox proportional hazards regression and least absolute shrinkage and selection operator (LASSO) Cox analysis. These cases with LUAD were stratified into high- and low-risk group according to the risk score. This signature showed a strong prognostic ability, which was verified by the five independent cohorts and clinical subtypes. The IL(R)-based models presented unique characteristics in terms of immune cell infiltration and immune inflammation profile in tumor microenvironment (TME). Biological pathway analysis confirmed that high-risk patients showed significant T- and B-cell immunosuppression and rapid tumor cell proliferation. More importantly, we researched the relationship between this IL(R)-based signature and immune checkpoints, tumor mutation burden (TMB), tumor purity and ploidy, and tumor immune dysfunction and exclusion (TIDE) score, which confirmed that this signature gave the best prognostic value. We first provided a robust prognostic IL(R)-based signature, which had the potential as a predictor for immunotherapy response to realize individualized treatment of LUAD.

Reconstruction of the esophagus of patients with middle thoracic esophageal carcinoma using the remnant stomach following Billroth II gastrectomy.

It seems impossible to reconstruct the esophagus of patients with middle thoracic esophageal carcinoma with a history of distal gastrectomy using the remnant stomach. Although surgeons have made multiple efforts to reconstruct the esophagus using the remnant stomach, it can only be successfully used in cases of lower thoracic esophageal cancer. Additionally, the surgery is more complex than traditional esophagogastrostomy due to challenges including mobilization of the remnant stomach with the spleen and transposition of the pancreatic tail into the left hemithorax. Our operation proved that the remnant stomach, which we named as the completely mobilized remnant stomach after dissection of the feeding vessels, remained viable. We successfully integrated the completely mobilized remnant stomach in the reconstruction of the lower thoracic esophageal tract and then integrated it in Ivor Lewis esophagogastrostomy. We describe this new alternative surgical technique for the treatment of middle thoracic esophageal carcinoma in patients with a history of distal gastrectomy in this study. Clinical data of 23 patients from 2008 to 2019 were retrospectively analyzed. All patients underwent the Ivor Lewis procedure. All remaining vessels of the remnant stomach were dissected at their origins, and Roux-en-Y reconstruction or Braun anastomosis was performed. After esophagectomy during right thoracotomy, anastomosis of the remnant stomach and esophagus was performed. Two-field lymph node dissections were performed. There was no case of necrosis of the remnant stomach or of perioperative death. Serious complications included anastomotic leak in three cases, afferent-efferent loop syndrome in one, and anastomotic stricture in two. Application of the completely mobilized remnant stomach in Ivor Lewis esophagogastrostomy is feasible, and the surgical procedure is similar to that of normal esophagogastrostomy.

Autophagy decreases alveolar epithelial cell injury by regulating the release of inflammatory mediators.

To research the impact of autophagy on alveolar epithelial cell inflammation and its possible mechanism in the early stages of hypoxia, we established a cell hypoxia-reoxygenation model and orthotopic left lung ischemia-reperfusion model. Rat alveolar epithelial cells stably expressing GFP-LC3 were treated with an autophagy inhibitor (3-MA) or an autophagy promoter (rapamycin), followed by hypoxia-reoxygenation treatment for 2, 4, and 6 hr in vitro. In vivo, 20 male Sprague Dawley rats were randomly divided into four groups (model group: No blocking of the hilum in the left lung; control group: Blocking of the hilum in the left lung for 1 hr with dimethyl sulfoxide lavage; 3-MA group: Blocking of the hilum in the left lung for 1 hr with 100 ml/kg of 3-MA (5 µmol/L) solution lavage; and rapamycin group: Blocking of the hilum in the left lung for 1 hr with 100 ml/kg of rapamycin (250 nmol/L) solution lavage) to establish an orthotopic left lung ischemia model. This study demonstrated that rapamycin significantly suppressed the nuclear factor kappa B signaling pathway and limited the expression of proinflammatory factors. A contrary result was found after the 3-MA pretreatment. These findings indicate that autophagy reduces ischemia-reperfusion injury by repressing inflammatory signaling pathways in the early stages of hypoxia in vitro and in vivo. Autophagy could be a new protective method for application in lung ischemia-reperfusion injury.

Fucosterol exerts antiproliferative effects on human lung cancer cells by inducing apoptosis, cell cycle arrest and targeting of Raf/MEK/ERK signalling pathway.

BACKGROUND: Phytochemicals have attained tremendous attention as the chemo-preventive and chemotheruptic agents. Fucosterol is a phytosterol that in prevalently found in marine algae and many other plant species. Previous studies have indicated the potential of fucosterol as an anticancer agent. However, the information on the anticancer activity of fucosterol against lung cancer as well as several other types of cancers is scantly. PURPOSE: The present study was designed to investigate the anticancer activity of fucosterol against a panel of lung cancer cell lines. METHODS: MTT and colony formation assays were used to determine the cell viability. DAPI and annexin V/PI staining assays were used for the detection of apoptosis. Cell cycle analysis was performed by flow cytometery. Boyden chamber assay was used to monitor cell migration and western blot analysis was used to determine the protein expression. In vivo evaluation was carried out in xenografted mice models. RESULTS: The results indicated that fucosterol inhibits the growth of the lung cancer cell lines. However, the anticancer effects were more profound against the A549 and SK-LU-1 cancer cells (IC50, 15 µM). In contrast, the anticancer effects of fucosterol on the non-cancerous lung cell lines were minimal. Further investigation revealed that the anticancer effects of fucosterol on the A549 and SK-LU-1 cells are due to the induction of apoptosis. Fucosterol significantly enhanced the expression of Bax and cleaved caspase-3 which was concomitant with decline in the expression of Bcl-2. Fucosterol also triggered G2/M cell cycle arrest of the A549 and SK-LU-1 cells which was associated with decrease in the expression of Cdc2, Cyclin A, Cyclin B1 and upregulation of the negative regulators of cell cycle progression (p21Cip1, and p27Kip1). Moreover, fucosterol could also inhibit the invasion of A549 and SK-LU-1 cells. Finally fucosterol could also inhibit the growth of xenografted tumours in mice. CONCLUSION: Taken together, fucosterol inhibits the growth of lung cancer cells and may prove to be a lead molecule for the treatment of lung cancer.

Autophagy decreases alveolar macrophage apoptosis by attenuating endoplasmic reticulum stress and oxidative stress.

To study the impact of autophagy on alveolar macrophage apoptosis and its mechanism in the early stages of hypoxia, we established a cell hypoxia-reoxygenation model and orthotopic left lung ischemia-reperfusion model. Rat alveolar macrophages stably expressing RFP-LC3 were treated with autophagy inhibitor (3-methyladenine, 3-MA) or autophagy promoter (rapamycin), followed by hypoxia-reoxygenation treatment 2 h, 4 h or 6 h later. Twenty Sprague-Dawley male rats were randomly divided into four different groups: no blocking of left lung hilum (model group), left lung hilum blocked for 1h with DMSO lavage (control group), left lung hilum blocked for 1 h with 100 ml/kg 3-MA (5 µmol/L) lavage (3-MA group), and left lung hilum blocked for 1 h with 100 ml/kg rapamycin (250 nmol/L) lavage (rapamycin group). Rapamycin decreased the unfolded protein response, which reduced endoplasmic reticulum stress-mediated apoptosis in the presence of oxygen deficiency. Rapamycin increased superoxide dismutase activities and decreased malondialdehyde levels, whereas 3-MA decreased superoxide dismutase activities and increased malondialdehyde levels. Thus, autophagy decreases alveolar macrophage apoptosis by attenuating endoplasmic reticulum stress and oxidative stress in the early stage of hypoxia in vitro and in vivo. This could represent a new approach to protecting against lung ischemia-reperfusion injury.

Regulatory mechanisms of microRNAs in lung cancer stem cells.

Increasing evidence suggests that cancer stem cells (CSCs) are a key occurrence in the process of many human cancers. Lung cancer is the most common aggressive malignancy and cause of cancer death worldwide. The research on lung cancer stem cells has been highlighted for many years. Lung CSCs seem to play a major role in lung cancer metastasis, drug resistance and tumour-self-renewal. MicroRNAs (miRNAs), a class of newly emerging small noncoding RNAs that act as post-transcriptional regulators of gene expression, have been demonstrated to serve as a vital player in fine-tuning a number of biological activities ranging from embryogenesis to programmed cell death as well as tumourigenesis. In recent years, several miRNAs have been highlighted to be specifically expressed in CSCs. The miRNA profile of CSCs is remarkably different from non-stem cancer cells. As such, many miRNAs have been shown to regulate self-renewal and differentiation properties of CSCs. In this review, we present the latest findings on miRNAs that regulate the tumour microenvironment of lung CSCs with the goal to prompt the development of novel therapeutic strategies for patients with lung cancer.

Associations between autophagy, the ubiquitin-proteasome system and endoplasmic reticulum stress in hypoxia-deoxygenation or ischemia-reperfusion.

The activation of autophagy has been demonstrated to exert protective roles during hypoxia-reoxygenation (H/R)-induced brain injuries. This study aimed to investigate whether and how preconditioning with a proteasome inhibitor (MG-132), a proteasome promoter (Adriamycin, ADM), an autophagy inhibitor (3-methyladenine, 3-MA) and an autophagy promoter (Rapamycin, Rap) affected endoplasmic reticulum stress (ERS), the ubiquitin-proteasome system (UPS), autophagy, inflammation and apoptosis. Ubiquitin protein and 26S proteasome activity levels were decreased by MG-132 pretreatment but increased by ADM pretreatment at 2h, 4h and 6h following H/R treatment. MG-132 pretreatment led to the increased expression of autophagy-related genes, ER stress-associated genes and IκB but decreased the expression levels of NF-κB and caspase-3. ADM pretreatment led to the decreased expression of autophagy-related genes, ERS-associated genes and IκB but increased the expression of NF-κB and caspase-3. Pretreatment with 3-MA reduced the expression of autophagy-related genes, autophagy and UPS co-related genes, as well as apoptosis-related although the latter was increased by Rap pretreatment at 2h, 4h and 6h following H/R treatment. In vivo, pretreatment of rats with ADM, MG-132, 3-MA or Rap followed by ischemia-reperfusion (I/R) treatment resulted in similar changes. Proteasome inhibition preconditioning strengthened autophagy and ER stress but decreased apoptosis and inflammation. Autophagy promotion preconditioning exhibited similar changes. The combination of a proteasome inhibitor and an autophagy promoter might represent a new possible therapy to treat H/R or I/R injury-related diseases.