Prognostic and clinicopathological significance of Beclin-1 in non-small-cell lung cancer: a meta-analysis

Global research and emerging trends in autophagy in lung cancer: a bibliometric and visualized study from 2013 to 2022

Purpose: To highlight the knowledge structure and evolutionary trends in research on autophagy in lung cancer. Methods: Research publications on autophagy in lung cancer were retrieved from the Web of Science Core Collection database. VOSviewer and CiteSpace data analysis software were used for the bibliometric and visualization analysis of countries, institutions, authors, journals, and keywords related to this field. Results: From 2013 to 2022, research on autophagy in lung cancer developed rapidly, showing rising trends in annual publications and citations. China (1,986 papers; 48,913 citations), Shandong University (77 publications; 1,460 citations), and Wei Zhang (20 publications; 342 citations) were the most productive and influential country, institution, and author, respectively. The journal with the most publications and citations on autophagy in lung cancer was the International Journal of Molecular Sciences (93 publications; 3,948 citations). An analysis of keyword co-occurrence showed that related research topics were divided into five clusters: 1) Mechanisms influencing autophagy in lung cancer and the role of autophagy in lung cancer; 2) Effect of autophagy on the biological behavior of lung cancer; 3) Regulatory mechanisms of 2 cell death processes: autophagy and apoptosis in lung cancer cells; 4) Role of autophagy in lung cancer treatment and drug resistance; and 5) Role of autophagy-related genes in the occurrence and development of lung cancer. Cell proliferation, migration, epithelial-mesenchymal transition, and tumor microenvironment were the latest high-frequency keywords that represented promising future research directions. Conclusion: This is the first comprehensive study describing the knowledge structure and emerging frontiers of research on autophagy in lung cancer from 2013 to 2022 by means of a bibliometric analysis. The study points to promising future research directions focusing on in-depth autophagy mechanisms, clinical applications, and potential therapeutic strategies, providing a valuable reference for researchers in the field. Systematic Review Registration: [https://systematicreview.gov/], identifier [registration number].

Autophagy and nuclear morphometry are associated with histopathologic features in esophageal squamous cell carcinoma

Less than 15% of patients with esophageal squamous cell carcinoma (ESCC) survive 5 years after diagnosis. A better understanding of the biology of these tumors and the development of clinical biomarkers is needed. Autophagy is a physiological mechanism involved in the turnover of cellular components that plays a key role in cancer. This study evaluated the differential levels of three key regulators of autophagy (SQSTM1, MAP1LC3B, and BECN1) in patients with ESCC, associating autophagy with histopathologic features, including the grade of differentiation, mitotic rate, inflammation score, and the intensity of tumor-infiltrating lymphocytes. Nuclear morphometry of the tumor parenchyma was also assessed, associating it with autophagy and histopathology. All three markers significantly increased in patients with ESCC compared to the control group. Based on the mean expression of each protein in the control group, 57% of patients with ESCC had high levels of all three markers compared to control patients (14%). The most frequent profiles found in ESCC were BECNhigh/MAP1LC3high and BECNhigh/SQSTM1high. According to the TCGA database, we found that the main autophagy genes were upregulated in ESCC. Moreover, high levels of autophagy markers were associated with a poor prognosis. Considering nuclear morphometry, ESCC samples showed a significant reduction in nuclear area, which was strongly negatively correlated with autophagy. Finally, the percentage of normal nuclei was associated with tumor differentiation, while poorly differentiated tumors showed lower SQSTM1 levels. ESCC progression may involve increased autophagy and changes in nuclear structure, associated with clinically relevant histopathological features. KEY MESSAGES: Autophagy markers are co-increased in primary ESCC. Autophagy negatively correlates with nuclear morphometry in ESCC parenchyma. Autophagy and nuclear morphometry are associated with histopathological features. Autophagy is increased in ESCC-TCGA database and associated with poor prognosis.

Prognostic value of Beclin 1, EGFR and ALK in non-squamous non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the most malignant tumors. The study was carried out to investigate the prognostic value of Beclin 1, EGFR and ALK for this cancer. Patients diagnosed with non-squamous NSCLC and admitted to our hospital from January 2011 to September 2016 were analyzed. Expression of Beclin 1 and mutation of EGFR and ALK were assessed using polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH) and analyzed for their relationship with demographic and clinical characteristics of the patients. Multivariate Cox regression models were applied to analyze the risk factors associated with survival and receiver response curves (ROC) were plotted to determine the prognostic value of Beclin 1, EGFR and ALK for patients with non-squamous NSCLC. Compared with adjacent normal tissue, Beclin 1 expression was elevated in the cancer tissue significantly; assessments of EGFR and ALK mutations showed that out of the 480 patients, 233 (48.5%) and 75 (12.6%) patients had EGFR and ALK mutations. Univariate analysis revealed that Beclin 1 level, EGFR and ALK mutations were associated with lymph node metastasis, TNM stage, tumor differentiation and prognosis, but not with gender, age and smoking status. The Kaplan-Meier survival analysis indicated that low Beclin 1 expression and positive EGFR and ALK rearrangements were associated with higher survival rate and longer progress-free survival (PFS). Multivariate Cox regression analysis showed that Beclin 1, EGFR, ALK mutations, tumor differentiation grade, TNM stage and lymph node metastasis were independently associated with PFS. ROC analysis showed that Beclin 1, EGFR and ALK were significant predictors for PFS; the areas under curve (AUC) for Beclin 1, EGFR and ALK were 0.812 (P = 0.018, cut-off value: 1.2), 0.781 (P = 0.011, cut-off value: 15%) and 0.722 (P = 0.010, cut-off value: 11%), respectively, suggesting that they have significant prognostic value for lung cancer patients. Our data indicate that Beclin 1, EGFR and ALK genes are associated with the prognosis of patients with non-squamous NSCLC. High Beclin 1 expression and negative EGFR and ALK mutations predict a poor prognosis with PFS.

Autophagy regulation by RNA alternative splicing and implications in human diseases

Autophagy and RNA alternative splicing are two evolutionarily conserved processes involved in overlapping physiological and pathological processes. However, the extent of functional connection is not well defined. Here, we consider the role for alternative splicing and generation of autophagy-related gene isoforms in the regulation of autophagy in recent work. The impact of changes to the RNA alternative splicing machinery and production of alternative spliced isoforms on autophagy are reviewed with particular focus on disease relevance. The use of drugs targeting both alternative splicing and autophagy as well as the selective regulation of single autophagy-related protein isoforms, are considered as therapeutic strategies.

Both alternative splicing and autophagy are core cell biological processes, but where they intersect has received little attention. Here, the authors reflect on recent connections identified between these pathways and consider their impact on human disease.

Recent Advances of Autophagy in Non-Small Cell Lung Cancer: From Basic Mechanisms to Clinical Application

Lung cancer is characterized by the most common oncological disease and leading cause of cancer death worldwide, of which a group of subtypes known as non-small cell lung cancer (NSCLC) accounts for approximately 85%. In the past few decades, important progression in the therapies of NSCLC has enhanced our understanding of the biology and progression mechanisms of tumor. The application of immunotherapy and small molecule tyrosine kinase inhibitors has brought significant clinical benefits in certain patients. However, early metastasis and the emergence of resistance to antitumor therapy have resulted in the relatively low overall cure and survival rates for NSCLC. Autophagy is a conserved process that allows cells to recycle unused or damaged organelles and cellular components. It has been reported to be related to the progression of NSCLC and resistance to targeted therapy and cytotoxic chemotherapy. Therefore, autophagy is considered as a potential therapeutic target for NSCLC. Mounting results have been reported about the combination of tyrosine kinase inhibitors and inhibitors of autophagy in models of NSCLC. This review aims to provide a comprehensive review on the roles of autophagy in NSCLC, focusing on related clinical data of agents that regulate autophagy in NSCLC. Furthermore, this study will provide a theoretical basis for further improvement of autophagy-based cancer therapy.

The Roles of Beclin 1 Expression in Gastric Cancer: A Marker for Carcinogenesis, Aggressive Behaviors and Favorable Prognosis, and a Target of Gene Therapy

Beclin 1 is encoded by Becn1, and plays a role in tumorigenesis, neurodegeneration, apoptosis and autophagy. Here, the aggressive phenotypes and relevant proteins were examined after Beclin 1 expression was altered in gastric cancer cells. We also observed the effects of Beclin 1 on gastric carcinogenesis using Becn1 knockout mice. Finally, clinicopathological significances of Beclin 1 expression were analyzed using meta- and bioinformatics analyses. Becn1 overexpression was found to inhibit proliferation, glucose metabolism, migration and invasion of gastric cancer cells, whereas its knockdown caused the opposite effects. Beclin 1 suppressed the tumor growth by decreasing proliferation and increasing apoptosis. The heterozygous abrogation of Becn1 in gastric pit, parietal and chief cells could not cause any epithelial lesion. Beclin 1-mediated chemoresistance was closely linked to the autophagy, Bax underexpression, and the overexpression of Bcl-2, LRP1, MDR1, and ING5. Bioinformatics analysis showed higher Becn1 mRNA expression in intestinal- than diffuse-type carcinomas (P<0.05), and in male than female gastric cancer patients (P<0.05). Becn1 hyperexpression was positively associated with both overall and progression-free survival rates of the cancer patients (P<0.05). Meta-analysis showed that down-regulated Beclin 1 expression in gastric cancer was positively with lymph node metastasis, TNM staging, dedifferentiation and poor prognosis (P<0.05). Becn1-related signal pathways in gastric cancer included prostate, lung, renal, colorectal, endometrial and thyroid cancers, glioma, and leukemia, the metabolism of amino acid, lipid and sugar, and some signal pathways of insulin, MAPK, TRL, VEGF, JAK-STAT, chemokine, p53, lysosome, peroxidome and ubiquitin-mediated protein degradation (P<0.05). These suggested that Beclin 1 might be considered as a potential marker of gastric carcinogenesis, aggressiveness and prognostic prediction, and as a target of gene therapy in gastric cancer.

Beclin-1 expression is associated with prognosis in a Bcl-2-dependent manner in non-small cell lung cancer

Beclin-1 and Bcl-2 expression abnormalities have been confirmed in different types of cancer. As important regulators of autophagy and apoptosis, respectively, these molecules serve a complex role in tumorigenesis. However, limited information is currently available regarding the association between Beclin-1 and Bcl-2 in (NSCLC). In the present study, the expression levels of Beclin-1 and Bcl-2 were detected in lung cancer tissues, and their prognostic significance was analyzed for NSCLC. A total of 120 patients with lung cancer who underwent surgical resection were included in the present study. Beclin-1 and Bcl-2 expression was assessed using immunohistochemistry and their associations with the overall survival (OS) in patients with NSCLC was examined. The expression rate of Beclin-1 was significantly lower in NSCLC tissues compared with that in adjacent tissues, whereas the expression rate of Bcl-2 was significantly higher in lung cancer tissues compared with that in adjacent tissues. Additionally, Beclin-1 and Bcl-2 protein expression was strongly associated (P<0.05) in NSCLC. Patients with NSCLC with low Beclin-1 expression were in more advanced stages, with more lymph node metastasis and more poorly differentiated tumors. Similarly, patients with NSCLC with high Bcl-2 expression were also in a more advanced stage and had more lymph node metastasis. Cox regression analysis revealed that the association between Bcl-2 expression and survival was not significant, while a multivariate analysis revealed that Beclin-1 expression was significantly associated with OS. Notably, Beclin-1 expression was significantly associated with OS only in patients with high Bcl-2 expression. In conclusion, the present data indicated that the autophagy activity is decreased in NSCLC. Beclin-1 expression was downregulated, while Bcl-2 expression was upregulated in NSCLC tissues compared with that in adjacent tissues. Additionally, these two proteins were associated with the occurrence and progression of NSCLC. Beclin-1 may be a promising prognostic marker for patients with NSCLC with high Bcl-2 expression. The present findings provided a more accurate prognostic assessment for patients with NSCLC. Furthermore, they may be used to actively follow-up and promptly treat patients with a poor prognosis, which may benefit a greater number of patients with NSCLC.

The Prognostic Value of Autophagy-Related Markers Bclin-1 and LC-3 in Colorectal Cancers: A Systematic Review and Meta-analysis

Objective

At present, the relationship between autophagosomes and the prognosis of various cancers has become a subject of active investigation. A series of studies have demonstrated the correlation between autophagy microtubule-associated protein light chain 3 (LC-3), Beclin-1, and colorectal cancer (CRC). Since autophagy has dual regulatory roles in tumors, the results of this correlation are also uncertain. Hence, we summarized the relationship between Beclin-1, LC-3, and CRC using systematic reviews and meta-analysis to clarify their prognostic significance in it.

Methods

PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched online up to April 1, 2019. The quality of the involving studies was assessed against the Newcastle-Ottawa Scale (NOS). Pooled hazard ratio (HR) and 95% confidence interval (CI) in a fixed or random effects model were used to assess the strength of correlation between Beclin-1, LC-3, and CRC.

Results

A total of 9 articles were collected, involving 2,297 patients. Most literatures scored more than 6 points, suggesting that the quality of our including research was acceptable. Our finding suggested that the expression of Beclin-1 was not associated with overall survival (HR = 0.68, 95% CI (0.31–1.52), P=0.351). Nonetheless, LC-3 expression exerted significant impact on OS (HR = 0.51, 95% CI (0.35–0.74), P < 0.05). Subgroup analysis exhibited that Beclin-1 expression was associated with OS at TNM stage III (HR = 0.04, 95% CI = 0.02–0.08, P < 0.05), surgical treatment (HR = 1.53, 95% CI (1.15–2.02), P=0.003), and comprehensive treatment (HR = 0.27 95% CI (0.08–0.92), P=0.036), respectively. Similarly, the results showed the increased LC-3 expression in CRC was related to OS in multivariate analyses (HR = 0.44, 95% CI (0.34–0.57), P < 0.05), stages (HR = 0.51, 95% CI (0.35–0.74), P < 0.05), and comprehensive treatment (HR = 0.44, 95% CI (0.34–0.57), P < 0.05).

Conclusions

Autophagy-related proteins of LC-3 might be an important marker of CRC progression. However, since the number of the original studies was limited, more well-designed, large-scale, high-quality studies are warranted to provide more convincing and reliable information.

Hypoxia as a signal for prison breakout in cancer

PURPOSE OF REVIEW

We discuss recent discoveries in hypoxic cellular pathophysiology and explore the interplay between hypoxic malignant cells and other stromal elements. This review will provide an update on the effects of hypoxia on cancer outcomes and therapeutic resistance.

RECENT FINDINGS

Hypoxia has been discovered to be a key driver for tumor progression, both because of impacts on tumor cells and separately on the wider tumor microenvironment. The latter effects occur via epithelial mesenchymal transition, autophagy and metabolic switching. Through epithelial mesenchymal transition, hypoxia both drives metastasis and renders key target tissues receptive to metastasis. Autophagy is a double-edged sword which requires greater understanding to ascertain when it is a threat. Metabolic switching allows tumor cells to access hypoxic survival mechanisms even under normoxic conditions.Every element of the malignant stroma contributes to hypoxia-driven progression. Exosomal transfer of molecules from hypoxic tumor cells to target stromal cell types and the importance of microRNAs in intercellular communication have emerged as key themes.Antiangiogenic resistance can be caused by hypoxia-driven vasculogenic mimicry. Beyond this, hypoxia contributes to resistance to virtually all oncological treatment modalities.

SUMMARY

Recent advances have moved us closer to being able to exploit hypoxic mechanisms to overcome hypoxia-driven progression and therapy failure.

Functional roles of lncRNAs and its potential mechanisms in neuropathic pain

Neuropathic pain (NP) is ranked as one of the major forms of chronic pain and emerges as a direct consequence of a lesion or disease affecting the somatosensory nervous system. Despite great advances into the mechanisms of NP, clinical practice is still not satisfactory. Fortunately, progress in elucidating unique features and multiple molecular mechanisms of long non-coding RNAs (lncRNAs) in NP has emerged in the past 10 years, suggesting that novel therapeutic strategies for pain treatment may be proposed. In this review, we will concentrate on recent studies associated with lncRNAs in NP. First, we will describe the alterations of lncRNA expression after spinal cord injury (SCI) and peripheral nerve injury (PNI), and then we illustrate the role of some specific lncRNAs in detail, which may offer new insights into our understanding of the etiology and pathophysiology of NP. Finally, we put special emphasis on the altered expression of lncRNAs in the diverse biological process of NP. Recent advances we summarized above in the development of NP may facilitate translation of these findings from bench to bedside in the future.