Expression of LC3, LAMP2, KEAP1 and NRF2 in Salivary Adenoid Cystic Carcinoma

Targeting kelch-like (KLHL) proteins: achievements, challenges and perspectives

Kelch-like proteins (KLHLs) are a large family of BTB-containing proteins. KLHLs function as the substrate adaptor of Cullin 3-RING ligases (CRL3) to recognize substrates. KLHLs play pivotal roles in regulating various physiological and pathological processes by modulating the ubiquitination of their respective substrates. Mounting evidence indicates that mutations or abnormal expression of KLHLs are associated with various human diseases. Targeting KLHLs is a viable strategy for deciphering the KLHLs-related pathways and devising therapies for associated diseases. Here, we comprehensively review the known KLHLs inhibitors to date and the brilliant ideas underlying their development.

Prediction significance of autophagy-related genes in survival probability and drug resistance in diffuse large B-cell lymphoma

BACKGROUND/AIMS

Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkin lymphoma, has significant prognostic heterogeneity. This study aimed to generate a prognostic prediction model based on autophagy-related genes for DLBCL patients.

METHODS

Utilizing bioinformatics techniques, we analyzed the clinical information and transcriptome data of DLBCL patients from the Gene Expression Omnibus (GEO) database. Through unsupervised clustering, we identified new autophagy-related molecular subtypes and pinpointed differentially expressed genes (DEGs) between these subtypes. Based on these DEGs, a prognostic model was constructed using Cox and Lasso regression. The effectiveness, accuracy, and clinical utility of this prognostic model were assessed using numerous independent validation cohorts, survival analyses, receiver operating characteristic (ROC) curves, multivariate Cox regression analysis, nomograms, and calibration curves. Moreover, functional analysis, immune cell infiltration, and drug sensitivity analysis were performed.

RESULTS

DLBCL patients with different clinical characterizations (age, molecular subtypes, ECOG scores, and stages) showed different expression features of autophagy-related genes. The prediction model was constructed based on the eight autophagy-related genes (ADD3, IGFBP3, TPM1, LYZ, AFDN, DNAJC10, GLIS3, and CCDC102A). The prognostic nomogram for overall survival of DLBCL patients incorporated risk level, stage, ECOG scores, and molecular subtypes, showing excellent agreement between observed and predicted outcomes. Differences were noted in the proportions of immune cells (native B cells, Treg cells, CD8+ T cell, CD4+ memory activated T cells, gamma delta T cells, macrophages M1, and resting mast cells) between high-risk and low-risk groups. LYZ and ADD3 exhibited correlations with drug resistance to most chemotherapeutic drugs.

CONCLUSIONS

This study established a novel prognostic assessment model based on the expression profile of autophagy-related genes and clinical characteristics of DLBCL patients, explored immune infiltration and predicted drug resistance, which may guide precise and individualized immunochemotherapy regimens.

Immunoexpression of Autophagy-Related Proteins in Salivary Gland Tumors: An Exploratory Study

BACKGROUND

Autophagy is a cellular survival mechanism involved in several human diseases, but its participation in the development of salivary gland tumors is not fully understood. This study investigated the immunoexpression of autophagy-related proteins (autophagy-related 7 [Atg7], microtubule-associated protein 1 light chain 3A [LC3A], microtubule-associated protein 1 light chain 3B [LC3B], protein p62 [p62], and phosphorylated mammalian target of rapamycin [p-mTOR]) in pleomorphic adenoma (PA), polymorphous adenocarcinoma (PAC), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC) of salivary glands.

METHODS

Twenty PAs, 20 PACs, 20 MECs, and 14 ACCs were selected. The percentages of cytoplasmic and nuclear positivity for autophagy-related proteins in neoplastic cells were assessed and correlated with histopathological parameters.

RESULTS

Cytoplasmic immunoexpression of Atg7 was observed in all groups, with high median percentages of positivity. Regarding LC3A and LC3B, cytoplasmic immunoexpression was found in most PACs (95%) and in all cases of PA, MEC and ACC, with the highest percentages of positivity in PACs and PAs (p < 0.005). ACCs exhibited lower cytoplasmic immunoexpression of p-mTOR (p < 0.005) and lower nuclear expression of p62 (p < 0.05) when compared to PAs, PACs and MECs. Low nuclear immunoexpression of Atg7, LC3A and p-mTOR and absence of nuclear staining for LC3B were observed in all groups. Regarding histopathological parameters of PAs, MECs and ACCs, there were no significant differences in the expression of autophagy-related proteins. In all groups, positive correlations were observed between the immunoexpression of some autophagy-related proteins (p < 0.05).

CONCLUSIONS

The results suggest the participation of autophagy in the pathogenesis of PA, PAC, MEC, and ACC of salivary glands. Upregulation of autophagy and reduced nuclear translocation of p62 may contribute to the aggressive biological behavior of salivary gland ACC.

Analysis of Cytological Misdiagnosis and Oversight of Adenoid Cystic Carcinoma of Salivary Gland

OBJECTIVE

In this article on adenoid cystic carcinoma (ACC) of salivary gland, we intend to summarize the causes of misdiagnosis and oversight of ACC hoping to improve cytological diagnostic accuracy, clinical management and patient treatment.

METHODS

The study retrospectively reviewed 32 patients with ACC of salivary gland, registered at the Affiliated Hospital of Southwest Medical University from July 2014 to June 2021. These cases were diagnosed by FNA and surgical excision biopsy. All cytopathological results were retrospectively categorized according to Milan system for reporting salivary gland cytopathology (MSRSGC). The accuracy of FNA was verified by surgical excision biopsy.

RESULTS

Of these 32 patients, 16 (50.0%) cases were male, and 16 (50.0%) were female. Their age ranged from 21 to 79 years, with an average age of 50.32 years. The highest incidence (15/32, 46.9%) of ACC was observed in patients between 41 and 50 years of age. 10 cases (31.3%) occurred in the parotid gland, 9 cases (28.1%) in the submandibular gland, 9 cases (28.1%) in the sublingual gland, 3 cases (9.4%) in the palate, and 1 case (3.1%) in the lip. Among the 32 cases of ACC, 23 cases (71.9%) were classified to VI, 4 cases (12.5%) to IVa, and 5 cases (15.6%) to II by MSRSGC. A comparison of the FNA results with biopsy showed that the accuracy of FNA in ACC of salivary gland is 71.9%. Being able to identify the cytomorphological features is the key factor for accurate diagnosis of ACC of the salivary gland.

CONCLUSION

Our results confirm that FNA is an important initial screening in the diagnosis of ACC of salivary gland. Increased study of the cytomorphology of ACC is beneficial for more accurate diagnosis of ACC, to reduce misdiagnosis and oversight.

The anti-tumor effect of proteasome inhibitor MG132 for human adenoid cystic carcinoma: correlate with the emerging role of Nrf2/Keap1 signaling pathway

BACKGROUND

Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary gland tumors. Moreover, the unique biological characteristics and complex structures of ACC contribute to its poor survival rates. Recently, proteasome inhibitors have been shown to elicit satisfactory therapeutic effects in the treatment of certain solid tumors, but few studies have been implemented to investigate the effects of proteasome inhibitor therapy for ACC.

METHODS

In this present study, cell counting kit-8 assay and flow cytometry assay were performed to examine the effects of proteasome inhibitor (MG132) on cell viability and apoptosis. We applied western blot and immunofluorescence staining to explore the expression of the Nrf2/Keap1 signaling pathway and P62, additionally Nrf2 inhibitor (ML385) was utilized to evaluate the role of Nrf2/Keap1 signaling pathway in MG132-induced cell apoptosis.

RESULTS

Our data indicated that MG132 significantly suppressed the growth of ACC-83 cells(MG132 10µM P = 0.0046; 40µM P = 0.0033; 70µM P = 0.0007 versus control) and induced apoptosis (MG132 10µM P = 0.0458; 40µM P = 0.0018; 70µM P = 0.0087 versus control). The application of MG132 induced the up-regulation of Nrf2/Keap1 signaling pathway. Furthermore, inhibition of Nrf2 attenuated the therapeutic effects of MG132 for ACC (both ML385 + MG132 10µM P = 0.0013; 40µM P = 0.0057; 70µM P = 0.0003 versus MG132). P < 0.05 was considered statistically significant.

CONCLUSIONS

Our results revealed that proteasome inhibitors MG132 could inhibit the cell viability and induce the apoptosis of ACC through Nrf2/Keap1 signaling pathway.

Targeting Cytoprotective Autophagy to Enhance Anticancer Therapies

Autophagy is a highly regulated multi-step process that occurs at the basal level in almost all cells. Although the deregulation of the autophagy process has been described in several pathologies, the role of autophagy in cancer as a cytoprotective mechanism is currently well established and supported by experimental and clinical evidence. Our understanding of the molecular mechanism of the autophagy process has largely contributed to defining how we can harness this process to improve the benefit of cancer therapies. While the role of autophagy in tumor resistance to chemotherapy is extensively documented, emerging data point toward autophagy as a mechanism of cancer resistance to radiotherapy, targeted therapy, and immunotherapy. Therefore, manipulating autophagy has emerged as a promising strategy to overcome tumor resistance to various anti-cancer therapies, and autophagy modulators are currently evaluated in combination therapies in several clinical trials. In this review, we will summarize our current knowledge of the impact of genetically and pharmacologically modulating autophagy genes and proteins, involved in the different steps of the autophagy process, on the therapeutic benefit of various cancer therapies. We will also briefly discuss the challenges and limitations to developing potent and selective autophagy inhibitors that could be used in ongoing clinical trials.

Identifying an Eight-Gene Signature to Optimize Overall Survival Prediction of Esophageal Adenocarcinoma Using Bioinformatics Analysis of ceRNA Network

Background and Aims

Esophageal adenocarcinoma (EAC) patients usually have a poor prognosis without early diagnosis. In this study, we aimed to identify a novel signature to improve the prediction of overall survival (OS) in EAC.

Methods

Eighty-one and 68 samples from The Cancer Genome Atlas (TCGA) and GSE19417 dataset were included for discovery and survival validation, respectively. In the TCGA cohort, a total of 1,811 DEmRNAs, 1,096 DElncRNAs, and 31 DEmiRNAs were identified between EAC and normal esophagus tissues. A mRNA–miRNA–lncRNA ceRNA network of EAC was established, which consisted of 94 DEmRNAs, 13 DEmiRNAs, and 46 DElncRNAs.

Results

In this study, we identified eight genes (UBE2B, LAMP2, B3GNT2, TAF9B, EFNA1, PHF8, PIGA, and NEURL1) which were related to survival in EAC. The independent external microarray data from the Gene Expression Omnibus (GEO) was used to validate these candidate genes. The prognostic ability of the signature was also validated in EAC patients in our hospital. Patients assigned to the high-risk group had a poor overall survival rate compared with the low-risk.

Conclusion

The current study provides novel insights into the mRNA-related ceRNA network in EAC and the eight mRNA biomarkers may be independent prognostic signatures in predicting the survival of EAC patients.

Ginsenoside Rh2 induces DNA damage and autophagy in vestibular schwannoma is dependent of LAMP2 transcriptional suppression

Ginsenoside Rh2 (G-Rh2), a component of ginseng extraction, exerted anti-tumor property in the occurrence and progress of human tumors. Vestibular schwannoma (VS) is a kind of benign tumor. Extraction of traditional Chinese herb has been applied to treat VS as adjuvant therapy. Nevertheless, G-Rh2-related molecular mechanisms in VS progress are not yet clear. The purpose of current study is to unveil the function and potential molecular mechanism of Rh2 in VS cellular functions. At first, the viability and apoptosis of VS cells treated with different concentrations of Rh2 were assessed. Autophagy and DNA damage response can be induced by multiple drugs. Here, we observed the changes of autophagy and DNA damage in Rh2-induced VS cells. Based on the experimental data, treatment with Rh2 contributed to cell apoptosis by inducing DNA damage and suppressing DNA damage. LAMP2 (lysosomal associated membrane protein 2), an autophagy inducer, was downregulated in Rh2-treated VS cells. Through mechanism study, we determined that Rh2 led to the transcriptional inactivation of LAMP2 by downregulating its transcription activator NR2F2 (nuclear receptor subfamily 2 group F member 2). In addition, NR2F2 overexpression recovered the role of Rh2 in cell functions, which was further rescued by the silence of LAMP2. Collectively, our study unveiled a novel NR2F2/LAMP2 axis in Rh2-mediated VS cells, which potentially contributes to the therapy for VS.

Potential biomarkers for the early diagnosis of colorectal adenocarcinoma - transcriptomic analysis of four clinical stages

BACKGROUNDS

Colorectal cancer is the third most common cancer in economically developed countries. Molecular studies and, in particular, gene expression have contributed to advances in the diagnosis and treatment of many cancers. Genes can be molecular and therapeutic markers, but because of the large molecular diversity in colorectal cancer the knowledge is not yet fully established. Probably one of the most crucial processes during early cancer development is inflammation. The inflammatory response in the tumor is an important indicator of molecular etiology and later of cancer progression.

OBJECTIVE

The aim of this work is to identify potential biomarkers for early stage of colorectal adenocarcinoma in patients' bowel tissues using transcriptomic analysis.

METHODS

Expression of the inflammatory response genes of colorectal cancer at all clinical stages (I-IV) and control of the bowel were evaluated by oligonucleotide microarrays.

RESULTS

Based on statistical analysis many differentially expressed genes were selected. LCK (LCK Proto-Oncogene, Src Family Tyrosine Kinase), GNLY (granulysin), SLC6A6 (Solute-Carrier Family 6 Member 6) and LAMP2 (Lysosomal Associated Membrane Protein 2) were specific for the early stage of the disease. These genes had the properties of the good biomarkers.

CONCLUSIONS

The expression of LCK, GNLY, SLC6A6 and LAMP2 genes could be valuable potential diagnostic biomarkers of the early stage of colorectal adenocarcinoma.

"Stealth dissemination" of macrophage-tumor cell fusions cultured from blood of patients with pancreatic ductal adenocarcinoma

Here we describe isolation and characterization of macrophage-tumor cell fusions (MTFs) from the blood of pancreatic ductal adenocarcinoma (PDAC) patients. The MTFs were generally aneuploidy, and immunophenotypic characterizations showed that the MTFs express markers characteristic of PDAC and stem cells, as well as M2-polarized macrophages. Single cell RNASeq analyses showed that the MTFs express many transcripts implicated in cancer progression, LINE1 retrotransposons, and very high levels of several long non-coding transcripts involved in metastasis (such as MALAT1). When cultured MTFs were transplanted orthotopically into mouse pancreas, they grew as obvious well-differentiated islands of cells, but they also disseminated widely throughout multiple tissues in "stealth" fashion. They were found distributed throughout multiple organs at 4, 8, or 12 weeks after transplantation (including liver, spleen, lung), occurring as single cells or small groups of cells, without formation of obvious tumors or any apparent progression over the 4 to 12 week period. We suggest that MTFs form continually during PDAC development, and that they disseminate early in cancer progression, forming "niches" at distant sites for subsequent colonization by metastasis-initiating cells.

Gene expression changes in bioceramic paste-treated human dental pulp cells

We evaluated the gene expression profiles of human dental pulp cells exposed to iRoot BP using microarray after 24 and 72 h. The results were verified using quantitative reverse transcriptase PCR analysis. Of the 36,000 transcripts arrayed, 21 were up-regulated and 15 were down-regulated by more than two fold. The largest group of up-regulated genes included those involved in nucleobase-containing compound metabolic processes, cell communication, protein metabolic processes, developmental processes, and biological regulation. The largest groups of down-regulated genes were those involved in cell communication, development, and biological regulation processes. In conclusion, iRoot BP affects the expression of genes involved in different biological processes in human dental pulp cells. (J Oral Sci 58, 307-315, 2016).

Expression and associations of TRAF1, BMI-1, ALDH1, and Lin28B in oral squamous cell carcinoma

Tumor necrosis factor receptor-associated factor 1, an adaptor protein of tumor necrosis factor 2, is involved in classical nuclear factor (NF)-κB activation and lymphocyte recruitment. However, less is known about the expression and association of tumor necrosis factor receptor-associated factor 1 with cancer stem cell markers in oral squamous cell carcinoma. This study aimed to investigate the expression of tumor necrosis factor receptor-associated factor 1 and stem cell characteristic markers (lin28 homolog B, B cell-specific Moloney murine leukemia virus integration site 1, and aldehyde dehydrogenase 1) in oral squamous cell carcinoma and analyze their relations. Paraffin-embedded tissues of 78 oral squamous cell carcinomas, 39 normal oral mucosa, and 12 oral dysplasia tissues were employed in tissue microarrays, and the expression of tumor necrosis factor receptor-associated factor 1, B cell-specific Moloney murine leukemia virus integration site 1, aldehyde dehydrogenase 1, and lin28 homolog B was measured by immunohistostaining and digital pathological analysis. The expression of tumor necrosis factor receptor-associated factor 1 was higher in the oral squamous cell carcinoma group as compared with the expression in the oral mucosa (p < 0.01) and oral dysplasia (p < 0.001) groups. In addition, the expression of tumor necrosis factor receptor-associated factor 1 was associated with those of B cell-specific Moloney murine leukemia virus integration site 1, aldehyde dehydrogenase 1, and lin28 homolog B (p = 0.032, r² = 0.109; p < 0.0001, r² = 0.64; and p < 0.001, r² = 0.16) in oral squamous cell carcinoma. The patient survival rate was lower in the highly expressed tumor necrosis factor receptor-associated factor 1 group, although the difference was not significant. The clustering analysis showed that tumor necrosis factor receptor-associated factor 1 was most related to aldehyde dehydrogenase 1. These findings suggest that tumor necrosis factor receptor-associated factor 1 has potential direct/indirect regulations with the cancer stem cell markers in oral squamous cell carcinoma, which may help in further analysis of the cancer stem cell characteristics.

Mutations and expression of the NFE2L2/KEAP1/CUL3 pathway in Chinese patients with lung squamous cell carcinoma

BACKGROUND

Recent studies have reported an abnormally high alteration rate in the nuclear factor erythroid 2-like 2 (NFE2L2)/kelch-like ECH-associated protein 1 (KEAP1)/cullin 3 (CUL3) pathway. But the status of this pathway in Chinese patients with lung squamous cell carcinoma (SqCC) has not been thoroughly studied, and there are many uncertainties regarding the expression of pathway intermediates.

METHODS

cDNA sequencing and TaqMan qRT-PCR were carried out in paired cancer and adjacent normal samples obtained from 100 Chinese patients with lung SqCC. Immunohistochemical staining was performed in 50 other paraffin-embedded specimens.

RESULTS

We detected 47 mutations in 36 patients (36%), and 143 single nucleotide polymorphism (SNP) in 59 patients (59%), of which 41 mutations and 31 SNPs resulted in amino acid (AA) and possibly functional changes. By combining qRT-PCR and immunohistochemistry staining, we confirmed that the expression of NFE2L2 and KEAP1 were highly increased, while the expression of CUL3 was not significantly changed in lung SqCC samples from Chinese patients.

CONCLUSIONS

Considering the frequent mutations and abnormal expression, the NFE2L2/KEAP1/CUL3 pathway may play an important role in the therapy of Chinese patients with lung SqCC.