The Emerging Roles of π Subunit-Containing GABAA Receptors in Different Cancers

GABA regulates the proliferation and apoptosis of head and neck squamous cell carcinoma cells by promoting the expression of CCND2 and BCL2L1

Gamma-aminobutyric acid (GABA) is a multifunctional molecule that is widely present in the nervous system and nonneuronal tissues. It plays pivotal roles in neurotransmission, regulation of secretion, cell differentiation, proliferation, and tumorigenesis. However, the exact mechanisms of GABA in head and neck squamous cell carcinomas (HNSCCs) are unknown. We took advantage of RNA sequencing in this work and uncovered the potential gene expression profiles of the GABA-treated HNSCC cell line HN4-2. We found that the expression of CCND2 and BCL2L1 was significantly upregulated. Furthermore, GABA treatment inhibited the cell apoptosis induced by cisplatin and regulated the cell cycle after treatment with cisplatin in HN4-2 cells. Moreover, we also found that GABA could upregulate the expression of CCND2 and BCL2L1 after treatment with cisplatin. Our results not only reveal the potential pro-tumorigenic effect of GABA on HNSCCs but also provide a novel therapeutic target for HNSCC treatment.

Identification of miRNAs and target genes associated with lymph node metastasis in cervical cancer using bioinformatics analysis

This study was designed to identify the differentially expressed miRNAs (DEMs) and genes (DEGs) in metastatic cervical cancer using bioinformatic tools. In this study, fifty-seven DEMs (48 downregulated and 9 upregulated) were identified, among which miR-4459 and miR-3195 expression was negatively associated with overall survival of cervical cancer patients. Then, 476 target DEGs were determined, and protein-protein interaction (PPI) network was constructed. Seventeen hub genes (LONRF2, CCNE2, AURKA, SYT1, NEGR1, PPP1R12B, GABRP, RAD51, CDK1, FBLN5, PRKG1, CDC6, CACNA1C, MEOX2, ANLN, MYLK, and EDNRB) were finally selected to construct the miRNA-hub gene network. Overall, our study discovered the key miRNAs and mRNAs related to lymph node metastasis (LNM) in cervical cancer, which helps discover candidate therapeutic targets for cervical cancer.

Endorsement of TNBC Biomarkers in Precision Therapy by Nanotechnology

Breast cancer is a heterogeneous disease which accounts globally for approximately 1 million new cases annually, wherein more than 200,000 of these cases turn out to be cases of triple-negative breast cancer (TNBC). TNBC is an aggressive and rare breast cancer subtype that accounts for 10-15% of all breast cancer cases. Chemotherapy remains the only therapy regimen against TNBC. However, the emergence of innate or acquired chemoresistance has hindered the chemotherapy used to treat TNBC. The data obtained from molecular technologies have recognized TNBC with various gene profiling and mutation settings that have helped establish and develop targeted therapies. New therapeutic strategies based on the targeted delivery of therapeutics have relied on the application of biomarkers derived from the molecular profiling of TNBC patients. Several biomarkers have been found that are targets for the precision therapy in TNBC, such as EGFR, VGFR, TP53, interleukins, insulin-like growth factor binding proteins, c-MET, androgen receptor, BRCA1, glucocorticoid, PTEN, ALDH1, etc. This review discusses the various candidate biomarkers identified in the treatment of TNBC along with the evidence supporting their use. It was established that nanoparticles had been considered a multifunctional system for delivering therapeutics to target sites with increased precision. Here, we also discuss the role of biomarkers in nanotechnology translation in TNBC therapy and management.

Gamma-Aminobutyric Acid Type A Receptor Subunit Pi is a potential chemoresistance regulator in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the cancers with high morbidity and mortality worldwide. Chemotherapy is commonly used for metastatic or more advanced CRC. The mechanism of CRC chemoresistance is still under active investigation. Therefore, we identify and validate differentially expressed genes (DEGs) between oxaliplatin/5-FU resistant and sensitive CRC cells.

METHODS AND RESULTS

Three datasets of colorectal cancer patients (GSE28691, GSE81006, and GSE77932) from the Gene Expression Omnibus (GEO) database were analyzed and volcano plots for DEGs were generated using the GEO2R tool. The intersection of three GEO datasets showed that GABRP was significantly upregulated in chemo-resistant CRC cells or patients with an adjusted p-value less than 0.01. The potential protein-protein interaction (PPI) network with GABRP was analyzed by the Search Tool for the Retrieval of Interaction Gene/Proteins (STRING) website. The PPI network predicted ANKRD66, CLINT1, HAP1, PLCL1, GABARPAP, GABARAPL1, NSF, GABARAPL2, TRAK2, and CLIC3 had a high likelihood to interact with GABRP. Especially, GABARAP, GABARAPL1, ANKRD66, CLINT1, and CLIC3 were enriched as the most possibly associated proteins with GABRP among the networks. GABRP was significantly more expressed in both oxaliplatin/5-FU resistant CRC cells than in those counterpart sensitive CRC cells using quantitative PCR (qPCR) analysis. Consistently, TCGA, Oncomine, and Human Protein Atlas (HPA) databases confirmed that higher expression of GABRP was robustly found in CRC patients than those in other various cancer types or normal colon tissues.

CONCLUSION

We identify GABRP as a promising drug target to mediate oxaliplatin or 5-FU resistance in CRC. It provided the theoretical basis and potential clinical value for CRC patients.

Gamma-aminobutyric Acid Type A Receptor Subunit Delta as a Potential Therapeutic Target in Gastric Cancer

BACKGROUND

Novel therapeutic targets are needed to improve the poor prognosis of patients with advanced gastric cancer. The aim of this study was to identify a novel therapeutic target for the treatment of GC and to investigate the potential therapeutic value of an antibody raised against the target.

METHODS

We identified gamma-aminobutyric acid type A receptor subunit delta as a candidate therapeutic target by differential transcriptome analysis of metastatic GC tissue and adjacent nontumor tissues. GABRD mRNA levels were analyzed in 230 pairs of gastric tissue by quantitative reverse-transcription polymerase chain reaction. GABRD function was assessed in proliferation, invasion, and apoptosis assays in human GC cell lines expressing control or GABRD-targeting small interfering RNA (siRNA). Mouse anti-human polyclonal GABRD antibodies were generated and assessed for inhibition of GC cell growth in vitro and in a mouse xenograft model of peritoneal GC dissemination.

RESULTS

High GABRD mRNA expression level in primary human GC tissue was associated with poor prognosis. Expression of siGABRD in GC cell lines significantly decreased cell proliferation and invasion and increased apoptosis compared with control siRNA expression. Anti-GABRD polyclonal antibodies inhibited GC cell proliferation in vitro and decreased peritoneal tumor nodule size in the mouse xenograft model.

CONCLUSION

We identified GABRD as novel regulator of GC cell growth and function. GABRD is upregulated in GC tissue and is associated with poor prognosis, suggesting that it may be a potential therapeutic target for GC.

MAGEA11 as a STAD Prognostic Biomarker Associated with Immune Infiltration

Expression of MAGE family member A11 (MAGEA11) is upregulated in different tumors. However, in gastric cancer, the prognostic significance of MAGEA11 and its relationship with immune infiltration remain largely unknown. The expression of MAGEA11 in pan-cancer and the receiver operating characteristic (ROC) and survival impact of gastric cancer were evaluated by The Cancer Genome Atlas (TCGA). Whether MAGEA11 was an independent risk factor was assessed by Cox analysis. Nomograms were constructed from MAGEA11 and clinical variables. Gene functional pathway enrichment was obtained based on MAGEA11 differential analysis. The relationship between MAGEA11 and immune infiltration was determined by the Tumor Immunity Estimation Resource (TIMER) and the Tumor Immune System Interaction Database (TISIDB). Finally, MAGEA11-sensitive drugs were predicted based on the CellMiner database. The results showed that the expression of MAGEA11 mRNA in gastric cancer tissues was significantly higher than that in normal tissues. The ROC curve indicated an AUC value of 0.667. Survival analysis showed that patients with high MAGEA11 had poor prognosis (HR = 1.43, p = 0.034). In correlation analysis, MAGEA11 mRNA expression was found to be associated with tumor purity and immune invasion. Finally, drug sensitivity analysis found that the expression of MAGEA11 was correlated with seven drugs. Our study found that upregulated MAGEA11 in gastric cancer was significantly associated with lower survival and invasion by immune infiltration. It is suggested that MAGEA11 may be a potential biomarker and immunotherapy target for gastric cancer.