MPP7 promotes the migration and invasion of breast cancer cells via EGFR/AKT signaling

Pan-cancer analysis of the role of MPP7 in human tumors

MAGUK p55 subfamily member 7, a part of the membrane palmitoylated protein subfamily, is an essential adapter that promotes epithelial cell polarity and has increasing significance in multiple cancers, including esophageal cancer, clear cell renal cell carcinoma, breast cancer, and pancreatic ductal adenocarcinoma. This paper aims to determine the effect of the MAGUK p55 subfamily member 7 in various tumor types using The Cancer Genome Atlas and Genotype-Tissue Expression database. A variety of software and web platforms, such as cBioPortal, GEPIA2, TIMER2, UALCAN, R, STRING, and DAVID, were used to obtain and analyze data. Notably, low expression of MAGUK p55 subfamily member 7 was observed in most cancers. In addition, low expression of MAGUK p55 subfamily member 7 predicted poor prognoses in cancer patients. Mutation was the most frequent genetic alteration type in MAGUK p55 subfamily member 7, with the phosphorylation sites identified as S412 and S490 in various cancers. Furthermore, expression of MAGUK p55 subfamily member 7 was associated with cancer-related fibroblasts and CD8+ T cells. Gene enrichment analysis indicated that MAGUK p55 subfamily member 7 influences cancer through the Rap1 signaling pathway. This paper elucidates the biological significance of MAGUK p55 subfamily member 7 in human pan-cancer prognosis and immune response.

Duodenal-Jejunal bypass improves metabolism and re-models extra cellular matrix through modulating ceRNA network

BACKGROUND

Bariatric surgery (BS) is an effective approach in treating obesity and ameliorating T2DM with obesity. Our previous studies demonstrated that duodenal-jejunal bypass (DJB) altered long non-coding RNAs (lncRNAs) in the gastrointestinal system, which is associated with modulation of lipid metabolism, and glycemic control through entero-pancreatic axis and gut-brain axis. The adipose non-coding RNA expression profile and the underlying competing endogenous RNA (ceRNA) regulatory network pattern post DJB needs further research and investigation.

RESULTS

In this study, we compared the lncRNAs, circular RNAs (circRNAs) and messenger RNAs (mRNAs) expression in adipose tissues between the sham group and the DJB group. 2219 differentially expressed mRNAs (DEmRNAs), 722 differential expression of lncRNAs (DElncRNAs) and 425 differential expression of circRNAs (DEcircRNAs) were identified. GO terms and KEGG pathways analysis of the DEmRNAs implied that the dysregulated adipose mRNAs were associated with lipid, amino acid metabolism, insulin resistance, and extra cellular matrix (ECM)-related pathways. Moreover, via analyzing ceRNA regulatory networks of DElncRNAs and DEcircRNAs, 31 hub DE mRNAs, especially Mpp7, 9330159F19Rik, Trhde. Trdn, Sorbs2, were found on these pathways.

CONCLUSIONS

The role of DJB in adipose tends to remodel ECM and improve the energy metabolism through the ceRNA regulatory network.

A common variant SNP rs1937810 in the MPP7 gene contributes to the susceptibility of breast cancer in the Chinese Han population

BACKGROUND

Breast cancer (BC) is common cancer caused by environmental factors and genetic ones. Previous evidence has linked gene MAGUK P55 Scaffold Protein 7 (MPP7) to BC, despite that there has been no research evaluating the relationship between MPP7 genetic polymorphisms and BC susceptibility. We aimed to investigate the potential association of the MPP7 gene with the susceptibility to BC in Han Chinese individuals.

METHODS

In total, 1390 patients with BC and 2480 controls were enrolled. For genotyping, 20 tag SNPs were chosen. The serum levels of protein MPP7 were measured in all subjects using an enzyme-linked immunosorbent assay. Genetic association analysis was performed in both genotypic and allelic modes, and the relationship between BC patients' clinical features and genotypes of relevant SNPs was examined. The functional implications of significant markers were also evaluated.

RESULTS

After adjusting for Bonferroni correction, SNP rs1937810 was found to be significantly associated with the risk of BC (p = 1.19 × 10-4 ). The odds ratio of CC genotypes in BC patients was 49% higher than in controls (1.49 [1.23-1.81]). Serum MPP7 protein levels were significantly higher in BC patients than in controls (p < 0.001). The protein level of the CC genotype was the highest, and that of the CT and TT genotypes decreased in turn (both p < 0.001).

CONCLUSIONS

Our results linked SNP rs1937810 to the susceptibility of BC and the clinical features of BC patients. This SNP is also proved to be significantly related to the serum level of protein MPP7 in both BC patients and controls.

MPP7 as a Novel Biomarker of Esophageal Cancer: MPP7 Knockdown Inhibits Esophageal Cancer Cell Migration and Invasion

MAGUK p55 scaffold protein 7 (MPP7) is a member of the stardust family of membrane-associated guanosine kinase protein P55 and plays a role in the establishment of epithelial cell polarity. However, its potential implication in human esophageal cancer is unclear. In this study, we investigated the expression profile of MPP7 and its functional impact on esophagus cancer. Expression analyses of immunohistochemical microarrays with survival and prognostic information of 103 patients with esophageal cancer demonstrated that MPP7 was overexpressed in 52 patients, who showed poor survival rates. The transcriptional expression of MPP7 in esophageal cancer in TCGA database increased successively from normal epithelial, to esophageal adenocarcinoma, to esophageal squamous cell carcinoma. Transcriptome sequencing after MPP7 knockdown in esophageal carcinoma cells showed that wound-healing-associated proteins were down-regulated, and the TGF-β pathway was one of the important signaling pathways. A loss-of-function study showed that the knockdown of MPP7 inhibited cell migration and invasion. These results could be verified in a model of tumor cells injected into the tail vein and subcutaneous tumor of nude mice. Herein, our results indicated that MPP7 could have an oncogenic role in human esophagus cancer, thus demonstrating its potential as a novel biomarker for the diagnosis and/or treatment of esophagus cancer.

Multi-Objective Artificial Bee Colony Algorithm Based on Scale-Free Network for Epistasis Detection

In genome-wide association studies, epistasis detection is of great significance for the occurrence and diagnosis of complex human diseases, but it also faces challenges such as high dimensionality and a small data sample size. In order to cope with these challenges, several swarm intelligence methods have been introduced to identify epistasis in recent years. However, the existing methods still have some limitations, such as high-consumption and premature convergence. In this study, we proposed a multi-objective artificial bee colony (ABC) algorithm based on the scale-free network (SFMOABC). The SFMOABC incorporates the scale-free network into the ABC algorithm to guide the update and selection of solutions. In addition, the SFMOABC uses mutual information and the K2-Score of the Bayesian network as objective functions, and the opposition-based learning strategy is used to improve the search ability. Experiments were performed on both simulation datasets and a real dataset of age-related macular degeneration (AMD). The results of the simulation experiments showed that the SFMOABC has better detection power and efficiency than seven other epistasis detection methods. In the real AMD data experiment, most of the single nucleotide polymorphism combinations detected by the SFMOABC have been shown to be associated with AMD disease. Therefore, SFMOABC is a promising method for epistasis detection.

Breast cancer cell-derived extracellular vesicles transfer miR-182-5p and promote breast carcinogenesis via the CMTM7/EGFR/AKT axis

Background

Extracellular vesicles (EVs) derived from tumor cells are implicated in the progression of malignancies through the transfer of molecular cargo microRNAs (miRNAs or miRs). We aimed to explore the role of EVs derived from breast cancer cells carrying miR-182-5p in the occurrence and development of breast cancer.

Methods

Differentially expressed miRNAs and their downstream target genes related to breast cancer were screened through GEO and TCGA databases. miR-182-5p expression was examined in cancer tissues and adjacent normal tissues from patients with breast cancer. EVs were isolated from breast cancer cell line MDA-MB-231 cells and identified. The gain- and loss-of function approaches of miR-182-5p and CKLF-like MARVEL transmembrane domain-containing 7 (CMTM7) were performed in MDA-MB-231 cells and the isolated EVs. Human umbilical vein endothelial cells (HUVECs) were subjected to co-culture with MDA-MB-231 cell-derived EVs and biological behaviors were detected by CCK-8 assay, flow cytometry, immunohistochemical staining, Transwell assay and vessel-like tube formation in vitro. A xenograft mouse model in nude mice was established to observe the tumorigenesis and metastasis of breast cancer cells in vivo.

Results

miR-182-5p was highly expressed in breast cancer tissues and cells, and this high expression was associated with poor prognosis of breast cancer patients. miR-182-5p overexpression was shown to promote tumor angiogenesis in breast cancer. Moreover, our data indicated that miR-182-5p was highly enriched in EVs from MDA-MD-231 cells and then ultimately enhanced the proliferation, migration, and angiogenesis of HUVECs in vitro and in vivo. Moreover, we found that CMTM7 is a target of miR-182-5p. EVs-miR-182-5p promotes tumorigenesis and metastasis of breast cancer cells by regulating the CMTM7/EGFR/AKT signaling axis.

Conclusions

Taken altogether, our findings demonstrates that EVs secreted by breast cancer cells could carry miR-182-5p to aggravate breast cancer through downregulating CMTM7 expression and activating the EGFR/AKT signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10020-021-00338-8.