Flotillin-1 protein is upregulated in human endometrial cancer and localization shifts from epithelial to stromal with increasing tumor grade

The Deep Proteomics Approach Identified Extracellular Vesicular Proteins Correlated to Extracellular Matrix in Type One and Two Endometrial Cancer

Among gynecological cancers, endometrial cancer is the most common in developed countries. Extracellular vesicles (EVs) are cell-derived membrane-surrounded vesicles that contain proteins involved in immune response and apoptosis. A deep proteomic approach can help to identify dysregulated extracellular matrix (ECM) proteins in EVs correlated to key pathways for tumor development. In this study, we used a proteomics approach correlating the two acquisitions-data-dependent acquisition (DDA) and data-independent acquisition (DIA)-on EVs from the conditioned medium of four cell lines identifying 428 ECM proteins. After protein quantification and statistical analysis, we found significant changes in the abundance (p < 0.05) of 67 proteins. Our bioinformatic analysis identified 26 pathways associated with the ECM. Western blotting analysis on 13 patients with type 1 and type 2 EC and 13 endometrial samples confirmed an altered abundance of MMP2. Our proteomics analysis identified the dysregulated ECM proteins involved in cancer growth. Our data can open the path to other studies for understanding the interaction among cancer cells and the rearrangement of the ECM.

FLOT1, stabilized by WTAP/IGF2BP2 mediated N6-methyladenosine modification, predicts poor prognosis and promotes growth and invasion in gliomas

The expression, function, and mechanism of FLOT1 (flotillin-1) remains unknown in gliomas. Here, the expression and clinical value of FLOT1 in gliomas was bioinformatically and experimentally analyzed via online omics data and local tissues. Moreover, the effects of FLOT1 depletion on cell proliferation and invasion were also detected. Besides, the underlying roles of N6-methyladenosine modification (m6A) in FLOT1 upregulation was further explored. The results demonstrated that FLOT1 was significantly upregulated in gliomas and positively correlated with advanced progression and poor prognosis of patients. FLOT1 silencing notably suppressed the cell proliferation and invasion in gliomas. The expression of WTAP and IGF2BP2was positively correlated with FLOT1 expression and served as the writer and reader of FLOT1 m6A, respectively, which stabilized FLOT1 mRNA and maintained its upregulation in gliomas. Lastly, ectopic expression of FLOT1 could notably restore the inhibitory effects caused by WTAP and IGF2BP2 depletion in glioma cells. Collectively, our results originally confirmed the upregulation and oncogenic roles of FLOT1, and revealed that WTAP/IGF2BP2 mediated m6A contributed to the upregulation of FLOT1 in gliomas, highlighting the promising application of WTAP/IGF2BP2/FLOT1 axis in target treatment of gliomas.

Flotillin-1 promotes progression and dampens chemosensitivity to cisplatin in gastric cancer via ERK and AKT signaling pathways

BACKGROUND

Several past studies have reported the overexpression of Flotillin-1 in a variety of cancer types. Cisplatin is a chemotherapeutic drug commonly used for cancer treatment. The present study investigated the role of Flotillin-1 in the progression of GC and assessed whether it assists in the chemical sensitization of GC cells toward cisplatin.

METHOD

The expression of Flotillin-1 was detected both in human gastric mucosal cells and GC cells. Next, siRNA and shRNA were used to construct a stable cell line expressing low levels of Flotillin-1. Furthermore, the Cell Counting Kit 8 (CCK-8), flow cytometry, and transwell assays were employed to detect the impact of Flotillin-1 on GC cells. In addition, a nude mouse model of human GC was used to verify the knockdown of Flotillin-1 to increase the sensitivity of GC cells to cisplatin.

RESULTS

Flotillin-1 was overexpressed in GC cells when compared to that in human gastric mucosal cells. The results for in vitro and vivo assays revealed that the knockdown of Flotillin-1 could significantly inhibit the proliferation of GC cells and increased the sensitivity of GC cells to cisplatin via the regulation of the protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) signaling pathway.

CONCLUSION

Flotillin-1 might be used as a molecular marker for GC diagnosis and could be explored as a potential new target for the treatment of GC.

Phosphoproteomics analysis of male and female Schistosoma mekongi adult worms

Schistosoma mekongi is one of the major causative agents of human schistosomiasis in Southeast Asia. Praziquantel is now the only drug available for treatment and there are serious concerns about parasite resistance to it. Therefore, a dataset of schistosome targets is necessary for drug development. Phosphorylation regulates signalling pathways to control cellular processes that are important for the parasite's growth and reproduction. Inhibition of key phosphoproteins may reduce the severity of schistosomiasis. In this research, we studied the phosphoproteomes of S. mekongi male and female adult worms by using computational and experimental approaches. Using a phosphoproteomics approach, we determined that 88 and 44 phosphoproteins were male- and female-biased, respectively. Immunohistochemistry using anti-phosphoserine antibodies demonstrated phosphorylation on the tegument and muscle of male S. mekongi worms and on the vitelline gland and gastrointestinal tract of female worms. This research revealed S. mekongi sex-dependent phosphoproteins. Our findings provide a better understanding of the role of phosphorylation in S. mekongi and could be integrated with information from other Schistosoma species to facilitate drug and vaccine development.

Clinical significance and comparison of flotillin 1 expression in left and right colon cancer

Flotillin 1 (FLOT1) is increasingly implicated in various types of cancer, and has been reported to influence tumorigenesis and cancer progression, leading to poor prognosis for survival time; however, its expression in colorectal cancer (CRC) and its influence on various clinicopathological parameters of this disease remain unknown. In the present study, FLOT1 expression and its effect on different clinicopathological parameters were assessed immunohistochemically and histologically in 81 CRC and 81 non-tumorous colon tissue samples. The immunohistochemical staining was scored semi-quantitatively. The association of FLOT1 expression with various parameters and its effect on overall survival time was also assessed. FLOT1 was upregulated in the CRC tissue, with increased expression in the right colon tissue samples compared with those of left colon. Increased FLOT1 expression in CRC tissue samples was associated with tumor volume, differentiation, tumor grade and poor overall survival time. In the right colon tissue samples in particular, there was a notable association with tumor volume and grade, indicating its effect on proliferation and tumor stage at this site. A multivariate Cox regression hazard analysis revealed that only tumor grade and differentiation were the independent predictors of overall survival time in patients with CRC. Together, the results of the present study suggest that FLOT1 serves important functions in the proliferation and progression of CRC, contributes to decreased survival time, and may serve as a novel therapeutic target for the treatment of CRC.

Genome-wide methylome and chromatin interactome identify abnormal enhancer to be risk factor of breast cancer

Enhancer is critical cis regulatory elements in gene expression. To understand whether and how the aberrant enhancer activation may contribute to cancer risk, the differentially methylated enhancers (eDMRs) in normal and malignant breast tissues were identified and analyzed. By incorporating genome-wide chromatin interaction, integrated analysis of eDMRs and target gene expression identified 1,272 enhancer-promoter pairs. Surprisingly, two functionally distinct groups of genes were identified in these pairs, one showing better correlation to enhancer methylation (eRGs) and the other showing better correlation to promoter methylation (pRGs), and the former group is functionally enriched with cancer related genes. Moreover, enhancer methylation based clustering of breast cancer samples is capable of discriminating basal breast cancer from other subtypes. By correlating enhancer methylation status to patient survival, 345 enhancers show the impact on the disease outcome and the majority of their target genes are important regulators of cell survival pathways including known cancer related genes. Together, these results suggest reactivation of enhancers in cancer cells has the add-on effect and contributes to cancer risk in combination.