Spatio-temporal expression patterns of glycine-rich beta proteins and cysteine-rich beta proteins in setae development of Gekko japonicus.

BACKGROUND: Setae on the pad lamellae of the Japanese gecko Gekko japonicus (Schlegel, 1836), a vital epidermal derivative, are primarily composed of cornified beta-proteins (CBPs) and play a pivotal role in adhesion and climbing. The amino acid composition of CBPs might be a determining factor influencing their functional properties. However, the molecular mechanisms governed by CBP genes with diverse amino acid compositions in setae development remain unexplored. RESULTS: Based on RNA-seq analyses, this study confirmed that all G. japonicus CBPs (GjCBPs) are involved in setae formation. Cysteine-rich CBPs encoding genes (ge-cprp-17 to ge-cprp-26) and glycine-rich CBPs encoding genes (ge-gprp-17 to ge-gprp-22) were haphazardly selected, with quantitative real-time PCR revealing their expression patterns in embryonic pad lamellae and dorsal epidermis. It is inferred that glycine-rich CBPs are integral to the formation of both dorsal scales and lamellar setae, cysteine-rich CBPs are primarily associated with setae development. Additionally, fluorescence in situ hybridization revealed spatiotemporal differences in the expression of a glycine-rich CBP encoding gene (ge-gprp-19) and a cysteine-rich CBP encoding gene (ge-cprp-17) during dorsal scales and/or lamellar development. CONCLUSIONS: All 66 CBPs are involved in the formation of setae. Glycine-rich CBPs hold a significant role in the development of dorsal scales and lamellar setae, whereas most cysteine-rich CBPs appear to be essential components of G. japonicus setae. Even GjCBPs with similar amino acid compositions may play diverse functions. The clear spatio-temporal expression differences between the glycine-rich and cysteine-rich CBP encoding genes during epidermal scale and/or setae formation were observed. Embryonic developmental stages 39 to 42 emerged as crucial phases for setae development. These findings lay the groundwork for deeper investigation into the function of GjCBPs in the development of G. japonicus setae.

Combining bulk and scRNA-seq to explore the molecular mechanisms governing the distinct efferocytosis activities of a macrophage subpopulation in PDAC.

Pancreatic ductal adenocarcinoma (PDAC), a very aggressive tumour, is currently the third leading cause of cancer-related deaths. Unfortunately, many patients face the issue of inoperability at the diagnostic phase leading to a quite dismal prognosis. The onset of metastatic processes has a crucial role in the elevated mortality rates linked to PDAC. Individuals with metastatic advances receive only palliative therapy and have a grim prognosis. It is essential to carefully analyse the intricacies of the metastatic process to enhance the prognosis for individuals with PDAC. Malignancy development is greatly impacted by the process of macrophage efferocytosis. Our current knowledge about the complete range of macrophage efferocytosis activities in PDAC and their intricate interactions with tumour cells is still restricted. This work aims to resolve communication gaps and pinpoint the essential transcription factor that is vital in the immunological response of macrophage populations. We analysed eight PDAC tissue samples sourced from the gene expression omnibus. We utilized several software packages such as Seurat, DoubletFinder, Harmony, Pi, GSVA, CellChat and Monocle from R software together with pySCENIC from Python, to analyse the single-cell RNA sequencing (scRNA-seq) data collected from the PDAC samples. This study involved the analysis of a comprehensive sample of 22,124 cells, which were classified into distinct cell types. These cell types encompassed endothelial and epithelial cells, PDAC cells, as well as various immune cells, including CD4+ T cells, CD8+ T cells, NK cells, B cells, plasma cells, mast cells, monocytes, DC cells and different subtypes of macrophages, namely C0 macrophage TGM2+, C1 macrophage PFN1+, C2 macrophage GAS6+ and C3 macrophage APOC3+. The differentiation between tumour cells and epithelial cells was achieved by the implementation of CopyKat analysis, resulting in the detection and categorization of 1941 PDAC cells. The amplification/deletion patterns observed in PDAC cells on many chromosomes differ significantly from those observed in epithelial cells. The study of Pseudotime Trajectories demonstrated that the C0 macrophage subtype expressing TGM2+ had the lowest level of differentiation. Additionally, the examination of gene set scores related to efferocytosis suggested that this subtype displayed higher activity during the efferocytosis process compared to other subtypes. The most active transcription factors for each macrophage subtype were identified as BACH1, NFE2, TEAD4 and ARID3A. In conclusion, the examination of human PDAC tissue samples using immunofluorescence analysis demonstrated the co-localization of CD68 and CD11b within regions exhibiting the presence of keratin (KRT) and alpha-smooth muscle actin (α-SMA). This observation implies a spatial association between macrophages, fibroblasts, and epithelial cells. There is variation in the expression of efferocytosis-associated genes between C0 macrophage TGM2+ and other macrophage cell types. This observation implies that the diversity of macrophage cells might potentially influence the metastatic advancement of PDAC. Moreover, the central transcription factor of different macrophage subtypes offers a promising opportunity for targeted immunotherapy in the treatment of PDAC.

SIVA-1 enhances acquired chemotherapeutic drug resistance of gastric cancer in vivo by regulating the ARF/MDM2/p53 pathway.

SIVA-1 has been shown to affect apoptotic processes in various different cell lines, and SIVA-1 significantly contributes to the decreased responsiveness of cancer cells to some chemotherapy agents. However, whether SIVA-1 has potential application in gastric cancer remains unknown. Therefore, the objective of this investigation was to clarify the distinct function of SIVA-1 in chemotherapeutic drug resistance within a living murine model with gastric malignancy, and initially elucidate the underlying mechanisms. In an established multidrug-resistant gastric cancer xenograft mouse model, lentivirus, named Lv-SIVA-1, was injected into xenograft tumors, and increased the mRNA and protein expression of endogenous SIVA-1 in tumors. Immunohistochemical assays of xenograft tumor showed that SIVA-1 was significantly upregulated, and the protein expression levels of SIVA-1 were highly increased, as detected by Western blotting. In addition, we detected the role of SIVA-1 in cell proliferation and cell apoptosis in gastric cancer cells by TUNEL and found that SIVA-1 decreased tumor cell apoptosis and promoted tumor growth in vivo. Using a TMT assay between tumor tissues of experimental and control groups, differentially expressed proteins were examined and three potential biomarkers of multidrug resistance (ARF, MDM2, and p53) were screened. We further investigated the molecular mechanism by which SIVA-1 played an efficient role against chemotherapies and found that overexpressed SIVA-1 leads to increased ARF and MDM2 expression and suppressed expression of p53 in tumor tissue. In conclusion, SIVA-1 plays a significant role in the multidrug resistance of gastric tumors. In addition, overexpressed SIVA-1 positively regulates cell proliferation, adjusts cycle progression, and reduces the response to drug treatment for gastric cancer in an ARF/MDM2/p53-dependent manner. This novel research provides a basis for chemical management of gastric cancer through regulation of SIVA-1 expression.