Neuroinflammatory Profiling in SIV-Infected Chinese-Origin Rhesus Macaques on Antiretroviral Therapy

The central nervous system (CNS) HIV reservoir is an obstacle to achieving an HIV cure. The basal ganglia harbor a higher frequency of SIV than other brain regions in the SIV-infected rhesus macaques of Chinese-origin (chRMs) even on suppressive combination antiretroviral therapy (ART). Since residual HIV/SIV reservoir is associated with inflammation, we characterized the neuroinflammation by gene expression and systemic levels of inflammatory molecules in healthy controls and SIV-infected chRMs with or without ART. CCL2, IL-6, and IFN-γ were significantly reduced in the cerebrospinal fluid (CSF) of animals receiving ART. Moreover, there was a correlation between levels of CCL2 in plasma and CSF, suggesting the potential use of plasma CCL2 as a neuroinflammation biomarker. With higher SIV frequency, the basal ganglia of untreated SIV-infected chRMs showed an upregulation of secreted phosphoprotein 1 (SPP1), which could be an indicator of ongoing neuroinflammation. While ART greatly reduced neuroinflammation in general, proinflammatory genes, such as IL-9, were still significantly upregulated. These results expand our understanding of neuroinflammation and signaling in SIV-infected chRMs on ART, an excellent model to study HIV/SIV persistence in the CNS.

Higher Expression of SPP1 Predicts Poorer Survival Outcomes in Head and Neck Cancer

Secreted phosphoprotein 1 (SPP1) participated in various biological processes in many cancers, including immune response, tumor progression, and prognosis. However, SPP1 in head and neck squamous cell carcinoma (HNSCC) remains unknown. Clinical-genetic data of HNSCC were obtained from The Cancer Genome Atlas (TCGA) database. The differential expression of SPP1 in HNSCC tissues and adjacent normal tissues was quantified by bioinformatics methods and verified by western blot and other differential biological methods. We concluded that SPP1 is significantly upregulated in tumor tissues and can become a prognostic biomarker for HNSCC.

SPP1 is a Prognostic Related Biomarker and Correlated with Tumor-Infiltrating Immune Cells in Hepatocellular Carcinoma

Background: Secreted phosphoprotein 1 (SPP1) functions as a tumor promoter in varies tumors, but little is known whether it is an actual player on driving immune infiltration in hepatocellular carcinoma. Methods: In this study, we identified the expression of SPP1 by Oncomine, GEPIA and TIMER databases, and assessed SPP1 immumohistochemical staining analysis by The HPA database. We evaluated the clinical outcomes between SPP1 expression and hepatocellular carcinoma patients via Kaplan-Meier Plotter. We also tested the relationship between SPP1 and critical oncogenes by TIMER and GEPIA databases. Then we explored immune infiltration analyses using TIMER and TISIDB datasets. In addition, we performed functional enrichment analyses with Metascape and GeneMANIA databases. Results: We found that SPP1 overexpressed in hepatocellular carcinoma tissues and high SPP1 expression was correlated with shorter OS and PFS survivals in hepatocellular carcinoma patients. SPP1 expression is positive correlation with critical oncogenes related stemness associated genes, cell cycle and proliferation, therapeutic resistance, metastasis, and tumor angiogenesis in hepatocellular carcinoma. Importantly, SPP1 expression was positively correlated with infiltrating levels of CD4+ T cells, CD8+ T cells, macrophages, neutrophils, and dendritic cells. Furthermore, SPP1 expression showed strong correlations with diverse immune hallmark sets in hepatocellular carcinoma. Notably, functional enrichment analysis suggested that SPP1 strong related with immune response. Conclusions: These findings imply that SPP1 is correlated with prognosis and immune cell infiltrating, offering a new potential immunotherapeutic target in hepatocellular carcinoma.

Complex Interactions Between Human Immunodeficiency Virus Type-1, Sex, and Osteopontin Influence Viral Replication and Leukocyte Proportions in Tissues

Evidence suggesting that HIV pathogenesis differs by sex, a variable known to influence the extent and breadth of immune responses in health and disease continues to accumulate. Host factors that promote or inhibit HIV replication may do so in a way that varies by sex. Prior studies using cultured human macrophages demonstrated that osteopontin (OPN)/secreted phosphoprotein-1 (SPP1) stimulates HIV replication. To test whether OPN has the same positive impact on virus replication at the level of tissues, we used a humanized mice model of low-level chronic HIV infection and in which OPN RNA and protein expression was inhibited with targeted aptamers. Interestingly, 4 months after infection when there were no significant differences in HIV viral load in plasma between groups however in contrast, in the spleen, lung, and liver the tissue burden of HIV RNA, as well as the proportion of leukocytes in female and male mice differed depending on whether OPN was expressed or not. The findings collectively demonstrate the potential for complex interactions between host factors like OPN and sex to influence different facets of HIV tissue-level pathogenesis.

Hepatic mRNA Expression Levels of the Oncogenes Alpha-Fetoprotein and Osteopontin as Diagnostics for Liver Cancer in a Murine Model of Diet-Induced Non-Alcoholic Steatohepatitis

Non-alcoholic steatohepatitis (NASH) is associated with an increased risk of hepatocellular carcinoma (HCC). Expression levels of hepatic oncogenes, alpha-fetoprotein (afp) and osteopontin (opn)/secreted phosphoprotein 1 (spp1), were investigated using a model of diet-induced NASH. Mice were randomized to a standard diet or a fast-food diet (FFD) for 17 months. Livers from the FFD cohort exhibited hallmark characteristics of NASH with liver fibrosis, with a subset of animals exhibiting HCC. Expression levels of hepatic afp and opn/spp1 were elevated ~2.5 and ~5-fold, respectively, in the FFD cohort. Hepatic opn/spp1 exhibited a direct (r = 0.65) and significant (p < 0.01) correlation with liver hydroxyproline content. Receiver operating characteristic (ROC) curve analysis for hepatic afp, as a diagnostic for HCC, returned an area under (AU) ROC 0.84, a sensitivity of 87.5%, a specificity of 77% and a threshold of >1.05-fold change in mRNA level. The use of hepatic opn/ssp1 as a diagnostic for HCC returned an AUROC 0.88, a sensitivity of 83.3%, a specificity of 86.7% and a threshold of >2.4-fold change in mRNA level. These data point to a transformation of NASH to an oncotype with hepatic oncogene levels as a diagnostic for NASH.

Calcium silicate-based cements cause environmental stiffness and show diverse potential to induce osteogenesis in human osteoblastic cells

Calcium silicate-based cements differ markedly in their radiopacifiers and the presence of calcium sulfate, aluminates, carbonates and other components that can affect their biological properties. This study aimed to compare the biological properties of six calcium silicate cements in human osteoblastic cell culture (Saos-2 cells): Bio-C Repair (Bio-C), PBS HP (PBS-HP), Biodentine (Biodentine), MTA Repair HP (MTA-HP), NeoMTA Plus (NeoMTA-P), and ProRoot MTA (ProRoot). After exposure to these materials, the cells were analyzed by MTT, wound healing, cell migration, and alkaline phosphatase activity (ALP) assays, real-time PCR (qPCR) analysis of the osteogenesis markers (osteocalcin or bone gamma-carboxyglutamate protein, BGLAP; alkaline phosphatase, ALPL; bone sialoprotein or secreted phosphoprotein 1, BNSP), and alizarin red staining (ARS). Curiously, the migration rates were low 24–48 h after exposure to the materials, despite the cells showing ideal rates of viability. The advanced and intermediate cell differentiation markers BGLAP and BNSP were overexpressed in the Bio-C, MTA-HP, and ProRoot groups. Only the Biodentine group showed ALPL overexpression, a marker of initial differentiation. However, the enzymatic activity was high in all groups except Biodentine. The mineralization area was significantly large in the NeoMTA-P, ProRoot, PBS-HP, MTA-HP, and Bio-C groups. The results showed that cellular environmental stiffness, which impairs cell mobility and diverse patterns of osteogenesis marker expression, is a consequence of cement exposure. Environmental stiffness indicates chemical and physical stimuli in the microenvironment; for instance, the release of cement compounds contributes to calcium phosphate matrix formation with diverse stiffnesses, which could be essential or detrimental for the migration and differentiation of osteoblastic cells. Cells exposed to Bio-C, PBS-HP, ProRoot, NeoMTA-P, and MTA-HP seemed to enter the advanced or intermediate differentiation phases early, which is indicative of the diverse potential of cements to induce osteogenesis. Cements that quickly stimulate osteoblast differentiation may be ideal for reparative and regenerative purposes since they promptly lead to dentin or bone deposition.

SPP1 expression in the mouse uterus and placenta: Implications for implantation

Secreted phosphoprotein 1 [SPP1, also known as osteopontin (OPN)] binds integrins to mediate cell–cell and cell-extracellular matrix communication to promote cell adhesion, migration, and differentiation. Considerable evidence links SPP1 to pregnancy in several species. Current evidence suggests that SPP1 is involved in implantation and placentation in mice, but in vivo localization of SPP1 and in vivo mechanistic studies to substantiate these roles are incomplete and contradictory. We localized Spp1 mRNA and protein in the endometrium and placenta of mice throughout gestation, and utilized delayed implantation of mouse blastocysts to link SPP1 expression to the implantation chamber. Spp1 mRNA and protein localized to the endometrial luminal (LE), but not glandular epithelia (GE) in interimplantation regions of the uterus throughout gestation. Spp1 mRNA and protein also localized to uterine naturel killer (uNK) cells of the decidua. Within the implantation chamber, Spp1 mRNA localized only to intermittent LE cells, and to the inner cell mass. SPP1 protein localized to intermittent trophoblast cells, and to the parietal endoderm. These results suggest that SPP1: 1) is secreted by the LE at interimplantation sites for closure of the uterine lumen to form the implantation chamber; 2) is secreted by LE adjacent to the attaching trophoblast cells for attachment and invasion of the blastocyst; and 3) is not a component of histotroph secreted from the GE, but is secreted from uNK cells in the decidua to increase angiogenesis within the decidua to augment hemotrophic support of embryonic/fetal development of the conceptus.

SPP1 is a Prognostic Related Biomarker and Correlated With Tumor-Infiltrating Immune Cells in Ovarian Cancer

Background: Secreted phosphoprotein 1 (SPP1) plays a vital role in tumor progression of some cancer types, but little is known whether it is a bystander or an actual player on driving immune infiltration in ovarian cancer.Methods: In this study, the expression of SPP1 was identified by Oncomine, GEPIA and TIMER databases, and SPP1 immumohistochemical staining analysis was assessed by The HPA database. The clinical outcomes between SPP1 expression and ovarian cancer patients were evaluated via Kaplan-Meier Plotter and PrognoScan dataset. Immune infiltration analyses were explored using TIMER and TISIDB dataset. In addition, Functional enrichment analyses were performed with Metascape and GeneMANIA database.Results: SPP1 was found overexpressed in ovarian tumor tissues and high SPP1 expression was correlated with shorter OS and PFS survivals. Particularly, elevated SPP1 expression was significantly associated with stage III ovarian cancer. Notably, SPP1 expression was positively correlated with infiltrating levels of CD4+ T cells, CD8+ T cells, macrophages, neutrophils, and dendritic cells. Furthermore, SPP1 expression showed strong correlations with diverse immune hallmark sets in ovarian cancer. Of particular importance, functional enrichment analysis suggested that SPP1 strong related with immune response.Conclusions: These findings imply that SPP1 is correlated with prognosis and immune cell infiltrating, offering a new potential immunotherapeutic target in ovarian cancer.Trial registration: Not applicable.