Transcription factor Tlx1 marks a subset of lymphoid tissue organizer-like mesenchymal progenitor cells in the neonatal spleen

High TLX1 Expression Correlates with Poor Prognosis and Immune Infiltrates in Patients with Lung Adenocarcinoma

BACKGROUND

To develop optimal personalized therapy for lung adenocarcinoma (LUAD), potential biomarkers associated with the prognosis are urgently needed. It is unclear what role T Cell Leukemia Homeobox 1 (TLX1) plays in LUAD.

OBJECTIVE

In this study, TLX1's relationship with LUAD was investigated using TCGA database analysis, bioinformatics analysis, and experimental validation.

METHODS

We examined the expression of TLX1 in pan cancer and LUAD, the relationship between TLX1 expression and clinical features, immune infiltration, its diagnostic and prognostic value, as well as TLX1 related pathways. The analysis included various statistical methods, including the Kaplan-Meier method, Cox regression analysis, GSEA, and immune infiltration analysis. TLX1 expression in LUAD cell lines was validated using qRT-PCR.

RESULT

In LUAD patients, high expression of TLX1 was associated with T stage (P<0.001). High TLX1 expression was associated with worse overall survival (OS) (HR: 1.57; 95% CI: 1.18-2.1; P=0.002). And TLX1 HR: 1.619; 95% CI: 1.012-2.590; P=0.044) was independently correlated with OS in LUAD patients. TLX1 expression was associated with the pathways, including Rho GTPase effectors, DNA repair, TCF dependent signaling in response to WNT, signaling by Nuclear Receptors, signaling by Notch, chromatin-modifying enzymes, ESR-mediated signaling, cellular senescence, and transcriptional regulation by Runx1. TLX1 expression was correlated with aDC, Tcm, and TReg cells. The expression of TLX1 was significantly increased in LUAD cells compared to BEAS-2B cells.

CONCLUSION

An association between high TLX1 expression and poor survival and immune infiltration was found in LUAD patients. There may be a potential role for TLX1 in diagnosis, prognosis, and immunotherapy for LUAD.

The spleen is the major site for the development and expansion of inhibitor producing-cells in hemophilia A mice upon FVIII infusion developing high-titer inhibitor

BACKGROUND

Hemophilia A (HA) is a hereditary bleeding disorder caused by defects in endogenous factor (F)VIII. Approximately 30 % of patients with severe HA treated with FVIII develop neutralizing antibodies (inhibitors) against FVIII, which render the therapy ineffective. The managements of HA patients with high-titter inhibitors are especially challenging. Therefore, it is important to understand the mechanism(s) of high-titer inhibitor development and dynamics of FVIII-specific plasma cells (FVIII-PCs).

AIMS

To identify the dynamics of FVIII-PCs and the lymphoid organs in which FVIII-PCs are localized during high-titer inhibitor formation.

METHODS AND RESULTS

When FVIII-KO mice were intravenously injected with recombinant (r)FVIII in combination with lipopolysaccharide (LPS), a marked enhancement of anti-FVIII antibody induction was observed with increasing FVIII-PCs, especially in the spleen. When splenectomized or congenitally asplenic FVIII-KO mice were treated with LPS + rFVIII, the serum inhibitor levels decreased by approximately 80 %. Furthermore, when splenocytes or bone marrow (BM) cells from inhibitor+ FVIII-KO mice treated with LPS + rFVIII were grafted into immune-deficient mice, anti-FVIII IgG was detected only in the serum of splenocyte-administered mice and FVIII-PCs were detected in the spleen but not in the BM. In addition, when splenocytes from inhibitor+ FVIII-KO mice were grafted into splenectomized immuno-deficient mice, inhibitor levels were significantly reduced in the serum.

CONCLUSION

The spleen is the major site responsible for the expansion and retention of FVIII-PCs in the presence of high-titer inhibitors.

Dendritic cell vaccines targeting tumor blood vessel antigens in combination with dasatinib induce therapeutic immune responses in patients with checkpoint-refractory advanced melanoma

Background

A first-in-human, randomized pilot phase II clinical trial combining vaccines targeting overexpressed, non-mutated tumor blood vessel antigens (TBVA) and tyrosine kinase inhibitor dasatinib was conducted in human leukocyte antigen (HLA)-A2⁺ patients with advanced melanoma.

Methods

Patient monocyte-derived type-1-polarized dendritic cells were loaded with HLA-A2-presented peptides derived from TBVA (DLK1, EphA2, HBB, NRP1, RGS5, TEM1) and injected intradermally as a vaccine into the upper extremities every other week. Patients were randomized into one of two treatment arms receiving oral dasatinib (70 mg two times per day) beginning in week 5 (Arm A) or in week 1 (Arm B). Trial endpoints included T cell response to vaccine peptides (interferon-γ enzyme-linked immunosorbent spot), objective clinical response (Response Evaluation Criteria in Solid Tumors V.1.1) and exploratory tumor, blood and serum profiling of immune-associated genes/proteins.

Results

Sixteen patients with advanced-stage cutaneous (n=10), mucosal (n=1) or uveal (n=5) melanoma were accrued, 15 of whom had previously progressed on programmed cell death protein 1 (PD-1) blockade. Of 13 evaluable patients, 6 patients developed specific peripheral blood T cell responses against ≥3 vaccine-associated peptides, with further evidence of epitope spreading. All six patients with specific CD8⁺ T cell response to vaccine-targeted antigens exhibited evidence of T cell receptor (TCR) convergence in association with preferred clinical outcomes (four partial response and two stabilization of disease (SD)). Seven patients failed to respond to vaccination (one SD and six progressive disease). Patients in Arm B (immediate dasatinib) outperformed those in Arm A (delayed dasatinib) for immune response rate (IRR; 66.7% vs 28.6%), objective response rate (ORR) (66.7% vs 0%), overall survival (median 15.45 vs 3.47 months; p=0.0086) and progression-free survival (median 7.87 vs 1.97 months; p=0.063). IRR (80% vs 25%) and ORR (60% vs 12.5%) was greater for females versus male patients. Tumors in patients exhibiting response to treatment displayed (1) evidence of innate and adaptive immune-mediated inflammation and TCR convergence at baseline, (2) on-treatment transcriptional changes associated with reduced hypoxia/acidosis/glycolysis, and (3) increased inflammatory immune cell infiltration and tertiary lymphoid structure neogenesis.

Conclusions

Combined vaccination against TBVA plus dasatinib was safe and resulted in coordinating immunologic and/or objective clinical responses in 6/13 (46%) evaluable patients with melanoma, particularly those initiating treatment with both agents.

Trial registration number

NCT01876212.

Fibroblasts as confederates of the immune system

Fibroblastic stromal cells are as diverse, in origin and function, as the niches they fashion in the mammalian body. This cellular variety impacts the spectrum of responses elicited by the immune system. Fibroblast influence on the immune system keeps evolving our perspective on fibroblast roles and functions beyond just a passive structural part of organs. This review discusses the foundations of fibroblastic stromal-immune crosstalk, under the scope of stromal heterogeneity as a basis for tissue-specific tutoring of the immune system. Focusing on the skin as a relevant immunological organ, we detail the complex interactions between distinct fibroblast populations and immune cells that occur during homeostasis, injury repair, scarring, and disease. We further review the relevance of fibroblastic stromal cell heterogeneity and how this heterogeneity is central to regulate the immune system from its inception during embryonic development into adulthood.

Hox-Positive Adult Mesenchymal Stromal Cells: Beyond Positional Identity

Homeotic genes (Hox) are universal regulators of the body patterning process in embryogenesis of metazoans. The Hox gene expression pattern (Hox code) retains in adult tissues and serves as a cellular positional identity marker. Despite previously existing notions that the Hox code is inherent in all stroma mesenchymal cells as a whole, recent studies have shown that the Hox code may be an attribute of a distinct subpopulation of adult resident mesenchymal stromal cells (MSC). Recent evidence allows suggesting a "non-canonical" role for Hox gene expression which is associated with renewal and regeneration in postnatal organs after damage. In tissues with high regenerative capacity, it has been shown that a special cell population is critical for these processes, a distinctive feature of which is the persistent expression of tissue-specific Hox genes. We believe that in the postnatal period Hox-positive subpopulation of resident MSC may serve as a unique regenerative reserve. These cells coordinate creation and maintenance of the correct structure of the stroma through a tissue-specific combination of mechanisms. In this article, we summarize data on the role of resident MSC with a tissue-specific pattern of Hox gene expression as regulators of correct tissue reconstruction after injury.

Long Non-Coding RNA BCAR4 Binds to miR-644a and Targets TLX1 to Promote the Progression of Bladder Cancer

Background

Bladder cancer is a serious threat to human health. It is meaningful to study the pathogenesis of bladder cancer. Long non-coding RNAs (lncRNAs) are reported to promote or inhibit bladder cancer development. However, the role of lncRNA BCAR4 in the regulation of bladder cancer remains unclear.

Purpose

This study was to explore the role of lncRNA BCAR4 in the progression of bladder cancer cell.

Methods

RT-PCR was used to examine the expression of BCAR4 and miR-644a. CCK8 assay, colony formation assay, Transwell assay were used to detect the progression of bladder cancer cells after transfecting of indicated plasmids.

Results

The expression of BCAR4 was higher in bladder cancer cell lines than normal urothelial cell line. Moreover, the expression of BCAR4 was associated with the advanced stage and metastasis of bladder cancer. Through knockdown of BCAR4, we discovered that knockdown of BCAR4 significantly decreased the proliferation, migration and invasive abilities of bladder cancer cells. Mechanically, we showed that BCAR4 can bind to miR-644a directly and targets TLX1. Moreover, we also showed that miR-644a was also highly expressed in bladder cancer cells and inhibition of miR-644a or overexpression of TLX1 can increased the migration abilities of bladder cancer caused by knockdown of BCAR4.

Conclusion

We showed that BCAR4 sponged miR-644a to modulate the expression of TLX1 and promote bladder cancer development.