Tumor Cell-Intrinsic BTLA Receptor Inhibits the Proliferation of Tumor Cells via ERK1/2.

B and T lymphocyte attenuator (BTLA) is an immune checkpoint molecule that mediates the escape of tumor cells from immunosurveillance. Consequently, BTLA and its ligand herpesvirus entry mediator (HVEM) are potentially immunotherapeutic targets. However, the potential effects of BTLA on tumor cells remain incompletely unknown. Here, we show that BTLA is expressed across a broad range of tumor cells. The depletion of BTLA or HVEM promotes cell proliferation and colony formation, which is reversed by the overexpression of BTLA in BTLA knockout cells. In contrast, overexpression of BTLA or HVEM inhibits tumor cell proliferation and colony formation. Furthermore, the proliferation of a subpopulation with high BTLA was also significantly slower than that of the low BTLA subpopulation. Mechanistically, the coordination of BTLA and HVEM inhibits its major downstream extracellular regulated protein kinase (ERK1/2) signaling pathway, thus preventing tumor cell growth. This study demonstrates that tumor cell-intrinsic BTLA/HVEM is a potential tumor suppressor and is likely to have a potential antagonist for immunotherapy, thus representing a potential biomarker for the optimal cancer immunotherapeutic treatment.

[A multi-omics study on NKX3.1-related node genes in prostate cancer].

Objective: The NKX3.1 homeobox gene is closely associated with the development and progression of prostate cancer. This study was to explore NKX3.1-related down-stream node genes and their possible regulating mechanisms in prostate cancer. Methods: By multi-omics analysis of the TCGA data on prostate cancer,we screened 5 node genes in the down-stream signaling pathways that were possibly related to NKX3.1.We achieved the overexpression of NKX3.1 in prostate cancer by transfecting the prostate cancer PC-3 cell lines with the NKX3.1 expression vector and determined the expression levels of the node genes by real-time PCR. Results: Based on the results of multi-omics analysis,MAZ,LPAR3,TUBB2A,CAMKK2 and CPT1B were identified as the node genes involved in the NKX3.1-related signaling pathways in prostate cancer. The NKX3.1 overexpression experiments showed that the CAMKK2 and CPT1B genes were up-regulated 3. 439 and 4. 641 times respectively and the MAZ gene down-regulated 5.236 times in the prostate cancer PC-3 cells with the overexpression of NKX3.1. Conclusion: NKX3.1 may suppress the development and progression of prostate cancer by down-regulating the expression of MAZ and up-regulating those of CAMKK2 and CPT1B,and it may also be involved in the regulation of the metabolic process of prostate cancer through the CAMKK2 down-stream signaling pathway and CPT1B.