Lei Zhan

NOD-like receptor family CARD domain-containing 5 (NLRC5) is a major transcriptional coactivator of MHC class I genes. NLRC5 is the largest member of the NLR family and contains three domains: an untypical caspase recruitment domain (uCARD), a central nucleotide-binding and oligomerization domain (NOD or NACHT), and a leucine-rich repeat (LRR) domain. The functional variability of NLRC5 has been attributed to its different domain interactions with specific ligands in different cell types. In this review, we address the molecular mechanisms and their implications in multiple microenvironments based on the different functional domains of NLRC5.

Endometriosis is well known as a chronic inflammatory disease. The development of endometriosis is heavily influenced by the estrogen receptor β (ERβ), while NOD-like receptors (NLRs) family CARD domain-containing 5 (NLRC5) exhibits anti-inflammatory properties during endometriosis. However, whether NLRC5-mediated anti-inflammation is involved in the ERβ-mediated endometriosis is still uncertain. This study aimed to assess that relation. Nine cases of eutopic endometrial tissue and ten cases of ectopic endometrial tissue were collected from patients with endometriosis, and endometrial samples from ten healthy fertile women were analyzed, and the expression levels of ERβ were quantified using immunohistochemistry (IHC). Subsequently, we constructed mouse model of endometriosis by intraperitoneal injection. We detected the expression of ERβ, NLRC5, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-10 and measured the volume of ectopic lesions in mice with endometriosis. In vitro, human endometrial stromal cells (hESCs) were transfected respectively with ERβ-overexpressing and NLRC5-overexpressing plasmids. We then assessed the expression of ERβ and NLRC5 using quantitative real-time PCR (qRT-PCR) and western blot analysis. Furthermore, we measured the concentrations of TNF-α, IL-6, and IL-10 in the cell culture supernatant through enzyme-linked immunosorbent assay (ELISA). Additionally, we evaluated the migration and invasion ability of hESCs using transwell and wound healing assays. Inhibition of NLRC5 expression promotes the development of ectopic lesions in mice with endometriosis, upregulates the expression of pro-inflammatory factors TNF-α and IL-6, and downregulates the expression of anti-inflammatory factor IL-10. The high expression of NLRC5 in endometriosis depended on the ERβ overexpression. And ERβ promoted the migration of hESCs partially depend on inflammatory microenvironment. Lastly, NLRC5 overexpression inhibited ERβ-mediated development and inflammatory response of endometriosis. Our results suggest that the innate immune molecule NLRC5-mediated anti-inflammation participates in ERβ-mediated endometriosis development, and partly clarifies the pathological mechanism of endometriosis, expanding our knowledge of the specific molecules related to the inflammatory response involved in endometriosis and potentially providing a new therapeutic target for endometriosis.

The innate immune molecule NLR family CARD domain-containing 5 (NLRC5) plays a significant role in endometrial carcinoma (EC) immunosurveillance. However, NLRC5 also plays a protumor role in EC cells. Mismatch repair gene deficiency (dMMR) can enable tumors to grow faster and also can exhibit high sensitivity to immune checkpoint inhibitors. In this study, we attempted to determine whether NLRC5-mediated protumor role in EC is via the regulation of dMMR. Our findings revealed that NLRC5 promoted the proliferation, migration, and invasion abilities of EC cells and induced the dMMR status of EC in vivo and in vitro. Furthermore, the mechanism underlying NLRC5 regulated dMMR was also verified. We first found NLRC5 could suppress nuclear factor-kappaB (NF-κB) pathway in EC cells. Then we validated that the positive effect of NLRC5 in dMMR was restricted when NF-κB was activated by lipopolysaccharides in NLRC5-overexpression EC cell lines. In conclusion, our present study confirmed the novel NLRC5/NF-κB/MMR regulatory mechanism of the protumor effect of NLRC5 on EC cells, thereby suggesting that the NLRC5-mediated protumor in EC was depend on the function of MMR.

BASP1 is a membrane‐bound protein that plays a promotional or inhibitory role in a variety of tumors; however, its role in gastric cancer (GC) and in the immune microenvironment has not been reported. The objectives of this study were to determine whether BASP1 is a valuable prognostic marker for GC and to explore its role in the immune microenvironment of GC. The expression level of BASP1 in GC was analyzed based on the TCGA dataset and further verified using GSE54129 and GSE161533 datasets, immunohistochemistry, and western blotting. The association between BASP1 and clinicopathological characteristics, as well as its predictive value, were examined using the STAD dataset. Cox regression analysis was performed to determine whether BASP1 can be used as an independent prognostic indicator for GC, and a nomogram was constructed to predict OS. The association between BASP1 and immune cell infiltration, immune checkpoints, and immune cell markers was confirmed by enrichment analysis, as well as analysis based on the TIMER and GEPIA databases. BASP1 was observed to be highly expressed in GC and was associated with a poor prognosis. The expression of BASP1 was positively correlated with the expression of immune checkpoints and immune cell markers, as well as immune cell infiltration. Thus, BASP1 may serve as a standalone prognostic indicator for GC. BASP1 is highly correlated with immune processes, and its expression is positively correlated with the degree of immune cell infiltration, immune checkpoints, and immune cell markers.

Endometriosis is closely associated with ectopic focal inflammation and immunosuppressive microenvironment. Multiple types of pattern recognition receptors (PRRs) are present in the innate immune system, which are able to detect pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) in both intracellular and external environments. However, the exact role of PRRs in endometriosis and the underlying molecular mechanism are unclear. PRRs are necessary for the innate immune system to identify and destroy invasive foreign infectious agents. Mammals mainly have two types of microbial recognition systems. The first one consists of the membrane-bound receptors, such as toll-like receptors (TLRs), which recognize extracellular microorganisms and activate intracellular signals to stimulate immune responses. The second one consists of the intracellular PRRs, including nod-like receptors (NLRs) and antiviral proteins retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (MDA-5) with helix enzyme domain. In this review, we mainly focus on the key role of PRRs in the pathological processes associated with endometriosis. PRRs recognize PAMPs and can distinguish pathogenic microorganisms from self, triggering receptor ligand reaction followed by the stimulation of host immune response. Activated immune response promotes the transmission of microbial infection signals to the cells. As endometriosis is characterized by dysregulated inflammation and immune response, PRRs may potentially be involved in the activation of endometriosis-associated inflammation and immune disorders. Toll-like receptor 2 (TLR2), toll-like receptor 3 (TLR3), toll-like receptor 4 (TLR4), nod-like receptor family caspase activation and recruitment domain (CARD) domain containing 5 (NLRC5), nod-like receptor family pyrin domain containing 3 (NLRP3), and c-type lectin receptors (CLRs) play essential roles in endometriosis development by regulating immune and inflammatory responses. Absent in melanoma 2 (AIM2)-like receptors (ALRs) and retinoic acid-inducible gene I-like receptors (RLRs) may be involved in the activation of endometriosis-associated immune and inflammation disorders. PRRs, especially TLRs, may serve as potential therapeutic targets for alleviating pain in endometriosis patients. PRRs and their ligands interact with the innate immune system to enhance inflammation in the stromal cells during endometriosis. Thus, targeting PRRs and their new synthetic ligands may provide new therapeutic options for treating endometriosis.

Context: Primary ovarian insufficiency (POI) is a heterogeneous disease with an unknown underlying trigger or root cause. Recently many studies evaluated noncoding RNAs (ncRNAs), especially microRNAs (miRNAs), long noncoding RNA (lncRNAs), circular RNAs (circRNAs), and small interfering RNAs (siRNAs) for their associations with POI. Evidence acquisition: In this review, we outline the biogenesis of various ncRNAs relevant to POI and summarize the evidence for their roles in the regulation of disease occurrence and progression. Articles from 2003 to 2022 were selected for relevance, validity, and quality from results obtained in PubMed and Google Scholar using the following search terms: noncoding RNAs; primary ovarian insufficiency; premature ovarian failure; noncoding RNAs and primary ovarian insufficiency/premature ovarian failure; miRNAs and primary ovarian insufficiency/premature ovarian failure; lncRNAs and primary ovarian insufficiency/premature ovarian failure; siRNAs and primary ovarian insufficiency/premature ovarian failure; circRNAs and primary ovarian insufficiency/premature ovarian failure; pathophysiology; and potential treatment. All articles were independently screened for eligibility by the authors. Evidence synthesis: This review summarizes the biological functions and synthesis of miRNAs, lncRNAs, siRNAs, and circRNAs in POI and discusses the findings of clinical and in vitro and in vivo studies. Although there is variability in the findings of individual studies, overall the available literature justifies the conclusion that dysregulated ncRNAs play significant roles in POI. Conclusion: The potential of ncRNAs in the treatment of POI requires further investigation, as ncRNAs derived from mesenchymal stem cell–secreted exosomes play pivotal roles and have considerable therapeutic potential in a multitude of diseases.

Uterine and ovarian cancers are the most common gynecologic cancers. N⁶⁻methyladenosine (m⁶A), an important internal RNA modification in higher eukaryotes, has recently become a hot topic in epigenetic studies. Numerous studies have revealed that the m⁶A-related regulatory factors regulate the occurrence and metastasis of tumors and drug resistance through various mechanisms. The m⁶A-related regulatory factors can also be used as therapeutic targets and biomarkers for the early diagnosis of cancers, including gynecologic cancers. This review discusses the role of m⁶A in gynecologic cancers and summarizes the recent advancements in m⁶A modification in gynecologic cancers to improve the understanding of the occurrence, diagnosis, treatment, and prognosis of gynecologic cancers.

Aims: The NOD-like receptor (NLR) family, caspase recruitment (CARD) domain containing 5 (NLRC5) was dysregulated in endometrial cancer (EC). However, the potential regulatory mechanisms of NLRC5 in EC remained unclear. We aimed to explore whether NLRC5 could regulate the programmed cell death protein ligand 1 (PD-L1) in EC. We also investigated the related molecular which led to the inactivation of NLRC5 in EC. Methods: The expressions of NLRC5 and PD-L1 in endometrium tissue microarray were detected by immunohistochemistry. Pearson’s correlation analysis was performed to detect the expression correlation between NLRC5 and PD-L1. Immunofluorescence staining, western blotting, and quantitative real-time PCR (qRT-PCR) were used to detect the role of NLRC5 in PD-L1 in EC cell lines. The somatic mutation in EC patients was detected by whole-exome sequencing (WGS). Results: NLRC5 was downregulated in the endometrium of EC patients when compared to those in the normal endometrium. The level of PD-L1 in the endometrium of EC patients was higher when compared to those in the normal endometrium. There was a negative expression correlation between NLRC5 and PD-L1. NLRC5 could promote the expression of PD-L1 in EC cell lines. The mutations of ANKRD20A2, C2orf42, ADGRB3, AVPR2, GOLGA6C, and IPPK may lead to the downregulation of NLRC5 in EC patients. Conclusion: NLRC5 could inhibit the activation of PD-L1 in EC. Mutations of ANKRD20A2, C2orf42, ADGRB3, AVPR2, GOLGA6C, and IPPK may lead to the downregulation of NLRC5 in EC patients. Future study should investigate the mechanism of NLRC5 in PD-L1, as well as the mechanism of ANKRD20A2, C2orf42, ADGRB3, AVPR2, GOLGA6C, and IPPK in NLRC5.