The immune-suppressive landscape in lepromatous leprosy revealed by single-cell RNA sequencing

Lepromatous leprosy (L-LEP), caused by the massive proliferation of Mycobacterium leprae primarily in macrophages, is an ideal disease model for investigating the molecular mechanism of intracellular bacteria evading or modulating host immune response. Here, we performed single-cell RNA sequencing of both skin biopsies and peripheral blood mononuclear cells (PBMCs) of L-LEP patients and healthy controls. In L-LEP lesions, we revealed remarkable upregulation of APOE expression that showed a negative correlation with the major histocompatibility complex II gene HLA-DQB2 and MIF, which encodes a pro-inflammatory and anti-microbial cytokine, in the subset of macrophages exhibiting a high expression level of LIPA. The exhaustion of CD8+ T cells featured by the high expression of TIGIT and LAG3 in L-LEP lesions was demonstrated. Moreover, remarkable enhancement of inhibitory immune receptors mediated crosstalk between skin immune cells was observed in L-LEP lesions. For PBMCs, a high expression level of APOE in the HLA-DRhighFBP1high monocyte subset and the expansion of regulatory T cells were found to be associated with L-LEP. These findings revealed the primary suppressive landscape in the L-LEP patients, providing potential targets for the intervention of intracellular bacteria caused persistent infections.

STEAP3 promotes cancer cell proliferation by facilitating nuclear trafficking of EGFR to enhance RAC1-ERK-STAT3 signaling in hepatocellular carcinoma

STEAP3 (Six-transmembrane epithelial antigen of the prostate 3, TSAP6, dudulin-2) has been reported to be involved in tumor progression in human malignancies. Nevertheless, how it participates in the progression of human cancers, especially HCC, is still unknown. In the present study, we found that STEAP3 was aberrantly overexpressed in the nuclei of HCC cells. In a large cohort of clinical HCC tissues, high expression level of nuclear STEAP3 was positively associated with tumor differentiation and poor prognosis (p < 0.001), and it was an independent prognostic factor for HCC patients. In HCC cell lines, nuclear expression of STEAP3 significantly promoted HCC cells proliferation by promoting stemness phenotype and cell cycle progression via RAC1-ERK-STAT3 and RAC1-JNK-STAT6 signaling axes. Through upregulating the expression and nuclear trafficking of EGFR, STEAP3 participated in regulating EGFR-mediated STAT3 transactivity in a manner of positive feedback. In summary, our findings support that nuclear expression of STEAP3 plays a critical oncogenic role in the progression of HCC via modulation on EGFR and intracellular signaling, and it could be a candidate for prognostic marker and therapeutic target in HCC.

Histone demethylase KDM4D inhibition suppresses renal cancer progression and angiogenesis through JAG1 signaling

Kidney cancer, especially clear cell renal cell carcinoma (ccRCC), is one of the representative genitourinary tumors. Investigation of underlying mechanisms of ccRCC development is crucial for patient management. Histone demethylase KDM4D has been reported to be responsible for development of a variety of cancers. However, the role of KDM4D in ccRCC progression is poorly understood. In our study, we performed immunohistochemistry analysis of tissue microarrays first, and results showed that high expression level of KDM4D is connected with advanced Fuhrman grade (p = 0.0118) and lower overall survival (p = 0.0020). Then, we revealed that KDM4D can prompt ccRCC development by interacting with genes related to vessel morphogenesis. Finally, we disclosed that KDM4D directly interacts with JAG1 promoter and advances tumor angiogenesis by upregulating VEGFR-3 and antagonizing notch signaling. The results of our study indicate that KDM4D would be a potential prognostic marker and therapeutic target for ccRCC patients.

MCUR1 Promotes Osteosarcoma Cell Growth Through AKT/p53 Pathway

Background: Osteosarcoma (OS) is one of the most aggressive malignant bone tumor worldwide. This study focuses on investigating the mechanism underlying the mitochondrial calcium uniporter regulator 1 (MCUR1)-mediated osteosarcoma (OS) cell growth. Methods: A total of 49 patients diagnosed as OS in our hospital were included in the current study. The expression of MCUR1 in human OS tissues and various OS cell lines was detected by immunohistochemical staining (IHC) and western blot analysis, respectively. The effect of MCUR1 on AKT/p53 pathway and its correlation with miR-506-3p were investigated by a series of experiments including MTS, QRT-PCR, Western blot and IHC. Results: Our data showed that MCUR1 was highly overexpressed in OS tumor tissues compared with the para-carcinoma tissues (P<0.01). The Kaplan-Meier analysis showed that high expression level of MCUR1 was linked with poor prognosis of OS patients. Additionally, knockdown of MCUR1 enhanced OS cell apoptosis and decreased the growth of OS cells compared with the corresponding controls (P<0.05). Meanwhile, the expression level of p-AKT was decreased, whereas the protein expression level of p53 was increased in OS cells with MCUR1 downregulation. We also found that the IHC scores of MCUR1 were inversely correlated with that of p53 (r = -0.304, P=0.034). Likewise, the expression of MCUR1 and miR-506-3p in OS tissues were also inversely correlated (r=-0.304, P=0.034). Conclusions: MCUR1 is overexpressed in OS cells and its expression is regulated by miR-506-3p. MCUR1 facilitates the progression of OS through activating AKT/p53 pathway. The data in the current study suggests that MCUR1 may serve as a new target for the diagnosis and treatment of OS.

Artificial introns for effective expression of transgenes in mammalian cells

Introns are widely used in the assembly of genetic constructions expressing transgenic proteins in eukaryotic cells for the enhancement of this expression. However, the choice of introns that can be applied for such purposes is limited by the excessively large size of the majority of natural introns (several thousand nucleotides) and therefore they cannot be cloned in a genetic construction. With the help of site-directed mutagenesis we have generated a library of short (99 nucleotides long) introns. The efficiency of these introns in the enhancement of gene expression was analyzed. As a result, a set of 12 introns was selected. The generated intros can be used for genetic constructions with high expression level of recombinant proteins.

Comparison of time to failure of pembrolizumab plus chemotherapy versus pembrolizumab monotherapy: a consecutive analysis of patients having NSCLC with high PD-L1 expression

Introduction There are two treatment strategies for non-small cell lung cancer (NSCLC) exhibiting a high expression level of programmed death-ligand 1 (tumor proportion score ≥ 50%): pembrolizumab plus chemotherapy and monotherapy. We retrospectively compared their efficacy and safety. Materials and methods We reviewed the efficacy and safety of first-line pembrolizumab-containing regimens administered between 2017 and 2020 to consecutive patients. The patients were divided into a pembrolizumab plus chemotherapy group (Combo group) or monotherapy group (Mono group). To compare the efficacy, we monitored the time to failure of strategy (TFS) defined as the time from the start of treatment to the occurrence of one of the following events: the addition of any drug not included in the primary strategy, progression of cancer after complete therapy, progression and no subsequent therapy, or death, whichever occurred first. We used the propensity score matching (PSM) to reduce the bias. Results A total of 126 patients were identified (89 in the Mono group and 37 in the Combo group). PSM matched 36 individuals from each of the two groups. The overall response rate and median progression-free survival of the Combo group were better than those of the Mono group. However, the median TFS was almost the same (11.3 months vs. 14.9 months; hazard ratio 1.40 [95% confidence interval 0.62–3.15]). The frequency of all serious adverse effects was higher in the Combo group than in the Mono group. Discussion Due to similar efficacy in TFS, both pembrolizumab plus chemotherapy and monotherapy are valid options for NSCLC.

The Prognostic Value of RASGEF1A RNA Expression and DNA Methylation in Cytogenetically Normal Acute Myeloid Leukemia

Background Acute myeloid leukemia (AML) is a significantly heterogeneous malignancy of the blood. Cytogenetic abnormalities are crucial for the prognosis of AML. However, since more than half of patients with AML are cytogenetically normal AML (CN-AML), new markers are badly required for predicting prognosis. In recent years, gene abnormalities are considered to be strong prognostic factors of CN-AML, already having clinical significance for treatment. In addition, the relationship of methylation in some genes and AML prognosis predicting has been discovered. RASGEF1A is a guanine nucleotide exchange factors of Ras, and has been reported to relate to malignancy. However, there is no research about the relationship of RASGEF1A gene and CN-AML. Methods By integrating the Cancer Genome Atlas (TCGA) database 75 patients with CN-AML and 240 Gene Expression Omnibus (GEO) database CN-AML samples, we examined the association between RASGEF1A ’s RNA expression level and DNA methylation of and AML patients’ prognosis. Then, we investigated the RASGEF1A RNA expression and DNA methylation’s prognostic value in 77 patients with AML after allogeneic hematopoietic stem cell transplantation (Allo-HSCT) as well as 101 AML patients after chemotherapy respectively. We investigated the association between sensitivity to Crenolanib and expression level of RASGED1A in patients by integrating 191 CN-AML patients from BeatAML dadataset. Finally, we integrated the expression and methylation of RASGEF1A to predict the CN-AML patients’ prognosis. Results We found that RASGEF1A gene high expression group predicted poorer event-free survival (EFS) (P < 0.0001) as well as overall survival (OS) (P < 0.0001) in CN-AML samples, and the identical results were found in AML patients receiving chemotherapy (P < 0.0001) and Allo-HSCT (P < 0.0001). RASGEF1A RNA expression level is an CN-AML patients’ independent prognostic factor (EFS: HR = 5.5534, 95% CI: 1.2982–23.756, P = 0.0208; OS: HR = 5.3615, 95% CI: 1.1014–26.099, P = 0.0376). The IC50 (half maximal inhibitory concentration) of Crenolanib of CN-AML samples with RASGEF1A high expression level is lower. In addition, patients with high RASGEF1A methylation level had significant favorable prognosis (EPS: P < 0.0001, OS: P < 0.0001). Furthermore, the integrative analysis of expression and methylation of RASGEF1A could classify CN-AML patients into subgroups with different prognosis (EFS: P < 0.0001, OS: P < 0.0001). Conclusion Higher RASGEF1A RNA expression and lower DNA methylation predicts CN-AML patients’ poorer prognosis. The RASGEF1A high expression level from patients with CN-AML have better sensitivity to Crenolanib. The integrative analysis of RASGEF1A RNA expression and DNA methylation can provide a more accurate classification for prognosis. Lower RASGEF1A expression is a favorable prognostic factor for AML patients receiving chemotherapy or Allo-HSCT.

Characterization of glucosyltransferase and glucuronosyltransferase family members reveals how major flavone glycoside accumulate in the root of Scutellaria baicalensis

Flavonoid glycosides extracted from roots of Scutellaria baicalensis exhibit strong pharmaceutical effect in antitumor, antioxidative, anti-inflammatory, and antiviral activity. UDP glycosyltransferase family members are responsible for the transfer of a glycosyl moiety from UDP sugars to a wide range of acceptor flavonoids. Here, we report the phylogenetic analysis, tissue-specific expression and biochemical characterization of 10 glucosyltrasferases (SbUGTs) and 6 glucuronosyltransferases (SbUGATs) based on the recently released genome of S. baicalensis. These results reveal that the high expression level and affinity to substrate of SbUGAT4 make baicalin become the richest flavonoid glycoside in the root of S. baicalensis.

Developmental Robustness: The Haltere Case in Drosophila

Developmental processes have to be robust but also flexible enough to respond to genetic and environmental variations. Different mechanisms have been described to explain the apparent antagonistic nature of developmental robustness and plasticity. Here, we present a “self-sufficient” molecular model to explain the development of a particular flight organ that is under the control of the Hox gene Ultrabithorax (Ubx) in the fruit fly Drosophila melanogaster. Our model is based on a candidate RNAi screen and additional genetic analyses that all converge to an autonomous and cofactor-independent mode of action for Ubx. We postulate that this self-sufficient molecular mechanism is possible due to an unusually high expression level of the Hox protein. We propose that high dosage could constitute a so far poorly investigated molecular strategy for allowing Hox proteins to both innovate and stabilize new forms during evolution.