The off-target effects of AID in carcinogenesis.

Activation-induced cytidine deaminase (AID) plays a crucial role in promoting B cell diversification through somatic hypermutation (SHM) and class switch recombination (CSR). While AID is primarily associated with the physiological function of humoral immune response, it has also been linked to the initiation and progression of lymphomas. Abnormalities in AID have been shown to disrupt gene networks and signaling pathways in both B-cell and T-cell lineage lymphoblastic leukemia, although the full extent of its role in carcinogenesis remains unclear. This review proposes an alternative role for AID and explores its off-target effects in regulating tumorigenesis. In this review, we first provide an overview of the physiological function of AID and its regulation. AID plays a crucial role in promoting B cell diversification through SHM and CSR. We then discuss the off-target effects of AID, which includes inducing mutations of non-Igs, epigenetic modification, and the alternative role as a cofactor. We also explore the networks that keep AID in line. Furthermore, we summarize the off-target effects of AID in autoimmune diseases and hematological neoplasms. Finally, we assess the off-target effects of AID in solid tumors. The primary focus of this review is to understand how and when AID targets specific gene loci and how this affects carcinogenesis. Overall, this review aims to provide a comprehensive understanding of the physiological and off-target effects of AID, which will contribute to the development of novel therapeutic strategies for autoimmune diseases, hematological neoplasms, and solid tumors.

Universal nanosonosensitizer for ROS-mediated reduction of various cancer cells.

Sonodynamic therapy (SDT) has attracted great attention due to its deep tissue penetration, uniform tissue energy distribution, and noninvasiveness features. Additionally, external triggers can precisely focus on the tumor site with good specificity and high controllability. In the past decade, numerous sonosensitizers have been designed and used for SDT. However, the research and development of universal sonosensitizers for many different types of tumors are equally important in clinical treatment. Herein, we synthesized and studied the universality of four MWO4-PEG nanoparticles (NPs). All of the four MWO4-PEG NPs exhibited highly efficient ultrasound (US)-triggered production of 1O2 and ˙OH, enabling effective decreased cell viability, increased cell apoptosis rate, and a destruction of mouse tumors under US stimulation. The US-triggered NPs indicated good sonosensitivity and low toxicity to nine kinds of cancer cells. After accomplishing its therapeutic functions, NiWO4-PEG could be metabolized by the mouse body without any long-term toxicity. The PEGylated MWO4-PEG NPs shown in this study would provide efficient and universal US-triggered cancer therapy with the advantages of a cost-effective, convenient, and noninvasive agent that is promising for noninvasive SDT cancer treatment.

Synthesis and Biological Evaluation of PEGylated MWO4 Nanoparticles as Sonodynamic AID Inhibitors in Treating Diffuse Large B-Cell Lymphoma.

Sonodynamic therapy (SDT) triggered by ultrasound (US) has attracted increasing attention owing to its ability to overcome critical limitations, including low tissue-penetration depth and phototoxicity in photodynamic therapy (PDT). Biogenic metal oxide nanoparticles (NPs) have been used as anti-cancer drugs due to their biocompatibility properties with most biological systems. Here, sonosensitizer MWO4-PEG NPs (M = Fe Mn Co Ni) were synthesized as inhibitors to activation-induced cytidine deaminase (AID), thus neutralizing the extensive carcinogenesis of AID in diffuse large B-cell lymphoma (DLBCL). The physiological properties of these nanomaterials were examined using transmission electron microscopy (TEM). The inhibition of NPs to AID was primarily identified by the affinity interaction prediction between reactive oxygen species (ROS) and AID through molecular dynamics and molecular docking technology. The cell apoptosis and ROS generation in US-triggered NPs treated DLBCL cells (with high levels of AID) were also detected to indicate the sonosensitivity and toxicity of MWO4-PEG NPs to DLBCL cells. The anti-lymphoma studies using DLBCL and AID-deficient DLBCL cell lines indicated a concentration-dependent profile. The synthesized MWO4-PEG NPs in this study manifested good sonodynamic inhibitory effects to AID and well treatment for AID-positive hematopoietic cancers.

Involvement of Blnk and Foxo1 in tumor suppression in BCR­ABL1­transformed pro­B cells.

Oncogenic Bcr­Abl kinase mimics pre­B cell receptor (pre­BCR) survival signals in BCR­ABL1­positive B­cell acute lymphoblastic leukemia (BCR­ABL1+ B­ALL), driving B­cell progenitor malignant transformation; thus, defining a particularly unfavorable prognosis for patients. During B­cell development, pre­BCR differentiation signaling components terminate proliferative expansion and promote B­cell maturation. To study whether pre­BCR differentiation signaling components regulate the initiation and development of BCR­ABL1+ B­ALL, the tumor suppression mechanism of differentiation­related signaling molecules in BCR­ABL1­transformed pro­B cells were analyzed. The results demonstrated that Bcr­Abl kinase activated the PI3K/Akt pathway, promoting cell growth, and upregulated Aid expression, increasing genomic instability in pro­B cells. These findings suggest that Bcr­Abl kinase mediates pro­B cell malignant transformation. Furthermore, the present data revealed that BCR­ABL1 oncogenic stress triggered enhanced expression of B­cell differentiation components B­cell linker (Blnk) and forkhead box protein O1 (Foxo1) in BCR­ABL1 transformed pro­B cells. Using the CRISPR/Cas9­mediated Blnk or Foxo1 knockout BCR­ABL1­transformed pro­B cells, it was identified that, in BCR­ABL1­transformed pro­B cells, Blnk and Foxo1 reduced Bcr­Abl kinase activity to induce cell cycle arrest and decrease genomic instability. In addition, Blnk suppressed the PI3K/Akt pathway to reduce Foxo1 phosphorylation and heighten the Foxo1 activity, indicating that, in BCR­ABL1­transformed pro­B cells, Foxo1 participated in the regulation of Bcr­Abl kinase by Blnk. The present data highlighted the antitumor mechanisms of Blnk and Foxo1 in the regulation of Bcr­Abl kinase, and thus, may offer an alternative therapeutic strategy to Bcr­Abl kinase regulation in BCR­ABL1+ B­ALL.

CD19-targeting fusion protein combined with PD1 antibody enhances anti-tumor immunity in mouse models.

In our previous studies, using a B cell vaccine (scFv-Her2), the targeting of tumor-associated antigen Her2 (human epidermal growth factor receptor-2) to B cells via the anti-CD19 single chain variable fragment (scFv) was shown to augment tumor-specific immunity, which enhanced tumor control in the prophylactic and therapeutic setting. However, the fusion protein displayed limited activity against established tumors, and local relapses often occurred following scFv-Her2 treatment, indicating that scFv-Her2-induced responses are inadequate to maintain anti-tumor immunity. In this study, targeting the IV region (D4) of the extracellular region of Her2 to B cells via CD19 molecules (scFv-Her2D4) was found to enhance IFN-γ-producing-CD8+ T cell infiltration in tumor tissues and reduced the number of tumor-infiltrating myeloid-derived suppressor cells (MDSCs). However, negative co-stimulatory molecules such as programmed cell death protein-1 (PD-1), CD160, and LAG-3 on T cells and programmed death protein ligand-1 (PD-L1) on tumor cells were upregulated in the tumor microenvironment after scFv-Her2D4 treatment. Further, anti-PD1 administration enhanced the efficacy of scFv-Her2D4 and anti-tumor immunity, as evidenced by the reversal of tumor-infiltrating CD8+ T cell exhaustion and the reduction of MDSCs and Treg cells, which suppress T cells and alter the tumor immune microenvironment. Moreover, combining this with anti-PD1 antibodies promoted complete tumor rejection. Our data provide evidence of a close interaction among tumor vaccines, T cells, and the PD-L1/PD-1 axis and establish a basis for the rational design of combination therapy with immune modulators and tumor vaccine therapy.

AID assists DNMT1 to attenuate BCL6 expression through DNA methylation in diffuse large B-cell lymphoma cell lines.

The BCL6 proto-oncogene encodes a transcriptional repressor, which is required for germinal centers (GCs) formation and lymphomagenesis. Previous studies have been reported that the constitutive expression of BCL6 leads to diffuse large B cell lymphoma (DLBCL) through activation-induced cytidine deaminase (AID) mediated chromosomal translocations and mutations. However, other DLBCLs (45%) without structural variants were characterized by abnormally high level of BCL6 expression through an unknown mechanism. Herein, we report that deficiency in AID or methyltransferase 1 (DNMT1) triggers high level of BCL6 expression. AID-DNMT1 complex binds to -0.4 kb -0 kb region of BCL6 promoter and contributes to generate BCL6 methylation which results in inhibition of BCL6 expression. The proteasome pathway inhibitor MG132 induces accumulation of AID and DNMT1, causes decreased BCL6 expression, and leads to cell apoptosis and tumor growth inhibition in DLBCL cell xenograft mice. These findings propose mechanistic insight into an alternative cofactor role of AID in assisting DNMT1 to maintain BCL6 methylation, thus suppress BCL6 transcription in DLBCL. This novel mechanism will provide a new drug selection in the therapeutic approach to DLBCL in the future.

Down-regulation effects of IFN-α on p11, 5-htr1b and 5-HTR4 protein levels were affected by NH4CL or MG132 treatment in SH-sy5y cells.

In previous studies, we found interferon-α (IFN-α) could reduce protein levels of p11, 5-hydroxytryptamine receptor 1b (5-HT1b) and 5-hydroxytryptamine receptor 4 (5-HT4), but does not influence their messenger RNA levels in SH-sy5y cells. Thus, we investigated the post-transcriptional modulation of these molecules by IFN-α. SH-sy5y cells were treated with IFN-α, NH4Cl or MG132 alone or in combination, and then the protein levels of p11, 5-HT1b and 5-HT4 were analyzed by western blots. The regulatory effects of p11 on 5-HT1b and 5-HT4 were also determined in p11 knock-down cells. NH4Cl but not MG132 could reverse the protein level of p11 in IFN-α-treated SH-sy5y cells. MG132 could recover the protein levels of 5-HT1b and 5-HT4 in p11 knock-down cells. The down-regulation effects of IFN-α on p11, 5-HT1b and 5-HT4 were associated with the lysosome and ubiquitin-proteasome-mediated pathways. p11 was identified as a potent regulator to modulate the ubiquitination of 5-HT1b and 5-HT4. Therefore, it could be potential target therapies in IFN-ainduced depression.

Identification and characterization of a murine model of BCR­ABL1+ acute B­lymphoblastic leukemia with central nervous system metastasis.

Breakpoint cluster region (BCR)­Abelson murine leukemia (ABL)1+ acute B­lymphoblastic leukemia (B­ALL) is a disease associated with a dismal prognosis and a high incidence of central nervous system (CNS) metastasis. However, BCR­ABL1+ B­ALL with CNS infiltration has not been previously characterized, at least to the best of our knowledge. In the present study, a murine model of BCR­ABL1+ B­ALL with CNS metastasis was established using retroviral transduction. The vast majority of BCR­ABL1+ leukemic cells were found to be immature B cells with a variable proportion of pro­B and pre­B populations. The present results indicated that the BCR­ABL1+ B­leukemic cells expressed high levels integrin subunit alpha 6 (Itga6) and L­selectin adhesion molecules, and have an intrinsic ability to disseminate and accumulate in CNS tissues, predominantly in meninges. On the whole, these results provide an approach for addressing the mechanisms of BCR­ABL1+ B­ALL with CNS metastasis and may guide the development of novel therapeutic strategies.

Association of serum interleukin-10, interleukin-17A and transforming growth factor-α levels with human benign and malignant breast diseases.

Interleukin-10 (IL-10), interleukin-17A (IL-17A) and transforming growth factor α (TGF-α) have been implicated in the progression of breast cancer. However, the diagnostic and prognostic roles of these cytokines in ductal carcinoma remain unclear. The present study therefore aimed to determine the serum levels of IL-10, IL-17 and TGF-α in subjects with benign and malignant breast diseases and to evaluate the clinical significance of these cytokines in ductal carcinoma. Pre-operative serum samples were collected from 378 patients with breast disease and 70 healthy subjects. IL-10, IL-17A and TGF-α levels were measured using ELISA. Serum levels of these cytokine in patients with different breast diseases were evaluated. Furthermore, correlations between levels of these cytokines and the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) in ductal carcinoma were determined. The results demonstrated that serum levels of IL-10 and IL-17A were significantly increased in subjects with atypical hyperplasia and ductal carcinoma. Furthermore, IL-10 and IL-17A levels were increased in patients with a more serious clinical tumor stage and tumors that were ER- and PR-. Furthermore, high serum levels of TGF-α were associated with HER2+ tumors. A strong positive correlation was identified between TGF-α and IL-17A levels. Therefore, the results of the current study revealed that elevated serum IL-10, IL-17A and TGF-α levels are strongly associated with ductal carcinoma, specifically with tumor stage. High serum levels of IL-10 and IL-17A were also associated with the negative expression of ER and PR in ductal carcinoma, and high serum levels of TGF-α were associated with the positive expression of HER2 in ductal carcinoma. Thus, serum cytokine levels may be measured to identify patients with a poor prognosis who may benefit from more aggressive management and treatment.

HTLV-1 Tax upregulates early growth response protein 1 through nuclear factor-κB signaling.

Human T cell leukemia virus type 1 (HTLV-1) is a complex retrovirus that causes adult T cell leukemia (ATL) in susceptible individuals. The HTLV-1-encoded oncoprotein Tax induces persistent activation of the nuclear factor-κB (NF-κB) pathway. Early growth response protein 1 (EGR1) is overexpressed in HTLV-1-infected T cell lines and ATL cells. Here, we showed that both Tax expression and HTLV-1 infection promoted EGR1 overexpression. Loss of the NF-κB binding site in the EGR1 promotor or inhibition of NF-κB activation reduced Tax-induced EGR1 upregulation. Tax mutants unable to activate NF-κB induced only slight EGR1 upregulation as compared with wild-type Tax, confirming NF-κB pathway involvement in EGR1 regulation. Tax also directly interacted with the EGR1 protein and increased endogenous EGR1 stability. Elevated EGR1 in turn promoted p65 nuclear translocation and increased NF-κB activation. These results demonstrate a positive feedback loop between EGR1 expression and NF-κB activation in HTLV-1-infected and Tax-expressing cells. Both NF-κB activation and Tax-induced EGR1 stability upregulated EGR1, which in turn enhanced constitutive NF-κB activation and facilitated ATL progression in HTLV-1-infected cells. These findings suggest EGR1 may be an effective anti-ATL therapeutic target.

Epigenetic modifications of the VH region after DJH recombination in Pro-B cells.

The variable region of murine immunoglobulin heavy chain (Igh) is assembled by sequential DH -JH and VH -DJH recombination. The accessibility of the Igh locus determines the order of rearrangement. Because of the large number of VH genes and the lack of a suitable model, the epigenetic modifications of VH genes after DJH recombination have not previously been characterized. Here, we employed two v-Abl pro-B cell lines, in which the Igh locus is in germline and DJH -recombined configurations, respectively. The DJH junction displays the characteristics of a recombination centre, such as high levels of activation-associated histone modifications and recombination-activating gene protein (RAG) binding in DJH -rearranged pro-B cells, which extend the recombination centre model proposed for the germline Igh locus. The different domains of the VH region have distinct epigenetic characteristics after DJH recombination. Distal VH genes have higher levels of active histone modifications, germline transcription and Pax5 binding, and good quality recombination signal sequences. Proximal VH genes are relatively close to the DJH recombination centre, which partially compensates for the low levels of the above active epigenetic modifications. DJH recombination centre might serve as a cis-acting element to regulate the accessibility of the VH region. Furthermore, we demonstrate that RAG weakly binds to functional VH genes, which is the first detailed assessment of RAG dynamic binding to VH genes. We provide a way for VH -DJH recombination in which the VH gene is brought into close proximity with the DJH recombination centre for RAG binding by a Pax5-dependent chromosomal compaction event, and held in this position for subsequent cleavage and VH -DJH joining.

Targeting of interleukin (IL)-17A inhibits PDL1 expression in tumor cells and induces anticancer immunity in an estrogen receptor-negative murine model of breast cancer.

The expression of IL-17A and programmed death ligand 1 (PDL1) is increased in estrogen receptor-negative breast cancer. IL-17A promotes tumor cell survival and invasiveness and inhibits the antitumor immune response. The PDL1-PD1 (programmed death protein 1) signaling pathway promotes escape from immune surveillance in tumor cells. The pro-tumor properties of IL-17A and PDL1 in various cancers have been previously examined; however, the relationship and roles of IL-17A and PDL1 in ER-negative breast cancer have not been evaluated. Therefore, we assessed whether IL-17A promotes PDL1 expression in tumor cells and whether targeting of IL-17A could inhibit ER-negative breast cancer progression in a murine model. Our study revealed that IL-17A promoted PDL1 expression in human and mouse cells. In the murine cancer model, targeting of IL-17A inhibited PDL1 expression in the tumor microenvironment, decreased the percentage of Treg cells in tumor-infiltrating lymphocytes, and promoted CD4+ and CD8+ T cells to secrete interferon gamma. More importantly, treatment with combined anti-IL-17A and anti-PDL1 antibodies enhanced antitumor effects in favor of tumor eradication. Thus, our study established a pro-tumor role of IL-17A in promoting tumor immune escape and supports the development of a novel cytokine immunotherapy against breast cancer.

Female specific association between NNMT gene and schizophrenia in a Han Chinese population.

Accumulating evidence has shown that alterations in one carbon metabolism might play an important role in the pathogenesis of schizophrenia (SZ). Nicotinamide-N-methyltransferase (NNMT) is one of the key enzymes of one-carbon metabolism. To examine whether NNMT gene was associated with SZ in Han Chinese population, we selected seven single nucleotide polymorphisms (SNPs) in NNMT gene, and investigated its association with SZ from a cohort of 42 SZ patients and 86 healthy controls by Mass-ARRAY technology. Statistical analyses revealed that one (rs694539) of the SNPs in the female subgroup showed significant difference between SZ patients and controls both in genotypic (p= 0.0170) and allelic frequencies (p = 0.0059). We also found that the frequency of haplotype 'A G G C T C T' in the female patients was significantly higher than in controls (p=0.0015). Our results suggest that NNMT rs694539 may have a role in the etiology of SZ in a Han Chinese female population.

Analysis of methylated patterns and quality-related genes in tobacco (Nicotiana tabacum) cultivars.

Methylation-sensitive amplified polymorphism was used in this study to investigate epigenetic information of four tobacco cultivars: Yunyan 85, NC89, K326, and Yunyan 87. The DNA fragments with methylated information were cloned by reamplified PCR and sequenced. The results of Blast alignments showed that the genes with methylation information included chitinase, nitrate reductase, chloroplast DNA, mitochondrial DNA, ornithine decarboxylase, ribulose carboxylase, and promoter sequences. Homologous comparison in three cloned gene sequences (nitrate reductase, ornithine decarboxylase, and ribulose decarboxylase) indicated that geographic factors had significant influence on the whole genome methylation. Introns also contained different information in different tobacco cultivars. These findings suggest that synthetic mechanisms for tobacco aromatic components could be affected by different environmental factors leading to variation of noncoding regions in the genome, which finally results in different fragrance and taste in different tobacco cultivars.

Mitochondrial haplogroups and hypervariable region polymorphisms in schizophrenia: a case-control study.

Previous studies have detected associations between mitochondrial haplogroups and schizophrenia (SZ). However, no study has examined the relationship between major mitochondrial DNA (mtDNA) haplogroups and SZ in the Chinese population. The aim of this study was to assess the association between mtDNA haplogroups and SZ genesis in the Chinese Han population. We used a case-control study and sequenced the mtDNA hypervariable regions (HVR1, HVR2, and HVR3) in the Han population. We analyzed mtDNA haplogroups and HVR polymorphisms in 298 SZ patients and 298 controls. The haplotypes were classified into 10 major haplogroups: A, B, CZ, D, F, G, M, N, N9a, and R. Statistical analysis revealed that only N9a showed a nominally significant association with protection from SZ [1.68% vs. 6.38%, p=0.004, OR=0.251 (0.092-0.680); after adjustment for age and sex: p=0.006, OR=0.246 (0.090-0.669)]. Three HVR polymorphisms were found to be nominally significantly different between subjects with SZ and controls, and all except one (m.204T>C) are linked to the N9a haplogroup. Our results indicate that mtDNA haplogroup N9a might be a protective factor for SZ.