Identification and functional characteristics of CHD1L gene variants implicated in human Müllerian duct anomalies.

BACKGROUND: Müllerian duct anomalies (MDAs) are congenital developmental disorders that present as a series of abnormalities within the reproductive tracts of females. Genetic factors are linked to MDAs and recent advancements in whole-exome sequencing (WES) provide innovative perspectives in this field. However, relevant mechanism has only been investigated in a restricted manner without clear elucidation of respective observations. METHODS: Our previous study reported that 2 of 12 patients with MDAs harbored the CHD1L variant c.348-1G>C. Subsequently, an additional 85 MDAs patients were recruited. Variants in CHD1L were screened through the in-house database of WES performed in the cohort and two cases were identified. One presented with partial septate uterus with left renal agenesis and the other with complete septate uterus, duplicated cervices and longitudinal vaginal septum. The pathogenicity of the discovered variants was further assessed by molecular dynamics simulation and various functional assays. RESULTS: Ultimately, two novel heterozygous CHD1L variants, including a missense variant c.956G>A (p.R319Q) and a nonsense variant c.1831C>T (p.R611*) were observed. The variants were absent in 100 controls. Altogether, the contribution yield of CHD1L to MDAs was calculated as 4.12% (4/97). All three variants were assessed as pathogenic through various functional analysis. The splice-site variant c.348-1G>C resulted in a 11 bp sequence skipping in exon 4 of CHD1L and led to nonsense mediated decay of its transcripts. Unlike WT CHD1L, the truncated R611* protein mislocalized to the cytoplasm, abolish the ability of CHD1L to promote cell migration and failed to interact with PARP1 owing to the loss of macro domain. The R319Q variant exhibited conformational disparities and showed abnormal protein recruitment behavior through laser microirradiation comparing with the WT CHD1L. All these variants impaired the CHD1L function in DNA damage repair, thus participating in MDAs. CONCLUSIONS: The current study not only expands the mutational spectrum of CHD1L in MDAs but determines three variants as pathogenic according to ACMG guidelines with reliable functional evidence. Additionally, the impairment in DNA damage repair is an underlying mechanism involved in MDAs.

CHD1L Regulates Cell Survival in Breast Cancer and Its Inhibition by OTI-611 Impedes the DNA Damage Response and Induces PARthanatos.

The Chromodomain helicase DNA-binding protein 1-like (CHD1L) is a nucleosome remodeling enzyme, which plays a key role in chromatin relaxation during the DNA damage response. Genome editing has shown that deletion of CHD1L sensitizes cells to PARPi, but the effect of its pharmacological inhibition has not been defined. Triple-negative breast cancer SUM149PT, HCC1937, and MDA-MB-231 cells were used to assess the mechanism of action of the CHD1Li OTI-611. Cytotoxicity as a single agent or in combination with standard-of-care treatments was assessed in tumor organoids. Immunofluorescence was used to assess the translocation of PAR and AIF to the cytoplasm or the nucleus and to study markers of DNA damage or apoptosis. Trapping of PARP1/2 or CHD1L onto chromatin was also assessed by in situ subcellular fractionation and immunofluorescence and validated by Western blot. We show that the inhibition of CHD1L's ATPase activity by OTI-611 is cytotoxic to triple-negative breast cancer tumor organoids and synergizes with PARPi and chemotherapy independently of the BRCA mutation status. The inhibition of the remodeling function blocks the phosphorylation of H2AX, traps CHD1L on chromatin, and leaves PAR chains on PARP1/2 open for hydrolysis. PAR hydrolysis traps PARP1/2 at DNA damage sites and mediates PAR translocation to the cytoplasm, release of AIF from the mitochondria, and induction of PARthanatos. The targeted inhibition of CHD1L's oncogenic function by OTI-611 signifies an innovative therapeutic strategy for breast cancer and other cancers. This approach capitalizes on CHD1L-mediated DNA repair and cell survival vulnerabilities, thereby creating synergy with standard-of-care therapies.

The validation of new CHD1L inhibitors as a therapeutic strategy for cancer.

Chromodomain helicase DNA-binding protein 1 like (CHD1L) is an oncogene that promotes tumor progression, metastasis, and multidrug resistance. CHD1L expression is indicative of poor outcomes and low survival in cancer patients with various cancer types. Herein, we report a set of CHD1L inhibitors (CHD1Li) discovered from high-throughput screening and evaluated using enzyme inhibition, 3D tumor organoid cytotoxicity and mechanistic assays. The structurally distinct compounds 8-11 emerged as hits with promising bioactivity by targeting CHD1L. CHD1Li were further examined for their stability in human and mouse liver microsomes, which showed compounds 9 and 11 to be the most metabolically stable. Additionally, molecular modeling studies of CHD1Li with the target protein shed light on key pharmacophore features driving CHD1L binding. Taken together, these results expand the chemical space of CHD1Li as a potential targeted therapy for colorectal cancer and other cancers.

The SIRT7-mediated deacetylation of CHD1L amplifies HIF-2α-dependent signal that drives renal cell carcinoma progression and sunitinib resistance.

BACKGROUND: Aberrant interplay between epigenetic reprogramming and hypoxia signaling contributes to renal cell carcinoma progression and drug resistance, which is an essential hallmark. How the chromatin remodelers enhance RCC malignancy remains to be poorly understood. We aimed to elucidate the roles of CHD1L in determining hypoxia signaling activation and sunitinib resistance. METHODS: The qRT-PCR, western blotting, and immunohistochemistry technologies were used to detect CHD1L expressions. Lentivirus transfection was used to generate stable CHD1L-KD cells. The roles of SIRT7/CHD1L were evaluated by CCK-8, wound healing, transwell assays, xenograft models, and tail-vein metastasis models. Co-immunoprecipitation, Chromatin Immunoprecipitation (ChIP), and luciferase reporter assays were conducted to explore epigenetic regulations. RESULTS: We screened and validated that CHD1L is up-regulated in RCC and correlates with poorer prognosis of patients. CHD1L overexpression notably enhances cell proliferation, migration, and self-renewal capacities in vitro and in vivo. Mechanistically, SIRT7 physically interacts with CHDL1 and mediates the deacetylation of CHD1L. Wild-type SIRT7, but not H187Y dead mutant, stabilizes CHD1L protein levels via attenuating its ubiquitination levels. SIRT7 is increased in RCC and correlates with hazardous RCC clinical characteristics. SIRT7 depends on CHD1L to exert its tumor-promoting functions. Accumulated CHD1L amplifies HIF-2α-driven transcriptional programs via interacting with HIF-2α. CHD1L recruits BRD4 and increases the RNA polymerase II S2P loading. CHD1L ablation notably abolishes HIF-2α binding and subsequent transcriptional activation. CHD1L overexpression mediates the sunitinib resistance via sustaining VEGFA and targeting CHD1L reverses this effect. Specific CHD1L inhibitor (CHD1Li) shows a synergistic effect with sunitinib and strengthens its pharmaceutical effect. CONCLUSIONS: These results uncover a CHD1L-mediated epigenetic mechanism of HIF-2α activation and downstream sunitinib resistance. The SIRT7-CHD1L-HIF-2α axis is highlighted to predict RCC prognosis and endows potential targets.

A pan-cancer analysis reveals CHD1L as a prognostic and immunological biomarker in several human cancers.

Introduction: Several recent studies pointed out that chromodomain-helicase-DNA-binding protein 1-like (CHD1L) is a putative oncogene in many human tumors. However, up to date, there is no pan-cancer analysis performed to study the different aspects of this gene expression and behavior in tumor tissues. Methods: Here, we applied several bioinformatics tools to make a comprehensive analysis for CHD1L. Firstly we assessed the expression of CHD1L in several types of human tumors and tried to correlate that with the stage and grade of the analyzed tumors. Following that, we performed a survival analysis to study the correlation between CHD1L upregulation in tumors and the clinical outcome. Additionally, we investigated the mutation forms, the correlation with several immune cell infiltration, and the potential molecular mechanisms of CHD1L in the tumor tissue. Result and discussion: The results demonstrated that CHD1L is a highly expressed gene across several types of tumors and that was correlated with a poor prognosis for most cancer patients. Moreover, it was found that CHD1L affects the tumor immune microenvironment by influencing the infiltration level of several immune cells. Collectively, the current study provides a comprehensive overview of the oncogenic roles of CHD1L where our results nominate CHD1L as a potential prognostic biomarker and target for antitumor therapy development.

Genome-wide scanning for CHD1L gene in papillary thyroid carcinoma complicated with type 2 diabetes mellitus

Purpose Papillary thyroid carcinoma (PTC) represents the most common subtype of thyroid cancer (TC). This study was set out to explore the potential effect of CHD1L on PTC and type 2 diabetes mellitus (T2DM). Methods We searched for T2DM susceptibility genes through the GWAS database and obtained T2DM-related differentially expressed gene from the GEO database. The expression and clinical data of TC and normal samples were collated from the TCGA database. Receiver operating characteristic (ROC) curve analysis was subsequently applied to assess the sensitivity and specificity of the CHD1L for the diagnosis of PTC. The MCP-counter package in R language was then utilized to generate immune cell score to evaluate the relationship between CHD1L expression and immune cells. Then, we performed functional enrichment analysis of co-expressed genes and DEGs to determine significantly enriched GO terms and KEGG to predict the potential functions of CHD1L in PTC samples and T2DM adipose tissue. Results From two genes (ABCB9, CHD1L) were identified to be DEGs (p < 1 * 10−5) that exerted effects on survival (HR > 1, p < 0.05) in PTC and served as T2DM susceptibility genes. The gene expression matrix-based scoring of immunocytes suggested that PTC samples with high and low CHD1L expression presented with significant differences in the tumor microenvironment (TME). The enrichment analysis of CHD1L co-expressed genes and DEGs suggested that CHD1L was involved in multiple pathways to regulate the development of PTC. Among them, Kaposi sarcoma-associated herpesvirus infection, salmonella infection and TNF signaling pathways were highlighted as the three most relevant pathways. GSEA analysis, employed to analyze the genome dataset of PTC samples and T2DM adipose tissue presenting with high and low expression groups of CHD1L, suggests that these differential genes are related to chemokine signaling pathway, leukocyte transendothelial migration and TCELL receptor signaling pathway (AU)

Multiple roles for PARP1 in ALC1-dependent nucleosome remodeling.

The SNF2 family ATPase Amplified in Liver Cancer 1 (ALC1) is the only chromatin remodeling enzyme with a poly(ADP-ribose) (PAR) binding macrodomain. ALC1 functions together with poly(ADP-ribose) polymerase PARP1 to remodel nucleosomes. Activation of ALC1 cryptic ATPase activity and the subsequent nucleosome remodeling requires binding of its macrodomain to PAR chains synthesized by PARP1 and NAD+ A key question is whether PARP1 has a role(s) in ALC1-dependent nucleosome remodeling beyond simply synthesizing the PAR chains needed to activate the ALC1 ATPase. Here, we identify PARP1 separation-of-function mutants that activate ALC1 ATPase but do not support nucleosome remodeling by ALC1. Investigation of these mutants has revealed multiple functions for PARP1 in ALC1-dependent nucleosome remodeling and provides insights into its multifaceted role in chromatin remodeling.

Structure and dynamics of the chromatin remodeler ALC1 bound to a PARylated nucleosome.

The chromatin remodeler ALC1 is recruited to and activated by DNA damage-induced poly(ADP-ribose) (PAR) chains deposited by PARP1/PARP2/HPF1 upon detection of DNA lesions. ALC1 has emerged as a candidate drug target for cancer therapy as its loss confers synthetic lethality in homologous recombination-deficient cells. However, structure-based drug design and molecular analysis of ALC1 have been hindered by the requirement for PARylation and the highly heterogeneous nature of this post-translational modification. Here, we reconstituted an ALC1 and PARylated nucleosome complex modified in vitro using PARP2 and HPF1. This complex was amenable to cryo-EM structure determination without cross-linking, which enabled visualization of several intermediate states of ALC1 from the recognition of the PARylated nucleosome to the tight binding and activation of the remodeler. Functional biochemical assays with PARylated nucleosomes highlight the importance of nucleosomal epitopes for productive remodeling and suggest that ALC1 preferentially slides nucleosomes away from DNA breaks.

Renal agenesis-related genes are associated with Herlyn-Werner-Wunderlich syndrome.

OBJECTIVE: To explore the genetic causes of Herlyn-Werner-Wunderlich syndrome (HWWS) using whole-exome sequencing. DESIGN: Retrospective genetic study. SETTING: Academic medical center. PATIENT(S): Twelve patients with HWWS. INTERVENTION(S): Whole-exome sequencing was performed for each patient. Sanger sequencing was used to confirm the potential causative genetic variants. In silico analysis and American College of Medical Genetics and Genomics guidelines were used to classify the pathogenicity of each variant. MAIN OUTCOME MEASURE(S): Rare sequence variants associated with müllerian duct development and renal agenesis were identified and included in subsequent analyses. RESULT(S): A total of 11 variants were identified in 10 of 12 patients (83.3%) and were considered to constitute a molecular genetic diagnosis of HWWS. These 11 variants were related to 9 genes: CHD1L, TRIM32, TGFBR3, WNT4, RET, FRAS1, FAT1, FOXF1, and PCSK5. All variants were heterozygous and confirmed by Sanger sequencing. The changes included one frameshift variant, one splice-site variant, and eight missense variants. All of the identified variants were absent or rare in Genome Aggregation Database East Asian populations. One of the 11 variants (9.1%) was classified as a pathogenic variant according to the American College of Medical Genetics and Genomics guidelines, and 8 of the 11 variants (72.7%) were classified as variants of uncertain significance. CONCLUSION(S): To our knowledge, this is the first report of the genetic causes of HWWS. Renal agenesis-related genes, such as CHD1L, TRIM32, RET, and WNT4, may be associated with HWWS. Identification of these variants can not only help us understand the etiology of HWWS and the relationship between reproductive tract development and urinary system development, but additionally improve the level of genetic counseling for HWWS.

Genome-wide scanning for CHD1L gene in papillary thyroid carcinoma complicated with type 2 diabetes mellitus.

PURPOSE: Papillary thyroid carcinoma (PTC) represents the most common subtype of thyroid cancer (TC). This study was set out to explore the potential effect of CHD1L on PTC and type 2 diabetes mellitus (T2DM). METHODS: We searched for T2DM susceptibility genes through the GWAS database and obtained T2DM-related differentially expressed gene from the GEO database. The expression and clinical data of TC and normal samples were collated from the TCGA database. Receiver operating characteristic (ROC) curve analysis was subsequently applied to assess the sensitivity and specificity of the CHD1L for the diagnosis of PTC. The MCP-counter package in R language was then utilized to generate immune cell score to evaluate the relationship between CHD1L expression and immune cells. Then, we performed functional enrichment analysis of co-expressed genes and DEGs to determine significantly enriched GO terms and KEGG to predict the potential functions of CHD1L in PTC samples and T2DM adipose tissue. RESULTS: From two genes (ABCB9, CHD1L) were identified to be DEGs (p < 1 * 10-5) that exerted effects on survival (HR > 1, p < 0.05) in PTC and served as T2DM susceptibility genes. The gene expression matrix-based scoring of immunocytes suggested that PTC samples with high and low CHD1L expression presented with significant differences in the tumor microenvironment (TME). The enrichment analysis of CHD1L co-expressed genes and DEGs suggested that CHD1L was involved in multiple pathways to regulate the development of PTC. Among them, Kaposi sarcoma-associated herpesvirus infection, salmonella infection and TNF signaling pathways were highlighted as the three most relevant pathways. GSEA analysis, employed to analyze the genome dataset of PTC samples and T2DM adipose tissue presenting with high and low expression groups of CHD1L, suggests that these differential genes are related to chemokine signaling pathway, leukocyte transendothelial migration and TCELL receptor signaling pathway. CONCLUSION: CHD1L may potentially serve as an early diagnostic biomarker for PTC, and a target of immunotherapy for PTC and T2DM.

Suppressing CHD1L reduces the proliferation and chemoresistance in osteosarcoma.

Osteosarcoma (OS) is the most common bone malignant tumor. However, the genetic basis of OS pathogenesis is still not understood, and occurrence of chemo-resistance is a major reason for the high morbidity of OS patients. Recently, chromodomain helicase/ATPase DNA binding protein 1-like gene (CHD1L) has been identified as a gene related to malignant tumor progression. Unfortunately, its effects on OS development and drug resistance are still not understood. In the study, we attempted to investigate the effects of CHD1L on tumorigenesis and chemoresistance in OS. We found that CHD1L expression was markedly up-regulated in OS samples, especially in cisplatin (cDDP)-resistant patients. We also showed that OS cells with CHD1L knockdown were more sensitive to cDDP treatment with lower IC50 values. In addition, we found that CHD1L deletion markedly reduced cell proliferation and induced apoptosis in OS cells with cDDP resistance. Moreover, the properties of cancer stem cells were highly suppressed in cDDP-resistant OS cells following CHD1L knockdown. Furthermore, multidrug resistance protein 1 (MDR-1) expression levels were dramatically decreased in OS cells with cDDP resistance when CHD1L was suppressed. Functional analysis indicated that CHD1L knockdown clearly restrained the activation of ERK1/2, protein kinase B (AKT) and NF-κB signaling pathways in cDDP-resistant OS cells. Consistently, animal experiments suggested that CHD1L suppression mitigated cDDP resistance in the generated in vivo xenografts. Collectively, CHD1L could modulate chemoresistance of OS cells to cDDP, and thus may be inspiring findings for overcoming drug resistance in OS.

Diversity roles of CHD1L in normal cell function and tumorigenesis.

Chromodomain helicase/ATPase DNA binding protein 1-like gene (CHD1L) is a multifunctional protein participated in diverse cellular processes, including chromosome remodeling, cell differentiation and development. CHD1L is a regulator of chromosomal integrity maintenance, DNA repair and transcriptional regulation through its bindings to DNA. By regulating kinds of complex networks, CHD1L has been identified as a potent anti-apoptotic and pro-proliferative factor. CHD1L is also an oncoprotein since its overexpression leads to dysregulation of related downstream targets in various cancers. The latest advances in the functional molecular basis of CHD1L in normal cells will be described in this review. As the same time, we will describe the current understanding of CHD1L in terms of structure, characteristics, function and the molecular mechanisms underlying CHD1L in tumorigenesis. We inference that the role of CHD1L which involve in multiple cellular processes and oncogenesis is well worth further studying in basic biology and clinical relevance.

Mechanistic Insights into Regulation of the ALC1 Remodeler by the Nucleosome Acidic Patch.

Upon DNA damage, the ALC1/CHD1L nucleosome remodeling enzyme (remodeler) is activated by binding to poly(ADP-ribose). How activated ALC1 recognizes the nucleosome, as well as how this recognition is coupled to remodeling, is unknown. Here, we show that remodeling by ALC1 requires a wild-type acidic patch on the entry side of the nucleosome. The cryo-electron microscopy structure of a nucleosome-ALC1 linker complex reveals a regulatory linker segment that binds to the acidic patch. Mutations within this interface alter the dynamics of ALC1 recruitment to DNA damage and impede the ATPase and remodeling activities of ALC1. Full activation requires acidic patch-linker segment interactions that tether the remodeler to the nucleosome and couple ATP hydrolysis to nucleosome mobilization. Upon DNA damage, such a requirement may be used to modulate ALC1 activity via changes in the nucleosome acidic patches.

CHD1L promotes EOC cell invasiveness and metastasis via the regulation of METAP2.

Chromodomain helicase DNA binding protein 1-like (CHD1L) gene has been proposed to play an oncogenic role in human hepatocellular carcinoma. Previously we reported that CHD1L overexpression is significantly associated with the metastasis proceeding of epithelial ovarian cancer (EOC), and may predict a poor prognosis in EOC patients. However, the potential oncogenic mechanisms by which CHD1L acts in EOC remain unclear. To elucidate the oncogenic function of CHD1L, we carried out a series of in vitro assays, with effects of CHD1L ectogenic overexpression and silencing being determined in EOC cell lines (HO8910, A2780 and ES2). Real-time PCR and Western blotting analyses were used to identify potential downstream targets of CHD1L in the process of EOC invasion and metastasis. In ovarian carcinoma HO8910 cell lines, ectopic overexpression of CHD1L substantially induced the invasive and metastasis ability of the cancer cells in vitro. In contrast, knockdown of CHD1L using shRNA inhibited cell invasion in vitro in ovarian carcinoma A2780 and ES2 cell lines. We also demonstrated that methionyl aminopeptidase 2 (METAP2) was a downstream target of CHD1L in EOC, and we found a significant, positive correlation between the expression of CHD1L and METAP2 in EOC tissues (P<0.05). Our findings indicate that CHD1L plays a potential role in the inducement of EOC cancer cell invasion and/or metastasis via the regulation of METAP2 expression and suggests that CHD1L inhibition may provide a potential target for therapeutic intervention in human EOC.

Molecular Characterization of the Oncogene BTF3 and Its Targets in Colorectal Cancer.

Colorectal cancer (CRC) is one of the most commonly diagnosed and leading causes of cancer mortality worldwide, and the prognosis of patients with CRC remains unsatisfactory. Basic transcription factor 3 (BTF3) is an oncogene and hazardous prognosticator in CRC. Although two distinct functional mechanisms of BTF3 in different cancer types have been reported, its role in CRC is still unclear. In this study, we aimed to molecularly characterize the oncogene BTF3 and its targets in CRC. Here, we first identified the transcriptional targets of BTF3 by applying combined RNA-Seq and ChIP-Seq analysis, identifying CHD1L as a transcriptional target of BTF3. Thereafter, we conducted immunoprecipitation (IP)-MS and E3 ubiquitin ligase analysis to identify potential interacting targets of BTF3 as a subunit of the nascent-polypeptide-associated complex (NAC). The analysis revealed that BTF3 might also inhibit E3 ubiquitin ligase HERC2-mediated p53 degradation. Finally, miRNAs targeting BTF3 were predicted and validated. Decreased miR-497-5p expression is responsible for higher levels of BTF3 post-transcriptionally. Collectively, we concluded that BTF3 is an oncogene, and there may exist a transcription factor and NAC-related proteolysis mechanism in CRC. This study provides a comprehensive basis for understanding the oncogenic mechanisms of BTF3 in CRC.

Chromodomain-helicase-DNA-binding protein 1-like (CHD1L) silencing inhibits gastric cancer cell proliferation, invasion, and migration.

BACKGROUND: We aimed to investigate the effect of chromodomain-helicase-DNA-binding protein 1-like (CHD1L) silencing on the biological behavior of gastric cancer cells. METHODS: Small hairpin RNA (shRNAs) targeting CHD1L were designed and transduced into BGC-823 human gastric cancer cells. Expression of p53, p21, nerve growth factor IB (Nur77), and ARHGEF9 was assessed by western blotting, and the effect of CHD1L silencing on gastric cancer cell proliferation, apoptosis, and migration was examined by MTT, flow cytometry, and wound healing assays, respectively. RESULTS: In CHD1L-shRNA-1-treated cells, the expression of p53, p21, Nur77, and ARHGEF9 was significantly upregulated, and the number of apoptotic cells was significantly increased compared to the shRNA-negative control (NC; P<0.05). Additionally, the number of cells in the G1 phase was significantly increased among CHD1L-shRNA-1-treated cells. In contrast, the number of cells in the S phase was significantly decreased among CHD1L-shRNA-1-treated cells compared to shRNA-NC-treated cells (P<0.05). Following CHD1L silencing, there were 58.63±10.97 invading cells compared to 144.95±12.68 and 148.49±17.86 in the shRNA-NC and untreated groups, respectively (P<0.05). After 24 h, CHD1L-silenced BGC-823 cells migrated 0.54±0.34 µm compared to 1.34±0.26 and 1.31±0.31 µm in the shRNA-NC and untreated groups, respectively (P<0.05). CONCLUSIONS: CHD1L silencing significantly inhibited the proliferation, invasion, and migration of BGC-823 gastric cancer cells and induced apoptosis. Knockdown of CHD1L may present a novel approach for treating gastric cancer.

Detection of a familial 1q21.1 microdeletion and concomitant CHD1L mutation in a fetus with oligohydramnios and bilateral renal dysplasia on prenatal ultrasound.

OBJECTIVE: We present detection of a familial 1q21.1 microdeletion and concomitant CHD1L mutation in a fetus with oligohydramnios and bilateral renal dysplasia on prenatal ultrasound. CASE REPORT: A 37-year-old, primigravid woman was referred for level II ultrasound examination at 16 weeks of gestation because of oligohydramnios. The parents were phenotypically normal, and there were no congenital malformations in the family. Prenatal ultrasound at 17 weeks of gestation revealed a fetus with fetal growth biometry equivalent to 16 weeks, oligohydramnios with an amniotic fluid index (AFI) of 1.4 cm and bilateral renal dysplasia without sonographic demonstration of bilateral renal arteries. The pregnancy was subsequently terminated, and a 137-g fetus was delivered without characteristic facial dysmorphism. Postnatal cytogenetic analysis of the umbilical cord and parental bloods revealed normal karyotypes. However, array comparative genomic hybridization (aCGH) analysis on the DNA extracted from the umbilical cord revealed a 2.038-Mb microdeletion of 1q21.1-q21.2 encompassing 11 [Online Mendelian Inheritance in Man (OMIM)] genes of PRKAB2, FMO5, CHD1L, BCL9, ACP6, GJA5, GJA8, GPR89B, NBPF14, TRN-GTT2-1 and NBPF20. The mother was found to carry the same microdeletion. A missense mutation of c.2353T > G, p.Ser785Ala in CHD1L was detected in the umbilical cord. The father was found to carry a heterozygous mutation of c.2353T > G, p.Ser785Ala in CHD1L. CONCLUSION: Fetuses with a 1q21.1 microdeletion and concomitant CHD1L mutation may present oligohydramnios and bilateral renal dysplasia on prenatal ultrasound.

CHD1L promotes cell cycle progression and cell motility by up-regulating MDM2 in breast cancer.

Chromodomain helicase/ATPase DNA-binding protein 1-like (CHD1L) gene is a novel oncogene amplified in many solid tumors. We investigated its role in breast cancer. CHD1L was over-expressed in 49.1% (57/116) breast cancer patients. Overexpression of CHD1L was significantly associated with younger age at diagnosis (P = 0.016), lymph node involvement (P = 0.040), higher tumor grade (P = 0.027), higher proliferation rate (P = 0.007) and shorter disease-free survival rate (77.2% vs. 91.5%, P = 0.037). A cDNA microarray analysis identified MDM2 as an important downstream target of CHD1L. And MDM2/p53 signaling pathway was showed to be significantly modulated by CHD1L. Further in vitro study showed that overexpression of CHD1L can promote tumorigenesis, metastasis, invasion and cell cycle progress. In vivo study confirmed the tumorigenesis ability of CHD1L. shRNA-mediated CHD1L silencing could abolishes the tumor-promotion effect of CHD1L in vitro and in vivo. In conclusion, CHD1L may promote the progress of breast cancer cells via the MDM2/p53 signaling pathway. This study identified CHD1L as a prognostic factor for breast cancer and MDM2 might be used as a potential target for therapeutic intervention in CHD1L overexpression breast cancer.

A Novel Regulatory Axis, CHD1L-MicroRNA 486-Matrix Metalloproteinase 2, Controls Spermatogonial Stem Cell Properties.

Spermatogonial stem cells (SSCs) are unipotent germ cells that are at the foundation of spermatogenesis and male fertility. However, the underlying molecular mechanisms governing SSC stemness and growth properties remain elusive. We have recently identified chromodomain helicase/ATPase DNA binding protein 1-like (Chd1l) as a novel regulator for SSC survival and self-renewal, but how these functions are controlled by Chd1l remains to be resolved. Here, we applied high-throughput small RNA sequencing to uncover the microRNA (miRNA) expression profiles controlled by Chd1l and showed that the expression levels of 124 miRNA transcripts were differentially regulated by Chd1l in SSCs. KEGG pathway analysis shows that the miRNAs that are differentially expressed upon Chd1l repression are significantly enriched in the pathways associated with stem cell pluripotency and proliferation. As a proof of concept, we demonstrate that one of the most highly upregulated miRNAs, miR-486, controls SSC stemness gene expression and growth properties. The matrix metalloproteinase 2 (MMP2) gene has been identified as a novel miR-486 target gene in the context of SSC stemness gene regulation and growth properties. Data from cotransfection experiments showed that Chd1l, miR-486, and MMP2 work in concert in regulating SSC stemness gene expression and growth properties. Finally, our data also revealed that MMP2 regulates SSC stemness gene expression and growth properties through activating ß-catenin signaling by cleaving N-cadherin and increasing ß-catenin nuclear translocation. Our data demonstrate that Chd1l-miR-486-MMP2 is a novel regulatory axis governing SSC stemness gene expression and growth properties, offering a novel therapeutic opportunity for treating male infertility.

Clinical significance of chromodomain helicase/ATPase DNA binding protein 1-like and human mutL homolog 1 gene expression in cholangiocarcinoma.

Cholangiocarcinoma is a highly malignant form of gastrointestinal cancer with an unfavorable prognosis. The novel oncogene chromodomain helicase/ATPase DNA binding protein 1-like (CHD1L) has been confirmed to serve a vital role in numerous types of cancer, including liver cancer. Mismatch repair (MMR) is a common DNA repair process that contributes to the preservation of the integrity and stability of genetic substances. Human mutL homolog 1 gene (hMLH1) is an important MMR protein family member. The present study aimed to evaluate the pathological and clinical features of cholangiocarcinoma, and to investigate the clinical significance of CHD1L and hMLH1 expression in cholangiocarcinoma. A total of 108 samples from cholangiocarcinoma tumor tissues and 60 samples from normal bile duct tissue were obtained from patients admitted to The Second Affiliated Hospital of Nanchang University between May 2005 and May 2014. All cholangiocarcinoma cases were pathologically confirmed. The expression of CHD1L and hMLH1 was examined by immunohistochemistry analysis. The expression of CHD1L in cholangiocarcinoma (94.44%) was significantly higher than in normal bile duct tissues (40.00%). CHD1L expression was associated with gallstone history, serum carbohydrate antigen 19-9 (CA19-9) level and Tumor-Node-Metastasis (TNM) stage (P<0.05). hMLH1 expression in cholangiocarcinoma (77.78%) was significantly lower than in normal bile duct tissues (96.67%), and was associated with gender, age, serum CA19-9 level, the presence of hepatitis B virus surface antigen, TNM stage and tumor diameter (P<0.05). Kaplan-Meier survival curve analysis indicated that the 3-year accumulative survival rates for CHD1L-positive and -negative patients differed significantly (P<0.05; 17.90 and 83.33%, respectively). There was no statistically significant difference (P>0.05) between the 3-year accumulate survival rates for hMLH1-positive and -negative patients (38.90 and 33.30%, respectively). High CHD1L expression and low hMLH1 expression levels were observed in patients with cholangiocarcinoma, and their abnormal expression patterns were associated with the progression of malignancy and an unfavorable disease prognosis. Therefore, CHD1L and hMLH1 may be potential prognostic biomarkers for cholangiocarcinoma.