Discovery and characterization of potent And-1 inhibitors for cancer treatment

Design, synthesis, and evaluation of novel stilbene derivatives that degrade acidic nucleoplasmic DNA-binding protein 1 (And1) and synergize with PARP1 inhibitor in NSCLC cells

Specifically inducing the degradation of acidic nucleoplasmic DNA-binding protein 1 (And1) is a promising antitumor strategy. Our previous study identified Bazedoxifene (BZA) and CH3 as specific And1 degraders and validated their activity in reversing radiotherapy resistance in vitro and in vivo. However, unelucidated structure-activity relationships and moderate activity have limited their application. In this study, 27 novel CH3 derivatives were designed and synthesised based on the cavity topology of the WD40 domain of And1. Among them, A15 with a "V" conformation significantly induced And1 degradation in NSCLC cells. In addition, this study demonstrated a potential synthetic lethal effect of And1 degraders and PARP1 inhibitors. 1 µM of Olaparib in combination with 5 µM of A15 significantly inhibited the proliferation of A549 and H460 cells. Overall, these compounds are valuable tools for elucidating And1 biology, and their special spatial conformation make them promising candidates for future optimisation studies.

Cullin-RING Ligase 4 in Cancer: Structure, Functions, and Mechanisms

Cullin-RING ligase 4 (CRL4) has attracted enormous attentions because of its extensive regulatory roles in a wide variety of biological and pathological events, especially cancer-associated events. CRL4 exerts pleiotropic effects by targeting various substrates for proteasomal degradation or changes in activity through different internal compositions to regulate diverse events in cancer progression. In this review, we summarize the structure of CRL4 with manifold compositional modes and clarify the emerging functions and molecular mechanisms of CRL4 in a series of cancer-associated events.

Bazedoxifene analogs as potential WDHD1 degraders and antitumor agents: Synthesis, evaluation and molecular dynamics simulation studies

DNA repair is strongly associated with tumor resistance to radiotherapy and chemotherapy. WD repeat and HMG-box DNA binding protein 1 (WDHD1) is a key adaptor for homologous recombination repair of DNA, and its overexpression is relevant to the poor prognosis of many tumor patients. We previously have identified and validated bazedoxifene (BZA), which had 60% inhibitory rate on WDHD1 in MCF7 cells at 10 μM, from the Food and Drug Administration-approved compound library. Here, we initially established the binding model of BZA, synthesized and evaluated eight BZA analogs. Further, we detailed the use of molecular dynamics simulations to provide insights into the basis for activity against WDHD1. This binding mode will be instructive for the development of new WDHD1 degraders.

Integrative bioinformatics analysis of WDHD1: a potential biomarker for pan-cancer prognosis, diagnosis, and immunotherapy

BACKGROUND

Although WD repeat and high-mobility group box DNA binding protein 1 (WDHD1) played an essential role in DNA replication, chromosome stability, and DNA damage repair, the panoramic picture of WDHD1 in human tumors remains unclear. Hence, this study aims to comprehensively characterize WDHD1 across 33 human cancers.

METHODS

Based on publicly available databases such as TCGA, GTEx, and HPA, we used a bioinformatics approach to systematically explore the genomic features and biological functions of WDHD1 in pan-cancer.

RESULTS

WDHD1 mRNA levels were significantly increased in more than 20 types of tumor tissues. Elevated WDHD1 expression was associated with significantly shorter overall survival (OS) in 10 tumors. Furthermore, in uterine corpus endometrial carcinoma (UCEC) and liver hepatocellular carcinoma (LIHC), WDHD1 expression was significantly associated with higher histological grades and pathological stages. In addition, WDHD1 had a high diagnostic value among 16 tumors (area under the ROC curve [AUC] > 0.9). Functional enrichment analyses suggested that WDHD1 probably participated in many oncogenic pathways such as E2F and MYC targets (false discovery rate [FDR] < 0.05), and it was involved in the processes of DNA replication and DNA damage repair (p.adjust < 0.05). WDHD1 expression also correlated with the half-maximal inhibitory concentrations (IC50) of rapamycin (4 out of 10 cancers) and paclitaxel (10 out of 10 cancers). Overall, WDHD1 was negatively associated with immune cell infiltration and might promote tumor immune escape. Our analysis of genomic alterations suggested that WDHD1 was altered in 1.5% of pan-cancer cohorts and the "mutation" was the predominant type of alteration. Finally, through correlation analysis, we found that WDHD1 might be closely associated with tumor heterogeneity, tumor stemness, mismatch repair (MMR), and RNA methylation modification, which were all processes associated with the tumor progression.

CONCLUSIONS

Our pan-cancer analysis of WDHD1 provides valuable insights into the genomic characterization and biological functions of WDHD1 in human cancers and offers some theoretical support for the future use of WDHD1-targeted therapies, immunotherapies, and chemotherapeutic combinations for the management of tumors.

WD Repeat and HMG Box DNA Binding Protein 1: An Oncoprotein at the Hub of Tumorigenesis and a Novel Therapeutic Target

WD repeat and HMG-box DNA binding protein 1 (WDHD1) is a highly conserved gene from yeast to humans. It actively participates in DNA replication, playing a crucial role in DNA damage repair and the cell cycle, contributing to centromere formation and sister chromosome segregation. Notably, several studies have implicated WDHD1 in the development and progression of diverse tumor types, including esophageal carcinoma, pulmonary carcinoma, and breast carcinoma. Additionally, the inhibitor of WDHD1 has been found to enhance radiation sensitivity, improve drug resistance, and significantly decrease tumor cell proliferation. This comprehensive review aims to provide an overview of the molecular structure, biological functions, and regulatory mechanisms of WDHD1 in tumors, thereby establishing a foundation for future investigations and potential clinical applications of WDHD1.

And-1 Coordinates with the FANCM Complex to Regulate Fanconi Anemia Signaling and Cisplatin Resistance

The Fanconi anemia (FA) pathway is essential for repairing DNA interstrand crosslinks (ICL). ICLs induce stalled DNA replication forks and trigger activation of the FA pathway by promoting recruitment of the FANCM/FAAP24/MHF complex to ICL sites. Given that stalled replication forks are proximal to ICL sites, fork-associated proteins may coordinate with FA factors to rapidly sense ICLs for activation of FA signaling. Here we report that And-1, a replisome protein, is critical for activation of the FA pathway by sensing ICL-stalled forks and recruiting the FANCM/FAAP24 complex to ICLs. In response to ICLs, And-1 rapidly accumulated at ICL-stalled forks in a manner dependent on ataxia telangiectasia and Rad3-related protein-induced phosphorylation at T826. And-1 phosphorylation triggered an intramolecular change that promoted the interaction of And-1 with FANCM/FAAP24, resulting in recruitment of the FANCM/FAAP24 complex to ICLs. Furthermore, p-T826 And-1 was elevated in cisplatin-resistant ovarian cancer cells, and activated And-1 contributed to cisplatin resistance. Collectively, these studies elucidate a mechanism by which And-1 regulates FA signaling and identify And-1 as a potential target for developing therapeutic approaches to treat platinum-resistant ovarian cancer.

SIGNIFICANCE

This work shows that phosphorylation of And-1 by ATR activates Fanconi anemia signaling at interstrand crosslink-stalled replication forks by recruiting the FANCM/FAAP24 complex, revealing And-1 as a potential therapeutic target in cancer.

The Involvement of WDHD1 in the Occurrence of Esophageal Cancer as a Downstream Target of PI3K/AKT Pathway

Esophageal cancer is one of the most common malignant tumors in the world, which is characterized by high incidence, strong invasiveness, high mortality, and poor prognosis. At present, the therapies include surgery, endoscopic resection, radiotherapy and chemotherapy, targeted therapy, and immunotherapy. The five-year survival rate of esophageal cancer has not been significantly improved, although the medical level has been continuously improved and the management and application of different therapies have been improved day by day. At present, an abnormal gene expression is still regarded as an important factor in the occurrence and development of esophageal cancer. WD repeat and HMG-box DNA binding protein 1(WDHD1), as a key gene, plays an important role in the occurrence of esophageal cancer. It is known that the protein encoded by WDHD1 is the downstream target of the PI3K/AKT pathway. When PI3Ks is activated by extracellular signals, PI(4,5)P2 on the inner side of the plasma membrane will be converted into PI(3,4,5)P3. Then, PI(3,4,5)P3 can be converted into PI(3,4)P2,PI(4)P and PI(3)P by dephosphorylation of some regulatory factors. PI(3,4,5)P3 recruited AKT to the plasma membrane and combined with its pH domain, resulting in conformational change of AKT. Subsequently, AKT was completely activated by PDK1 and PDK2 and begins to move to the cytoplasm and nucleus. In this process, AKT continuously phosphorylates downstream substrates. WDHD1, as a downstream target of AKT, is also phosphorylated and induces DNA replication. Besides the abnormal regulation of cells by other downstream targets of AKT, it also becomes a potential pathway that may eventually lead to the occurrence of esophageal cancer.