Novel Insights for Inhibiting Mutant Heterodimer IDH1wt-R132H in Cancer: An In-Silico Approach

Recent progress in emerging molecular targeted therapies for intrahepatic cholangiocarcinoma

Cholangiocarcinoma (CCA) is a diverse group of epithelial malignant tumors arising from the biliary tract, characterized by high molecular heterogeneity. It is classified into intrahepatic (iCCA) and extrahepatic CCA (eCCA) based on the location of the primary tumor. CCA accounts for approximately 15% of all primary liver cancers, with iCCA comprising 10-20% of all CCAs. iCCA is especially known for its characteristic aggressiveness and refractoriness, leading to poor prognosis. Despite the increasing global incidence and mortality rates, surgery remains the only available standard treatment approach for a subset (25%) of patients with early-stage, resectable iCCA. The paucity of effective systemic medical therapies restricts therapeutic options for patients with advanced or metastatic iCCA. In the past decade, advances in the understanding of the molecular complexity of these tumors have provided fruitful insights for the identification of promising new druggable targets and the development of feasible therapeutic strategies that may improve treatment outcomes for patients with iCCA. In this review, we aim to highlight critical up-to-date studies and medicinal chemistry aspects, focusing on novel targeted approaches utilizing promising candidates for molecular targeted therapy in iCCA. These candidates include aberrations in isocitrate dehydrogenase (IDH) 1/2, fibroblast growth factor receptor (FGFR), B-Raf proto-oncogene (BRAF), neurotrophic tyrosine receptor kinase (NTRK), human epidermal growth factor receptor 2 (HER2), and programmed cell death protein 1 (PD-1)/programmed cell death-ligand 1 (PD-L1). Furthermore, this review provides an overview of potential inhibitors aimed at overcoming acquired drug resistance in these actionable targets for iCCA.

In silico approaches for drug repurposing in oncology: a scoping review

Introduction: Cancer refers to a group of diseases characterized by the uncontrolled growth and spread of abnormal cells in the body. Due to its complexity, it has been hard to find an ideal medicine to treat all cancer types, although there is an urgent need for it. However, the cost of developing a new drug is high and time-consuming. In this sense, drug repurposing (DR) can hasten drug discovery by giving existing drugs new disease indications. Many computational methods have been applied to achieve DR, but just a few have succeeded. Therefore, this review aims to show in silico DR approaches and the gap between these strategies and their ultimate application in oncology. Methods: The scoping review was conducted according to the Arksey and O'Malley framework and the Joanna Briggs Institute recommendations. Relevant studies were identified through electronic searching of PubMed/MEDLINE, Embase, Scopus, and Web of Science databases, as well as the grey literature. We included peer-reviewed research articles involving in silico strategies applied to drug repurposing in oncology, published between 1 January 2003, and 31 December 2021. Results: We identified 238 studies for inclusion in the review. Most studies revealed that the United States, India, China, South Korea, and Italy are top publishers. Regarding cancer types, breast cancer, lymphomas and leukemias, lung, colorectal, and prostate cancer are the top investigated. Additionally, most studies solely used computational methods, and just a few assessed more complex scientific models. Lastly, molecular modeling, which includes molecular docking and molecular dynamics simulations, was the most frequently used method, followed by signature-, Machine Learning-, and network-based strategies. Discussion: DR is a trending opportunity but still demands extensive testing to ensure its safety and efficacy for the new indications. Finally, implementing DR can be challenging due to various factors, including lack of quality data, patient populations, cost, intellectual property issues, market considerations, and regulatory requirements. Despite all the hurdles, DR remains an exciting strategy for identifying new treatments for numerous diseases, including cancer types, and giving patients faster access to new medications.

Mutated Isocitrate Dehydrogenase (mIDH) as Target for PET Imaging in Gliomas

Gliomas are the most common primary brain tumors in adults. A diffuse infiltrative growth pattern and high resistance to therapy make them largely incurable, but there are significant differences in the prognosis of patients with different subtypes of glioma. Mutations in isocitrate dehydrogenase (IDH) have been recognized as an important biomarker for glioma classification and a potential therapeutic target. However, current clinical methods for detecting mutated IDH (mIDH) require invasive tissue sampling and cannot be used for follow-up examinations or longitudinal studies. PET imaging could be a promising approach for non-invasive assessment of the IDH status in gliomas, owing to the availability of various mIDH-selective inhibitors as potential leads for the development of PET tracers. In the present review, we summarize the rationale for the development of mIDH-selective PET probes, describe their potential applications beyond the assessment of the IDH status and highlight potential challenges that may complicate tracer development. In addition, we compile the major chemical classes of mIDH-selective inhibitors that have been described to date and briefly consider possible strategies for radiolabeling of the most promising candidates. Where available, we also summarize previous studies with radiolabeled analogs of mIDH inhibitors and assess their suitability for PET imaging in gliomas.

The immune regulation of BCL3 in glioblastoma with mutated IDH1

Background: Glioblastoma in the brain is the most malignant solid tumor with a poor prognosis. Screening critical targets and exploring underlying mechanisms will be a benefit for diagnoses and treatment. IDH1 mutation (R132) was used to distinguish glioblastoma grade and predict prognosis as a significant marker. However, the manner of IDH1 mutation regulating glioblastoma development was still unclear.

Methods: To study the function of IDH1 mutation, multi-type sequencing data (transcriptome, methylation and copy number variation) from the GEO and TCGA database were analyzed using bioinformatics techniques. The biological functions of IDH1 mutation (R132) would be comprehensively evaluated from the regulatory networks, tumor immune microenvironment and clinical relevance. Then the analysis result would be validated by experimental techniques.

Results: Compared with adjacent tissues, IDH1 was up-regulated in glioblastoma, which also positively correlated with the malignant degree and a poor prognosis. To further study the mechanism of mutated IDH1 (R132) function, 5 correlated genes (FABP5, C1RL, MIR155HG, CSTA and BCL3) were identified by different expression gene screening, enrichment analysis and network construction successively. Among them, the BCL3 was a transcription factor that may induce IDH1expression. Through calculating the correlation coefficient, it was found that in IDH1^mut glioblastoma, the dendritic cell infiltration was reduced which may result in a better prognosis. In addition, the level of IDH1, FABP5, C1RL, MIR155HG, CSTA and BCL3 might also influence lymphocytes infiltration (eg. CD4+ T cell) and chemokine expression (CXCL family).

Conclusions: IDH1 may participate in pathological mechanisms of glioblastoma via expression alteration or gene mutation. Furthermore, IDH1 mutation might improve prognosis via suppressing the expression of FABP5, C1RL, MIR155HG, CSTA and BCL3. Meanwhile, it was identified that BCL3 might perform similar immunomodulatory functions with IDH1 as an upstream transcript factor.