Alpha Thalassemia/Intellectual Disability X-Linked Deficiency Sensitizes Non-Small Cell Lung Cancer to Immune Checkpoint Inhibitors

Mutational variant allele frequency profile as a biomarker of response to immune checkpoint blockade in non-small cell lung Cancer

INTRODUCTION

Identifying new biomarkers for predicting immune checkpoint inhibitors (ICIs) response in non-small cell lung cancer (NSCLC) is crucial. We aimed to assess the variant allele frequency (VAF)-related profile as a novel biomarker for NSCLC personalized therapy.

METHODS

We utilized genomic data of 915 NSCLC patients via cBioPortal and a local cohort of 23 patients for model construction and mutational analysis. Genomic, transcriptomic data from 952 TCGA NSCLC patients, and immunofluorescence (IF) assessment with the local cohort supported mechanism analysis.

RESULTS

Utilizing the random forest algorithm, a 15-gene VAF-related model was established, differentiating patients with durable clinical benefit (DCB) from no durable benefit (NDB). The model demonstrated robust performance, with ROC-AUC values of 0.905, 0.737, and 0.711 across training (n = 313), internal validation (n = 133), and external validation (n = 157) cohorts. Stratification by the model into high- and low-score groups correlated significantly with both progression-free survival (PFS) (training: P < 0.0001, internal validation: P < 0.0001, external validation: P = 0.0066) and overall survival (OS) (n = 341) (P < 0.0001). Notably, the stratification system was independent of PD-L1 (P < 0.0001) and TMB (P < 0.0001). High-score patients exhibited an increased DCB ratio and longer PFS across both PD-L1 and TMB subgroups. Additionally, the high-score group appeared influenced by tobacco exposure, with activated DNA damage response pathways. Whereas, immune/inflammation-related pathways were enriched in the low-score group. Tumor immune microenvironment analyses revealed higher proportions of exhausted/effector memory CD8 + T cells in the high-score group.

CONCLUSIONS

The mutational VAF profile is a promising biomarker for ICI therapy in NSCLC, with enhanced therapeutic stratification and management as a supplement to PD-L1 or TMB.

ATRX is a predictive marker for endocrinotherapy and chemotherapy resistance in HER2-/HR+ breast cancer through the regulation of the AR, GLI3 and GATA2 transcriptional network

Drug resistance in breast cancer (BC) is a clinical challenge. Exploring the mechanism and identifying a precise predictive biomarker for the drug resistance in BC is critical. Three first-line drug (paclitaxel, doxorubicin and tamoxifen) resistance datasets in BC from GEO were merged to obtain 1,461 differentially expressed genes for weighted correlation network analysis, resulting in identifying ATRX as the hub gene. ATRX is a chromatin remodelling protein, therefore, ATRX-associated transcription factors were explored, thereby identifying the network of AR, GLI3 and GATA2. GO and KEGG analyses revealed immunity, transcriptional regulation and endocrinotherapy/chemotherapy resistance were enriched. Moreover, CIBERSORT revealed immunity regulation was inhibited in the resistance group. ssGSEA showed a significantly lower immune status in the ATRX-Low group compared to the ATRX-High group. Furthermore, the peaks of H3K9me3 ChIP-seq on the four genes were higher in normal tissues than in BC tissues. Notably, the frequency of ATRX mutation was higher than BRCA in BC. Moreover, depressed ATRX revealed worse overall survival and disease-free survival in the human epidermal growth factor receptor 2 (HER2)-/hormone receptor (HR)+ BC. Additionally, depressed ATRX predicted poor results for patients who underwent endocrinotherapy or chemotherapy in the HER2-/HR+ BC subgroup. A nomogram based on ATRX, TILs and ER exhibited a significantly accurate survival prediction ability. Importantly, overexpression of ATRX significantly inhibited the IC50 of the three first-line drugs on MCF-7 cell. Thus, ATRX is an efficient predictive biomarker for endocrinotherapy and chemotherapy resistance in HER2-/HR+ BC and acts by suppressing the AR, GLI3 and GATA2 transcriptional network.

AP-2δ Is the Most Relevant Target of AP-2 Family-Focused Cancer Therapy and Affects Genome Organization

Formerly hailed as "undruggable" proteins, transcription factors (TFs) are now under investigation for targeted therapy. In cancer, this may alter, inter alia, immune evasion or replicative immortality, which are implicated in genome organization, a process that accompanies multi-step tumorigenesis and which frequently develops in a non-random manner. Still, targeting-related research on some TFs is scarce, e.g., among AP-2 proteins, which are known for their altered functionality in cancer and prognostic importance. Using public repositories, bioinformatics tools, and RNA-seq data, the present study examined the ligandability of all AP-2 members, selecting the best one, which was investigated in terms of mutations, targets, co-activators, correlated genes, and impact on genome organization. AP-2 proteins were found to have the conserved "TF_AP-2" domain, but manifested different binding characteristics and evolution. Among them, AP-2δ has not only the highest number of post-translational modifications and extended strands but also contains a specific histidine-rich region and cleft that can receive a ligand. Uterine, colon, lung, and stomach tumors are most susceptible to AP-2δ mutations, which also co-depend with cancer hallmark genes and drug targets. Considering AP-2δ targets, some of them were located proximally in the spatial genome or served as co-factors of the genes regulated by AP-2δ. Correlation and functional analyses suggested that AP-2δ affects various processes, including genome organization, via its targets; this has been eventually verified in lung adenocarcinoma using expression and immunohistochemistry data of chromosomal conformation-related genes. In conclusion, AP-2δ affects chromosomal conformation and is the most appropriate target for cancer therapy focused on the AP-2 family.

Association of ATRX mutations with immunologically active characteristics in patients with MSI-prone tumors

OBJECTIVES

The role of DNA damage repair deficiency in improving immune checkpoint inhibitors (ICIs) efficacy has been widely recognized. Studies have confirmed the association of gene mutations in homologous recombination (HR) with an immune-activated microenvironment. Given the crucial role of the tumor microenvironment in ICIs response, our study aimed to identify specific HR gene mutations that influence the tumor microenvironment and thus serve as potential biomarkers for ICIs in tumors that are prone to occur with microsatellite instability (MSI) events (MSI-prone tumors).

METHODS

The multi-omics and clinical data of MSI-prone tumors were extracted from ICIs-treated and non-ICIs-treated cohorts. We depicted the mutation landscape of HR genes in MSI-prone tumors and identified the prognosis related HR gene mutations. We integrated multiple immunotherapy-related indicators by bioinformatics methods to characterize the anti-tumor immunity and tumor microenvironment.

RESULTS

ATRX, ARID1A, BRCA2 and ATM were the common top four frequently mutated HR genes in MSI-prone tumors, among which ATRX mutations were identified to have prognostic value for ICIs treatment. The bioinformatics analyses suggested that patients with ATRX mutilations (ATRX-mt) have enhanced anti-tumor immunity and inflamed tumor microenvironment in MSI-prone tumors. MSI-stratified analyses revealed the immunologically active features in both microsatellite instability-high (MSI-H) and non-MSI-H populations. There may exist a synergistic effect between ATRX mutations and MSI-H status in immune activation.

CONCLUSIONS

Our work found the association of ATRX mutations with immunologically active characteristics in MSI-prone tumors. The combined use of ATRX mutations and MSI-H status might have potential clinical utility for ICIs selection in MSI-prone tumors.

Effect of CRISPR/Cas9-Edited PD-1/PD-L1 on Tumor Immunity and Immunotherapy

Clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease9 (CRISPR/Cas9) gene editing technology implements precise programming of the human genome through RNA guidance. At present, it has been widely used in the construction of animal tumor models, the study of drug resistance regulation mechanisms, epigenetic control and innovation in cancer treatment. Tumor immunotherapy restores the normal antitumor immune response by restarting and maintaining the tumor-immune cycle. CRISPR/Cas9 technology has occupied a central position in further optimizing anti-programmed cell death 1(PD-1) tumor immunotherapy. In this review, we summarize the recent progress in exploring the regulatory mechanism of tumor immune PD-1 and programmed death ligand 1(PD-L1) based on CRISPR/Cas9 technology and its clinical application in different cancer types. In addition, CRISPR genome-wide screening identifies new drug targets and biomarkers to identify potentially sensitive populations for anti-PD-1/PD-L1 therapy and maximize antitumor effects. Finally, the strong potential and challenges of CRISPR/Cas9 for future clinical applications are discussed.

A novel anti-lung cancer agent inhibits proliferation and epithelial-mesenchymal transition

OBJECTIVE

To synthesize a novel chalcone-1,3,4-thiadiazole hybrid and investigate its anticancer effects against NCI-H460 cells.

METHODS

(E)-3-(4-bromophenyl)-1-(4-hydroxyphenyl)prop-2-en-1-one, 1,3-dibromopropane and 1,3,4-thiadiazole-2-thiol were used as chemical materials to synthesize compound ZW97. The NCI-H460 lung cancer cell line was selected to explore the antitumor effects of compound ZW97 in vitro and in vivo.

RESULTS

Compound ZW97 selectively inhibited cell proliferation against lung cancer cell lines NCI-H460, HCC-44 and NCI-H3122 with IC₅₀ values of 0.15 μM, 2.06 μM and 1.17 μM, respectively. ZW97 suppressed migration and the epithelial-mesenchymal transition process in NCI-H460 cells in a concentration-dependent manner. Based on the kinase activity results and docking analysis, compound ZW97 is a novel tyrosine-protein kinase Met (c-Met kinase) inhibitor. It also inhibited NCI-H460 cell growth in xenograft models without obvious toxicity to normal tissues.

CONCLUSIONS

Compound ZW97 is a potential c-Met inhibitor that might be a promising agent to treat lung cancer by inhibiting the epithelial-mesenchymal transition process.

Clinicopathological Significance of ATRX Expression in Nasopharyngeal Carcinoma Patients: A Retrospective Study

Background: Nasopharyngeal carcinoma (NPC) is the most common head and neck squamous cell carcinoma in south China. Radiation technology improves the local control rates in early NPC. However, the distant metastases are still the main cause of treatment failure. Thus, to find biomarkers for prognosis will help to enhance the survival of NPC. ATRX is a chromatin remodeling protein localized in the nucleus. Deletion or mutation of ATRX gene has been demonstrated in a variety of malignancies. However, the significance of ATRX expression in the prognosis of NPC remains unclear.

Methods: Tumor tissues from 227 NPC patients diagnosed in the Second Xiangya Hospital of Central South University from 2011 to 2016 were selected. Immunohistochemistry was used to detect the ATRX expression level of the tumor tissue. Chi-square test was used to analyze the relationship between ATRX expression and clinical characteristics such as age, sex, T stage, N stage and clinical stage. Kaplan-Meier method was used for survival analysis, and log-rank was used to compare the difference in survival rate.

Results: There were 53 patients with negative ATRX expression, accounting for 24.2% of the total group. ATRX expression was not significantly associated with age, sex, N stage, clinical stage, and progression-free survival (PFS) (P>0.05). However, patients with negative ATRX expression had earlier T staging (P=0.045) and a higher 5-year overall survival (84.9% vs 66.9%, P=0.022).

Conclusions: Loss of ATRX expression may contribute to better prognosis in patients with NPC.