Targeting cell-cycle machinery in cancer

The small molecule drug CBL0137 interferes with DNA damage repair and enhances the sensitivity of NK/T-Cell lymphoma to cisplatin

This study aimed to investigate the in vitro and in vivo antitumor effects and mechanisms of the small molecule anticancer drug CBL0137 in NK/T-cell lymphoma (NKTCL), as well as its efficacy when combined with chemotherapy or immunotherapy. Cell viability assays were performed to evaluate the inhibitory effect of CBL0137 on NKTCL cell proliferation in vitro. Flow cytometry was used to assess the effects of the drug on apoptosis and cell cycle progression. RNA sequencing (RNA-seq) was employed to explore the mechanism of action of CBL0137 in NKTCL, and Western blotting (WB) was used to validate the expression of related proteins. An in vivo xenograft model was used to confirm the antitumor activity of CBL0137. Additionally, immunohistochemistry analysis was conducted to further study tumor tissue. CBL0137 effectively inhibited the proliferation of NKTCL cells in vitro, induced apoptosis, and significantly blocked cell cycle progression. RNA-seq analysis revealed that CBL0137 exerts its antitumor effect primarily by interfering with DNA damage repair. In vivo experiments using xenografted mice confirmed the antitumor activity of CBL0137. CBL0137, when combined with PD-1 antibody, exhibits synergistic antitumor effects in mice, and its combination with cisplatin significantly enhances the sensitivity of NKTCL to cisplatin. CBL0137 inhibits DNA damage repair in NK/T-cell lymphoma and enhances its sensitivity to cisplatin.

Prognostic signature based on mitochondria- and angiogenesis-related genes associated with immune microenvironment of multiple myeloma

INTRODUCTION

Mitochondria and angiogenesis play key roles in multiple myeloma (MM) development, but their interrelated genes affecting MM prognosis are under-studied.

METHODS

We analyzed TCGA_MMRF and GSE4581 datasets to identify four genes - CCNB1, CDC25C, HSP90AA1, and PARP1 - that significantly correlate with MM prognosis, with high expression indicating poor outcomes.

RESULTS

A prognostic signature based on these genes stratified patients into high- and low-risk groups, with the latter showing better survival. The signature was validated as an independent prognostic factor. Biological function analysis revealed differences in cell cycle processes between risk groups, and immune microenvironment analysis showed distinct immune cell infiltration patterns.

CONCLUSION

This mitochondria- and angiogenesis-related prognostic signature could enhance MM prognosis assessment and offer new therapeutic insights.

Apoptosis and cell cycle arrest of bone marrow cells by green-synthesized silver but not albumin nanoparticles

Metallic nanoparticles (NPs) made by traditional means have a deleterious effect on bone marrow (BM) cells. Alternatively, green-synthesized NPs are cost-effective, ecofriendly, and may be less toxic. Also, albumin is a biocompatible blood protein involved in several physiological processes, employed in drug delivery without posing adverse effects, and is thought to be ideal NPs or coating for reducing the metallic NP's toxicity. We prepared albumin NPs (AlbNPs), biosynthesized silver NPs (AgNPs) using the metabolite of the Escherichia coli D8 strain and coated them with albumin (Ag/AlbNPs). These NPs were characterized and intraperitoneally administered to rats to compare their effect on rat BM cells. The flow cytometry results revealed that AgNPs significantly reduced viability, increased apoptosis, downregulated the antiapoptotic Bcl2 gene expression, and upregulated the apoptotic genes Bax and p53 in BM cells, while treatment with AlbNPs maintained these parameters. Principally, AgNPs caused significant DNA fragmentation, since all parameters observed by the comet assay (tail length, tail DNA content, tail moment, and olive moment) were significantly higher in AgNP-treated groups than in control and AlbNP-treated groups. Investigation of the cell cycle revealed that treatment with AgNP, but not AlbNPs, downregulated the expression of the regulatory genes Cdk2, Cdk4, and the cyclins A1 (Ccna1) and D1 (Ccnd1), which resulted in the arrest of the progression of the cell cycle at GO/G1, as demonstrated by flow cytometry. Coating AgNPs with albumin increased their size, and decreased their intracellular concentration, resulting in reduced apoptosis and cell cycle arrest. However, these results for the Ag/AlbNP-treated group were still not comparable to those treated with pure AlbNPs. In conclusion, in contrast to AlbNPs, green AgNPs are toxic to bone marrow cells. Their coating with albumin, however, reduces this toxicity. To avoid this metal NP toxicity, it is recommended to use compatible degradable NPs instead of metal NPs for medication delivery to BM.

TPX2 lactylation is required for the cell cycle regulation and hepatocellular carcinoma progression

Targeting protein for Xklp2 (TPX2) is critical for mitosis and spindle assembly because of its control of Aurora kinase A (AURKA). However, the regulation of TPX2 activity and its subsequent effects on mitosis and cancer progression remain unclear. Here, we show that TPX2 is lactylated at K249 in hepatocellular carcinoma (HCC) tumour tissues and that this process is regulated by the lactylase CBP and the delactylase HDAC1. Lactate reduction via either shRNAs targeting lactate dehydrogenase A or the lactate dehydrogenase A inhibitor GSK2837808A decreases the level of TPX2 lactylation. Importantly, TPX2 lactylation is required for the cell cycle regulation and tumour growth. Mechanistically, TPX2 lactylation disrupts protein phosphatase 1 (PP1) binding to AURKA, enhances AURKA T288 phosphorylation, and facilitates the cell cycle progression. Overall, our study reveals a previously unappreciated role of TPX2 lactylation in regulating cell cycle progression and HCC tumorigenesis, exposing an important correlation between metabolic reprogramming and cell cycle regulation in HCC.

Role of cell cycle-related gene SAC3 domain containing 1 as a potential target of nitidine chloride in hepatocellular carcinoma progression

BACKGROUND

Hepatocellular carcinoma (HCC) is at the forefront of the global spectrum of cancer incidence and mortality, with conventional therapies like tyrosine kinase inhibitors limited by resistance. Recent studies have highlighted the promising anticancer effects of nitidine chloride (NC) against HCC. SAC3 domain containing 1 (SAC3D1) is critical for centrosome replication and spindle formation. However, research on SAC3D1 in HCC and NC remains limited.

AIM

To investigate the mechanisms underlying SAC3D1’s role in HCC progression and evaluated its potential as a therapeutic target of NC.

METHODS

RNA sequencing (RNA-seq) identified SAC3D1 expression changes in HCC cells after NC treatment. Molecular docking was further employed to validate the direct binding between NC and SAC3D1. Additionally, HCC multicenter data (The Cancer Genome Atlas_GTEx, ArrayExpress), pathway analysis, Pearson correlation analysis and SAC3D1 in vitro knockdown experiments were integrated to explore the molecular mechanisms underlying SAC3D1's involvement in HCC progression.

RESULTS

RNA-seq showed that NC treatment significantly downregulated SAC3D1 expression [log₂(fold change) = - 0.95, P < 0.05], with molecular docking revealing that NC directly bound to SAC3D1 proteins (binding energy: -9.7 kcal/mol). Enrichment analysis showed that most pathways were closely related to the cell cycle. Pearson correlation analysis indicated that SAC3D1 and cell cycle genes were significantly positively correlated(correlation coefficient ≥ 0.3, P < 0.05). SAC3D1 knockdown inhibited HCC cell invasion, migration, and proliferation by arresting cells in the S and G2/M phases. Flow cytometry confirmed that after SAC3D1 knockdown, the early and total apoptosis percentage of HCC cells decreased, while the late apoptosis percentage increased.

CONCLUSION

As a potential target of NC, SAC3D1 may inhibit HCC progression through cell cycle regulation following its downregulation by NC.

Limocitrin induced cellular death through ERK pathways in human oral squamous cell cancer

This study sought to investigate the anticancer efficacy of limocitrin on two distinct human oral cancer cell lines. At first, we evaluated the effect of limocitrin on the proliferation of OSCC cells (SCC-9 and SCC-47) using MTT and colony formation assays. Limocitrin treatment increased cell cycle arrest at G2/M phase, induced caspase-related apoptosis (cleaved caspase-3, caspase-8, caspase-9 and PARP expression) in OSCC cells. Limocitrin treatment inhibited Bcl-2 and Bcl-XL and induced Bax, Bak expression in both SCC-9 and SCC-47 cell lines. Limocitrin treatment inhibited cyclin E1, E2, CDK2, CDK4, and CDK6 and increased p21 expression. Limocitrin also exhibited an inhibitory effect on the phosphorylation of AKT, ERK1/2 and JNK in a dose-dependent manner. Additionally, pretreatment of oral cancer cells with U0126 resulted in increased cleaved caspase-3 and caspase-8 and PARP expression. Furthermore, limocitrin treatment decreased XIAP, cIAP1, HSP27 protein expression than control group. Combined treatment with limocitrin and si-XIAP significantly increased cleaved PARP, caspase-3 and -8 expressions in SCC-9 cells. Overall, this evidence indicates that limocitrin may serve as an effective anticancer agent for the treatment of oral cancer.

AP2M1 is a prognostic marker associated with cell cycle arrest and the tumor immune microenvironment in acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogeneous clonal disease of hematopoietic progenitor cells and the most common malignant myeloid disease in adults. Although significant progress has been made in treatment, the outlook remains bleak, and new therapeutic targets need to be sought. AP-2 complex subunit mu (AP2M1) is a core component of the clathrin-mediated endocytic machinery, AP2M1 plays a critical role in cancer progression. However, its function in acute myeloid leukemia (AML) progression remains unclear. Our study reveals that AP2M1 is highly expressed in AML and is associated with poor prognosis. Mechanistic studies suggest that this effect may result through cell cycle arrest and is associated with the tumor microenvironment, and our findings suggest that AP2M1 is a potential oncogene and prognostic marker for AML.

Diallyl disulfide in oncotherapy: molecular mechanisms and therapeutic potentials

Garlic possesses a broad spectrum of medicinal properties, such as anti-cancer, antioxidant, anti-diabetic effects, and protective effects on the heart, nervous system, and liver. Diallyl disulfide (DADS), an oil-soluble organic sulfur-containing compound in garlic, has garnered attention in recent years for its demonstrated anti-cancer efficacy in various cancer types such as leukemia, breast cancer, hepatocellular carcinoma, stomach cancer, and prostate cancer. The anticancer properties of DADS are attributed to its ability to suppress cancer cell proliferation, impede invasion and metastasis, as well as induce apoptosis, promote differentiation, and facilitate cell cycle arrest. Although many literatures have reviewed the pharmacokinetics, molecular mechanisms of anti-cancer effects and some clinical trials of DADS, the specific mechanisms and clinical-translational therapeutic potentials have not been elucidated. This comprehensive review focuses on delineating the molecular mechanisms underlying the anticancer effects of DADS, with a particular emphasis on its potential utility as a therapeutic intervention in the clinical management of cancer, and analyzes the challenges and coping strategies faced in the application of DADS as an anti-cancer drug, pointing out the directions for scientific research.

Research Progress of Natural Compounds from Chinese Herbal Medicine in the Treatment of Melanoma

OPINION STATEMENT

Melanoma is a malignant tumor that originates from activated or genetically altered epidermal melanocytes, resulting from the interplay of genetic, somatic, and environmental factors. It is the fastest-growing malignancy among the Caucasian population and has a high mortality rate, second only to lung cancer. Current mainstream treatments have led to unavoidable drug resistance and toxic side effects despite improvements in efficacy and prognosis. Traditional Chinese Medicine is a significant component of complementary and alternative medicine, playing a vital role in cancer treatment. Natural compounds derived from Chinese herbal medicines offer notable advantages owing to their multimolecular, multitarget, and multipathway characteristics. These compounds exert anti-melanoma effects through various mechanisms, including antiproliferation, promotion of apoptosis, inhibition of metastasis, suppression of angiogenesis, modulation of autophagy, and enhancement of the immune response. Furthermore, combining natural compounds with mainstream antagonistic medicine not only enhances treatment efficacy but also significantly reverses multidrug resistance. This article discusses the specific mechanisms by which natural compounds combat melanoma and reviews the recent research advancements in this field. It also addresses the challenges faced in the widespread clinical application of these natural compounds in melanoma treatment and outlines the future directions for their development.

Exosomal delivery of rapamycin modulates blood-brain barrier penetration and VEGF axis in glioblastoma

Exosomes (Exos), nanosized membranous vesicles (30-160 nm), have been validated as an effective drug delivery system capable of traversing biological barriers. Mesenchymal stem cells (MSCs), due to their near-limitless self-renewal capabilities, provide a plentiful source of exosomes for clinical applications. In this study, we utilized an exosome-encapsulated rapamycin (Exo-Rapa) delivery strategy, which permits the use of smaller drug dosages to achieve effects typically seen with higher dosages, thus enhancing drug efficacy. Moreover, Exos can transport pharmaceuticals across the blood-brain barrier (BBB) to the brain, and further penetrate GL261 cells to exert their effects. Within the tumor microenvironment, Exo-Rapa is released more rapidly and efficiently at the tumor site. The acidic conditions in tumors accelerate the release of Exo-Rapa, a characteristic that may make it a promising targeted therapeutic in future cancer research. Additionally, a series of in vivo experiments have further demonstrated the permeability of Exo-Rapa across the BBB, enabling it to accumulate at tumor sites; it also ameliorates inflammatory responses in Glioblastoma multiforme (GBM) mouse models and enhances anti-tumor activity through the regulation of angiogenesis via the VEGF/VEGFRs axis. Our results indicate that MSC-derived exosomes are a potent therapeutic carrier for GBM, offering an effective strategy for enhancing drug delivery across the BBB and providing a scientific foundation for the use of exosomes in the treatment of GBM and other diseases.

Synergistic effects of abietic acid combined with doxorubicin on apoptosis induction in a human colorectal cancer cell line

Cancer is a significant global disease with high mortality and limited therapeutic options. Chemotherapy is a cancer treatment option; however, there are still issues, including severe side effects, inadequate response, and drug resistance. Abietic acid is a natural diterpene with diverse pharmacological properties and can be used for cancer treatment. Therefore, this study aimed to assess the anticancer efficacy of abietic acid in combination with doxorubicin, a highly clinically used chemotherapeutic agent. Biochemical investigations include initial viability assays, combination therapy using isobologram analysis, apoptosis and cell cycle assays, gene expression assay, ELISA analysis of protein expression, DNA fragmentation, and wound healing assays. The data showed that doxorubicin-abietic acid (DOX-AB) is an effective and safe anticancer combination for Caco-2 cells. DOX-AB had a high safety index with minimal cytotoxicity at the combination dose on normal WI-38 fibroblasts cells. DOX-AB significantly decreased the proliferation and viability of Caco-2 cells, with an increase in the apoptosis rate in the late stage and necrosis with cell cycle arrest at the G2/M phase. Significant changes in the expression of modulators related to apoptosis, inflammation, and epigenetics were observed in gene and protein levels. DOX-AB combination had more efficient anticancer activity than doxorubicin alone. This study suggested that the use of abietic acid in combination with doxorubicin is a promising treatment for colorectal cancer because it enhances doxorubicin activity at relatively low doses with minimal cytotoxicity and overcomes multidrug resistance in tumors; these findings merit further investigation.

Beyond the Transcript: Translating Non-Coding RNAs and Their Impact on Cellular Regulation

Non-coding RNAs (ncRNAs) constitute the majority of the human transcriptome and play diverse structural, catalytic, and regulatory roles. The ability of ncRNAs to be translated into functional peptides and microproteins expands our understanding of their regulatory potential beyond their established non-coding functions. Our comprehensive search identified 86 translating "non-coding" RNAs. While translating ncRNAs have traditionally been categorized as "peptide-encoding", in this study, we introduce a novel classification based on amino acid length, distinguishing their products as ncRNA encoded peptides (ncRNA-PEPs), which are less than 60 amino acids, or ncRNA encoded microproteins (ncRNA-MPs) ranging from 61 to 200 amino acids. These peptides and microproteins act as co-regulators in cell signaling, transcriptional regulation, and protein complex assembly, playing a role in both health and disease. We outline the molecular pathways by which ncRNA-PEPs and ncRNA-MPs could govern cell cycle progression, highlighting their influence on cell cycle transitions, oncogenic and tumor suppressor pathways, metabolic homeostasis, autophagy, and on key cell cycle regulators like PCNA, Rad18, and CDK-cyclin complexes. Furthermore, we highlight recent advancements in their detection and characterization, exploring their evolutionary origins, species-specific conservation, and potential therapeutic applications. Our findings underscore the emerging significance of ncRNA-PEPs and ncRNA-MPs as integral regulators of cellular processes, highlighting their functional versatility and opening promising avenues for further research and potential therapeutic applications.

RNF6 Inhibits Lung Adenocarcinoma Cell Proliferation by Promoting Cyclin D2 Degradation

The E3 ubiquitin ligase RING finger protein 6 (RNF6) has been widely recognized for its role in promoting tumorigenesis in multiple cancers. However, we found that it is downregulated in lung adenocarcinoma (LUAD), and the molecular rationale for this discrepancy remains unclear. In the present study, we find that RNF6, but not its ΔRING inactive form, inhibits LUAD cell proliferation and migration and sensitizes LUAD to chemotherapy. To understand the molecular mechanism, we utilize affinity purification/tandem mass spectrometry (MS-MS) to analyze RNF6-interacting proteins and find that cyclin D2 (CCND2), a key regulator of the G1-S transition in the cell cycle. RNF6 physically binds to CCND2 and mediates its K48-linked polyubiquitination and subsequent degradation. However, ΔRING RNF6 fails to mediate CCND2 for ubiquitination and degradation. Moreover, Thr280 is critically important for CCND2 stability. When Thr280 is mutated, CCND2 becomes more stable and less ubiquitinated by RNF6. Furthermore, RNF6 arrests LUAD cell cycle at the G1 phase by inhibiting the CCND2/phospho-Rb signaling pathway, which is consistent with decreased cell proliferation. Lastly, RNF6 curtails the growth of LUAD xenografts in vivo, associated with decreased CCND2 expression. Therefore, RNF6 is a novel E3 ligase of CCND2 and suppresses LUAD cell proliferation. Implications: This study reveals a novel regulation on cell-cycle transition in LUAD and suggests the RNF6/CCND2 axis may represent an alternative therapeutic target for the treatment of LUAD.

Assessment of in vitro assays and quantitative determination of selectivity and modality of inhibitors targeting the cell cycle regulating, oncogenic cyclin-dependent kinases

At the heart of cancer pathology lies the dysregulated cell cycle, which is often driven by aberrant activities of the cell cycle regulating, cyclin-dependent kinases (CDKs). Efforts to harness the therapeutic potential of modulating CDK activities have led to the development of inhibitors with tailored CDK selectivity. However, uniformity in the methods used to evaluate CDK inhibitor selectivity has been lacking and consequently, direct comparison and interpretation of selectivity profiles determined under different assay conditions is difficult. Determination of the inhibition modalities crucial to profiling selectivity of a CDK inhibitor requires thorough kinetic analysis carried out under comparable assay conditions. In this study, we employed a streamlined series of in vitro assays for profiling CDK inhibitors wherein intrinsic inhibition constants and cellular binding parameters were measured by using strategically designed enzymatic inhibition and complementary biophysical assays. Our findings demonstrate the effectiveness of this strategy in determining and quantitatively analyzing the selectivity and inhibition modality of a set of representative CDK inhibitors towards the major oncogenic, cell cycle CDKs. In addition, the assay results provide insights into the inhibitor-target interactions that extend beyond potency and selectivity.

MTA1-DT promotes endometrial cancer growth by modulating G2/M-related gene transcription via PURα

In recent years, patients with early endometrial cancer (EC) can achieve a good prognosis through surgery. However, advanced and recurrent cases have still posed significant therapeutic challenges. This study aimed to investigate the biological function of long non-coding RNAs (lncRNAs) in EC and elucidate its underlying molecular mechanism. Through quantitative reverse transcription polymerase chain reaction (RT-qPCR) analysis, functional assays in cell lines, and bioinformatics approaches, we identified lncRNA MTA1-DT as a novel oncogenic factor in EC progression. RNA-seq and RT-qPCR analysis demonstrated that MTA1-DT was significantly upregulated with a 5-fold increase in EC cell lines compared to normal controls. Functional studies revealed that MTA1-DT promoted cell proliferation and migration. Mechanistically, we demonstrated that MTA1-DT physically interacted with purine-rich element binding protein-alpha (PURα) and facilitated its nuclear translocation, thereby enhancing its transcription factor activity. This nuclear accumulation of PURα promoted the transcription of downstream G2/M related genes, particularly EGF, leading to accelerated tumor growth. Thus, these results indicate that MTA1-DT exerts its oncogenic effects in EC through regulation of the cell cycle. Our findings establish MTA1-DT as a promising therapeutic target for EC treatment and provide new insights into the molecular mechanisms underlying EC progression.

Exploring RNA binding proteins in hepatocellular carcinoma: insights into mechanisms and therapeutic potential

Hepatocellular carcinoma (HCC), the most prevalent type of primary liver cancer, is linked to elevated global incidence and mortality rates. Elucidating the intricate molecular pathways that drive the progression of HCC is imperative for devising targeted and effective therapeutic interventions. RNA-binding proteins (RBPs) serve as pivotal regulators of post-transcriptional processes, influencing various cellular functions. This review endeavors to provide a comprehensive analysis of the expression, function, and potential implications of RBPs in HCC. We discuss the classification and diverse roles of RBPs, with a particular focus on key RBPs implicated in HCC and their association with disease progression. Additionally, we explore the mechanisms by which RBPs contribute to HCC, including their impact on gene expression, cell proliferation, cell metastasis, angiogenesis, signaling pathways, and post-transcriptional modifications. Importantly, we examine the potential of RBPs as therapeutic targets and prognostic biomarkers, offering insights into their relevance in HCC treatment. Finally, we outline future research directions, emphasizing the need for further investigation into the functional mechanisms of RBPs and their clinical translation for personalized HCC therapy. This comprehensive review highlights the pivotal role of RBPs in HCC and their potential as novel therapeutic avenues to improve patient outcomes.

Mycobacterial antigen Ag85B restrains Hodgkin lymphoma tumor growth by inhibiting autophagy

Background

The growth of the B-cell lymphoma subtype, Hodgkin lymphoma (HL), is associated with increased autophagy. A mycobacterial antigen, Ag85, has been reported to inhibit cell autophagy under a variety of conditions. Whether Ag85 could inhibit autophagy in HL is unknown.

Methods

Lymph node samples from patients with HL and healthy controls were collected to assess proliferation and autophagy. The human HL cell line, L-428, was cultured and subjected to Ag85B treatment. Autophagy in L-428 cells was evaluated through western blotting analysis, immunohistochemistry, and transmission electron microscopy. Apoptosis in these cells was measured using flow cytometry and western blotting. The associated signaling pathways were also analyzed utilizing western blotting. The in vivo impact of Ag85B was studied using BALB/c Nude mice xenografted with L-428 cells.

Results

We observed increased proliferation and autophagy in primary lymphoma tissues of patients. Administration of Ag85B inhibited the proliferation and autophagy of HL cell lines. Moreover, Ag85B promoted apoptotic pathway activation in vitro, which might be associated with mitochondrial dysfunction. Mechanistically, Ag85B inhibits autophagy by activating the phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B/mechanistic target of rapamycin kinase (PI3K/AKT/mTOR) and mitogen-activated protein kinase (MAPK) pathways. Ag85B also inhibited lymphoma growth in mice xenografted with HL cell lines, but no potential toxicity was observed.

Conclusion

Altogether, these results suggest that Ag85B inhibits HL growth via autophagy regulation. Current treatments for HL are associated with adverse events; therefore, Ag85B-mediated autophagy inhibition might be a promising strategy in to treat HL.

Research Progress on the Structure-activity Relationship and Mechanism of Flavonoid Derivatives in the Treatment of Lung Cancer

Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related deaths worldwide. The difficulty in early diagnosis, combined with the tendency for tumor invasion and metastasis, creates significant challenges for current therapeutic approaches. Additionally, the pharmaceutical agents currently used to treat NSCLC often come with severe side effects and can lead to drug resistance. As a result, there is an urgent need to develop new therapeutic agents with fewer side effects that can effectively overcome resistance mechanisms. Flavonoids, a prominent class of natural compounds, have shown promise in preventing and treating various cancers. By structurally optimizing flavonoids, it is possible to enhance their anticancer activity and improve their pharmacokinetic properties. This article reviews the different mechanisms of action and structure-activity relationships (SARs) of flavonoid derivatives in treating NSCLC, aiming to provide a scientific foundation for developing new therapeutic agents.

Mycosubtilin Induces G1 Phase Block and Autophagy in Cervical Cancer HeLa Cells

Cyclic lipopeptides secreted by the probiotic bacterium Bacillus subtilis have attracted much attention due to their antitumor activities and low toxicity. However, the role of Mycosubtilin (Myco) in the prevention and treatment of cervical cancer remains unclear. In the present study, we conducted a systematic evaluation of Myco's anti-cervical cancer effects to identify its molecular mechanism of action using proteomics technology. The results reveal that Myco inhibited the growth of HeLa and SiHa cervical cancer cell lines in a dose-dependent (3-15 µg/mL) and time-dependent (12-48 h) manner and significantly reduced colony formation and migration in HeLa cells, highlighting its potential to suppress tumor spread. Moreover, autophagosome and autolysosome numbers were significantly increased after Myco treatment, and the expression of autophagy-related proteins was significantly modulated, suggesting that autophagy plays a role in its anti-cancer mechanism. Myco treatment also induced G1 phase cell cycle arrest in HeLa cells, as confirmed by proteomics analysis. Myco was shown to induce cell cycle arrest in HeLa cells by regulating the P53 pathway and autophagy-dependent cell death via the PI3K/AKT/mTOR signaling pathway, demonstrating its multidimensional effect on cervical cancer cell growths. Myco treatment significantly inhibited tumor growth in vivo in a nude mouse cervical cancer xenograft model, providing direct evidence of its potential as a therapeutic candidate for cervical cancer. Given its unique anti-cancer mechanism and significant therapeutic efficacy, Myco should be considered a promising therapeutic agent for cervical cancer.

Solid pancancer analysis reveals immune and hematopoietic stem cell and DNA damage repair signatures to distinguish different cancer subtypes

PURPOSE

Immunity, stemness, and DNA damage repair (DDR) are crucial for cancer development and therapy resistance. With advancements in multiomics technology, the exploration of cancers related to immunity, stemness, and the DDR has triggered interest, but the combination of these levels for analyzing multiple cancers remains insufficient.

METHODS

In this study, 9906 solid tumor samples from 31 TCGA cancer types were clustered on the basis of the enrichment levels of 13 gene sets associated with stemness, immunity, and DDR. Moreover, a soft ensemble model was constructed on the basis of the enrichment levels of these 13 gene sets to predict cancer subtypes via other omics data.

RESULTS

We identified four pancancer subtypes, termed C1, C2, C3, and C4, which presented distinct molecular and clinical features, including the immune microenvironment, stemness, genome instability, intratumor heterogeneity, methylation levels, tumor progression, sensitivity to chemotherapy and immunotherapy, and survival prognosis. The soft ensemble model validated this subtyping method in two breast cancer datasets (gene expression level), a pancancer proteomic dataset (protein expression level), and a pancancer cell line dataset (cell line gene expression level).

CONCLUSION

Our findings indicate that immune, stemness, and DDR signature-based subtyping offers new perspectives on cancer biology and holds promise for improving the clinical management of cancers.

'Cell knife' for cancer: the clinician's perspective

Boron Neutron Capture Therapy (BNCT), often referred to as the 'cell knife,' represents a binary, tumor-selective therapeutic modality that minimizes damage to surrounding healthy tissues. This review provides a comprehensive clinical perspective on BNCT, addressing the radiobiological mechanisms and summarizing related clinical trials, with a particular emphasis on glioma and head and neck cancers. Furthermore, the paper touches upon the synergistic potential of BNCT when integrated with other treatment modalities, such as proton and carbon ion radiotherapy, alternative neutron capture therapies, ultrasound, and immunotherapy. These combined approaches may offer promising avenues for future research, potentially enhancing the therapeutic index and expanding the applicability of BNCT in oncological practice.

Lysine-specific demethylase 1 controls key OSCC preneoplasia inducer STAT3 through CDK7 phosphorylation during oncogenic progression and immunosuppression

Oral squamous cell carcinoma (OSCC) progresses from preneoplastic precursors via genetic and epigenetic alterations. Previous studies have focused on the treatment of terminally developed OSCC. However, the role of epigenetic regulators as therapeutic targets during the transition from preneoplastic precursors to OSCC has not been well studied. Our study identified lysine-specific demethylase 1 (LSD1) as a crucial promoter of OSCC, demonstrating that its knockout or pharmacological inhibition in mice reversed OSCC preneoplasia. LSD1 inhibition by SP2509 disrupted cell cycle, reduced immunosuppression, and enhanced CD4+ and CD8+ T-cell infiltration. In a feline model of spontaneous OSCC, a clinical LSD1 inhibitor (Seclidemstat or SP2577) was found to be safe and effectively inhibit the STAT3 network. Mechanistic studies revealed that LSD1 drives OSCC progression through STAT3 signaling, which is regulated by phosphorylation of the cell cycle mediator CDK7 and immunosuppressive CTLA4. Notably, LSD1 inhibition reduced the phosphorylation of CDK7 at Tyr170 and eIF4B at Ser422, offering insights into a novel mechanism by which LSD1 regulates the preneoplastic-to-OSCC transition. This study provides a deeper understanding of OSCC progression and highlights LSD1 as a potential therapeutic target for controlling OSCC progression from preneoplastic lesions.

Analysis of tumor cell proliferation (Ki-67) and cell cycle regulator proteins in lung adenocarcinoma with different radiological subtypes

BACKGROUND

The prognosis of ground glass opacity featured lung adenocarcinomas (GGO-LUAD) is significantly better than that of solid nodule featured lung adenocarcinomas (SN-LUAD), but the underlying reasons remain unclear. Ki-67 and cell cycle regulator proteins are highly expressed in many cancers and linked to prognosis. This study aims to investigate their differential expression in LUAD with different radiological subtypes.

METHODS

Patients with resected pathological stage 0-III LUAD in our department between July 2019 and March 2022 were retrospectively reviewed. All included patients were divided into four groups based on different consolidation-to-tumour ratio (CTR), we focuses on evaluating the differential expression of Ki-67 and cell cycle regulatory proteins (CCNA2, CCNB1, CCND1, P16, P21, TOP2A, TP53, and pRb) in LUAD with different CTR.

RESULTS

A total of 481 patients were included, 108 in the pure ground glass opacity (PGGO, CTR = 0) group, 103 in the GGO-dominant (GGO-D, 0 < CTR ≤ 0.5) group, 74 in the SN-dominant (SN-D, 0.5 < CTR < 1) group, and 196 in the pure solid nodule (SN, CTR = 1) group. The expression of Ki-67 was significantly higher in elderly patients (P < 0.05), former or current smokers (P < 0.0001), males (P < 0.05), poorly differentiated tumors (P < 0.0001), and tumors with spread through air spaces (STAS) (P < 0.0001), and advanced stage tumors (P < 0.0001). Regardless of age, gender, smoking status and epidermal growth factor receptor (EGFR) mutation status, GGO-LUAD demonstrated significantly lower expression of Ki-67 compared to SN-LUAD. The expression of Ki-67 and cell cycle regulatory proteins (except P21) were significantly lower in the PGGO, GGO-D, SN-D than in the SN group. However, there was no significant difference in the expression of Ki-67 and cell cycle regulatory proteins among the PGGO, GGO-D, and SN-D groups.

CONCLUSIONS

GGO-LUAD demonstrated significantly lower expression of Ki-67 and cell cycle regulatory proteins compared to SN-LUAD, which may explain the reasons behind the excellent prognosis of GGO-LUAD.

Tumor Suppressors Condition Differential Responses to the Selective CDK2 Inhibitor BLU-222

Cyclin-dependent kinase 2 (CDK2) inhibitors have recently been developed and have entered clinical trials. Combination approaches can help broaden the use of therapeutic agents and establish more effective treatments. Here, we evaluated the selective CDK2 inhibitor BLU-222 for mechanisms of response in the context of ovarian and breast cancer models. Sensors of cellular CDK activity indicated that sensitivity to either CDK4/6 or CDK2 inhibition was related to the differential dependence on a single CDK for G1-S transition. Unlike CDK4/6 inhibitors, BLU-222 was able to robustly inhibit proliferation through cell-cycle inhibition in both G1 and G2 phases. However, it remained possible for cells to reenter the cell cycle upon drug withdrawal. The antiproliferative strength and impact on G1-S versus G2-M accumulation was mediated by the RB tumor suppressor. To broaden the sensitivity to CDK2 inhibition, combinatorial drug screens were performed that identified both synergistic (e.g., CDK4/6 inhibitors) and antagonistic (e.g., WEE1 inhibitors) relationships. Models that were exceptionally sensitive to CDK2 inhibition displayed coordinate expression of cyclin E1 and P16INK4A, an endogenous CDK4/6 inhibitor. Functional studies demonstrated that P16INK4A and CDK4/6 activity were key mediators of sensitivity to BLU-222. Clinical gene and protein expression analyses revealed a positive correlation between cyclin E1 and P16INK4A and identified that ∼25% of ovarian cancers exhibited coordinate expression of cyclin E, P16INK4A, and RB, indicative of strong sensitivity to CDK2 inhibition. Together, this work advances a precision strategy for the use of CDK2 inhibitors in the context of ovarian and breast cancers. Significance: The CDK2-specific inhibitor BLU-222 shows preclinical efficacy in breast and ovarian cancer with select determinants of response and holds promise in combinatorial strategies. See related article by House and colleagues, p. 1297.

Targeting KIF18A triggers antitumor immunity and enhances efficiency of PD-1 blockade in colorectal cancer with chromosomal instability phenotype

Colorectal cancer with chromosomal instability (CIN+) phenotype is immunosuppressive and refractory to immune checkpoint blockade (ICB) therapy. Recently, KIF18A is found to be a mitotic vulnerability in chromosomally unstable cancers, but whether targeting KIF18A affects antitumor immunity in CIN+ colorectal cancer is unknown. In our study, western blot, cell viability assay, transwell migration and invasion assays, flow cytometry, animal model, immunohistochemistry (IHC) staining, reverse transcription-quantitative PCR (RT-qPCR) and ELISA assay were conducted to evaluate the potential function of KIF18A in CIN+ colorectal cancer. We found that KIF18A inhibition by short hairpin RNAs (ShRNAs) or small inhibitor AM-1882 suppressed proliferation, migration, invasion and tumor growth and metastasis of CIN+ colorectal cancer cells in vitro and in vivo. Moreover, targeting KIF18A disrupted cell-cycle progression and induced G2/M arrest in CIN+ colorectal cancer cells. In addition, KIF18A inhibition promoted immune infiltration and activation in CIN+ colorectal tumors. KIF18A inhibition suppressed proliferation of Tregs and increased infiltration and activation of cytotoxic CD8+ T cells in CIN+ colorectal tumors. Mechanically, KIF18A inhibition stimulated type I IFN signaling and cGAS-STING activation in CIN+ colorectal tumors. Finally, targeting KIF18A enhanced PD-1 blockade efficiency in CIN+ colorectal tumors through T cells. Our data elucidated a novel role of KIF18A in antitumor immunity of CIN+ colorectal cancer.

Innovative dual-gene delivery platform using miR-124 and PD-1 via umbilical cord mesenchymal stem cells and exosome for glioblastoma therapy

Addressing the challenges of identifying suitable targets and effective delivery strategies is critical in pursuing therapeutic solutions for glioblastoma (GBM). This study focuses on the therapeutic potential of microRNA-124 (miR-124), known for its tumor-suppressing properties, by investigating its ability to target key oncogenic pathways in GBM. The results reveal that CDK4 and CDK6-cyclin-dependent kinases that promote cell cycle progression-are significantly overexpressed in GBM brain samples, underscoring their role in tumor proliferation and identifying them as critical targets for miR-124 intervention. However, delivering miRNA-based therapies remains a major obstacle due to the instability of RNA molecules and the difficulty in achieving targeted, efficient delivery. To address these issues, this research introduces an innovative, non-viral dual-gene delivery platform that utilizes umbilical cord mesenchymal stem cells (UMSCs) and their exosomes to transport miR-124 and programmed cell death protein-1 (PD-1). The efficacy of this dual-gene delivery system was validated using an orthotopic GBM model, which closely mimics the tumor microenvironment seen in patients. Experimental results demonstrate that the UMSC/miR-124-PD-1 complex and its exosomes successfully induce apoptosis in GBM cells, significantly inhibiting tumor growth. Notably, these treatments show minimal cytotoxic effects on normal glial cells, highlighting their safety and selectivity. Moreover, the study highlights the immunomodulatory properties of UMSC/miR-124-PD-1 and its exosomes, enhancing the activation of immune cells such as T cells and dendritic cells, while reducing immunosuppressive cells populations like regulatory T cells and myeloid-derived suppressor cells. The orchestrated dual-gene delivery system by UMSCs and exosomes showcased targeted tumor inhibition and positive immune modulation, emphasizing its potential as a promising therapeutic approach for GBM.

Juglone-Bearing Thiopyrano[2,3-d]thiazoles Induce Apoptosis in Colorectal Adenocarcinoma Cells

Colorectal cancer is a major global health challenge, with current treatments limited by toxicity and resistance. Thiazole derivatives, known for their bioactivity, are emerging as promising alternatives. Juglone (5-hydroxy-1,4-naphthoquinone) is a naturally occurring compound with known anticancer properties, and its incorporation into thiopyrano[2,3-d]thiazole scaffolds may enhance their therapeutic potential. This study examined the cytotoxicity of thiopyrano[2,3-d]thiazoles and their effects on apoptosis in colorectal cancer cells. Les-6547 and Les-6557 increased the population of ROS-positive HT-29 cancer cells approximately 10-fold compared with control cells (36.3% and 38.5% vs. 3.8%, respectively), potentially contributing to various downstream effects. Elevated ROS levels were associated with cell cycle arrest, inhibition of DNA biosynthesis, and reduced cell proliferation. A significant shift in the cell cycle distribution was observed, with an increase in S-phase (from 17.3% in the control to 34.7% to 51.3% for Les-6547 and Les-6557, respectively) and G2/M phase (from 24.3% to 39.9% and 28.8%). Additionally, Les-6547 and Les-6557 inhibited DNA biosynthesis in HT-29 cells, with IC50 values of 2.21 µM and 2.91 µM, respectively. Additionally, ROS generation may initiate the intrinsic apoptotic pathway. Les-6547 and Les-6557 activated both intrinsic and extrinsic apoptotic pathways, demonstrated by notable increases in the activity of caspase 3/7, 8, 9, and 10. This study provides a robust basis for investigating the detailed molecular mechanisms of action and therapeutic potential of Les-6547 and Les-6557.

Chemical Probes for Studying the Eukaryotic Translation Initiation Factor 4E (eIF4E)-Regulated Translatome in Cancer

The dysregulation of translation is a hallmark of cancer that enables rapid changes in the cell proteome to shape oncogenic phenotypes that promote tumor survival. The predominant signaling pathways leading to dysregulation of translational control in cancer are the PI3K-AKT-mTORC1, RAS-RAF-MAPK, and MYC pathways, which all converge on eukaryotic translation initiation factor 4E (eIF4E), an RNA-binding protein that binds to the m7GpppX cap structure at the 5' end of mRNAs to initiate cap-dependent translation. eIF4E is the rate-limiting factor of translation initiation, and its overexpression is known to drive oncogenic transformation, progression, and chemoresistance across many cancers, establishing it as an attractive therapeutic target. Over the last several decades, significant efforts have been made to inhibit eIF4E through the development of mechanistically distinct small-molecule inhibitors that both directly and indirectly act on eIF4E to prevent cap-dependent translation initiation. These inhibitors can serve as powerful chemical tools to improve our understanding of the mechanisms of cap-dependent translation in cancer and to ultimately predict specific cancers that may benefit from eIF4E-targeted therapeutics. This review discusses the progress made in the development of different classes of small-molecule eIF4E inhibitors, the challenges that remain, and their potential as chemical probes to elucidate the complexities of cap-dependent translation in cancer.

Targeting cell cycle arrest in breast cancer by phytochemicals from Caryto urens L. fruit ethyl acetate fraction: in silico and in vitro validation

BACKGROUND

Caryota urens, also known as Shivjata, has been documented in ancient Indian texts for its therapeutic benefits, addressing conditions from seminal weakness to gastric ulcers. This study aims to investigate its contemporary medicinal potential in treating breast cancer.

OBJECTIVES

The study focuses on exploring the therapeutic potential of Caryota urens fruit against breast cancer, specifically targeting cell cycle genes CDK1, CDC25A, and PLK1 through bioinformatics, network pharmacology, and in vitro validation.

MATERIALS AND METHODS

Using mass spectrometry and nuclear magnetic resonance (NMR), 60 key phytoconstituents from Caryota urens fruit were identified. Bioinformatics analysis, integrating Gene Cards and GEO databases, 15,474 breast cancer-associated genes focusing on the HR+/HER2-subtype were identified. Molecular docking and qPCR validated the interactions of key phytoconstituents, particularly Episesamin, with CDK1, CDC25A, and PLK1. In vitro studies were conducted on the MCF7 cell line, supplemented by ROC and survival analyses to evaluate diagnostic and therapeutic potential.

RESULTS

The bioinformatics analysis identified CDK1, CDC25A, and PLK1 as pivotal genes regulating cell cycle progression and breast cancer tumorigenesis. Network pharmacology and in vitro studies indicated that phytoconstituents, especially Episesamin, downregulated these genes in breast cancer cells. Molecular docking and qPCR confirmed these interactions, and ROC and survival analyses underscored their diagnostic and therapeutic significance.

CONCLUSIONS

This study suggests that Caryota urens fruit extract, particularly Episesamin, may inhibit breast cancer metastasis by downregulating CDK1, CDC25A, and PLK1, offering promising new strategies for targeting the cell cycle in breast cancer and emphasizing the value of integrating bioinformatics with experimental methods in cancer research.

PRR11 Promotes Bladder Cancer Growth and Metastasis by Facilitating G1/S Progression and Epithelial-Mesenchymal Transition

BACKGROUND

Although Proline-rich Protein 11 (PRR11) abnormalities are closely associated with carcinogenesis, the precise mechanism of bladder cancer remains unclear. Here, we sought to elucidate the molecular mechanisms of PRR11 in bladder cancer.

METHODS

We performed differential expression analysis of PRR11 from the TCGA and GEO databases, followed by validation with clinical samples. Survival analysis was employed to assess the correlation between PRR11 and patient prognosis. The effects of PRR11 on bladder cancer cells were examined through both in vitro and in vivo experiments. Additionally, Gene Set Enrichment Analysis (GSEA) was used to predict the downstream pathways associated with PRR11, which were further validated through subsequent experiments.

RESULTS

PRR11 is upregulated in bladder cancer and could lead to poor prognosis. In vitro, PRR11 promoted tumor cell proliferation; in vivo, it promoted subcutaneous tumor growth. PRR11 knockdown inhibited its oncogenic function. On the molecular level, PRR11 promotes tumor metastasis by inducing Epithelial-mesenchymal Transition (EMT). GSEA suggests that PRR11 is strongly linked to the cell cycle, and silencing of PRR11 can achieve anti-tumor effects by inhibiting CCNE and blocking the G1/S phase transition.

CONCLUSIONS

Our study demonstrates that silencing PRR11 can arrest the malignant progression of bladder cancer by inhibiting EMT and blocking the G1/S transition. Targeting PRR11 may provide new insights for targeting cell cycle therapy.

Proteogenomic characterisation of primary oral cancer unveils extracellular matrix remodelling and immunosuppressive microenvironment linked to lymph node metastasis

Oral squamous cell carcinoma (OSCC) is an increasingly prevalent malignancy worldwide. This study aims to understand molecular alterations associated with lymph node metastasis of OSCC in order to improve treatment strategies. We analysed a cohort of 46 patients with primary OSCC, including 10 with lymph node metastasis and 36 without. Using a comprehensive multi-omics approach - encompassing genomic, transcriptomic, proteomic, epigenetic, single-cell, and spatial analyses - we integrated data to delineate the molecular landscape of OSCC in the context of lymph node metastasis. Our genomic analysis identified significant mutations in key genes within the MAPK, TGF-β and WNT signalling pathways, which are essential for tumour development. The proteogenomic analysis highlighted pathways critical for lymph node dissemination and factors contributing to an immunosuppressive tumour microenvironment. Elevated levels of POSTN were found to reorganise the extracellular matrix (ECM), interact with TGF-β, disrupt cell cycle regulation and suppress the immune response by reducing VCAM1 activity. Integrated analyses of single-cell and spatial transcriptome data revealed that cancer-associated fibroblasts (CAFs) secrete TGF-β1/2, promoting cancer cell metastasis through epithelial-mesenchymal transition (EMT). Our integrated multi-omics analysis provides a detailed understanding of molecular mechanisms driving lymph node metastasis of OSCC. These insights could lead to more precise diagnostics and targeted treatments. This article is protected by copyright. All rights reserved.

RNA m5C methylation mediated by Ybx1 ensures hematopoietic stem and progenitor cell expansion

Hematopoietic stem and progenitor cells (HSPCs) undergo rapid transcriptional transitions among distinct cell states and functional properties during development, but the underlying molecular mechanism is largely unknown. Here, we characterize the mRNA m5C landscape of developing HSPCs in zebrafish and found that m5C modification is essential for HSPC expansion through maintaining mRNA stability. Deletion of the m5C reader, Y-box binding protein 1 (Ybx1), significantly inhibits the proliferation of HSPCs in zebrafish and mice. Mechanistically, Ybx1 recognizes m5C-modified mRNAs and maintains the stability of cell-cycle-related transcripts, thereby ensuring proper HSPC expansion. This study reveals the critical role of Ybx1-mediated mRNA m5C modification in developmental hematopoiesis and provides new insights and epitransciptomic strategies for optimizing HSPC expansion.

CDK4/6 inhibitors upregulate cIAP1/2, and Smac mimetic LCL161 enhances their antitumor effects in cholangiocarcinoma cells

Cholangiocarcinoma (CCA) is a highly aggressive bile duct cancer with a poor prognosis and high mortality rates, primarily due to the lack of early diagnosis and effective treatments. We have shown that cyclin D and CDK4/6, key regulators of cell cycle progression, are highly expressed in CCA patients. Moreover, high levels of cyclin D, CDK4, and CDK6 are associated with shorter survival in CCA patients, suggesting that cyclin D and CDK4/6 might be potential targets for CCA therapy. However, we have demonstrated that CDK4/6 inhibitor palbociclib monotherapy is less effective in CCA cells. We have identified Cellular Inhibitor of Apoptosis Proteins 1 and 2 (cIAP1/2), NF-κB target genes that their expression is associated with shorter survival in CCA patients, as potential key regulators of the CDK4/6 inhibitor response. We showed that palbociclib, a CDK4/6 inhibitor, increases phosphorylated p65 and its nuclear translocation, resulting in cIAP1/2 upregulation in CCA cells. Therefore, we hypothesized that the combination of a cIAP1/2 antagonist and a CDK4/6 inhibitor might enhance the CDK4/6 inhibitor response. Interestingly, combined treatment with the Smac mimetic LCL161, a cIAP1/2 antagonist, and palbociclib synergistically inhibits cell proliferation and induces cell death in both 2D monolayer and 3D spheroid CCA cultures. We further showed that this combination treatment has less effect on non-tumor cholangiocytes and human peripheral blood mononuclear cells (PBMCs). Our findings demonstrate for the first time that the combined treatment of Smac mimetics and CDK4/6 inhibitors is a promising novel targeted therapy for CCA patients.

Targeted Inhibition of CHD1L by OTI-611 Reprograms Chemotherapy and Targeted Therapy-Induced Cell Cycle Arrest and Suppresses Proliferation to Produce Synergistic Antitumor Effects in Breast and Colorectal Cancer

The second and third most frequently diagnosed cancers worldwide are breast (2.3 million new cases) and colorectal (1.9 million new cases), respectively. Although advances in cancer therapies and early detection have improved the overall survival of patients, patients still develop resistance or cancer recurrence. Thus, the development of novel therapies that can affect multiple mechanisms of drug resistance and cell survival is ideal for the treatment of advanced and metastatic cancers. CHD1L is a novel oncogenic protein involved in regulating chromatin remodeling, DNA damage repair, epithelial-mesenchymal transition (EMT), and programmed cell death via PARthanatos. Herein, we assess in real-time how the CHD1L inhibitor (CHD1Li) OTI-611 modulates cell cycle progression in Colo678, SUM149PT, and SW620 cell lines. By utilizing a cell cycle reporter, we tracked the real-time cell cycle progression of cancer cells treated with OTI-611 alone and in combination with standard-of-care (SOC) therapies. Our results indicate that OTI-611 causes G1 phase cell cycle arrest through a CHD1L-mediated mechanism that regulates Cyclin D1 expression and localization. As a result of this mechanism, OTI-611 can reprogram the cell cycle effects of other antitumor agents to modulate and arrest cells in G1 when used in combination, including agents commonly known to arrest cells in the G2/M phase. Therefore, we conclude that OTI-611-induced G1 arrest represents a critical component of its unique mechanism of action, contributing significantly to its anticancer activity.

Inhibition of Cyclin D1 by Novel Biguanide Derivative YB-004 Increases the Sensitivity of Bladder Cancer to Olaparib via Causing G0 / G1 Arrest

Bladder cancer (BC) is the 10th most common type of tumor worldwide, and recently approved immunotherapies and FGFR inhibitors have been shown to improve the prognosis of only a very limited subset of BC patients. Thus, the quest for more effective drugs remains an urgent priority for improving the quality of life of more BC patients. Previously, we demonstrated that a novel biguanide YB-004 has potent antitumor activity. In this study, we found that the novel biguanide YB-004 interrupts the cell cycle by reducing the expression of cyclin D1, causing G0/G1 phase arrest, and suppresses homologous recombination (HR) by inhibiting Rad51, thereby increasing DNA damage and blocking BC cell proliferation. Interestingly, our results further revealed that cell accumulation in the S and G2/M phases is the main reason why HR-proficient BC cells are not sensitive to olaparib, as these phases are conducive to HR activation and DNA repair. Thus, YB-004 increased the sensitivity of BC cells to olaparib by reversing the cell cycle changes and HR activation caused by olaparib. Taken together, these findings suggest that the combination of YB-004 with olaparib has great potential for the clinical treatment of HR-proficient BC.

Ficus caricaleaves extract-loaded PLGA nanoparticles: preparation, characterization, andin vitroanticancer activity on TFK-1 cell line

Ficus caricaextract (FCe) is a natural herb that has received a lot of interest in cancer treatment due to its potential anticancer activities against various malignancies. However, due to FCe's low bioavailability and low solubility, its clinical use as an anti-cancer medicine is constrained. The current study aimed to prepare FCe-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) for cancer treatment. Prepared NPs were characterized by UV-v is spectroscopy, dynamic light scattering, zeta potential, and transmission electron microscopy. The results showed that the spherical FCe-loaded PLGA NPs had a particle size of 162 ± 0.7 nm, a polydispersity index of 0.08 ± 0.005, and a zeta potential of -4.7 ± 0.6 mV. The encapsulation and loading efficiency were found to be 56 ± 2.3% and 14 ± 1.5%, respectively. A drug release study indicated a diffusion-based release profile. Cytotoxicity was evaluated on the extrahepatic bile duct carcinoma (TFK-1) cell line, which showed that both free FCe and corresponding FCe concentrations in NPs were cytotoxic. Cell cycle analysis showed that the FCe arrests the cells in G0/G1 phase, and the cell arrest rate is higher in FCe-loaded NPs compared to free form. A phototoxicity study also showed that the phototoxicity of FCe-loaded PLGA NPs was time-dependent and enhanced in comparison to free FCe. The study's results demonstrated that FCe-encapsulated PLGA NPs are promising for cancer therapy as a phyto- and phototherapeutic agent-based system.

A novel gemcitabine analog as a potential anticancer agent: synthesis and in-vitro evaluation against pancreatic cancer

Gemcitabine (Gem) is approved for use in pancreatic cancer chemotherapy. However, Gem undergoes rapid metabolism in the blood, producing an inactive metabolite. Due to this rapid metabolism, the effective dose of Gem is high, thereby predisposing patients to severe adverse effects. This study aimed to improve Gem's metabolic and therapeutic stability by modifying the amine group (4-NH2) with hydroxylamine to form 4-N-hydroxylGem hydrochloride (GemAGY). Micro-elemental analysis and Nuclear Magnetic Resonance (NMR) were used to characterize GemAGY, and its anticancer activity was investigated against MiaPaCa-2, BxPC-3, and PANC-1 pancreatic cancer cell lines. The GemAGY metabolic stability was evaluated in human liver microsomal solution. In the 2D cytotoxicity assay, the IC50 values of GemAGY-treated MiaPaCa-2, PANC-1, and BxPC-3 cells were significantly lower when compared to GemHCl-treated cultures. More so, in 3D spheroid assay results, GemAGY IC50 values were found to be 9.5 ± 1.1 µM and 12.6 ± 1.0 µM when compared to GemHCl IC50 values of 24.1 ± 1.6 µM and 30.2 ± 1.8 µM in MiaPaCa-2 and PANC-1 cells, respectively. GemAGY was stable, with 60% remaining intact after 2 hours of digestion in microsomal enzymes, compared to GemHCl, which had less than 45% remaining intact after 30 minutes. GemAGY-treated MiaPaCa-2 and PANC-1 cells at 3.12 and 6.25 μM concentrations demonstrated a significantly reduced cell migration towards the wound area compared to the GemHCl-treated cultures at the same concentrations. Further, GemAGY-treated MiaPaCa-2 cells significantly increased the expression of p53 and BAX compared to GemHCl-treated cells. GemAGY demonstrated significant anticancer activity and improved metabolic stability compared to GemHCl and is most likely to have potential anticancer activity against pancreatic cancer.

HNF1A-AS1 promotes oral squamous cell carcinoma progression via regulating miR-138/CDK6 pathway

The action and the latent mechanism of HNF1A-AS1 in oral squamous cell carcinoma (OSCC) development were probed. Levels of HNF1A-AS1, microRNA-138 (miR-138) and Cyclin-dependent kinase 6 (CDK6) were examined. In vitro assays were conducted using SCC-4 and SCC15 cells derived from a human SCC of the tongue of a 55-year-old male. In vivo assay was performed by establishing OSCC mouse models. An elevated HNF1A-AS1 was detected in OSCC, and down-expressed HNF1A-AS1 inhibited migration and invasion, and promoted apoptosis in OSCC cells in vitro. HNF1A-AS1 targeted miR-138 to positively regulate the expression of CDK6, a target of miR-138. Knockdown of miR-138 attenuated the action of HNF1A-AS1 silencing on OSCC cell malignant phenotypes. Besides that, overexpression of CDK6 weakened miR-138-mediated anti-cancer functions. Moreover, HNF1A-AS1 knockdown restrained OSCC growth in nude mice. HNF1A-AS1 promoted OSCC tumorigenesis via miR-138/CDK6 pathway, indicating the potential molecular contribution of HNF1A-AS1 on OSCC pathogenesis.

An update understanding of stemness and chemoresistance of prostate cancer

INTRODUCTION

Globally, prostate cancer (CaP) is a leading cause of death and disability among men and a substantial public health burden. Despite advancements in cancer treatment, chemoresistance remains a significant issue in cancer therapy, accounting for the majority of patient relapses and poor survival. Cancer stem cells (CSCs) are considered the main cause of cancer recurrence, chemoresistance, and poor survival of patients. These CSCs acquire stemness and chemoresistance by certain mechanisms such as enhanced DNA repair processes, increased expression of drug efflux pumps, resistance to apoptosis, and altered cell cycle and tumor microenvironment (TME).

AREA COVERED

We cover the latest developments in this field and give an overview of future research directions.

EXPERT OPINION

CSCs show dysregulation of several signaling pathways, mostly related to conferring chemoresistance phenotype, such as high drug efflux, apoptotic resistance, quiescent cell cycle, tumor microenvironment, and DNA repair. There are several research articles published on this topic. However, still, this field warrants further investigations to identify the therapeutic molecule that can either chemosensitize CSCs or kill them effectively. This can only be possible when we know the complete mechanisms to comprehend the fundamental causes of cancer stemness and therapy resistance.

Discrete vulnerability to pharmacological CDK2 inhibition is governed by heterogeneity of the cancer cell cycle

Cyclin dependent kinase 2 (CDK2) regulates cell cycle and is an emerging target for cancer therapy. There are relatively small numbers of tumor models that exhibit strong dependence on CDK2 and undergo G1 cell cycle arrest following CDK2 inhibition. The expression of P16INK4A and cyclin E1 determines this sensitivity to CDK2 inhibition. The co-expression of these genes occurs in breast cancer patients highlighting their clinical significance as predictive biomarkers for CDK2-targeted therapies. In cancer models that are genetically independent of CDK2, pharmacological inhibitors suppress cell proliferation by inducing 4N cell cycle arrest and increasing the expressions of phospho-CDK1 (Y15) and cyclin B1. CRISPR screens identify CDK2 loss as a mediator of resistance to a CDK2 inhibitor, INX-315. Furthermore, CDK2 deletion reverses the G2/M block induced by CDK2 inhibitors and restores cell proliferation. Complementary drug screens define multiple means to cooperate with CDK2 inhibition beyond G1/S. These include the depletion of mitotic regulators as well as CDK4/6 inhibitors cooperate with CDK2 inhibition in multiple phases of the cell cycle. Overall, this study underscores two fundamentally distinct features of response to CDK2 inhibitors that are conditioned by tumor context and could serve as the basis for differential therapeutic strategies in a wide range of cancers.

Unraveling Mechanism and Enhancing Selectivity of a RuII-bis-bipyridyl-morphocumin Complex with RAFT-Generated Glycopolymer Exploiting Warburg Effect in Cancer

The Warburg effect, which generates increased demand of glucose in cancer cells is a relatively underexplored phenomenon in existing commercial drugs to enhance uptake in cancer cells. Here, we present a chemotherapeutic strategy employing a Ru(II)-bis-bipyridyl-morphocumin complex (2) encapsulated in a self-assembling glucose-functionalized copolymer P(G-EMA-co-MMA) (where G=glucose; MMA=methyl methacrylate; EMA=ethyl methacrylate), designed to exploit this effect for enhanced selectivity in cancer treatment. The P(G-EMA-co-MMA) polymer, synthesized via reversible-addition fragmentation chain transfer (RAFT) polymerization, has a number average molecular weight (Mn,NMR) of 8000 g/mol. Complex 2, stable in aqueous media, selectively releases a cytotoxic, lysosome-targeting compound, morphocumin, in the presence of excess hydrogen peroxide (H₂O₂), a reactive oxygen species (ROS) prevalent in tumor microenvironments. Additionally, complex 2 promotes ROS accumulation, which may further enhance morphocumin release through a synergistic domino effect. Comparative studies reveal that 2 outperforms its curcumin Ru(II) complex (1) analog in solution stability, organelle specificity, and cellular mechanisms. Both 1 and 2 exhibit phototherapeutic effects under low-intensity visible light, but their chemotoxicity significantly increases with incubation time in the dark, highlighting the superior chemotherapeutic efficacy of the O,O-coordinating Ru(II) ternary polypyridyl complexes. Complex 2 induces apoptosis via the intrinsic pathway and shows a 9-fold increase in selectivity for pancreatic cancer cells (MIA PaCa-2) over non-cancerous HEK293 cells when encapsulated in the glucose-conjugated polymer (DP@2). Glucose deprivation in the culture medium further enhances drug efficacy by an additional 5-fold. This work underscores the potential of glucose-functionalized polymers and ROS-responsive Ru(II) complexes in targeted cancer therapy.

LRP5 enhances glioma cell proliferation by modulating the MAPK/p53/cdc2 pathway

Background: Glioma is a malignant neoplasm with generally poor prognosis and the treatment options and effective drugs are very limited. LRP5, a member of the low-density lipoprotein receptor (LDLR) gene family, has been reported to regulate the progression of various cancers such as gastric and colorectal cancer. However, the function of LRP5 in glioma has not been elucidated. The objective of this study is to explore the influence of LRP5 in glioma cell proliferation and its potential molecular mechanisms. Methods: LRP5 expression in glioma was assessed through bioinformatics analysis, and validation was conducted using clinical glioma tissues. Glioma cell lines with reduced LRP5 expression were established through RNA interference. A series of experiments such as cell proliferation assay, flow cytometry analysis, and Western blotting were used to determine the role of LRP5 in glioma cell proliferation, cell cycle progression, and the underlying mechanisms. Results: LRP5 was found to be upregulated in glioma tissues and exhibited significant variations across various subtypes of glioblastoma (GBM). When differentiating between normal individuals and glioma patients, the area under the receiver operating characteristic curve (ROC) for LRP5 was determined to be 0.981. Downregulating the expression of LRP5 in glioma cells can weaken their proliferative ability and reduce the number of cell colonies. There were more cells arrested in the G2/M phase of the cell cycle. The protein levels of phospho-p53 (p-p53), p21Cip1, and phospho-cdc2 (p-cdc2) were elevated. Moreover, LRP5 down-regulation suppressed the phosphorylation of the mitogen-activated protein kinase (MAPK) family members, JNK and p38 MAPK. Consistent results with those mentioned above can be achieved by using an LRP5 antagonist named DKK-1. Conclusion: This research has identified that LRP5 may promote glioma proliferation by influencing the G2/M transition and the activation of the MAPK/p53/cdc2 pathways, suggesting its value as a potential molecular target for glioma diagnosis and treatment.

In vitro and in vivo evidence of the antineoplastic activity of quercetin against endothelial cells transformed by Kaposi's sarcoma-associated herpesvirus G protein-coupled receptor

Quercetin (QUE) is a natural flavonoid with well-known anticancer capabilities, although its effect on viral-induced cancers is less studied. Kaposi's sarcoma (KS) is a viral cancer caused by the human herpesvirus-8, which, during its lytic phase, expresses a constitutively activated viral G protein-coupled receptor (vGPCR) able to induce oncogenic modifications that lead to tumor development. The aim of this work was to investigate the potential effect of QUE on in vitro and in vivo models of Kaposi's sarcoma, developed by transforming endothelial cells with the vGPCR of Kaposi's sarcoma-associated herpesvirus. Initially, the antiproliferative effect of QUE was determined in endothelial cells stably expressing the vGPCR (vGPCR cells), with an IC50 of 30 μM. Additionally, QUE provoked a decrease in vGPCR cell viability, interfered with the cell cycle progression, and induced apoptosis, as revealed by annexin V/PI analysis and caspase-3 activity. The presence of apoptotic bodies and disorganized actin filaments was observed by SEM and phalloidin staining. Furthermore, tumors from vGPCR cells were induced in nude mice, which were treated with QUE (50 or 100 mg/kg/d) resulting in retarded tumor progression and reduced tumor weight. Notably, neither kidney nor liver damage was observed, as indicated by biochemical parameters in serum. In conclusion, this study suggests for the first time that QUE exhibits antineoplastic activity in both in vitro and in vivo models of KS, marking a starting point for further investigations and protocols for therapeutic purpose.

High-Efficiency Gold Nanoaggregates for NIR LED-Driven Sustained Mild Photothermal Therapy Achieving Complete Tumor Eradication and Immune Enhancement

For millennia, humans have harnessed thermal energy to treat cancer. However, delivering energy to tumor tissues in traditional hyperthermia remains a significant challenge. Nanotechnology has revolutionized this approach, enabling nanomaterials to target tumors precisely and act as internal heat sources. Nanomaterial-based photothermal therapy employs nano-photothermal agents to absorb near-infrared light and convert it into heat, offering non-invasive, highly controllable, and specific treatment for solid tumors. Nonetheless, achieving complete tumor eradication, preventing recurrence, and ensuring safety continue to be major concerns. To address these issues, sustained mild photothermal therapy (smPTT) is proposed, utilizing gold nanoaggregates (AuNAs) with a high photothermal conversion efficiency (92.8%) in combination with a single irradiation of low-power (∼0.1 W cm- 2) sustained LED light. This method achieved complete tumor eradication in animal models, with no recurrence over long-term (>180 days) monitoring. This strategy provides superior therapeutic effects compared to mild photothermal therapy and higher safety than high-temperature photothermal therapy. Additionally, it induces a strong immune response and immune memory, crucial for preventing tumor recurrence and metastasis. This novel approach to photothermal therapy may significantly impact clinical applications for shallow tumor treatment and offer new avenues for immunotherapy.

Hematological toxicity of cyclin-dependent kinase 4/6 inhibitors in patients with breast cancer: a network meta-analysis and pharmacovigilance study

OBJECTIVES

We aimed to evaluate and compare the risk of hematological adverse events (AEs) associated with CDK4/6 inhibitors using data from randomized controlled trials (RCTs) and Food and Drug Adverse Event Reporting System (FAERS) database.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched for RCTs related to abemaciclib, palbociclib, and ribociclib. A network meta-analysis (NMA) was conducted to compare the risks of hematological AEs, and a disproportionality analysis was performed to detect signals of hematological AEs.

RESULTS

16 RCTs comprising 16,350 breast cancer patients were included. Palbociclib and ribociclib had similar risks for hematological AEs, except a higher risk of grade 3-4 leukopenia observed with palbociclib (risk ratio [RR]: 7.84, 95% confidence interval [95%CI]: 1.33-41.28). Abemaciclib had a higher risk of anemia than both ribociclib (grade 1-4: RR: 2.23, 95% CI: 1.25 - 3.96; grade 3-4: RR: 3.52, 95% CI: 1.59 - 8.11) and palbociclib (grade 1-4: RR: 1.65, 95%CI: 1.03 - 2.59), but a lower risk of grade 3-4 of both leukopenia (RR: 0.12, 95%CI: 0.02 - 0.49) and neutropenia (RR: 0.15, 95%CI: 0.04 - 0.52) compared with palbociclib. Signals indicating occurrence of leukopenia, neutropenia, anemia, and thrombocytopenia were identified for three CDK4/6 inhibitors.

CONCLUSION

Abemaciclib, palbociclib, and ribociclib showed significant but inconsistent hematological toxicity risks.

Ferritin-Based Supramolecular Assembly Drug Delivery System for Aminated Fullerene Derivatives to Enhance Tumor-Targeted Therapy

Owing to their attractive antitumor effects, aminated fullerene derivatives are emerging as promising therapeutic drugs for cancer. However, their in vivo applications are severely limited due to cation toxicity. To address this problem, human heavy chain ferritin (HFn), possessing natural biocompatibility is utilized, to develop a novel supramolecular assembly drug delivery system. Specifically, tetra[4-(amino)piperidin-1-yl]-C60 (TAPC) is selected as the representative aminated fullerene, and a layer-by-layer assembly strategy is designed to controllably assemble TAPC with the negatively charged HFn into a hierarchical coassembly (H@T@H) via electrostatic interactions and hydrogen bonds. In this ordered multilayer structure, the surface displayed HFn endows the inner TAPC with biocompatibility, tumor-targeting and blood-brain barrier crossing ability. Additionally, the electrostatic assembly mode enables the acid-responsive disassembly of H@T@H to release TAPC in lysosomes. In the orthotopic glioma mouse model, the HFn-assembled TAPC (H@T@H) shows higher brain accumulation and a stronger inhibitory effect on glioma than polyethylene glycol (PEG)-coated TAPC. Moreover, in an experimental metastasis mouse model, H@T@H have significant preventive and therapeutic effects on tumor metastasis. Encouragingly, the ferritin-based supramolecular assembly strategy has been proven to have broad applicability for various aminated fullerene derivatives, showing promising potential for tackling the in vivo delivery challenges of cationic drugs.

An open-label, phase IB/II study of abemaciclib with paclitaxel for tumors with CDK4/6 pathway genomic alterations

BACKGROUND

Disruption of cyclin D-dependent kinases (CDKs), particularly CDK4/6, drives cancer cell proliferation via abnormal protein phosphorylation. This open-label, single-arm, phase Ib/II trial evaluated the efficacy of the CDK4/6 inhibitor, abemaciclib, combined with paclitaxel against CDK4/6-activated tumors.

PATIENTS AND METHODS

Patients with locally advanced or metastatic solid tumors with CDK4/6 pathway aberrations were included. Based on phase Ib, the recommended phase II doses were determined as abemaciclib 100 mg twice daily and paclitaxel 70 mg/m2 on days 1, 8, and 15, over 4-week-long cycles. The primary endpoint for phase II was the overall response rate (ORR). The secondary endpoints included the clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS), and safety. Tissue-based next-generation sequencing and exploratory circulating tumor DNA analyses were carried out.

RESULTS

Between February 2021 and April 2022, 30 patients received abemaciclib/paclitaxel (median follow-up: 15.7 months), and 27 were included in the efficacy analysis. CDK4/6 amplification (50%) and CCND1/3 amplification (20%) were common activating mutations. The ORR was 7.4%, with two partial responses, and the CBR was 66.7% (18/27 patients). The median OS and PFS were 9.9 months [95% confidence interval (CI) 5.7-14.0 months] and 3.5 months (95% CI 2.6-4.3 months), respectively. Grade 3 adverse events (50%, 21 events) were mainly hematologic. Genetic analysis revealed a 'poor genetic status' subgroup characterized by mutations in key signaling pathways (RAS, Wnt, PI3K, and NOTCH) and/or CCNE amplification, correlating with poorer PFS.

CONCLUSION

Abemaciclib and paclitaxel showed moderate clinical benefits for CDK4/6-activated tumors. We identified a poor genetic group characterized by bypass signaling pathway activation and/or CCNE amplification, which negatively affected treatment response and survival. Future studies with homogeneous patient groups are required to validate these findings.

Decoding oral cancer: insights from miRNA expression profiles and their regulatory targets

Oral cancer (OC) is a prevalent malignancy with high mortality rates, largely attributed to late diagnosis and limited therapeutic advancements. MicroRNAs (miRNAs), as critical regulators of gene expression, have emerged as key players in modulating plethora of cellular mechanisms. This study analyzed miRNA and gene expression profiles in OC using publicly available datasets from the Gene Expression Omnibus (GEO) to explore their roles in tumorigenesis. A total of 23 differentially expressed miRNAs (DEmiRs) and 1,233 differentially expressed genes (DEGs) were identified. Functional annotation and pathway enrichment analyses highlighted significant involvement of DEmiRs and their target genes in cell cycle-related processes, including enrichment in the nucleus, transcription factor activity, regulation of nucleosides, nucleotide and nucleic acids, cell growth and/or maintenance, mitotic cell cycle, mitotic M-M/G1 phases an DNA replication. Furthermore, different signaling cascades such as IGF signaling, PDGF signaling and LKB1 signaling and PLK1 signaling pathways were also found associated with DEmiR-related regulation of OC progression. Protein-protein interaction (PPI) network analysis identified key molecular hubs associated with DEmiR and DEGs in OC. Notably, most of these hub genes such as NEK2, NDC80, NUF2, PLK1, SMAD2, TP53, TPX2, TTK, UBE2C, WDHD1, WTAP, YWHAZ are directly or indirectly associated with cell cycle progression, underscoring the role of DEmiRs in driving tumor proliferation and survival in OC via dysregulating cell cycle. This study offers insights into the molecular mechanisms underlying OC and highlights miRNAs as potential biomarkers and therapeutic targets to disrupt the cancerous cell cycle and improve treatment outcomes.

Phase I trial of hydroxychloroquine to enhance palbociclib and letrozole efficacy in ER+/HER2- breast cancer

Endocrine therapy with CDK4/6 inhibitors is standard for estrogen receptor-positive, HER2-negative metastatic breast cancer (ER+/HER2- MBC), yet clinical resistance develops. Previously, we demonstrated that low doses of palbociclib activate autophagy, reversing initial G1 cell cycle arrest, while high concentrations induce off-target senescence. The autophagy inhibitor hydroxychloroquine (HCQ) induced on-target senescence at lower palbociclib doses. We conducted a phase I trial (NCT03774472 registered in ClinicalTrials.gov on 8/20/2018) of HCQ (400, 600, 800 mg/day) with palbociclib (75 mg/day continuous) and letrozole, using a 3 + 3 design. Primary objectives included safety, tolerability, and determining the recommended phase 2 dose (RP2D) of HCQ. Secondary objectives included tumor response and biomarker analysis. Fourteen ER+/HER2- MBC patients were evaluable [400 mg (n = 4), 600 mg (n = 4), 800 mg (n = 6)]. Grade 3 adverse events (AEs) included hematological (3 at 800 mg), skin rash (2 at 600 mg), and anorexia (1 at 400 mg), with no serious AEs. The best responses were partial (2), stable (11), and progression (1). Tumor reductions ranged from 11% to 30%, with one 55% increase. The two partial responders sustained tumor size reductions of 30% to 55% over an extended treatment period, lasting nearly 300 days. Biomarker analysis in responders demonstrated significant decreases in Ki67, Rb, and nuclear cyclin E levels and increases in autophagy markers p62 and LAMP1, suggesting a correlation between these biomarkers and treatment response. This phase I study demonstrated that HCQ is safe and well-tolerated and the RP2D was established at 800 mg/day with continuous low-dose palbociclib (75 mg/day) and letrozole (2.5 mg/day). These findings suggest that adding HCQ could potentially enhance the efficacy of low-dose palbociclib and standard letrozole therapy, pending verification in larger randomized studies.

MS4A15 gene expression as a prognostic marker for clinical outcomes in lung adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is the predominant histological subtype of lung cancer. In the past decade, various targeted drugs have prolonged the survival of LUAD patients. Unfortunately, not all LUAD patients can benefit from the current target agents. Although the membrane spanning 4-domains A15 (MS4A15) gene has been implicated in the progression of various cancers, its role in LUAD remains understudied. This study aimed to evaluate the role and potential mechanism of MS4A15 in the progression of LUAD.

Methods

The pan-cancer RNA sequencing and clinical data of LUAD patients, originally comprising data from The Cancer Genome Atlas and Genotypic Tissue Expression, were acquired from University of California Santa Cruz XENA (UCSC XENA). Additionally, the GSE116959 and GSE130779 data sets were retrieved from the Gene Expression Omnibus database. The Differential Expression analysis of Sequencing data version 2 (DESeq2) package was used to identify the differentially expressed genes. The ClusteProfiler package was used to perform the Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and gene set enrichment analyses. An immune cell infiltration analysis was conducted using the gene set variation analysis (GSVA) package. The expression level of MS4A15 was analyzed by the Wilcoxon rank-sum test. A logistic regression analysis was conducted to examine the correlation between the clinical pathological factors of LUAD patients and the high-low dichotomy of MS4A15. A receiver operating characteristic (ROC) curve analysis was employed to evaluate the effectiveness of MS4A15 as a biomarker for distinguishing LUAD patients from healthy individuals. A Kaplan-Meier analysis was conducted to examine the overall survival of LUAD patients based on MS4A15. All the bioinformatic results were obtained using R (version 3.6.2) package. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to validate the messenger RNA transcription level in vitro.

Results

MS4A15 expression was significantly more decreased in the tumor tissues from the LUAD patients than the normal adjacent samples. MS4A15 expression was positively correlated with various immune cell types, notably including mast cells (MCs), dendritic cells, and macrophages. Specifically, MS4A15 was most positively associated with MCs. Lower expression levels of MS4A15 in LUAD patients were correlated with a poorer pathologic stage and poorer primary therapy outcomes. The area under the curve of the ROC curve for MS4A15 effectiveness was 0.863. MS4A15 was validated to be more lowly expressed in the tumor tissues samples than the normal tissues samples in both the GSE116959 and GSE130779 data sets. The expression of MS4A15 was also significantly lower in the in A549 cells than the normal human bronchial epithelia cells.

Conclusions

Overall, MS4A15 emerged as a promising prognostic biomarker for LUAD and could serve as a potential target for the development of novel therapeutic interventions.