The inhibition of cyclin-dependent kinases (CDKs) is considered a promising strategy for cancer treatment due to their role in cell cycle regulation. However, CDK inhibitors with no selectivity among CDK families have not been approved. A CDK inhibitor with high selectivity for CDK4/6 exhibited significant treatment effects on breast cancer and has become a heavy bomb on the market. Subsequently, resistance gradually decreased the efficacy of selective CDK4/6 inhibitors in breast cancer treatment. In this review, we first introduce the development of selective CDK4/6 inhibitors and then explain the role of CDK2 activation in inducing resistance to CDK4/6 inhibitors. Moreover, we focused on the development of CDK2/4/6 inhibitors and selective CDK2 inhibitors, which will aid in the discovery of novel CDK inhibitors targeting the cell cycle in the future.
Humans ; Cell Cycle/drug effects* ; Protein Kinase Inhibitors/chemistry* ; Cyclin-Dependent Kinases/metabolism* ; Neoplasms/genetics* ; Antineoplastic Agents/pharmacology* ; Animals ; Breast Neoplasms/enzymology* ; Cyclin-Dependent Kinase 4/metabolism*

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a prevalent type of cancer with a high mortality rate in its late stages. One of the major challenges in OSCC treatment is the resistance to epidermal growth factor receptor (EGFR) inhibitors. Therefore, it is imperative to elucidate the mechanism underlying drug resistance and develop appropriate precision therapy strategies to enhance clinical efficacy. METHODS: To evaluate the efficacy of the combination of the Ca 2+ /calmodulin-dependent protein kinase II (CAMK2) inhibitor KN93 and EGFR inhibitors, we performed in vitro and in vivo experiments using two FAT atypical cadherin 1 ( FAT1 )-deficient (SCC9 and SCC25) and two FAT1 wild-type (SCC47 and HN12) OSCC cell lines. We assessed the effects of EGFR inhibitors (afatinib or cetuximab), KN93, or their combination on the malignant phenotype of OSCC in vivo and in vitro . The alterations in protein expression levels of members of the EGFR signaling pathway and SRY-box transcription factor 2 (SOX2) were analyzed. Changes in the yes-associated protein 1 (YAP1) protein were characterized. Moreover, we analyzed mitochondrial dysfunction. Besides, the effects of combination therapy on mitochondrial dynamics were also evaluated. RESULTS: OSCC with FAT1 mutations exhibited resistance to EGFR inhibitors treatment. The combination of KN93 and EGFR inhibitors significantly inhibited the proliferation, survival, and migration of FAT1 -mutated OSCC cells and suppressed tumor growth in vivo . Mechanistically, combination therapy enhanced the therapeutic sensitivity of FAT1 -mutated OSCC cells to EGFR inhibitors by modulating the EGFR pathway and downregulated tumor stemness-related proteins. Furthermore, combination therapy induced reactive oxygen species (ROS)-mediated mitochondrial dysfunction and disrupted mitochondrial dynamics, ultimately resulting in tumor suppression. CONCLUSION Combination therapy with EGFR inhibitors and KN93 could be a novel precision therapeutic strategy and a potential clinical solution for EGFR-resistant OSCC patients with FAT1 mutations.
Humans ; ErbB Receptors/metabolism* ; Mouth Neoplasms/metabolism* ; Cell Line, Tumor ; Animals ; Drug Resistance, Neoplasm/genetics* ; Cadherins/metabolism* ; Carcinoma, Squamous Cell/metabolism* ; Mice ; Mutation/genetics* ; Mice, Nude ; Protein Kinase Inhibitors/therapeutic use* ; Cetuximab/pharmacology* ; Afatinib/therapeutic use* ; Cell Proliferation/drug effects* ; Signal Transduction/drug effects*

Objective To investigate the effects of LBL-007, a novel fully human lymphocyte activation gene 3 (LAG-3) monoclonal antibody, in combination with programmed cell death protein 1 (PD-1) antibody, on the invasion, migration and proliferation of tumor cells, and to elucidate the underlying mechanisms. Methods Human lymphocyte cells Jurkat were co-cultured with A549 and MGC803 tumor cell lines and treated with the isotype control antibody human IgG, LBL-007, anti-PD-1 antibody BE0188, or tumor necrosis factor-alpha (TNF-α, the NF-κB signaling pathway agonist). Tumor cell proliferation was assessed using a colony formation assay; invasion was measured by Transwell^TM assay; migration was evaluated using a wound healing assay. Western blotting was employed to determine the expression levels of NF-κB pathway-related proteins: IκB inhibitor kinase alpha (Ikkα), phosphorylated Ikkα (p-IKKα), NF-κB subunit p65, phosphorylated p65 (p-p65), NF-κB Inhibitor Alpha (IκBα), phosphorylated IκBα (p-IκBα), matrix metalloproteinase 9 (MMP9), and MMP2. Results Compared with the control and IgG isotype groups, LBL-007 and BE0188 significantly reduced tumor cell proliferation, invasion, and migration. They also decreased the phosphorylation of p-IKKα, p-p65 and p-IκBα, and the expression of MMP9 and MMP2 of tumor cells in the co-culture system. The combined treatment of LBL-007 and BE0188 enhanced inhibitory effects. Treatment with the NF-κB signaling pathway agonist TNF-α reversed the suppressive effects of LBL-007 and BE0188 on tumor cell proliferation, invasion, migration, and NF-κB signaling. Conclusion LBL-007 and anti-PD-1 antibody synergistically inhibit the invasion, migration, and proliferation of A549 and MGC803 tumor cells by blocking the NF-κB signaling pathway.
Humans ; Cell Proliferation/drug effects* ; Cell Movement/drug effects* ; Signal Transduction/drug effects* ; NF-kappa B/metabolism* ; Neoplasm Invasiveness ; Antibodies, Monoclonal/pharmacology* ; Programmed Cell Death 1 Receptor/antagonists & inhibitors* ; Cell Line, Tumor ; Antigens, CD/immunology* ; Lymphocyte Activation Gene 3 Protein ; A549 Cells ; I-kappa B Kinase/metabolism* ; Jurkat Cells ; Matrix Metalloproteinase 9/metabolism*

Ovarian cancer is the most lethal malignancy affecting the female reproductive system. Pharmacological inhibitors targeting CDK4/6 have demonstrated promising efficacy across various cancer types. However, their clinical benefits in ovarian cancer patients fall short of expectations, with only a subset of patients experiencing these advantageous effects. This study aims to provide further clinical and biological evidence for antineoplastic effects of a CDK4/6 inhibitor (TQB4616) in ovarian cancer and explore underlying mechanisms involved. Patient-derived ovarian cancer organoid models were established to evaluate the effectiveness of TQB3616. Potential key genes related to TQB3616 sensitivity were identified through RNA-seq analysis, and TRIM4 was selected as a candidate gene for further investigation. Subsequently, co-immunoprecipitation and GST pull-down assays confirmed that TRIM4 binds to hnRNPDL and promotes its ubiquitination through RING and B-box domains. RIP assay demonstrated that hnRNPDL binded to CDKN2C isoform 2 and suppressed its expression by alternative splicing. Finally, in vivo studies confirmed that the addition of siTRIM4 significantly improved the effectiveness of TQB3616. Overall, our findings suggest that TRIM4 modulates ubiquitin-mediated degradation of hnRNPDL and weakens sensitivity to CDK4/6 inhibitors in ovarian cancer treatment. TRIM4 may serve as a valuable biomarker for predicting sensitivity to CDK4/6 inhibitors in ovarian cancer.
Humans ; Female ; Ovarian Neoplasms/pathology* ; Animals ; Tripartite Motif Proteins/genetics* ; Mice ; Cyclin-Dependent Kinase 4/antagonists & inhibitors* ; Cell Line, Tumor ; Cyclin-Dependent Kinase 6/antagonists & inhibitors* ; Protein Kinase Inhibitors/pharmacology* ; Ubiquitin/metabolism* ; Xenograft Model Antitumor Assays ; Ubiquitination ; Antineoplastic Agents/pharmacology*

BACKGROUND: Mutations in the structural domain of the epidermal growth factor receptor (EGFR) kinase represent a critical pathogenetic factor in non-small cell lung cancer (NSCLC). Small-molecule EGFR-tyrosine kinase inhibitors (TKIs) serve as first-line therapeutic agents for the treatment of EGFR-mutated NSCLC. But the resistance mutations of EGFR restrict the clinical application of EGFR-TKIs. In this study, we constructed a clinically relevant PC-9 EGFRD19/T790M/C797S cellular model featuring the mutation type within the EGFRD19/T790M/C797S. This model aims to investigate the inhibitory effects of small-molecule EGFR-TKIs and to provide a cellular platform for developing a new generation of innovative drugs that target resistance associated with EGFR mutations. METHODS: Clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9 (CRISPR/Cas9) technology was employed to knock in the EGFRT790M/C797S mutant fragment into NSCLC PC-9 cells, originally harboring the EGFRD19 mutation, to generate the PC-9 EGFRD19/T790M/C797S cell model. This model, with the EGFRD19/T790M/C797S mutant, was used to investigate the inhibitory effects of EGFR-TKIs on cell proliferation through MTS assay. Additionally, Western blot analysis was conducted to assess the regulation of EGFR protein expression and the phosphorylation levels of downstream signaling molecules, including protein kinase B (AKT) and mitogen-activated protein kinase (MAPK). RESULTS: PC-9 EGFRD19/T790M/C797S cells, with the EGFRD19/T790M/C797S mutation, were successfully generated using CRISPR/Cas9 technology. In terms of proliferation inhibition, the marketed first-, second-, and third-generation EGFR-TKIs that were ineffective against the EGFRD19/T790M/C797S mutation showed weak proliferation inhibitory activity against this cell line, and the proliferation inhibition (half maximal inhibitory concentration, IC50)>1000 nmol/L; in contrast, the fourth-generation EGFR-TKIs in development, which have better efficacy against the EGFRD19/T790M/C797S mutation, showed strong proliferation inhibition in this cell model. On mechanistic validation, the first-, second-, and third-generation EGFR-TKIs had weak inhibitory activity on the phosphorylation of EGFR and the downstream AKT/MAPK signaling pathway in this cell line, whereas the fourth generation of EGFR-TKIs under development significantly inhibited the phosphorylation of EGFR and the downstream AKT/MAPK signaling pathway in this cell line. CONCLUSIONS Using CRISPR/Cas9 technology, the EGFRT790M/C797S mutant fragment was successfully knocked into PC-9 cells to create cell lines harboring the EGFRD19/T790M/C797S mutation. The study demonstrated that the EGFR-TKIs showed different sensitivities to whether the EGFRD19/T790M/C797S mutation was effective or not and different inhibitory effects on the phosphorylation of EGFR and downstream pathways, which demonstrated that this cell line depended on the activation of the EGFRD19/T790M/C797S mutation and EGFR/AKT/MAPK signaling pathway for proliferation. This study provides a clinically relevant cellular evaluation and mechanism validation system for the development of a new generation of innovative drugs targeting EGFR mutation resistance.
ErbB Receptors/metabolism* ; Carcinoma, Non-Small-Cell Lung/metabolism* ; Humans ; Drug Resistance, Neoplasm/genetics* ; Lung Neoplasms/metabolism* ; Protein Kinase Inhibitors/pharmacology* ; Mutation ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Antineoplastic Agents/pharmacology*

With the rapid development of epidermal growth factor receptor (EGFR) gene testing of lung adenocarcinoma patients has been routinely carried out, EGFR mutations are also possible for some small samples of non-smoking female lung squamous cell carcinoma patients. This increases the opportunity for targeted therapy for this group of patients. However, drug resistance in patients with lung squamous cell carcinoma during targeted therapy is an important factor affecting subsequent treatment. There are multiple mechanisms of acquired drug resistance in targeted therapy, and the alteration of mesenchymal-epithelial transition factor (MET) signaling pathway is one of the common mechanisms of drug resistance. At present, some selective tyrosine kinase inhibitors (TKIs) of MET has been approved for non-small cell lung cancer with MET gene 14 exon skipping mutation, such as Glumetinib, Savolitinib, Tepotinib, Capmatinib, etc. Drugs that target secondary MET amplification are still in clinical trials. This paper retrospectively analyzed the clinical data of a female patient with EGFR-TKIs resistant secondary MET amplified squamous cell lung cancer, and reviewed relevant literature to explore how to optimize the treatment of lung squamous cell carcinoma patients with EGFR mutation, so as to provide clinical reference for the diagnosis and treatment of such patients.
.
Female ; Humans ; Carcinoma, Squamous Cell/drug therapy* ; Drug Resistance, Neoplasm/genetics* ; ErbB Receptors/antagonists & inhibitors* ; Gene Amplification ; Lung Neoplasms/drug therapy* ; Protein Kinase Inhibitors/pharmacology* ; Proto-Oncogene Proteins c-met/genetics*

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are currently the first-line standard of care for patients with non-small cell lung cancer (NSCLC) that harbor EGFR mutations. Nevertheless, resistance to EGFR-TKIs is inevitable. In recent years, although immune checkpoint inhibitors (ICIs) have significantly shifted the treatment paradigm in advanced NSCLC without driver mutation, clinical benefits of these agents are limited in patients with EGFR-mutated NSCLC. Compared with wild-type tumors, tumors with EGFR mutations show more heterogeneity in the expression level of programmed cell death ligand 1 (PD-L1), tumor mutational burden (TMB), and other tumor microenvironment (TME) characteristics. Whether ICIs are suitable for NSCLC patients with EGFR mutations is still worth exploring. In this review, we summarized the clinical data with regard to the efficacy of ICIs in patients with EGFR-mutated NSCLC and deciphered the unique TME in EGFR-mutated NSCLC.
.
Humans ; Carcinoma, Non-Small-Cell Lung/genetics* ; Lung Neoplasms/genetics* ; ErbB Receptors/metabolism* ; Immunotherapy ; Mutation ; B7-H1 Antigen/genetics* ; Protein Kinase Inhibitors/pharmacology* ; Tumor Microenvironment

The treatment of chronic myeloid leukemia (CML) was revolutionized with the advent of the first-generation tyrosine kinase inhibitors (TKIs), but drug resistance developed during treatment, leading to the development of the second-generation (dasatinib, nilotinib, and bosutinib) and third-generation (ponatinib) TKI. Compared with previous treatment regimens, specific TKI can significantly improve the response rate, overall survival rate and prognosis of CML. Only a few patients with BCR-ABL mutation are insensitive to the second-generation TKIs, so it is suggested to select the second-generation TKIs for patients with specific mutations. For patients with other mutations and without mutations, the second-generation TKI should be selected according to the patient's medical history, while the third-generation TKIs should be selected for mutations that are insensitive to the second-generation TKIs, such as T315I mutation that is sensitive to ponatinib. Due to different BCR-ABL mutations in patients with different sensitivity to the second and third-generation TKIs, this paper will review the latest research progress of the efficacy of the second and third-generation TKIs in CML patients with BCR-ABL mutations.
Humans ; Antineoplastic Agents/pharmacology* ; Dasatinib/pharmacology* ; Drug Resistance, Neoplasm/genetics* ; Fusion Proteins, bcr-abl/genetics* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Mutation ; Protein Kinase Inhibitors/therapeutic use*

Lung cancer is the most common malignancy in the world and the leading cause of cancer death. Human epidermal growth factor receptor 2 (HER2) positive non-small cell lung cancer (NSCLC) refers to the NSCLC caused by mutation, amplification or overexpression of the HER2 gene, resulting in its dysfunction. HER2 is the most active receptor in the HER family and can combine with other members to form dimers, which can activate multiple signaling pathways and regulate cell proliferation, differentiation, migration and apoptosis. In NSCLC, HER2 positivity is usually considered a poor prognostic marker. At present, the diagnosis and treatment of HER2-positive NSCLC are not mature. Immunohistochemistry (IHC), next generation sequencing (NGS) and other technologies are often used to detect the positive status of HER2 mutation, amplification or overexpression. In previous studies, antitumor drugs did not show ideal therapeutic effects in HER2-positive NSCLC. However, in recent years, related researches have shown that antibody-drug conjugates (ADCs) and new tyrosine kinase inhibitors (TKIs) in targeted therapy show good antitumor activity against HER2 positive NSCLC. This article summarized the progress in diagnosis and treatment of HER2-positive NSCLC, so as to provide reference for subsequent researches.
.
Humans ; Carcinoma, Non-Small-Cell Lung/genetics* ; Lung Neoplasms/genetics* ; Receptor, ErbB-2/genetics* ; Mutation ; Antineoplastic Agents/pharmacology* ; Signal Transduction ; Protein Kinase Inhibitors/therapeutic use*

Lung cancer is the most common in incidence and mortality worldwide. With the development of next generation sequencing (NGS) detection technology, more and more patients with rare anaplastic lymphoma kinase (ALK) fusion mutations were detected. A case of advanced lung adenocarcinoma with rare COX7A2L-ALK (C2:A20) fusion detected by NGS was reported in Peking Union Medical College Hospital, and all cases with rare ALK fusion mutations were searched from medical datebase from January 1, 2014 to March 31, 2021, to investigate the treatment of rare ALK fusion mutations with ALK inhibitors. The best response of the patient was assessed as partial response (PR) with Ceritinib treatment. By literature review, 22 cases of rare ALK fusion were reported in 19 articles. Combined with this case, 23 cases were analyzed. The objective response rate (ORR) was 82.6% (19/23) and disease control rate (DCR) was 95.7% (22/23) for rare ALK fusions patients treated with ALK inhibitors. Lung adenocarcinoma patients with rare ALK fusion could benefit from ALK inhibitors.
.
Humans ; Anaplastic Lymphoma Kinase/genetics* ; Lung Neoplasms/diagnosis* ; Crizotinib ; Adenocarcinoma of Lung/genetics* ; Protein Kinase Inhibitors/pharmacology* ; Oncogene Proteins, Fusion/genetics*