Clinical experiences with molecular targeted therapy in lung cancer in China

Decoding dynamic interactions between EGFR-TKD and DAC through computational and experimental approaches: A novel breakthrough in lung melanoma treatment

In the quest for effective lung cancer treatments, the potential of 3,6-diaminoacridine-9-carbonitrile (DAC) has emerged as a game changer. While DAC's efficacy against glioblastoma is well documented, its role in combating lung cancer has remained largely untapped. This study focuses on CTX-1, exploring its interaction with the pivotal EGFR-TKD protein, a crucial target in lung cancer therapeutics. A meticulous molecular docking analysis revealed that CTX-1 exhibits a noteworthy binding affinity of -7.9 kcal/mol, challenging Erlotinib, a conventional lung cancer medication, which displayed a binding affinity of -7.3 kcal/mol. For a deeper understanding of CTX-1's molecular mechanics, this study employed rigorous 100-ns molecular dynamics simulations, demonstrating CTX-1's remarkable stability in comparison with erlotinib. The Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) method further corroborated these results, with CTX-1 showing a free binding energy of -105.976 ± 1.916 kJ/mol. The true prowess of CTX-1 was tested against diverse lung cancer cell lines, including A549, Hop-62 and H-1299. CTX-1 not only significantly outperformed erlotinib in anticancer activity but also exhibited a spectrum of therapeutic effects. It effectively diminished cancer cell viability, induced DNA damage, halted cell cycle progression, generated reactive oxygen species (ROS), impaired mitochondrial transmembrane potential, instigated apoptosis and successfully inhibited EGFR-TKD. This study not only underscores the potential of CTX-1 a formidable contender in lung cancer treatment but also marks a paradigm shift in oncological therapeutics, offering new horizons in the fight against this formidable disease.

Application status and future prospects of the PDX model in lung cancer

Lung cancer is one of the most prevalent, fatal, and highly heterogeneous diseases that, seriously threaten human health. Lung cancer is primarily caused by the aberrant expression of multiple genes in the cells. Lung cancer treatment options include surgery, radiation, chemotherapy, targeted therapy, and immunotherapy. In recent decades, significant progress has been made in developing therapeutic agents for lung cancer as well as a biomarker for its early diagnosis. Nonetheless, the alternative applications of traditional pre-clinical models (cell line models) for diagnosis and prognosis prediction are constrained by several factors, including the lack of microenvironment components necessary to affect cancer biology and drug response, and the differences between laboratory and clinical results. The leading reason is that substantial shifts accrued to cell biological behaviors, such as cell proliferative, metastatic, invasive, and gene expression capabilities of different cancer cells after decades of growing indefinitely in vitro. Moreover, the introduction of individualized treatment has prompted the development of appropriate experimental models. In recent years, preclinical research on lung cancer has primarily relied on the patient-derived tumor xenograft (PDX) model. The PDX provides stable models with recapitulate characteristics of the parental tumor such as the histopathology and genetic blueprint. Additionally, PDXs offer valuable models for efficacy screening of new cancer drugs, thus, advancing the understanding of tumor biology. Concurrently, with the heightened interest in the PDX models, potential shortcomings have gradually emerged. This review summarizes the significant advantages of PDXs over the previous models, their benefits, potential future uses and interrogating open issues.

Roles of Krüppel-like factor 6 splice variant 1 in the development, diagnosis, and possible treatment strategies for non-small cell lung cancer

Krüppel-like factor 6 (KLF6) is a nuclear transcriptional regulator found in mammalian tissue that has been identified as a tumor suppressor gene in several malignancies. As a result of loss of heterozygosity, DNA methylation, and alternative splicing, it is frequently inactivated in various malignancies. Krüppel-like factor 6 splice variant 1 (KLF6-SV1), Krüppel-like factor 6 splice variant 2, and Krüppel-like factor 6 splice variant 3 alternatively spliced isoforms that emerge from a single nucleotide polymorphism in the KLF6 gene. KLF6-SV1 is generally upregulated in multiple cancers, and its biological function is well understood. Overexpression of KLF6-SV1 inhibits the KLF6 gene function while promoting tumor progression, which is associated with a poor prognosis in patients with various malignancies. We reviewed the progress of KLF6-SV1 research in NSCLC over the last several years to understand the molecular mechanisms of tumorigenesis, tumor development, and therapy resistance. Finally, this review emphasizes the therapeutic potential of small interfering RNA targeted silencing of KLF6-SV1 as a novel strategy for managing chemotherapy resistance in NSCLC patients.

The KLF6 splice variant KLF6-SV1 promotes proliferation and invasion of non-small cell lung cancer by up-regultating PI3K-AKT signaling pathway

Non-small cell lung cancer (NSCLC) is an aggressive type of lung malignancy. Most of the patients have poor prognosis. Increasing evidence has revealed an association between KLF6-SV1, known as an oncogenic splice variant of KLF6, and metastatic potential or poor prognosis in many cancers. We previously demonstrated the increased KLF6-SV1 expression in NSCLC samples. There was a significant association between increased expression of KLF6-SV1 with the pN and pTNM stages and poor survival in NSCLC patients. In the present study, we aimed to further investigate the functional role of KLF6-SV1 in the progression of NSCLC. SK-MES-1 cells were infected with Lenti-virus containing KLF6-SV1 to up-regulate its expression, and the small interfering RNA (siRNA) was designed to knock down KLF6-SV1 transcript level in A549 cells. CCK8, colony formation, wound-healing, and transwell assays were performed to examine cell proliferation, migration, and invasion respectively. Western blot assay was used to detect the expression or phosphorylation of related proteins. We found that in vitro silencing of KLF6-SV1 by siRNA inhibited A549 cell proliferation, migration, and invasion through changes in E-cadherin, N-cadherin, Vimentin, Snail1 and Snail2 expression. Furthermore, KLF6-SV1 isoform knockdown triggered caspase-dependent apoptosis of A549 cells through downregulation of the phosphatidylinositol 3-OH kinase (PI3K)/Akt signaling pathway and apoptosis-related protein expression. Overexpression of KLF6-SV1 transcript induced significant increase in proliferation, migration, invasion and changes in expression of related proteins. Our study support KLF6-SV1 might be an important player in modulating the growth, migration, invasion, and survival of NSCLC cells, and that silencing KLF6-SV1 siRNA has the potential to be a powerful gene therapy strategy for NSCLC.

Establishment of lung cancer patient-derived xenograft models and primary cell lines for lung cancer study

Background

The overall 5-year survival rate of lung cancer is about 15% even with therapeutic drugs like tyrosine kinase inhibitors. Ideal models are urgently needed for exploring mechanisms and finding new drugs. Patient-derived xenografts (PDX) models and primary cells are both used to screen therapeutic regimens for cancer. However, PDX models and primary cells from the same patient are difficult to establish. Their consistency to the original tumor tissue is not well studied.

Methods

31 lung cancer patient tissues were procured to establish the lung cancer PDX models and primary cell lines. Tumor growth measurements, histological and immunohistochemistry analysis, Western blotting, EGFR and K-RAS mutation detection and gefitinib sensitive assay were performed to evaluate the characteristic of established PDX models. Immunofluorescence analysis, anchorage-independent cell growth, Western blotting and gefitinib sensitive assay were performed to assay the characteristic of established primary cell lines. The whole-exome sequencing was used to compare the characteristic of the patient’s tumor tissue, established PDX and primary cell line.

Results

Twenty-one lung cancer PDX models (67.74%, 21/31) and ten primary cell lines (32.25%, 10/31) were established from patients’ tumor tissues. The histology and pathological immunohistochemistry of PDX xenografts are consistent with the patients’ tumor samples. Various signal pathways were activated in different PDX models (n = 5) and primary cell lines (n = 2). EGFR mutation PDX model and primary cell line (LG1) were sensitive to gefitinib treatment. The expression of CK8/18, TTF1 and NapsinA in LG1 and LG50 primary cells were also positive. And the activated signal pathways were activated in LG1 and LG50 primary cell lines. Furthermore, the gene mutation in PDX tumor tissues and primary cell line (LG50) was consistent with the mutation in LG50 patient’s tumor tissues.

Conclusion

These data suggested that established lung cancer PDX models and primary cell lines reserved mostly molecular characteristics of primary lung cancer and could provide a new tool to further understand the mechanisms and explore new therapeutic strategies.

The action and mechanism of myrislignan on A549 cells in vitro and in vivo

Myrislignan is a natural compound with little pharmacological study. In our investigation, we investigated the effect of myrislignan in the induction of apoptosis in A549 cells in vitro and in vivo. Myrislignan inhibited the proliferation of A549 cells in a dose- and time-dependent manner assayed by MTT. In addition, Hoechst flow cytometry showed that myrislignan significantly induced apoptosis and cell cycle arrest in A549 cells. The apoptosis and anti-cell proliferation was mediated by the activation of mitogen-activated protein kinase and the inhibition of epidermal growth factor receptor signal pathway, change of mitochondrial membrane potential, the releasing of c-Myc, the downregulation of the level of the anti-apoptotic protein Bcl-2, and the upregulation of the level of the pro-apoptotic protein Bax. In conclusion, those results reveal a potential mechanism for the anti-cancer effect of myrislignan on human lung cancer, while suggesting that myrislignan may be a promising compound for the treatment of lung cancer.

Development of epidermal growth factor receptor tyrosine kinase inhibitors against EGFR T790M. Mutation in non small-cell lung carcinoma

Individualized therapies targeting epidermal growth factor receptor (EGFR) mutations show promises for the treatment of non small-cell lung carcinoma (NSCLC). However, disease progression almost invariably occurs 1 year after tyrosine kinase inhibitor (TKI) treatment. The most prominent mechanism of acquired resistance involves the secondary EGFR mutation, namely EGFR T790M, which accounts for 50%-60% of resistant tumors. A large amount of studies have focused on the development of effective strategies to treat TKI-resistant EGFR T790M mutation in lung tumors. Novel generations of EGFR inhibitors are producing encouraging results in patients with acquired resistance against EGFR T790M mutation. This review will summarize the novel inhibitors, which might overcome resistance against EGFR T790M mutation.