Detection of multiple druggable mutations of lung cancer from cytology specimens by MINtS: An advanced medicine A trial.

Most multigene mutation tests require tissue specimens. However, cytological specimens are easily obtained in the clinical practice and provide high-quality DNA and RNA. We aimed to establish a test that utilizes cytological specimens and performed a multi-institutional study to investigate the performance of MINtS, a test based on next-generation sequencing. A standard procedure for specimen isolation was defined. The specimens were considered suitable for the test if >100 ng DNA and >50 ng RNA could be extracted from them. In total, 500 specimens from 19 institutions were investigated. MINtS detected druggable mutations in 63% (136 of 222) of adenocarcinomas. Discordant results between MINtS and the companion diagnostics were observed in 14 of 310 specimens for the EGFR gene, and 6 of 339 specimens for the ALK fusion genes. Confirmation by other companion diagnostics for the EGFR mutations or the clinical response to an ALK inhibitor all supported the results obtained by MINtS. MINtS along with the isolation procedure presented in the current study will be a platform to establish multigene mutation tests that utilize cytological specimens. UMIN000040415.

Integrin alpha 2 is associated with tumor progression and postoperative recurrence in non-small cell lung cancer.

BACKGROUND: Integrins are transmembrane proteins that mediate cell adhesion to extracellular matrix. Whereas expression of integrin alpha 2 is associated with motility, invasiveness and cellular differentiation in various tumors, the role of integrin alpha 2 in lung cancer has not been studied in detail. The aim of this study was to determine whether and how aberrant integrin alpha 2 expression in non-small cell lung cancer leads to different outcomes. METHODS: We measured expression of integrin alpha 2 by quantitative polymerase chain reaction in 100 samples collected from non-small cell lung cancer patients who had undergone surgical resection. We assigned patients to high and low expression groups and analyzed survival. Cellular morphology, adhesion, proliferation, migration and invasion were examined in human lung cancer cell lines. RESULTS: Among 100 cases, 41 were female, with a median age of 71 years. High expression of integrin alpha 2 in non-small cell lung cancer was associated with lower recurrence-free survival (P = 0.004). Overexpression of integrin alpha 2 in cell lines had no effect on cell proliferation or invasion but resulted in increased cell size (1416 µm2 versus 470 µm2 in H522 cells, P < 0.001; 1822 µm2 versus 1029 µm2 in H661 cells, P = 0.02), adhesion (P < 0.001 in H522 and H661 cells) and migration (gap area filled was 71% versus 36% in H522 cells, P < 0.001; 57% versus 26% in H661 cells, P = 0.001). These changes were suppressed by E7820, an inhibitor of integrin alpha 2. CONCLUSIONS: Integrin alpha 2 may play a significant role in lung cancer adhesion and migration, and may lead to a higher risk of recurrence.

FGF23-related hypophosphatemia in a patient with small cell lung cancer: a case report and literature review.

Although there are a few case reports of patients with small cell lung cancer developing hypophosphatemia, detailed information on this condition is scarce. A 52-year-old patient with advanced stage small cell lung cancer developed hypophosphatemia (1.1 mg/dL) during chemotherapy. A reduced level of the tubular reabsorption of phosphate concomitant with an inappropriately elevated level of fibroblast growth factor (FGF) 23 (48.4 pg/mL) was noted, leading to the diagnosis of FGF23-related hypophosphatemia. Laboratory data also showed hypercortisolemia with an elevated ACTH level and hyponatremia with an inappropriately unsuppressed level of antidiuretic hormone (ADH). These data suggested the overproduction of FGF23 in addition to ACTH and ADH. Because the octreotide loading test did not present a suppressive effect on ACTH or FGF23 levels, the patient was treated with phosphate supplementation, active vitamin D and metyrapone, which partially improved the serum phosphate and cortisol levels. Even after two subsequent courses of chemotherapy, the small cell lung cancer progressed, and the FGF23 level was further elevated (83.7 pg/mL). Although it is very rare, FGF23-related hypophosphatemia is one of the hormonal disturbances that could be observed in patients with small cell lung cancer. This article reviews similar clinical conditions and revealed that advanced states of malignancy seemed to be associated with the development of renal wasting hypophosphatemia, especially in lung cancer and prostate cancer. Therefore, the parameters related to hypophosphatemia should be monitored in patients with advanced small cell lung cancer to prevent the development of hypophosphatemic osteomalacia.

New Cell Cycle Inhibitors Target Aneuploidy in Cancer Therapy.

Aneuploidy is a hallmark of cancer. Defects in chromosome segregation result in aneuploidy. Multiple pathways are engaged in this process, including errors in kinetochore-microtubule attachments, supernumerary centrosomes, spindle assembly checkpoint (SAC) defects, and chromosome cohesion defects. Although aneuploidy provides an adaptation and proliferative advantage in affected cells, excessive aneuploidy beyond a critical level can be lethal to cancer cells. Given this, enhanced chromosome missegregation is hypothesized to limit survival of aneuploid cancer cells, especially when compared to diploid cells. Based on this concept, proteins and pathways engaged in chromosome segregation are being exploited as candidate therapeutic targets for aneuploid cancers. Agents that induce chromosome missegregation and aneuploidy now exist, including SAC inhibitors, those that alter centrosome fidelity and others that are under active study in preclinical and clinical contexts. This review explores the therapeutic potentials of such new agents, including the benefits of combining them with other antineoplastic agents.

Polo-like kinase 4 inhibition produces polyploidy and apoptotic death of lung cancers.

Polo-like kinase 4 (PLK4) is a serine/threonine kinase regulating centriole duplication. CFI-400945 is a highly selective PLK4 inhibitor that deregulates centriole duplication, causing mitotic defects and death of aneuploid cancers. Prior work was substantially extended by showing CFI-400945 causes polyploidy, growth inhibition, and apoptotic death of murine and human lung cancer cells, despite expression of mutated KRAS or p53. Analysis of DNA content by propidium iodide (PI) staining revealed cells with >4N DNA content (polyploidy) markedly increased after CFI-400945 treatment. Centrosome numbers and mitotic spindles were scored. CFI-400945 treatment produced supernumerary centrosomes and mitotic defects in lung cancer cells. In vivo antineoplastic activity of CFI-400945 was established in mice with syngeneic lung cancer xenografts. Lung tumor growth was significantly inhibited at well-tolerated dosages. Phosphohistone H3 staining of resected lung cancers following CFI-400945 treatment confirmed the presence of aberrant mitosis. PLK4 expression profiles in human lung cancers were explored using The Cancer Genome Atlas (TCGA) and RNA in situ hybridization (RNA ISH) of microarrays containing normal and malignant lung tissues. PLK4 expression was significantly higher in the malignant versus normal lung and conferred an unfavorable survival (P < 0.05). Intriguingly, cyclin dependent kinase 2 (CDK2) antagonism cooperated with PLK4 inhibition. Taken together, PLK4 inhibition alone or as part of a combination regimen is a promising way to combat lung cancer.

TRIGGERING ANAPHASE CATASTROPHE TO COMBAT ANEUPLOID CANCERS.

Cancer cells are genetically unstable and often have supernumerary centrosomes. When supernumerary centrosome clustering is inhibited at mitosis, multipolar cell division is forced, triggering apoptosis in daughter cells. This proapoptotic pathway is called anaphase catastrophe. Cyclin-dependent kinase 1 (CDK1) or CDK2 inhibitors can antagonize centrosome clustering and cause anaphase catastrophe to occur in lung cancer and other types of cancer. The centrosome protein CP110, a CDK1 and CDK2 phosphorylation substrate, engages anaphase catastrophe. Intriguingly, CP110 is downregulated by the KRAS oncoprotein, enhancing sensitivity of KRAS-driven cancers to CDK2 inhibitors. Anaphase catastrophe eradicates aneuploid cancer cells while relatively sparing normal diploid cells with two centrosomes. This therapeutic window discriminates between normal and neoplastic cells and can be exploited in the cancer clinic. The work reviewed here establishes that pharmacologically-induced anaphase catastrophe is useful to combat aneuploid cancers, especially when the KRAS oncoprotein is activated. This addresses an unmet medical need in oncology.

The chimeric transcript RUNX1-GLRX5: a biomarker for good postoperative prognosis in Stage IA non-small-cell lung cancer.

Stage IA non-small-cell lung cancer cases have been recognized as having a low risk of relapse; however, occasionally, relapse may occur. To predict clinical outcome in Stage IA non-small-cell lung cancer patients, we searched for chimeric transcripts that can be used as biomarkers and identified a novel chimeric transcript, RUNX1-GLRX5, comprising RUNX1, a transcription factor, and GLRX5. This chimera was detected in approximately half of the investigated Stage IA non-small-cell lung cancer patients (44/104 cases, 42.3%). Although there was no significant difference in the overall survival rate between RUNX1-GLRX5-positive and -negative cases (P = 0.088), a significantly lower relapse rate was observed in the RUNX1-GLRX5-positive cases (P = 0.039), indicating that this chimera can be used as a biomarker for good prognosis in Stage IA patients. Detection of the RUNX1-GLRX5 chimeric transcript may therefore be useful for the determination of a postoperative treatment plan for Stage IA non-small-cell lung cancer patients.

["Anger" Seen in Obsessive-compulsive Disorder : A Study of 40 Subjects Who Underwent Inpatient Morita Therapy].

We conducted a study on "anger" seen in obsessive-compulsive disorder (OCD). Subjects were 40 men and women (age range: 20-58 years) admitted to the Jikei University Center for Morita Therapy who had been diagnosed with OCD (DSM-IV-TR) and undergone inpatient Morita therapy. The Japanese version of the Structured Clinical Interview for DSM-IV (SCID) (DSM-IV Axis I and Axis II diagnoses), the Yale-Brown Obsessive Compulsive Scale (Y- BOCS) (changes in OCD severity), the State-Trait Anger Expression Inventory (STAXI-2) using "anger" as the indicator, and the State-Trait Anxiety Inventory (STAI) using "anxiety" as the indicator were used, and the data were subjected to statistical analysis. Improvements were seen in the Y-BOCS for all of the following : total score, obsessional idea, compulsive act, insight, and avoidance. These results indicate that inpatient Morita ther- apy improves OCD. In the STAI, improvements were seen for both state anxiety and trait anxiety. Improvement of trait anxiety may be considered an indicator of the cultivation of a hypochondriacal temperament. In the STAXI-2, improvements were seen for anger reaction and anger expression-in, which are both aspects of the obsessive-compulsive style (Salzman, L.). Improvements in these items therefore indicate that inpatient Morita therapy improves aspects of the obsessive-compulsive style. A correlation with the degree of OCD improvement was observed for the insight level. Poor insight was a factor associated with poor outcomes of inpatient Morita therapy. Furthermore, two cases were presented, and the actual condition of treatment for OCD and "anger" in inpatient Morita therapy was elucidated.

Mice null for the deubiquitinase USP18 spontaneously develop leiomyosarcomas.

BACKGROUND: USP18 (ubiquitin-specific protease 18) removes ubiquitin-like modifier interferon stimulated gene 15 (ISG15) from conjugated proteins. USP18 null mice in a FVB/N background develop tumors as early as 2 months of age. These tumors are leiomyosarcomas and thus represent a new murine model for this disease. METHODS: Heterozygous USP18 +/- FVB/N mice were bred to generate wild-type, heterozygous and homozygous cohorts. Tumors were characterized immunohistochemically and two cell lines were derived from independent tumors. Cell lines were karyotyped and their responses to restoration of USP18 activity assessed. Drug testing and tumorigenic assays were also performed. USP18 immunohistochemical staining in a large series of human leiomyosacomas was examined. RESULTS: USP18 -/- FVB/N mice spontaneously develop tumors predominantly on the back of the neck with most tumors evident between 6-12 months (80 % penetrance). Immunohistochemical characterization of the tumors confirmed they were leiomyosarcomas, which originate from smooth muscle. Restoration of USP18 activity in sarcoma-derived cell lines did not reduce anchorage dependent or independent growth or xenograft tumor formation demonstrating that these cells no longer require USP18 suppression for tumorigenesis. Karyotyping revealed that both tumor-derived cell lines were aneuploid with extra copies of chromosomes 3 and 15. Chromosome 15 contains the Myc locus and MYC is also amplified in human leiomyosarcomas. MYC protein levels were elevated in both murine leiomyosarcoma cell lines. Stabilized P53 protein was detected in a subset of these murine tumors, another feature of human leiomyosarcomas. Immunohistochemical analyses of USP18 in human leiomyosarcomas revealed a range of staining intensities with the highest USP18 expression in normal vascular smooth muscle. USP18 tissue array analysis of primary leiomyosarcomas from 89 patients with a clinical database revealed cases with reduced USP18 levels had a significantly decreased time to metastasis (P = 0.0441). CONCLUSIONS: USP18 null mice develop leiomyosarcoma recapitulating key features of clinical leiomyosarcomas and patients with reduced-USP18 tumor levels have an unfavorable outcome. USP18 null mice and the derived cell lines represent clinically-relevant models of leiomyosarcoma and can provide insights into both leiomyosarcoma biology and therapy.

[A Case with the Increased PT-INR after the Addition of Mirtazapine to Warfarin Therapy].

OBJECTIVE: To report a case of warfarinization involving a patient who developed nasal bleeding and an elevated prothrombin time-international normalized ratio (PT-INR) after taking 15 mg of mirtazapine. CASE SUMMARY: A 70-year-old Japanese man with anxiety and irritation was admitted to the ER of our hospital with nasal bleeding. His medical history included atrial fibrillation, treated with warfarin at 3.0 mg a day, hypertension, and diabetus mellitus. He had also been taking mirtazapine at 15 mg. He experienced nasal bleeding 4 days after the initiation of therapy with mirtazapine. His PT-INR markedly elevated from 1.21 before therapy to 7.93 after therapy. Both mirtazapine and warfarin were immediately discontinued by his cardiologist. One week later, PT-INR had normalized (1.00) and the nasal bleeding had resolved. DISCUSSION: The metabolism of warfarin involves several cytochrome P450 isoenzymes, including CYP1A2, CYP2C9, CYP2C19, and CYP3A4. Mirtazapine is metabolized primarily by CYP2D6 and CYP3A4, with lesser contributions by CYP1A2. A competitive enzyme inhibition may occur, with CYP3A4 metabolizing the two drugs. No drug interaction was seen with his other medications. CONCLUSION: The coadministration of mirtazapine and warfarin can result in an increase in the anticoagulant effect of warfarin. This case shows the need to closely monitor potential drug interactions in the elderly, especially those taking mirtazapine and warfarin.

Diagnostic yield of flexible bronchoscopy for immunocompromised patients with lung infiltrates: A single-center, retrospective study.

BACKGROUND: Pulmonary complications are associated with mortality in immunocompromised patients. The usefulness of bronchoscopy has been reported. However, clinical factors and procedures that influence diagnostic yield are still not established. MATERIALS AND METHODS: We retrospectively analyzed 115 bronchoscopies performed on 108 immunocompromised patients, defined as those who take corticosteroids and/or immunosuppressants. We evaluated clinical factors, sampling procedures, final diagnosis, and severe complications of bronchoscopy. RESULTS: The clinical diagnosis was obtained in 51 patients (44%). Of those, 33 cases were diagnosed as infectious diseases and 18 as non-infectious diseases. Nine out of 115 cases (7.8%) initiated new immunosuppressive treatment for an underlying disorder based on the negative microbiological results obtained with bronchoscopy. Collagen vascular disease was the most common underlying disorders (62 patients, 54%). Bronchoscopy was useful regardless of whether the patient was immunosuppressed to treat collagen vascular disease (P = 0.47). Performing transbronchial biopsy correlated with better diagnostic yield of bronchoscopy (54.7% vs 35.5%, P = 0.049). Other clinical factors, such as radiological findings, respiratory failure or antibiotic use at the time of bronchoscopy did not significantly influence diagnostic yield. Respiratory failure requiring intubation after bronchoscopy occurred only in one case (0.9%). CONCLUSIONS: Our study implied the transbronchial biopsy may be a useful procedure for reaching a diagnosis in immunocompromised patients with pulmonary infiltrates. In addition, our data suggest the usefulness of bronchoscopy for immunocompromised patients due to the treatment of collagen vascular disease as well as other underlying disorders.

NECTIN2 is a prognostic biomarker and potential therapeutic target in lung adenocarcinoma.

INTRODUCTION: NECTINs are transmembrane proteins mediating cell-to-cell adhesion. NECTINs interact with integrins or other membrane receptors to trigger multiple cellular functions. Aberrant NECTIN expression is associated with cancer progression and poor outcomes. While NECTIN2 is overexpressed in various cancer types, its role in lung cancer is not well understood. MATERIAL AND METHODS: We investigated the function of NECTIN2 in lung adenocarcinoma (LUAD) using the Cancer Genome Atlas (TCGA) dataset and clinical samples of 105 LUAD patients who had undergone surgical resection. Cell proliferation, apoptosis, migration and invasion were investigated using human lung adenocarcinoma cell lines. RESULTS: We found that high NECTIN2 expression correlated with reduced overall survival in LUAD in TCGA database. In clinical samples, high NECTIN2 expression was associated with lower recurrence-free survival in all patients (P < 0.001) and in stage I patients (P = 0.001). Functional analyses demonstrated that NECTIN2 knockout promoted cell apoptosis and diminished cell proliferation and migration capacity. NECTIN2 overexpression did not significantly affect cellular functions. DISCUSSION: Our results suggest that NECTIN2 plays a significant role in cell apoptosis and cancer cell migration, leading to increased postoperative recurrence. Furthermore, NECTIN2 serves as a prognostic indicator and a potential therapeutic target in LUAD. CONCLUSIONS: High NECTIN2 expression in LUAD was found to be associated with postoperative recurrence, and was observed to play an important role in cell apoptosis and migration.

Detection of novel paraja ring finger 2-fer tyrosine kinase mRNA chimeras is associated with poor postoperative prognosis in non-small cell lung cancer.

Previously, we reported that the overexpression of fer tyrosine kinase (FER), a non-receptor tyrosine kinase, is correlated with poor postoperative prognosis and cancer-cell survival in non-small cell lung cancer (NSCLC). In the present study, we further analyzed FER-overexpressed NSCLC cases and identified various patterns of chimeric mRNAs, composed of paraja ring finger 2 (PJA2) and FER. We detected no genomic rearrangements between PJA2 and FER and attributed these chimeric mRNAs to alterations at the transcriptome level: i.e., trans-splicing. Several chimeric patterns were detected concurrently in each patient, and the pattern sets varied among patients, although the pattern in which PJA2 exon 1 was fused to FER exon 3 (designated as Pe1-Fe3 mRNA) was detected constantly. Therefore, in a wide screening for PJA2-FER mRNAs in NSCLC, we focused on this chimeric pattern as a representative chimera. In analyses of 167 NSCLC samples, Pe1-Fe3 mRNA was identified in about 10% of the patients, and the presence of chimeric mRNA was significantly correlated with a high expression level of parental FER mRNA. Furthermore, we found that the detection of Pe1-Fe3 mRNA was correlated with poor postoperative survival periods in NSCLC, consistent with a previous finding in which FER overexpression was correlated with poor postoperative prognosis in NSCLC. This report is the first to suggest a correlation between chimeric mRNA and the expression level of parental mRNA. Furthermore, our findings may be clinically beneficial, suggesting that PJA2-FER mRNAs might serve as a novel prognostic biomarker in NSCLC.

Lung Adenocarcinoma Size Decrease after SARS-CoV-2 Vaccination during Long-Term Pembrolizumab Treatment: A Case Report.

A man in his late 40s was diagnosed with clinical stage 4B lung adenocarcinoma with a PD-L1 tumor proportion score of 100% and high tumor mutational burden. A partial response was achieved after administration of pembrolizumab. The patient received two doses of a SARS-CoV-2 vaccine (BNT162b2) after 59 courses, and a chest computed tomography revealed consolidation in the peri-tumoral area, which subsequently disappeared, and the tumor continued to shrink in the next 4 months. This case provides indirect evidence for the persistence of cancer immunity during long-term treatment with immune checkpoint inhibitors and the potential for further activation.

Pulmonary carcinoid tumour with remarkably high levels of pro-gastrin-releasing peptide: A case report.

An 86-year-old woman presented with chronic cough and chest pain. Computed tomography revealed two masses in the right lower lobe of the lung accompanied by multiple lymphadenopathies and metastasis to the rib. The pro-gastrin-releasing peptide (ProGRP) levels were notably elevated (888 pg/mL). Based on these findings, our initial clinical diagnosis was small-cell lung cancer. However, the pathological diagnosis turned out to be an atypical carcinoid. The patient was finally treated with everolimus. Clinicians should be aware that carcinoid tumours are sometimes difficult to distinguish from small-cell lung cancer with respect to high ProGRP levels and multiple metastases.

CDK2 inhibition disorders centrosome stoichiometry and alters cellular outcomes in aneuploid cancer cells.

Cyclin-dependent Kinase 2 (CDK2) inhibition prevents supernumerary centrosome clustering. This causes multipolarity, anaphase catastrophe and apoptotic death of aneuploid cancers. This study elucidated how CDK2 antagonism affected centrosome stoichiometry. Focused ion beam scanning electron microscopy (FIB-SEM) and immunofluorescent imaging were used. Studies interrogated multipolar mitosis after pharmacologic or genetic repression of CDK2. CDK2/9 antagonism with CYC065 (Fadraciclib)-treatment disordered centrosome stoichiometry in aneuploid cancer cells, preventing centrosome clustering. This caused ring-like chromosomes or multipolar cancer cells to form before onset of cell death. Intriguingly, CDK2 inhibition caused a statistically significant increase in single centrioles rather than intact centrosomes with two centrioles in cancer cells having chromosome rings or multipolarity. Statistically significant alterations in centrosome stoichiometry were undetected in other mitotic cancer cells. To confirm this pharmacodynamic effect, CDK2 but not CDK9 siRNA-mediated knockdown augmented cancer cells with chromosome ring or multipolarity formation. Notably, engineered gain of CDK2, but not CDK9 expression, reversed emergence of cancer cells with chromosome rings or multipolarity, despite CYC065-treatment. In marked contrast, CDK2 inhibition of primary human alveolar epithelial cells did not confer statistically significant increases of cells with ring-like chromosomes or multipolarity. Hence, CDK2 antagonism caused differential effects in malignant versus normal alveolar epithelial cells. Translational relevance was confirmed by CYC065-treatment of syngeneic lung cancers in mice. Mitotic figures in tumors exhibited chromosome rings or multipolarity. Thus, CDK2 inhibition preferentially disorders centrosome stoichiometry in cancer cells. Engaging this disruption is a strategy to explore against aneuploid cancers in future clinical trials.

A novel retinoic acid receptor-γ agonist antagonizes immune checkpoint resistance in lung cancers by altering the tumor immune microenvironment.

All-trans-retinoic acid (ATRA), the retinoic acid receptors (RARs) agonist, regulates cell growth, differentiation, immunity, and survival. We report that ATRA-treatment repressed cancer growth in syngeneic immunocompetent, but not immunodeficient mice. The tumor microenvironment was implicated: CD8+ T cell depletion antagonized ATRA's anti-tumorigenic effects in syngeneic mice. ATRA-treatment with checkpoint blockade did not cooperatively inhibit murine lung cancer growth. To augment ATRA's anti-tumorigenicity without promoting its pro-tumorigenic potential, an RARγ agonist (IRX4647) was used since it regulates T cell biology. Treating with IRX4647 in combination with an immune checkpoint (anti-PD-L1) inhibitor resulted in a statistically significant suppression of syngeneic 344SQ lung cancers in mice-a model known for its resistance to checkpoints and characterized by low basal T cell and PD-L1 expression. This combined treatment notably elevated CD4+ T-cell presence within the tumor microenvironment and increased IL-5 and IL-13 tumor levels, while simultaneously decreasing CD38 in the tumor stroma. IL-5 and/or IL-13 treatments increased CD4+ more than CD8+ T-cells in mice. IRX4647-treatment did not appreciably affect in vitro lung cancer growth, despite RARγ expression. Pharmacokinetic analysis found IRX4647 plasma half-life was 6 h in mice. Yet, RARα antagonist (IRX6696)-treatment with anti-PD-L1 did not repress syngeneic lung cancer growth. Together, these findings provide a rationale for a clinical trial investigating an RARγ agonist to augment check point blockade response in cancers.

Genome structure-based screening identified epigenetically silenced microRNA associated with invasiveness in non-small-cell lung cancer.

MicroRNA (miRNA) expression is frequently altered in human cancers. To search for epigenetically silenced miRNAs in non-small-cell lung cancer (NSCLC), we mapped human miRNAs on autosomal chromosomes and selected 55 miRNAs in silico. We treated six NSCLC cell lines with the DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) and determined the expressions of the 55 miRNAs. Fourteen miRNAs were decreased in the cancer cell lines and were induced after 5-aza-CdR treatment. After a detailed DNA methylation analysis, we found that mir-34b and mir-126 were silenced by DNA methylation. Mir-34b was silenced by the DNA methylation of its own promoter, whereas mir-126 was silenced by the DNA methylation of its host gene, EGFL7. A chromatin immunoprecipitation assay revealed H3K9me2 and H3K9me3 in mir-34b and EGFL7, and H3K27me3 in EGFL7. The overexpression of mir-34b and mir-126 decreased the expression of c-Met and Crk, respectively. The 5-aza-CdR treatment of lung cancer cell line resulted in increased mir-34b expression and decreased c-Met protein. We next analyzed the DNA methylation status of these miRNAs using 99 primary NSCLCs. Mir-34b and mir-126 were methylated in 41 and 7% of all the cases, respectively. The DNA methylation of mir-34b was not associated with c-Met expression determined by immunohistochemistry, but both mir-34b methylation (p = 0.007) and c-Met expression (p = 0.005) were significantly associated with lymphatic invasion in a multivariate analysis. The DNA methylation of mir-34b can be used as a biomarker for an invasive phenotype of lung cancer.

Choosing the optimal immunotherapeutic strategies for non-small cell lung cancer based on clinical factors.

The treatment landscape of advanced non-small cell lung cancer (NSCLC) has changed dramatically since the emergence of immune checkpoint inhibitors (ICIs). Although some patients achieve long survival with relatively mild toxicities, not all patients experience such benefits from ICI treatment. There are several ways to use ICIs in NSCLC patients, including monotherapy, combination immunotherapy, and combination chemoimmunotherapy. Decision-making in the selection of an ICI treatment regimen for NSCLC is complicated partly because of the absence of head-to-head prospective comparisons. Programmed death-ligand 1 (PD-L1) expression is currently considered a standard biomarker for predicting the efficacy of ICIs, although some limitations exist. In addition to the PD-L1 tumor proportion score, many other clinical factors should also be considered to determine the optimal treatment strategy for each patient, including age, performance status, histological subtypes, comorbidities, status of oncogenic driver mutation, and metastatic sites. Nevertheless, evidence of the efficacy and safety of ICIs with some specific conditions of these factors is insufficient. Indeed, patients with poor performance status, oncogenic driver mutations, or interstitial lung disease have frequently been set as ineligible in randomized clinical trials of NSCLC. ICI use in these patients is controversial and remains to be discussed. It is important to select patients for whom ICIs can benefit the most from these populations. In this article, we review previous reports of clinical trials or experience in using ICIs in NSCLC, focusing on several clinical factors that are associated with treatment outcomes, and then discuss the optimal ICI treatment strategies for NSCLC.