Notch pathway regulates osimertinib drug-tolerant persistence in EGFR-mutated non-small-cell lung cancer.

Osimertinib is a third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) that has shown marked antitumor activity in patients with EGFR-mutated non-small-cell lung cancer (NSCLC). However, these effects are transient and most patients develop resistance. Reversible drug-tolerant persister (DTP) cells are defined as a small subpopulation of cells with markedly reduced sensitivity and non-genetic acquired resistance to EGFR-TKIs. Notch is a transmembrane receptor that plays an important role in tumorigenesis. We previously reported that there is significant crosstalk between the Notch and EGFR pathways in NSCLC. Moreover, the Notch pathway is associated with resistance to previous-generation EGFR-TKIs. However, the role of Notch in osimertinib resistance is not fully understood. In this study, we evaluated whether Notch is involved in osimertinib resistance. We show that NOTCH1 and Notch target genes are upregulated in osimertinib DTP cells, and that the addition of a γ-secretase inhibitor (GSI), a Notch inhibitor, impairs drug-tolerant persistence in vitro and in vivo. Compared with osimertinib, combined GSI and osimertinib suppress phospho-ERK partly by enhancing DUSP1 expression. Furthermore, Notch1 and HES1 were upregulated after EGFR-TKI treatment in half of human EGFR-mutated NSCLC tumor tissues. These results suggest that the combination of GSI and osimertinib may be a potential therapy for EGFR-mutated NSCLC.

Effects of obesity on CC16 and their potential role in overweight/obese asthma.

INTRODUCTION: Club cell secretory protein-16 (CC16) is a major anti-inflammatory protein expressed in the airway; however, the potential role of CC16 on overweight/obese asthma has not been assessed. In this study, we examined whether obesity reduces airway/circulatory CC16 levels using experimental and epidemiological studies. Then, we explored the mediatory role of CC16 in the relationship of overweight/obesity with clinical asthma measures. METHODS: Circulating CC16 levels were assessed by ELISA in three independent human populations, including two groups of healthy and general populations and asthma patients. The percentage of cells expressing club markers in obese vs. non-obese mice and human airways was determined by immunohistochemistry. A causal mediation analysis was conducted to determine whether circulatory CC16 acted as a mediator between overweight/obesity and clinical asthma measures. RESULTS: BMI was significantly and monotonously associated with reduced circulating CC16 levels in all populations. The percentage of CC16-expressing cells was reduced in the small airways of both mice and humans with obesity. Finally, mediation analysis revealed significant contributions of circulatory CC16 in the association between BMI and clinical asthma measures; 21.8% of its total effect in BMI's association with airway hyperresponsiveness of healthy subjects (p = 0.09), 26.4% with asthma severity (p = 0.030), and 23% with the required dose of inhaled corticosteroid (p = 0.042). In logistic regression analysis, 1-SD decrease in serum CC16 levels of asthma patients was associated with 87% increased odds for high dose ICS requirement (p < 0.001). CONCLUSIONS: We demonstrate that airway/circulating CC16, which is inversely associated with BMI, may mediate development and severity in overweight/obese asthma.

Phase II study of carboplatin-paclitaxel alone or with bevacizumab in advanced sarcomatoid carcinoma of the lung: HOT1201/NEJ024.

OBJECTIVES: Only a few prospective studies have been conducted to examine the efficacy and safety of systemic chemotherapy for patients with pulmonary sarcomatoid carcinomas (PSCs). There is, thus, a crucial need to develop novel treatment strategies for this rare tumor. PATIENTS AND METHODS: Chemotherapy-naïve patients with histologically confirmed PSCs were assigned to receive either carboplatin/paclitaxel alone (CP) or with bevacizumab (CPB) followed by bevacizumab maintenance. The primary endpoint was overall response rate (ORR). Secondary endpoints included overall survival (OS), progression-free survival (PFS), and safety. RESULTS: This study was closed before accumulating the expected number of cases due to slow patient accrual. Eventually, 16 patients were enrolled. The ORR was 25.0% and disease control rate was 56.3%. CPB was administered in all four patients with an objective response [partial response (PR)]; among the four PR cases, two patients had pleomorphic carcinoma, and two had carcinosarcoma. Median PFS and median survival time (MST) in all the enrolled patients were 2.6 months and 8.8 months, respectively. Median PFS was 1.2 months in the CP group and 4.2 months in the CPB group. In addition, MST was 7.9 months in the CP group and 11.2 months in the CPB group. Hematological and non-hematological adverse events were common and reversible, although ileus (grade 4) and nasal bleeding (grade 3) occurred in one case each in the CPB group. CONCLUSIONS: CPB might be effective as first-line treatment for PSCs. Further study is warranted to clarify the role of cytotoxic chemotherapy for this rare and aggressive tumor. CLINICAL TRIALS REGISTRATION: University Hospital Medical Information Network (UMIN) Clinical Trial Registry (UMIN000008707).

Risk of bleeding associated with transbronchial biopsy using flexible bronchoscopy in patients with echocardiographic or chest CT evidence of pulmonary hypertension.

BACKGROUND: Endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) facilitates the diagnosis of various respiratory diseases. The safety of performing EBUS-guided TBB in patients with a finding of pulmonary hypertension (PH) is controversial. Little is known about the relationship between the risk of bleeding associated with EBUS-guided TBB in the presence of PH suspected on echocardiography or chest CT. METHODS: To assess the risk of bleeding associated with EBUS-guided TBB in patients with presumed PH per echocardiography or chest CT, we retrospectively reviewed the medical records of 314 consecutive patients who underwent EBUS-guided TBB using a guide sheath (GS), as well as echocardiography and chest CT. Bleeding complication was defined as over one minute of suctioning; repeated wedging of the bronchoscope; instillation of cold saline, diluted vasoactive substances, or thrombin due to persistent bleeding. Findings of suspected PH were defined as peak tricuspid regurgitation velocity (TRV) > 2.8 m/s on echocardiography or pulmonary artery to aorta ratio (PA:A ratio) > 0.9 on chest CT. RESULTS: In total, 35 (11.1%) patients developed bleeding, and all cases were managed safely. Furthermore, 17 (5.4%) and 59 (18.8%) patients were suspected to have PH based on echocardiography and chest CT, respectively. Among the patients suspected to have PH on echocardiography, five (5/17 = 29.4%) patients developed bleeding. Among the patients suspected to have PH on chest CT, 11 (11/59 = 18.6%) patients developed bleeding. Univariate analysis revealed that long diameter (≥ 30 mm) of the lesion, lesion location (the biopsy site was inner than the segmental bronchus), bronchoscopic diagnosis of malignancy, and additional biopsy were potential predictive factors for bleeding. The finding of suspected PH on echocardiography correlated significantly with bleeding (p = 0.03). On multivariate analysis, long diameter (≥ 30 mm) of the lesion (p = .021) and findings of suspected PH on echocardiography (p = .049) were significantly associated with bleeding. CONCLUSION: All cases of bleeding in the present study were managed safely. The risk of bleeding is moderately elevated when PH is suspected by echocardiography in patients undergoing EBUS-guided TBB using a GS.

D-2-hydroxyglutarate produced by mutant IDH2 causes cardiomyopathy and neurodegeneration in mice.

Mutations in isocitrate dehydrogenase 1 and 2 (IDH1/2) have been discovered in several cancer types and cause the neurometabolic syndrome D2-hydroxyglutaric aciduria (D2HGA). The mutant enzymes exhibit neomorphic activity resulting in production of D2-hydroxyglutaric acid (D-2HG). To study the pathophysiological consequences of the accumulation of D-2HG, we generated transgenic mice with conditionally activated IDH2(R140Q) and IDH2(R172K) alleles. Global induction of mutant IDH2 expression in adults resulted in dilated cardiomyopathy, white matter abnormalities throughout the central nervous system (CNS), and muscular dystrophy. Embryonic activation of mutant IDH2 resulted in more pronounced phenotypes, including runting, hydrocephalus, and shortened life span, recapitulating the abnormalities observed in D2HGA patients. The diseased hearts exhibited mitochondrial damage and glycogen accumulation with a concordant up-regulation of genes involved in glycogen biosynthesis. Notably, mild cardiac hypertrophy was also observed in nude mice implanted with IDH2(R140Q)-expressing xenografts, suggesting that 2HG may potentially act in a paracrine fashion. Finally, we show that silencing of IDH2(R140Q) in mice with an inducible transgene restores heart function by lowering 2HG levels. Together, these findings indicate that inhibitors of mutant IDH2 may be beneficial in the treatment of D2HGA and suggest that 2HG produced by IDH mutant tumors has the potential to provoke a paraneoplastic condition.

Bromodomain and extraterminal domain inhibition synergizes with WEE1-inhibitor AZD1775 effect by impairing nonhomologous end joining and enhancing DNA damage in nonsmall cell lung cancer.

Bromodomain and extraterminal domain (BET) inhibitors are broadly active against distinct types of cancer, including nonsmall cell lung cancer (NSCLC). Previous studies have addressed the effect of BET-inhibiting drugs on the expression of oncogenes such as c-Myc, but DNA damage repair pathways have also been reported to be involved in the efficacy of these drugs. AZD1775, an inhibitor of the G2-M cell cycle checkpoint kinase WEE1, induces DNA damage by promoting premature mitotic entry. Thus, we hypothesized that BET inhibition would increase AZD1775-induced cytotoxicity by impairing DNA damage repair. Here, we demonstrate that combined inhibition of BET and WEE1 synergistically suppresses NSCLC growth both in vitro and in vivo. Two BET inhibitors, JQ1 and AZD5153, increased and prolonged AZD1775-induced DNA double-strand breaks (DSBs) and concomitantly repressed genes related to nonhomologous end joining (NHEJ), including XRCC4 and SHLD1. Furthermore, pharmaceutical inhibition of BET or knockdown of the BET protein BRD4 markedly diminished NHEJ activity, and the BET-inhibitor treatment also repressed myelin transcription factor 1 (MYT1) expression and promoted mitotic entry with subsequent mitotic catastrophe when combined with WEE1 inhibition. Our findings reveal that BET proteins, predominantly BRD4, play an essential role in DSB repair through the NHEJ pathway, and further suggest that combined inhibition of BET and WEE1 could serve as a novel therapeutic strategy for NSCLC.

DLL3 regulates the migration and invasion of small cell lung cancer by modulating Snail.

Delta-like protein 3 (DLL3) is a ligand of Notch signaling, which mediates cell-fate decisions and is tumor-suppressive or oncogenic depending on the cellular context. Previous studies show that DLL3 is highly expressed in small cell lung cancer (SCLC) but not in normal lung tissue, suggesting that DLL3 might be associated with neuroendocrine tumorigenesis. However, its role in SCLC remains unclear. To investigate the role of DLL3 in tumorigenesis in SCLC, we performed loss-of-function and gain-of-function assays using SCLC cell lines. In vitro analysis of cell migration and invasion by transwell assay showed that DLL3 knockdown reduced migration and invasion of SCLC cells, whereas DLL3 overexpression increased these activities. In addition, DLL3 positively regulated SNAI1 expression and knockdown of SNAI1 attenuated the migration and invasion ability of SCLC cells. Moreover, upregulated DLL3 expression induced subcutaneous tumor growth in mouse models. These results indicate that DLL3 promoted tumor growth, migration and invasion in an SCLC model by modulating SNAI1/Snail.

Combined antitumor effect of γ-secretase inhibitor and ABT-737 in Notch-expressing non-small cell lung cancer.

BACKGROUND: Inhibition of Notch by γ-secretase inhibitor (GSI) has been shown to have an antitumor effect in Notch-expressing non-small cell lung cancer (NSCLC) and to induce apoptosis through modulation of Bcl-2 family proteins. In particular, Bim, a BH3-only member of the Bcl-2 family of proteins, has an important role in the induction of apoptosis in NSCLC when cells are treated with GSI. ABT-737, a BH3-only mimetic, targets the pro-survival Bcl-2 family and also induces apoptosis. METHODS: The Notch-expressing NSCLC cell lines H460, A549, H1793, and HCC2429 were used. The combined antitumor effect of GSI and ABT-737 was evaluated using the MTT proliferation assay in vitro and in xenograft mouse models. The expression of the Notch pathway and Bcl-2 family was analyzed using Western blotting analysis when cells were treated with a single drug treatment or a combination treatment. RESULTS: GSI XX or ABT-737 alone inhibited cell proliferation in a dose-dependent manner, and combination drug treatment showed a synergistic antitumor effect in vitro. In vivo, this drug combination significantly suppressed tumor proliferation compared to the single drug treatment. Phospho-Bcl-2 was downregulated and Bax was upregulated by both the single and combination drug treatments. Bim was induced by a single drug treatment and was enhanced by combination treatment. Combination treatment-induced apoptosis was decreased by Bim inhibition, suggesting that the antitumor effect of the drug combination was dependent on Bim. CONCLUSION: Based on our data, we propose that the combination treatment is a promising strategy for NSCLC therapy.

CD133 expression: a potential prognostic marker for non-small cell lung cancers.

BACKGROUND: CD133 is a membrane glycoprotein containing five transmembrane loops. Previous reports suggest that a CD133-positive subpopulation of multipotent cells with extensive proliferative and self-renewal characteristics has biological features of a cancer stem cell. In addition, the presence of CD133-positive cells was associated with a significantly poorer prognosis for some solid tumors, compared to those with CD133-negative cells. However, the clinicopathological significance of CD133 in non-small cell lung cancer (NSCLC) remains controversial. METHODS: We conducted immunohistochemical assessment of 161 NSCLCs surgically resected at Hokkaido University Hospital between 1982 and 1994 to evaluate correlations between CD133 expression and various clinicopathological features. RESULTS: CD133 expression was significantly correlated with pathological stages (pStages) II, III, and IV for the various NSCLC types analyzed and was an independent factor for unfavorable prognosis in this population (hazard ratio = 3.157, P = 0.015). CONCLUSION: CD133 expression was correlated with pStage and was predictive of unfavorable prognosis in patients with pStages II, III, and IV NSCLC. These results suggest the possibility of using CD133 as a novel prognostic marker in these patients.

A phase II study of amrubicin as a third-line or fourth-line chemotherapy for patients with non-small cell lung cancer: Hokkaido Lung Cancer Clinical Study Group Trial (HOT) 0901.

Amrubicin, a third-generation synthetic anthracycline agent, has favorable clinical activity and acceptable toxicity for the treatment of patients with non-small cell lung cancer (NSCLC) and small cell lung cancer. We conducted this study to evaluate the efficacy and safety of amrubicin for advanced NSCLC patients as a third- or fourth-line therapy. Eligible patients had recurrent or refractory advanced NSCLC after second- or third-line therapy. Patients received amrubicin, 35 mg/m(2) i.v. on days 1-3 every 3 weeks. The primary endpoint was the disease control rate (DCR). Secondary endpoints were the overall survival (OS) time, progression-free survival (PFS) time, response rate, and toxicity profile. Of the 41 patients enrolled, 26 received amrubicin as a third-line and 15 received it as a fourth-line therapy. The median number of treatment cycles was two (range, 1-9). Objective responses were complete response (n = 0), partial response (n = 4), stable disease (n = 21), progressive disease (n = 15), and not evaluable (n = 1), resulting in a DCR of 61.0% (95% confidence interval, 46.0%-75.9%). The overall response rate was 9.8% (95% confidence interval, 0.6%-18.8%). The median PFS interval was 3.0 months, median OS time was 12.6 months, and 1-year survival rate was 53.7%. Grade 3 or 4 hematological toxicities were neutropenia (68%), anemia (12%), thrombocytopenia (12%), and febrile neutropenia (17%). Nonhematological toxicities were mild and reversible. No treatment-related deaths were observed. Amrubicin showed significant clinical activity with manageable toxicities as a third- or fourth-line therapy for patients with advanced NSCLC. This study provides relevant data for routine practice and future prospective trials evaluating third- or fourth-line treatment strategies for patients with advanced NSCLC.

Gefitinib-induced Myositis: A Novel Case Report.

Chemotherapy-induced myositis is a severe adverse event caused by chemotherapeutic agents such as immune checkpoint inhibitors (ICIs) or cytotoxic agents. We experienced a patient with gefitinib-induced myositis with symptoms of muscle cramps and stiffness in the limbs, and reported the treatment process. A 70-year-old woman received four courses of carboplatin (CBDCA)+pemetrexed (PEM)+gefitinib (intravenous CBDCA area under the curve (AUC) 5 and PEM 500 mg/m2, every 3 weeks, and oral gefitinib 250 mg daily), for epidermal growth factor receptor (EGFR) mutation-positive stage IV lung cancer treatment; followed by seven courses of PEM+gefitinib, and continued gefitinib monotherapy thereafter. Myositis occurred 5 months after the initiation of gefitinib monotherapy. She developed strong limb cramps despite regular oral administration of 400 mg acetaminophen three times a day and complained of pain on a numeric rating scale of 10/10. Her creatine kinase (CK) was elevated from the second course of CBDCA+PEM+gefitinib but was stable at grade 1-2 thereafter. However, the muscle symptoms disappeared with CK normalization within a few days of gefitinib discontinuation due to disease progression. The Naranjo Adverse Drug Reaction Scale score was 6, suggesting a probable association. Osimertinib (an EGFR tyrosine kinase inhibitor)-induced myositis has been reported, but similar events were first observed with gefitinib in this case. Consequently, when treating with gefitinib, myositis, including the CK variation, should be monitored and appropriately managed with multidirectional treatment.

Inhibition of non-homologous end joining mitigates paclitaxel resistance resulting from mitotic slippage in non-small cell lung cancer.

Mitotic slippage, which enables cancer cells to bypass cell death by transitioning from mitosis to the G1 phase without undergoing normal cytokinesis, is one likely mechanism of paclitaxel (PTX) resistance. DNA double-strand breaks (DSBs) in the G1 phase are mainly repaired through non-homologous end joining (NHEJ). Therefore, inhibiting NHEJ could augment the PTX-induced cytotoxicity by impeding the repair of PTX-induced DSBs during the G1 phase following mitotic slippage. We aimed to evaluate the effects of NHEJ inhibition on mitotic slippage after PTX treatment in non-small cell lung cancer (NSCLC). H1299, A549, H1975, and H520 NSCLC cell lines were employed. In addition, A-196 and JQ1 were used as NHEJ inhibitors. H1299 cells were PTX-resistant and exhibited an increased frequency of mitotic slippage upon PTX treatment. NHEJ inhibitors significantly augmented the PTX-induced cytotoxicity, DSBs, and apoptosis in H1299 cells. The newly generated PTX-resistant cells were even more prone to mitotic slippage following PTX treatment and susceptible to the combined therapy. Docetaxel further demonstrated synergistic effects with the NHEJ inhibitor in PTX-resistant cells. NHEJ inhibition may overcome intrinsic or acquired PTX resistance resulting from mitotic slippage by synergistically increasing the cytotoxic effects of antimitotic drugs in NSCLC.

The peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp-based test for epidermal growth factor receptor mutations in bronchoscopic cytological specimens of non-small cell lung cancer.

OBJECTIVES: Cytological examination of samples obtained by bronchoscopy is a useful method for establishing the diagnosis of non-small cell lung cancer (NSCLC). However, the utility of a highly sensitive method for the detection of epidermal growth factor receptor (EGFR) mutation in the cytological specimens has not been fully evaluated. METHODS: We retrospectively examined the efficacy of the peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp method for detecting EGFR mutations in 122 bronchoscopic cytological specimens from NSCLC patients. RESULTS: Overall, 41 specimens (33.6%) were positive for EGFR mutation. Twenty-nine (39.7%) of 73 specimens obtained by using endobronchial ultrasonography with a guide sheath, 7 (33.3%) of 21 specimens obtained under direct vision by using a conventional bronchoscope, 4 (36.4%) of 11 specimens obtained by using an ultrathin bronchoscope, and 1 (5.9%) of 17 specimens obtained by endobronchial ultrasound-guided transbronchial needle aspiration were positive for EGFR mutation. Furthermore, among 22 resected NSCLC cases, the EGFR mutation status obtained from bronchoscopic materials was consistent with the status obtained from surgical samples, with the exception of 1 case. CONCLUSION: The detection of EGFR mutation by subjecting bronchoscopic cytological specimens to a PNA-LNA PCR clamp assay proves useful.

Expression of Bim, Noxa, and Puma in non-small cell lung cancer.

BACKGROUND: The BH3-only members of the Bcl-2 protein family have been proposed to play a key role in the control of apoptosis and in the initiation of the apoptotic pathways. In this study, we evaluated the expression of Bim, Noxa, and Puma in non-small cell lung cancer (NSCLC). METHODS: A total of 135 surgically resected NSCLCs were immunohistochemically assessed for Bim, Noxa, and Puma expression. The immunoscores were determined, and then its correlation with either the clinicopathological variables or the survival outcomes were analyzed. RESULTS: Immunohistochemical reactivity for Bim, Noxa, and Puma was detected in the cytoplasm of the tumor cells. Bim expression was associated with several clinicopathological factors, including sex (p < 0.001), smoking habit (p = 0.03), pathological histology (p = 0.001), pathological T stage (p = 0.03), pathological disease stage (p = 0.02), and differentiation of tumor (p < 0.001). Multivariate logistic regression analysis showed a significant correlation between low Bim expression and squamous cell carcinoma (p = 0.04), in addition to a correlation between high Bim expression and well differentiated tumors (p = 0.02). Analysis of cellular biological expression demonstrated a link between low Bim expression and high Ki67. While Noxa expression was also shown to be correlated with both smoking habit (p = 0.02) and the pathological histology (p = 0.03), there was no strong association observed between the expression and the clinical features when they were examined by a multivariate logistic regression analysis. No correlations were noted between Puma expression and any of the variables. Our analyses also indicated that the expression levels of the BH3-only proteins were not pertinent to the survival outcome. CONCLUSIONS: The current analyses demonstrated that Bim expression in the NSCLCs was associated with both squamous cell carcinoma histology and tumor proliferation.

Phase II study of irinotecan plus S-1 combination for previously untreated advanced non-small cell lung cancer: Hokkaido Lung Cancer Clinical Study Group Trial (HOT) 0601.

OBJECTIVE: Platinum-free regimens can represent an alternative for advanced non-small cell lung cancer (NSCLC) if similar efficacy is provided with better tolerability. This study evaluated the efficacy and safety of combined irinotecan and S-1 for chemotherapy-naïve advanced NSCLC. METHODS: Chemotherapy consisted of 4-week cycles of intravenous irinotecan (100 mg/m(2), days 1 and 15) and oral S-1 (80 mg/m(2), days 1-14). The primary endpoint was response rate, while secondary endpoints were overall survival, progression-free survival (PFS), and safety. RESULTS: A total of 112 cycles was administered to 40 patients (median 3 cycles; range 1-6 cycles). Twelve patients showed partial response and 17 patients had stable disease, representing a response rate of 30% and a disease control rate of 72.5%. Median survival time and median PFS were 16.1 and 4.8 months, respectively. Hematological toxicities of grade 3 or 4 were neutropenia (32.5%) and anemia (5.0%). The most common nonhematological toxicities of grade 3 or 4 included diarrhea (15.0%) and anorexia (17.5%). Patients homo- or heterozygous for UGTA1A*6 tended to show a higher incidence of grade 3 diarrhea (p = 0.055). CONCLUSION: The combination of irinotecan and S-1 offers good efficacy and tolerability for previously untreated advanced NSCLC.

Elevated serum CYFRA 21-1 level as a diagnostic marker for thymic carcinoma.

BACKGROUND: No useful tumor markers have been identified for the diagnosis of thymic carcinomas. Serum cytokeratin 19 fragment, measured using the CYFRA 21-1 immunoassay, is used as a tumor marker for squamous cell carcinomas in various malignant tumors. Here, we evaluated the value of CYFRA 21-1 in diagnosing thymic carcinoma. METHODS: We retrospectively reviewed 94 patients with pathological diagnoses of thymic carcinoma or thymoma (32 and 62 patients, respectively) who were referred to our departments between January 2000 and March 2019. Primary outcomes included tumor marker levels and their diagnostic accuracy. RESULTS: Patients with thymic carcinoma were significantly more likely to be male (thymic carcinoma, 68.8%; thymoma, 40.3%; p = 0.02), have an advanced TNM stage (p < 0.01), and a significantly higher CYFRA 21-1 level than those with thymoma (thymic carcinoma: median = 4.2 ng/ml; interquartile range [IQR] = 2.1-6.1 ng/ml vs. thymoma: median = 1.2 ng/ml; IQR = 0.9-1.7 ng/ml; p < 0.01). Receiver operating characteristic curves demonstrated that the area under the curve for CYFRA 21-1 to distinguish thymic carcinoma from thymoma was 0.86 (95% confidence interval [CI]: 0.74-0.93; cutoff = 2.7 ng/ml; sensitivity = 68.8%; specificity = 95.2%). Multivariable analysis demonstrated that CYFRA 21-1 (odds ratio = 25.6; 95% CI: 4.6-141.6; p < 0.01) was an independent predictor for thymic carcinoma after adjusting for TNM stage. CONCLUSIONS: Serum CYFRA 21-1 level may help in diagnosing thymic carcinoma.

Randomized phase 2 study comparing irinotecan versus amrubicin as maintenance therapy after first-line induction therapy for extensive disease small cell lung cancer (HOT1401/NJLCG1401).

BACKGROUND: A cisplatin plus irinotecan (CPT-11) regimen is used for patients with extensive disease small cell lung cancer (ED-SCLC). Amrubicin (AMR) is primarily used for relapsed SCLC. The HOT1401/NJLCG1401 trial, an open-label randomized phase II trial, was designed to assess the benefit of maintenance therapy in patients with ED-SCLC who responded to induction therapy. METHODS: Patients with histologically- or cytologically-confirmed ED-SCLC were included and were treated with an induction therapy of four cycles of cisplatin (60 mg/m2 on day 1) plus CPT-11 (60 mg/m2 on days 1, 8, and 15) every four weeks. After induction therapy, patients who had nonprogressive disease were randomized to receive either maintenance CPT-11 (60 mg/m2 on days 1 and 8) every three weeks, or AMR (35 mg/m2 on days 1-3) every three weeks. RESULTS: A total of 34 patients were enrolled; 20 patients had progressive disease or received incomplete induction chemotherapy. Finally, 14 patients were randomly assigned to receive CPT-11 (n = 7) or AMR (n = 7). This study was terminated prematurely because of low patient accrual. The overall objective response rate was 73%, the median PFS was 5.7 months (95% confidence interval [CI]: 3.6-11.8), and the median overall survival was 20.1 months (95% CI: 13.7-not reached). No statistically significant difference in progression-free survival (PFS) were noted between patients treated with CPT-11 and those treated with AMR. There were no treatment-related deaths in this study. CONCLUSIONS: Maintenance therapy with CPT-11 or AMR after induction therapy might be effective in some patients.

A case of radio-insensitive SMARCA4-deficient thoracic undifferentiated carcinoma with severe right heart failure.

SMARCA4-deficient thoracic sarcomatoid tumors were characterized by inactivating mutations of SMARCA4 and often found in the chest of young and middle-aged males with a smoking history. Recently, SMARCA4-deficient thoracic sarcomatoid tumors were reported to represent primarily smoking-associated undifferentiated/de-differentiated carcinomas rather than primary thoracic sarcomas. The main complication of this tumor is compression of the respiratory tract and/or blood vessels. A 39-year-old man presented with a 2-month history of fever and dyspnea. Computed tomography revealed a mediastinal tumor invading the right and left pulmonary arteries. Because of severe right heart failure, we considered him ineligible for bronchoscopy. We scheduled palliative irradiation with 40 Gy/20 Fr to improve hemodynamics and perform endobronchial ultrasound transbronchial needle aspiration later. However, irradiation was ineffective, and his general condition deteriorated quickly and he died after a 7-week hospitalization. An autopsy revealed that the diagnosis was SMARCA4-deficient thoracic undifferentiated carcinoma. It has been reported that this tumor is insensitive to radiotherapy and there were some cases which responded to an immune checkpoint inhibitor. Therefore, when caring for patients with mediastinal tumors that invade and compress the trachea and large vessels, it is important to consider this tumor as a differential diagnosis and try to make a pathological diagnosis as soon as possible.

CD8+ tumor-infiltrating lymphocytes predict favorable prognosis in malignant pleural mesothelioma after resection.

Defects in human leukocyte antigen (HLA) class I expression may allow tumor cells to escape immune recognition. T cell infiltration is associated with a good prognosis in many cancers. However, the role of HLA class I expression and tumor-infiltrating lymphocytes (TILs) in malignant pleural mesothelioma (MPM) has not been fully analyzed. In the present study, we investigated the immune profiles and conducted outcome analyses of MPM patients. HLA class I expression and TILs (CD4(+), CD8(+), and NK cells) were detected by immunohistochemistry in a series of 44 MPM cases. To detect HLA class I expression, specimens were stained with the anti-pan HLA class I monoclonal antibody EMR8-5. The expression of HLA class I was positive in all patients. There was no case that showed negative HLA class I expression. The density of CD4(+) and CD8(+) TILs were strongly correlated (R = 0.76, p < 0.001). A high density of CD8(+) TILs was a significantly better prognostic factor for the survival of patients with extrapleural pneumonectomy (p < 0.05). Multivariate analysis revealed that a high density of CD8(+) TILs is an independent prognostic factor for patients who underwent extrapleural pneumonectomy. The presence of intratumoral CD8(+) T cells was correlated with an improved clinical outcome, raising the possibility that CD8(+) T cells might play a pivotal role in the antitumor immune response against MPMs. Thus, the stimulation of CD8(+) lymphocytes might be an efficacious immunotherapy for MPM patients.

Evaluating the immunoproteasome as a potential therapeutic target in cisplatin-resistant small cell and non-small cell lung cancer.

PURPOSE: We evaluated the expression of proteasome subunits to assess whether the proteasome could be a therapeutic target in cisplatin-resistant lung cancer cells. METHODS: Cisplatin-resistant (CR) variants were established from three non-small cell lung cancer (NSCLC) cell lines (A549, H1299, and H1975) and two small cell lung cancer (SCLC) cell lines (SBC3 and SBC5). The expression of proteasome subunits, the sensitivity to immunoproteasome inhibitors, and 20S proteasomal proteolytic activity were examined in the CR variants of the lung cancer cell lines. RESULTS: All five CR cell lines highly expressed one or both of the immunoproteasome subunit genes, PSMB8 and PSMB9, while no clear trend was observed in the expression of constitutive proteasome subunits. The CR cells expressed significantly higher levels of PSMB8 and PSMB9 proteins, as well. The CR variants of the H1299 and SBC3 cell lines were more sensitive to immunoproteasome inhibitors, and had significantly more proteasomal proteolytic activity than their parental counterparts. CONCLUSIONS: The immunoproteasome may be an effective therapeutic target in a subset of CR lung cancers. Proteasomal proteolytic activity may be a predictive marker for the efficacy of immunoproteasome inhibitors in cisplatin-resistant SCLC and NSCLC.