IntroductionFor patients with T2aN0 stage IB lung adenocarcinoma, benefits of adjuvant chemotherapy remain controversial. Here, we aimed to evaluate such benefits.MethodsThis retrospective cohort study was conducted on the database of the National Taiwan Cancer Registry. We analyzed patients with T2aN0 stage IB lung adenocarcinoma (re-classified by AJCC 8th edition) diagnosed during the period from January 2011 to December 2017. They were divided into two groups: (1) group 1: tumor <=3 cm with visceral pleural invasion (VPI); (2) group 2: tumor >3 cm, but <=4 cm. Overall survival (OS) and cancer specific survival (CSS) were evaluated. Risk factors for survival were determined.ResultsA total of 2,100 patients with T2aN0 stage IB lung adenocarcinoma (1,265 in group 1 and 835 in group 2) were enrolled for study. The proportions of patients receiving adjuvant chemotherapy in group 1 and 2 were 39.1% and 68.6%, respectively. Amongst group 1 patients, adjuvant chemotherapy was not an independent risk factor for OS and CSS. Amongst group 2 patients, high-grade histologic findings and receiving sublobar resection were two risk factors for poorer survival. Adjuvant chemotherapy was also associated with an OS (adjusted hazard ratio (aHR), 0.52; 95% confidence interval (CI), 0.38-0.72; P<0.001) and CSS (aHR, 0.54; 95% CI, 0.37-0.78; p=0.001) benefit regardless of the presence or absence of risk factors.ConclusionFor patients with T2aN0 stage IB lung adenocarcinoma, adjuvant chemotherapy improved OS and CSS in those with tumors >3 cm, but <=4 cm.For patients with tumors <=3 cm with VPI, adjuvant chemotherapy had no survival benefit.

The impact of strong Programmed Death-ligand 1 (PD-L1) expression on the clinical outcomes of osimertinib in treatment naïve advanced Epidermal Growth Factor Receptor (EGFR) -mutant Non-small Cell Lung Cancer (NSCLC) patients remains uncertain. We enrolled advanced NSCLC patients who harbored sensitizing EGFR mutation and were treated first-line with osimertinib between 2017 and 2021. The PD-L1 expression level was also tested. A total of 85 patients were included. The objective response rate to osimertinib was 78.9%, with the disease control rate being 90.8%. Median Progression-free Survival (PFS) was 22.1 months, while median Overall Survival (OS) was not reached (NR). Patients with the exon 19 deletion experienced better PFS than those with the exon 21 L858R mutation (NR vs 12.4 months, aHR 0.24 (95% CI, 0.10 to 0.57); p = 0.001). Seventy-one of these 85 patients had reported on their PD-L1 expression. Patients with a PD-L1 < 50% experienced longer PFS than patients with a PD-L1 ≧50% (26.5 vs 9.7 months, aHR 0.19 (95% CI, 0.06 to 0.67); p = 0.009). Additionally, patients with a PD-L1 < 50% experienced better OS than those with a PD-L1 ≧50% (NR vs 25.4 months, aHR 0.09 (95% CI, 0.01 to 0.70); p = 0.021). Strong expressions of PD-L1 in treatment naïve advanced EGFR -mutant NSCLC patients were associated with poor prognoses in those undergoing treatment with osimertinib as first-line therapy.

We aimed to evaluate whether different driver mutations have varying impacts on the programmed cell death-ligand 1 (PD-L1) expression of non-small cell lung cancer (NSCLC), and whether the prognostic roles of PD-L1 amongst our patients were divergent. This was a single-institute study that included patients with NSCLC. Six driver mutations, PD-L1 status, and the outcomes of treatment were assessed. A total of 1,001 NSCLC patients were included for analysis. Overall, the PD-L1 positive (TPS ≥ 1%) and strong positive (TPS ≥ 50%) rates were 52.2% and 17.3%, respectively. As compared with wild type lung adenocarcinoma, EGFR-mutant and HER2-mutant patients had similarly low PD-L1 and strong PD-L1 positive rates. BRAF-mutant patients had numerically higher PD-L1 and strong PD-L1 positive rates. Patients with fusion mutation (ALK and ROS1) (aOR 2.32 [95% CI 1.10-4.88], P = 0.027 and 2.33 [95% CI 1.11-4.89], P = 0.026), KRAS mutation (aOR 2.58 [95% CI 1.16-5.75], P = 0.020 and 2.44 [95% CI 1.11-5.35], P = 0.026), and non-adenocarcinoma histology (aOR 2.73 [95% CI 1.72-4.34], P < 0.001 and 1.93 [95% CI 1.13-3.30], P = 0.016) all had significantly higher PD-L1 and strong PD-L1 positive rates. A trend towards longer survival was noted in ROS-1 rearranged and KRAS-mutant patients with strong PD-L1 expression who had received crizotinib and chemotherapy, respectively. In conclusion, individual driver mutations had various impacts on the PD-L1 expression of NSCLC patients. The prognostic role of PD-L1 may also be divergent amongst patients harboring different driver mutations.

Objective Immunotherapy plus etoposide and platinum (EP)-based chemotherapy is the standard of care for patients with extensive stage–small cell lung carcinoma (ES-SCLC). In the era of immunotherapy, the role of thoracic radiotherapy for ES-SCLC remains unclear. Methods We retrospectively included ES-SCLC patients treated with first-line EP-based chemotherapy plus atezolizumab or durvalumab at Taichung Veterans General Hospital to evaluate the prognostic role and safety of thoracic radiotherapy. Results A total of 22 patients were included. The median age was 64 years and most of them were male and smokers. Sixteen patients (72.7%) received durvalumab, while the other 6 patients (27.3%) underwent atezolizumab treatment. Among these patients, 11 (50.0%) had a history of thoracic radiotherapy. There was no significant difference in baseline characteristics between patients with and without thoracic radiotherapy. In the overall population, the objective response rate to immunotherapy plus chemotherapy was 73.7%. The progression-free survival and overall survival were 6.0 months (95% CI: 4.0–7.9) and 13.8 months (95% CI: 8.0–19.6), respectively. The overall survival was significantly longer in patients with thoracic radiotherapy (not-reached [NR] [95% CI NR-NR] vs. 9.6 months [95% CI 2.5–16.6]), respectively ( P value by log-rank test <0.001). Both multivariate analysis and subgroup analysis specifically comparing patients with consolidative thoracic radiotherapy and patients with clinical benefits to systemic therapy who did not undergo thoracic radiotherapy indicated that thoracic radiotherapy improved survival. Conclusion The real-world efficacy of EP-based chemotherapy plus atezolizumab or durvalumab was comparable with that of clinical trials. Thoracic radiotherapy may improve the outcome of ES-SCLC.

(1) Background: We aimed to evaluate the risk of hepatitis B virus (HBV) reactivation in lung cancer patients treated with tyrosine kinase inhibitor (TKI), particularly in those with resolved HBV infection. (2) Methods: In this retrospective hospital-based cohort study, we screened all lung cancer patients with positive hepatitis B core antibodies (anti-HBc) receiving systemic antineoplastic treatment during the period from January 2011 to December 2020. Cumulative incidences of HBV reactivation, and their hazard ratios (HRs), were evaluated after adjusting patient mortality as a competing risk. (3) Results: Among 1960 anti-HBc-positive patients receiving systemic therapy, 366 were HBsAg-positive and 1594 were HBsAg-negative. In HBsAg-positive patients without prophylactic NUC, 3-year cumulative incidences of HBV reactivation were similar between patients receiving chemotherapy and patients receiving TKI (15.0%, 95% confidence interval (CI): 0–31.2% vs. 21.2%, 95% CI: 10.8–31.7%; p = 0.680). Likewise, 3-year cumulative incidences of HBV-related hepatitis were similar between the two groups (chemotherapy vs. TKI: 15.0%, 95% CI: 0–31.2% vs. 9.3%, 95% CI: 2.8–15.7%; p = 0.441). In 521 HBsAg-negative TKI users, the 3-year cumulative incidence of HBV reactivation was only 0.6% (95% CI: 0.0–1.9%). From multivariable regression analysis, we found that the only independent risk factor for HBV reactivation in TKI users was HBsAg positivity (HR 53.8, 95% CI: 7.0–412.9; p < 0.001). (4) Conclusion: Due to high risks of HBV reactivation in HBsAg-positive TKI users, NUC prophylaxis can be considered. However, in patients with resolved HBV infection, such risks are lower, and therefore regular monitoring is recommended.

Abstract Background Antiangiogenic therapy is widely used in advanced non-small cell lung cancer (NSCLC) patients. The purpose of this study was to investigate the incidence, risk factors, and outcome of advanced NSCLC patients receiving antiangiogenic therapy with thromboembolic events (TE). Methods This was a retrospective study, which included advanced NSCLC patients receiving antiangiogenic therapy from March 2013 to May 2021 at Taichung Veterans General Hospital. All TE were confirmed by objective image studies. We further categorized TE into disease-related and treatment-related according to the tumor control status when TE occurred. Results A total of 427 patients were included. The overall incidence of TE was 10.1% (n = 43); among these patients, 28 (6.6%) and 15 (3.5%) patients were categorized into disease- and treatment-related TE, respectively. Multivariate analysis suggested that the use of hormone and proteinuria independently predicted a higher TE incidence among patients with disease-related TE (adjusted odds ratio [aOR] 2.79 [95% CI 1.13 = 6.92]; P = 0.027) and treatment-related TE (aOR 4.30 [95% CI 1.13–16.42]; P = 0.033), respectively. As compared with patients without TE, disease-related TE significantly predicted a shorter median overall survival (21.6 vs. 31.4 months, adjusted hazard ratio [aHR] 1.30 [95% CI 1.05–1.61]; P = 0.017), but patients with treatment-related TE had comparable survival time (32.7 vs. 31.4 months; aHR 1.05 [95% CI 0.57–1.61]; P = 0.876). Conclusion Patients receiving antiangiogenic therapy with TE should be further differentiated whether it is treatment- or disease-related, because the two groups had different risk factors and influences on outcome.

Background: The relative importance of predictive factors for advanced non-small cell lung cancer (NSCLC) patients on epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment remains unclear. Materials and methods: We retrospectively enrolled advanced NSCLC patients with single first-generation EGFR-TKI treatment for ⩾5 years (Y) in Taiwan. Clinical data was collected and compared with those of another cohort with single first-line EGFR-TKI treatment for <5 Y. Plasma cell-free DNA (cfDNA) samples were collected from patient subsets, pre- and post-TKI, in the >5 Y group. Results: Overall, 128 and 278 patients were enrolled in the ⩾5 Y and <5 Y groups, respectively. Significant factors in the multivariate analysis of patients’ characteristics including Eastern Cooperative Oncology Group performance status 0–1, postoperative recurrence, without brain metastasis, oligometastasis (each score of 2), female sex, erlotinib use, and without bone metastasis (each score of 1), were incorporated into a risk scoring system. The area under the receiver operating characteristic curve was 0.82 [95% confidence interval (CI): 0.78–0.86]. Of the plasma cfDNA samples from 33 patients in the ⩾5 Y group, only 1 had a T790M in 25 patients without progressive disease. In 27 patients with single agent use for ⩾96 months, 22 (81.5%) received local treatment (surgery or radiotherapy) for the primary lung tumor before and during TKI treatment. Conclusion: For NSCLC patients with single first-generation EGFR-TKI use for ⩾5 Y, factors with different relative importance exist and the risk-scoring model is feasible with modest accuracy. The role of local treatment for primary tumors in patients with long-term TKI use requires further investigation.

Pleural effusion is a rare immune-related adverse event for lung cancer patients receiving immune checkpoint inhibitors (ICIs). We enrolled 281 lung cancer patients treated with ICIs and 17 were analyzed. We categorized the formation of pleural effusion into 3 patterns: type 1, rapid and massive; type 2, slow and indolent and type 3, with disease progression. CD4/CD8 ratio of 1.93 was selected as the cutoff threshold to predict survival. Most patients of types 1 and 2 effusions possessed pleural effusion with CD4/CD8 ratios > = 1.93. The median OS time in type 1, 2, and 3 patients were not reached, 24.8, and 2.6 months. The median PFS time in type 1, 2, and 3 patients were 35.5, 30.2, and 1.4 months. The median OS for the group with pleural effusion CD4/CD8 > = 1.93 and < 1.93 were not reached and 2.6 months. The median PFS of those with pleural effusion CD4/CD8 > = 1.93 and < 1.93 were 18.4 and 1.2 months. In conclusion, patients with type 1 and 2 effusion patterns had better survival than those with type 3. Type 1 might be interpreted as pseudoprogression of malignant pleural effusion. CD4/CD8 ratio > = 1.93 in pleural effusion is a good predicting factor for PFS.

BACKGROUND/PURPOSE:Lung cancer patients can have advanced-stages at diagnosis, even the tumor size is ≤2 cm. We aimed to study the relationship between image characteristics, clinical, and patholoigcal results. METHODS:We retrospectively enrolled patients with lung adenocarcinoma at Taichung Veterans General Hospital and Chang Gung Memorial Hospital from 2007 to 2015, who were diagnosed with treatment naïve primary tumor lesions at sizes less than 2 cm, as measured by computed tomography (CT) scans. The patient was analyzed for lymph node (LN) and distant metastasis evaluation, with clinicopathological characteristics, including tumor-disappearance ratio (TDR) (tumor diameter at the mediastinal/lung window) over chest CT scans, pathological diagnosis, disease-free survival (DFS), and overall survival (OS). RESULTS:Totally 280 patients were surveyed initially and showed significantly increase of clinical LN involvement and distant metastasis when TDR ≤75% compared with >75% (21.6% vs 0% for LN involvement; 27.1% vs 0% for distant metastasis; both p < 0.001). We included 199 patients having surgical treatment and follow-up for the survival analysis. With a TDR ≤75%, significantly worse DFS (HR, 19.23; 95% CI, 2.60-142.01; p = 0.004) and a trend of worse OS (HR, 4.97; 95% CI, 0.61-40.61; p = 0.134) were noted by Kaplan-Meier method. TDR ≤75% revealed more advanced pathological stage, and more tumors containing micropapillary or solid subtypes when diagnosed adenocarcinoma. CONCLUSION:For lung cancer patients with primary tumor ≤2 cm, TDR ≤75% was related to more advanced stages, the presence of micropapillary or solid components of adenocarcinoma subtypes, worse DFS, and a trend of worse OS.

Enolase transforms 2-phospho-D-glycerate into phosphoenolpyruvate during glycolysis. The human enolase (ENO) family comprises three members named ENO3, which is restricted to muscle tissues, ENO2, which is neuron- and neuroendocrine tissue-specific, and ENO1, which is expressed in almost all tissues. ENO1 is involved in various types of human cancer, including retinoblastoma, hepatocellular carcinoma, pancreatic cancer, renal cell carcinoma, cholangiocarcinoma and gastric cancer. Furthermore, ENO1 enhances cell transformation in numerous cancer cell lines. It has been reported that ENO1 is involved in various activities that are detrimental to cell transformation, including apoptosis and differentiation. However, a few studies demonstrated that ENO1 can be down- or upregulated in various types of lung cancer, which suggests that ENO1 has an ambiguous role in the development of lung cancer. The present study aimed to investigate the differential influences of ENO1 on various types of cancer, and to clarify the role of ENO1 in lung cancer in particular. Western blotting was performed to assess ENO1 protein expression levels in lung cancer and esophageal cancer tissues. Furthermore, exogenous ENO1 was overexpressed in cell lines derived from various tissues and single cell proliferation, flowcytometric analysis, and western blotting were performed to determine the cell proliferation rate, cell transformation status, cell cycle progression and the expression of cell cycle regulators, such as cyclins and cyclin-dependent kinases, and survival factors, such as MAPK and AKT. The results demonstrated that ENO1 was upregulated in collected panels of lung cancer tissues, but not in esophageal cancer tissues. In addition, overexpression of ectopic ENO1 promoted cell proliferation and survival in lung cancer cell lines, which was not the case in other cells, including an esophageal cell line. Furthermore, mechanistic analyses revealed that ENO1 enhanced cell proliferation by accelerating G(1) progression and upregulating G(1) phase cyclin-dependent kinase 6 (CDK6), and improved cell survival by upregulating p38 in the MAPK cascade and increasing p-AKT in the AKT cascade, in particular in lung cancer cell lines. Overall, the results from the present study demonstrated that ENO1 may contribute to the development of lung cancers, but not esophageal cancers.

RAGE (receptor for advanced glycation end-product) is thought to be associated with metastasis and poor prognosis of various types of cancer. However, RAGE is constitutively expressed in the normal lung and down-regulated in cancerous lung, while the opposite evidence shows that RAGE-mediated signaling contributes to the tumorigenesis of lung cancer. Therefore, the role of RAGE in lung cancer progression is still unclear to be further investigated. In this study, RAGE-overexpressed stable clones of human lung cancer A549 cells and two local lung adenocarcinoma cell lines CL1-0 and CL1-5 were utilized to verify the effect of RAGE on lung cancer cells while the in vivo xenograft animal model was further performed to evaluate the role of RAGE in the progression of lung cancer. The growth of A549 cells was inhibited by RAGE overexpression. p53-dependent p21CIP1 expression contributed to RAGE-induced growth inhibition by suppressing CDK2 kinase activity and retinoblastoma protein (RB) phosphorylation in vitro. On the other hand, RAGE overexpression promoted migration, invasion, and mesenchymal features of lung adenocarcinoma cells through ERK signaling. Furthermore, an in vivo xenograft experiment indicated that RAGE promoted the metastasis of lung cancer cells with p21CIP1 up-regulation, ERK activation, and the changes of EMT markers. Regarding to the involvement of tumor-associated macrophage (TAM) in the microenvironment, we monitored the expressions of TAM markers including CD68 and CD163 as well as angiogenesis marker CD31 in xenograft slice. The data showed that RAGE might induce the accumulation of TAM in lung cancer cells and further accelerate the in vivo tumor growth. In summary, our study provides evidence indicating the distinct in vitro and in vivo effects of RAGE and related mechanisms on tumor growth and metastasis, which shed light on the oncogenic role of RAGE in lung cancer.

Objectives: The characteristics and efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) in advanced EGFR-mutant lung adenocarcinoma patients with primary tumor resection (PTR) is not yet clear. Methods: We enrolled advanced EGFR-mutant lung adenocarcinoma patients with EGFR-TKI as first-line therapy to access the impact of PTR on the outcomes. Results: A total of 466 patients were enrolled with 76 patients (16.3%) undergoing PTR; 59 patients recurred after curative surgery, while 17 patients underwent surgery as diagnostic purposes. PTR patients displayed a better performance status, a lower metastatic burden, and much less measurable diseases (30.3 vs. 97.4%, p < 0.001). PTR patients experienced a significantly longer progression-free survival (25.1 [95% CI 16.6-33.7] vs. 9.4 [95% CI 8.4-10.4] months; aHR 0.40 [95% CI 0.30-0.54], p < 0.001) and overall survival (56.8 [95% CI 36.3-77.2] vs. 31.8 [95% CI 28.2-35.4] months; aHR 0.57 [95% CI 0.39-0.84], p = 0.004). Survival advantage was still observed while comparing PTR patients with the better performance and lower metastatic burden subgroup found within the non-resection group. Moreover, the progression-free survival and overall survival of 11 patients who were found having pleural metastases during surgery and underwent PTR plus pleural biopsy, were also longer than those with pure N0--1/M1a-malignant pleural effusion disease in the non-resection group (n = 19) (p < 0.001 and p = 0.002, respectively). Conclusion: PTR was associated with significantly better outcomes in advanced lung adenocarcinoma patients treated with EGFR-TKI. Further studies are needed to evaluate the biological role of PTR among these patients.

It remains unclear how programmed death-ligand 1 (PD-L1) expression interacts with anaplastic lymphoma kinase ( ALK ) mutation, its variants, and the outcome of treatment. One hundred and twenty four out of 1255 patients (9.9%) were deemed ALK -positive by the Ventana IHC assay. PD-L1 status and ALK variants were available in 100 and 59 patients, respectively. PD-L1 positive (TPS ≥ 1%) and strong positive (TPS ≥ 50%) rate was 50% and 16%, respectively. A total of 64 variant types were detected in 59 patients. V1 (32.8%) and V3a/b (28.1%) were the most common variants. There was no significant association between ALK variants and the PD-L1 expression. The presence of V3a/b subtype independently predicted a worse overall survival in patients receiving ALK inhibitor(s) (aHR 5.10 [95% CI 1.22–21.25], P = 0.025) and platinum plus pemetrexed (aHR 9.62 [95% CI 1.90–48.80], P = 0.006). While incorporating ALK variants and PD-L1 expression together, patients with non-V3a/b/positive PD-L1 showed a trend towards longer OS. In conclusion, ALK -positive NSCLC patients possess a high PD-L1 expression rate. Although there was no significant association between PD-L1 expression and ALK variants, the outcome of ALK -positive patients could be sorted by these two biomarkers.

Protein phosphorylation plays roles in cell transformation. Numerous protein kinase enzymes actively participate in the formation of various types of cancer by phosphorylating downstream substrates. Aurora‑A is a widely known Serine/Threonine (Ser/Thr) oncogenic kinase, which is upregulated in more than twenty types of human cancer. This enzyme phosphorylates a wide range of substrates. For example, Aurora‑A induces cell transformation by phosphorylating hepatoma upregulated protein (HURP) at four serine residues, which in turn decreases the phosphorylated levels of cell‑growth suppressive Jun N‑terminal kinase (p‑JNK). Various protein phosphatase enzymes are considered tumor suppressors by the dephosphorylation and consequent inactivation of their oncogenic substrates. Protein phosphatase 1α (PP1α), for instance, acts on Aurora‑A by dephosphorylating its substrates. However, the role of PP1α in cancer progression remains ambiguous. PP1α is overexpressed in several cancer tissues, and induces cell apoptosis and differentiation or it inhibits tumor formation in other types of cells. In addition, positive and negative correlations between PP1α expression and lung cancer development have been documented. These observations suggest the differential regulation of PP1α in various cancer tissues, or propose an ambiguous contribution of PP1α to lung cancer development. In order to investigate these contradictory conclusions, it was reported that the chromosomal region covering the PP1α locus was subjected to DNA alterations, such as gain or loss in various human cancer types by a study based on literature search. Upregulation of PP1α was noted in a collection of lung cancer tissues, and was required for the cell transformation of the lung cancer cell line A549. In contrast to this finding, overexpression of ectopic PP1α inhibited cell proliferation in 293T cells. Mechanistic studies revealed that PP1α activated AKT in A549 cells, whereas it further inactivated AKT and disrupted the HURP/JNK signaling cascade in 293T cells. Collectively, the data indicated that PP1α exerted an oncogenic function in lung cancer, while exhibiting various effects on cell transformation in different types of cells via distinct or opposite mechanisms.

PURPOSE:In the current targeted therapy era, information on the effect of smoking in epidermal growth factor receptor (EGFR)-mutant lung cancer patients is scarce.RESULTS:In total, 11,678 adenocarcinoma patients were enrolled. Of these, 33.3% and 91.8% of male and female patients were non-smokers, respectively. An increased amount of smoking (P < 0.001 for trend), fewer smoke-free years (P < 0.001 for trend), and younger age of smoking initiation (P = 0.034 for trend) were all associated with significantly lower EGFR mutation rates. Smokers had a shorter median overall survival (OS) among both EGFR-mutant and EGFR-wild type patients (17.8 vs. 21.1 months, and 7.9 vs. 11.4 months respectively; both P < 0.001). Among patients with EGFR-mutant adenocarcinoma, younger smokers were associated with shorter OS (P = 0.047). In multivariate analysis, female gender was an independent prognostic factor for OS (hazard ratio: 0.86 [95% confidence interval {CI}: 0.80-0.93]; P < 0.001 in the EGFR-mutant group and 0.88 [95% CI: 0.81-0.96]; P = 0.004 in the EGFR-wild type group).MATERIALS AND METHODS:We reviewed the National Lung Cancer database (Taiwan) to assess the impact of smoking on the EGFR mutation rate and survival in advanced lung adenocarcinoma patients during 2011 and 2014 retrospectively.CONCLUSIONS:Smoking was associated with lower incidence of EGFR mutation rate and reduced OS of advanced lung adenocarcinoma patients in a dose-dependent manner. In addition to EGFR mutation and smoking, gender also plays an important role in survival among these patients.

Background Non-small cell lung cancers (NSCLCs) frequently exhibit resistance to therapeutic drugs, which seriously hampers their treatment. Here, we set out to assess the roles of the multidrug resistance protein 1 (MRP1) and P-glycoprotein (P-gp) in the doxorubicin (DOX) resistance of NSCLC cells, as well as the putative therapeutic efficacy of MRP1 and P-gp blockers on DOX-treated NSCLC cells. Methods The impact of DOX on cell survival, DOX efflux and MRP1 and P-gp expression was assessed in 5 different NSCLC-derived cell lines (parental CH27, A549, H1299, H460, and DOX resistant CH27) in the absence or presence of MK571 (MRP1 inhibitor) or Verapamil (P-gp inhibitor), under both normoxic and hypoxic conditions. Results We found that in response to DOX treatment, NSCLC cells that express high levels of MRP1 and P-gp (such as CH27) showed a better DOX efflux and a higher DOX resistance. MK571 and Verapamil were found to abolish DOX resistance and to act as chemosensitizers for DOX therapy in all cell lines tested. We also found that hypoxia could inhibit MRP1 and P-gp expression in a HIF-1α-dependent manner, abolish DOX resistance and boost the chemosensitizer effect of MK571 and Verapamil on DOX treatment of all the NSCLC cells tested, except the DOX-resistant CH27 cells. Conclusions From our data we conclude that MRP1 and P-gp play critical roles in the DOX resistance of the NSCLC cells tested. MRP1 and P-gp targeted therapy using MK571, Verapamil, CoCl 2 or ambient hypoxia appeared to be promising in abolishing the DOX efflux and DOX resistance of the NSCLC cells. The putative therapeutic efficacies of MRP1 and/or P-gp blockers on NSCLC cells are worthy of note.

PURPOSE:Adenocarcinoma is the most dominant type of lung cancer in never-smoker patients. The risk alleles from genome-wide association studies have small odds ratios and unclear biologic roles. Here we have taken an approach featuring suitable medical actionability to identify alleles with low population frequency but high disease-causing potential.PATIENTS AND METHODS:Whole-genome sequencing was performed for a family with an unusually high density of lung adenocarcinoma with available DNA from the affected mother, four affected daughters, and one nonaffected son. Candidate risk alleles were confirmed by matrix-assisted laser desorption ionization time of flight mass spectroscopy. Validation was conducted in an external cohort of 1,135 participants without cancer and 1,312 patients with lung adenocarcinoma. Family follow-ups were performed by genotyping the relatives of the original proband and the relatives of the identified risk-allele carriers. Low-dose computed tomography scans of the chest were evaluated for lung abnormalities.RESULTS:YAP1 R331W missense mutation from the original family was identified and validated in the external controls and the cohort with lung adenocarcinoma. The YAP1 mutant-allele carrier frequency was 1.1% in patients with lung adenocarcinoma compared with 0.18% in controls (P = .0095), yielding an odds ratio (adjusted for age, sex, and smoking status) of 5.9. Among the relatives, YAP1-mutant carriers have overwhelmingly higher frequencies of developing lung adenocarcinoma or ground-glass opacity lung lesions than those who do not carry the mutation (10:0 v 1:7; P < .001). YAP1 mutation was shown to increase the colony formation ability and invasion potential of lung cancer cells.CONCLUSION:These results implicated YAP1 R331W as an allele predisposed for lung adenocarcinoma with high familial penetrance. Low-dose computed tomography scans may be recommended to this subpopulation, which is at high risk for lung cancer, for personalized prevention and health management.