Immunotherapy or Chemoimmunotherapy in Older Adults With Advanced Non-Small Cell Lung Cancer.

Importance: Immune checkpoint inhibitor (ICI) plus chemotherapy combination treatment (ICI-chemotherapy) is now a standard treatment for non-small cell lung cancer (NSCLC) without targetable oncogene alterations, but there are few data on ICI-chemotherapy for patients 75 years and older. Objective: To inform the choice of first-line drugs in clinical practice and assess the safety and efficacy of ICI-chemotherapy combination treatment in older adult patients with previously untreated advanced NSCLC. Design, Setting, and Participants: This retrospective cohort study included 58 centers in Japan. The cohort consisted of patients 75 years and older with clinical stage IIIB, IIIC, IV, postoperative or radiotherapy recurrent NSCLC. Patients started first-line systemic therapy between December 2018 and March 2021. Those receiving first-line molecular targeted drugs were excluded. The data were analyzed from February 2022 to October 2022. Exposures: Systemic therapy. Main Outcomes and Measures: The main outcomes were overall survival (OS), progression-free survival (PFS), and safety. Results: A total of 1245 patients (median [range] age, 78 [75-95] years; 967 [78%] male) with NSCLC were included in the cohort. Programmed death ligand-1 (PD-L1) expression of less than 1% occurred in 268 tumors (22%); 1% to 49% in 387 tumors (31%); 50% and higher in 410 tumors (33%), and unknown expression in 180 tumors (14%). Median OS was 20.0 (95% CI, 17.1-23.6) months for the 354 patients receiving ICI-chemotherapy (28%); 19.8 (95% CI, 16.5-23.8) months for the 425 patients receiving ICI alone (34%); 12.8 (95% CI, 10.7-15.6) months for the 311 patients receiving platinum-doublet chemotherapy (25%); and 9.5 (95% CI, 7.4-13.4) months for the 155 patients receiving single-agent chemotherapy (12%). After propensity score matching, no differences in OS and PFS were found between the patients receiving ICI-chemotherapy vs ICI alone. Each group consisted of 118 patients. For PD-L1 expression of 1% and higher the OS hazard ratio (HR) was 0.98 (95% CI, 0.67-1.42; P = .90), and the PFS HR was 0.92 (95% CI, 0.67-1.25; P = .59). Significance was also not reached when separately analyzed for lower or higher PD-L1 expression (1%-49% or ≥50%). However, grade 3 or higher immune-related adverse events occurred in 86 patients (24.3%) treated with ICI-chemotherapy and 76 (17.9%) with ICI alone (P = .03). Conclusions and Relevance: In this study, ICI-chemotherapy combination treatment did not improve survival and increased the incidence of grade 3 and higher immune-related adverse events compared with ICI alone in patients 75 years and older. Based on these results, ICI alone may be recommended for older adult patients with PD-L1-positive NSCLC.

Machine learning analysis of pathological images to predict 1-year progression-free survival of immunotherapy in patients with small-cell lung cancer.

BACKGROUND: In small-cell lung cancer (SCLC), the tumor immune microenvironment (TIME) could be a promising biomarker for immunotherapy, but objectively evaluating TIME remains challenging. Hence, we aimed to develop a predictive biomarker of immunotherapy efficacy through a machine learning analysis of the TIME. METHODS: We conducted a biomarker analysis in a prospective study of patients with extensive-stage SCLC who received chemoimmunotherapy as the first-line treatment. We trained a model to predict 1-year progression-free survival (PFS) using pathological images (H&E, programmed cell death-ligand 1 (PD-L1), and double immunohistochemical assay (cluster of differentiation 8 (CD8) and forkhead box P3 (FoxP3)) and patient information. The primary outcome was the mean area under the curve (AUC) of machine learning models in predicting the 1-year PFS. RESULTS: We analyzed 100,544 patches of pathological images from 78 patients. The mean AUC values of patient information, pathological image, and combined models were 0.789 (range 0.571-0.982), 0.782 (range 0.750-0.911), and 0.868 (range 0.786-0.929), respectively. The PFS was longer in the high efficacy group than in the low efficacy group in all three models (patient information model, HR 0.468, 95% CI 0.287 to 0.762; pathological image model, HR 0.334, 95% CI 0.117 to 0.628; combined model, HR 0.353, 95% CI 0.195 to 0.637). The machine learning analysis of the TIME had better accuracy than the human count evaluations (AUC of human count, CD8-positive lymphocyte: 0.681, FoxP3-positive lymphocytes: 0.626, PD-L1 score: 0.567). CONCLUSIONS: The spatial analysis of the TIME using machine learning predicted the immunotherapy efficacy in patients with SCLC, thus supporting its role as an immunotherapy biomarker.

Successful application of lorlatinib in a 23-year-old patient with anaplastic lymphoma kinase (ALK)-positive lung cancer and multiple brain metastases.

BACKGROUND: Anaplastic lymphoma kinase (ALK)-positive lung cancer has a better long-term prognosis with ALK-inhibitor than other lung cancers. However, resistance to ALK-inhibitors and the control of metastases in the central nervous system (CNS) remain to be a challenge in the management of ALK-positive lung cancer. CASE: We present the case of a 23-year-old man who developed multiple brain metastases while receiving alectinib treatment for ALK-positive lung cancer. After 3 months of lorlatinib initiation, brain metastases disappeared, and complete response (CR) was maintained. CONCLUSION: While lorlatinib can be used as first line therapy, this drug may be considered as second line or later option for patients with multiple brain metastases if the patient has already been treated with other ALK-inhibitors since lorlatinib is thought to have good CNS penetration. This treatment option should be verified by further research.

Durvalumab after chemoradiotherapy in non-small cell lung cancer with EGFR mutation: A real-world study (HOT2101).

Durvalumab has been administered to patients with unresectable stage III non-small cell lung cancer (NSCLC). However, it remains unclear whether durvalumab benefits these patients with epidermal growth factor receptor (EGFR) mutation. We conducted a retrospective, multicenter study of patients with EGFR mutation who received chemoradiotherapy (CRT) between June 2018 and March 2021. We assessed patient characteristics, efficacy of durvalumab, and durvalumab safety before and after targeted therapy. We collected data on a total of 673 patients, of whom 401 (59.6%) underwent EGFR mutation testing. Fifty-one patients were EGFR positive and 311 were EGFR negative. In the EGFR-positive group, there were higher proportions of females, never-smokers, and patients with adenocarcinoma histology. Of the 51 patients in the positive group and 311 in the negative group who received CRT, 45 (88.2%) and 247 (79.4%) received durvalumab, with median progression-free survival of 23.0 and 24.2 months in the positive and negative groups, respectively (hazard ratio 1.03; 95% confidence interval: 0.64-1.67). The main adverse event was pneumonitis (positive group: 62.2%; 4.4% grade 3; negative group: 62.3%; 6.9% grade 3). No treatment-related deaths were observed. Of the 45 patients in the positive group who received durvalumab, 14 (31.1%) received targeted therapy after durvalumab at the data cutoff. One patient discontinued targeted therapy after developing pneumonitis. In patients with unresectable stage III NSCLC with EGFR mutation, durvalumab after CRT is potentially safe and effective. This may be a suitable treatment sequence for these patients.

Efficacy of paclitaxel-carboplatin with bevacizumab as a late-line therapy for patients with advanced nonsquamous non-small cell lung cancer: A platinum rechallenge.

BACKGROUND: There is no well-established late-line treatment for advanced nonsquamous non-small cell lung cancer (NSCLC). Therefore, we retrospectively determined the efficacy and safety of platinum rechallenge with paclitaxel-carboplatin and bevacizumab in patients with nonsquamous NSCLC as a late-line therapy in a clinical setting. METHODS: Thirty patients with nonsquamous NSCLC who received paclitaxel-carboplatin with bevacizumab therapy as a late-line treatment at Sendai Kousei Hospital (Miyagi, Japan) between December 2011 and December 2021 were enrolled into the study. The efficacy and safety of this treatment were evaluated. The patients were further categorized into responders and nonresponders, and predictive factors of treatment response were estimated. RESULTS: The median progression-free survival (PFS) was 6.3 (range, 4.9-6.8) months, and the median overall survival (OS) was 11.8 (range, 7.2-17.2) months. There were no significant differences in PFS and OS between patients with and those without epidermal growth factor receptor mutations. In the univariate analyses of this study, responders were younger than nonresponders (p = 0.012). No fatal adverse events were reported. CONCLUSIONS: With the increase in the number of treatment options in recent years, the sequence of treatments and overall therapeutic strategy are becoming increasingly important. Thus, platinum rechallenge with paclitaxel-carboplatin and bevacizumab, a late-line treatment for patients with nonsquamous NSCLC, may be an effective therapeutic option.

Gene expression signatures as candidate biomarkers of response to PD-1 blockade in non-small cell lung cancers.

Although anti-PD-1/PD-L1 monotherapy has achieved clinical success in non-small cell lung cancer (NSCLC), definitive predictive biomarkers remain to be elucidated. In this study, we performed whole-transcriptome sequencing of pretreatment tumor tissue samples and pretreatment and on-treatment whole blood samples (WB) samples obtained from a clinically annotated cohort of NSCLC patients (n = 40) treated with nivolumab (anti-PD-1) monotherapy. Using a single-sample gene set enrichment scoring method, we found that the tumors of responders with lung adenocarcinoma (LUAD, n = 20) are inherently immunogenic to promote antitumor immunity, whereas those with lung squamous cell carcinoma (LUSC, n = 18) have a less immunosuppressive tumor microenvironment. These findings suggested that nivolumab may function as a molecular targeted agent in LUAD and as an immunomodulating agent in LUSC. In addition, our study explains why the reliability of PD-L1 expression on tumor cells as a predictive biomarker for the response to nivolumab monotherapy is quite different between LUAD and LUSC.

Association of immune-related pneumonitis with clinical benefit of anti-programmed cell death-1 monotherapy in advanced non-small cell lung cancer.

BACKGROUND: The association between the development of checkpoint inhibitor pneumonitis (CIP) with tumor response and survival has remained unclear so far. The aim of the present study was to evaluate the association between CIP and the clinical efficacy of anti-programmed cell death-1 antibody in patients with advanced non-small cell lung cancer (NSCLC). METHODS: Between January 2016 and August 2019, 203 advanced NSCLC patients were administered with nivolumab or pembrolizumab. Comparisons were made between patients with and without CIP. We evaluated the time-to-treatment failure (TTF), progression-free survival (PFS), and overall survival (OS). RESULTS: CIP was observed in 28 (14%) patients. CIP was associated with a longer PFS (18.9 months [95% confidence interval, CI: 8.7 months-not reached] vs. 3.9 months [95% CI: 3.4-5.1 months, p < 0.01]) and longer OS (27.4 [95% CI: 20.7 months-not reached] vs. 14.8 months [95% CI: 11.2-17.9 months, p = 0.003]). Most patients discontinued the immune checkpoint inhibitor (ICI) treatment when they developed CIP. Seven patients (25%) lived for more than 300 days from treatment discontinuation and did not show any long-term tumor growth after treatment discontinuation. CONCLUSION: CIP was associated with prolonged PFS and OS. Additionally, 25% of CIP patients did not show any tumor growth for long periods after treatment discontinuation. Careful management of CIP can help in obtaining the best clinical efficacy from anti-PD-1 antibody.

Pharmacokinetics of edoxaban in EGFR-mutated non-small cell lung cancer patients with venous thromboembolism.

BACKGROUND: The risk of venous thromboembolism (VTE) is increased 7-fold in patients with cancer than in those without. Low-molecular-weight heparin is the standard treatment for cancer-associated VTE. Direct oral anticoagulants (DOACs) are not inferior to low-molecular-weight heparin with respect to the general outcome of recurrent VTE. Warfarin is associated with a risk of bleeding when used in combination with gefitinib or erlotinib which are epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs). It is unclear, however, whether combination treatments with EGFR-TKIs and DOACs pose the same risk. We aimed to identify anticancer drugs and anticoagulants that can be used safely in combination, as accompanying research to an observational study on VTE incidence rates in lung cancer patients (Rising-VTE/NEJ037 study). METHODS: Twelve patients receiving EFGR-TKI monotherapy and VTE treatment were enrolled. Blood samples were collected in time series after the first dose of edoxaban, and further samples were collected within 8-15 days after administering EGFR-TKIs. The pharmacokinetics (PK) of edoxaban were analyzed using a non-compartmental model. RESULTS: Edoxaban concentrations (30 mg once daily) were measured in eight patients. PK analyses showed no significant differences before and after co-administration of EGFR-TKIs (gefitinib, erlotinib, and afatinib). CONCLUSIONS: Our findings indicate that the PK of edoxaban was not considerably affected by co-administration of EGFR-TKIs (gefitinib, erlotinib, and afatinib).

Relationship between Programmed Cell Death Protein Ligand 1 Expression and Immune-related Adverse Events in Non-small-cell Lung Cancer Patients Treated with Pembrolizumab.

INTRODUCTION: Immune checkpoint inhibitors (ICIs) can lead to immune-related adverse events (irAEs). A correlation between the development of irAEs and efficacy has been suggested; however, it is unclear whether there is a relationship between programmed death ligand 1 (PD-L1) expression and the development of these events. METHODS: We performed a retrospective study of advanced or metastatic non-small cell lung cancer (NSCLC) patients who were treated with pembrolizumab monotherapy at our institution between May 2015 and April 2018 (n = 44). Patients were categorized into two groups, specifically those with irAEs (irAE group) or without (non-irAE group), and we evaluated the objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS). Predictors of irAEs were examined by multivariate analysis. RESULTS: irAEs of any grade occurred in 31 (70.5%) patients. The median PFS was 10.9 months in the irAE group versus 3.7 months in the non-irAE group (P < 0.001). ORR and DCR were also higher in the irAE group than in the non-irAE group. Furthermore, high PD-L1 expression (≥50%) was a predictive factor of irAE based on logistic regression (P = 0.004). CONCLUSIONS: In patients with advanced NSCLC treated with pembrolizumab monotherapy, ORR, DCR, and PFS were significantly better in the irAE group than in the non-irAE group. High PD-L1 expression, at the time of pretreatment, was identified as an independent predictor of irAE development. We believe that more careful management of irAEs for individuals with high PD-L1 expression is needed to improve clinical benefits. Further, PD-L1 expression might be useful for ICI risk management.

Correction to: Outcomes associated with immune-related adverse events in metastatic non-small cell lung cancer treated with nivolumab: a pooled exploratory analysis from a global cohort.

The original version of this article unfortunately contained a mistake. The second sentence of the section "irAEs and ICI efficacy" should read as.

Outcomes associated with immune-related adverse events in metastatic non-small cell lung cancer treated with nivolumab: a pooled exploratory analysis from a global cohort.

BACKGROUND: Immune-related adverse events (irAEs) comprise a distinct spectrum of auto-inflammatory manifestations triggered due to immune checkpoint inhibitors (ICI). Current data on the association of irAEs with outcomes in NSCLC treated with nivolumab are limited. METHODS AND OBJECTIVES: We pooled data from 531 metastatic NSCLC patients from five centers treated with nivolumab after failing platinum-based chemotherapy. The primary objective was to investigate the relationship between irAEs with clinical benefit to nivolumab as well as to elucidate patterns of irAE-related ICI discontinuations and their impact on survival. RESULTS: 33.0% (173/531) of patients treated with nivolumab were noted to have an irAE. Patients with irAEs had a significantly longer median PFS [6.1 vs. 3.1 months, HR 0.68 95% CI (0.55-0.85); p = 0.001] and OS [14.9 vs. 7.4 months, HR 0.66 95% CI (0.52-0.82); p < 0.001)] compared to those without irAEs. In multivariate analysis, the presence of irAEs showed a significantly better PFS [HR 0.69, 95% CI (0.55-0.87); p = 0.002] and a trend for better OS [HR 0.62, 95% CI (0.55-1.03); p = 0.057]. Patients with permanent ICI discontinuation secondary to index irAE had a significantly shorter median PFS [2.3 vs. 6.6 months, HR 1.74 95% CI (1.06-2.80); p = 0.02] and median OS [3.6 vs. 17.6 months; HR 2.61 95% CI (1.61-4.21); p < 0.001] compared to those that did not have permanent ICI discontinuation. CONCLUSIONS: Our pooled exploratory analysis demonstrates improved clinical benefit to nivolumab in NSCLC patients experiencing irAEs. We also observed negative impact of irAE-related treatment discontinuation on survival in this group of patients.

Association Between Skin Reaction and Clinical Benefit in Patients Treated with Anti-Programmed Cell Death 1 Monotherapy for Advanced Non-Small Cell Lung Cancer.

BACKGROUND: Anti-programmed cell death 1 antibody is a standard therapy for advanced non-small cell lung cancer (NSCLC). However, immune-related adverse events (irAEs), such as skin reactions, are frequently observed. Although skin reactions are associated with clinical efficacy in melanoma, this association in advanced NSCLC and predictors of irAEs remain unclear. Accordingly, this study identified potential correlations of skin reactions with clinical efficacy and clinical predictors of development of skin reactions. SUBJECTS, MATERIALS, AND METHODS: We retrospectively surveyed patients with advanced NSCLC who received nivolumab or pembrolizumab monotherapy at Sendai Kousei Hospital (n = 155) during January 2016 to April 2018. Treatment efficacy was evaluated in patients with and without skin reactions, and associated predictive markers were determined. A 6-week landmark analysis was conducted to assess the clinical benefit of early skin reactions. RESULTS: Skin reactions were observed in 51 patients with a median time to onset of 6.4 weeks. The overall response rate (ORR) was significantly higher in patients with skin reactions (57% vs. 19%, p < .001). Median progression-free survival (PFS) durations of 12.9 and 3.5 months and overall survival durations of not reached and 11.4 months were observed in patients with and without skin reactions, respectively. In the 6-week landmark analysis, the ORR was significantly higher in patients with skin reactions, and skin reactions were significantly associated with increased PFS. A multivariate analysis identified pre-existing rheumatoid factor (RF) as an independent predictor of skin reactions. CONCLUSION: Skin reactions appeared beneficial in patients treated with nivolumab/pembrolizumab for advanced NSCLC and could be predicted by pre-existing RF. Further large-scale validations studies are warranted. IMPLICATIONS FOR PRACTICE: This single-institutional medical record review that included 155 patients with advanced non-small cell lung cancer who were treated with nivolumab or pembrolizumab monotherapy revealed that overall response rate and progression-free survival were significantly better in patients with skin reactions. Pre-existing rheumatoid factor was an independent predictor of skin reactions.

Association of low body surface area with dose reduction and/or discontinuation of nintedanib in patients with idiopathic pulmonary fibrosis: a pilot study.

BACKGROUND: We have often encountered adverse events requiring dose reduction and/or discontinuation of nintedanib in patients with idiopathic pulmonary fibrosis. OBJECTIVES: The objectives of this study were to clarify the incidence of dose reduction and/or discontinuation following the commercialization of nintedanib and to investigate predictors of dose reduction and/or discontinuation of nintedanib at our hospital. METHODS: We retrospectively identified 25 patients who had received nintedanib 150 mg twice daily at Sendai Kousei Hospital and categorized them into two groups according to whether they had or had not required dose reduction and/or discontinuation and sought to identify predictors of dose reduction and/or discontinuation. RESULTS: Seventeen patients developed adverse events, which included diarrhea (n=10, 44%), hepatotoxicity (n=7, 28%), and anorexia (n=2, 16%). No adverse event-related deaths occurred during the study period. Patients who required dose reduction and/or discontinuation were significantly older than those who did not (72 years vs 67 years; P=0.047). Body surface area (BSA) was significantly lower in the group that needed dose reduction and/or discontinuation than in the group that did not (1.63 m2 vs. 1.78 m2; P=0.028). Multivariate logistic regression revealed that the association of low BSA with dose reduction and/or discontinuation was statistically significant. CONCLUSIONS: A low BSA was associated with dose reduction and/or discontinuation of nintedanib in patients with idiopathic pulmonary fibrosis. Further studies in larger patient samples are needed to validate these findings.

Profiling Preexisting Antibodies in Patients Treated With Anti-PD-1 Therapy for Advanced Non-Small Cell Lung Cancer.

Importance: Administration of anti-programmed cell death protein 1 (anti-PD-1) is now standard therapy in advanced non-small cell lung cancer (NSCLC). However, immune checkpoint inhibitors, including anti-PD-1, have not been assessed in patients with subclinical disease with advanced NSCLC, and no useful clinical biomarkers have been associated with immune-related adverse events (irAEs) among these patients treated with anti-PD-1. Objective: To assess the safety and efficacy of anti-PD-1 treatment in patients with subclinical disease with advanced NSCLC and with or without preexisting autoimmune markers, including rheumatoid factor, antinuclear antibody, antithyroglobulin, and antithyroid peroxidase; and to assess potential clinical biomarkers that may be meaningfully and conveniently associated with clinical benefit or with irAEs following anti-PD-1 treatment. Design, Setting, and Participants: This medical records analysis retrospectively evaluated 137 patients who received nivolumab or pembrolizumab monotherapy at Sendai Kousei Hospital in Japan between January 2016 and January 2018. Treatment efficacy and irAEs were evaluated along with candidate factors that may be associated with irAEs. Exposures: Absence or presence of specific autoimmune markers and antibodies before treatment. Main Outcomes and Measures: Preexisting antibodies and autoimmune markers, progression-free survival (PFS), and irAEs. Results: Of 137 patients with advanced NSCLC, 105 were men, the median age was 68 (range, 36-88) years, 99 underwent nivolumab monotherapy, 38 underwent pembrolizumab monotherapy, and 134 had an Eastern Cooperative Oncology Group performance status of 0 or 1. The median PFS was 6.5 (95% CI, 4.4-12.9) months among patients with examined preexisting antibodies and 3.5 (95% CI, 2.4-4.1) months among patients without, suggesting significantly better prognosis in the former. The hazard ratio for disease progression or death in the presence of the examined preexisting antibodies was 0.53 (95% CI, 0.36-0.79; P = .002). The PFS was significantly longer among patients with any preexisting antibodies than among those without. The examined preexisting antibodies (48 patients [73%]) and rheumatoid factor (26 patients [39%]) were more common among patients who developed irAEs. Multivariate analysis indicated that the presence of the examined preexisting antibodies was independently associated with irAEs (odds ratio, 3.25; 95% CI, 1.59-6.65; P = .001). Skin reactions were more frequent among patients with preexisting rheumatoid factor (47% vs 24%, P = .02), whereas thyroid dysfunction was more frequent among patients with preexisting antithyroid antibodies (20% vs 1%, P < .001). Conclusions and Relevance: The presence of the examined preexisting antibodies was associated with clinical benefit and with the development of irAEs in patients with NSCLC treated with nivolumab or pembrolizumab. Thus, the presence of these autoimmune markers may help determine the risk-benefit ratio for individual patients with NSCLC, maximizing therapeutic benefits while minimizing irAEs.

Association of Immune-Related Adverse Events with Clinical Benefit in Patients with Advanced Non-Small-Cell Lung Cancer Treated with Nivolumab.

BACKGROUND: Immune-related adverse events (irAEs) are frequently observed with nivolumab monotherapy. This study aimed to evaluate whether the development of irAEs correlates with treatment response in advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: We conducted a retrospective study of patients who received nivolumab monotherapy at Sendai Kousei Hospital (n = 70). The patients were categorized into two groups based on the incidence of irAEs: those with irAEs (irAE group) or those without (non-irAE group). Treatment efficacy was evaluated in each group. The patients were further categorized into responders and nonresponders, and predictive factors of treatment response were determined. RESULTS: The objective response rate was 57% in the irAE group versus 12% in the non-irAE group. Median progression-free survival was 12.0 months in the irAE versus 3.6 months in the non-irAE group. The incidence of both irAEs and pre-existing antithyroid antibody was significantly higher in responders than in nonresponders. Multivariate analysis identified incidence of irAEs and pre-existing antithyroid antibody as an independent predictor of treatment response. CONCLUSION: Objective response rate and progression-free survival were significantly better in the irAE than in the non-irAE group in patients with advanced NSCLC treated with nivolumab monotherapy. The development of irAEs was associated with clinical efficacy, and the presence of pre-existing antithyroid antibody might be correlated with treatment response to nivolumab monotherapy. IMPLICATIONS FOR PRACTICE: Immune-related adverse events (irAEs) are frequently observed with nivolumab monotherapy. This study evaluted whether the development of irAEs correlates with treatment response in advanced non-small-cell lung cancer. Results showed that the objective response rate and progression-free survival were significantly better in the patients who developed irAEs than in the patients who did not develop irAEs, and the incidence of irAEs and positivity for antithyroid antibody at pretreatment were independent predictors of treatment response of nivolumab monotherapy. Therefore, the development of irAEs predicts clinical benefit and suggests that cautious management of irAEs can lead to achieving maximum clinical benefit from nivolumab monotherapy.

Array-based genome-wide RNAi screening to identify shRNAs that enhance p53-related apoptosis in human cancer cells.

p53 transduction is a potentially effective cancer therapy but does not result in a good therapeutic response in all human cancers due to resistance to apoptosis. To discover factors that overcome resistance to p53-induced apoptosis, we attempted to identify RNAi sequences that enhance p53-induced apoptosis. We screened a genome-wide lentiviral shRNA library in liver cancer Huh-7 and pancreatic cancer Panc-1 cells, both of which resist p53-induced apoptosis. After the infection of adenovirus expressing p53 or LacZ as a control, shRNA-treated populations were analyzed by microarray. We identified shRNAs that were significantly decreased in p53-infected cells compared with control cells. Among these shRNAs, shRNA-58335 was markedly decreased in both cancer cell lines tested. shRNA-58335 enhanced p53-related apoptosis in vitro and augmented the inhibitory effect of adenoviral p53 transduction on tumor growth in vivo. Furthermore, the enhanced apoptotic response by shRNA-58335 was also confirmed by treatment with PRIMA-1, which reactivates mutant p53, instead of adenoviral p53 transduction. We found that shRNA-58335 evokes the apoptotic response following p53 transduction or functional restoration of p53 with a small molecule drug in cancer cells resistant to p53-induced apoptosis. The combination of p53 restoration and RNAi-based drugs is expected to be a promising novel cancer therapy.

CLCA2, a target of the p53 family, negatively regulates cancer cell migration and invasion.

The tumor suppressor p53 transcriptionally regulates a number of genes that are involved in cell-cycle inhibition, apoptosis and the maintenance of genetic stability. Recent studies suggest that p53 also contributes to the regulation of cell migration and invasion. Here, we show that human chloride channel accessory-2 (CLCA2) is a target gene of the p53 family (p53, p73 and p63). CLCA2 is induced by DNA damage in a p53-dependent manner. The p53 family proteins activate the CLCA2 promoter by binding directly to the conserved consensus p53-binding site present in the CLCA2 promoter. In terms of function, ectopic expression of CLCA2 inhibited cancer cell migration. In contrast, silencing CLCA2 with siRNA stimulated cancer cell migration and invasion. We also found that inactivation of CLCA2 enhanced the expression of focal adhesion kinase (FAK), as well as its promoter activation. A small-molecule FAK inhibitor reduced the effect of CLCA2 siRNA on cell migration and invasion, suggesting that CLCA2 inhibits cancer cell migration and invasion through suppression of the FAK signaling pathway. Furthermore, there was an inverse correlation between CLCA2 and FAK expression in 251 human breast cancer tissues. These results strongly suggest that CLCA2 is involved in the p53 tumor suppressor network and has a significant effect on cell migration and invasion.