Preventive effect of tertiary lymphoid structures on lymph node metastasis of lung adenocarcinoma.

BACKGROUND: Ectopic lymphoid formations are called tertiary lymphoid structures (TLSs). TLSs in cancer have been reported to be associated with good prognosis and immunotherapy response. However, the relationship between TLSs and lymph node (LN) metastasis is unclear. METHODS: We analyzed 218 patients with radically resected lung adenocarcinoma. TLSs were defined as the overlap of T cell zone and B cell zone. Granzyme B + cells were defined as cytotoxic lymphocytes. We evaluated phenotypes of lymphocytes in TLSs, tumor-infiltrating lymphocytes (TILs) and LNs by immunohistochemistry. We divided the patients into mature TLS (DC-Lamp high) and immature TLS (DC-Lamp low) groups. The relationship between TLS maturation and clinicopathological factors was analyzed. RESULTS: The mature TLS group was associated with significantly lower frequency of LN metastasis (P < 0.0001) and early cancer stage (P = 0.0049). The mature TLS group had significantly more CD8 + (P = 0.0203) and Foxp3 + (P = 0.0141) cells in TILs than the immature TLS group had. Mature TLSs were independently associated with a favorable overall survival (hazard ratio [HR] = 0.17, P = 0.0220) and disease-free survival (HR = 0.54, P = 0.0436). Multivariate analysis showed that mature TLS was an independent low-risk factor for LN metastasis (odds ratio = 0.06, P = 0.0003). The number of cytotoxic lymphocytes in LNs was higher in the mature TLS group than in the immature group (20.0 vs. 15.1, P = 0.017). CONCLUSION: Mature TLSs were associated with an increased number of cytotoxic lymphocytes in draining LNs, a lower frequency of LN metastasis, and favorable outcomes. Mature TLSs may support antitumor immunity by lymphocyte activation.

Smoking enhances the expression of angiotensin-converting enzyme 2 involved in the efficiency of severe acute respiratory syndrome coronavirus 2 infection.

Smoking is one of the risk factors most closely related to the severity of coronavirus disease 2019 (COVID-19). However, the relationship between smoking history and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity is unknown. In this study, we evaluated the ACE2 expression level in the lungs of current smokers, ex-smokers, and nonsmokers. The ACE2 expression level of ex-smokers who smoked cigarettes until recently (cessation period shorter than 6 months) was higher than that of nonsmokers and ex-smokers with a long history of nonsmoking (cessation period longer than 6 months). We also showed that the efficiency of SARS-CoV-2 infection was enhanced in a manner dependent on the angiotensin-converting enzyme 2 (ACE2) expression level. Using RNA-seq analysis on the lungs of smokers, we identified that the expression of inflammatory signaling genes was correlated with ACE2 expression. Notably, with increasing duration of smoking cessation among ex-smokers, not only ACE2 expression level but also the expression levels of inflammatory signaling genes decreased. These results indicated that smoking enhances the expression levels of ACE2 and inflammatory signaling genes. Our data suggest that the efficiency of SARS-CoV-2 infection is enhanced by smoking-mediated upregulation of ACE2 expression level.

Thrombus formation at the stump of the pulmonary vein after lobectomy: a prospective multi-institutional study.

PURPOSE: Recent reports suggest that postoperative cerebral infarction following lung cancer surgery is caused by thrombus formation at the stump of the pulmonary vein and that the risk is highest after left upper lobectomy (LUL). Thrombosis at the stump of the pulmonary vein and the incidence of cerebral infarction was investigated prospectively in patients who underwent lobectomy for lung cancer. METHODS: Lung cancer patients undergoing planned pulmonary lobectomy were enrolled. The endpoint was to confirm if there is a higher incidence of thrombus formation (primary) and a higher incidence of cerebral infarction (secondary) in patients undergoing LUL. We planned to accrue 600 patients. An interim analysis was scheduled for just after the data center received the final clinical review form of the 300th patient. RESULTS: The interim analysis revealed a significant difference in the primary endpoint. In the final analysis, thrombus was identified in 16 of 88 LUL patients (20.5%), and in 4 of 247 patients who underwent other types of lobectomy (1.6%) (p < 0.05). Cerebral infarction was identified in 1 of the LUL patients (1.3%) and in 9 of the other patients (3.6%) (p = 0.318). CONCLUSIONS: Thrombus frequently forms at the stump of the left superior pulmonary vein after LUL. However, our study did not identify a relationship between thrombosis and cerebral infarction.

A propensity score-matched analysis of the impact of statin therapy on the outcomes of patients with non-small-cell lung cancer receiving anti-PD-1 monotherapy: a multicenter retrospective study.

BACKGROUND: Many studies have recently reported the association of concomitant medications with the response and survival in patients with non-small-cell lung cancer (NSCLC) treated with cancer immunotherapy. However, the clinical impact of statin therapy on the outcome of cancer immunotherapy in patients with NSCLC is poorly understood. METHODS: In our database, we retrospectively identified and enrolled 390 patients with advanced or recurrent NSCLC who were treated with anti-programmed cell death-1 (PD-1) monotherapy in clinical practice between January 2016 and December 2019 at 3 medical centers in Japan to examine the clinical impact of statin therapy on the survival of patients with NSCLC receiving anti-PD-1 monotherapy. A propensity score-matched analysis was conducted to minimize the bias arising from the patients' backgrounds. RESULTS: The Kaplan-Meier curves of the propensity score-matched cohort showed that the overall survival (OS), but not the progression-free survival (PFS), was significantly longer in patients receiving statin therapy. However, a Cox regression analysis in the propensity score-matched cohort revealed that statin therapy was not an independent favorable prognostic factor, although it tended to be correlated with a favorable outcome. CONCLUSIONS: Statin therapy may be a combination tool for cancer immunotherapy in patients with NSCLC. These findings should be validated in further prospective studies with larger sample sizes.

Clinical impact of probiotics on the efficacy of anti-PD-1 monotherapy in patients with nonsmall cell lung cancer: A multicenter retrospective survival analysis study with inverse probability of treatment weighting.

The gastrointestinal microbiota was reported as an important factor for the response to cancer immunotherapy. Probiotics associated with gastrointestinal dysbiosis and bacterial richness may affect the efficacy of cancer immunotherapy drugs. However, the clinical impact of probiotics on the efficacy of cancer immunotherapy in patients with nonsmall cell lung cancer (NSCLC) is poorly understood. The outcomes of 294 patients with advanced or recurrent NSCLC who received antiprogrammed cell death-1 (PD-1) therapy (nivolumab or pembrolizumab monotherapy) at three medical centers in Japan were analyzed in our study. We used inverse probability of treatment weighting (IPTW) to minimize the bias arising from the patients' backgrounds. The IPTW-adjusted Kaplan-Meier curves showed that progression-free survival (nonuse vs use: hazard ratio [HR] [95% confidence interval {CI}] = 1.73 [1.42-2.11], log-rank test P = .0229), but not overall survival (nonuse vs use: HR [95%CI] = 1.40 [1.13-1.74], log-rank test P = .1835), was significantly longer in patients who received probiotics. Moreover, the IPTW-adjusted univariate analyses showed that nonuse or use of probiotics was significantly associated with disease control (nonuse vs use: odds ratio [OR] [95%CI] = 0.51 [0.35-0.74], P = .0004) and overall response (nonuse vs use: OR [95%CI] = 0.43 [0.29-0.63], P < .0001). In this multicenter and retrospective study, probiotics use was associated with favorable clinical outcomes in patients with advanced or recurrent NSCLC who received anti-PD-1 monotherapy. The findings should be validated in a future prospective study.

Identification of SLC38A7 as a Prognostic Marker and Potential Therapeutic Target of Lung Squamous Cell Carcinoma.

BACKGROUND: No effective molecular targeted therapy has been established for SCC. We conducted a comprehensive study of SCC patients using RNA-sequencing and TCGA dataset to clarify the driver oncogene of SCC. METHOD: Forty-six samples of 23 patients were totally analyzed with RNA-sequencing. We then searched for candidate-oncogenes of SCC using the TCGA database. To identify candidate oncogenes, we used the following 2 criteria: (1) the genes of interest were overexpressed in tumor tissues of SCC patients in comparison to normal tissues; and (2) using an integrated mRNA expression and DNA copy number profiling analysis using the TCGA dataset, the DNA copy number of the genes was positively correlated with the mRNA expression. RESULT: We identified 188 candidate-oncogenes. Among those, the high expression of SLC38A7 was a strong prognostic marker that was significantly associated with a poor prognosis in terms of both overall survival (OS) and recurrence-free survival in the TCGA dataset (P < 0.05). Additionally, 202 resected SCC specimens were also subjected to an immunohistochemical analysis. Patients with the high expression of SLC38A7 (alternative name is sodium-coupled amino acid transporters 7) protein showed significantly shorter OS in comparison to those with the low expression of SLC38A7 protein [median OS 3.9 years (95% confidence interval, 2.4-6.4 years) vs 2.2 years (95% confidence interval, 1.9-4.1 years); log rank test: P = 0.0021]. CONCLUSION: SLC38A7, which is the primary lysosomal glutamine transporter required for the extracellular protein-dependent growth of cancer cells, was identified as a candidate therapeutic target of SCC.

Prognostic impact of primary cancer adjoining emphysematous bullae in non-small cell lung cancer patients treated with immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have become a standard therapy in non-small cell lung cancer (NSCLC). Although lung cancer adjoining emphysematous bullae (Ca-ADJ) were reported to express higher programmed cell death-ligand 1 (PD-L1), the predictive impact of Ca-ADJ on the response to ICIs is unknown. METHODS: Two hundred and fifty-seven advanced or recurrent NSCLC patients treated with ICI monotherapy at Kyushu University Hospital and National Hospital Organization Kyushu Cancer Center were analyzed. To minimize the bias arising from the patients' background, adjusted Kaplan-Meier survival curves and Cox proportional hazards regression analyses using inverse probability of treatment weights (IPTW) were performed. RESULTS: Of the 257 patients, 55 had Ca-ADJ. Patients with Ca-ADJ were significantly associated with younger age (P = 0.0343), male sex (P = 0.0070), and smoking (P = 0.0080). The objective response rate of cases with Ca-ADJ was significantly higher than that of those without Ca-ADJ (36.4% vs. 20.8%, respectively; P = 0.0167). The disease control rate of cases with Ca-ADJ was also significantly higher than tumors without Ca-ADJ (63.6% vs. 47.5%, respectively; P = 0.0341). The IPTW-adjusted Kaplan-Meier curves showed that patients with Ca-ADJ had significantly longer progression-free survival (PFS) and overall survival (OS) than those without Ca-ADJ (P = 0.0407 and P = 0.0126, respectively). On IPTW-adjusted Cox analysis, Ca-ADJ was an independent predictor of PFS and OS (P < 0.0001 and P < 0.0001, respectively). CONCLUSIONS: Patients with Ca-ADJ may be good candidates for ICIs. These findings should be validated prospectively.

Interleukin-38 promotes tumor growth through regulation of CD8+ tumor-infiltrating lymphocytes in lung cancer tumor microenvironment.

BACKGROUND: Interleukin (IL)-38 was discovered in 2001 and is a member of the IL-1 family of cytokines. IL-38 shows anti-inflammatory activity in several inflammatory diseases. In lung adenocarcinoma, we previously demonstrated that high IL-38 expression in tumor cells was associated with poor prognosis. However, the role of IL-38 in the tumor microenvironment has not been clarified. METHODS: IL-38-plasmid-transfected Lewis lung carcinoma cells (LLC-IL38) and empty vector-transfected LLC cells (LLC-vector) were established. Cell proliferation in vitro and tumor growth in vivo were examined, and immunohistochemical staining was used to assess tumor-infiltrating lymphocytes (TILs). A CD8+ lymphocyte depletion model was established to show the association between IL-38 and CD8+ lymphocytes. Moreover, we examined the association between IL-38 expression and CD8+ TILs in human samples, analyzing immunohistochemical staining in 226 patients with radically resected lung adenocarcinoma. RESULTS: Tumor growth of LLC-IL38 in vivo was significantly increased compared with that of LLC-vector, although cell proliferation of LLC-IL38 in vitro was lower than that of LLC-vector. CD8+ TILs were significantly decreased in LLC-IL38 tumor compared with LLC-vector tumor. The difference in tumor growth between LLC-IL38 and LLC-vector became insignificant after depletion of CD8+ lymphocytes. In immunohistochemical staining in tissues from patients with lung adenocarcinoma, multivariate analysis showed high IL-38 expression was an independent negative predicter of high density of CD8+ TILs. CONCLUSION: We demonstrated that high IL-38 expression in tumor cells was significantly associated with reduction of CD8+ TILs and tumor progression. These results suggest that IL-38 could be a therapeutic target for lung cancer.

Prognostic Impact of Smoking Period in Patients with Surgically Resected Non-small Cell Lung Cancer.

BACKGROUND: The pack-year index, which is calculated by multiplying a smoking period by the number of cigarette packs smoked per day, is frequently used to investigate the risk of developing lung cancer. Notably, however, whether the smoking period or the number of packs per day is more predictive of postoperative prognosis remains unclear in non-small cell lung cancer (NSCLC) patients who receive curative lung resection. PATIENTS AND METHODS: Initial screening included 2055 consecutive lung cancer patients who had underwent curative lung resection between 2000 and 2016 at a single center in Japan. Data from 1134 NSCLC patients with smoking history were ultimately analyzed. Time-dependent areas under the curve (AUCs) were used to compare diagnostic accuracy. RESULTS: On univariate analysis, the number of packs smoked per day was not a significant predictor of disease-free survival (DFS; p = 0.2387) or overall survival (OS; p = 0.1357). On multivariable analysis, smoking period was an independent predictor of DFS and OS (both p < 0.0001). Time-dependent smoking period AUCs were superior to those of number of packs smoked per day. On subgroup analyses, patients with a smoking period ≥ 40 years had significantly shorter DFS and OS than those with a smoking period of < 40 years, independent of sex, clinical stage, and histological type. CONCLUSIONS: Smoking period was a significant prognostic indicator in NSCLC patients who underwent curative lung resection, which should be validated in further prospective and/or multicenter studies with large sample sizes.

Predictive and prognostic impact of primary tumor-bearing lobe in nonsmall cell lung cancer patients treated with anti-PD-1 therapy.

Immunotherapy targeting programmed cell death-1 (PD-1) has become a standard pharmacological therapy. Although tumor mutation burden level was reported to depend on the tumor location in nonsmall cell lung cancer (NSCLC), predictive impact of the tumor location on the response to anti-PD-1 therapy is unknown. Two hundred and seventeen advanced or recurrent NSCLC patients treated with anti-PD-1 therapy at Kyushu University Hospital and National Hospital Organization Kyushu Cancer Center were analyzed. To minimize the bias arising from the patients' background, adjusted Kaplan-Meier survival curves and Cox proportional hazards regression analyses using inverse probability of treatment weights (IPTW) were performed. Of the 217 patients, 132, 27, and 58 had primary NSCLC in upper, middle, and lower lobes, respectively. Patients with NSCLC in upper lobe were significantly associated with younger age (P = .0070) and smoker (P = .0003). The epidermal growth factor receptor-wild type and tumor location in upper lobe were independent predictors of disease control (P = .0175 and P = .0425, respectively). The IPTW-adjusted Kaplan-Meier curves showed that patients with NSCLC in the upper lobes had significantly longer progression-free survival (PFS) and overall survival (OS) than those in middle/lower lobes (P = .0026 and P = .0015, respectively). On IPTW adjusted Cox analysis, NSCLC in the upper lobe was an independent predictor of PFS and OS (P = .0078 and P = .0034, respectively). Patients with primary NSCLC in the upper lobes may be good candidates for anti-PD-1 therapy. These findings should be validated prospectively.

Paired genetic analysis by next-generation sequencing of lung cancer and associated idiopathic pulmonary fibrosis.

The pathogenesis of lung cancer associated with idiopathic pulmonary fibrosis (IPF) has remained largely uncharacterized. To provide insight into this condition, we undertook genomic profiling of IPF-associated lung cancer as well as of adjacent fibrosing lung tissue in surgical specimens. Isolated DNA and RNA from 17 IPF-associated non-small cell lung cancer and 15 paired fibrosing lung tissue specimens were analyzed by next-generation sequencing with a panel that targets 161 cancer-related genes. Somatic genetic alterations were frequently identified in TP53 (n = 6, 35.3%) and PIK3CA (n = 5, 29.4%) genes in tumor samples as well as in EGFR (n = 7, 46.7%), PIK3CA (n = 5, 33.3%), ERBB3 (n = 4, 26.7%), and KDR (n = 4, 26.7%) in IPF samples. Genes related to the RAS-RAF signaling pathway were also frequently altered in tumor (n = 7, 41.2%) and IPF (n = 3, 20.0%) samples. The number of somatic alterations identified in IPF samples was almost as large as that detected in paired tumor samples (81 vs 90, respectively). However, only 6 of the 81 somatic alterations detected in IPF samples overlapped with those in paired tumor samples. The accumulation of somatic mutations was thus apparent in IPF tissue of patients with IPF-associated lung cancer, and the RAS-RAF pathway was implicated in lung tumorigenesis. The finding that somatic alterations were not frequently shared between tumor and corresponding IPF tissue indicates that IPF-associated lung cancer does not develop through the stepwise accumulation of somatic alterations in IPF.

Combined Evaluation of Tumor-Infiltrating CD8 + and FoxP3 + Lymphocytes Provides Accurate Prognosis in Stage IA Lung Adenocarcinoma.

BACKGROUND: Immunotherapy has become a standard treatment option for non-small cell lung cancer (NSCLC), with the tumor microenvironment attracting significant attention. CD8 + and forkhead box protein P3 + (FoxP3 +) tumor-infiltrating lymphocytes (TILs) influence the tumor microenvironment, but the clinical significance of CD8 + and FoxP3 + TILs in stage IA lung adenocarcinoma (LAD) is poorly understood. METHODS: We analyzed 203 patients with stage IA primary LAD who had undergone surgery at Kyushu University from January 2003 to December 2012. We evaluated CD8 + and FoxP3 + TILs by immunohistochemistry. We set the cutoff values at 50 cells/0.04 mm2 for CD8 + TILs and 20 cells/0.04 mm2 for FoxP3 + TILs, respectively. We divided the patients into four groups: CD8-Low/FoxP3-Low; CD8-High/FoxP3-Low; CD8-Low/FoxP3-High; and CD8-High/FoxP3-High. We compared clinical outcomes among them. Programmed cell death ligand-1 (PD-L1) expression by tumor cells was also evaluated as previously reported. RESULTS: Respectively, 104 (51.2%), 46 (22.7%), 22 (10.8%), and 31 (15.3%) patients were classified as CD8-Low/FoxP3-Low, CD8-High/FoxP3-Low, CD8-Low/FoxP3-High, and CD8-High/FoxP3-High. Both disease-free survival (DFS) and overall survival (OS) were significantly worse in the CD8-Low/FoxP3-High group than the other groups (5-year DFS: 66.3% vs. 90.5%; P = 0.0007, 5-year OS: 90.9% vs. 97.0%; P = 0.0077). In the multivariate analysis, CD8-Low/FoxP3-High and PD-L1 expression were independent prognostic factors of DFS, and lymphatic invasion, surgical procedure, and PD-L1 expression were independent prognostic factors of OS. CONCLUSIONS: CD8-Low/FoxP3-High was an independent prognostic factor of DFS (hazard ratio: 3.22; 95% confidence interval: 1.321-7.179; P = 0.0121) in stage IA LAD. Immunosuppressive conditions were associated with poor prognosis in stage IA LAD.

The Significance of CD44 Variant 9 in Resected Lung Adenocarcinoma: Correlation with Pathological Early-Stage and EGFR Mutation.

BACKGROUND: CD44 isoforms serve as a marker for cancer stem cells. CD44 variant 9 (CD44v9) contributes to the defense against reactive oxygen species, resulting in resistance to chemoradiotherapy. However, the significance of CD44v9 in patients with lung adenocarcinoma is unknown. METHODS: We used immunohistochemical analysis to retrospectively analyze CD44v9 expression in 268 surgically resected lung adenocarcinomas and investigated the association between CD44v9 expression and patients' clinicopathological features. RESULTS: The expression of CD44v9 in 193 of 268 (72.0%) patients was significantly associated with early-stage cancer, low-grade tumors, absence of vessel and pleural invasion, and a mutated epidermal growth factor receptor (EGFR) gene. Multivariate logistic analysis revealed that CD44v9 expression was significantly associated with early-stage disease [odds ratio (OR) 0.29, 95% confidence interval (CI) 0.14-0.59; p < 0.001] and mutant EGFR (OR 2.53, 95% CI 1.06-6.04; p = 0.036). The percentage of CD44v9-positive tumors was higher in the earlier stages of disease; however, there was no significant difference in the survival of patients in each stage of disease who had positive or negative CD44v9 expression. CONCLUSION: CD44v9 was highly expressed in EGFR-mutant tumors, particularly in early-stage lung adenocarcinoma, suggesting that CD44v9 expression may play an important role in EGFR-mutant tumors.

Prognostic Impact of Programmed Death-Ligand 2 Expression in Primary Lung Adenocarcinoma Patients.

BACKGROUND: Programmed death-ligand 1 (PD-L1) expression on lung cancer cells is a prognostic marker and a predictive biomarker for response to immunotherapy. However, previous clinical trials have suggested that other programmed cell death 1 ligands, including programmed death-ligand 2 (PD-L2), might have clinical impacts. This study aimed to analyze the prognostic significance of PD-L2 expression in lung adenocarcinoma patients. METHODS: The study included 433 patients who underwent surgical resection for lung adenocarcinoma between 2003 and 2012 at Kyushu University Hospital. Both PD-L1 and PD-L2 expression were evaluated by immunohistochemistry. The cutoff value for PD-L2 positivity was set at 1% according to a time-dependent receiver operating characteristic curve for 5-year survival. RESULTS: Of the 433 patients, 306 (70.7%) were positive for PD-L2. No significant association between PD-L1 and PD-L2 expression was observed (P = 0.094). The multivariate analysis showed that the independent predictors of PD-L2 positivity were never-smoker status (P = 0.002), poor differentiation grade (P = 0.008), and advanced stage (P = 0.048). The PD-L2-positive patients had significantly shorter disease-free survival (DFS) (P = 0.018) and overall survival (OS) (P = 0.016). Both PD-L1 and PD-L2 positivity were independent predictors of OS (P < 0.001 and P = 0.027, respectively). In the subgroup analysis of the PD-L1-negative patients, PD-L2 positivity was significantly associated with shorter DFS (P = 0.018). CONCLUSIONS: The study demonstrated that the clinical characteristics of patients with PD-L1 expression may differ from those of patients with PD-L2 expression, and that both might contribute to poor prognoses. The potential role of PD-L2 expression as a predictive biomarker for response to immunotherapy should be investigated in future studies.

A Clinicopathological and Prognostic Analysis of PD-L2 Expression in Surgically Resected Primary Lung Squamous Cell Carcinoma.

BACKGROUND: Immunotherapy targeting programmed cell death-1 (PD-1) and programmed death-ligand 1 (PD-L1) has shown dramatic therapeutic effects for lung squamous cell carcinoma (SCC), and PD-L1 expression has been shown not only to be a predictive biomarker for response to immunotherapy but also a prognostic factor for lung SCC. However, the clinical significance of programmed death-ligand 2 (PD-L2), another PD-1 ligand, remains unclear. Therefore, we analyzed PD-L2 expression by immunohistochemistry in surgically resected primary lung SCC. PATIENTS AND METHODS: PD-L1 and PD-L2 expression on tumor cells were analyzed in 211 primary lung SCC specimens by immunohistochemistry. Additionally, numbers of CD3+, CD4+, and CD8+ tumor-infiltrating lymphocytes were also examined. RESULTS: The rates of positive PD-L2 expression were 77.3% and 67.3% using 5% and 10% cut-off values, respectively. Low PD-L2 expression on tumor cells was statistically associated with histological type (non-keratinizing/keratinizing) and lymphatic invasion. PD-L2-positive patients had significantly longer postoperative survival time (log-rank test; p = 0.0170 at 5% cut-off and p = 0.0500 at 10% cut-off). Furthermore, survival analysis according to PD-L1 and PD-L2 expression revealed that PD-L1-positive and PD-L2-negative patients had the most unfavorable prognosis. CONCLUSIONS: PD-L2 protein expression was associated with prognosis in primary lung SCC patients. PD-L2 expression might be a potential biomarker for response to PD-1/PD-L1-targeted immunotherapy, which should be investigated in future studies.

The evolution of surgical treatment for gastrointestinal cancers.

INTRODUCTION: According to the latest Japanese nationwide estimates, over a million Japanese people are newly diagnosed with cancer each year. Since gastrointestinal cancers account for more than 40% of all cancer-related deaths, it is imperative to formulate effective strategies to control them. MATERIALS AND METHODS, AND RESULTS: Basic drug discovery research Our research has revealed that the abnormal expression of regulators of chromosomal stability is a cause of cancers and identified an effective compound against cancers with chromosomal instability. We revealed the molecular mechanism of peritoneal dissemination of cancer cells via the CXCR4/CXCL12 axis to CAR-like cells and identified an MEK inhibitor effective against these tumors. Residual tumor cells after chemotherapy in colorectal cancer are LGR5-positive cancer stem cells and their ability to eliminate reactive oxygen species is elevated. The development of surgical procedures and devices In cases of gastric tube reconstruction for esophageal cancer, we determined the anastomotic line for evaluating the blood flow using ICG angiography and measuring the tissue O2 metabolism. We established a novel gastric reconstruction method (book-binding technique) for gastric cancer and a new rectal reconstruction method focusing on the intra-intestinal pressure resistance for rectal cancer. We established a novel tissue fusion method, which allows contact-free local heating and retains tissue viability with very little damage, and developed an understanding of the collagen-related processes that underpin laser-induced tissue fusion. Strategy to prevent carcinogenesis We succeeded in cleaving hepatitis B virus DNA integrated into the nucleus of hepatocytes using genome editing tools. The development of HCC from non-alcoholic steatohepatitis (NASH) may be prevented by metabolic surgery. CONCLUSION: We believe that these efforts will help to significantly improve the gastrointestinal cancer treatment and survival.

Correlation between CXCR4/CXCR7/CXCL12 chemokine axis expression and prognosis in lymph-node-positive lung cancer patients.

The CXCR4/CXCR7/CXCL12 chemokine axis plays important roles in the migration of tumor cells during cancer development by modulating site-specific distant metastasis including to regional lymph nodes. We investigated the correlation of these chemokine expressions to prognosis in lymph-node-positive non-small-cell lung cancer (NSCLC) patients. A total of 140 surgically resected specimens of primary site (PS) and metastatic lymph nodes (MLN) of NSCLC involving hilar and/or mediastinal lymph nodes (N1-2) were collected. CXCR4, CXCR7 and CXCL12 expressions were evaluated. Cox regression analysis was performed to determine whether these chemokines were independent prognostic factors in N1-2 NSCLC. High expression of CXCR4 in PS and CXCL12 in MLN was associated with poor overall survival (OS) (P = .025 and .033, respectively). Significant correlations between CXCR4 expression in PS and CXCL12 expression in MLN were observed (P = .040). There was significant difference in OS between 2 groups according to expressions of CXCR4 in PS and CXCL12 in MLN (P = .0033). Expression of CXCL12 in MLN was identified as an independent prognostic factor (HR 1.79, 95% CI 1.08-3.04, P = .023). CXCL12 in MLN was mainly expressed by tumor cells compared with stromal cells (56% vs 25%, respectively, P < .0001). CXCR4/CXCL12 may play roles in tumor progression in MLN and is associated with poor prognosis of lymph-node-positive NSCLC patients.

The C-Reactive Protein/Albumin Ratio is a Novel Significant Prognostic Factor in Patients with Malignant Pleural Mesothelioma: A Retrospective Multi-institutional Study.

BACKGROUND: Malignant pleural mesothelioma (MPM), a devastating neoplasm, is traditionally considered to be resistant to antitumor therapy. Identification of clinical prognostic indicators is therefore needed. Although the C-reactive protein/albumin ratio (CAR) has been used to predict the prognosis of many types of malignancy, its utility in patients with MPM is unknown. METHODS: The data of 100 patients diagnosed as having MPM from 1995 to 2015 at the National Kyushu Cancer Center and Kyushu University were analyzed. The CAR was calculated as serum C-reactive protein concentration divided by albumin concentration. A cutoff for CAR was set at 0.58 according to a receiver operating characteristics curve for 1-year survival. RESULTS: Thirty-five of the 100 (35.0%) patients were classified as having a high CAR. A high CAR was significantly associated with advanced clinical stage (p < 0.001) and chemotherapy alone (p = 0.002). Patients with a high CAR had significantly shorter overall survival (OS) (p < 0.001) and disease- or progression-free survival (DFS/PFS) (p < 0.001). These associations between CAR and prognosis remained significant after propensity score-matching. In multivariate analysis, a high CAR was an independent predictor of shorter OS and DFS/PFS (p = 0.003 and p = 0.008, respectively). Multivariate analyses of the subgroups of patients who had received chemotherapy and of patients who had undergone surgery also showed that a high CAR was an independent predictor of shorter OS and DFS/PFS. CONCLUSIONS: CAR is an independent predictor of prognosis in MPM patients. This prognostic index contributes to clinicians' ability to predict benefit from treatment. Further larger, prospective studies are necessary to validate these findings.

Clinical and Genetic Implications of Mutation Burden in Squamous Cell Carcinoma of the Lung.

BACKGROUND: Lung squamous cell carcinoma (LSCC) is a major histological subtype of lung cancer. In this study, we investigated genomic alterations in LSCC and evaluated the clinical implications of mutation burden (MB) in LSCC. METHODS: Genomic alterations were determined in Japanese patients with LSCC (N = 67) using next-generation sequencing of 415 known cancer genes. MB was defined as the number of non-synonymous mutations per 1 Mbp. Programmed death-ligand 1 (PD-L1) protein expression in cancer cells was evaluated by immunohistochemical analysis. RESULTS: TP53 gene mutations were the most common alteration (n = 51/67, 76.1%), followed by gene alterations in cyclin-dependent kinase inhibitor 2B (CDKN2B; 35.8%), CDKN2A (31.3%), phosphatase and tensin homolog (30.0%), and sex-determining region Y-box 2 (SOX2, 28.3%). Histological differentiation was significantly poorer in tumors with high MB (greater than or equal to the median MB) compared with that in tumors with low MB (less than the median MB; p = 0.0446). The high MB group had more tumors located in the upper or middle lobe than tumors located in the lower lobe (p = 0.0019). Moreover, cancers in the upper or middle lobes had significantly higher MB than cancers in the lower lobes (p = 0.0005), and tended to show higher PD-L1 protein expression (p = 0.0573). SOX2 and tyrosine kinase non-receptor 2 amplifications were associated with high MB (p = 0.0065 and p = 0.0010, respectively). CONCLUSIONS: The MB level differed according to the tumor location in LSCC, suggesting that the location of cancer development may influence the genomic background of the tumor.

Clinical Impact and Risk Factors for Skeletal Muscle Loss After Complete Resection of Early Non-small Cell Lung Cancer.

BACKGROUND: A relationship between sarcopenia diagnosed by skeletal muscle area (SMA) and poor prognosis in cancer patients has recently been reported. This study aimed to clarify the clinical significance of postoperatively decreased SMA in patients with early non-small cell lung cancer (NSCLC). METHODS: This study selected 101 patients with pathologic stage 1 NSCLC who had undergone pre- and postoperative (~ 1 year) computed tomography scans and lobectomy between 2005 and 2010 at Kyushu University Hospital. The post/pre ratio was defined as the postoperative normalized SMA (cm2/m2) at the 12th thoracic vertebra level divided by the preoperative normalized SMA. The cutoff value for the post/pre ratio was set at 0.9. RESULTS: The study classified 31 patients (30.7%) as having decreased SMA. Poor performance status (PS) was significantly associated with decreased SMA (p = 0.048). The patients with decreased SMA had a significantly shorter disease-free survival (DFS) (p < 0.001) and overall survival (OS) (p < 0.001) than the other patients. Decreased SMA was found to be an independent prognostic factor for DFS (p = 0.010) and OS (p = 0.0072). The independent risk factors for skeletal muscle loss included poor PS (PS ≥ 1) and obstructive ventilatory impairment [forced expiratory volume (FEV) 1% < 70%]. CONCLUSIONS: Skeletal muscle loss after surgery is significantly associated with postoperative poor outcomes for patients with early NSCLC. Patients with poor PS, obstructive ventilatory impairment, or both need careful support to maintain their skeletal muscle mass. Future prospective studies may clarify whether physical activity and nutritional support improve postoperative prognosis.