Ken Katono

Prognostic Significance of Nestin Expression in Resected Non-small Cell Lung Cancer

BACKGROUND Nestin is a class 6 intermediate filament protein expressed in stem/progenitor cells during CNS development. Nestin expression has been detected in many kinds of tumors and was reported in a recent small-scale study in non-small cell lung cancer (NSCLC). We investigated the relationships between nestin expression and clinicopathologic parameters and determined its prognostic significance concerning survival in patients with resected NSCLC. METHODS Nestin expression in tumor cells was studied immunohistochemically in 171 consecutive patients with NSCLC, and associations with clinicopathologic parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of nestin expression on survival. RESULTS Nestin expression was observed in tumor cell samples in 27 of the 171 patients with NSCLC (15.8%). Nestin had only cytoplasmic expression. Clinicopathologically, nestin expression was significantly associated with squamous cell carcinoma (P = .001), poorer differentiation (P = .007), lymph node metastasis (P = .008), intratumoral vascular invasion (P = .003), intratumoral lymphatic invasion (P = .008), pleural invasion (P = .039), and poorer prognosis (P < .001). Multivariable analysis confirmed that nestin expression increased the hazard of death after adjusting for other clinicopathologic factors (hazard ratio, 2.75; 95% CI, 1.39-5.46). CONCLUSIONS The present study suggests that nestin expression is a prognostic indicator of poorer survival probability for patients with resected NSCLC and may be used as a potential marker for select patients who should receive adjuvant chemotherapy.

Circulating tumor cells as a prognostic factor in patients with small cell lung cancer

The detection of circulating tumor cells (CTCs) in peripheral blood is currently an important field of study. Detection of CTCs by the OBP-401 assay (TelomeScan®) has previously been reported to be useful in the diagnosis, prognosis and evaluation of therapeutic efficacy in breast and gastric cancer. The aim of the present study was to evaluate the OBP-401 assay as a novel method of detecting CTCs of small cell lung cancer (SCLC) patients and to evaluate whether CTC count is associated with prognosis. Prospectively, 30 consecutively diagnosed SCLC patients who had commenced chemotherapy or chemoradiotherapy were enrolled as subjects of the current study. Peripheral blood specimens were collected from the SCLC patients prior to and following the initiation of treatment and the viable CTCs were detected in the specimens following incubation with a telomerase-specific, replication-selective, oncolytic adenoviral agent, which was carrying the green fluorescent protein gene. CTCs were detected in 29 patients (96%). The group of 21 patients with a CTC count of <2 cells/7.5 ml prior to treatment (baseline) had a significantly longer median survival time than the group of eight patients with a CTC count of ≥2 cells/7.5 ml prior to treatment (14.8 and 3.9 months, respectively; P=0.007). The results of a multivariate analysis showed that the baseline CTC count was an independent prognostic factor for survival time (hazard ratio, 3.91; P=0.026). Among the patients that achieved a partial response to treatment, patients who had a CTC count of <2 cells/7.5 ml following two cycles of chemotherapy tended to have a longer median progression-free survival compared with patients who had a CTC count of ≥2 cell/7.5 ml (8.3 and 3.8 months, respectively; P=0.07). Therefore, CTCs may be detected via OBP-401 assay in SCLC patients and the CTC count prior to treatment appears to be a strong prognostic factor.

Pemetrexed for previously treated patients with non-small cell lung cancer and differences in efficacy according to thymidylate synthase expression.

The purpose of this study was to evaluate the efficacy of pemetrexed monotherapy in previously treated patients with advanced non-small cell lung cancer (NSCLC) including salvage treatment, and to evaluate whether thymidylate synthase (TS) expression is a predictor for pemetrexed efficacy. Hundred and four previously treated patients with advanced NSCLC who received pemetrexed monotherapy were retrospectively evaluated for clinical efficacy and toxicity. If available, tissue specimens of patients were also analyzed immunohistochemically for TS expression. The patients’ median age was 65 years (range: 43–82). An overall response rate of 9.6% and a median progression-free survival (PFS) time of 3.4 months were achieved. The response rates for the second-line, third-line, fourth-line or further treatments were 9.1, 9.3 and 10.2% (p = 0.33); the median PFS were 3.3, 3.2 and 3.8 months (p = 0.21). The median follow-up duration was 14.9 months; the median overall survival (OS) was 11.9 months. The median PFS and OS were significantly longer in the TS-negative group than in the TS-positive group (5.8 months vs. 1.6 months; p = 0.03, and 14.7 months vs. 8.6 months; p = 0.04, respectively). Pemetrexed monotherapy could be considered as an option in the fourth or later lines of treatment of previously treated patients with advanced NSCLC as well as a second- or third-line treatment, and TS expression may be a potentially predictive factor for pemetrexed efficacy in NSCLC patients.

The clinicopathological significance of Lgr5 expression in lung adenocarcinoma

BACKGROUND The leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5), also known as Gpr49, has been identified as a marker of crypt basal columnar stem cells along the gastrointestinal tract and of bulge stem cells in the hair follicle. The aims of this study were to immunohistochemically examine Lgr5 expression in surgically resected non-small cell lung carcinomas (NSCLC), and evaluate the relationships between Lgr5 expression and the clinicopathological parameters and prognosis of patients. METHODS Lgr5 expression was immunohistochemically studied in 266 consecutive resected NSCLCs, and its associations with clinicopathological parameters including TTF-1 and CDX-2 expressions were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of Lgr5 expression on survival. RESULTS Lgr5 was detected only in tumors with adenocarcinoma histology, and 16 cases were judged as positive. Among lung adenocarcinomas, Lgr5 expression was significantly associated with a larger tumor size (> 5 cm) (P = 0.033), higher pathological TNM stage of the disease (stage II and III) (P = 0.025), TTF-1-negative adenocarocinoma (P = 0.042), and poorer prognosis (P = 0.026). However, Lgr5 expression was not an independent predictor of poorer survival after controlling for clinicopathological factors. CONCLUSIONS The present study reveals that Lgr5 is expressed in a subset of lung adenocarcinoma, and its expression is related to some clinicopathological parameters and a poorer prognosis, although further studies are required to clarify the biological function of Lgr5 in lung adenocarcinoma.

Diagnostic and Prognostic Significances of MUC5B and TTF-1 Expressions in Resected Non-Small Cell Lung Cancer

To investigate the relationships between the expression of MUC5B and clinicopathological parameters, the expression of MUC5B was immunohistochemically studied. MUC5B expression was observed in 129 of 198 (65.2%) adenocarcinomas and in 4 of 49 (8.2%) squamous cell carcinomas (P < 0.00001). MUC5B expression was significantly associated with poorer differentiation (P = 0.0303), higher pathological TNM stage (p = 0.0153) and poorer prognosis of adenocarcinoma patients (P = 0.0017). Multivariable analysis with Cox proportional hazards models confirmed that MUC5B expression increased the hazard of death after adjusting for other clinicopathological factors (HR = 2.66; 95%CI, 1.26–5.61). We also immunohistochemically evaluated TTF-1 expression and found that the combination of MUC5B with TTF-1 is a useful marker for adenocarcinomas. The diagnostic accuracies of TTF-1 and MUC5B for adenocarcinoma were 83.8% and 70.4%, respectively. The accuracy increased to 94.3% when the two factors were combined. In survival analysis, the MUC5B(High)/TTF-1(−) group was significantly associated with a poorer outcome compared with the MUC5B(Low)/TTF-1(+) group (p < 0.0001). The present study suggested that the combination of MUC5B and TTF-1 expression is useful for discriminating adenocarcinomas from squamous cell carcinomas, yielding prognostic significance in patients with lung adenocarcinoma.

Impact of PD-L1 Expression in Patients with Surgically Resected Non-Small-Cell Lung Cancer

Background: Immunotherapy can become a crucial therapeutic option to improve the prognosis of patients with non-small-cell lung cancer (NSCLC). Here, we evaluated the impact of programmed cell death ligand-1 (PD-L1) expression in surgically resected NSCLCs. Methods: We estimated PD-L1 expression in 229 consecutive NSCLC specimens using rabbit polyclonal antibodies to human PD-L1 in a SP263 immunohistochemical assay and evaluated PD-L1 expression for potential associations with clinicopathological parameters and survival time. Results: PD-L1 expression was significantly higher in tumors from men or current smokers. Squamous cell carcinoma histology was independently associated with high PD-L1 expression according to multivariate analysis (p = 0.015). The 5-year survival rate of patients was 70%, and the difference in the 5-year survival rate according to PD-L1 expression was not statistically significant (high expression group [67%] vs. low expression group [68%]); however, the squamous cell carcinoma group exhibited significantly lower 5-year survival rates as compared to the non-squamous cell carcinoma group (53 and 71%, respectively; p = 0.026). Conclusion: Here, we revealed high PD-L1 expression and poor prognosis observed in patients with surgically resected squamous NSCLC as compared with non-squamous NSCLC. Our results support the identification of patient subsets that most likely respond to anti-PD-1 therapy as the first step in precision medicine.

Calnexin is a novel sero-diagnostic marker for lung cancer

To develop sero-diagnostic markers for lung cancer, we generated monoclonal antibodies using lung adenocarcinoma (AC)-derived A549 cells as antigens by employing the random immunization method. Hybridoma supernatants were immunohistochemically screened for antibodies with AMeX-fixed and paraffin-embedded A549 cell preparations. Positive clones were monocloned twice through limiting dilutions. From the obtained monoclonal antibodies, one designated as KU-Lad-001 was recognized as calnexin (CANX) based on immunoprecipitation and MADLI TOF/TOF-MS analysis. To evaluate the utility of this antibody as a sero-diagnostic marker for lung cancer, we performed reverse-phase protein array analysis with samples of 195 lung cancer patients and 100 healthy controls. The CANX expression levels were significantly higher in lung cancer patients than in healthy controls (P<0.0001), and the area under the curve of ROC was 0.980, with 96.9% specificity and 99.0% sensitivity. Furthermore, since CANX was also detected in stage I disease, the serum CANX levels should be applicable markers discriminating lung cancer patients from healthy controls and possibly used in the detection of early lung cancer. To our knowledge, the present results provide evidence that CANX may be a novel sero-diagnostic marker for lung cancer.

Effect of gefitinib on warfarin antithrombotic activity.

BackgroundDespite the literature indicating adverse interactions between warfarin and cytotoxic agents, whether such an interaction occurs when warfarin and gefitinib are used concomitantly is unknown. We analyzed the prevalence of the concomitant use of warfarin and gefitinib, and the incidence of prothrombin time-international normalized ratio (PT-INR) alterations or adverse interactions in concomitant users of warfarin and gefitinib.MethodsWe conducted a retrospective study of patients with non-small cell lung cancer treated at the Kitasato University Hospital who received concomitant warfarin and gefitinib between September 2002 and January 2007. Medical information, including the indication for warfarin use, warfarin dosing and dosing changes, and exposure to gefitinib were collected from computerized databases and medical records.ResultsTwelve (4.1%) of 296 patients treated with gefi— tinib received warfarin. PT-INR elevation occurred in 6 patients (50.0%). Two (16.7%) of the 12 patients had liver metastases. Liver dysfunction was associated with PT-INR elevation (P = 0.0100).ConclusionAs there is a possibility of PT-INR abnormalities occurring during the concomitant use of gefitinib and warfarin, clinicians should be aware of this interaction. Because of the potentially severe consequences of this interaction, close monitoring of PT-INR and warfarin dose adjustment are recommended for patients receiving warfarin and gefitinib, especially during the first 2 weeks in the beginning of warfarin therapy.

S100A16 is a Prognostic Marker for Lung Adenocarcinomas.

BACKGROUND Many functional molecules controlling diverse cellular function are included in low-molecular weight proteins and peptides. MATERIALS AND METHODS To identify proteins controlling function in lung adenocarcinomas (AC), we performed two-dimensional gel electrophoresis employing tricine-SDS polyacrylamide in the second dimension (tricine 2-DE). This system was able to detect proteins under 1 kDa even with post- translational modifications. To confirm the utility of detected proteins as novel tumor markers for AC, we performed immunohistochemical analysis using 170 formalin-fixed and paraffin-embedded lung AC tissues. RESULTS Tricine 2-DE revealed that five proteins including S100A16 were overexpressed in lung AC-derived cells compared with lung squamous cell carcinoma, small cell carcinoma, and large cell neuroendocrine carcinoma- derived cells. Immunohistochemically, S100A16 showed various subcellular localization in lung cancer tissues and a membranous staining status was correlated with the T-factor (P=0.0008), pathological stage (P=0.0015), differentiation extent (P=0.0001), lymphatic invasion (P=0.0007), vascular invasion (P=0.0001), pleural invasion (P=0.0087), and gender (P=0.039), but not with the age or smoking history. More importantly, membranous staining of S100A16 was significantly correlated with a poorer overall survival of either stage I (P=0.0088) or stage II / III (P=0.0003) lung AC patients, and multivariate analysis confirmed that membranous expression of S100A16 was an independent adverse prognostic indicator (P=0.0001). CONCLUSIONS The present results suggest that S100A16 protein is a novel prognostic marker for lung AC.

Prognostic Significance of MYH9 Expression in Resected Non-Small Cell Lung Cancer

Introduction Myosin-9 (MYH9) belongs to the myosin superfamily of actin-binding motor protein. Recently, MYH9 has been thought to be associated with cancer cell migration, invasion, and metastasis. The aims of this study were to immunohistochemically examine MYH9 expression in surgically resected non-small cell lung cancer (NSCLC), and evaluate its correlations with clinicopathological parameters and the prognosis of patients. Methods MYH9 expression was immunohistochemically studied in 266 consecutive resected NSCLCs, and its associations with clinicopathological parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of MYH9 expression on survival. Results MYH9 expression was detected in 102 of 266 (38.3%) NSCLCs. MYH9 expression was significantly correlated with the adenocarcinoma histology (P = 0.014), poorer differentiation ((P = 0.033), intratumoral vascular invasion and lymphatic invasion ((P = 0.013 and P = 0.045 respectively), and a poorer prognosis ((P = 0.032). In addition, multivariable analysis revealed that MYH9 expression independently predicted a poorer survival (HR, 2.15; 95%CI, 1.17-3.92; (P = 0.01). Conclusion The present study revealed that MYH9 is expressed in a subset of NSCLC with a more malignant nature, and its expression is an indicator of a poorer survival probability.