Insulinoma-Associated Protein 1 Is a Crucial Regulator of Neuroendocrine Differentiation in Lung Cancer.

Insulinoma-associated protein 1 (INSM1) is expressed exclusively in embryonic developing neuroendocrine (NE) tissues. INSM1 gene expression is specific for small-cell lung cancer (SCLC), along with achaete-scute homolog-like 1 (ASCL1) and several NE molecules, such as chromogranin A, synaptophysin, and neural cell adhesion molecule 1. However, the underlying biological role of INSM1 in lung cancer remains largely unknown. We first showed that surgically resected SCLC samples specifically expressed INSM1. Forced expression of the INSM1 gene in adenocarcinoma cell lines (H358 and H1975) induced the expression of ASCL1, brain-2 (BRN2), chromogranin A, synaptophysin, and neural cell adhesion molecule 1; in contrast, knockdown of the INSM1 gene by siRNA in SCLC (H69 and H889) decreased their expression. However, forced/knockdown expression of ASCL1 and BRN2 did not affect INSM1 expression. A chromatin immunoprecipitation study revealed that INSM1 bound to the promoter region of the ASCL1 gene. A xenotransplantation assay using tet-on INSM1 gene-transfected adenocarcinoma cell lines demonstrated that INSM1 induced NE differentiation and growth inhibition. Furthermore, we found that INSM1 was not expressed in non-small-cell lung cancer and some SCLC cell lines expressing Notch1-Hes1. By forced/knockdown expression of Notch1 or Hes1 genes, we revealed that Notch1-Hes1 signaling suppressed INSM1, as well as ASCL1 and BRN2. INSM1, expressed exclusively in SCLC, is a crucial regulator of NE differentiation in SCLCs, and is regulated by the Notch1-Hes1 signaling pathway.

Novel approach to pleurodesis with 50 % glucose for air leakage after lung resection or pneumothorax.

PURPOSE: Pleurodesis is performed in patients demonstrating air leakage after lung resection and in those with pneumothorax who must avoid surgery. However, there have so far been very few reports of pleurodesis with 50 % glucose. We herein examined the feasibility and effectiveness of this novel pleurodesis technique. METHODS: Thirty-five patients after lung resection and 11 pneumothorax patients without surgery were treated with pleurodesis using 50 % glucose. Approximately, 200 mL of 50 % glucose solution was injected into the pleural space and repeated until the air leakage stopped. Cases in which the air leakage did not stop after three injections were considered to be unsuccessful and subsequently treated with conventional pleurodesis using OK-432. RESULTS: Thirty-nine patients were successfully treated with 50 % glucose, although 7 patients required further treatment with OK-432. The unsuccessful group had some pulmonary comorbidities (P < 0.001), and the pleural effusion volume after pleurodesis was less than that in the successful group (P < 0.001). Although the air leakage did not stop in unsuccessful patients, the amount of air leakage markedly decreased. A temporary elevation of the blood sugar level was observed in 20 patients, but no other side effects had appeared. CONCLUSIONS: Pleurodesis with 50 % glucose is an easy, safe, and effective treatment modality. It is therefore considered to be a useful alternative method for pleurodesis.

MUC4 expression correlates with poor prognosis in small-sized lung adenocarcinoma.

The mortality of lung cancer remains high, despite improved diagnostic techniques that allow small lung tumors to be detected. In this study, we evaluated the prognostic significance of the tracheal mucin MUC4 by immunohistochemical investigation of the expression profiles of MUC4, ErbB2, p27 and MUC1 in lung adenocarcinoma specimens (non-bronchiolo-alveolar type, < or =3cm) from 185 patients. MUC4 is a membrane mucin, similarly to MUC1, and in addition MUC4 functions as an intra-membrane ligand for receptor tyrosine kinase ErbB2 and is associated with regulation of p27. However, MUC4 expression was found to be unrelated to expression of MUC1, ErbB2 and p27 in small-sized lung adenocarcinomas. The disease-free interval (DFI) and survival rate of 25 patients with high MUC4 expression (> or =25% of neoplastic cells stained) were significantly lower than those of 160 patients with low MUC4 expression (<25% of neoplastic cells stained) (P<0.05), whereas ErbB2 and p27 expression showed no significant correlation with DFI and survival. Univariate analysis showed that high MUC4 and p27 expression correlated with blood vessel invasion (P=0.0004), and MUC4 expression was frequently detected in regions of stromal invasion. In addition, the survival rate of stage IA patients with high MUC4 expression was significantly lower than that of stage IA patients with low MUC4 expression (P<0.05). In conclusion, high MUC4 expression in small-sized lung adenocarcinomas correlates with a short DFI and a poor survival rate. Therefore, MUC4 expression might be a new independent factor for prediction of outcome and indication of poor prognosis in lung adenocarcinoma.

Adenosquamous carcinoma of the lung: surgical results as compared with squamous cell and adenocarcinoma cases.

OBJECTIVES: An adenosquamous carcinoma (ASC) of the lung is a relatively rare tumor. In this multi-institutional cohort study, we tested the hypothesis that an ASC exhibits more aggressive clinical behavior as compared to adenocarcinoma (AC) and squamous cell carcinoma (SC). METHODS: This retrospective cohort study used a prospective database produced by the Japan National Hospital Organization Study Group for Lung Cancer over a 7-year period (operations from 1997 to 2003, follow-up data until March 2010). During that period, 4668 cases underwent an operation for various types of primary malignant lung tumors. When a sample from a tumor comprised at least 20% each of SC and AC, the case was classified as ASC. Pathologic staging was done according to the seventh edition of the International Union against Cancer (UICC) Tumor Node Matastasis (TNM) classification of malignant tumors. RESULTS: We identified 114 patients with ASC (2.4%), 2993 with AC (64.2%), and 1369 with SC (29.3%). Kaplan-Meier survival curves for all stage cases, p-stage IA, IB, and IIIA tumors indicated that ASC cases had the least favorable survival. The 5-year survival rates for all stage cases were 23.3% for ASC, 58.0% for AC (p < 0.0001), and 40.8% for SC (p < 0.0001). The 5-year survival rates for p-stage IA were 42.0% for ASC, 81.8% for AC (p = 0.0005), and 63.4% for SC not significant (NS), while those for p-stage IB were 19.3%, 65.3% (p = 0.0024), and 46.8% (NS), respectively, and those for p-stage IIIA were 17.8%, 24.8% (p = 0.0154), and 18.8% (NS), respectively. There was a tendency for greater survival differences between ASC and AC in earlier tumor stages. A step-wise multivariable model demonstrated that sex, age, performance status, histology, tumor size, p-stage, operative method, and neoadjuvant/adjuvant therapy were independent prognostic factors. CONCLUSION: ASC of the lung is more aggressive than AC and SC. The decreased survival of patients with ASC as compared with either of those single histology tumors suggests the need for a clinical trial of adjuvant chemotherapy that includes early-stage patients.

A micropapillary pattern is predictive of a poor prognosis in lung adenocarcinoma, and reduced surfactant apoprotein A expression in the micropapillary pattern is an excellent indicator of a poor prognosis.

A micropapillary pattern is defined as papillary tufts without a fibrovascular core and is known to be a factor that indicates a poor prognosis in numerous cancers. However, their role in lung adenocarcinoma has not been investigated widely. In 185 cases of small-size lung adenocarcinoma (< or =3 cm), cases with a micropapillary pattern ratio of more than 1% (analyzed by NIH image) were defined as micropapillary pattern positive. Correlations between the micropapillary pattern and clinicopathological factors were investigated and immunohistochemical expression of mucin and various antigens was examined in regions with and without micropapillary patterns. Micropapillary pattern-positive tumors (micropapillary pattern ratio > or =1%) were observed in 11.4% of cases (21/185) and the micropapillary pattern ratio correlated with TNM stage (P=0.0002), lymphatic invasion (P=0.0002) and lymph node metastasis (P=0.03). Disease-free interval (P<0.0002) and survival (P=0.027) were significantly shorter for micropapillary pattern-positive patients, and micropapillary pattern-positive stage IA cases also had a significantly shorter disease-free interval (P<0.0001). MUC1 was expressed strongly across the surface of the micropapillary structure, whereas MUC4 tended to show lower expression in the micropapillary pattern. It was noteworthy that the disease-free interval in patients with high surfactant apoprotein A expression was significantly better than in patients with low surfactant apoprotein A expression (P=0.03), and no recurrence or death occurred in patients with high surfactant apoprotein A expression. Our results show that the micropapillary pattern ratio correlates with lymphatic invasion and lymph node metastasis, and that a high micropapillary pattern ratio leads to a poor prognosis. High MUC1 expression on the surface is an important characteristic of a micropapillary pattern, and reduced surfactant apoprotein A expression in the micropapillary pattern may be an excellent indicator for poor prognosis in small-size lung adenocarcinoma.

Sparganum mansoni parasitic infection in the lung showing a nodule.

Reported herein is a 57-year-old man infected by Sparganum mansoni, a kind of tapeworm, showing a solitary nodule of the middle lobe of the right lung. Because a transbronchial biopsy could not diagnose the nodule, a right middle lobectomy was performed on suspicion of malignant tumor. The lesion was diagnosed as sparganosis by histological and immuno-serological examinations. Histological examination revealed granulomatous inflammation with neutrophil and eosinophil infiltration around the worm and interstitial pneumonia surrounding the nodule. Moreover, vasculitis with foreign body giant cell was seen around the lesion. To the authors' knowledge this is the second case of sparganosis limited in the lung, and the current report presents the first detailed histological description of a pulmonary sparganosis case.