ASC amino-acid transporter 2 (ASCT2) as a novel prognostic marker in non-small cell lung cancer.

BACKGROUND: ASC amino-acid transporter 2 (ASCT2) is a major glutamine transporter that has an essential role in tumour growth and progression. Although ASCT2 is highly expressed in various cancer cells, the clinicopathological significance of its expression in non-small cell lung cancer (NSCLC) remains unclear. METHODS: One hundred and four patients with surgically resected NSCLC were evaluated as one institutional cohort. Tumour sections were stained by immunohistochemistry (IHC) for ASCT2, Ki-67, phospho-mTOR (mammalian target of rapamycin), and CD34 to assess the microvessel density. Two hundred and four patients with NSCLC were also validated by IHC from an independent cohort. RESULTS: ASC amino-acid transporter 2 was expressed in 66% of patients, and was closely correlated with disease stage, lymphatic permeation, vascular invasion, CD98, cell proliferation, angiogenesis, and mTOR phosphorylation, particularly in patients with adenocarcinoma (AC). Moreover, two independent cohorts confirmed that ASCT2 was an independent marker for poor outcome in AC patients. CONCLUSIONS: ASC amino-acid transporter 2 expression has a crucial role in the metastasis of pulmonary AC, and is a potential molecular marker for predicting poor prognosis after surgery.

Clinicopathological and prognostic significance of interleukin-8 expression and its relationship to KRAS mutation in lung adenocarcinoma.

BACKGROUND: On the basis of our recent findings of oncogenic KRAS-induced interleukin-8 (IL-8) overexpression in non-small cell lung cancer, we assessed the clinicopathological and prognostic significances of IL-8 expression and its relationship to KRAS mutations in lung adenocarcinomas. METHODS: IL-8 expression was examined by quantitative RT-PCR using 136 of surgical specimens from lung adenocarcinoma patients. The association between IL-8 expression, clinicopathological features, KRAS or EGFR mutation status and survival was analysed. RESULTS: IL-8 was highly expressed in tumours from elderly patients or smokers and in tumours with pleural involvement or vascular invasion. In a non-smokers' subgroup, IL-8 level positively correlated with age. IL-8 was highly expressed in tumours with KRAS mutations compared with those with EGFR mutations or wild-type EGFR/KRAS. Lung adenocarcinoma patients with high IL-8 showed significantly shorter disease-free survival (DFS) and overall survival (OS) than those with low IL8. DFS and OS were significantly shorter in the patients with mutant KRAS/high IL-8 than in those with wild-type KRAS/low IL-8. Cox regression analyses demonstrated that elevated IL-8 expression correlated with unfavourable prognosis. CONCLUSIONS: Our findings suggest that IL-8 expression is associated with certain clinicopathological features including age and is a potent prognostic marker in lung adenocarcinoma, especially in oncogenic KRAS-driven adenocarcinoma.

Autocrine angiogenic vascular prosthesis with bone marrow transplantation.

Synthetic vascular prostheses are foreign bodies, so that blood coagulation can occur on their luminal surfaces, causing graft occlusion very frequently in prostheses of small diameter. A vascular prosthesis needs angiogenesis for endothelialization of the luminal surface, as endothelial cells have natural and permanent antithrombogenic properties. To induce capillary growth into the graft, we developed a method of transplanting bone marrow cells, which are primitive, strong enough to survive, and create blood cells, resulting in the inducement of capillary growth. In an animal experiment, marrow cells were infiltrated into the walls of long-fibril expanded polytetrafluoroethylene (ePTFE) vascular grafts. The grafts were implanted in the abdominal aortic position of 24 dogs autologously. Marrow cells survived and continued exogenous hemopoiesis for up to six months and were immunohistochemically reactive to basic fibroblast growth factor (bFGF). All the grafts older than three weeks had complete endothelialization and maintained their patency. Twenty grafts without bone marrow were implanted as controls. Endothelialization was present at anastomotic sites, but other areas were covered with fresh thrombi. Four out of seven control grafts were patent with endothelial cell lining at six months, but three were occluded and one of the four grafts was still covered with a thrombus layer. Bone marrow with its unique native properties produced autocrine angiogenicity in the graft.

Thin film growth of CaAgAs by molecular beam epitaxy.

We have grown thin films of CaAgAs by molecular beam epitaxy, which was theoretically proposed to be a topological insulator. The temperature dependence of resistivity and the carrier concentration at 4 K were similar to the reported results of bulk samples. However, the magnetoresistance exhibited a steep increase at low magnetic fields, a behavior not observed for bulk samples. This steep increase of resistivity is ascribable to the weak antilocalization effect and provides clues to the nature of the topological surface state of CaAgAs.

Clinicopathological significance of Fhit protein expression in stage I non-small cell lung carcinoma.

Abnormalities in structure and expression of the FHIT gene have been detected in a considerable fraction of primary lung tumors. Previous reports indicated that FHIT gene alterations can be simply detected by immunohistochemical methods. Therefore, we investigated the association of Fhit expression with clinicopathological features and allelic imbalance (AI) at the FHIT locus in 105 stage I non-small cell lung cancers (NSCLC) by the immunohistological method and PCR analysis. Thirty-six of 105 (34%) tumors showed marked reduction of Fhit immunoreactivity. Fhit expression was markedly reduced in most squamous cell carcinomas (24 of 28, 86%), whereas such a reduction was detected only in a small subset of adenocarcinomas (7 of 67, 10%; P < 0.001). A marked reduction of Fhit protein expression was observed more frequently in patients with a smoking history (32 of 80, 40%) than in patients without a smoking history (4 of 25, 16%; P = 0.013). These results indicate that FHIT gene alterations preferentially occur in squamous cell carcinomas and in smokers. Furthermore, a reduction of Fhit protein expression in tumor cells was associated with a poorer survival of patients with stage I NSCLC, irrespective of histological subtypes of tumors (P = 0.005; log-rank test). Fhit expression was reduced preferentially in tumors with AI at the FHIT locus; however, AI at the FHIT locus did not correlate with patients' survival (P = 0.262; log-rank test). These results suggested that Fhit protein expression could be a useful molecular marker for the prognosis of patients with surgically resected stage I NSCLC.

Inactivation of human SRBC, located within the 11p15.5-p15.4 tumor suppressor region, in breast and lung cancers.

A cDNA clone encoding human SRBC [serum deprivation response factor (sdr)-related gene product that binds to c-kinase] was isolated in a yeast two-hybrid screening, with amino acids 1-304 of BRCA1 as the probe. The human SRBC gene (hSRBC) was mapped to chromosome region 11p15.5-p15.4, close to marker D11S1323, at which frequent loss of heterozygosity (LOH) has been observed in sporadic breast, lung, ovarian, and other types of adult cancers as well as childhood tumors. hSRBC-coding region mutations including frame shift and truncation mutations were detected in a few ovarian and lung cancer cell lines. More significantly, the expression of hSRBC protein was down-regulated in a large fraction [30 (70%) of 43] of breast, lung, and ovarian cancer cell lines, whereas strong expression of hSRBC protein was detected in normal mammary and lung epithelial cells. The down-regulation of hSRBC expression in cancer cells was associated with hypermethylation of CpG dinucleotides in its promoter region, and 3 (60%) of 5 primary breast tumors and 11 (79%) of 14 primary lung tumors were also found to be hypermethylated. Treatment of breast cancer MCF7 cells with 5'azacytidine and Trichostatin A resulted in expression of hSRBC, confirming DNA methylation as the mode of inactivation. Our results suggest that epigenetic or mutational inactivation of hSRBC may contribute to the pathogenesis of several types of human cancers, marking hSRBC as a candidate tumor suppressor gene.

Overexpression of candidate tumor suppressor gene FUS1 isolated from the 3p21.3 homozygous deletion region leads to G1 arrest and growth inhibition of lung cancer cells.

Recently we identified FUS1 as a candidate tumor suppressor gene (TSG) in the 120 kb 3p21.3 critical region contained in nested lung and breast cancer homozygous deletions. Mutation of FUS1 is infrequent in lung cancers which we have confirmed in 40 other primary lung cancers. In addition, we found no evidence for FUS1 promoter region methylation. Because haploinsufficiency or low expression of Fus1 may play a role in lung tumorigenesis, we tested the effect of exogenously induced overexpression of Fus1 protein and found 60-80% inhibition of colony formation for non-small cell lung cancer lines NCI-H1299 (showing allele loss for FUS1) and NCI-H322 (containing only a mutated FUS1 allele) in vitro. By contrast, a similar level of expression of a tumor-acquired mutant form of FUS1 protein did not significantly suppress colony formation. Also, induced expression of Fus1 under the control of an Ecdysone regulated promoter decreased colony formation 75%, increased the doubling time twofold, and arrested H1299 cells in G1. In conclusion, our data are consistent with the hypothesis that FUS1 may function as a 3p21.3 TSG, warranting further studies of its function in the pathogenesis of human cancers.

Correlation between the status of the p53 gene and survival in patients with stage I non-small cell lung carcinoma.

The association of p53 abnormalities with the prognosis of patients with non-small cell lung carcinoma (NSCLC) has been extensively investigated to date, however, this association is still controversial. Therefore, we investigated the prognostic significance of p53 mutations through exons 2 to 11 and p53 protein expression in 103 cases of stage I NSCLC. p53 mutations were detected in 49 of 103 (48%) tumors. Two separate mutations were detected in four tumors giving a total of 53 unique mutations in 49 tumors. Ten (19%) of mutations occurred outside exons 5-8. Positive immunohistochemical staining of p53 protein was detected in 41 of 103 (40%) tumors. The concordance rate between mutations and protein overexpression was only 69%. p53 mutations, but not expression, were significantly associated with a shortened survival of patients (P<0.001). Furthermore, we investigated the correlation between the types of p53 mutations and prognosis. p53 missense mutations rather than null mutations were associated with poor prognosis (P < 0.001 in missense mutations and P=0.243 in null mutations). These results indicated that p53 mutations, in particular missense mutations, rather than p53 expression could be a useful molecular marker for the prognosis of patients with surgically resected stage I NSCLC.

Benefit of bilateral over single internal mammary artery grafts for multiple coronary artery bypass grafting.

BACKGROUND: The aim of this study was to evaluate the performance of bilateral internal mammary artery (BIMA) grafts in isolated CABG. METHODS AND RESULTS: Beginning in April 1985, elective primary multiple CABG for multivessel disease was performed in 1131 patients. The early and late results of 688 patients who received single internal mammary artery (SIMA) grafts and 443 patients who received BIMA grafts were compared (median follow-up, 6.15 years). Hospital mortality was not significantly different in the SIMA (0.9%) and BIMA (0.9%) groups. Graft patency was 97.3% in the BIMA group and 94.3% in the SIMA group (P<0.0001). The 7-year repeated CABG-free rate was significantly higher in the BIMA group (P=0.026). The 7-year new myocardial infarction-free rate in all patients tended to be higher in the BIMA group (P=0.06). The hazard ratio for all death or repeated CABG in patients with ejection fractions >0.4 and age <71 years was lower in the BIMA group (P=0.0499). CONCLUSIONS: Our data suggest that the use of BIMA grafts in patients with in situ coronary artery anastomoses achieves a significantly higher repeated CABG-free rate in all patients compared with the use of SIMA.

Coronary artery bypass with only in situ bilateral internal thoracic arteries and right gastroepiploic artery.

BACKGROUND: With the rapid advance of catheter intervention, the direction taken by surgeons is not only to make conventional CABG less invasive but also to pursue better long-term results by using more arterial conduits. METHODS AND RESULTS: Between July 1989 and April 2000, 239 patients (218 men, 21 women) with a mean age of 59.7 (range 39 to 79) years underwent CABG with exclusive use of both internal thoracic arteries (ITAs) and the right gastroepiploic artery (RGEA). ITA grafts were harvested by using the skeletonization technique. Most patients (96%) had either triple-vessel or left main disease. Fifty percent of the patients were diabetic, and 16 were being treated with insulin. The left ventricular ejection fraction was

Phenotypic alterations of small cell lung carcinoma induced by different levels of wild-type p53 expression.

p53 induces both growth arrest and apoptosis in cancer cells. To clarify whether the level of p53 expression determines the response of small cell lung carcinoma (SCLC) cells, we assessed the effect of various p53 levels on a p53-null SCLC cell line, N417, using a tetracycline (Tc)-regulated inducible p53 expression system. Apoptosis was induced in SCLC cells with high p53 expression. Although low levels of p53 induced G1 arrest accompanied by p21 expression, cells with G1 arrest seemed to undergo apoptosis after further cultivation. Expression of exogenous p21 induced G1 arrest but not apoptosis in SCLC cells, suggesting that p53-mediated G1 arrest was induced through p21 expression. Moreover, high level of p53 expression down-regulated Bcl-2 expression in SCLC cells, while Bax was consistently expressed irrespective to the level of p53 expression. These results suggest that p53-mediated apoptosis and G1 arrest depend on level of p53 expression in SCLC cells and that the relative dominancy of Bax to Bcl-2 is involved in the induction of apoptosis by high level of p53 expression.

Prognostic significance of allelic imbalances on chromosome 9p in stage I non-small cell lung carcinoma.

Loss of heterozygosity (LOH) on chromosomes 2q, 9p, 18q, and 22q frequently occurs in advanced non-small cell lung carcinoma (NSCLC). The association of p53 mutations with prognosis is still unclear in NSCLC. Therefore, we investigated the prognostic significance of allelic imbalances (AI) on these chromosomes and p53 mutations in 108 cases of stage I NSCLC by PCR amplification of polymorphic dinucleotide repeat-containing sequences and PCR-single strand conformation polymorphism analysis. AI on 2q, 9p, 18q, and 22q was detected in 22, 38, 29, and 15% of cases, respectively, whereas p53 was mutated in 41% of stage I NSCLC. AI on 9p and 22q and p53 mutations were significantly associated with shortened survival of the patients (P = 0.010, 0.024, and 0.022, respectively). Although gender and smoking history showed more significant associations with prognosis than other clinicopathological and molecular parameters, independent prognostic significance for AI on 9p was observed (P = 0.002) in male patients with a positive smoking history. These results indicate that clinical aggressiveness of early-stage NSCLC can be partly defined by the presence of AI on chromosome 9p in cancer cells, and that AI on 9p could be a clinically useful prognostic indicator for early-stage NSCLC patients.

Efficacy of platinum combination chemotherapy after first-line gefitinib treatment in non-small cell lung cancer patients harboring sensitive EGFR mutations.

PURPOSE: Gefitinib is an effective first-line chemotherapy for advanced non-small cell lung cancer (NSCLC) patients harboring sensitive EGFR mutations. However, whether second-line platinum combination chemotherapy after first-line gefitinib treatment shows similar effects to first-line platinum combination chemotherapy in these patients remains unclear. Therefore, we here aimed to investigate the efficacy of platinum combination chemotherapy after first-line gefitinib treatment in NSCLC patients harboring sensitive EGFR mutations. METHODS/PATIENTS: We retrospectively evaluated the clinical effects of second-line platinum combination chemotherapy after first-line gefitinib treatment in NSCLC patients harboring sensitive EGFR mutations (exon 19 deletion or exon 21 L858R mutation) at five institutions. All patients were initially treated with gefitinib (250 mg/day) followed by platinum combination chemotherapy as second-line chemotherapy. RESULTS: Between January 2006 and December 2012, 42 patients [8 men, 34 women; median age, 63 years (range 39-75 years)] were enrolled. The overall response rate, disease control rate, and median progression-free survival (PFS) were 26.2, 61.9%, and 5.1 months, respectively, after the second-line treatment. The corresponding values for first-line gefitinib treatment were 69.0, 95.2%, and 11.1 months, respectively. Moreover, second-line platinum combination chemotherapy with pemetrexed or bevacizumab-containing regimens was independently associated with improved PFS. CONCLUSIONS: Second-line platinum combination chemotherapy after first-line gefitinib treatment in NSCLC patients harboring sensitive EGFR mutations was effective and showed equivalent outcomes to first-line platinum combination chemotherapy. After failure of first-line gefitinib therapy, second-line platinum combination chemotherapy with pemetrexed or bevacizumab might result in improved PFS.

Comprehensive analysis of p53 gene mutation characteristics in lung carcinoma with special reference to histological subtypes.

To date, the characteristics of p53 gene mutations in lung cancer have been extensively investigated. However, current estimates of p53 alterations are inaccurate, since most investigators have limited their analyses to exons 5 to 8 of the p53 gene. We examined 52 lung carcinoma cell lines and 106 primary non-small cell lung carcinomas (NSCLC) for mutations in the entire coding region of the p53 gene, from exons 2 to 11. High resolution single strand conformation polymorphism analysis was performed using a modified electrophoretic apparatus with a high concentration gel (14%) and accurate temperature control. The prevalence of mutations was high (more than 80%) in both small cell lung carcinoma (SCLC) (15 of 18) and NSCLC cell lines (28 of 34), and 9 of 45 mutations (20%) were detected outside the region of exons 5 to 8. The frequency of the mutations in primary NSCLC was 48% (51 of 106) and was significantly different (p=0.01) between adenocarcinoma (39%) and squamous cell carcinoma (67%). A-->G transitions (14%, 6 of 43 cases) as well as G-->T transversions (26%, 11 of 43 cases) were frequently detected with significant strand bias in smoking patients, suggesting that carcinogens causing these mutations are involved in smoking associated lung carcinogenesis.

A comparative analysis of left ventriculography and root aortography for estimating aortic annular size.

This study was undertaken to compare the usefulness of left ventriculography versus root aortography as a means of assessing the aortic annular size in 75 patients with a narrow aortic anulus. These patients were divided into two groups: Group I consisted of 57 patients undergoing standard aortic valve replacement with a 21 mm prosthesis and Group II consisted of 18 patients undergoing modified aortic valve replacement with the aid of an anulus-enlarging procedure or an apico-aortic conduit. In Group I, left ventriculography gave 23.2 +/- 1.8 mm (mean +/- standard deviation), whereas the aortography method showed 22.4 +/- 2.7 mm (p less than 0.05). Those values of 20 mm or less were regarded as imperfect measurements; inaccurate results were more frequent in the aortography method (16 cases; 28%) than in the left ventriculography method (only two cases; 3.5%), with significant difference (p less than 0.025%). In Group II, there was no significant difference in respective values determined by the two different methods; 18.7 +/- 3.0 mm, with a range from 13 to 23 mm in the left ventriculography method, and 19.9 +/- 3.1 mm, with a range from 14 to 24 mm, in the aortography method (p greater than 0.2). Imperfect measurement by the aortography method tended to occur when the cusp base was severely deformed. The results indicated that left ventriculography was more reliable than root aortography for estimating the size of the aortic anulus.

Rapid endothelialization of vascular prostheses by seeding autologous venous tissue fragments.

A method was developed to obtain rapid endothelialization of a fabric vascular prosthesis by seeding autologous venous tissue fragments into its wall. In an animal study, complete endothelialization was observed in the entire inner surface of the prosthesis within 2 weeks after implantation. A piece of peripheral vein was minced with scissors and then stirred into saline to create a tissue suspension. This suspension was enmeshed into the wall of a highly porous fabric vascular prosthesis by repeated pressurized injections with a syringe. The prostheses (7 mm inside diameter and 5.7 cm in length), seeded with tissue fragments, were implanted into the descending thoracic aorta of 25 dogs, and they were removed from 1 hour to 2 months after implantation. Twenty-five prostheses, preclotted with fresh blood, were used as control prostheses. In the seeded graft, a thin fibrin layer covered the inner surface just after implantation, but countless numbers of endothelial cells migrated from the fragments and came up to the luminal surface like multiple "mushrooms" under the fibrin layer. Smooth muscle cells made multiple layers underneath the endothelial cell layer. The healing proceeded equally at every part. By this active migration and proliferation, the inner surface was completely healed within 2 weeks.

Acceleration of neointima formation in vascular prostheses by transplantation of autologous venous tissue fragments. Application to small-diameter grafts.

We have previously demonstrated rapid and complete endothelialization in synthetic fabric vascular prostheses that have been pretreated with autologous venous tissue fragments. However, significant thrombogenicity has been a major problem when this method has been applied to small-diameter grafts. By masking the positively charged collagen fibrils in the tissue fragments with negatively charged heparin, we were able to overcome this problem. A canine jugular vein was resected, minced into tissue fragments, and suspended. This mixture was sieved through the wall of a highly porous vascular prosthesis with a water porosity value of 4,000 ml/cm2 per minute by pressurized injection, which caused the tissue fragments to be trapped in the graft wall. Tissue-fragmented grafts (7 mm inside diameter, 5.7 cm long) were implanted into the thoracic aorta of 35 dogs. In addition, tissue-fragmented grafts of small diameter (4 mm inside diameter, 3.5 cm long) were pretreated with heparin and implanted into the carotid arteries of 16 dogs (32 grafts). Preclotted grafts without tissue fragmentation were implanted into the thoracic aorta (25 dogs) and carotid arteries (6 dogs, 12 grafts) as controls. Grafts were explanted from 1 to 495 days after implantation. New arterial wall formation was complete throughout the tissue-fragmented grafts within 2 weeks; however, in the control grafts, neointima formation was limited to the anastomotic sites even after 2 months. Twenty small-caliber tissue-fragmented grafts that were pretreated with heparin in the carotid position were patent, but all the control grafts were occluded within 1 week. These results demonstrate that neointima formation can be enhanced in synthetic fabric prostheses; furthermore, long-term patency of vascular grafts of small caliber is possible in dogs with this tissue-fragmentation technique.

Reconstruction of the left ventricle in a patient with cardiac hemangioma at the apex.

Cardiac hemangiomas in the left ventricle are extremely rare. A 34-year-old woman, without symptoms, with a diagnosis of cardiac tumor at the apex of the left ventricle was referred to us. The tumor was surgically resected, and the diagnosis was hemangioma. The Jatene technique, originally introduced for left ventricular aneurysmectomy was excellent for repair after resection of a cardiac tumor at the apex.

Heart valve operation in acromegaly.

BACKGROUND: Intractable congestive heart failure is known as a serious complication of acromegaly, but valvular heart disease rarely occurs in acromegalic patients. We experienced 5 surgical cases of valvular heart disease associated with acromegaly. We describe the features of those cases in this report. METHODS: The patient characteristics and operative and pathologic findings were retrospectively studied. RESULTS: There were 4 men and 1 women. Age at operation was 59 +/- 5.5 years. Cardiac lesions consisted of 1 case of aortic regurgitation associated with mitral regurgitation, 1 of aortic regurgitation, and 3 of mitral regurgitation. Operative procedures consisted of 1 double valve replacement (aortic and mitral valve replacement), 1 aortic valve replacement, and 3 mitral valve replacements. The causes of aortic valvular regurgitation were aortic valvular degeneration and aortic annular dilatation. The causes of mitral regurgitation were chordal rupture and mitral valvular degeneration. Histopathologic examination of the excised valves showed mucopolysaccharide deposits and myxomatous degeneration of the leaflets. The myocardium showed fibrosis of interstitial spaces and endocardium, and disarrangement of muscle fibers. CONCLUSIONS: We report 5 successful surgical cases of valvular heart disease associated with acromegaly. Earlier operation is recommended for such cases because of acromegalic cardiomyopathy.