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Pulmonary tumor embolism (PTE) is difficult to diagnose before death. We report the case of a 75-year-old man with microscopic PTE of renal cell carcinoma who was diagnosed by surgical lung biopsy. He visited our hospital because of dyspnea on exertion. Chest computed tomography (CT) showed multiple micronodules and ground glass opacities. Steroid therapy was started as therapeutic diagnosis for IgG4-related pulmonary disease. However, he was admitted our hospital due to progressive respiratory failure. Pathological findings of a lung biopsy obtained by video-assisted thoracic surgery showed PTE of renal cell carcinoma without embolization of large pulmonary arteries. He received palliative medicine and died four months after the surgical lung biopsy. In cases of multiple micronodules in chest CT findings and worsened respiratory symptoms, PTE should be considered in the differential diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: Non-small cell lung cancer (NSCLC) in never smokers has emerged as a global public health issue. The cause is still unclear, and few studies have focused on the prevalence of human papillomavirus (HPV) in the never smokers. We performed a systematic search of PubMed for articles of HPV infection in human subjects with NSCLC up to September 2012. Although smoking status was not fully reported in all studies, we contacted the authors by e-mail to supplement this information. Differences in the distribution of patients with and without HPV infection were tested with the Chi squared test. We identified 46 eligible articles, including 23 from Asian countries (N =2337 NSCLC cases), 19 from European countries (N =1553) and 4 from North and South America (N =160). The HPV prevalence was 28.1% (95% confidence interval (CI) 26.6–30.3%), 8.4% (95% CI 7.1–9.9%) and 21.3% (95% CI 15.2–28.4%), respectively. Eleven studies from East Asia (N =1110) and 4 from Europe (N =569) provided information on smoking status. The number of never smoker was 392 patients (33.9%) in East Asia and 54 patients (14.8%) in Europe. The HPV prevalence in East Asian countries was similar between never and ever smokers (33.9% vs 39.2%, P =0.080). Based on the literature confirming the presence of HPV in lung cancer in never smokers, the virus plays a role in carcinogenesis in the disease. There were different patterns of HPV prevalence between Asian and European countries in the never smokers as well as in ever smokers. [Copyright &y& Elsevier]

Summary: Cytokeratins (CKs) constitute the largest family of intermediate filament proteins, and are subdivided into type I (CK9–CK23) and type II (CK1–CK8) subclasses. CK19 is expressed in non-small cell lung cancer (NSCLC), and serum CK19 fragment (referred to as CYFRA21-1) is one of the tumor markers used in diagnosing NSCLC. Type I and type II CKs have been shown to form obligate 1:1 heteropolymers, suggesting that dynamic changes must occur in the expression levels of CK pools when one CK is suppressed. However, the absolute levels of CK expression and their dynamic changes have not been fully evaluated. Therefore, we quantitatively determined CK expression levels in NSCLC cell lines, and evaluated the rate of change of CK expression levels after RNA interference targeting of single CKs. In NSCLC cells, type I CK18 and type II CK8 are the dominant CKs, with absolute expression levels of 12–77pmol/106 cells, while the expression patterns of the CKs vary among cell lines. Moderate suppression of a single dominant CK caused downregulation in CKs of the complementary type, and upregulation of other CKs of the same type. In contrast, severe suppression of a single dominant CK caused almost complete suppression of all CKs. In addition, introduction of CK19 led to resistance to CK degradation by CK18 suppression. These data suggest the presence of a critical threshold expression level for a dominant CK and a role for CK19 in the compensation of type I and type II CK pools in NSCLC. [Copyright &y& Elsevier]

Cytokeratin 8 (CK8) is one of the cytoskeletal components and shows caspase-mediated degradation when cells undergo apoptosis. We previously reported that CK8 is highly expressed in non-small cell lung cancer (NSCLC) cell lines and increasing values of serum CK8 are significantly associated with tumor progression in patients with NSCLC. In this investigation, reverse transcriptase-polymerase chain reaction (RT-PCR) analysis in lung cancer cell lines, revealed a shorter PCR product, which differed from the wild-type product of CK8. The nucleotide sequence of the shorter PCR products and genomic DNA for CK8 demonstrated that the shorter product was an aberrantly spliced form of CK8 (AS-CK8) which lacked a caspases cleavage site within the linker lesion in exon 5. The putative protein products predicted by the mRNA of AS-CK8 were demonstrated by Western blotting with monoclonal antibodies for CK8. In addition, AS-CK8 mRNA and its protein products were highly expressed in NSCLC cell lines compared with small-cell lung cancer (SCLC) cell lines. Tissue samples obtained from NSCLC patients also expressed mRNA of AS-CK8. In conclusion, we identified aberrantly spliced CK8 (AS-CK8) which lacked a caspases cleavage site in lung cancer cell lines and primary tumors of NSCLC. AS-CK8 was preferentially expressed in NSCLC, rather than SCLC. These findings lead to speculation that cancer cells expressing AS-CK8 may have a resistance to apoptosis and may perturb keratin network formation. [Copyright &y& Elsevier]

Abstract: Intrapulmonary schwannoma is uncommon and preoperative radiological diagnosis is rare. Described is a schwannoma that developed as a pulmonary hilar nodule in a 38-year-old woman. The nodule showed strong 18F-fluorodeoxyglucose uptake with a maximum standard uptake value of 5.98 on positron emission tomography and had a high apparent diffusion coefficient (2.5×103 mm2/s) on diffusion-weighted magnetic resonance imaging. Combination of these functional imaging techniques warrants further evaluation in radiological diagnosis of intrapulmonary schwannoma. [Copyright &y& Elsevier]