Using a newly developed assay of telomerase reverse transcriptase (hTERT) mRNA in serum by real-time RT-PCR, we previously reported this assay to be superior to other tumor markers for hepatoma. In this study, we aimed to clarify its clinical significance as a biomarker for lung cancer. In 112 patients with lung tumor and 80 individuals without cancer, we measured serum hTERT mRNA and epidermal growth factor receptor (EGFR) mRNA levels, using a quantitative one-step real-time RT-PCR assay. We examined its sensitivity and specificity in lung cancer diagnosis, its clinical significance in comparison with other tumor markers, and its correlation with the clinical parameters using multivariate analyses and correlation relative tests. The copy number of serum hTERT mRNA was independently correlated with tumor size, tumor number, presence of metastasis and recurrence, and smoking (all P < 0.05). EGFR mRNA correlated with tumor number and clinical stage (both P < 0.05). The sensitivity and specificity in lung cancer diagnosis were 89.0% and 72.7% for hTERT mRNA, and 71.3% and 80.0% for EGFR mRNA, respectively. hTERT mRNA was superior to other tumor markers in lung cancer diagnosis. For both mRNAs, serum levels were significantly correlated with levels in lung cancer tissues (both P < 0.05). The copy number of hTERT mRNA significantly decreased after the surgical treatment. The data suggest that hTERT mRNA, especially when combined with EGFR mRNA, is a novel and excellent biomarker for pulmonary malignancies to diagnose and assess the clinical stage. (Cancer Sci 2006; 97: 1366-1373) L ung cancer is the leading cause of malignancy-related mortality (1) with little change in the survival rates over the past two decades.(2) NSCLC now accounts for about three-quarters of all cases of lung cancer (3) and most patients continue to die of progressive metastatic disease despite the development of new therapeutic strategies and advances in surgical treatment. Serum tumor markers are non-invasive diagnostic tools for malignant tumors and they are commonly used for the screening of cancer and as an indicator of the treatment effect. In SCLC, neuronspecific enolase and pro-gastrin-releasing peptide are effective markers. In NSCLC, CEA, SCCA, and CYFRA 21-1 are commonly used for screening, and at least one marker among CEA, SCCA and CYFRA is positive in approximately 70% of patients with NSCLC.(4) According to the histological category, the positive rates of CEA and CYFRA are high in patients with ADC, and the positive rates of CYFRA and SCCA are high in patients with SCC. Although the standard diagnostic procedures such as X-ray examinations, conventional tumor markers, and bronchial lavage are important for the detection of lung cancer, they are not still sensitive enough to detect lung cancer at an early clinical stage.Tyrosine kinase activity of EGFR promotes tumor cell proliferation, cell survival, angiogenesis, invasion, and metastasis, and its specific inhibition by gefitinib, a synthetic anilinoquinazoline, has been demonstr...

Purpose: We previously reported the usefulness of a qualified highly sensitive detection method for human telomerase reverse transcriptase (hTERT) mRNA in serum with 89.7% sensitivity for hepatocellular carcinoma (HCC). In this study, we developed a quantitative detection method for serum hTERT mRNA and examined the clinical significance in HCC diagnosis. Experimental Background: In 64 patients with HCC, 20 with liver cirrhosis, 20 with chronic hepatitis, and 50 healthy individuals, we measured serum hTERT mRNA by using the newly developed real-time quantitative reverse transcription-PCR with SYBR Green I. We examined its sensitivity and specificity in HCC diagnosis, clinical significance in comparison with other tumor markers, and its correlations with the clinical variables by using multivariate analyses. Results: Serum hTERT mRNA showed higher values in patients with HCC than those with chronic liver diseases. hTERT mRNA expression was shown to be independently correlated with clinical variables such as tumor size, number, and degree of differentiation (P < 0.001, each). The sensitivity/specificity of hTERT mRNA and a-fetoprotein (AFP) mRNA in HCC diagnosis were 88.2%/70.0% for hTERT and 71.6%/67.5% for AFP, respectively. hTERT mRNA proved to be superior to AFP mRNA, AFP, and des-g-carboxy prothrombin in HCC diagnosis. Furthermore, hTERT mRNA in serum was associated with that in HCC tissue. Conclusions:The usefulness of hTERT mRNA expression in HCC diagnosis and its superiority to conventional tumor markers were shown. Therefore, serum hTERT mRNA is a novel and available marker for HCC diagnosis.

Background: We attempted to clone candidate genes on 10p14-15 which may regulate hTERT expression, through exon trapping using 3 BAC clones covering the region. After obtaining 20 exons, we examined the function of RGM249 (RGM: RNA gene for miRNAs) we cloned from primary cultured human hepatocytes and hepatoma cell lines. We confirmed approximately 20 bp products digested by Dicer, and investigated the function of this cloned gene and its involvement in hTERT expression by transfecting the hepatoma cell lines with full-length dsRNA, gene-specific designed siRNA, and shRNA-generating plasmid.

Human telomerase reverse transcriptase (hTERT) and epidermal growth factor receptor (EGFR) play an important role in many cancers including gynecological cancers. We previously reported the usefulness of a quantitative highly sensitive detection method for hTERT mRNA in the serum of cancer patients. By this method, we attempted to elucidate the diagnostic evaluation of serum hTERT mRNA for gynecologic malignancies. In 174 female patients with gynecological lesions (47 with ovarian lesions, 63 with uterine lesions, 2 with malignancies in other gynecological lesions, and 62 benign lesions) and 20 healthy individuals, we measured serum hTERT mRNA and EGFR mRNA by using the newly developed real-time quantitative RT-PCR. We examined their sensitivity and specificity in cancer diagnosis, clinical significance in comparison with conventional tumor markers, and their correlations with the clinical parameters by using multivariate analyses. Serum hTERT mRNA showed higher values in patients with gynecologic cancers than in those with benign diseases and healthy individuals. The hTERT mRNA level independently correlated with the presence of cancers (P=0.004 for both ovarian and uterine cancer) and clinical stage (P<0.001). The sensitivity and specificity of hTERT mRNA in cancer diagnosis was 74.4% and 74.1%, respectively. The hTERT mRNA level showed a significant correlation with CA125 by Pearson's relative test (P=0.035) and with histological findings in ovarian cancer by the Friedman test (P<0.004). EGFR mRNA did not display any differences between the diseases. hTERT mRNA is useful for diagnosing gynecologic cancer and is superior to conventional tumor markers. Therefore, serum hTERT mRNA is a novel and available biomarker for gynecologic malignancies.

The human noncoding RNA gene RGM249 has been shown to regulate the degree of cancer cell differentiation. In this study, we investigated the effects of 3 microRNA-like molecules digested from RGM249 on the loss of malignant properties in cancer cells in immunodeficient KSN/Slc mice. We utilized small interfering RNAs (siRNAs) alone or in combination with a cationized drug delivery system (DDS) consisting of atelocollagen or gelatin hydrogel microspheres. The results demonstrated growth inhibition and apoptosis and the inhibition of both neovascularization and metastasis, indicating that the DDSs effectively infiltrated the majority of tumor cells in vivo. Systemic administration of the 3 siRNAs inhibited the metastatic ability of malignant cells. Cotransfection of these siRNAs exerted a regulatory effect upon the genes involved in differentiation, pluripotency, and proliferation in cancer cells. These results suggest that RGM249-derived oligonucleotides may be involved in the regulation of metastasis, proliferation, and differentiation in vivo, and that the tested siRNAs may therefore represent a new anticancer therapeutic approach.