Masashi Nakayama

Global DNA hypomethylation in intratubular germ cell neoplasia and seminoma, but not in nonseminomatous male germ cell tumors

Alterations in methylation of CpG dinucleotides at the 5 position of deoxycytidine residues (5mC) are a hallmark of cancer cells, including testicular germ cell tumors. Virtually all testicular germ cell tumors are believed to be derived from intratubular germ cell neoplasia unclassified (IGCNU), which is thought to arise from primordial germ cells. Prior studies revealed that seminomas contain reduced levels of global DNA methylation as compared with nonseminomatous germ cell tumors. Smiraglia et al have proposed a model whereby seminomas arise from IGCNU cells derived from primordial germ cells that have undergone 5mC erasure, and nonseminomas arise from IGCNU cells derived from primordial germ cells that have already undergone de novo methylation after the original erasure of methylation and contain normal 5mC levels. Yet the methylation status of IGCNU has not been determined previously. We used immunohistochemical staining against 5mC to evaluate global methylation in IGCNU and associated invasive testicular germ cell tumors. Strikingly, staining for 5mC was undetectable (or markedly reduced) in the majority of IGCNU and seminomas, yet there was robust staining in nonseminomatous germ cell tumors. The lack of staining for 5mC in IGCNU and seminomas was also found in mixed germ cell tumors containing both seminomatous and nonseminomatous components. Lack of 5mC staining was not related to a lack of the maintenance methyltransferase (DNA methyltransferase 1) protein. We conclude that testicular germ cell tumors are derived in most cases from IGCNU cells that have undergone developmentally programmed 5mC erasure and that the degree of subsequent de novo methylation is most closely related to the differentiation state of the neoplastic cells. That is, IGCNU cells and seminoma cells remain unmethylated, whereas all other histological types appear to arise after de novo methylation.

Infiltration of tumour‐associated macrophages in prostate biopsy specimens is predictive of disease progression after hormonal therapy for prostate cancer

Study Type – Prognostic (case series)

Sesquiterpene lactone parthenolide suppresses tumor growth in a xenograft model of renal cell carcinoma by inhibiting the activation of NF-κB

The transcription factor nuclear factor‐κB (NF‐κB) has been shown to be constitutively activated in various human malignancies, including leukemia, lymphoma and a number of solid tumors. NF‐κB regulates the transcriptional of genes important for tumor invasion, metastasis and chemoresistance. The sesquiterpene lactone parthenolide, an inhibition of NF‐κB, has been used conventionally to treat migraines and inflammation. In this study, renal cancer cell lines OUR‐10 and ACHN were used for in vitro experiments to evaluate growth‐inhibitory effects of parthenolide. An OUR‐10 xenograft model in nude mice was also used to investigate the in vivo growth‐inhibitory effects of parthenolide. Apoptosis in response to treatment of OUR‐10 cells with parthenolide was confirmed. Localization of NF‐κB in response to parthenolide treatment was examined of by immunofluorostaining of OUR‐10 cells with antibody against NF‐κB p65 and by Western blot analysis of OUR‐10 cell and tumor nuclear and cytosol fraction. Parthenolide effectively inhibited proliferation of cultured OUR‐10 cells and triggered apoptosis in vitro. Subcutaneous injection or oral administration of parthenolide showed significant tumor growth inhibition in the xenograft model via decreased production of interleukin‐8 (IL‐8) or vascular endothelial growth factor (VEGF). Immunohistochemistry and Western blot analysis showed decreased nuclear localization of NF‐κB and phosphorylated NF‐κB protein and subsequently expression of MMP‐9, Bcl‐xL and Cox‐2 in response to parthenolide treatment. These results indicate that parthenolide is a useful in the treatment of renal cell carcinoma and acts via inhibition of NF‐κB.

Increased Infiltration of Tumor Associated Macrophages is Associated With Poor Prognosis of Bladder Carcinoma In Situ After Intravesical Bacillus Calmette-Guerin Instillation

PURPOSE Tumor associated macrophages can regulate the growth of various cancers positively or negatively. Intravesical bacillus Calmette-Guerin instillation is now gold standard treatment for bladder carcinoma in situ. We investigated the correlation between tumor associated macrophages infiltrating bladder carcinoma in situ and the response to intravesical bacillus Calmette-Guerin therapy. MATERIALS AND METHODS We examined paraffin embedded tissues from 41 patients with bladder carcinoma in situ who received intravesical bacillus Calmette-Guerin therapy. Tumor associated macrophages were immunohistochemically stained by anti-CD68 monoclonal antibody. RESULTS The median number of tumor associated macrophages infiltrating among cancer cells and the number in the lamina propria were 4 and 24, respectively. Recurrent carcinoma in situ was found in 4.8% of cases with a lower cancer cell tumor associated macrophage count but in 47.6% of those with a higher cancer cell tumor associated macrophage count (less than 4 vs 4 or greater). Recurrence was found in 31.8% of patients with a lower lamina propria tumor associated macrophage count but in 21.1% of those with a higher lamina propria tumor associated macrophage count (less than 25 vs 25 or greater). The median ratio of tumor associated macrophages among cancer cells vs in the lamina propria was 0.2. Recurrence-free survival was significantly better in patients with a lower cancer cell tumor associated macrophage count (p = 0.0002). Those with a lower cancer cell-to-lamina propria tumor associated macrophage ratio had a higher recurrence-free rate (p <0.0001). Multivariate analysis revealed that the cancer cell tumor associated macrophage count and the cancer cell-to-lamina propria tumor associated macrophage ratio can be prognostic factors for bladder carcinoma in situ. CONCLUSIONS The count of tumor associated macrophages infiltrating the cancer area is useful for predicting the response of bladder carcinoma in situ to intravesical bacillus Calmette-Guerin instillation before treatment initiation.

Shared TP53 Gene Mutation in Morphologically and Phenotypically Distinct Concurrent Primary Small Cell Neuroendocrine Carcinoma and Adenocarcinoma of the Prostate

Small cell carcinoma of the prostate is an uncommon neoplasm, the origin of which has been controversial. To address this, we performed transcriptome profiling and TP53 sequencing of concurrent small cell and prostatic adenocarcinoma to determine the relationship between these entities.

Excision Repair Cross-Complementing Group 1 May Predict the Efficacy of Chemoradiation Therapy for Muscle-Invasive Bladder Cancer

Purpose: Chemoradiation therapy (CRT) is now widely recognized as bladder-preserving therapy for muscle-invasive bladder cancer (MIBC). However, some patients who fail CRT may miss the chance to be cured by cystectomy. Therefore, it is important to select patients with MIBC who are expected to have a good response to CRT. Several reports indicate that the excision repair cross-complementing group 1 (ERCC1) gene is associated with resistance to cisplatin and radiation therapy. In this study, we examined the correlation between ERCC1 and CRT in vitro and in vivo in bladder cancer. Experimental Design: Bladder cancer cell lines T24, 5637, Cl8-2 (multidrug-resistant subline of T24), and CDDP10-3 (cisplatin-resistant subline of T24) were used for in vitro assays to measure ERCC1 expression level and growth inhibition with cisplatin or ionizing radiation (IR). We then examined by immunohistochemistry that whether ERCC1 nuclear staining correlates with the efficacy of CRT using cisplatin in 22 patients with MIBC. Results: Cl8-2 cells expressed ERCC1 mRNA 5.96-fold higher than did T24. Cl8-2 and CDDP10-3 were more resistant to cisplatin or IR than was T24. Resistance to IR, but not to cisplatin, was removed by suppressing ERCC1 using siRNA in both Cl8-2 and CDDP10-3 cells. In immunohistochemistry with ERCC1, 6 of 8 positive cases did not have complete response to CRT, whereas 12 of 14 negative cases had complete response. Sensitivity and specificity were 75% and 85.7%, respectively (P = 0.008). Conclusion: Although further study is needed, ERCC1 expression level may predict the efficacy of CRT for MIBC. Clin Cancer Res; 17(8); 2561–9. ©2010 AACR.

Possible correlation between polymorphism in the tumor necrosis factor-beta gene and the clinicopathological features of bladder cancer in Japanese patients

Objectives:  In a variety of cancers, several polymorphisms of the tumor necrosis factor (TNF) genes have been reported to result in different clinical outcomes. We investigated whether a polymorphism of the TNF gene is associated with a susceptibility to bladder cancer and its disease status.

SERPINE2 is a possible candidate promotor for lymph node metastasis in testicular cancer

Testicular germ cell tumors (TGCTs) commonly metastasize to the lymph node or lung. However, it remains unclear which genes are associated with TGCT metastasis. The aim of this study was to identify gene(s) that promoted human TGCT metastasis. We intraperitoneally administered conditioned medium (CM) from JKT-1, a cell-line from a human testicular seminoma, or JKT-HM, a JKT-1 cell sub-line with high metastatic potential, into mice with JKT-1 xenografts. Administration of CM from JKT-HM significantly promoted lymph node metastasis. A cDNA microarray analysis showed that JKT-HM cells highly expressed the Serpine peptidase inhibitor, clade E, member 2 (SERPINE2), which encodes a secreted protein. Administration of CM from SERPINE2-silenced JKT-HM cells inhibited lymph node metastasis in the xenograft model, compared with administration of CM from JKT-HM cells. There was no significant difference in xenograft volume. Moreover, administration of CM from SERPINE2-over-expressing JKT-1 was likely to promote lymph node metastasis in the xenograft model. There was no difference in the in vitro proliferation or migration of JKT-1 cells cultured with CM from JKT-HM cells, compared to that with CM from JKT-1. There was no promotion of proliferation or lymphangiogenesis in the xenografts, as measured by Ki-67 and LYVE-1 immunohistochemistry, respectively. Although we could not clarify how SERPINE2 promoted lymph node metastasis, it may be a promoter in the development of lymph node metastasis in the human seminoma cells in a mouse xenograft model.

Brain metastases from testicular germ cell tumors: A retrospective analysis

Objectives:  To review our series of testicular germ cell tumors with brain metastases and to establish an optimal treatment strategy for them.

GSTP1 CPG ISLAND HYPERMETHYLATION AS A MOLECULAR BIOMARKER FOR PROSTATE CANCER

ZusammenfassungHintergrundDas Prostatakarzinom (PCA) ist das häufigste Karzinom der männlichen Bevölkerung in Europa und Nordamerika. Trotz der hohen Prävalenz ist der molekulare Ablauf der Entstehung und der Progression nur teilweise bekannt. In zahlreichen Untersuchungen wurden die molekulargenetischen Alterationen in der Pathogenese des Prostatakarzinoms bearbeitet. Die CpG-Insel-Hypermethylierung des Glutathion-S-tranferase-Gens (GSTP1) ist eine dieser charakteristischen Veränderung in der Karzinogenese des Prostatakarzinoms.Material und MethodenWir haben die Bedeutung der GSTP1-CpG-Insel-Hypermethylierung in der Karzinogenese des Prostatakarzinoms untersucht und auf die klinische Anwendung hin geprüft.ErgebnisseIn den Untersuchungen konnte die GSTP1-CpG-Insel-Hypermethylierung bei mehr als 90% der Prostatakarzinome festgestellt werden. Es gelang der Nachweis in verschiedenen Körperflüssigkeiten (Blut, Urin, Ejakulat, Prostatasekret) und bei im Rahmen einer radikalen Prostatektomie entfernten Lymphknoten; eine Unterscheidung zwischen normalem Prostatagewebe, der benignen Prostatahyperplasie, Vorläuferstadien des Prostatakarzinoms und dem Prostatakarzinom ist durch die modernen, molekulargenetischen Untersuchungstechniken möglich.SchlussfolgerungenMit dem Nachweis der GSTP1-CpG-Insel-Hypermethylierung steht ein molekularer Test zur Verfügung, der das Screening und die Diagnostik des Prostatakarzinoms verbessert. Ein spezifisches Methylierungsmuster des PCA könnte als molekulares Staging Aussagen über die Prognose des PCA leisten. Zur Bestätigung der vielversprechenden, aber noch experimentellen Ergebnisse sind allerdings große prospektive Studien erforderlich.AbstractBackground Prostate cancer is the most commonly diagnosed cancer in men in Europe and North America. Despite its high prevalence, the molecular mechanism of its underlying development and progression is poorly understood. Many studies have revealed multiple molecular alterations during prostate cancer carcinogenesis. GSTP1 CpG island hypermethylation is one of the molecular changes that occur during carcinogenesis.MethodsWe evaluated the role of GSTP1 CpG island hypermethylation in prostatic cancers and discussed its possible role as a molecular biomarker of prostate cancer.ResultsStudies haven shown that GSTP1 CpG island hypermethylation is present in about 90% of prostatic carcinomas. The DNA alteration was also detectable in body fluids such as blood, urine, ejaculate, or prostatic secretions. One study showed hypermethylation in histologically unsuspicious lymph nodes in surgical specimens in patients with biochemical PSA (prostate-specific antigen) recurrence. Additionally, it is possible to distinguish between normal prostatic tissue, benign prostatic hyperplasia, and prostate cancer.ConclusionsThe detection of GSTP1 CpG island hypermethylation serves as a molecular marker in prostate cancer screening, detection, and diagnosis. It may even provide information on prostate cancer prognosis. However, prospective trials to evaluate its predictive value are necessary.