To improve the outcome in newly diagnosed glioblastoma patients with maximal resection, we aimed to evaluate the efficacy and safety of implantation of carmustine wafers (CWs), radiation concomitant with temozolomide and bevacizumab, and maintenance chemotherapy with six cycles of temozolomide and bevacizumab. This prospective phase II study enrolled glioblastoma patients considered candidates for complete resection (> 90
Expression of PKM2, which diverts glucose-derived carbon from catabolic to biosynthetic pathways, is a hallmark of cancer. However, PKM2 function in tumorigenesis remains controversial. Here, we show that, when expressed rather than PKM2, the PKM isoform PKM1 exhibits a tumor-promoting function in KRAS(G12D)-induced or carcinogen-initiated mouse models or in some human cancers. Analysis of Pkm mutant mouse lines expressing specific PKM isoforms established that PKM1 boosts tumor growth cell intrinsically. PKM1 activated glucose catabolism and stimulated autophagy/mitophagy, favoring malignancy. Importantly, we observed that pulmonary neuroendocrine tumors (NETs), including small-cell lung cancer (SCLC), express PKM1, and that PKM1 expression is required for SCLC cell proliferation. Our findings provide a rationale for targeting PKM1 therapeutically in certain cancer subtypes, including pulmonary NETs.
Background: Glioblastoma multiforme is one of the most malignant tumors of the human central nervous system characterized by high degree of invasiveness. Focusing on this invasive nature, we investigated whether ganglioside-specific sialidase NEU3 might be involved, because gangliosides are major components of brain tissues, and cell surface sialic acids, as target residues of sialidase catalysis, are thought to be closely related to cell invasion. Methods: NEU3 mRNA levels of human glioblastoma specimens were evaluated by quantitative RT-PCR. Human glioblastoma cell lines, U251, A172, and T98G were used for cell invasion and migration by transwell and cell scratching assay. The molecules involved in the signaling cascade were investigated by western blot and immunofluorescent microscopy. Results: NEU3 expression was down-regulated in human glioblastoma specimens. In the human glioblastoma cell lines, NEU3 overexpression reduced invasion and migration by promoting the assembly of focal adhesions through reduced calpain-dependent proteolysis, but NEU3 silencing resulted in accelerating cell invasion via disassembly of focal adhesions. In NEU3-silenced cells, elevation of calpain activity and GM3 accumulation were observed, as results of reduced sialidase hydrolysis, localization of calpain and GM3 at the cell lamellipodium being demonstrated by immunofluorescence microscopy. Conclusion: Sialidase NEU3 was found to exert a great influence on cell invasion in regulation of calpain activity and focal adhesion disassembly and consequent invasive potential of glioblastoma cells.
Introduction: Sixty years since its introduction, 5-FU still forms the core of chemotherapy regimens for many types of malignancies. 5-FU is a time-dependent drug but is rapidly degraded in plasma by dihydropyrimidine dehydrogenase (DPD). Although originally developed in an intravenous form, 5-FU oral prodrugs were developed with the goal of improving efficacy and minimizing toxicity as well as to capitalize on the advantages of oral drug administration. The inactive 5-FU prodrug is gradually converted into the active form in the systemic circulation. UFT, S-1, and capecitabine are oral 5-FU prodrugs currently in clinical use. However, the efficacy of 5-FU can be further improved by its combination with DPD inhibitors and biochemical modulators, such as uracil and leucovorin, in addition to modifying administration schedules.Areas covered: We focused on the drug delivery of oral 5-FU prodrugs, their pharmacokinetics, and the development of DPD inhibitors. Since oral 5-FU prodrugs have been formulated into combination drugs, we also discussed the regulatory approval of combination drugs.Expert opinion: Many regimens that include intravenously administered 5-FU can be replaced by oral 5-FU prodrugs. Patients would benefit from development of combination 5-FU oral prodrug formulations and its associated path through the combination drug regulatory approval process.
We previously reported that deficiency in the gene encoding the catalytic subunit of protein phosphatase 6 (Ppp6c) predisposes mouse skin tissue to papilloma formation initiated by DMBA. Here, we demonstrate that Ppp6c loss acts as a tumor promoter in UVB-induced squamous cell carcinogenesis. Following UVB irradiation, mice with Ppp6c-deficient keratinocytes showed a higher incidence of skin squamous cell carcinoma than did control mice. Time course experiments showed that following UVB irradiation, Ppp6c-deficient keratinocytes upregulated expression of p53, PUMA, BAX, and cleaved caspase-3 proteins. UVB-induced tumors in Ppp6c-deficient keratinocytes exhibited a high frequency of both p53- and γH2AX-positive cells, suggestive of DNA damage. Epidemiological and molecular data strongly suggest that UVB from sunlight induces p53 gene mutations in keratinocytes and is the primary causative agent of human skin cancers. Our analysis suggests that PP6 deficiency underlies molecular events that drive outgrowth of initiated keratinocytes harboring UVB-induced mutated p53. Understanding PP6 function in preventing UV-induced tumorigenesis could suggest strategies to prevent and treat this condition.
Ptprz is a receptor-like protein-tyrosine phosphatase (PTP) abundantly expressed in neuronal and glial cells in the central nervous system. To date, several potential substrates of Ptprz such as p190RhoGAP, ErbB4, and Git-1, have been identified. In terms of its biological functions, for example, it was shown that Ptprz regulates differentiation of glial cells, but its role(s) in gliomagenesis remains obscue. In this study, expression of Ptprz mRNA in human glioma samples were analyzed. Ptprz mRNA was up-regulated in glioma when compared to normal brain. We found that the levels of Ptprz mRNA in specimens are correlated with those of Sox-2, a transcription factor associating with glioma stemness. Knock-down of Sox-2 by siRNA decreased Ptprz mRNA of several glioma cell-lines. ChIP analysis showed the physical association of Sox2 to the putative promoter region of Ptprz gene, suggesting that Ptprz is a direct transcriptional target of Sox-2. Up-regulation of Ptprz expression may be a part of transcriptional program elicited by Sox-2, which may contribute to glioma stemness Citation Format: Yoji Yamashita, Nobuhiro Tanuma, Toshihiro Kumabe, Teiji Tominaga, Hiroshi Shima, Ryuichi Katakura. Ptprz gene encoding a transmembrane-type protein phosphatase is up-regulated by Sox-2 in glioma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4103. doi:10.1158/1538-7445.AM2013-4103
Treatment results of glioblastoma (GB) during the last 30 years in Tohoku University were analyzed to identify any improvements in patient outcome in all 332 histologically proven cases of newly diagnosed GB treated consecutively in our department between 1982 and 2011. These 30 years was divided into 5 treatment eras, Group 1 (1982-1988, without preoperative evaluation by magnetic resonance [MR] imaging, n = 46), Group 2 (1989-1996, with preoperative MR imaging, n = 41), Group 3 (1997-1999, additionally underwent intraoperative functional brain mapping and neuronavigation system, n = 38), Group 4 (2000-August 2006, underwent 30 Gy of whole brain radiation followed by 30 Gy of extended local accelerated hyperfractionated radiation therapy, n = 96), and Group 5 (September 2006-2011, adjuvant usage of temozolomide [TMZ], n = 111). Overall survival (OS) was calculated from the date of surgery to the death from any cause. The median survival time/2-year OS/5-year OS of Groups 1 to 5 were 10.7 months/10.9%/0%, 17.3 months/26.2%/6.9%, 15.9 months/23.7%/5.3%, 20.1 months/34.8%/15.5%, and 20.9 months/45.5%/19.7%. The prognosis for patients with GB improved significantly after the introduction of MR imaging. Younger GB, defined as patients aged below 60 years, or total tumor resection with all ages in Group 5 had 5-year 0S of 31.0% and 30.1%, respectively. The prognosis of GB was improved significantly after the introduction of TMZ for elderly GB, recursive partitioning analysis class 5, or totally resected GB. Introduction of MR imaging and TMZ, and total resection of the tumor were important in the improvement of outcome for patients with GB.
Mitogen-activated protein kinase phosphatase 5 (MKP-5)/DUSP10 acts as a phosphatase of stress-activated kinases (JNK and p38), but its activity towards ERK has not been demonstrated. In the present study we observed that MKP-5 interacts with ERK, retains it in the cytoplasm, suppresses its activation and downregulates ERK-dependent transcription. These data suggested a novel MKP-5 function as a scaffold protein for the ERK pathway. We analyzed MKP-5 gene expression in several tumors, and found that it is frequently upregulated in colorectal but not in lung and breast cancer, suggesting its association with the malignant phenotype of colon cancer.
The dual-specificity phosphatase (DUSP) 13 gene encodes two atypical DUSPs, DUSP13B/TMDP and DUSP13A/MDSP using alternative exons. DUSP13B protein is most highly expressed in testis, particularly in spermatocytes and round spermatids of the seminiferous tubules, while that of DUSP13A is restricted to skeletal muscle. Here, we show that DUSP13B inactivated MAPK activation in the order of selectivity, JNK = p38>ERK in cells, while DUSP13A did not show MAPK phosphatase activity. Reporter gene analysis showed that DUSP13B had significant inhibitory effect on AP-1-dependent gene expression, but DUSP13A did not. To our knowledge, DUSP13B is the first identified testis-specific phosphatase that inhibits stress-activated MAPKs. These data suggest an important role for DUSP13B in protection from external stress during spermatogenesis.
Glioblastoma multiforme (GBM), which occurs mostly in individuals over the age of 40, accounts for 12–15% of all primary brain tumors. Patients with GBM have a poor prognosis, even after aggressive upfront therapies. The present study documents that in 5 of these patients, the use of a novel immunotherapeutic approach combined with standard initial therapies resulted in a prolonged survival of over 3 years, which is significantly longer than the expected survival time with conventional therapies. During the course of intravenous cell-transfer immunotherapy, axial magnetic resonance images of the tumor region were monitored for over 5 years. The discontinuation of adoptive transfer regimens resulted in the rapid deterioration of patients with development of Gd-enhancing regions, indicating the initiation of tumor recurrence. Among patients with recurrence, the reinstatement of adoptive cell regimens with more frequent cell-transfers resulted in an apparent re-regression of tumors. Significantly longer survival times were seen in patients receiving transferred autologous lymphoid cells which were expanded in vitro, and which had a considerable proportion of γδT cells. We conclude that immunotherapy, combined with standard treatment, plays a significant role in the management of GBM patients and provides patients with a better prognosis.
Cell division cycle 25 (CDC25) phosphatases are cell-cycle regulatory proteins which are overexpressed in a significant number of human cancers. This study evaluated the role of CDC25 phosphatases in human glioma proliferation. Upregulation of CDC25A was observed in human glioma specimens and human glioma cell lines. Comparison of expression levels of CDC25A and CDC25B messenger ribonucleic acid (RNA) to Ki-67 labeling index in glioma tissues found that Ki-67 labeling index was significantly correlated with the expression of CDC25A, but not with that of CDC25B. Depletion of CDC25A by small interfering RNA and inhibition of CDC25 suppressed cell proliferation and induced apoptosis in glioma cell lines, indicating that CDC25A is a potential target for the development of new therapy for glioma.
A 43-year-old female presented with idiopathic hypereosinophilic syndrome (HES) manifesting as an intraventricular mass lesion and leptomeningeal and cerebral parenchymal infiltration by eosinophils, lymphocytes and macrophages. She had no history of either malignancy or allergic disorder. She complained of hearing disturbance caused by eosinophilic otitis media. Eosinophilia was detected in the peripheral blood. Hearing disturbance and eosinophilia improved with corticosteroid treatment. Six months later, she was admitted with disturbances of consciousness. Magnetic resonance imaging revealed a mass lesion in the right lateral ventricle and leptomeningeal involvement around the brain stem. Her symptoms deteriorated rapidly, and she died of brain stem malfunction. Autopsy demonstrated significant infiltration by eosinophils and lymphocytes into the mass lesion in the ventricle, subarachnoid space, perivascular space and parenchyma of the medulla oblongata. Histological examination of the bone marrow and other organs did not detect any evidence of parasites, malignancies, or systemic disorders in any organ. The final diagnosis was idiopathic HES. The present case shows that leptomeningeal dissemination and infiltration by eosinophils into the cerebral ventricles and brain stem should be considered in the course of idiopathic HES.
Recent studies have demonstrated essential functions for KIF3, a microtubule-directed protein motor, in subcellular transport of several cancer-related proteins, including the β-catenin–cadherin(s) complex. In this study, we report identification of the protein-phosphatase Dusp26 as a novel regulator of the KIF3 motor. Here we undertake yeast two-hybrid screening and identify Kif3a, a motor subunit of the KIF3 heterotrimeric complex, as a novel Dusp26-binding protein. Co-immunoprecipitation and colocalization experiments revealed that Dusp26 associates not only with Kif3a, but also with Kap3, another subunit of the KIF3 complex. Dephosphorylation experiments in vitro and analysis using mutant forms of Dusp26 in intact cells strongly suggested that Dusp26 is recruited to the KIF3 motor mainly by interaction with Kif3a, and thereby dephosphorylates Kap3. Forced expression of Dusp26, but not its catalytically inactive mutant, promoted distribution of β-catenin/N-cadherin, an established KIF3 cargo, to cell–cell junction sites, resulting in increased cell–cell adhesiveness. We also showed that Dusp26 mRNA expression was downregulated in human glioblastoma samples. These results suggest previously unidentified functions of Dusp26 in intracellular transport and cell–cell adhesion. Downregulation of Dusp26 may contribute to malignant phenotypes of glioma.
Object. To assess whether nimustine (ACNU), a drug that can cross the blood brain barrier, combined with radiotherapy, improved the survival of patients with primary central nervous system lymphoma (PCNSL).
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59-year-old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB-1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB-1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double-positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).
Adoptive immunotherapy using tumor-specific killer cells can be beneficial in inducing regression of advanced cancer. The roles of cytokines on effector cells in inducing maximal killing activity and the accompanying side-effects should be investigated in vitro and fully understood prior to their clinical use. The present study indicates that the gammadeltaT cells involved in autologous tumor-specific killing consist of several populations in terms of their T cell receptor (TCR) repertoire, but predominantly express the products of the Vgamma9/Vdelta2 gene locus of the TCR. We then examined the effect of TNF-alpha and IFN-gamma on these tumor-specific gammadeltaT cells for possible clinical use in cancer patients. TNF-alpha alone, at concentrations of 0.01-1.0 microg/ml, caused increased gammadeltaT cell cytotoxicity against autologous glioblastoma cells, whereas IFN-gamma alone had no effect. The combination of TNF-alpha (1 microg/ml) with IL-2 (50 units/ml) resulted in further enhancement of cytotoxicity. TNF-alpha, but not IFN-gamma, marginally inhibited the proliferative response of gammadeltaT cells; a similar result was seen when the cytokines were combined. TNF-alpha may, therefore, be one cytokine capable of inducing increased autologous tumor-specific activity in gammadeltaT cells, bearing mainly Vgamma9/Vdelta2 chains, which can be enhanced when combined with other cytokines.
Currently, some natural herbal extracts are believed to have a marked tumoricidal effect and low toxicity for normal tissues. We investigated the effect of relatively low molecular weight products extracted from the basidiomycete, Agaricus blazei Murill, on MethA tumor cell growth with the aim of producing synthetic derivatives based on these products. Inoculation of the low molecule fraction (LM) into the primary tumor of a two-tumor model resulted in the marked inhibition of the tumor, not only in the right flank, but also in the non-injected left flank. Chromatographic purification and physicochemical characterization showed the main tumoricidal activity to be located in a low molecule fraction-3 (LM-3), containing alpha-1,4-glucan-beta-1,6-glucan complex with an average molecular weight of 20 kDa. A11 LM fractions and crude ATF showed in vitro selective cytotoxicity for MethA tumor cells, having no effect on normal cells. Serum levels of immunosuppressive acidic protein (IAP) in mice receiving LM fractions, particularly LM-3, significantly increased, indicating the possible activation of granulocytes. We speculate that the inhibition of the distant tumor might be due to the increased migration of granulocytes, enhanced by the effect of extract injections at the primary tumor site.
Activation of peripheral blood mononuclear cells (PBMC) with IL-2 generates lymphokine-activated killer (LAK) cells that show a broad target cell range. In adoptive immunotherapy using in vitro-generated LAK cells, the intensity and specificity of their cytotoxic activity affect the prognosis of cancer patients. The present study was designed to examine the tumor-specific spectrum of T lymphocytes generated from the PBMC of patients with recurrent glioblastoma by in vitro propagation with IL-2 plus either soluble or solid-phase anti-CD3 monoclonal antibody (MAb) in short-term or long-term cultures. Both short-term and long-term culturing with solid-phase anti-CD3 MAb plus IL-2 yielded broad-reactivity CD8+ alphabetaT and gammadeltaT lymphocytes, both of which were non-MHC restricted, as shown by the fact that they were able to lyse autologous glioblastoma cells, MHC class I+II- allogeneic glioblastoma cells, and MHC class I-II-NK-sensitive K562 target cells. More importantly, these cells from patients failed to lyse fresh autologous PBMC. These results demonstrate that cells generated using this approach are non-MHC-restricted LAK cells and exhibit marked tumor specificity. In contrast, incubation with soluble anti-CD3 MAb generated T lymphocytes that after long-term culture, were either CD4+ or CD8+. These caused significant lysis of both allogeneic and autologous glioblastoma target cells, the extent of lysis being greater than that using cells produced by culturing with the solid-phase MAb. However, both the CD4+ and CD8+ cells also caused greater lysis of autologous normal PBMC, indicating that cells generated using this approach may cause significant adverse reactions in cancer patients if used for immunotherapy.
We have isolated a novel type of natural tumoricidal product from the basidiomycete strain, Agaricus blazei Murill. Using the double-grafted tumor system in Balb/c mice, treatment of the primary tumor with an acid-treated fraction (ATF) obtained from the fruit bodies resulted in infiltration of the distant tumor by natural killer (NK) cells with marked tumoricidal activity. As shown by electrophoresis and DNA fragmentation assay, the ATF also directly inhibited tumor cell growth in vitro by inducing apoptotic processing; this apoptotic effect was also demonstrated by increased expression of the Apo2.7 antigen on the mitochondrial membranes of tumor cells, as shown by flow-cytometric analysis. The ATF had no effect on normal mouse splenic or interleukin-2-treated splenic mononuclear cells, indicating that it is selectively cytotoxic for the tumor cells. Cell-cycle analysis demonstrated that ATF induced the loss of S phase in MethA tumor cells, but did not affect normal splenic mononuclear cells, which were mainly in the G0G1 phase. Various chromatofocussing purification steps and NMR analysis showed the tumoricidal activity to be chiefly present in fractions containing (1→4)-α-D-glucan and (1→6)-β-D-glucan, present in a ratio of approximately 1:2 in the ATF (molecular mass 170 kDa), while the final purified fraction, HM3-G (molecular mass 380 kDa), with the highest tumoricidal activity, consisted of more than 90% glucose, the main component being (1→4)-α-D-glucan with (1→6)-β branching, in the ratio of approximately 4:1.