Primary glial tumor patients treated by combining cis-platin and etoposide

Clinical Results of Unconventional Fractionation Radiotherapy in Central Nervous System Tumors

Malignant brain tumors (primary and metastatic) are apparently resistant to most therapeutic efforts. Several randomized trials have provided evidence supporting the efficacy of radiation therapy. Attempts at improving the results of external beam radiotherapy include altered fractionation, radiation sensitizers and concomitant chemotherapy. In low-grade gliomas, all clinical studies with radiotherapy have employed conventional dose fractionation regimens. In high-grade gliomas, hypofractionation schedules represent effective palliative regimens in poor prognosis subsets of patients; short-term survival in these patients has not allowed to evaluate late toxicity. In tumors arising within the central nervous system, hyperfractionated irradiation exploits the differences in repair capacity between tumour and late responding normal tissues. It may allow for higher total dose and may result in increased tumor cell kill. Accelerated radiotherapy may reduce the repopulation of tumor cells between fractions. It may potentially improve tumor control for a given dose level, provided that there is no increase in late normal tissue injury. In supratentorial malignant gliomas, superiority of accelerated hyperfractionated over conventionally fractionated schedules was observed in a randomized trial; however, the gain in survival was less than 6 months. At present no other randomized trial supports the preferential choice for altered fractionation irradiation. Also in pediatric brainstem tumors there are no data to confirm the routine use of hyperfractionated irradiation, and significant late sequelae have been reported in the few long-term survivors. Shorter treatment courses with accelerated hyperfractionated radiotherapy may represent a useful alternative to conventional irradiation for the palliation of brain metastases. Different considerations have been proposed to explain this gap between theory and clinical data. Patients included in dose/effect studies are not stratified by prognostic factors and other treatment-related parameters. This observation precludes any definite conclusion about the relative role of conventional and of altered fractionation. New approaches are currently in progress. More prolonged radiation treatments, up to higher total doses, could delay time to tumor progression and improve survival in good prognosis subsets of patients; altered fractionation may be an effective therapeutic tool to achieve this goal.

The Molecular Mechanisms of Plant-Derived Compounds Targeting Brain Cancer

Glioblastoma multiforme (GBM) is one of the most aggressive and malignant forms of brain tumors. Despite recent advances in operative and postoperative treatments, it is almost impossible to perform complete resection of these tumors owing to their invasive and diffuse nature. Several natural plant-derived products, however, have been demonstrated to have promising therapeutic effects, such that they may serve as resources for anticancer drug discovery. The therapeutic effects of one such plant product, n-butylidenephthalide (BP), are wide-ranging in nature, including impacts on cancer cell apoptosis, cell cycle arrest, and cancer cell senescence. The compound also exhibits a relatively high level of penetration through the blood-brain barrier (BBB). Taken together, its actions have been shown to have anti-proliferative, anti-chemoresistance, anti-invasion, anti-migration, and anti-dissemination effects against GBM. In addition, a local drug delivery system for the subcutaneous and intracranial implantation of BP wafers that significantly reduce tumor size in xenograft models, as well as orthotopic and spontaneous brain tumors in animal models, has been developed. Isochaihulactone (ICL), another kind of plant product, possesses a broad spectrum of pharmacological activities, including impacts on cancer cell apoptosis and cell cycle arrest, as well as anti-proliferative and anti-chemoresistance effects. Furthermore, these actions have been specifically shown to have cancer-fighting effects on GBM. In short, the results of various studies reviewed herein have provided substantial evidence indicating that BP and ICH are promising novel anticancer compounds with good potential for clinical applications.

Osthole suppresses the migratory ability of human glioblastoma multiforme cells via inhibition of focal adhesion kinase-mediated matrix metalloproteinase-13 expression

Glioblastoma multiforme (GBM) is the most common type of primary and malignant tumor occurring in the adult central nervous system. GBM often invades surrounding regions of the brain during its early stages, making successful treatment difficult. Osthole, an active constituent isolated from the dried C. monnieri fruit, has been shown to suppress tumor migration and invasion. However, the effects of osthole in human GBM are largely unknown. Focal adhesion kinase (FAK) is important for the metastasis of cancer cells. Results from this study show that osthole can not only induce cell death but also inhibit phosphorylation of FAK in human GBM cells. Results from this study show that incubating GBM cells with osthole reduces matrix metalloproteinase (MMP)-13 expression and cell motility, as assessed by cell transwell and wound healing assays. This study also provides evidence supporting the potential of osthole in reducing FAK activation, MMP-13 expression, and cell motility in human GBM cells.

Sepia ink oligopeptide induces apoptosis in prostate cancer cell lines via caspase-3 activation and elevation of Bax/Bcl-2 ratio

Sepia ink oligopeptide (SIO) is a tripeptide extracted from Sepia ink. To test the hypothesis that SIO inhibits prostate cancer by inducing apoptosis, the effects of SIO on the proliferation of three human prostate cancer cell lines were examined using a CCK-8 assay. SIO significantly inhibited the proliferation of DU-145, PC-3 and LNCaP cells in a time- and dose-dependent manner. Flow cytometry studies showed that exposing DU-145, PC-3 and LNCaP cells to 5, 10, or 15 mg/mL SIO for 24 h increased the percentage of the early-stage apoptotic cells from 11.84% to 38.26% (DU-145), 22.76% to 39.96% (PC-3) and 5.05% to 16.11% (LNCaP), respectively. In addition, typical morphologic changes were observed in the cells with acridine orange/ethidium bromide staining. SIO treatment induced strong S and G₂/M phase cell cycle arrest in a dose-dependent manner in DU-145 and LNCaP. In contrast, SIO treatment induced strong Sub G₁ and G₀/G₁ phase cell cycle arrest in a dose-dependent manner in PC-3. SIO exposure for 24 h decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the apoptogenic protein Bax. Moreover, the Bax/Bcl-2expression ratio was increased. Concurrently, the expression of caspase-3 was upregulated. These data support our hypothesis that SIO has anticarcinogenic properties.

Regulation of cellular growth, apoptosis, and Akt activity in human U251 glioma cells by a combination of cisplatin with CRM197

The aberrantly activated antiapoptotic phospatidyl-3-inositol-kinase (PI3K)/Akt signaling induced by cisplatin limits the effectiveness of chemotherapy; inhibition of this pathway may augment the sensitivity of tumor cells to cisplatin-induced toxicity and promote apoptosis. Cross-reacting material 197 (CRM197), the nontoxic mutant of diphtheria toxin, could act as an heparin-binding epidermal growth factor inhibitor and has been shown to have some anticancer effects, but the effect of CRM197 on glioma cells remains unclear. The aim of this study was to investigate the effects of a combination of cisplatin with CRM197 on the growth and apoptosis of human U251 glioma cells and the possible mechanism. In this study, we demonstrated that cisplatin or CRM197 induced a dose-dependent growth inhibition in U251 cells, but cisplatin at 5 µg/ml and CRM197 at 1 µg/ml did not affect the viability of human astrocytes. Cisplatin induced a time-dependent growth inhibition in U251 cells, whereas the growth-inhibitory effects induced by CRM197 alone or combined with cisplatin reached a peak at 24 h after treatment. Compared with the administration of cisplatin or CRM197 alone, CRM197 combined with cisplatin significantly enhanced U251 cell growth inhibition and apoptosis. Cisplatin induced sustained activation of Akt, whereas CRM197 markedly suppressed the Akt phosphorylation induced by cisplatin. The effects of growth inhibition and apoptosis were markedly enhanced after a combination of cisplatin with CRM197 plus the PI3K inhibitor LY294002 or wortmannin. Therefore, CRM197 combined with cisplatin could enhance growth inhibition and apoptosis of glioma cells by inhibiting the cisplatin-induced PI3K/Akt pathway.

Drug-resistance gene expression and progression of astrocytic tumors

To clarify the influence of biochemotherapy on the progression of astrocytic tumors, the expression of O6-methylguanine DNA-methyltransferase (MGMT) mRNA, as well as of other drug-resistance- and drug-sensitivity-related genes such as multidrug resistance gene 1, multidrug resistance-associated protein, glutathione S-transferase-pi, DNA topoisomerase II, and interferon receptor mRNA, and the interferon regulatory factor (IRF)-1 and -2 ratios in gliomas were investigated by quantitative reverse transcription-polymerase chain reaction (RT-PCR). The mean MGMT/beta2-microglobulin (beta2-MG) ratio for 130 neuroepithelial tumors was 8.2 +/- 17.8. The mean ratio of 45 glioblastomas was significantly higher than that for the other 85 tumors. In contrast, the mean of 26 low-grade gliomas was significantly lower than that of other tumors. The mean IRF-1/IRF-2 ratio of 16 other brain tumors that mainly consisted of medulloblastomas was significantly greater than that of the other 114 tumors. Almost no significant differences were observed between primary and recurrent tumors in the expression of any gene, and before and after therapy with corresponding drugs. The mean MGMT/beta2-MG ratio in primary glioblastomas was significantly higher than that in secondary tumors. These findings suggest that native drug resistance is more important than acquired resistance when glioma therapy is considered.

Local interstitial delivery of z-butylidenephthalide by polymer wafers against malignant human gliomas

We have shown that the natural compound z-butylidenephthalide (Bdph), isolated from the chloroform extract of Angelica sinensis, has antitumor effects. Because of the limitation of the blood-brain barrier, the Bdph dosage required for treatment of glioma is relatively high. To solve this problem, we developed a local-release system with Bdph incorporated into a biodegradable polyanhydride material, p(CPP-SA; Bdph-Wafer), and investigated its antitumor effects. On the basis of in vitro release kinetics, we demonstrated that the Bdph-Wafer released 50% of the available Bdph by the sixth day, and the release reached a plateau phase (90% of Bdph) by the 30th day. To investigate the in situ antitumor effects of the Bdph-Wafer on glioblastoma multiforme (GBM), we used 2 xenograft animal models-F344 rats (for rat GBM) and nude mice (for human GBM)-which were injected with RG2 and DBTRG-05MG cells, respectively, for tumor formation and subsequently treated subcutaneously with Bdph-Wafers. We observed a significant inhibitory effect on tumor growth, with no significant adverse effects on the rodents. Moreover, we demonstrated that the antitumor effect of Bdph on RG2 cells was via the PKC pathway, which upregulated Nurr77 and promoted its translocation from the nucleus to the cytoplasm. Finally, to study the effect of the interstitial administration of Bdph in cranial brain tumor, Bdph-Wafers were surgically placed in FGF-SV40 transgenic mice. Our Bdph-Wafer significantly reduced tumor size in a dose-dependent manner. In summary, our study showed that p(CPP-SA) containing Bdph delivered a sufficient concentration of Bdph to the tumor site and effectively inhibited the tumor growth in the glioma.

Which therapy works better in choroid plexus carcinomas?

Choroid plexus carcinomas (CPCs) are rare tumors with dismal outcome. While it has been established that surgery, radiotherapy, and chemotherapy improve survival, the best chemotherapy drugs for treating this disease still need to be identified. Since CPC is too rare to permit a prospective clinical trial, we performed a meta-analysis to evaluate the effects of individual drugs in patients with CPCs. We expanded a pre-existing database and included all cases of choroid plexus tumors, identified in PubMed through the end of 2007, for a total of 906 patients. At first, we restricted the analysis to patients with histologically confirmed CPC (n = 361) and with residual tumor after surgery (n = 130/361 patients), and we compared response and survival between patients who received a particular drug and those who did not. Response to chemotherapy was documented in 43 patients. Of the drugs used in these patients, etoposide was associated with the highest response rate (17/36). Next survival was compared among all CPC. Kaplan-Meier curves and log-rank tests suggested a statistically significant treatment benefit for cyclophosphamide, etoposide, and carboplatin, while the effect of vincristine was found to be marginally significant (P = 0.07, log rank). Of these, only etoposide's effect could be confirmed in a limited Cox multiple regression analysis. In conclusion, etoposide should be included in future standard treatment protocols. However the survival rates are still unsatisfactory, and additional novel drugs should be studied in prospective multicenter studies.

Bradykinin-induced cell migration and COX-2 production mediated by the bradykinin B1 receptor in glioma cells

Bradykinin is produced and acts at the site of injury and inflammation. Recent reports have also shown that bradykinin selectively modulates blood-tumor barrier permeability. However, the molecular mechanisms and pathologic roles underlying bradykinin-induced glioma migration remain unclear. Glioma is the most common primary adult brain tumor, with a poor prognosis because of the ease with which tumor cells spread to other regions of the brain. In this study, we found that bradykinin increases the cell migration and expression of cyclo-oxygenase-2 (COX-2) in glioma cells. Bradykinin-mediated migration was attenuated by the selective COX-2 inhibitor NS-398. Moreover, increased motility of glioma cells and expression of COX-2 were mimicked by a bradykinin B1 receptor (B1R) agonist and markedly inhibited by a B1R antagonist. Bradykinin-mediated migration was attenuated by phosphoinositide 3-kinase (PI-3 kinase)/AKT inhibitors LY 294002 and wortmannin. Bradykinin stimulation also increased the phosphorylation of the p85 subunit of PI-3 kinase and serine 473 of AKT. Treatment of bradykinin with AP-1 inhibitors Tanshinone IIA and curcumin also reduced COX-2 expression and glioma cell migration. Moreover, treatment of bradykinin also induced phosphorylation of c-Jun in glioma cells. AP-1 promoter analysis in the luciferase reporter construct showed that bradykinin increased AP-1 transcription activity and was inhibited by LY 294002 and wortmannin. One mechanism underlying bradykinin-directed migration is transcriptional up-regulation of COX-2 and activation of the B1R receptor, PI-3 kinase, AKT, c-Jun, and AP-1 pathways.

Combination treatment with resveratrol and sulforaphane induces apoptosis in human U251 glioma cells

Resveratrol is a naturally occurring polyphenolic compound highly enriched in grapes, peanuts, red wine, and a variety of food sources. Sulforaphane belongs to the family of isothiocyanates and is highly enriched in cruciferous vegetables. Our previous study showed that resveratrol, when used at high concentrations, inhibited cell proliferation, caused the cell cycle arrest and induced apoptotic cell death in glioma cells. In the current study, we tested the effect of combination treatment with resveratrol and sulforaphane, when both were used at low concentrations, on cell proliferation, migration and death in human U251 glioma cells. Our study shows that combination treatment with resveratrol and sulforaphane inhibits cell proliferation and migration, reduces cell viability, induces lactate dehydrogenase release, decreases pro-survival Akt phosphorylation and increases caspase-3 activation. The use of combination of bioactive food components, such as resveratrol and sulforaphane, may be a viable approach for the treatment of glioma.

Carboplatin and etoposide (CE) chemotherapy in patients with recurrent or progressive oligodendroglial tumors

BACKGROUND

Oligodendroglial tumors are rare and chemosensitive diseases; but the overall results with current chemotherapy regimens cannot be considered satisfactory and other active treatments are necessary. We decided to determine the efficacy and toxicity profile of the carboplatin and etoposide (CE) regimen in this setting.

METHODS

In this phase II trial we evaluated the response rate of first or second line CE regimen (Carboplatin AUC 5 on day 1 and Etoposide 120 mg/m2 on days 1-3 every 28 days) in patients with recurrent/progressive oligodendroglial tumors.

RESULTS

Thirty-two patients were enrolled. Median age was 42 years (range 22-66); median ECOG PS was 0 (range 0-2); 9 patients had oligodendroglioma, 3 patients had oligoastrocytoma, 11 patients had anaplastic oligodendroglioma, 9 patients had anaplastic oligoastrocytoma. CE regimen showed a response rate of 46.9% with 5 complete responses (15.6%) and 10 partial responses (31.3%). Eleven patients (34.4%) had stable disease. Median time to progression was 8 months, progression-free survivals at 6 and 12 months were 80% and 46.9%, respectively. Toxicity was mainly hematological, with grade 3-4 neutropenia in 5 (15.6%) patients.

CONCLUSIONS

In this trial CE regimen has shown relevant activity with a favourable safety profile.

Antisense oligonucleodes targeting the focal adhesion kinase inhibit proliferation, induce apoptosis and cooperate with cytotoxic drugs in human glioma cells

To examine the role of focal adhesion kinase in human glioma cells, we studied its effects on proliferation and apoptosis using FAK antisense oligonucleotide. U251 MG cells were transfected with ODNs, sense FAK, mismatch FAK and antisense-FAK, respectively. Expression of FAK proteins were detected by Western blots and Immnofluoressence. Cell apoptosis and mitochondrial membrane potential were analyzed by flow cytometry. Caspase-3 activity was measured by spectrofluorometer. MTT assay was used to examine changes in cell proliferation. The protein expression of FAK in U251 MG cells decreased in antisense-FAK ODNs group significantly. Caspase-3 activity increased in cells treated with antisense-FAK and down-regulated when treated with caspase-3 inhibitor. The level of cell apoptosis and loss of mitochondrial membrane potential in antisense-FAK group was higher than in the mismatch sense group. Cells proliferation was inhibited by antisense-FAK, and the effects were clearly additive when antisense oligonuceotides were added to cells treated with the anticancer agents. The results suggest that antisense-FAK ODNs inhibit U251 MG cells proliferation and induce their apoptosis. It is possible that FAK via mitochondrial and caspase-3 inhibits U251 MG cells apoptosis. And antisense oligonucleotide treatment enhances U251 MG cells sensitivity to chemotherapy.

The Antitumor Effects of Angelica sinensis on Malignant Brain Tumors In vitro and In vivo

PURPOSE

In this study, we have examined the antitumor effects of chloroform extract of Angelica sinensis (AS-C), a traditional Chinese medicine, on glioblastoma multiforme (GBM) brain tumors in vitro and in vivo.

EXPERIMENTAL DESIGN

In vitro, GBM cells were treated with AS-C, and the cell proliferation, changes in distributions of cell cycle, and apoptosis were determined. In vivo, human DBTRG-05MG and rat RG2 GBM tumor cells were injected s.c. or i.c. and were treated with AS-C. Effects on tumor growth were determined by tumor volume, magnetic resonance imaging, survival, and histology analysis.

RESULTS

The AS-C displays potency in suppressing growth of malignant brain tumor cells without cytotoxicity to fibroblasts. Growth suppression of malignant brain tumor cells by AS-C results from cell cycle arrest and apoptosis. AS-C can up-regulate expression of cdk inhibitors, including p21, to decrease phosphorylation of Rb proteins resulting in cell arrest at the G0-G1 phase for DBTRG-05MG and RG2 cells. The apoptosis-associated proteins are dramatically increased and activated in DBTRG-05MG cells and RG2 cells by AS-C but RG2 cells without p53 protein expression. In vitro results showed AS-C triggered both p53-dependent and p53-independent pathways for apoptosis. In in vivo studies, AS-C not only can suppress growths of malignant brain tumors of rat and human origin but also shrink the volumes of in situ GBM, significantly prolonging survivals.

CONCLUSIONS

The in vitro and in vivo anticancer effects of AS-C indicate that it has sufficient potential to warrant further investigation and development as a new anti-brain tumor agent.

Phase II trial of carboplatin and etoposide for patients with recurrent high-grade glioma

We present the results of a phase II trial of carboplatin and etoposide (CE) combination as first-line chemotherapy in patients with recurrent glioblastoma multiforme (GBM) and anaplastic astrocytoma (AA) after surgery and radiotherapy. We assess the activity and the tolerability of this combination. 30 patients with GBM (25) and AA (5) were treated with VP-16 (etoposide) 120 mg m⁻² and CBCDA (carboplatin) 100 mg m⁻² for 3 days every 4 weeks. Moreover, we performed a retrospective analysis of topoisomerase IIα gene status using chromogenic in situ hybridisation. The median age was 54 years (21–73 years); Eastern Cooperative Oncology Group performance score was 0-1 in 25 patients and 2 in five patients. All patients had been previously treated with surgical resection (21 radical resections) followed by radiation therapy (40–60 Gy). We observed six (20%) complete responses, three (10%) partial responses and 12 (40%) stable diseases, with a response rate of 30%. The median time to progression was 4 months, while progression-free survival at 6 months was 33.3%. The median survival time was 10 months. Neutropenia occurred in 9 patients: four patients had grade 4, two patients grade 3 and three patients grade 2. In the conclusion of this clinical trial, the CE combination has shown activity in recurrent GBM and AA, with a good toxicity profile. Alterations in the copy number of topoisomerase IIα gene seem to be a rare event and in our series do not influence response to the CE combination.

Differential responsiveness among "high risk" pediatric brain tumors in a pilot study of dose-intensive induction chemotherapy

BACKGROUND

These factors have been predictive for progressive disease on therapy (PDOT) among pediatric brain tumors: >1.5 cm(2) unresectable tumor, glioblastoma, supratentorial primitive neuroectodermal tumor, and metastatic medulloblastoma (MBL). This pilot study sought to correlate cytoreductive response with progression free survival.

PROCEDURES

Four courses of cisplatinum, cyclophosphamide, etoposide, and vincristine preceded hyperfractionated radiotherapy (RT). Maintenance chemotherapy consisted of eight cycles of carboplatin, etoposide, and vincristine. Biopsy specimens were immunohistochemically studied for labeling index, hypoxia, and multidrug resistance proteins.

RESULTS

Twenty newly diagnosed patients [nine primitive neuroectodermal tumors/MBL, one choroid plexus carcinoma, eight malignant gliomas, and two anaplastic ependymomas] were treated. Ten patients, who required neuraxis irradiation, constituted the "PNET" group. These demonstrated five complete and one partial response (PR), with an estimated median progression free survival of 44 months and median survival in excess of 53 months. Patients treated with involved field irradiation were designated the "Glioma" group. Induction chemotherapy produced partial and minor responses (MRs) among 5/10. Their estimated median progression free survival was 6.9 months (P = 0.035 relative to the PNET) with a median survival of 10.7 months (P = 0.04). Age, labeling index, the presence of hypoxia, and Pgp/MDR1 expression failed to discriminate between the two groups.

CONCLUSIONS

This induction regimen produced a cytoreductive response in 6/10 and achieved a significant improvement in progression free survival among 7/10 in the PNET group. Unfortunately, responses among Glioma patients did not translate into durable control. Expression of the biologic factors was similar between both groups and did not correlate with diagnosis or response.

Response to a phase II study of concomitant-to-sequential use of etoposide and radiation therapy in newly diagnosed malignant gliomas

We evaluated the antitumor efficacy of and patient tolerance to a phase II study of concomitant-to-sequential use of etoposide and radiotherapy for newly diagnosed malignant gliomas. Fifty-two supratentorial malignant glioma patients were enrolled in this phase II study between May 1995 and May 1998. Standard cranial irradiation and six courses of etoposide (100 mg/m2 - xdays 1-3) were administered. The first course of etoposide was given on days 1 to 3 of radiotherapy and was resumed in the week following the end of radiotherapy. Treatment was consolidated by further courses of etoposide every 4 weeks. Fifty-one patients were assessable for toxicity, response, and survival. A complete surgical resection was only noted for 17 patients. Six patients had a confirmed complete response, and eight patients displayed a partial response. Six patients progressed within the first 3 months of starting treatment. The rate of objective response for assessable patients with residual tumor was 41.1%. Hematologic toxicity was mild; grade 3 or 4 neutropenia was noted in five patients, without sepsis. The overall median survival time (MST) was 12.5 months, and the mean survival of this population was 14.9 months. These results suggest a certain efficacy of this regimen testing a concomitant-to-sequential use of etoposide and radiotherapy for newly diagnosed malignant gliomas, and that continued evaluation of this combination is warranted, especially because this treatment is also well tolerated.

In vitro growth suppression of human glioma cells by a 16-mer oligopeptide: a potential new treatment modality for malignant glioma

Fibroblast growth factor-2 (FGF-2) is involved as an autocrine growth factor in the autonomous proliferation of glioma cells. To develop a new strategy for treating patients with glioma, we studied the effect on human glioma cells of a 16-mer oligopeptide with conformational similarity to the putative receptor-binding domain of FGF-2. A synthesized oligonucleotide was assessed its receptor-binding activity by BIAcore instrument. Its biological effect on glioma cell lines was examined in vitro by MTT assay. The peptide suppressed the in vitro growth of human glioma cells U87MG, T98G and U251MG cells, but not of A431 cells whose growth is not dependent on FGF-2. Apoptotic bodies were noted after 24-h incubation in the presence of the peptide; Ac-YVAD-CHO, a caspase-3 inhibitor, suppressed apoptosis. Furthermore, we examined the modulation of the cytotoxic effect of anticancer drugs by the oligopeptide. The addition of this oligopeptide to the chemotherapeutic agents CDDP, ACNU and VP16 had additive effects in vitro. These results suggest that the pathway of the FGF-2 autocrine loop through the FGF receptor plays an important role in the proliferation of glioma cells. New drugs targeting this loop may be highly effective in treating FGF-2-dependent tumors. Our results suggest that its addition to the therapeutic arsenal may lead to improved treatment regimens for patients with FGF-2-dependent tumors.

A phase II study of radiotherapy after hyperbaric oxygenation combined with interferon-beta and nimustine hydrochloride to treat supratentorial malignant gliomas

Hypoxic cells play a key role in the radioresistance of malignant glioma. Interferon-beta, ACNU as nimustine hydrochloride and radiotherapy (IAR) is a common therapy for malignant glioma in Japan. Since hyperbaric oxygenation (HBO) increases oxygen pressure in glioma tissue, we applied a modified IAR therapy, radiotherapy after HBO combined with interferon-beta and ACNU (HBO/IAR therapy), for supratentorial malignant gliomas. Daily radiation therapy was completed within 15 min after HBO. We assessed HBO/IAR with respect to toxicity, response rates and the time of tumor progression (TTP). We also examined the incidence of responses by some prognostic factors before HBO/IAR, namely, age, Karnofsky performance scale (KPS), histological type, tumor size, tumor site and operation type. Of 39 patients who participated in this study, 35 underwent a complete schedule of HBO/IAR therapy in which toxicity was permissible. Thirty patients (76.9%) either maintained or increased KPS during HBO/IAR with a mean duration of 68 +/- 14 days. The response rates (CR + PR%) for glioblastoma, anaplastic astrocytoma and overall were 50%, 30% and 43%, respectively. The incidence of therapeutic responses among all prognostic factors before HBO/IAR did not significantly differ. Median TTP for patients with glioblastoma, patients with anaplastic astrocytoma, and overall were 38, 56 and 43 weeks, respectively. The present study suggested that HBO/IAR therapy could be applied to especially patients with poor prognostic factors, because of its short treatment period, its permissible toxicity and identical response to patients with good prognostic factors.

O6-methylguanine-DNA methyltranspherase gene expression in gliomas by means of real-time quantitative RT-PCR and clinical response to nitrosoureas

O(6)-methylguanine-DNA methyltransferase (MGMT) mRNA expressions were examined in 100 neuroepithelial tumors by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) using SYBR Green I. The mean relative quantitation value of MGMTmRNA normalized to the level of beta2-microglobulin for 100 tumors was 5.3 +/- 11.2. The mean value of 41 glioblastomas was significantly higher than that for the other 59 tumors (p = 0.0008 by Student's t-test). In contrast, the means of 19 low-grade gliomas and 12 medulloblastomas were significantly lower than that of other tumors (p = 0.0282 and p = 0.0456 by Student's t-test). Among the 55 retrospective patients who had been treated with 1-(4-amino-2-methyl-5-pyrimidynyl)methyl-3-(2-chloroethyl)- 3-nitrosourea hydrochloride (ACNU), the value was a significant independent predictor of the effect of initial therapy with ACNU (p = 0.0007 by Mann-Whitney U-test) and the survival period (p = 0.0175 by Wald test). The value >or=1 was the most significant factor in predicting the initial effect of treatment by multi-variant regression analysis (p < 0.0001). These results suggest that our individual adjuvant therapy based on MGMTmRNA expression may be improved by the application of real-time quantitative RT-PCR.

Preradiation chemotherapy in primary high-risk brainstem tumors: phase II study CCG-9941 of the Children's Cancer Group

PURPOSE

This Children's Cancer Group group-wide phase II trial evaluated the efficacy and toxicity of two chemotherapy arms administered before hyperfractionated external-beam radiotherapy (HFEBRT).

PATIENTS AND METHODS

Thirty-two patients with newly diagnosed brainstem gliomas were randomly assigned to regimen A and 31 to regimen B. Regimen A comprised three courses of carboplatin, etoposide, and vincristine; regimen B comprised cisplatin, etoposide, cyclophosphamide, and vincristine. Both arms included granulocyte colony-stimulating factor. Patients were evaluated by magnetic resonance imaging after induction chemotherapy and HFEBRT at a dose of 72 Gy.

RESULTS

Ten percent +/- 5% of regimen A patients objectively responded to chemotherapy. For combined induction and radiotherapy, 27% +/- 9% of patients improved. The neuroradiographic response rate for regimen B was 19% +/- 8% for chemotherapy and 23% +/- 9% after HFEBRT. Response rates were not statistically significant between regimens after induction or chemotherapy/HFEBRT. Event-free survival was 17% +/- 5% (estimate +/- SE) at 1 year and 6% +/- 3% at 2 years. Survival was significantly longer among patients who responded to chemotherapy (P <.05). Among patients who received regimen A induction, grades 3 and 4 leukopenia were observed in 50% to 65%, with one toxicity-related death. For regimen B, severe leukopenia occurred in 86% to 100%, with febrile neutropenia in 48% to 60% per course.

CONCLUSION

Neither chemotherapy regimen meaningfully improved response rate, event-free survival, or overall survival relative to previous series of patients with brainstem gliomas who received radiotherapy with or without chemotherapy.

Effect of expression of P-glycoprotein on technetium-99m methoxyisobutylisonitrile single photon emission computed tomography of brain tumors

The expression of P-glycoprotein was investigated immunohistochemically in 26 brain tumor tissues and compared with the findings of technetium-99m methoxyisobutylisonitrile single photon emission computed tomography (99mTc-MIBI SPECT) to clarify the effect of P-glycoprotein on the diagnostic accuracy. P-glycoprotein labeling index of both tumor cells and vascular endothelial cells showed no clear relationship with the findings of 99mTc-MIBI SPECT imaging. Expression of P-glycoprotein has no effect on the diagnostic accuracy of 99mTc-MIBI SPECT.

Pharmacotherapy of malignant astrocytomas of children and adults: current strategies and future trends

This article reviews the conceptual progression in the pharmacological therapy of malignant astrocytoma (MA) over the past decade, and its future trends. It is a selective rather than an exhaustive inventory of literature citations. The experience of the Brain Tumour Cooperative Group (BTCG) and earlier phase III trials are summarised to place subsequent phase II and I studies of single and combination agent chemotherapy in perspective. The BTCG experience of the 1970s to 1980s may be summarised to indicate that external beam radiotherapy (EBRT) is therapeutic, although not curative, and not further improved upon by altering fractionation schedules, or the addition of radioenhancers. Whole brain and reduced whole brain EBRT with focal boost were comparable regimens. Nitrosourea-based, adjuvant chemotherapy provided a modest improvement in survival among adult patients, which was comparable with that of other single drugs or multidrug regimes. The multiagent schedules, however, had a correspondingly higher toxicity rate. Intra-arterial administration was associated with significant risk, which conferred no therapeutic advantage. The trend of the past decade has been towards multiagent chemotherapy although its benefit cannot be predicted from the classic prognostic factors. Published experience with investigational trials utilising myeloablative chemotherapy with autologous bone marrow or peripheral blood stem cell haemopoietic support, drug delivery enhancement methods and radiosensitisers is critically reviewed. None of these approaches have achieved wide-spread acceptance in the treatment of adult patients with MA. Greater attention is placed on recent 'chemoradiotherapy' trials, which attempt to integrate and maximise the cytoreductive potential of both modalities. This approach holds promise as an effective means to delay or overcome the evolution of tumour resistance, which is probably one of the dominant determinants of prognosis. However, the efficacy of this approach remains unproven. New chemotherapeutic agents as well as biological response modifiers, protein kinase inhibitors, angiogenesis inhibitors and gene therapy are also discussed; their role in the therapeutic armamentarium has not been defined.

Intra-arterial cisplatin plus oral etoposide for the treatment of recurrent malignant glioma: a phase II study

Twenty-five adults with recurrent malignant glioma were enrolled into a phase II clinical study. All patients had undergone surgical resection and had failed radiotherapy and first-line treatment with nitrosourea-based chemotherapy; five had failed second-line chemotherapy. Our objective was to test the efficacy of combining intra-arterially (i.a.) infused cisplatin and oral etoposide. Using conventional angiographic technique to access anterior/posterior cerebral circulation, cisplatin 60 mg/m2 was administered by i.a. infusion on day 1 of treatment. Oral etoposide 50 mg/m2/day was given days 1-21, with a 7 day rest interval between courses. Response to treatment was evaluated in 20 patients. Two patients with anaplastic astrocytoma had partial responses (PR) and six patients experienced stable disease (SD) for an overall response rate (PR +/- SD) of 40%. The median time to disease progression (MTP) following treatment for the responder subgroup was 18 weeks. The median survival time from treatment (MST) for the responders (n = 8) and non-responders (n = 12) was 56.5 weeks and 11 weeks, respectively. Combined i.a. cisplatin and oral etoposide was well-tolerated, but produced an objective response in only a minority of patients. Those considered responders (PR + SD) experienced significant survival advantage when compared to the non-responders. Nonetheless, i.a. delivery of chemotherapy is an expensive and technologically burdensome treatment for most patients to access, requiring proximity to a major center with neuro-oncological and neuroradiological clinical services. This is of special concern for patients suffering recurrent disease with progressive neurological symptoms at a time in their course when quality of life must be safeguarded and palliation of symptoms should be the therapeutic goal. Despite the efforts of previous investigators to use this combination of agents to treat recurrent malignant glioma, we cannot recommend the use of i.a. chemotherapy for salvage treatment of this disease.

Preliminary individual adjuvant therapy for gliomas based on the results of molecular biological analyses for drug-resistance genes

New adjuvant therapy individualized by the results of reverse transcription-polymerase chain reaction (RT-PCR) for drug-resistance genes has been used to treat malignant gliomas. Protocol studies for malignant gliomas were not so encouraging in their therapeutic results because of heterogeneity and the various drug-sensitivities of the tumors. Individualization of glioma therapy is recommended. Drug-resistance genes messenger ribonucleic acid (mRNA) expressions were investigated in drug-resistant human glioma cell lines derived from U87MG and 46 frozen samples of retrospectively examined neuroepithelial tumors (12 low grade neuroepithelial tumors, 16 Grade III gliomas, 11 glioblastomas, and 7 other malignant neuroepithelial tumors such as medulloblastomas and primitive neuroectodermal tumors) by RT-PCR with the specific primers for O6-methylguanine DNA methyltransferase (MGMT), multidrug-resistance gene 1 (MDR1), multidrug-resistance-associated protein (MRP), and glutathione-S-transferase-pi (GST-pi). Thirty-seven preliminary individual adjuvant therapies (IAT) based on RT-PCR results, mainly in MGMT expression, were performed on 30 consecutive patients with neuroepithelial tumors. In the retrospectively examined series, the initial response to 1-(4-amino-2-methyl-5-pyrimidynyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) was correlated most significantly to the MGMT mRNA expression among 11 independent prognostic factors (p = 0.0037) in multivariate logistic regression analysis. In the preliminary IAT, 17 of 32 evaluable therapies had a partial or complete response (53.1% response rate). Our IAT based on RT-PCR seemed to be more effective than conventional therapies for malignant gliomas.

A phase II study of nimustine hydrochloride, cisplatin, and etoposide combination chemotherapy for supratentorial malignant gliomas

Twenty-eight patients who were previously treated by aggressive surgery and radiation and were diagnosed with supratentorial malignant gliomas received a combination of nimustine hydrochloride; 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), cisplatin and etoposide (ACE therapy) as primary treatment. Cisplatin and etoposide were given at doses of 20 and 60 mg/m2/day for 5 days, respectively, ACNU doses 80 mg/m2/day on the first day. Treatment was repeated at 4-week intervals for up to 3 cycles. Seventeen patients (60.7%) complained of nausea. Grade 3 or 4 hematological toxicity occurred in 11 patients (39.3%), and grade 3 or 4 renal toxicity occurred in 2 patients. The percentage of patients who showed complete or partial response was 28.6% (8/28). The median time of tumor progression was 40 weeks, and the median survival time was 146 weeks. There were some long-surviving patients who may have benefited from ACE combination. This study demonstrated the effects of ACE combination in patients with supratentorial malignant gliomas.

Initial and maintenance combination treatment with interferon-beta, MCNU (Ranimustine), and radiotherapy for patients with previously untreated malignant glioma

Combined treatment with interferon-beta, MCNU (Ranimustine), and radiotherapy was assessed in patients with malignant glioma who had not received previous cytotoxic drug therapy. Forty-three patients up to 75 years old with histopathologically confirmed malignant glioma were studied. All patients had tumors measurable by neuroimaging, a Karnofsky performance score exceeding 40, and an expected survival exceeding 2 months. A response rate of 49% (21/45) was observed, including 6 complete remissions (14%) and 15 partial remissions (35%). Of the 43 patients who completed initial therapy, 19 were given sequential maintenance therapy. Survival time was much longer with than without maintenance therapy. Toxic side effects were moderate and did not substantially affect patients' general condition. We concluded that this combination therapy had a pronounced effect on untreated malignant glioma, particularly in patients whose initial therapy was followed up with maintenance therapy.

A peptide derived from the non-receptor-binding region of urokinase plasminogen activator inhibits glioblastoma growth and angiogenesis in vivo in combination with cisplatin

The urokinase plasminogen activator system is involved in angiogenesis and tumor growth of malignant gliomas, which are highly neovascularized and so may be amenable to antiangiogenic therapy. In this paper, we describe the activity of A6, an octamer capped peptide derived from the non-receptor-binding region of urokinase plasminogen activator. A6 inhibited human microvascular endothelial cell migration but had no effect on the proliferation of human microvascular endothelial cells or U87MG glioma cells in vitro. In contrast, A6 or cisplatin (CDDP) alone suppressed subcutaneous tumor growth in vivo by 48% and 53%, respectively, and, more strikingly, the combination of A6 plus CDDP inhibited tumor growth by 92%. Such combination treatment also greatly reduced the volume of intracranial tumor xenografts and increased survival of tumor-bearing animals when compared with CDDP or A6 alone. Tumors from the combination treatment group had significantly reduced neovascularization, suggesting a mechanism involving A6-mediated inhibition of endothelial cell motility, thereby eliciting vascular sensitivity to CDDP-mediated toxicity. These data suggest that the combination of an angiogenesis inhibitor that targets endothelial cells with a cytotoxic agent may be a useful therapeutic approach.

Radiation therapy of the older patient

Radiotherapy has a major role in the multidisciplinary approach to cancer therapy. It is widely used for curative and palliative treatment of cancer involving various sites. Radiotherapy is of particular benefit to older and frail cancer patients as an alternative to surgery and to systemic therapy. The available data on the sensitivity of normal tissues to radiotherapy in elderly patients strongly suggest that older patients with good functional status tolerate radiotherapy as well as younger patients and have comparable tumor response and survival rates. Aggressive radiotherapy should not be withheld from older patients because of chronological age alone.

[Sensitivity to etoposide of human malignant glioma cell lines. Mechanisms of action]

AIM OF THE STUDY

Etoposide, a Topoisomerase II inhibitor agent, is currently being explored as a therapeutic agent for brain tumors. The aim of this experimental study was to compare the in vitro etoposide sensitivity of human glioma cells vs human squamous cell carcinoma (SCC) cells.

MATERIAL AND METHODS

Twelve human cell lines (six malignant glioma cell lines and six head and neck SCC cell lines) were used for this comparative study. A standard colony formation assay was used to assess cell survival. Since Topoisomerase II is the critical target for etoposide, it was of interest to determine Topoisomerase II activity and etoposide induced inhibition of Topoisomerase II activity for the glioma cells vs the SCC cells.

RESULTS

Except for etoposide-induced inhibition of Topoisomerase II activity, no difference was found for etoposide sensitivity and Topoisomerase II activity between the both type of cells.

CONCLUSION

These results suggested that the Topoisomerase II reactive agents may prove to be clinically a useful drug for patients presenting with malignant gliomas.

Drug resistance of human glioblastoma cells conferred by a tumor-specific mutant epidermal growth factor receptor through modulation of Bcl-XL and caspase-3-like proteases

Alterations of the epidermal growth factor receptor (EGFR) gene occur frequently in human malignant gliomas. The most common of these is deletion of exons 2-7, resulting in truncation of the extracellular domain (DeltaEGFR or EGFRvIII), which occurs in a large fraction of de novo malignant gliomas (but not in progressive tumors or those lacking p53 function) and enhances tumorigenicity, in part by decreasing apoptosis through up-regulation of Bcl-XL. Here, we demonstrate that the DeltaEGFR concomitantly confers resistance to the chemotherapeutic drug cisplatin (CDDP) by suppression of CDDP-induced apoptosis. Expression of Bcl-XL was elevated in U87MG.DeltaEGFR cells prior to and during CDDP treatment, whereas it decreased considerably in CDDP-treated parental cells. CDDP-induced activation of caspase-3-like proteases was suppressed significantly in U87MG.DeltaEGFR cells. These responses were highly specific to constitutively kinase-active DeltaEGFR, because overexpression of kinase-deficient DeltaEGFR (DK) or wild-type EGFR had no such effects. Correspondingly, DeltaEGFR specific tyrosine kinase inhibitors reduced Bcl-XL expression and potentiated CDDP-induced apoptosis in U87MG.DeltaEGFR cells. Ectopic overexpression of Bcl-XL in parental U87MG cells also resulted in suppression of both caspase activation and apoptosis induced by CDDP. These results may have important clinical implications for the use of CDDP in the treatment of those malignant gliomas expressing DeltaEGFR.

Treatment of recurrent malignant supratentorial gliomas with the association of carboplatin and etoposide: a phase II study

Thirty one patients previously treated with surgery, radiation therapy and chemotherapy with a nitrosourea for malignant supratentorial gliomas received a combination of carboplatin (CBDCA) and etoposide (VP16) at tumor progression. Carboplatin and etoposide (CE) were given, each at a dose of 100 mg/m2/day from day 1 to 3. The response was evaluated at each course and a minimum of three course was required to definite stable patient. Tolerance was evaluated in 31 patients. None had renal or auditory toxicity. Side effects consisted of grade III hematologic toxicity in 6 patients (19%), and grade III hepatic toxicity in one patient. No grade IV WHO toxicity was observed. All 31 patients could be evaluated for therapeutic response. A partial response was noted in 4 patients during 13, 34 +, 35 + and 51 + weeks. Ten patients had stable disease after a minimum of 3 courses (19 to 37 weeks). The rate of partial response (PR) and stabilisation (S) was 45% (14/31). The median time to tumor progression (MTTP) for responding and stable patients was 28 weeks. The median survival time (ST) for the entire group was 45 weeks and over 51 weeks for PR and S patients.

Recognition and management of gliomas

Gliomas are the most frequent primary brain tumours. They include astrocytic gliomas, oligodendrocytic gliomas, ependymomas and gliomas with mixed cell populations. Each glioma type consists of both low-grade and malignant atypical varieties. The low-grade tumours occur predominantly in children and young adults, and the malignant forms in older people. The presenting symptoms are epileptic seizures, headache and mental confusion. Focal neurological symptoms and findings, such as hemiparesis, are mostly associated with the malignant forms. Magnetic resonance imaging (MRI) scan of the brain with and without gadolinium contrast demonstrates the tumour. However, stereotactic biopsy or surgical resection is necessary to obtain the correct pathological diagnosis, except for diffuse pontine astrocytomas, which have an unmistakeable imaging appearance and for which biopsy has substantial risks. Treatment depends on the pathological diagnosis. Complete surgical resection may be curative for low-grade tumours. Postoperative radiotherapy is recommended for partially resected tumours. Most malignant gliomas require aggressive combination therapy with radiotherapy and chemotherapy after maximal surgery. The standard initial regimens are nitrosourea-based chemotherapies, such as carmustine alone, a combination of procarbazine, lomustine and vincristine, or a combination of thioguanine, procarbazine, lomustine and hydroxycarbamide (hydroxyurea). Unfortunately, the prognosis of malignant gliomas is generally poor despite aggressive treatment, because of their infiltrative nature and high relapse rate.

Treatment of recurrent malignant supratentorial gliomas with ifosfamide, carboplatin and etoposide: a phase II study

Thirty-six patients previously treated with surgery, radiation therapy and chemotherapy with a nitrosourea for malignant supratentorial gliomas received a combination of ifosfamide, carboplatin and etoposide (ICE) at tumour progression. Carboplatin and etoposide were both given at a dose of 75-100 mg/m2/day for 3 days, whereas ifosfamide doses ranged from 750 mg/m2/day to 1500 mg/m2/ day for 3 days, according to haematological tolerance. Treatment was repeated every 4 weeks. A minimum of three courses was required to evaluate the response unless the patient had rapid tumour progression. Grade III and IV haematological toxicity occurred in 15 patients (42%) and was lethal in one patient. Grade II hepatic toxicity was observed in one patient. Five complete (CR) and five partial responses (PR) were noted. 9 patients had stable disease (SD) after a minimum of three courses. CR + PR + SD was 53% (19/36). The median time to tumour progression (MTTP) was 13 weeks. Median survival (MST) was 29 weeks (44 weeks for R + S patients and 17 weeks for patients with progressing disease). This study suggests that the ICE combination is active in recurrent supratentorial malignant gliomas after failure of surgery, radiation therapy and chemotherapy, but at the cost of substantial haematological toxicity.

Effectiveness of Early Chemotherapy Treatment in Anaplastic Astrocytoma Patients

There are limited data in the literature concerning chemotherapy trials for the treatment of anaplastic astrocytomas. Forty-one anaplastic astrocytoma patients, operated on during the period 1988 to 1993 at the Neurological Institute of Milan, received 4-5 cycles of chemotherapy (BCNU + cisplatin), subsequently radiotherapy (median dose 56.5 Gy), and finally a second-line chemotherapy protocol at recurrence (procarbazine, vincristine, lomustine). The aim of the study was to evaluate the effectiveness of the planned protocol, considering the time to tumor progression and the survival time. The group of anaplastic astrocytoma patients was compared with a homogeneous group of 39 anaplastic astrocytoma patients treated only with radiotherapy after surgery. The median time to tumor progression of patients on the protocol was 24.5 months. The median survival time for anaplastic astrocytoma patients treated with our scheduled protocol or only with radiotherapy was 38.8 and 21 months, respectively. However, our data need to be confirmed by large randomized clinical studies.

Role of stereotactic biopsy in multifocal brain lesions: considerations on 100 consecutive cases

One hundred patients affected by multifocal brain lesions were investigated by serial stereotactic biopsy. Systemic diseases and primary neoplasms elsewhere were previously ruled out. The histological diagnosis obtained in this series comprises malignant gliomas in 37% of patients; primary non-Hodgkin's brain lymphoma in 15%; metastatic brain tumours in 15% (no evidence of the primary tumour at the time of stereotactic surgery); low grade gliomas in 12%; infective diseases in 10% (including brain abscesses and multifocal viral encephalitis); and ischaemic lesions in 6%. In addition, two patients with germinomas, two with primitive neuroepithelial tumours, two with multiple telangiectases, and one with a teratoma were also included in this series. Histological findings obtained by stereotactic procedures guided the choice of treatment, avoiding the risks of blind treatments. Indications and future perspectives for stereotactic surgery in multifocal brain lesions are discussed with emphasis on advances in diagnostic and therapeutic tools.

Carboplatin combined with carmustine and etoposide in the treatment of glioblastoma

The aim of this study was to verify the tolerability and efficacy of therapeutic chemotherapy protocols, employing different combinations of cisplatin, carboplatin, etoposide and carmustine in primary glioblastoma patients. The purpose was focused on 2 end points: the response index to treatment, the TTP (tumor progression) and the ST (survival time). Eighty-four out of a group of 99 consecutive glioblastoma patients, entered this study. Patients were divided into 4 disparate treatment groups: (A) BCNU alone; (B) CDDP + VP-16; (C) CBDCA + BCNU; (D) CBDCA + BCNU + VP-16. The effectiveness and the TTP of the protocols differed, but differences were not statistically significant. Data concerning platinum treatment compare favorably with the best literature results. At 18 months more than half the carboplatin-treated patients are alive. Moreover these patients had a significantly longer ST than those treated with BCNU. We conclude that platinum-based chemotherapy has a beneficial effect on glial tumors.