Combined intra-arterial chemotherapy and irradiation of malignant gliomas

miR-126 Suppresses Invasion and Migration of Malignant Glioma by Targeting Mature T Cell Proliferation 1 (MTCP1)

BACKGROUND The aim of this study was to assess the utility of miR-126 in promoting malignant glioma progression and determine if miR-126 might be a target for malignant glioma treatment. MATERIAL AND METHODS The expression of miR-126 in malignant glioma tissues and cells was detected by reverse transcription polymerase chain reaction (RT-PCR). Western blot analysis was used to detect changes in protein levels. Transwell assay was applied to assess the migration and invasion in vitro. Luciferase reporter assay was used to confirm the binding of miR-126 and mature T cell proliferation 1 (MTCP1). A nude mouse tumor model was used to assess the molecular mechanism in vivo. RESULTS The expression level of miR-126 in patients with stage III~IV malignant glioma was significant lower than that in patients with stage I~II. In different malignant glioma cell lines, the expression was significantly reduced in U87MG. Compared with the control mimics group, the expression of MTCP1 was significantly decreased. The results of Transwell assay showed that the invasiveness and migration in the miR-126 mimics group was significantly lower than in the control mimics groups. miR-126 mimics did not affect luciferase activity in the Mut-miR-126/MTCP1 group, while miR-126 mimics reduced luciferase activity by 54% in the Wt-miR-126/MTCP1 group. The results of invasion showed that the invasion ability in the miR-126 inhibitor group was significantly increased compared with that in the normal control (NC) group, while the invasion and migration abilities in the MTCP1 siRNA group were significantly increased. After 6 weeks, the tumor volume in the miR-126 inhibitor group was significantly increased, while that in the MTCP1 siRNA group was significantly decreased. CONCLUSIONS miR-126 inhibits the migration of malignant glioma cells by inhibiting MTCP1.

Intra-arterial chemotherapy of primary brain tumors

Intra-arterial (IA) chemotherapy is a form of regional delivery to brain tumors, designed to enhance the intra-tumoral concentrations of a given drug, in comparison with the intravenous route. Drugs that are likely to benefit from IA delivery have a rapid systemic clearance and include carmustine and other nitrosoureas, cisplatin, carboplatin, etoposide, and methotrexate. Clinical studies have demonstrated activity of IA chemotherapy approaches for low- and high-grade gliomas, and for cerebral lymphomas. However, a survival benefit for IA drug delivery, in comparison with intravenous administration, has not been proven in phase III trials. The technique is limited by the potential for significant vascular and neurologic toxicity, including visual loss, stroke, and leukoencephalopathy. More recent studies suggest that toxicity can be reduced by the use of carboplatin- and methotrexate-based regimens. Further clinical studies will be needed to determine the appropriate role for IA chemotherapy in the treatment of primary brain tumors.

Stereotactically Guided Fractionated Re-irradiation in Recurrent Glioblastoma Multiforme

PURPOSE

To assess the feasibility, efficacy and toxicity of fractionated stereotactic radiotherapy in the treatment of recurrent glioblastoma multiforme.

PATIENTS AND METHODS

From January 1995 to July 2003, 53 patients with histologically proven glioblastoma multiforme were treated at recurrence with fractionated stereotactic radiation therapy. A median dose of 36 Gy using a median fractionation of 5 x 2 Gy/week was applied.

RESULTS

Median overall survival was 21 months, and median overall survival from the time point of re-irradiation was 8 months. The median time interval between primary and secondary radiation therapy was 10 months. In this patient population, no variables predicting longer overall survival could be determined. However, neurosurgical resection at relapse was associated with increased survival after re-irradiation (p=0.04), but left progression-free survival unaltered. Treatment was well-tolerated and no severe toxicities developed.

CONCLUSION

Stereotactically guided fractionated re-irradiation is a safe and effective treatment modality in selected cases of recurring glioblastoma multiforme. Since this is not a randomized study, further evaluation in larger patient collectives is warranted. Also, based on recent results of radiochemotherapy in the treatment of primary glioblastoma multiforme, concomitant chemotherapy at relapse might be considered in the future.

Interstitial chemotherapy plus systemic chemotherapy for glioblastoma patients: improved survival in sequential studies

We investigated the efficacy of 3 different systemic chemotherapy regimes in 122 patients with histologically confirmed glioblastoma, KPS > 60, age < 65. Locoregional chemotherapy was delivered to 22 patients from all three systemic chemotherapy groups. Chemotherapy was given before and during radiotherapy, which was the same for all patients consisting of unconventional fractionation with a break between courses. Survival (Kaplan-Meier) was significantly longer in the subgroup receiving cisplatinum plus BCNU compared to those receiving cisplatinum plus etoposide or carboplatinum plus BCNU with median survival time 21.5 months, 15 months and 15 months respectively (log rank test p = 0.01). Survival was also significantly longer in patients who received locoregional therapy compared to those who received only systemic chemotherapy (21 vs 15 months, p = 0.01). Univariate analysis showed that age, postoperative Karnofsky status and extent of resection were not predictive of survival in the series, although there were trends to better outcome in younger patients and those undergoing total/subtotal resection. Age, systemic chemotherapy type and interstitial treatment were included in a multivariate analysis, and both locoregional treatment and chemotherapy with cisplatinum plus BCNU were significantly predictive of survival [P = 0.01]. These encouraging preliminary results suggest that further trials with locoregional and systemic therapy prior to radiotherapy are worth pursuing.

A retrospective study of the value of chemotherapy as adjuvant therapy to surgery and radiotherapy in grade 3 and 4 gliomas

The aim of this retrospective study was to evaluate the effect of adjuvant chemotherapy among patients < 55 years of age with anaplastic gliomas (historical grade 3, n = 85) with four cycles 4 weeks apart of 160 mg carmustine (BCNU) infused into the internal carotid artery, combined with vincristine 2 mg and procarbazine 50 mg x 3 for 1 week (i.a.BCNU-PV) versus no adjuvant chemotherapy. In glioblastomas (histological grade 4, n = 257) the same chemotherapy was evaluated versus two cycles 4 weeks apart of 160 mg lomustine (CCNU) orally instead of BCNU, combined with vincristine and procarbazine (PCV) versus no chemotherapy. All patients in both groups received radiotherapy. Among glioblastoma patients < 55 years of age there was a significant (P = 0.03), but moderately increased survival in the i.a.BCNU-PV group versus the two other arms that did not differ from each other. This difference could be explained by an uneven distribution of prognostic factors, especially age group (< 50 years versus 50-54 years) in favour of the i.a.BCNU-PV group. In anaplastic gliomas, the median survival in the i.a.BCNU-PV group was 80 months versus 25 months for the no chemotherapy arm (P = 0.004). No significant differences in the distribution of prognostic factors were found between the two therapy arms. We suggest that the role of adjuvant chemotherapy in glioblastomas is unclear, while i.a.BCNU-PV as adjuvant chemotherapy among patients < 55 years of age and with anaplastic gliomas increased survival markedly.

High-dose conformal radiotherapy influenced the pattern of failure but did not improve survival in glioblastoma multiforme

BACKGROUND AND PURPOSE

Although glioblastoma multiforme is clearly radiation-resistant, there is evidence of a dose-dependent response relationship. The purpose of the study was to evaluate the impact of higher dose by rotational multileaf collimator (MLC) conformal radiation therapy.

MATERIALS AND METHODS

From 1984 to 1995, 38 consecutive cases with intracranial glioblastoma multiforme were treated using the rotational MLC conformal therapy. There were 25 men and 13 women with a median age of 47 years (12-73 years, mean 46.5 years). Median Karnofsky performance score was 80 (30-100, mean 78.2). Median tumor volume was 64 cc (8-800 cc, mean 110.3 cc). All underwent surgical intervention (only biopsy in 1, partial resection in 13, subtotal resection in 21, and gross total resection in 3). Radiation dose to was 60 to 80 Gy (median 68.5 Gy, mean 68.3 Gy) in 21 patients treated before 1990 and 90 Gy in the 17 patients thereafter. Biweekly i.v. chemotherapy was also administered for both arms.

RESULTS

The 1-year, 2-year, 5-year, and 10-year overall survival rates were 75%, 42%, 20%, and 15%, respectively. Univariate analysis showed the initial tumor volume, residual tumor volume, and Karnofsky performance score were statistically significant factors for survival. Only the residual tumor volume was statistically significant by multivariate analysis. The 5-year survival rate of patients with residual tumors of 5 cc or less in volume was as good as 37%. Survival of the 90-Gy Group appeared inferior to that of the Low-Dose Group, though no statistical difference was seen (the 3-year survival was 40% vs. 22%). Local failure was observed in 16 of the 19 recurrences in the Low-Dose Group, whereas it was observed in only 4 of the 13 recurrences in the 90-Gy Group. The difference in pattern of failure was statistically significant. Two patients of the High-Dose Group developed radiation necrosis and one died of it.

CONCLUSIONS

The high-dose conformal radiotherapy did not improve survival in the disease, but did change the pattern of failure.

Prognostic factors in malignant gliomas with special reference to intra-arterial chemotherapy

Survival was analyzed in 173 patients with malignant gliomas to study the importance of possible pretreatment prognostic factors. Seventy-nine of these patients received preirradiation intra-arterial chemotherapy with BCNU combined with vincristine intravenously and procarbazine orally; the others received only postoperative whole-brain irradiation. To judge by univariate and multivariate analyses the most important pretreatment prognostic factors were histology, corticosteroid dependency, pretreatment performance status and frontal lobe location of the tumors. Patients with anaplastic astrocytoma, not corticosteroid-dependent, with pretreatment performance status of 0-2 and with a frontal lobe location of the tumor seemed to benefit most from preirradiation chemotherapy.

Pre-radiation chemotherapy in glioma patients with poor prognostic factors

Nineteen patients in an age group from 56-67 years (mean age 62.5 years) with histologically verified glioblastoma multiforme were treated with chemotherapy consisting of two cycles of oral CCNU, intravenous vincristine and oral procarbazine prior to radiation therapy. Ten of the patients had stable disease, monitored by CT scan and neurological examination, and received whole brain radiation. The median survival was 12 months. Nine patients who had progressive disease during chemotherapy did not receive radiation treatment and were put on palliative treatment with dexamethasone. This group had a median survival of 3 months. The median survival in all of the 19 patients who entered the study was 9 months which was comparable to the survival of 56 patients with glioblastoma multiforme who, in a retrospective study, received post-operative radiotherapy. The most important factor predicting survival was steroid-dependency after surgery.