| 1. |
- Hansen, Lasse Tengbjerg, et al.
(författare)
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DNA Repair Rate and Etoposide (VP16) Resistance of Tumor Cell Subpopulations derived from a Single Human Small Cell Lung Cancer
- 2003
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Ingår i: Lung Cancer. - : Elsevier. - 0169-5002. ; 40:2, s. 157-64
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Tidskriftsartikel (refereegranskat)abstract
- Two human small cell lung cancer (SCLC) subpopulations, CPH 54A, and CPH 54B, established from the same patient tumor by in vitro cloning, were investigated. The tumor was classified as intermediate-type SCLC. The cellular sensitivity to ionizing radiation (IR) was previously determined in the two sublines both in vivo and in vitro. Here we measured the etoposide (VP16) sensitivity together with the induction and repair of VP16- and IR-induced DNA double-strand breaks (DSBs). The two subpopulations were found to differ significantly in sensitivity to VP16, with the radioresistant 54B subline also being VP16 resistant. In order to explain the VP16 resistant phenotype several mechanisms where considered. The p53 status, P-glycoprotein, MRP, topoisomerase IIα, and Mre11 protein levels, as well as growth kinetics, provided no explanations of the observed VP16 resistance. In contrast, a significant difference in repair of both VP16- and IR-induced DSBs, together with a difference in the levels of the DSB repair proteins DNA-dependent protein kinase (DNA-PKcs) and RAD51 was observed. The VP16- and radioresistant 54B subline exhibited a pronounced higher repair rate of DSBs and higher protein levels of both DNA-PKcs and RAD51 compared with the sensitive 54A subline. We suggest, that different DSB repair rates among tumor cell subpopulations of individual SCLC tumors may be a major determinant for the variation in clinical treatment effect observed in human SCLC tumors of identical histological subtype.
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| 2. |
- Henriksson, Roger, et al.
(författare)
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Impact of therapy on quality of life, neurocognitive function and their correlates in glioblastoma multiforme : a review
- 2011
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Ingår i: Journal of Neuro-Oncology. - Boston : Nijhoff. - 0167-594X .- 1573-7373. ; 104:3, s. 639-646
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Forskningsöversikt (refereegranskat)abstract
- The maintenance of quality of life (QoL) in patients with high-grade glioma is an important endpoint during treatment, particularly in those with glioblastoma multiforme (GBM) given its dismal prognosis despite limited advances in standard therapy. It has proven difficult to identify new therapies that extend survival in patients with recurrent GBM, so one of the primary aims of new therapies is to reduce morbidity, restore or preserve neurologic functions, and the capacity to perform daily activities. Apart from temozolomide, cytotoxic chemotherapeutic agents do not appear to significantly impact response or survival, but produce toxicity that is likely to negatively impact QoL. New biological agents, such as bevacizumab, can induce a clinically meaningful proportion of durable responses among patients with recurrent GBM with an acceptable safety profile. Emerging evidence suggests that bevacizumab produces an improvement or preservation of neurocognitive function in GBM patients, suggestive of QoL improvement, in most poor-prognosis patients who would otherwise be expected to show a sudden and rapid deterioration in QoL.
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| 3. |
- Malmström, Annika, 1957-, et al.
(författare)
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ABCB1 single-nucleotide variants and survival in patients with glioblastoma treated with radiotherapy concomitant with temozolomide
- 2020
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Ingår i: The Pharmacogenomics Journal. - : Nature Publishing Group. - 1470-269X .- 1473-1150. ; 20:2, s. 213-219
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Tidskriftsartikel (refereegranskat)abstract
- Standard treatment for glioblastoma (GBM) patients is surgery and radiochemotherapy (RCT) with temozolomide (TMZ). TMZ is a substrate for ABCB1, a transmembrane drug transporter. It has been suggested that survival for GBM patients receiving TMZ is influenced by different single-nucleotide variants (SNV) of ABCB1. We therefore examined SNV:s of ABCB1, namely 1199Gamp;gt;A, 1236Camp;gt;T, 2677Gamp;gt;T/A, and 3435Camp;gt;T and correlated to survival for GBM patients receiving RCT. In a pilot cohort (97 patients) a significant correlation to survival was found for SNV 1199Gamp;gt;A, with median OS for variant G/G patients being 18.2 months versus 11.5 months for A/G (p = 0.012). We found no correlation to survival for the other SNV:s. We then expanded the cohort to 179 patients (expanded cohort) and also included a confirmatory cohort (49 patients) focusing on SNV 1199Gamp;gt;A. Median OS for G/G versus A/G plus A/A was 15.7 and 11.5 months, respectively (p = 0.085) for the expanded cohort and 13.8 versus 16.8 months (p = 0.19) for the confirmatory. In conclusion, in patients with GBM receiving RCT with TMZ, no correlation with survival was found for the SNV:s 1236Camp;gt;T, 2677Gamp;gt;T/A, and 3435Camp;gt;T of ABCB1. Although the SNV 1199Gamp;gt;A might have some impact, a clinically significant role could not be confirmed.
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| 4. |
- Malmström, Annika, et al.
(författare)
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Postoperative neoadjuvant temozolomide before radiotherapy versus standard radiotherapy in patients 60 years or younger with anaplastic astrocytoma or glioblastoma: a randomized trial
- 2017
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Ingår i: Acta Oncologica. - : TAYLOR & FRANCIS LTD. - 0284-186X .- 1651-226X. ; 56:12, s. 1776-1785
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: A pilot study of temozolomide (TMZ) given before radiotherapy (RT) for anaplastic astrocytoma (AA) and glioblastoma (GBM) resulted in prolonged survival compared to historical controls receiving RT alone. We therefore investigated neoadjuvant TMZ (NeoTMZ) in a randomized trial. During enrollment, concomitant and adjuvant radio-chemotherapy with TMZ became standard treatment. The trial was amended to include concurrent TMZ.Patients and methods: Patients, after surgery for GBM or AA, age 60 years and performance status (PS) 0-2, were randomized to either 2-3 cycles of TMZ, 200mg/m(2) days 1-5 every 28 days, followed by RT 60Gy in 30 fractions or RT only. Patients without progressive disease after two TMZ cycles, received the third cycle. From March 2005, TMZ 75mg/m(2) was administered daily concomitant with RT. TMZ was recommended first-line treatment at progression. Primary endpoint was overall survival and secondary safety.Results: The study closed prematurely after enrolling 144 patients, 103 with GBM and 41 with AA. Median age was 53 years (range 24-60) and 89 (62%) were male. PS was 0-1 for 133 (92%) patients, 53 (37%) had complete surgical resection and 18 (12%) biopsy. Ninety-two (64%) received TMZ concomitant with RT. Seventy-two (50%) were randomized to neoadjuvant treatment. For the overall study population survival was 20.3 months for RT and 17.7 months for NeoTMZ (p=.76), this not reaching the primary objective. For the preplanned subgroup analysis, we found that NeoTMZ AA patients had a median survival of 95.1 months compared to 35.2 months for RT (p=.022). For patients with GBM, no difference in survival was observed (p=.10). MGMT and IDH status affected outcome.Conclusions: No advantage of NeoTMZ was noted for the overall study population or subgroup of GBM, while NeoTMZ resulted in 5 years longer median survival for patients diagnosed as AA.
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