Revisiting G3BP1 as a RasGAP binding protein: sensitization of tumor cells to chemotherapy by the RasGAP 317-326 sequence does not involve G3BP1.

RasGAP is a multifunctional protein that controls Ras activity and that is found in chromosomal passenger complexes. It also negatively or positively regulates apoptosis depending on the extent of its cleavage by caspase-3. RasGAP has been reported to bind to G3BP1 (RasGAP SH3-domain-binding protein 1), a protein regulating mRNA stability and stress granule formation. The region of RasGAP (amino acids 317-326) thought to bind to G3BP1 corresponds exactly to the sequence within fragment N2, a caspase-3-generated fragment of RasGAP, that mediates sensitization of tumor cells to genotoxins. While assessing the contribution of G3BP1 in the anti-cancer function of a cell-permeable peptide containing the 317-326 sequence of RasGAP (TAT-RasGAP₃₁₇₋₃₂₆), we found that, in conditions where G3BP1 and RasGAP bind to known partners, no interaction between G3BP1 and RasGAP could be detected. TAT-RasGAP₃₁₇₋₃₂₆ did not modulate binding of G3BP1 to USP10, stress granule formation or c-myc mRNA levels. Finally, TAT-RasGAP₃₁₇₋₃₂₆ was able to sensitize G3BP1 knock-out cells to cisplatin-induced apoptosis. Collectively these results indicate that G3BP1 and its putative RasGAP binding region have no functional influence on each other. Importantly, our data provide arguments against G3BP1 being a genuine RasGAP-binding partner. Hence, G3BP1-mediated signaling may not involve RasGAP.

New trends in the medical management of glioblastoma multiforme: the role of temozolomide chemotherapy.

Standard care for newly diagnosed glioblastoma multiforme (GBM) previously consisted of resection to the greatest extent feasible, followed by radiotherapy. The role of chemotherapy was controversial and its efficacy was marginal at best. Five years ago temozolomide (TMZ) was approved specifically for the treatment of recurrent malignant glioma. The role of TMZ chemotherapy administered alone or as an adjuvant therapy for newly diagnosed GBM has been evaluated in a large randomized trial whose results suggested a significant prolongation of survival following treatment. Findings of correlative molecular studies have indicated that methylguanine methyltransferase promoter methylation may be used as a predictive factor in selecting patients most likely to benefit from such treatment. In this short review the authors summarize the current role of TMZ chemotherapy in the management of GBM, with an emphasis on approved indications and practical aspects.

Adjuvant dibromodulcitol and BCNU chemotherapy in anaplastic astrocytoma: results of a randomised European Organisation for Research and Treatment of Cancer phase III study (EORTC study 26882).

BACKGROUND: In a previous randomised EORTC study on adjuvant dibromodulcitol (DBD) and bichloroethylnitrosourea (BCNU) in adults with glioblastoma multiforme (GBM) and anaplastic astrocytoma (AA), a clinically significant trend towards a longer overall survival (OS) and a progression-free survival (PFS) was observed in the subgroup of AA. The aim of the present study was to test this adjuvant regimen in a larger number of AA patients. METHODS: Continuation of the previous phase III trial for newly diagnosed AA according to the local pathologist. Patients were randomised to either radiotherapy only or to radiotherapy in combination with BCNU on day 2 and weekly DBD, followed by adjuvant DBD and BCNU in cycles of six weeks for a maximum total treatment duration of one year. OS was the primary end-point. RESULTS: Patients (193 ) with newly diagnosed AA according to local pathological assessment were randomised to radiotherapy (RT) alone (n=99), or to RT plus DBD/BCNU (n=94); 12 patients were considered not eligible. At central pathology review, over half (53%) of the locally diagnosed AA cases could not be confirmed. On intent-to-treat analysis, no statistically significant differences in OS (p=0.111) and PFS (p=0.087) were observed, median OS after RT was only 23.9 months 95% confidence interval (CI), [18.4-34.0] after RT plus DBD/BCNU 27.3 months 95% CI [21.4-46.8]. CONCLUSION: No statistically significant improvement in survival was observed after BCNU/DBD adjuvant chemotherapy in AA patients. The trend towards improved survival is consistent with previous reports. Central pathology review of grade 3 tumours remains crucial.

Occurrence of sectoral choroidal occlusive vasculopathy and retinal arteriolar embolization after superselective ophthalmic artery chemotherapy for advanced intraocular retinoblastoma.

BACKGROUND:: Superselective ophthalmic artery chemotherapy (SOAC) has recently been proposed as an alternative to intravenous chemoreduction for advanced intraocular retinoblastoma. Preliminary results appear promising in terms of tumor control and eye conservation, but little is known regarding ocular toxicity and visual prognosis. In this study, we report on the vascular adverse effects observed in our initial cohort of 13 patients. METHODS:: The charts of 13 consecutive patients with retinoblastoma who received a total of 30 injections (up to 3 injections of a single agent per patient at 3-week interval) of melphalan (0.35 mg/kg) in the ophthalmic artery between November 2008 and June 2010 were retrospectively reviewed. RetCam fundus photography and fluorescein angiography were performed at presentation and before each injection. Vision was assessed at the latest visit. RESULTS:: Enucleation and external beam radiotherapy could be avoided in all cases but one, with a mean follow-up of 7 months. Sectoral choroidal occlusive vasculopathy leading to chorioretinal atrophy was observed temporally in 2 eyes (15%) 3 weeks to 6 weeks after the beginning of SOAC and retinal arteriolar emboli in 1 eye 2 weeks after injection. There was no stroke or other clinically significant systemic side effects except a peroperative transient spasm of the internal carotid artery in one patient. Vision ranged between 20/1600 and 20/32 depending on the status of the macula. CONCLUSION:: Superselective ophthalmic artery chemotherapy was effective in all patients with no stroke or other systemic vascular complications. Unlike intravenous chemoreduction, SOAC is associated with potentially sight-threatening adverse effects, such as severe chorioretinal atrophy secondary to subacute choroidal occlusive vasculopathy or central retinal artery embolism, not to mention the risk of ophthalmic artery obstruction, which was not observed in this series. Further analysis of the risks and benefits of SOAC will define its role within the therapeutic arsenal. Meanwhile, we suggest that SOAC should be given in one eye only and restricted to advanced cases of retinoblastoma, as an alternative to enucleation and/or external beam radiotherapy.

Is chemotherapy necessary for premenopausal women with lower-risk node-positive, endocrine responsive breast cancer? 10-year update of International Breast Cancer Study Group Trial 11-93.

INTRODUCTION: International Breast Cancer Study Group (IBCSG) Trial 11-93 is the largest trial evaluating the role of the addition of chemotherapy to ovarian function suppression/ablation (OFS) and tamoxifen in premenopausal patients with endocrine-responsive early breast cancer. METHODS: IBCSG Trial 11-93 is a randomized trial comparing four cycles of adjuvant chemotherapy (AC: doxorubicin or epirubicin, plus cyclophosphamide) added to OFS and 5 years of tamoxifen versus OFS and tamoxifen without chemotherapy in premenopausal patients with node-positive, endocrine-responsive early breast cancer. There were 174 patients randomized from May 1993 to November 1998. The trial was closed before the target accrual was reached due to low accrual rate. RESULTS: Patients randomized tended to have lower risk node-positive disease and the median age was 45. After 10 years median follow up, there remains no difference between the two randomized treatment groups for disease-free (hazard ratio=1.02 (0.57-1.83); P=0.94) or overall survival (hazard ratio=0.97 (0.44-2.16); P=0.94). CONCLUSION: This trial, although small, offers no evidence that AC chemotherapy provides additional disease control for premenopausal patients with lower-risk node-positive endocrine-responsive breast cancer who receive adequate adjuvant endocrine therapy. A large trial is needed to determine whether chemotherapy adds benefit to endocrine therapy for this population.

Intravitreal chemotherapy for vitreous seeding in retinoblastoma: Recent advances and perspectives.

For decades intravitreal chemotherapy (IViC) remained virtually banished from the therapeutic armamentarium against retinoblastoma, except as a heroic attempt of salvage before enucleation in only eyes with refractory vitreous seeding. Very recently, we have initiated a reappraisal of this route of administration by (1) profiling eligibility criteria, (2) describing a safety-enhanced injection procedure, (3) adjusting the tumoricidal dose of melphalan, and (4) reporting an unprecedented efficacy in terms of tumor control of vitreous seeding. Since then, intravitreal chemotherapy is being progressively implemented worldwide with great success, but still awaits formal validation by the ongoing prospective phase II clinical trial. As far as preliminary results are concerned, IViC appears to achieve complete vitreous response in 100% of the 35 newly recruited patients irrespective of the previous treatment regimen, including external beam radiotherapy and/or intra-arterial melphalan. In other words, vitreous seeding, still considered as the major cause of primary and secondary enucleation, can now be controlled by IViC. However, sterilization of vitreous seeding does not necessarily translate into eye survival, unless the retinal source of the seeds receives concomitant therapy. In conclusion, IViC, an unsophisticated and cost-effective treatment, is about to revolutionize the eye survival prognosis of vitreous disease in advanced retinoblastoma.

Oral versus intravenous empirical antimicrobial therapy for fever in patients with granulocytopenia who are receiving cancer chemotherapy. International Antimicrobial Therapy Cooperative Group of the European Organization for Research and Treatment of Cancer.

BACKGROUND: Intravenously administered antimicrobial agents have been the standard choice for the empirical management of fever in patients with cancer and granulocytopenia. If orally administered empirical therapy is as effective as intravenous therapy, it would offer advantages such as improved quality of life and lower cost. METHODS: In a prospective, open-label, multicenter trial, we randomly assigned febrile patients with cancer who had granulocytopenia that was expected to resolve within 10 days to receive empirical therapy with either oral ciprofloxacin (750 mg twice daily) plus amoxicillin-clavulanate (625 mg three times daily) or standard daily doses of intravenous ceftriaxone plus amikacin. All patients were hospitalized until their fever resolved. The primary objective of the study was to determine whether there was equivalence between the regimens, defined as an absolute difference in the rates of success of 10 percent or less. RESULTS: Equivalence was demonstrated at the second interim analysis, and the trial was terminated after the enrollment of 353 patients. In the analysis of the 312 patients who were treated according to the protocol and who could be evaluated, treatment was successful in 86 percent of the patients in the oral-therapy group (95 percent confidence interval, 80 to 91 percent) and 84 percent of those in the intravenous-therapy group (95 percent confidence interval, 78 to 90 percent; P=0.02). The results were similar in the intention-to-treat analysis (80 percent and 77 percent, respectively; P=0.03), as were the duration of fever, the time to a change in the regimen, the reasons for such a change, the duration of therapy, and survival. The types of adverse events differed slightly between the groups but were similar in frequency. CONCLUSIONS: In low-risk patients with cancer who have fever and granulocytopenia, oral therapy with ciprofloxacin plus amoxicillin-clavulanate is as effective as intravenous therapy.

Chemotherapy in patients with advanced pancreatic cancer: too close to death?

PURPOSE: We evaluated the attitude in using chemotherapy near the end of life in advanced pancreatic adenocarcinoma (PAC). Clinical and laboratory parameters recorded at last chemotherapy administration were analyzed, in order to identify risk factors for imminent death. METHODS: Retrospective analysis of patients who underwent at least one line of palliative chemotherapy was made. Data concerning chemotherapy (regimens, lines, and date of last administration) were collected. Clinical and laboratory factors recorded at last chemotherapy administration were: performance status, presence of ascites, hemoglobin, white blood cell (WBC), platelets, total bilirubin, albumin, LDH, C-reactive protein (C-rp), and Ca 19.9. RESULTS: We analyzed 231 patients: males/females, 53/47 %; metastatic/locally advanced disease, 80/20 %; and median age, 66 years (range 32-85). All patients died due to disease progression. Median overall survival was 6.1 months (95 % CI 5.1-7.2). At the last chemotherapy delivery, performance status was 0-1 in 37 % and 2 in 63 %. Fifty-nine percent of patients received one chemotherapy line, while 32, 8, and 1 % had second-, third-, and fourth line, respectively. The interval between last chemotherapy administration and death was <4 weeks in 24 %, ≥4-12 in 47 %, and >12 in 29 %. Median survival from last chemotherapy to death was 7.5 weeks (95 % CI 6.7-8.4). In a univariate analysis, ascites, elevated WBC, bilirubin, LDH, C-rp and Ca 19.9, and reduced albumin were found to predict shorter survival; however, none of them remained significant in a multivariate analysis. CONCLUSIONS: A significant proportion of patients with advanced PAC received chemotherapy within the last month of life. The clinical and laboratory parameters recorded at last chemotherapy delivery did not predict shorter survival.

Combined radioimmunotherapy and chemotherapy of human colon carcinoma grafted in nude mice, advantages and limitations.

In order to determine if 5-fluorouracil (5FU) could potentiate the effect of radioimmunotherapy (RIT), nude mice bearing subcutaneous human colon carcinoma xenografts were treated by 1 or 2 intravenous injection(s) of subtherapeutic doses of 131I labeled F(ab')2 from anti-carcinoembryonic antigen monoclonal antibodies combined with 5 daily intraperitoneal injections of 5FU. Control mice received either 131I F(ab')2 alone, 5FU alone or no treatment. RIT alone induced significant tumor regression, while 5FU alone gave only minimal tumor growth inhibition. The combined treatment group also resulted in long-term tumor regression with tumors remaining significantly smaller than in the RIT alone group. There was however, no significant difference in tumor recurrence time between the groups treated with RIT alone or with RIT + 5FU. Myelotoxicity, the major side effect of RIT, detected by the decrease of peripheral white blood cells (WBC), was shown to be almost identical between the groups receiving only RIT or only 5FU. Surprisingly, there was no cumulative bone marrow toxicity in animals which received 5FU before RIT. Furthermore, in the latter group, the WBC levels after RIT were significantly higher than in the control group receiving only RIT. Taken together, the results demonstrate the higher therapeutic efficiency of RIT as compared to 5FU in this model. They do not show, however, that the combination of the two forms of treatment can induce longer tumor remission. Interestingly, the WBC results suggest that 5FU given before RIT can have a radioprotective effect on bone marrow, possibly by selecting radioresistant bone marrow stem cells.

Subgroup And Quality Of Life Analyses Of The Phase Iii Clinical Trial Of Novottf-100a Versus Best Standard Chemotherapy For Recurrent Glioblastoma

BACKGROUND: NovoTTF is a portable device delivering low-intensity, intermediate-frequency, electric fields using noninvasive, disposable scalp electrodes. These fields physically interfere with cell division. Preliminary studies in recurrent and newly diagnosed glioblastoma (GBM) have shown promising results. A phase III study in recurrent GBM has recently been concluded. METHODS: Adults (KPS ≥ 70%) with recurrent GBM (any recurrence) were randomized (stratified by surgery and center) to either NovoTTF administered continuously (20-24 hours/day, 7 days/week) or the best available chemotherapy (best physician choice [BPC]). Primary endpoint was overall survival (OS); 6-month progression-free survival (PFS6), 1-year survival, and QOL were secondary endpoints. RESULTS: Two hundred thirty-seven patients were randomized (28 centers in the United States and Europe) to either NovoTTF alone (120 patients) or BPC (117 patients). Patient characteristics were balanced, median age was 54 years (range, 23-80 years), median KPS was 80% (range, 50-100). One quarter had surgery for recurrence, and over half were at their second or more recurrence. A survival advantage for the device group was seen in patients treated according to protocol (median OS, 7.8 months vs. 6.1 months; n = 185; p = 0.01). Moreover, subgroup analysis in patients with better prognostic baseline characteristics (KPS ≥ 80%; age ≤ 60; 1st-3rd recurrence) demonstrated a robust survival benefit for NovoTTF patients compared to matched BPC patients (median OS, 8.8 months vs. 6.6 months; n = 110; p < 0.01). In this group, 1-year survival was 35% vs. 20% and PFS6 was 25.6% vs. 7.7%. Interestingly, in patients who failed bevacizumab prior to the trial, OS was also significantly extended by NovoTTF (4.4 months vs. 3.1 months; n = 23 vs. n = 21; p < 0.02). Quality of life was equivalent or superior in NovoTTF patients. CONCLUSIONS: NovoTTF, a noninvasive, novel cancer treatment modality shows significant therapeutic efficacy with improved quality of life. The impact of NovoTTF was more pronounced when patients with better baseline prognostic factors were treated. A large scale phase III clinical trial in newly diagnosed GBM is currently being conducted.

Carboplatin and weekly paclitaxel doublet chemotherapy compared with monotherapy in elderly patients with advanced non-small-cell lung cancer: IFCT-0501 randomised, phase 3 trial.

BACKGROUND: Platinum-based doublet chemotherapy is recommended to treat advanced non-small-cell lung cancer (NSCLC) in fit, non-elderly adults, but monotherapy is recommended for patients older than 70 years. We compared a carboplatin and paclitaxel doublet chemotherapy regimen with monotherapy in elderly patients with advanced NSCLC. METHODS: In this multicentre, open-label, phase 3, randomised trial we recruited patients aged 70-89 years with locally advanced or metastatic NSCLC and WHO performance status scores of 0-2. Patients received either four cycles (3 weeks on treatment, 1 week off treatment) of carboplatin (on day 1) plus paclitaxel (on days 1, 8, and 15) or five cycles (2 weeks on treatment, 1 week off treatment) of vinorelbine or gemcitabine monotherapy. Randomisation was done centrally with the minimisation method. The primary endpoint was overall survival, and analysis was done by intention to treat. This trial is registered, number NCT00298415. FINDINGS: 451 patients were enrolled. 226 were randomly assigned monotherapy and 225 doublet chemotherapy. Median age was 77 years and median follow-up was 30.3 months (range 8.6-45.2). Median overall survival was 10.3 months for doublet chemotherapy and 6.2 months for monotherapy (hazard ratio 0.64, 95% CI 0.52-0.78; p<0.0001); 1-year survival was 44.5% (95% CI 37.9-50.9) and 25.4% (19.9-31.3), respectively. Toxic effects were more frequent in the doublet chemotherapy group than in the monotherapy group (most frequent, decreased neutrophil count (108 [48.4%] vs 28 [12.4%]; asthenia 23 [10.3%] vs 13 [5.8%]). INTERPRETATION: Despite increased toxic effects, platinum-based doublet chemotherapy was associated with survival benefits compared with vinorelbine or gemcitabine monotherapy in elderly patients with NSCLC. We feel that the current treatment paradigm for these patients should be reconsidered. FUNDING: Intergroupe Francophone de Cancérologie Thoracique, Institut National du Cancer.

Moeglichkeiten der systemischen Therapie im metastasierten Stadium [Treatment options for chemotherapy in metastatic gastric cancer]

Die Ergebnisse mehrerer, in letzter Zeit publizierter Phase-III-Studien haben die therapeutischen Möglichkeiten in der Behandlung des metastasierten Magenkarzinoms deutlich erweitert. Die Dauerinfusion von 5-Fluorouracil (5-FU) kann ohne Verlust an Wirkung durch Capecitabin ersetzt werden, ebenso wie Cisplatin durch Oxaliplatin. Nach den Ergebnissen der REAL-2-Studie zeigt die Kombination aus Epirubicin, Oxaliplatin und Capecitabin (EOX) eine Verbesserung des Gesamtüberlebens (9,9 vs. 11,2 Monate; HR 0,8) im Vergleich zu Epirubicin, Cisplatin und 5-FU (ECF). Die Frage, ob in der First-Line-Therapie eine Dreifachkombination oder eine Zweifachkombination eingesetzt werden sollte, ist allerdings weiterhin umstritten. Die Kombination aus Irinotecan und 5-FU stellt für solche Patienten, bei denen aufgrund von Komorbiditäten eine platinfreie Therapie bevorzugt wird, eine Alternative zur Kombination Cisplatin/5-FU dar. Docetaxel, 5-FU und Cisplatin (DCF) hat sich bezüglich des Überlebens in einer randomisierten Phase-III-Studie als statistisch signifikant überlegen erwiesen, allerdings besteht eine ausgeprägte hämatologische Toxizität, welche die Anwendbarkeit insbesondere bei den häufig älteren Patienten mit einem Magenkarzinom limitiert. Randomisierte Phase-III-Studien zum Vergleich von DCF mit anderen Dreierkombinationen, wie z. B. EOX, stehen aus. Recently published results from several phase III trials have significantly increased the therapeutic options in the treatment of metastatic stomach cancer: The continuous infusion of 5-FU can be replaced by capecitabine, and cisplatin can be replaced by oxaliplatin in both cases without impairing efficacy. According to the results of the REAL-2 trial, the combination of epirubicin, oxaliplatin and capecitabine (EOX) achieved superior results for overall survival compared to epirubicin, cisplatin und 5-FU (ECF) (9.9 versus 11.2 months, HR 0.8). However, the question of whether an optimal first line therapy should include a triplet regimen or the sequential use of doublets is a matter of debate. The combination of irinotecan and 5-FU may serve as an alternative to platinum-containing regimens in patients where, due to co-morbidity, a platinum-free regimen is preferred. The 3-drug combination of docetaxel, 5-FU and cisplatin (DCF) demonstrated a statistically significant survival benefit compared to the 2-drug combination of 5-FU and cisplatin in a randomized phase III trial, although results were limited by a particularly significant hematological toxicity, which prevents its application in the large group of elderly patients with gastric cancer. Direct randomized phase III comparisons of DCF with other 3-drug combinations, such as EOX are still missing.

Long-term follow-up of high-dose chemotherapy with autologous stem-cell transplantation and response-adapted whole-brain radiotherapy for newly diagnosed primary CNS lymphoma: results of the multicenter Ostdeutsche Studiengruppe Hamatologie und Onkologie OSHO-53 phase II study.

Background We previously reported the results of a phase II study for patients with newly diagnosed primary central nervous system lymphoma treated with autologous peripheral blood stem-cell transplantation (aPBSCT) and response-adapted whole-brain radiotherapy (WBRT). Now, we update the initial results. Patients and methods From 1999 to 2004, 23 patients received high-dose methotrexate. In case of at least partial remission, high-dose busulfan/thiotepa (HD-BuTT) followed by aPBSCT was carried out. Patients refractory to induction or without complete remission after HD-BuTT received WBRT. Eight patients still alive in 2011 were contacted and Mini-Mental State Examination (MMSE) and the European Organisation for Research and Treatment of Cancer quality-of-life questionnaire (QLQ)-C30 were carried out. Results Of eight patients still alive, median follow-up is 116.9 months. Only one of nine irradiated patients is still alive with a severe neurologic deficit. In seven of eight patients treated with HD-BuTT, health condition and quality of life are excellent. MMSE and QLQ-C30 showed remarkably good results in patients who did not receive WBRT. All of them have a Karnofsky score of 90%-100%. Conclusions Follow-up shows an overall survival of 35%. In six of seven patients where WBRT could be avoided, no long-term neurotoxicity has been observed and all patients have an excellent quality of life.