Abstract LB-A01: Molecular subgroup analysis of a randomized trial (EORTC 26082-22081) testing temsirolimus and radiation therapy versus chemoradiotherapy with temozolomide in patients with newly diagnosed glioblastoma without methylation of the MGMT gene promoter

Background:

Preclinical data indicate activity of mammalian target of rapamycin (mTOR) inhibitors, as well as synergistic activity together with radiotherapy in glioblastoma. The aim of this non-comparative randomized phase II trial (NCT01019434) was to assess the therapeutic activity of the mTOR inhibitor temsirolimus, in patients with newly diagnosed glioblastoma with unmethylated O6 methylguanine-DNA-methyltransferase (MGMT) promoter. These patients are in particular need for new treatment options as they derive little if any benefit from the currently standard temozolomide treatment.

Methods:

Patients were registered and their tumors were centrally reviewed and tested for the MGMT status. Participation to the trial was offered to patients with histologically confirmed glioblastoma harboring an unmethylated MGMT promoter. Patients (n = 111) were randomized 1:1 between standard of care of radiotherapy (60 Gy; 5 times 2 Gy per week) plus concomitant and six cycles of maintenance temozolomide (TMZ/RT/→TMZ) or radiotherapy plus weekly temsirolimus at 25 mg flat dose to be continued until progression or undue toxicity. Primary endpoint was overall survival at 12 months (OS12). For a representative subgroup of 88 patients sufficient tumor tissue was available for pre-specified post hoc analyses of a panel of markers considered to be relevant for the activity of mTOR inhibition in order to identify a subgroup of patients potentially sensitive to temsirolimus.

Findings:

Both therapies were properly administered with a median of 13 weeks of maintenance temsirolimus or 4 cycles of TMZ. In the intention to treat population OS12 was 69.6% [95% CI (55.8-79.9) in the temsirolimus arm and 72.2% [95% CI (58.2, 82.2)] in the temozolomide arm [HR = 1.16 95% CI (0.77-1.76), p = 0.47]. In multivariable prognostic analyses of clinical and molecular factors, the phosphorylation status of mTOR [HR = 0.13, 95% CI (0.04-0.47), p = 0.002], but no clinical factor was a significant predictor in the temsirolimus arm. There was a significant interaction between treatment and phosphorylated mTOR (p-mTOR) (p = 0.047). The median overall survival in the temsirolimus group was 17.8 months (CI, 14.1-28.0) for patients with p-mTOR positive tumors and 13.11 (CI, 9.7-15.1) in the negative subgroup. In the RT/TMZ→TMZ control arm the median survival in the p-mTOR positive group was 14.0 months (CI, 9.6-19.6) and 16.5 months (CI, 9.5-18.8) in the p-mTOR negative subgroup.

Interpretation:

The therapeutic activity of temsirolimus is too low in the whole cohort of patients with newly diagnosed glioblastoma with an unmethylated MGMT promoter. However, the phosphorylation status of mTOR may identify a subgroup that benefits from temsirolimus, while the same treatment may be detrimental to patients with p-mTOR negative tumors.

Funding:

Pfizer provided an unrestricted academic grant. Molecular subgroup analysis was funded by the Swiss National Science Foundation (FN31003A-138116 to M.E.H).

Previously presented in part at ASCO 2014 (abstract #2003)

Citation Format: Monika E. Hegi, Thierry Gorlia, Pierre Bady, Michael Platten, Martin J. van den Bent, Martin JB Taphoorn, Jonathan Steuve, Alba A. Brandes, Marie-France Hamou, Markus Kosch, Vassilis Golfinopoulos, Mario Campone, Patrick Roth, Benoit Lhermitte, Roger Stupp, Gianfranco Pesce, Wolfgang Wick. Molecular subgroup analysis of a randomized trial (EORTC 26082-22081) testing temsirolimus and radiation therapy versus chemoradiotherapy with temozolomide in patients with newly diagnosed glioblastoma without methylation of the MGMT gene promoter. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr LB-A01.

Metabolic stress boosts humoral responses in vivo independently of inflammasome and inflammatory reaction

Adjuvant formulations boost humoral responses by acting through several, yet incompletely elucidated pathways. In this study, we show that oligomycin or 5-aminoimidazole-4-carboxamide-1-β-D-ribonucleoside (AICAR) enhances Ab production when coinjected with T cell-dependent Ags. Oligomycin and AICAR lead to intracellular ATP reduction, suggesting that metabolic stress could be sensed by immune cells and leads to increased humoral responses. AICAR promotes IL-4 and IL-21 by naive Th cells but does not affect dendritic cell activation/maturation in vitro or in vivo. Accordingly, the adjuvant effect of AICAR or oligomycin does not require MyD88 or caspase-1 expression in vivo. Because AICAR is well tolerated in humans, this compound could represent a novel and safe adjuvant promoting humoral responses in vivo with a minimal reactogenicity.

DiC14-amidine cationic liposomes stimulate myeloid dendritic cells through Toll-like receptor 4

DiC14-amidine cationic liposomes were recently shown to promote Th1 responses when mixed with allergen. To further define the mode of action of diC14-amidine as potential vaccine adjuvant, we characterized its effects on mouse and human myeloid dendritic cells (DC). First, we observed that, as compared with two other cationic liposomes, only diC14-amidine liposomes induced the production of IL-12p40 and TNF-alpha by mouse bone marrow-derived DC. DiC14-amidine liposomes also activated human DC, as shown by synthesis of IL-12p40 and TNF-alpha, accumulation of IL-6, IFN-beta and CXCL10 mRNA, and up-regulation of membrane expression of CD80 and CD86. DC stimulation by diC14-amidine liposomes was associated with activation of NF-kappaB, ERK1/2, JNK and p38 MAP kinases. Finally, we demonstrated in mouse and human cells that diC14-amidine liposomes use Toll-like receptor 4 to elicit both MyD88-dependent and Toll/IL-1R-containing adaptor inducing interferon IFN-beta (TRIF)-dependent responses.

In vivo and in vitro immunomodulation of Der p 1 allergen-specific response by Lactobacillus plantarum bacteria

BACKGROUND

Lactic acid bacteria (LAB) were reported to reduce some allergic manifestations in mice and humans but their impact on the aeroallergen-dependent immune mechanisms is still debated.

OBJECTIVE

The potential capacities of Lactobacillus plantarum NCIMB8826 to reduce the allergic response induced by Der p 1, the major house dust mite allergen of Dermatophagoides pteronyssinus, were evaluated in vivo and in vitro. Methods First, the effect of the intranasal co-administration of LAB and purified Der p 1 allergen before a sensitization protocol was evaluated. The allergen-specific antibody and cellular responses as well as airway inflammation were measured. Second, the impact of LAB on the cytokine profile of spleens cells from Der p 1-sensitized mice was assessed. Third, upon stimulation with LAB, the levels of cytokine produced by dendritic cells derived from the bone marrow (BMDCs) of wild-type, Toll-like receptor 2 (TLR2)-, TLR4- and MyD88-KO mice were compared. Results The co-application of L. plantarum and Der p 1 induced a T-helper type 1 (Th1)-biased allergen-specific IgG response, the absence of specific IgE response and favoured the production of INF-gamma upon allergen re-stimulation. Moreover, the previous LAB administration reduced the development of bronchoalveolar lavage eosinophilia usually induced by aerosol exposure. Additionally, the studied LAB strain was shown to modify in vitro the cytokine level produced by Der p 1-sensitized spleen cells mainly towards a Th1 profile. Finally, L. plantarum stimulated high IL-12 and moderate IL-10 production in mouse BMDCs notably through the TLR2-, MyD88-dependent and TLR4-independent pathway.

CONCLUSION

In vivo co-administration of probiotic LAB with Der p 1 might prevent the development of the mite allergic response. The probiotic L. plantarum was shown to display in vitro therapeutic potentials for the treatment of allergy and to trigger the immune system by a TLR2- and MyD88-dependent signalling pathway.

[Laboratory tests in acute pancreatitis (author's transl)]

Blood and urine samples of 37 patients hospitalized with a proved diagnosis of acute pancreatitis are reviewed. Value of serum glutamic transaminase activity is the best discriminator between biliary and non biliary pancreatitis (p less than 0.0025). Hypercoagulability is very often observed but there is no correlation between the importance of this abnormality and the severity of the disease. No single specific marker of the prognostic is identified.

[Parenteral nutrition in gastro-intestinal surgery (author's transl)]

Forty-two postoperative patients received by parenteral route on 24 hours a total of 2,610 calories by means of a simultaneous infusion of 1,500 ml Trivé 1000 and 1,500 ml 10% invert sugar through a central venous line. Of those 42 cases 12 had peritonitis with 7 of them an enteric fistula, 18 underwent an extensive bowel resection and 12 suffered malnutrition secondary to their primary pathology. The average duration of parenteral nutrition was 13 days and the average hospital stay 27 days. No major metabolic derangement was noted except for a temporary transient elevation of SGOT and AF. A systematic bacteriological study of the perfusion lines disclosed an associated morbidity of about 6%. We are convinced that with the used solutions the postoperative catabolism can be managed successfully and that the association of aminoacids, lipids and glucides as used by us facilitates, nursing care.