In a phase III trial in patients with advanced, well-differentiated, progressive pancreatic neuroendocrine tumors, sunitinib 37.5 mg/day improved investigator-assessed progression-free survival (PFS) ...versus placebo (11.4 versus 5.5 months; HR, 0.42; P < 0.001). Here, we present PFS using retrospective blinded independent central review (BICR) and final median overall survival (OS), including an assessment highlighting the impact of patient crossover from placebo to sunitinib.
In this randomized, double-blind, placebo-controlled study, cross-sectional imaging from patients was evaluated retrospectively by blinded third-party radiologists using a two-reader, two-time-point lock, followed by a sequential locked-read, batch-mode paradigm. OS was summarized using the Kaplan–Meier method and Cox proportional hazards model. Crossover-adjusted OS effect was derived using rank-preserving structural failure time (RPSFT) analyses.
Of 171 randomized patients (sunitinib, n = 86; placebo, n = 85), 160 (94%) had complete scan sets/time points. By BICR, median (95% confidence interval CI) PFS was 12.6 (11.1–20.6) months for sunitinib and 5.8 (3.8–7.2) months for placebo (HR, 0.32; 95% CI 0.18–0.55; P = 0.000015). Five years after study closure, median (95% CI) OS was 38.6 (25.6–56.4) months for sunitinib and 29.1 (16.4–36.8) months for placebo (HR, 0.73; 95% CI 0.50–1.06; P = 0.094), with 69% of placebo patients having crossed over to sunitinib. RPSFT analysis confirmed an OS benefit for sunitinib.
BICR confirmed the doubling of PFS with sunitinib compared with placebo. Although the observed median OS improved by nearly 10 months, the effect estimate did not reach statistical significance, potentially due to crossover from placebo to sunitinib.
NCT00428597.
Rapamycin and its derivatives (CCI-779, RAD001 and AP23576) are immunosuppressor macrolides that block mTOR (mammalian target of rapamycin) functions and yield antiproliferative activity in a variety ...of malignancies. Molecular characterization of upstream and downstream mTOR signaling pathways is thought to allow a better selection of rapamycin-sensitive tumours. For instance, a loss of PTEN functions results in Akt phosphorylation, cell growth and proliferation; circumstances that can be blocked using rapamycin derivatives. From recent studies, rapamycin derivatives appear to display a safe toxicity profile with skin rashes and mucositis being prominent and dose-limiting. Sporadic activity with no evidence of dose–effect relationship has been reported. Evidence suggests that rapamycin derivatives could induce G1–S cell cycle delay and eventually apoptosis depending on inner cellular characteristics of tumour cells. Surrogate molecular markers that could be used to monitor biological effects of rapamycin derivatives and narrow down biologically active doses in patients, such as the phosphorylation of P70S6K or expression of cyclin D1 and caspase 3, are currently evaluated. Since apoptosis induced by rapamycin is blocked by BCL-2, strategies aimed at detecting human tumours that express BCL-2 and other anti-apoptotic proteins might allow identification of rapamycin-resistant tumours. Finally, we discuss current and future placements of rapamycin derivatives and related translational research into novel therapeutic strategies against cancer.
Inhibition of tumor growth factor-β (TGF-β) receptor type I potentiated the activity of sorafenib in preclinical models of hepatocellular carcinoma (HCC). Galunisertib is a small-molecule selective ...inhibitor of TGF-β1 receptor type I, which demonstrated activity in a phase 2 trial as second-line HCC treatment.
The combination of galunisertib and sorafenib (400 mg BID) was tested in patients with advanced HCC and Child-Pugh A liver function without prior systemic therapy. Galunisertib dose was administered 80 or 150 mg b.i.d. orally for 14 days every 28 days in safety lead-in cohorts; in the expansion cohort, all patients received galunisertib 150 mg b.i.d. Objectives included time-to-tumor progression, changes in circulating alpha fetoprotein and TGF-β1, safety, overall survival (OS), response rate, and pharmacokinetics (PK).
Patients (n = 47) were enrolled from 5 non-Asian countries; 3 and 44 patients received the 80 mg and 150 mg b.i.d. doses of galunisertib, respectively. The pharmacokinetics and safety profiles were consistent with monotherapy of each drug. For the 150 mg b.i.d. galunisertib cohort, the median time-to-tumor progression was 4.1 months; the median OS was 18.8 months. A partial response was seen in 2 patients, stable disease in 21, and progressive disease in 13. TGF-β1 responders (decrease of >20% from baseline) vs nonresponders had longer OS (22.8 vs 12.0 months, P = 0.038).
The combination of galunisertib and sorafenib showed acceptable safety and a prolonged OS outcome.
Highlights • Preclinical research identified c-MET as a promising target for head and neck cancer. • c-MET activation mediates important functions in both malignant and stromal cells. • Aberrant ...signalling includes mutations, amplifications, crosstalk, and overexpression. • Immunohistochemical c-MET overexpression may have prognostic and predictive value. • c-MET inhibition may overcome resistance to EGFR tyrosine kinase inhibitors
In head and neck squamous cell carcinoma (HNSCC), data from studies using checkpoint-inhibiting antibodies that target programmed death 1 (PD-1) or its ligand the programmed death ligand 1 (PD-L1) ...demonstrated outstanding clinical activity. Translational investigations also suggested some correlations between therapeutic response and PD-L1 expression in tumor tissue. We comprehensively summarize results that have evaluated PD-L1 expression in HNSCC. We discuss flaws and strength of current PD-1/PD-L1 detection, quantification methods and the evaluation of PD-L1 as a prognostic and theragnostic biomarker. Understanding tumor microenvironment may help understanding resistance to checkpoint inhibitors, designing clinical trials that can exploit drug combinations.
The proof of principle that a drug targeting mTOR can improve survival has been obtained recently from a large randomised trial using temsirolimus as a first-line therapy in patients with advanced ...poor prognostic renal cell carcinoma. Consistent data have recently shown the important role of the PI3K/AKT/mTOR signalling pathway in the regulation of crucial metabolic and mitotic functions of cancer cells and endothelial cells allowing a better understanding of the role of mTOR in controlling cancer cell proliferation and survival as well as tumour angiogenesis. As a result, rapamycin derivatives (rapalogues) that block mTOR/Raptor complex 1 were shown to exert direct antiproliferative effects against endometrial cancers, in which cancer cells frequently lose PTEN function as well as mantle cell lymphomas, in which cancer cell proliferation appears to be driven primarily by cyclin D1 overexpression. The overall antitumour effects of rapalogues in renal cell carcinoma appear to be more complex with tumour growth inhibition resulting from direct G1/S cell cycle blockage and/or apoptotic effects in carcinoma cells along with the inhibition of downstream signalling of the HIF1alpha-induced VEGF/VEGFR autocrine loop in endothelial cells shutting down the maintenance of tumour angiogenesis. Despite extensive cognitive researches, it is difficult to appraise which of those mechanisms is predominant in patients. This review focuses on mechanisms of action of rapalogues focusing on antitumour effects in patients with renal cell carcinoma.
In the study we present results of stable isotope analysis (δ18O, δ13C) of two stalagmites (SPD-1 and SPD-2) from Strašna peć Cave, situated on Dugi otok Island in the Central Adriatic region. The ...growth interval of the speleothems based on U-Th dating covers the period from 4.4 ka to 1.5 ka. Both speleothems show frequent δ18O and δ13C fluctuations with similar average values (δ18O value of -4‰ for both speleothems; and average value of δ13C-8.5‰ and −8.8‰, respectively). In order to reconstruct the Holocene climatic conditions in the Eastern Adriatic, the speleothem isotopic record is discussed and compared with other Holocene records. They reveal periods of drought which occurred at 4.3–4 ka and around 3.5 ka, with relatively wet phases between. From 3 ka, there is a general trend towards dryness as evidentiated by the relatively high δ18O values of -3.5‰ to -2.5‰ recorded in speleothem SPD-1. There is distinct trend of drying during the Roman Warm Period and further toward the Dark Age Cold Period (DACP) with shorter periods of wetter conditions. These changes coincide well with the other records, thus revealing regional events along the Eastern Adriatic.