Nitroxyl radicals were used as functionalizing agents during the free radical postreactor modification process of polyolefins carried out in the melt. The 4‐hydroxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (HO‐TEMPO) and the 4‐benzoyloxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (BzO‐TEMPO) free radicals were successfully grafted onto a polyethylene‐based material (ethylene‐co‐1‐octene copolymer) by coupling reaction with polymer macroradicals; these last were formed by H‐abstraction through peroxide addition. The macromolecular structure of the functionalized polyolefins was assessed by 1H‐NMR, FTIR spectroscopy, and SEC measurements which were used to evidence the grafting site, to evaluate the grafting level and to highlight the occurrence of chain extension through crosslinking side reactions. Indeed the use of proper model compounds allowed the preparation of accurate FTIR calibration curves for the quantitative determination of the functionalization degree. Besides the high temperature SEC analysis highlighted that this fast and simple coupling reaction between macroradicals and nitroxyl free radicals grants the grafting of functionalities onto the polyolefin backbone by contemporarily preventing the side reactions liable of the structure and MW modification of the pristine polymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

BACKGROUND To determine the safety and maximum-tolerated dose of concurrent sunitinib and image-guided radiotherapy (IGRT) followed by maintenance sunitinib in oligometastastic patients. METHODS: Eligible patients had 1 to 5 sites of metastatic cancer measuring ≤6 cm. The most common treatment sites were bone, liver, and lung. Patients were treated with concurrent sunitinib (Day 1 through Day 28) and IGRT (40-50 Gy in 10 fractions starting on Day 8) followed by maintenance sunitinib (50 mg daily, 4 weeks on/2 weeks off starting on Day 43). The starting dose was sunitinib 25 mg and IGRT 40 Gy. Doses were escalated in a ping-pong design with incremental increases in either sunitinib or IGRT. RESULTS: Twenty-one patients with 36 metastatic lesions were enrolled, with a median follow-up of 10 months. No dose limiting toxicities (DLT) were noted at dose levels 1 or 2 (SU 37.5 mg/RT 40 Gy). One of 10 patients at dose level 3 (SU 37.5 mg/RT 50 Gy) and 2 of 5 patients at dose level 4 (SU 50 mg/RT 50 Gy) experienced DLTs comprising grade 4 myelosuppression and grade 3 nausea. At last follow-up, 8 patients are alive without evidence of progression. The 1-year local, progression-free, and overall survival were 85%, 44%, and 75%, respectively. CONCLUSIONS: Addition of SU (25 to 37.5 mg) to IGRT is tolerable in patients with oligome-tastases, without potentiation of RT toxicity. On the basis of promising antitumor responses observed with this novel combination, a multi-institutional phase 2 trial using SU 37.5 mg/RT 50 Gy is ongoing.

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Summary Whole exome sequencing of cutaneous melanoma has led to the detection of P29 mutations in RAC1 in 5–9% of samples, but the role of RAC1 P29 mutations in melanoma biology remains unclear. Using reverse phase protein array analysis to examine the changes in protein/phospho-protein expression, we identified cyclin B1, PD-L1, Ets-1, and Syk as being selectively upregulated with RAC1 P29S expression and downregulated with RAC1 P29S depletion. Using the melanoma patient samples in TCGA, we found PD-L1 expression to be significantly increased in RAC1 P29S patients compared to RAC1 WT as well as other RAC1 mutants. The finding that PD-L1 is upregulated suggests that oncogenic RAC1 P29S may promote suppression of the antitumor immune response. This is a new insight into the biological function of RAC1 P29S mutations with potential clinical implications as PD-L1 is a candidate biomarker for increased benefit from treatment with anti-PD1 or anti-PD-L1 antibodies.