Abstract P3-10-24: Not presented

This abstract was not presented at the conference.

Citation Format: Gasparini E, Bisagni A, Di Cicilia R, Kuhn E, Falco G, Ferrari G, Foroni M, Tamagnini I, Bassano C, Ragazzi M, Gardini G, Cecchi F, Hembrough T, Bisagni G. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-10-24.

Effect of the serine proteases inhibitor gabexate mesylate (GM) on the activity of gemcitabine (G) in cell lines of pancreatic cancer (PC)

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Background: Negligible advances for PC treatment have been done over the last decade and G remains the standard. Proteolitic degradation of extracellular matrix (ECM) is essential for early local invasion, metastasis and desmoplastic reaction characterizing PC. Differently from MMPs, the serine proteases (uPA and TAT) action is earlier and larger, degradating not only ECM, but also basement membrane, and activating trypsin, plasmin, angiogenesis via TGF-β1 and proliferation via PAR-2. GM is an inhibitor of u-PA,TAT, trypsin and plasmin, used in Italy and Japan for prophylaxis of acute pancreatitis after ERCP. In a previous study, GM demonstrated antinvasion and antimetastatic activity. Study aim: to evaluate if GM increases G efficacy on pancreatic cancer cell line. Methods: In vitro study of phenotypic effects of GM and G in poor differentiated PANC-1 PC cell line using:1) Cell vitality test (Trypan blu);2) Invasion test (Matrigel invasion assay);3) Cell cycle analysis (cytofluorimeter);4) Antiangiogenic test (tube formation assay in extracellular matrix using E.A.hy926 endothelial cells with matrigel). Different doses of G and GM (100,200,250,500 μM;1mM) alone or combined (concomitant or sequential) have been tested vs controls (PANC-1 without any treatment). All tests have been done in triplicate. Results: G alone (250 μM) decreases invasion by 40% (±5,6%) and cell vitality by 15% (±1,3%.). GM alone (100 μM) decreases invasion by 30% (±4,6%.) but 1mM is needed for similar vitality decrease. GM+G together are detrimental vs G alone while sequential treatment (GM before G with or without 24 hours of interval) enhances G activity. GM (200 μM) and G (250 μM) in immediate sequence show better results decreasing ability of invasion by 75% (±8,3%). Cell vitality is better inhibited from GM (100)/G (250) 24 h-delayed sequence by 28% (±3,8%). Combined treatment mainly blocks cells in G1 phase of cell cycle (5%±0,5%) vs controls. Concerning antiangiogenic assay, the administration of G alone is ineffective to inhibit angiogenesis, while pre-treatment with GM results in a strong anti-angiogenic effect. Conclusions: Association of GM to G could represent a new effective approach to inhibit invasion, angiogenesis and growth in pancreatic cancer.

No significant financial relationships to disclose.

GEMOX as first-line chemotherapy in advanced pancreatic cancer (APC): A monoinstitutional experience

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Background: To date, gemcitabine (GEM) remains the cornerstone of chemotherapy (CHT) for APC. According to GERCOR and GISCAD phase III trials the combination of GEM and oxaliplatin (GEMOX) has proven superior to GEM alone in terms of response rate (RR), time to progression (TTP) and clinical benefit rate (CBR). Methods: We conducted a retrospective analysis on 19 patients (pts) affected with histologically-confirmed APC, in order to determine the impact of GEMOX as first-line chemotherapy in terms of objective responses (OR) and TTP, using the Kaplan-Meier method. Among the 19 pts considered there were 15 males and 4 females (median age at diagnosis of 60.84 yrs; ECOG 0–2). The staging, according to AJCC criteria, was: IIB in 1 case, III in 5 cases and IV in the 13 remaning cases. The only metastatic site was the liver (in 13/19 pts). Ten of the 19 pts underwent surgical treatment prior to CHT: 2 radically resected (R0) subsequently treated with GEMOX after recurrence, 4 with positive margins (R1) and 4 surgically palliated. All pts received GEM 1000 mg/m2/d1 + oxaliplatin 100 mg/m2/d2 every 2 weeks. The median number of cycles was 5.89. Results: Among the 19 pts, 3 had a partial response (PR, 15.69%), 6 had stable disease (SD, 31.57%); no complete response was observed and 10 pts had progressive disease (PD, 52.63%). The overall disease control rate (DCR: PR + SD) was 47.37% while the OR were 15.69%. The median survival observed was 9.03 months (95% C.I. 5.15–12.91) and the median TTP was 6.13 months (95% C.I. 2.81–9.46). The main toxicities were: leucopenia, piastrinopenia, diarrhoea, nausea, fever and peripheral neuropathy; 3 pts discontinued the treatment due to grade 3–4 neurotoxicity. Conclusions: In our experience GEMOX gives an improved control of APC in terms of OR and TTP, with acceptable toxicity. The OS is in accordance to literature as well as the other data.

No significant financial relationships to disclose.