These results provide a rationale for the clinical evaluation of Vgamma9Vdelta2 T lymphocytes in HCC and CRC.

Human Vc9Vd2 T lymphocytes can be activated by nonpeptidic antigens such as the mevalonate pathway-derived isopentenyl pyrophosphate or synthetic phosphoantigen such as bromohydrin pyrophosphate. They display a strong cytotoxic activity against several tumor types, including hepatocellular carcinoma (HCC). Little is known about the mechanisms underlying Vc9Vd2 T-cell recognition of tumor cells, but there is strong evidence that activating NK receptors play a role in cd T-cell cytotoxicity. In this study, we showed that the two NK receptors DNAX accessory molecule-1 (DNAM-1) and CD96 were expressed by Vc9Vd2 T cells. The ligands Nectin-like-5 specific of both DNAM-1 and CD96, and also Nectin-2, an additional ligand of DNAM-1, were present on all HCC cell lines analyzed. Furthermore, we demonstrated by mAb-mediated masking experiments that cytotoxicity against HCC cells as well as IFN-c production in cd T cells were dependent on DNAM-1. Our experiments indicated that Nectin-like-5 but not Nectin-2 was involved in DNAM-1-dependent cd T-cell functions. We did not reveal a role for CD96 in the killing of HCC cells. Finally, we showed by combined mAb-mediated blockade that DNAM-1 and NKG2D could cooperate in the cell lysis of HCC.

Hepatocellular carcinoma (HCC) and colorectal carcinoma with hepatic metastases (mCRC) are cancers with poor prognosis and limited therapeutic options. New approaches are needed and adoptive immunotherapy with Vgamma9Vdelta2 T lymphocytes represents an attractive strategy. Indeed, Vgamma9Vdelta2 T cells were shown to exhibit efficient lytic activity against various human tumor cell lines, and in vitro Vgamma9Vdelta2 T expansion protocol based on single phosphoantigen stimulation could be easily performed for healthy donors. However, a low proliferative response of Vgamma9Vdelta2 T cells was observed in about half of the cancer patients, leading to an important limitation in the development of Vgamma9Vdelta2 T cell-based immunotherapy. Here, for the first time in the context of cancer patients, Vgamma9Vdelta2 T cell expansions were performed by co-culturing peripheral blood mononuclear cell (PBMCs) with autologous dendritic cells (DCs) pretreated with aminobisphosphonate zoledronate. For patients not responding to the conventional culture protocol, co-culture of PBMC with zoledronate-pretreated DCs induced strong cell expansion and allowed reaching a minimal rate of purity of 70% of Vgamma9Vdelta2 T cells. The potent immunostimulatory activity of zoledronate-treated DCs was associated with higher amount of isopentenyl pyrophosphate (IPP) in the culture and was correlated with better ability to activate Vgamma9Vdelta2 T cells as measured by IFN-gamma production. Moreover, we demonstrated that the cytotoxic level of Vgamma9Vdelta2 T cells against freshly autologous tumor cells isolated from patients could be significantly increased by pretreating the tumor cells with zoledronate. Thus, this method of generating Vgamma9Vdelta2 T cells leads eligible for Vgamma9Vdelta2 T cell adoptive immunotherapy the HCC and mCRC patients.

No abstract

Summary Two patients with proven 5-fluorouracil (5-FU)-associated cardiotoxicity were treated with the specific thymidylate synthase inhibitor raltitrexed safely, without evidence of cardiotoxicity. Raltitrexed might be an alternative for patients with advanced colorectal cancer and 5-FU-associated cardiotoxicity. 5-FU cardiotoxicity is not due to the antineoplastic mechanisms via thymidilate synthase.Keywords: 5-fluorouracil; cardiotoxicity; raltitrexed; colorectal neoplasms 5-Fluorouracil (5-FU)-associated cardiotoxicity was recognized 18 years after its first clinical use, after symptoms of chest pain typical of angina pectoris, in patients treated with 5-FU (Dent and McColl, 1965). Estimates of its incidence have been given with a range of 1.6% in larger series (Labianca et al, 1982) and up to 10% in smaller cohorts (Collins and Weiden, 1987). 5-FU should be discontinued in the case of cardiotoxicity to avoid the development of serious or fatal cardiac damage (Anand, 1994). However, the arsenal of effective antineoplastic compounds for the treatment of colorectal cancer is limited, and the identification of a drug that may be safely given to patients with cardiac toxicity after 5-FU administration is important. Here, we report the successful administration of raltitrexed (Zeneca, Macclesfield, Cheshire, UK), a new specific thymidylate synthase inhibitor, in two patients with 5-FU-induced cardiotoxicity. PATIENTS AND METHODS Case 1A 58-year-old female without any history of cardiovascular disease presented at our institution with lung and liver metastases of a sigmoid adenocarcinoma. She had received three cycles of weekly folinic acid 500 mg m-2 as a 2-h infusion and 5-FU 500 mg m-2 as an i.v. bolus in the middle of the folinic acid infusion repeated for 6 weeks followed by a 2-week rest period. This therapy was tolerated well without any cardiac toxicity. When the tumour progressed, treatment with high-dose 5-FU 2600 mg m-2 given as a weekly 24-h infusion plus folinic acid 500 mg m-2 as a 2-h infusion before 5-FU was initiated. Approximately 22 h after the start of the 5-FU infusion the patient complained of dyspnoea and retrosternal pain and the 5-FU infusion was stopped. The blood pressure was 80/60 mmHg and the heart rate was regular with 100 beats per min. The ECG obtained after onset of symptoms revealed non-specific ST segment elevation in the anterior and posterior leads with a normalization after 24 h (Figures 1 and 2). Serial measurements of serum cardiac enzymes were normal. One week later, the patient was given the same 5-FU/folinic acid regimen and also received isosorbide dinitrate, molsidomine and acetylsalicylic acid. Approximately 10 h after the start of the 5-FU infusion, the patient complained of dyspnoea and retrosternal chest pain. The ECG revealed temporary changes similar to those observed a week earlier. Again, serial determination of serum cardiac enzyme levels remained unchanged. An echocardiogram was normal except for a localized apical hypokinesia. The global ejection fraction w...