A Th1 cytokine-enriched microenvironment enhances tumor killing by activated T cells armed with bispecific antibodies and inhibits the development of myeloid-derived suppressor cells.

In this study, we investigated whether activated T cells (ATC) armed with bispecific antibodies (aATC) can inhibits tumor growth and MDSC development in a Th1 cytokine-enriched (IL-2 and IFN-γ) microenvironment. Cytotoxicity mediated by aATC was significantly higher (P < 0.001) against breast cancer cell lines in the presence of Th1 cytokines as compared with control co-cultures. In the presence of aATC, CD33+ /CD11b+ /CD14- /HLA-DR- MDSC population was reduced significantly under both control (P < 0.03) and Th1-enriched (P < 0.036) culture conditions. Cytokine analysis in the culture supernatants showed high levels of MDSC suppressive chemokines CXCL9 and CXCL10 in Th1-enriched culture supernatants with highly significant increase (P < 0.001) in the presence of aATC. Interestingly, MDSC recovered from co-cultures without aATC showed potent ability to suppress activated T-cell-mediated cytotoxicity (P < 0.001), IFN-γ production (P < 0.01) and T-cell proliferation (P < 0.05) compared to those recovered from aATC-containing co-cultures. These data suggest that aATC can mediate enhanced killing of tumor cells and may suppress MDSC and T(reg) differentiation, and presence of Th() cytokines potentiates aATC-induced suppression of MDSC, suggesting that Th1-enriching immunotherapy may be beneficial in cancer treatment.

Systemic absorption of topical lidocaine in a bone marrow transplant recipient with hepatic sinusoidal obstruction syndrome.

PURPOSE: A case of systemic lidocaine exposure in a bone marrow transplant recipient with severe hepatic sinusoidal obstruction syndrome (SOS) receiving treatment with lidocaine patch 5% is reported. SUMMARY: A 35-year-old Caucasian man with a history of refractory acute lymphoblastic leukemia was admitted for a third allogeneic, mismatched, peripheral blood hematopoietic stem cell transplant from an unrelated donor, with a conditioning regimen that included busulfan and fludarabine. The patient was receiving treatment with lidocaine patch 5% (two patches daily, which was started five months before another hospital admission for the treatment of vincristine-related peripheral neuropathy. Baseline laboratory findings were within normal limits except for disease-related neutropenia and thrombocytopenia. Twenty days after hematopoietic stem cell transplantation (HSCT), the patient developed signs and symptoms of severe hepatic SOS. His serum alanine transaminase concentration rose from 65 IU/L at baseline to 370 IU/L, and his serum aspartate transaminase concentration rose from 32 IU/L at baseline to 871 IU/L. His total bilirubin increased to 2.8 mg/dL, and his body weight increased by 15%. An abdominal ultrasound noted ascites and hepatomegaly without reversal of blood flow. The lidocaine patch was discontinued, but the patient's condition continued to deteriorate. He died 38 days after HSCT from complications of severe hepatic SOS. CONCLUSION: A 35-year-old man developed hepatic SOS 20 days after his third HSCT. As a result of his hepatic impairment, the patient, who had been receiving lidocaine patch 5% for the treatment of neuropathic pain, experienced increased systemic exposure to lidocaine, which led to discontinuation of the patch.

Feasibility and pharmacokinetic study of infusional dexrazoxane and dose-intensive doxorubicin administered concurrently over 96 h for the treatment of advanced malignancies.

PURPOSE: Dexrazoxane administration prior to short infusion doxorubicin prevents anthracycline-related heart damage. Since delivery of doxorubicin by 96-h continuous intravenous infusion also reduces cardiac injury, we studied delivering dexrazoxane and doxorubicin concomitantly by prolonged intravenous infusion. METHODS: Patients with advanced malignancies received tandem cycles of concurrent 96-h infusions of dexrazoxane 500 mg/m2 and doxorubicin 165 mg/m2, and 24 h after completion of chemotherapy, granulocyte-colony stimulating factor (5 microg/kg) and oral levofloxacin (500 mg) were administered daily until the white blood cell count reached 10,000 microl(-1). Plasma samples were analyzed for dexrazoxane and doxorubicin concentrations. RESULTS: Ten patients were enrolled; eight patients had measurable disease. Two partial responses were observed in patients with soft-tissue sarcoma. The median number of days of granulocytopenia (<500 microl(-1)) was nine and of platelet count <20,000 microl(-1) was seven. Six patients received a single cycle because of progression (one), stable disease (four), or reversible, asymptomatic 10% decrease in cardiac ejection fraction (two). Principal grade 3/4 toxicities included hypotension (two), anorexia (four), stomatitis (four), typhlitis (two), and febrile neutropenia (seven), with documented infection (three). One death from neutropenic sepsis occurred. Dexrazoxane levels ranged from 1270 to 2800 nM, and doxorubicin levels ranged from 59.1 to 106.9 nM. CONCLUSIONS: These results suggest that tandem cycles of concurrent 96-h infusions of dexrazoxane and high-dose doxorubicin can be administered with minimal cardiac toxicity, and have activity in patients with recurrent sarcomas. However, significant non-cardiac toxicities indicate that the cardiac sparing potential of this approach would be maximized at lower dose levels of doxorubicin.