Induction of reactive oxygen intermediates in human monocytes by tumour cells and their role in spontaneous monocyte cytotoxicity

The present study examined the ability of human monocytes to produce reactive oxygen intermediates after a contact with tumour cells. Monocytes generated oxygen radicals, as measured by luminol-enhanced chemiluminescence and superoxide anion production, after stimulation with the tumour, but not with untransformed, cells. The use of specific oxygen radical scavengers and inhibitors, superoxide dismutase, catalase, dimethyl sulphoxide and deferoxamine as well as the myeloperoxidase inhibitor 4-aminobenzoic acid hydrazide, indicated that chemiluminescence was dependent on the production of superoxide anion and hydroxyl radical and the presence of myeloperoxidase. The tumour cell-induced chemiluminescent response of monocytes showed different kinetics from that seen after activation of monocytes with phorbol ester. These results indicate that human monocytes can be directly stimulated by tumour cells for reactive oxygen intermediate production. Spontaneous monocyte-mediated cytotoxicity towards cancer cells was inhibited by superoxide dismutase, catalase, deferoxamine and hydrazide, implicating the role of superoxide anion, hydrogen peroxide, hydroxyl radical and hypohalite. We wish to suggest that so-called ‘spontaneous’ tumoricidal capacity of freshly isolated human monocytes may in fact be an inducible event associated with generation of reactive oxygen intermediates and perhaps other toxic mediators, resulting from a contact of monocytes with tumour cells. © 1999 Cancer Research Campaig

Properties of monocytes generated from haematopoietic CD34+ stem cells from bone marrow of colon cancer patients

Monocytes exhibit direct and indirect antitumour activities and may be potentially useful for various forms of adoptive cellular immunotherapy of cancer. However, blood is a limited source of them. This study explored whether monocytes can be obtained from bone marrow haematopoietic CD34(+) stem cells of colon cancer patients, using previously described protocol of expansion and differentiation to monocytes of cord blood-derived CD34(+) haematopoietic progenitors. Data show that in two-step cultures, the yield of cells was increased approximately 200-fold, and among these cells, up to 60 % of CD14(+) monocytes were found. They consisted of two subpopulations: CD14(++)CD16(+) and CD14(+)CD16(−), at approximately 1:1 ratio, that differed in HLA-DR expression, being higher on the former. No differences in expression of costimulatory molecules were observed, as CD80 was not detected, while CD86 expression was comparable. These CD14(+) monocytes showed the ability to present recall antigens (PPD, Candida albicans) and neoantigens expressed on tumour cells and tumour-derived microvesicles (TMV) to autologous CD3(+) T cells isolated from the peripheral blood. Monocytes also efficiently presented the immunodominant HER-2/neu(369–377) peptide (KIFGSLAFL), resulting in the generation of specific cytotoxic CD8(+) T lymphocytes (CTL). The CD14(++)CD16(+) subset exhibited enhanced cytotoxicity, though nonsignificant, towards tumour cells in vitro. These observations indicate that generation of monocytes from CD34(+) stem cells of cancer patients is feasible. To our knowledge, it is the first demonstration of such approach that may open a way to obtain autologous monocytes for alternative forms of adaptive and adoptive cellular immunotherapy of cancer

Propensity score-based analysis of long-term follow-up in patients supported with durable centrifugal left ventricular assist devices:the EUROMACS analysis

OBJECTIVES: The HeartWare HVAD (HW) and the HeartMate3 (HM3) are presently the most commonly used continuous-flow left ventricular assist devices worldwide. We compared the outcomes of patients supported with either of these 2 devices based on data from the EUROMACS (European Registry for Patients with Mechanical Circulatory Support). METHODS: A retrospective analysis of the survival and complications profile in propensity score-matched adult patients enrolled in the EUROMACS between 01 January 2016 and 01 September 2020 and supported with either an HW or HM3. Matching included demographic parameters, severity of cardiogenic shock and risk-modifying end-organ parameters that impact long-term survival. Survival on device and major postoperative adverse events were analysed. RESULTS: Following 1:1 propensity score matching, each group consisted of 361 patients. Patients were well balanced (<0.1 standardized mean difference). The median follow-up was similar in both groups [396 (interquartile range (IQR) 112-771) days for HW and 376 (IQR 100-816) days for HM3]. The 2-year survival was similar in both groups [HW: 61% 95% confidence interval (CI) (56-67%) vs HM3: 68% 95% CI (63-73%) (stratified hazard ratio for mortality: 1.13 95% CI (0.83-1.54), P = 0.435].The cumulative incidence for combined major adverse events and unexpected readmissions was similar in both groups [subdistribution hazard ratio (SHR) 1.0 (0.84-1.21), P = 0.96]. Patients in the HW group demonstrated a higher risk of device malfunction [SHR 2.44 (1.45-3.71), P < 0.001], neurological dysfunction [SHR 1.29 (1.02-1.61), P = 0.032] and intracranial bleeding [SHR 1.76 (1.13-2.70), P = 0.012]. CONCLUSIONS: Mid-term survival in both groups was similar in a propensity-matched analysis. The risk of device malfunction, neurological dysfunction and intracranial bleeding was significantly higher in HW patients

The effects of preoperative chemotherapy on isolated tumour cells in the blood and bone marrow of gastric cancer patients

Recent studies in breast cancer suggest that monitoring the isolated tumour cells (ITC) may be used as a surrogate marker to evaluate the efficacy of systemic chemotherapy. In the present study, we have investigated the effects of preoperative chemotherapy on ITC in the blood and bone marrow of patients with potentially resectable gastric cancer. After sorting out the CD45-positive cells, the presence of ITC defined as cytokeratin-positive cells was examined before and after preoperative chemotherapy. The patients received two courses of preoperative chemotherapy with cisplatin (100 mg m−2, day 1) and 5-fluorouracil (1000 mg m−2, days 1–5), administered every 28 days. Fourteen of 32 (44%) patients initially diagnosed with ITC in blood and/or bone marrow were found to be negative (responders) after preoperative chemotherapy (P<0.01). The incidence of ITC in bone marrow was also significantly (P<0.01) reduced from 97 (31 of 32) to 53% (17 of 32). The difference between patients positive for ITC in the blood before (n=7, 22%) and after (n=5, 16%) chemotherapy was statistically insignificant. The overall 3-year survival rates were 32 and 49% in the responders and non-responders, respectively (P=0.683). These data indicate that preoperative chemotherapy can reduce the incidence of ITC in patients with gastric cancer