240 research outputs found
Cell-in-cell phenomenon: leukocyte engulfment by non-tumorigenic cells and cancer cell lines
Background
Research on cell-in-cell (CIC) phenomena, including entosis, emperipolesis and cannibalism, and their biological implications has increased in recent years. Homotypic and heterotypic engulfment of various target cells by numerous types of host cells has been studied in vitro and in tissue sections. This work has identified proteins involved in the mechanism and uncovered evidence for CIC as a potential histopathologic predictive and prognostic marker in cancer. Our experimental study focused on non-professional phagocytosis of leukocytes.
Results
We studied the engulfment of peripheral blood mononuclear cells isolated from healthy donors by counting CIC structures. Two non-tumorigenic cell lines (BEAS-2B, SBLF-9) and two tumour cell lines (BxPC3, ICNI) served as host cells. Immune cells were live-stained and either directly co-incubated or treated with irradiation or with conventional or microwave hyperthermia. Prior to co-incubation, we determined leukocyte viability for each batch via Annexin V-FITC/propidium iodide staining.
All host cells engulfed their targets, with uptake rates ranging from 1.0% ± 0.5% in BxPC3 to 8.1% ± 5.0% in BEAS-2B. Engulfment rates of the cancer cell lines BxPC3 and ICNI (1.6% ± 0.2%) were similar to those of the primary fibroblasts SBLF-9 (1.4% ± 0.2%). We found a significant negative correlation between leukocyte viability and cell-in-cell formation rates. The engulfment rate rose when we increased the dose of radiotherapy and prolonged the impact time. Further, microwave hyperthermia induced higher leukocyte uptake than conventional hyperthermia.
Using fluorescent immunocytochemistry to descriptively study the proteins involved, we detected ring-like formations of diverse proteins around the leukocytes, consisting, among others, of α-tubulin, integrin, myosin, F-actin, and vinculin. These results suggest the involvement of actomyosin contraction, cell-cell adhesion, and the α-tubulin cytoskeleton in the engulfment process.
Conclusions
Both non-tumorigenic and cancer cells can form heterotypic CIC structures by engulfing leukocytes. Decreased viability and changes caused by microwave and X-ray irradiation trigger non-professional phagocytosis
Non-surgical oncology – Guidelines on Parenteral Nutrition, Chapter 19
Reduced nutritional state is associated with unfavourable outcomes and a lower quality of life in patients with malignancies. Patients with active tumour disease frequently have insufficient food intake. The resting energy expenditure in cancer patients can be increased, decreased, or remain unchanged compared to predicted values. Tumours may result in varying degrees of systemic pro-inflammatory processes with secondary effects on all significant metabolic pathways. Therapeutic objectives are to stabilise nutritional state with oral/enteral nutrition and parenteral nutrition (PN) and thus to prevent or reduce progressive weight loss. The maintenance or improvement of quality of life, and the increase in the effectiveness and a reduction in the side-effects of antitumor therapy are further objectives. Indications for PN in tumour patients are essentially identical to those in patients with benign illnesses, with preference given to oral or enteral nutrition when feasible. A combined nutritional concept is preferred if oral or enteral nutrition are possible but not sufficient. There are generally no accepted standards for ideal energy and nutrient intakes in oncological patients, particularly when exclusive artificial nutrition is administered. The use of PN as a general accompaniment to radiotherapy or chemotherapy is not indicated, but PN is indicated in chronic severe radiogenic enteritis or after allogenic transplantation with pronounced mucositis or GvH-related gastrointestinal damage for prolonged periods, with particular attention to increased risk of bleeding and infection. No PN is necessary in the terminal phase
Optimization of Single Voxel MR Spectroscopy Sequence Parameters and Data Analysis Methods for Thermometry in Deep Hyperthermia Treatments
Objective:
The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic resonance spectroscopy sequence (point-resolved spectroscopy) parameter optimization that enables thermometry during deep hyperthermia treatments.
Materials and Methods:
Different Lorentz peak-fitting methods and a peak finding method using singular value decomposition of a Hankel matrix were compared. Phantom measurements on organic substances (mayonnaise and pork) were performed inside the hyperthermia 1.5-T magnetic resonance imaging system for the parameter optimization study. Parameter settings such as voxel size, echo time, and flip angle were varied and investigated.
Results:
Usually all peak analyzing methods were applicable. Lorentz peak-fitting method in MATLAB proved to be the most stable regardless of the number of fitted peaks, yet the slowest method. The examinations yielded an optimal parameter combination of 8 cm3 voxel volume, 55 millisecond echo time, and a 90° excitation pulse flip angle.
Conclusion:
The Lorentz peak-fitting method in MATLAB was the most reliable peak analyzing method. Measurements in homogeneous and heterogeneous phantoms resulted in optimized parameters for the magnetic resonance spectroscopy sequence for thermometry
Quantitative, Multi-institutional Evaluation of MR Thermometry Accuracy for Deep-Pelvic MR-Hyperthermia Systems Operating in Multi-vendor MR-systems Using a New Anthropomorphic Phantom
Clinical outcome of hyperthermia depends on the achieved target temperature, therefore
target conformal heating is essential. Currently, invasive temperature probe measurements are the
gold standard for temperature monitoring, however, they only provide limited sparse data. In contrast,
magnetic resonance thermometry (MRT) provides unique capabilities to non-invasively measure
the 3D-temperature. This study investigates MRT accuracy for MR-hyperthermia hybrid systems
located at five European institutions while heating a centric or eccentric target in anthropomorphic
phantoms with pelvic and spine structures. Scatter plots, root mean square error (RMSE) and
Bland–Altman analysis were used to quantify accuracy of MRT compared to high resistance thermistor
probe measurements. For all institutions, a linear relation between MRT and thermistor probes
measurements was found with R
2
(mean ± standard deviation) of 0.97 ± 0.03 and 0.97 ± 0.02,
respectively for centric and eccentric heating targets. The RMSE was found to be 0.52 ± 0.31 ◦C and
0.30 ± 0.20 ◦C, respectively. The Bland-Altman evaluation showed a mean difference of 0.46 ± 0.20 ◦C
and 0.13 ± 0.08 ◦C, respectively. This first multi-institutional evaluation of MR-hyperthermia hybrid
systems indicates comparable device performance and good agreement between MRT and thermistor
probes measurements. This forms the basis to standardize treatments in multi-institution studies of
MR-guided hyperthermia and to elucidate thermal dose-effect relations
Targeted natural killer cell–based adoptive immunotherapy for the treatment of patients with NSCLC after radiochemotherapy: a randomized phase II clinical trial
Purpose: Non–small cell lung cancer (NSCLC) is a fatal disease with poor prognosis. A membrane-bound form of Hsp70 (mHsp70) which is selectively expressed on high-risk tumors serves as a target for mHsp70-targeting natural killer (NK) cells. Patients with advanced mHsp70-positive NSCLC may therefore benefit from a therapeutic intervention involving mHsp70-targeting NK cells. The randomized phase II clinical trial (EudraCT2008-002130-30) explores tolerability and efficacy of ex vivo–activated NK cells in patients with NSCLC after radiochemotherapy (RCT).
Patients and Methods: Patients with unresectable, mHsp70-positive NSCLC (stage IIIa/b) received 4 cycles of autologous NK cells activated ex vivo with TKD/IL2 [interventional arm (INT)] after RCT (60–70 Gy, platinum-based chemotherapy) or RCT alone [control arm (CTRL)]. The primary objective was progression-free survival (PFS), and secondary objectives were the assessment of quality of life (QoL, QLQ-LC13), toxicity, and immunobiological responses.
Results: The NK-cell therapy after RCT was well tolerated, and no differences in QoL parameters between the two study arms were detected. Estimated 1-year probabilities for PFS were 67% [95% confidence interval (CI), 19%–90%] for the INT arm and 33% (95% CI, 5%–68%) for the CTRL arm (P = 0.36, 1-sided log-rank test). Clinical responses in the INT group were associated with an increase in the prevalence of activated NK cells in their peripheral blood
Radiosensitization by BRAF inhibitor therapy—mechanism and frequency of toxicity in melanoma patients
This study shows radiosensitization by BRAF inhibitors in clinical practice and ex vivo by fluorescence in situ hybridization of chromosomal breaks. Nevertheless, radiotherapy with concomitant BRAF inhibitor therapy is feasible with an acceptable increase in toxicity. Vemurafenib is a more potent radiosensitizer than dabrafenib in both the patient study and the ex vivo experiment
F18-FDG PET/CT imaging early predicts pathologic complete response to induction chemoimmunotherapy of locally advanced head and neck cancer: preliminary single-center analysis of the checkrad-cd8 trial
Aim
In the CheckRad-CD8 trial patients with locally advanced head and neck squamous cell cancer are treated with a single cycle of induction chemo-immunotherapy (ICIT). Patients with pathological complete response (pCR) in the re-biopsy enter radioimmunotherapy. Our goal was to study the value of F-18-FDG PET/CT in the prediction of pCR after induction therapy.
Methods
Patients treated within the CheckRad-CD8 trial that additionally received FDG- PET/CT imaging at the following two time points were included: 3–14 days before (pre-ICIT) and 21–28 days after (post-ICIT) receiving ICIT. Tracer uptake in primary tumors (PT) and suspicious cervical lymph nodes (LN +) was measured using different quantitative parameters on EANM Research Ltd (EARL) accredited PET reconstructions. In addition, mean FDG uptake levels in lymphatic and hematopoietic organs were examined. Percent decrease (Δ) in FDG uptake was calculated for all parameters. Biopsy of the PT post-ICIT acquired after FDG-PET/CT served as reference. The cohort was divided in patients with pCR and residual tumor (ReTu).
Results
Thirty-one patients were included. In ROC analysis, ΔSUVmax PT performed best (AUC = 0.89) in predicting pCR (n = 17), with a decline of at least 60% (sensitivity, 0.77; specificity, 0.93). Residual SUVmax PT post-ICIT performed best in predicting ReTu (n = 14), at a cutpoint of 6.0 (AUC = 0.91; sensitivity, 0.86; specificity, 0.88). Combining two quantitative parameters (ΔSUVmax ≥ 50% and SUVmax PT post-ICIT ≤ 6.0) conferred a sensitivity of 0.81 and a specificity of 0.93 for determining pCR. Background activity in lymphatic organs or uptake in suspected cervical lymph node metastases lacked significant predictive value.
Conclusion
FDG-PET/CT can identify patients with pCR after ICIT via residual FDG uptake levels in primary tumors and the related changes compared to baseline. FDG-uptake in LN + had no predictive value.
Trial registry
ClinicalTrials.gov identifier: NCT03426657
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