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Background:
Ketogenic diets (KDs) or short-term fasting are popular trends amongst supportive approaches for cancer patients. Beta-hydroxybutyrate (3-OHB) is the main physiological ketone body, whose concentration can reach plasma levels of 2–6 mM during KDs or fasting. The impact of 3-OHB on the biology of tumor cells described so far is contradictory. Therefore, we investigated the effect of a physiological concentration of 3 mM 3-OHB on metabolism, proliferation, and viability of breast cancer (BC) cells in vitro.
Methods:
Seven different human BC cell lines (BT20, BT474, HBL100, MCF-7, MDA-MB 231, MDA-MB 468, and T47D) were cultured in medium with 5 mM glucose in the presence of 3 mM 3-OHB at mild hypoxia (5% oxygen) or normoxia (21% oxygen). Metabolic profiling was performed by quantification of the turnover of glucose, lactate, and 3-OHB and by Seahorse metabolic flux analysis. Expression of key enzymes of ketolysis as well as the main monocarboxylic acid transporter MCT2 and the glucose-transporter GLUT1 was analyzed by RT-qPCR and Western blotting. The effect of 3-OHB on short- and long-term cell proliferation as well as chemo- and radiosensitivity were also analyzed.
Results:
3-OHB significantly changed the oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in BT20 cells resulting in a more oxidative energetic phenotype. MCF-7 and MDA-MB 468 cells had increased ECAR only in response to 3-OHB, while the other three cell types remained uninfluenced. All cells expressed MCT2 and GLUT1, thus being able to uptake the metabolites. The consumption of 3-OHB was not strongly linked to mRNA overexpression of key enzymes of ketolysis and did not correlate with lactate production and glucose consumption. Neither 3-OHB nor acetoacetate did interfere with proliferation. Further, 3-OHB incubation did not modify the response of the tested BC cell lines to chemotherapy or radiation.
Conclusions:
We found that a physiological level of 3-OHB can change the energetic profile of some BC cell lines. However, 3-OHB failed to influence different biologic processes in these cells, e.g., cell proliferation and the response to common breast cancer chemotherapy and radiotherapy. Thus, we have no evidence that 3-OHB generally influences the biology of breast cancer cells in vitro.
In tissue engineering, the generation and functional maintenance of dense voluminous tissues is mainly restricted due to insufficient nutrient supply. Larger three-dimensional constructs, which exceed the nutrient diffusion limit become necrotic and/or apoptotic in long-term culture if not provided with an appropriate vascularization. Here, we established protocols for the generation of a pre-vascularized biological scaffold with intact arterio-venous capillary loops from rat intestine, which is decellularized under preservation of the feeding and draining vascular tree. Vessel integrity was proven by marker expression, media/blood reflow and endothelial LDL uptake. In vitro maintenance persisted up to 7 weeks in a bioreactor system allowing a stepwise reconstruction of fully vascularized human tissues and successful in vivo implantation for up to 4 weeks, although with time-dependent decrease of cell viability. The vascularization of the construct lead to a 1.5× increase in cellular drug release compared to a conventional static culture in vitro. For the first time, we performed proof-of-concept studies demonstrating that 3D tissues can be maintained within a miniaturized vascularized scaffold in vitro and successfully implanted after re-anastomosis to the intrinsic blood circulation in vivo. We hypothesize that this technology could serve as a powerful platform technology in tissue engineering and regenerative medicine.
Weltweit steigt die Anzahl der morbid adipösen Menschen stetig an. Dies führt zu einer Zunahme der medizinischen und psychosozialen Komplikationen des Einzelnen und der gesundheitsökonomischen Belastung der Gesellschaft. Kosteneffektive und langfristige Therapiekonzepte sind dringend notwendig. Die bariatrische Chirurgie stellt die einzige Therapieoption der morbiden Adipositas dar, mit der eine langfristige Gewichtsreduktion und damit eine signifikante Verbesserung der adipositasassoziierten Begleiterkrankungen erreicht werden kann. Die Mechanismen der Gewichtsabnahme im Rahmen einer bariatrischen Operation sind noch nicht ausreichend erforscht und verstanden. Hinweise Das Geruchsempfinden, als wichtiger Bestandteil der Nahrungsauswahl, könnte durch eine Veränderung in Folge einer bariatrischen Operation einen Einfluss auf die Gewichtsreduktion haben.
In der vorliegenden Arbeit wurde mittels der Sniffin´sticks das Geruchsempfinden morbid adipöser Menschen in Zusammenhang mit einer bariatrischen Operation (RYGB, n=15 vs. SG, n=15) untersucht (0-1-6-12-24 Wochen). Als Kontrollgruppe dienten morbid adipöse Probanden unter konservativer Therapie (n=12).
Der Ausgangs-BMI der SG-Gruppe (56,04 ± 7,09 kg/m2) war im Vergleich zur RYGB- Gruppe (48,71 ± 6,49 kg/m2) und der konservativ behandelten Gruppe (50,35 ± 6,78 kg/m2) signifikant höher (p= 0,011*). Das Ausmaß der Gewichtsabnahme der beiden operierten Gruppen zeigte keine signifikanten Unterschiede (p=0,87). Die konservativ behandelte Gruppe nahm praktisch kein Gewicht ab.
Der Ausgangs-SDI-Wert der SG-Gruppe (27,09 ± 3,93) war im Vergleich zur RYGB- Gruppe (32,61 ± 3,64) und zur konservativ behandelten Gruppe (32,15 ± 5,32) signifikant niedriger. Die SG-Gruppe erreichte nach 6 Monaten SDI-Werte von 31,06 ± 3,49, was einen signifikanten Anstieg darstellt (p=0,040*).
Die SG-Gruppe hatte anfangs signifikant niedrigere Schwellenwerte als die RYGB- Gruppe (p=0,0050**). Auch im Vergleich zu den Patienten der konservativ behandelten Gruppe erzielte die SG-Gruppe präoperativ signifikant niedrigere Schwellenwerte (p=0,0026).
Ein signifikanter Anstieg der Schwellenwerte innerhalb von 6 Monaten zeigte sich nur in der SG-Gruppe (p=0,00061***). Die Mittelwerte lagen präoperativ bei 4,71 ± 1,31 und nach sechs Monaten bei 7,29 ± 2,11. Die RYGB-Gruppe erzielte präoperativ Mittelwerte von 6,82 ± 1,85 und nach sechs Monaten von 7,8 ± 1,41, was ein knapp nicht signifikanter Anstieg ist (p=0,054). Im Vergleich der Diskriminationswerte zeigte sich lediglich ein knapp signifikanter Anstieg der konservativ behandelten Gruppe (p=0,035*). Alle weiteren Werte waren nicht signifikant. Bezüglich der Identifikationswerte konnten keine signifikanten Veränderungen beobachtet werden.
Mit abnehmendem BMI nahm der SDI-Wert der SG-Gruppe signifikant zu (p=0,0074**), was bei der RYGB-Gruppe nicht zutraf (p=0,20).
Die Ergebnisse dieser Arbeit zeigen, dass das Geruchsempfinden durch einen wesentlichen Gewichtsverlust an sich nicht beeinflusst wird. Die Daten deuten darauf hin, dass sich die Riechfunktion nach einer Sleeve Gastrectomy im Vergleich zu einer Roux-Y gastric bypass verbessert. Es scheint folglich Mechanismen zu geben, die von der Operationsmethode abhängen. In der Zukunft sind weitere Forschungsanstrengungen nötig, um die Mechanismen der Gewichtsabnahme nach bariatrischer Operation und insbesondere die Veränderungen des Geruchsempfindens in Abhängigkeit des Operationsverfahrens besser verstehen zu können.
In der vorliegenden Arbeit " Inzidenz und Outcome von Teratomen des Ovars - eine retrospektive Datenanalyse " werden die Ergebnisse einer retrospektiven Datenanalyse für ein Zeitfenster von 10 Jahren diskutiert.
Gegenstand war die Auswertung der Patientenakten aller ovariellen Neubildungen, welche in den Jahren 2005-2015 in der Abteilung für Kinderchirurgie der chirurgischen Universitätsklinik Würzburg (Chirurgische Klinik I) behandelt wurden. Die Filterung der Datenbanken nach den erforderlichen Kriterien ergab einen Patientenstamm von 28 Fällen.
Zentrale Untersuchungsparameter stellten das Patientenalter zum Erkrankungszeitpunkt, die diagnoseweisenden Symptome, die präoperative Diagnostik, die Wahl der Operationsmethode, der postoperative Verlauf der Krankengeschichte, das Nachsorgeprogramm sowie die Untersuchung auf rezidivierende Prozesse dar.
Die gewonnenen Ergebnisse des betrachteten Patientenstamms wurden objektiv zusammengefasst, auf mögliche Gesetzmäßigkeiten untersucht, präsentiert und durch Grafiken bildlich veranschaulicht.
In der Diskussion erfolgte die Einordnung in die aktuelle wissenschaftliche Studienlage und der Vergleich mit themenspezifischen bekannten Erkenntnissen und Literatur.
The number of bariatric surgeries being performed worldwide has markedly risen. While the improvement in obesity-associated comorbidities after bariatric surgery is well-established, very little is known about its impact on cancer risk. The peripheral lymphocyte micronucleus test is a widely used method for the monitoring of chromosomal damage levels in vivo, and micronucleus frequency positively correlates with cancer risk. Therefore, the aim of this study was to compare the micronucleus frequency before and after bariatric surgery in obese subjects. Peripheral blood mononuclear cells were collected from 45 obese subjects before and at two time-points after bariatric surgery (6 and 12 months) to assess spontaneous micronucleus frequency. Consistent with the increased cancer risk previously shown, bariatric surgery-induced weight loss led to a significant reduction in lymphocyte micronucleus frequency after 12 months. Interestingly, comorbidities such as type 2 diabetes mellitus and metabolic syndrome further seemed to have an impact on the lymphocyte micronucleus frequency. Our findings may indicate a successful reduction of cancer risk in patients following weight loss caused by bariatric surgery.
Background:
The treatment strategies for colorectal cancer located in the right side of the colon have changed dramatically during the last decade. Due to the introduction of complete mesocolic excision (CME) with central ligation of the vessels and systematic lymph node dissection, the long-term survival of affected patients has increased significantly. It has also been proposed that right-sided colon resection can be performed laparoscopically with the same extent of resection and equal long-term results.
Methods:
A retrospective evaluation of a prospectively expanded database on right-sided colorectal cancer or adenoma treated at the University Hospital of Wuerzburg between 2009 and 2016 was performed. All patients underwent CME. This data was analyzed alone and in comparison to the published data describing laparoscopic right-sided colon resection for colon cancer.
Results:
The database contains 279 patients, who underwent right-sided colon resection due to colorectal cancer or colorectal adenoma (255 open; 24 laparoscopic). Operation data (time, length of stay, time on ICU) was equal or superior to laparoscopy, which is comparable to the published results. Surprisingly, the surrogate parameter for correct CME (the number of removed lymph nodes) was significantly higher in the open group. In a subgroup analysis only including patients who were feasible for laparoscopic resection and had been operated with an open procedure by an experienced surgeon, operation time was significantly shorter and the number of removed lymph nodes is significantly higher in the open group.
Conclusion:
So far, several studies demonstrate that laparoscopic right-sided colon resection is comparable to open resection. Our data suggests that a consequent CME during an open operation leads to significantly more removed lymph nodes than in laparoscopically resected patients and in several so far published data of open control groups from Europe. Further prospective randomized trials comparing the long-term outcome are urgently needed before laparoscopy for right-sided colon resection can be recommended ubiquitously.
TNF-like weak inducer of apoptosis (TWEAK) and inhibition of protein synthesis with cycloheximide (CHX) sensitize for poly(I:C)-induced cell death. Notably, although CHX preferentially enhanced poly(I:C)-induced apoptosis, TWEAK enhanced primarily poly(I:C)-induced necroptosis. Both sensitizers of poly(I:C)-induced cell death, however, showed no major effect on proinflammatory poly(I:C) signaling. Analysis of a panel of HeLa-RIPK3 variants lacking TRADD, RIPK1, FADD, or caspase-8 expression revealed furthermore similarities and differences in the way how poly(I:C)/TWEAK, TNF, and TRAIL utilize these molecules for signaling. RIPK1 turned out to be essential for poly(I:C)/TWEAK-induced caspase-8-mediated apoptosis but was dispensable for this response in TNF and TRAIL signaling. TRADD-RIPK1-double deficiency differentially affected poly(I:C)-triggered gene induction but abrogated gene induction by TNF completely. FADD deficiency abrogated TRAIL- but not TNF- and poly(I:C)-induced necroptosis, whereas TRADD elicited protective activity against all three death inducers. A general protective activity against poly(I:C)-, TRAIL-, and TNF-induced cell death was also observed in FLIPL and FLIPS transfectrants.