Circulating metabolites as a concept beyond tumor biology determining disease recurrence after resection of colorectal liver metastasis.

BACKGROUND: Micro-metastatic growth is considered the main source of early cancer recurrence. Nutritional and microenvironmental components are increasingly recognized to play a significant role in the liver. We explored the predictive potential of preoperative plasma metabolites for postoperative disease recurrence in colorectal cancer liver metastasis (CRCLM) patients. METHODS: All included patients (n = 71) had undergone R0 liver resection for colorectal cancer liver metastasis in the years between 2012 and 2018. Preoperative blood samples were collected and assessed for 180 metabolites using a preconfigured mass-spectrometry kit (Biocrates Absolute IDQ p180 kit). Postoperative disease-free (DFS) and overall survival (OS) were prospectively recorded. Patients that recurred within 6 months after surgery were defined as "high-risk" and, subsequently, a three-metabolite model was created which can assess DFS in our collective. RESULTS: Multiple lysophosphatidylcholines (lysoPCs) and phosphatidylcholines (PCs) significantly predicted disease recurrence within 6 months (strongest: PC aa C36:1 AUC = 0.83, p = 0.003, PC ae C34:0 AUC = 0.83, p = 0.004 and lysoPC a C18:1 AUC = 0.8, p = 0.006). High-risk patients had a median DFS of 183 days versus 522 days in low-risk population (p = 0.016, HR = 1.98 95% CI 1.16-4.35) with a 6 months recurrence rate of 47.6% versus 4.7%, outperforming routine predictors of oncological outcome. CONCLUSION: Circulating metabolites identified CRCLM patients at highest risk for 6 months disease recurrence after surgery. Our data also suggests that circulating metabolites might play a significant pathophysiological role in micro-metastatic growth and concomitant early tumor recurrences after liver resection. However, the clinical applicability and performance of this proposed metabolomic concept needs to be independently validated in future studies.

Pulmonary Embolism and Acute Psychosis, a Case Report of an Outpatient with a Mild Course of COVID-19.

The increased risk for thromboembolism in hospitalized COVID-19 patients has been communicated extensively. The fact that home quarantined patients can develop pulmonary embolism, however, has so far not been reported. Furthermore, attention should be brought to psychotic developments in COVID-19 patients. We report a 46-year-old previously healthy patient with a mild course of COVID-19, who developed a massive pulmonary embolism with right heart strain while being home quarantined. He was hospitalized and anticoagulant therapy was started. Nine days after admission, the patient appeared increasingly psychotic and suffered from hallucinations as well as paranoid thoughts. After treatment with risperidone and valproate, the patient's condition improved. At a follow-up 1 month after discharge, he was completely recovered regarding the respiratory, cardiac, and psychic situation. SARS-CoV-2 infection can not only increase the prevalence of thromboembolism in hospitalized patients but also in outpatients. COVID-19 also increases the risk of developing psychiatric reactions.

Anterograde Amnesia as a Manifestation of Acute Type A Aortic Dissection.

Objectives Memory impairment has been only rarely reported in association with acute aortic dissection type A. We report a patient with pure anterograde amnesia and memory impairment of contents occurring after the event, accompanying acute aortic dissection type A. Case Report A previously healthy 53-year-old Caucasian male was admitted because of sudden chest pain after having lifted a heavy object. Clinical examination and electrocardiogram showed no abnormalities. Since blood tests showed leukocytosis, anemia, and elevated D-dimer level, either pulmonary embolism or aortic dissection was suspected; therefore, computed tomography was suggested. The patient seemed disoriented to time, and neurologic investigation confirmed that the patient was disoriented to time; short time memory was severely impaired and concentration was reduced. An amnestic episode with anterograde amnesia was diagnosed. Computed tomography showed type A aortic dissection. A supracoronary replacement of the ascending aorta was performed. The patient was discharged on the 7th postoperative day. Three months postoperatively, the patient is clinically stable; however, amnesia for the interval between pain onset and cardiac surgery persists. Conclusions Transient amnesia, usually considered a benign syndrome, may be more common than generally recognized in aortic dissection. The suspicion for aortic dissection or other cardiovascular emergencies is substantiated when amnesia is associated with sudden onset of chest pain, leukocytosis, and elevated D-dimer levels. Computed tomography of the aorta with contrast medium is the imaging method of choice to confirm or exclude the diagnosis.

The VEGF rise in blood of bevacizumab patients is not based on tumor escape but a host-blockade of VEGF clearance.

Vascular endothelial growth factor (VEGF) has become a major target in cancer treatment as it promotes tumor angiogenesis. Therapy with anti-VEGF antibody bevacizumab reportedly induces high levels of circulating VEGF which may potentially contribute to resistance. Based on animal or computational models, mechanisms of VEGF induction by bevacizumab have been proposed but not verified in the clinical setting. Hence, we evaluated sixty patients with colorectal cancer metastases for changes in plasma VEGF during neoadjuvant/conversion and adjuvant chemotherapy with or without bevacizumab. VEGF expression was assessed in tissue sections of liver metastases. The VEGF source was investigated with in vitro cultures of tumor, endothelial cells, fibroblasts and platelets, and potential protein stabilization due to anti-VEGF therapy was addressed. A VEGF rise was observed in blood of bevacizumab patients but not in chemotherapy controls, and VEGF was found to be largely complexed by the antibody. A comparable VEGF increase occurred in the presence (neoadjuvant) and absence of the tumor (adjuvant). Accordingly, VEGF expression in tumor tissue was not determined by bevacizumab treatment. Investigations with isolated cell types did not reveal VEGF production in response to bevacizumab. However, antibody addition to endothelial cultures led to a dose-dependent blockade of VEGF internalization and hence stabilized VEGF in the supernatant. In conclusion, the VEGF rise in cancer patients treated with bevacizumab is not originating from the tumor. The accumulation of primarily host-derived VEGF in circulation can be explained by antibody interference with receptor-mediated endocytosis and protein degradation. Thus, the VEGF increase in response to bevacizumab therapy should not be regarded as a tumor escape mechanism.

Chemotherapy of colorectal liver metastases induces a rapid rise in intermediate blood monocytes which predicts treatment response.

We have previously reported that intermediate monocytes (CD14(++)/CD16(+)) were increased in colorectal cancer (CRC) patients, while the subset of pro-angiogenic TIE2-expressing monocytes (TEMs) was not significantly elevated. This study was designed to evaluate changes in frequency and function of intermediate monocytes and TEMs during chemotherapy and anti-angiogenic cancer treatment and their relation to treatment response. Monocyte populations were determined by flow cytometry in 60 metastasized CRC (mCRC) patients who received neoadjuvant chemotherapy with or without bevacizumab. Blood samples were taken before treatment, after two therapy cycles, at the end of neoadjuvant therapy and immediately before surgical resection of liver metastases. Neoadjuvant treatment resulted in a significant increase in circulating intermediate monocytes which was most pronounced after two cycles and positively predicted tumor response (AUC = 0.875, p = 0.005). With a cut-off value set to 1% intermediate monocytes of leukocytes, this parameter showed a predictive sensitivity and specificity of 75% and 88%. Anti-angiogenic therapy with bevacizumab had no impact on monocyte populations including TEMs. In 15 patients and six healthy controls, the gene expression profile and the migratory behavior of monocyte subsets was evaluated. The profile of intermediate monocytes suggested functions in antigen presentation, inflammatory cytokine production, chemotaxis and was remarkably stable during chemotherapy. Intermediate monocytes showed a preferential migratory response to tumor-derived signals in vitro and correlated with the level of CD14(+)/CD16(+) monocytic infiltrates in the resected tumor tissue. In conclusion, the rapid rise of intermediate monocytes during chemotherapy may offer a simple marker for response prediction and a timely change in regimen.

Monocytes with angiogenic potential are selectively induced by liver resection and accumulate near the site of liver regeneration.

BACKGROUND: Monocytes reportedly contribute to liver regeneration. Three subsets have been identified to date: classical, intermediate, non-classical monocytes. The intermediate population and a subtype expressing TIE2 (TEMs) were suggested to promote angiogenesis. In a clinical setting, we investigated which monocyte subsets are regulated after liver resection and correlate with postoperative liver function. METHODS: In 38 patients monocyte subsets were evaluated in blood and subhepatic wound fluid by flow cytometry before and 1-3 days after resection of colorectal liver metastases. The monocyte-regulating cytokines macrophage colony stimulating factor (M-CSF), transforming growth factor beta 1 (TGFß1), and angiopoietin 2 (ANG-2) were measured in patient plasma by ELISA. C-reactive protein (CRP) and liver function parameters were retrieved from routine hospital analyses. RESULTS: On post-operative day (POD) 1 blood monocytes shifted to significantly elevated levels of intermediate monocytes. In wound fluid, a delayed surge in intermediate monocytes was detected by POD 3. Furthermore, TEMs were highly enriched in wound fluid as compared to circulation. CRP and M-CSF levels were substantially increased in patient blood after surgery and correlated significantly with the frequency of intermediate monocytes. In addition, liver function parameters showed a significant association with intermediate monocyte levels on POD 3. CONCLUSIONS: The reportedly pro-angiogenic subsets of monocytes are selectively increased upon liver resection and accumulate next to the site of liver regeneration. As previously proposed by in vitro experiments, the release of CRP and M-CSF may trigger the induction of intermediate monocytes. The correlation with liver parameters points to a functional involvement of these monocyte populations in liver regeneration which warrants further investigation.

Evidence for serotonin as a relevant inducer of liver regeneration after liver resection in humans.

UNLABELLED: Liver regeneration (LR) involves a complex interplay of growth factors and antagonists. In this context, platelet-derived serotonin (5-HT) has been identified as a critical inducer of LR in mice. Clinical evidence for a role of 5-HT in LR in humans is lacking. Accordingly, serum and plasma 5-HT was monitored perioperatively in 60 patients undergoing liver resection, of which 35 served as exploration and 25 as validation sets. Intraplatelet (IP) levels of 5-HT were calculated by subtraction of plasma 5-HT from serum values. Serum markers of liver function were used to evaluate LR and liver dysfunction (LD). In the exploration setting, IP 5-HT levels significantly decreased after liver resection (P < 0.001) and gradually recovered during the first week. IP 5-HT measured before surgery specifically predicted LD in the subsequent 7 days (area under the curve: 0.721; P = 0.029). Patients suffering from postoperative LD and morbidity were found to have reduced IP 5-HT levels during the entire perioperative period. Furthermore, we validated that reduced preoperative IP 5-HT (<73 ng/mL) was associated with an increased incidence of postoperative LD and morbidity (P = 0.045 and P = 0.021) and were able to demonstrate that IP 5-HT levels were an independent predictor of poor clinical outcome. CONCLUSIONS: These findings provide evidence that IP 5-HT correlates with LR in humans: Patients with low IP 5-HT before liver resection suffered from delayed hepatic regeneration. Therefore, IP 5-HT levels may prove a helpful clinical marker to predict postoperative LD and clinical outcome before hepatic resection and initiate suitable interventions.

Overexpression of the transcriptional repressor complex BCL-6/BCoR leads to nuclear aggregates distinct from classical aggresomes.

Nuclear inclusions of aggregated proteins have primarily been characterized for molecules with aberrant poly-glutamine repeats and for mutated or structurally altered proteins. They were termed "nuclear aggresomes" and misfolding was shown to promote association with molecular chaperones and proteasomes. Here, we report that two components of a transcriptional repressor complex (BCL-6 and BCoR) of wildtype amino acid sequence can independently or jointly induce the formation of nuclear aggregates when overexpressed. The observation that the majority of cells rapidly downregulate BCL-6/BCoR levels, supports the notion that expression of these proteins is under tight control. The inclusions occur when BCL-6/BCoR expression exceeds 150-fold of endogenous levels. They preferentially develop in the nucleus by a gradual increase in aggregate size to form large, spheroid structures which are not associated with heat shock proteins or marked by ubiquitin. In contrast, we find the close association of BCL-6/BCoR inclusions with PML bodies and a reduction in aggregation upon the concomitant overexpression of histone deacetylases or heat shock protein 70. In summary, our data offer a perspective on nuclear aggregates distinct from classical "nuclear aggresomes": Large complexes of spheroid structure can evolve in the nucleus without being marked by the cellular machinery for protein refolding and degradation. However, nuclear proteostasis can be restored by balancing the levels of chaperones.

Intermediate monocytes but not TIE2-expressing monocytes are a sensitive diagnostic indicator for colorectal cancer.

We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs) in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N = 32) and in colorectal carcinoma patients with localized (N = 24) or metastatic (N = 37) disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes) the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer.

Discrimination between circulating endothelial cells and blood cell populations with overlapping phenotype reveals distinct regulation and predictive potential in cancer therapy.

BACKGROUND: Circulating endothelial cells (CECs) have been proposed to predict patient response to antiangiogenic cancer therapy. However, contradictory reports and inconsistency in the phenotypic identification of CECs have led us to compare three cell populations with partially overlapping phenotype in cancer patients receiving chemotherapy and the antiangiogenic agent bevacizumab. METHODS: Patients (n = 20) with locally advanced pancreatic cancer were monitored during 16 weeks of neoadjuvant treatment with gemcitabine and bevacizumab. Detection of circulating cell populations was based on the marker combination CD45, CD31, and CD146; levels of viable and dead (7-aminoactinomycin D-positive) cells were evaluated by flow cytometry in 2-week intervals. RESULTS: We were able to discriminate and concomitantly monitor three cell populations elevated in cancer patients. Whereas CECs were defined as CD45(-) CD31(+) CD146(+), the distinct populations of CD45(-) CD31(-) CD146(+) and CD45(-) CD31(high) CD146(-) cells were partly positive for CD3 and CD41, respectively. CECs and CD45(-) CD31(-) CD146(+) cells increased during therapy; the rise in dead cells was positively correlated with patient response or survival. Conversely, CD45(-) CD31(high) CD146(-) cells decreased in neoadjuvant treatment. A highly significant correlation was established for improved patient response and a minor decrease in viable cell counts. CONCLUSIONS: Flow cytometric CEC analysis based on CD45, CD31, and CD146 requires careful discrimination between blood cell populations with overlapping phenotype showing hallmarks of activated T cells and large platelets. However, these three cell populations show distinct regulation during cancer therapy, and their concomitant analysis may offer extended prognostic and predictive information.

Platelet-stored angiogenesis factors: clinical monitoring is prone to artifacts.

BACKGROUND: The analysis of angiogenesis factors in the blood of tumor patients has given diverse results on their prognostic or predictive value. Since mediators of angiogenesis are stored in platelets, their measurement in plasma is sensitive to inadvertent platelet activation during blood processing. METHODS: Variants of blood withdrawal and plasma preparation were evaluated by ELISA for the detection of TSP-1, PF-4, VEGF and PD-ECGF. A total of 22 pancreatic cancer patients and 29 healthy volunteers were evaluated. RESULTS: Plasma preparation with the anticoagulant mix of citrate, theophylline, adenosine, dipyridamole (CTAD) and immediate blood processing at 4°C was required for reproducible measurements of TSP-1, PF-4 and VEGF. Blood collection by venflon or inadvertent hemolysis during blood withdrawal caused significantly elevated TSP-1 and PF-4 values. When optimized plasma preparation was applied, a significant increase of TSP-1 and VEGF in cancer patients was detected (P=0.006; P< 0.001). CONCLUSION: The reliable plasma analysis of circulating platelet-stored angiogenesis factors requires preparation with CTAD at 4°C and blood collection by butterfly needle. Suboptimal procedures of plasma preparation are commonly applied in clinical monitoring of angiogenesis parameters which may account for the differences in reported plasma values and may have masked their predictive or prognostic marker potential.

Myelosuppression of thrombocytes and monocytes is associated with a lack of synergy between chemotherapy and anti-VEGF treatment.

PURPOSE: Chemotherapeutic agents that have shown improved patient outcome when combined with anti-vascular endothelial growth factor (VEGF) therapy were recently identified to induce the mobilization of proangiogenic Tie-2-expressing monocytes (TEMs) and endothelial progenitor cells (EPCs) by platelet release of stromal cell-derived factor 1α (SDF-1α). VEGF blockade was found to counteract cell mobilization. We aimed to determine why agents like gemcitabine do not elicit TEM and EPC recruitment and may therefore lack synergy with anti-VEGF therapy. EXPERIMENTAL DESIGN: Locally advanced pancreatic cancer patients (n = 20) were monitored during 16 weeks of neoadjuvant therapy. Treatment was based on gemcitabine with or without the addition of bevacizumab. Blood levels of proangiogenic cell populations and angiogenesis factors were determined in 2-week intervals. RESULTS: The lack of EPC mobilization during gemcitabine therapy was associated with severe thrombocytopenia and reduced SDF-1α blood concentrations. Furthermore, myelosuppression by gemcitabine correlated significantly with loss of TEMs. With respect to angiogenic factors stored and released by platelets, plasma levels of the angiogenesis inhibitor thrombospondin 1 (TSP-1) were selectively decreased and correlated significantly with thrombocytopenia in response to gemcitabine therapy. CONCLUSIONS: A thorough literature screen identified thrombocytopenia as a common feature of chemotherapeutic agents that lack synergy with anti-VEGF treatment. Our results on gemcitabine therapy indicate that myelosuppression (in particular, with respect to thrombocytes and monocytes) interferes with the mobilization of proangiogenic cell types targeted by bevacizumab and may further counteract antiangiogenic therapy by substantially reducing the angiogenesis inhibitor TSP-1.