Microbiome Dysbiosis with Enterococcus Presence in the Upper Gastrointestinal Tract is A Risk Factor for Mortality in Patients Undergoing Surgery for Pancreatic Cancer.

BACKGROUND: Recent retrospective studies suggest a role for distinct microbiota in the perioperative morbidity and mortality of pancreatic head resections. OBJECTIVE: We aimed to prospectively investigate the microbial colonization of critical operative sites of pancreatic head resections to identify microbial stratification factors for surgical and long-term oncologic outcomes. METHODS: Prospective biomarker study applying 16S rRNA sequencing and microbial culturing to samples collected from various sites of the GI tract and surgical sites of patients during pancreatic head resections at a German single high-volume pancreatic center. RESULTS: A total of 101 patients were included (38 non-cancer, 63 cancer patients [50 PDAC patients]) in the study. In a first data analysis series, 16S rRNA sequencing data were utilized from 96 patients to assess associations of microbiome profiles with clinical parameters and outcomes. In general, microbiome composition varied according to sampling site, cancer, age or preoperative ERCP intervention, notably for the bile microbiome. In the PDAC subcohort, compositional variance of the bile or periampullary microbiome was significantly associated with postoperative complications such as ICU admission; on a taxonomic level we observed Enterococcus spp. to be significantly more abundant in patients developing deep or organ-space surgical site infections (SSI). Elevated Enterococcus relative abundances in the upper GI tract, in turn, were associated with 6-months mortality rates. In a second step, we focused on microbiological cultures collected from bile aspirates during surgery and investigated associations with perioperative complications and long-term survival. Notably, Enterococcus spp. were among the most prevalent pathobiont isolates observed in cancer patient bile specimens that were associated with severe SSIs, and thereby elevated mortality rates up to 24 months. Clinically relevant postoperative pancreatic fistulas or severe SSI were found as other major variables determining short-term mortality in this cancer patient cohort. In the context of adverse microbiological factors, a preoperative ERCP was also observed to segregate long-term survival, and it appeared to interact with the presence of Enterococcus spp. as highest mortality rates were observed in PDAC patients with both preoperative ERCP and presence of E. faecalis in bile aspirates. CONCLUSIONS: The presence of Enterococcus spp. in bile ducts of PDAC patients undergoing pancreatic surgery represents a significant risk factor for perioperative infections and, thereby, elevated postoperative and long-term mortality. This finding supports previous data on the use of the antibiotic drug piperacillin-tazobactam as appropriate perioperative antibiotic prophylaxis for preventing adverse outcomes after pancreatoduodenectomy.

Tigecycline causes loss of cell viability mediated by mitochondrial OXPHOS and RAC1 in hepatocellular carcinoma cells.

BACKGROUND: Despite recent advances in locoregional, systemic, and novel checkpoint inhibitor treatment, hepatocellular carcinoma (HCC) is still associated with poor prognosis. The feasibility of potentially curative liver resection (LR) and transplantation (LT) is limited by the underlying liver disease and a shortage of organ donors. Especially after LR, high recurrence rates present a problem and circulating tumor cells are a major cause of extrahepatic recurrence. Tigecycline, a commonly used glycylcycline antibiotic, has been shown to have antitumorigenic effects and could be used as a perioperative and adjuvant therapeutic strategy to target circulating tumor cells. We aimed to investigate the effect of tigecycline on HCC cell lines and its mechanisms of action. METHODS: Huh7, HepG2, Hep3B, and immortalized hepatocytes underwent incubation with clinically relevant tigecycline concentrations, and the influence on proliferation, migration, and invasion was assessed in two- and three-dimensional in vitro assays, respectively. Bioinformatic analysis was used to identify specific targets of tigecycline. The expression of RAC1 was detected using western blot, RT-PCR and RNA sequencing. ELISA and flow cytometry were utilized to measure reactive oxygen species (ROS) generation upon tigecycline treatment and flow cytometry to detect alterations in cell cycle. Changes in mitochondrial function were detected via seahorse analysis. RNA sequencing was performed to examine involved pathways. RESULTS: Tigecycline treatment resulted in a significant reduction of mitochondrial function with concomitantly preserved mitochondrial size, which preceded the observed decrease in HCC cell viability. The sensitivity of HCC cells to tigecycline treatment was higher than that of immortalized non-cancerous THLE-2 hepatocytes. Tigecycline inhibited both migratory and invasive properties. Tigecycline application led to an increase of detected ROS and an S-phase cell cycle arrest. Bioinformatic analysis identified RAC1 as a likely target for tigecycline and the expression of this molecule was increased in HCC cells as a result of tigecycline treatment. CONCLUSION: Our study provides evidence for the antiproliferative effect of tigecycline in HCC. We show for the first time that this effect, likely to be mediated by reduced mitochondrial function, is associated with increased expression of RAC1. The reported effects of tigecycline with clinically relevant and achievable doses on HCC cells lay the groundwork for a conceivable use of this agent in cancer treatment.

Low expression of galectin-3 is associated with poor survival in node-positive breast cancers and mesenchymal phenotype in breast cancer stem cells.

BACKGROUND: Galectin-3 (Gal3) plays diverse roles in cancer initiation, progression, and drug resistance depending on tumor type characteristics that are also associated with cancer stem cells (CSCs). Recurrence of breast carcinomas may be attributed to the presence of breast CSCs (BCSCs). BCSCs exist in mesenchymal-like or epithelial-like states and the transition between these states endows BCSCs with the capacity for tumor progression. The discovery of a feedback loop with galectins during epithelial-to-mesenchymal transition (EMT) prompted us to investigate its role in breast cancer stemness. METHOD: To elucidate the role of Gal3 in BCSCs, we performed various in vitro and in vivo studies such as sphere-formation assays, Western blotting, flow cytometric apoptosis assays, and limited dilution xenotransplant models. Histological staining for Gal3 in tissue microarrays of breast cancer patients was performed to analyze the relationship of clinical outcome and Gal3 expression. RESULTS: Here, we show in a cohort of 87 node-positive breast cancer patients treated with doxorubicin-based chemotherapy that low Gal3 was associated with increased lymphovascular invasion and reduced overall survival. Analysis of in vitro BCSC models demonstrated that Gal3 knockdown by small hairpin RNA (shRNA) interference in epithelial-like mammary spheres leads to EMT, increased sphere-formation ability, drug-resistance, and heightened aldefluor activity. Furthermore, Gal3negative BCSCs were associated with enhanced tumorigenicity in orthotopic mouse models. CONCLUSIONS: Thus, in at least some breast cancers, loss of Gal3 might be associated with EMT and cancer stemness-associated traits, predicts poor response to chemotherapy, and poor prognosis.

Two sides of the same coin: stem cells in cancer and regenerative medicine.

Multipotent stromal cells (MSCs) derived from bone marrow, adipose tissue, cord blood, and other origins have recently received much attention as potential therapeutic agents with beneficial immunomodulatory and regenerative properties. In their native tissue environment, however, such cells also appear to have essential functions in building and supporting tumor microenvironments, providing metastatic niches, and maintaining cancer hallmarks. Here, we consider the varied roles of these tissue-resident stroma-associated cells, synthesize recent and emerging discoveries, and discuss the role, potential, and clinical applications of MSCs in cancer and regenerative medicine.-Ilmer, M., Vykoukal, J., Recio Boiles, A., Coleman, M., Alt, E. Two sides of the same coin: stem cells in cancer and regenerative medicine.

Hepatoblastoma cells express truncated neurokinin-1 receptor and can be growth inhibited by aprepitant in vitro and in vivo.

BACKGROUND & AIMS: Multidrug resistance presents a major problem in hepatoblastoma (HB), and new anti-tumor strategies are desperately needed. The substance P (SP)/neurokinin-1 receptor (NK1R) complex has been discovered to be pivotal in the development of a variety of human cancers, and NK1R antagonists, such as the clinical drug aprepitant, are promising future anticancer agents. Yet, the role of the SP/NK1R complex as a potential anticancer target in HB is unknown. METHODS: Human HB cell lines HepT1, HepG2, and HuH6, human tumor samples from 17 children with HB as well as mice xenografted with human HB cell line HuH6 were analyzed regarding the SP/NK1R complex as a potential new anti-tumor target in HB. RESULTS: Therapeutic targeting with the NK1R antagonists aprepitant, L-733,060, and L-732,138 led to growth inhibition and apoptosis in HepT1, HepG2, and HuH6 cells in a dose-dependent manner. Intriguingly, HB cells predominantly expressed the truncated splice variant of NK1R. Human fibroblasts showed only dismal NK1R expression and were significantly more resistant. Stimulation of HB cells with SP, NK1R's natural ligand, caused increased growth rates and abrogated the anti-proliferative effect of NK1R antagonists. Expression analysis of 17 human HB samples confirmed the clinical relevance of NK1R. Most importantly, oral treatment of a HuH6 xenograft mouse model with 80mg/kg/day aprepitant for 24days resulted in a striking reduction of tumor growth, as evidenced by reduced tumor volume and weight, lowered tumor-specific alpha-fetoprotein (AFP) serum levels, and decreased number of Ki-67 positive cells. Furthermore, aprepitant treatment inhibited in vivo angiogenesis. CONCLUSIONS: For the first time, we describe the NK1R in its truncated splice variant as a potent target in human HB and an inhibitory effect in vivo and in vitro by NK1R antagonists. Therefore, NK1R antagonists should be considered promising new candidates for innovative therapeutic strategies against HB.

Hepatocellular Carcinoma: The Role of Surgery in Liver Cirrhosis.

Background: Liver surgery is an essential component of hepatocellular carcinoma (HCC) treatment. Advances in surgical techniques and perioperative care have improved outcomes and have helped to expand surgical indications. However, liver fibrosis and cirrhosis still remain major problems for liver surgery due to the relevant impact on liver regeneration of the future liver remnant (FLR) after surgery. Especially in patients with clinically significant portal hypertension due to liver cirrhosis, surgery is limited. Despite recent efforts in developing predictive models, estimating the postoperative hepatic function remains difficult. Summary: In this review, we focus on the role of surgery in the treatment of HCC in structurally altered livers. The importance of assessing FLR with techniques such as contrast-enhanced CT, e.g., with the help of artificial intelligence is highlighted. Moreover, strategies for increasing the FLR with approaches like portal vein embolization and liver vein deprivation prior to surgery are discussed. Patient selection, minimally invasive liver surgery including robotic techniques, and perioperative concepts like the Enhanced Recovery After Surgery (ERAS) guidelines are identified as crucial parts of avoiding posthepatectomy liver failure. Key Message: The need for ongoing research to optimize patient selection criteria and perioperative care and to develop innovative biomarkers for outcome prediction is emphasized.

Preoperative ultrasound elastography for postoperative pancreatic fistula prediction after pancreatoduodenectomy: A prospective study.

BACKGROUND: Postoperative pancreatic fistulas are the most frequent major complications after pancreatoduodenectomy. The soft pancreatic texture is a critical, independent risk factor for postoperative pancreatic fistulas after pancreatoduodenectomy. The current gold standard for postoperative pancreatic fistula risk evaluation consists of the surgeon's intraoperative palpation of the pancreatic texture and, thus, lacks objectivity. In this prospective study, we used ultrasound-based shear-wave elastography, image data analysis, and a fistula risk score calculator to correlate the stiffness of pancreatic tissue with the occurrence of clinically relevant postoperative pancreatic fistulas. METHODS: We included 100 patients with pancreatic pathologies (71% pancreatic ductal adenocarcinoma) and 100 healthy individuals who were preoperatively assessed via real-time tissue ultrasound-based shear-wave elastography on a Philips EPIQ 7 ultrasound device and had pancreatic parenchyma histologically evaluated with manually stained images. RESULTS: We found a significant difference in the mean elasticity between the soft (1.22 m/s) and the hard pancreas group (2.10 m/s; P < .0001). The mean elasticity significantly correlated with the pancreatic fibrosis rate and the appearance of a postoperative pancreatic fistula after pancreatoduodenectomy. Low elasticity (≤1.2 m/s, mean) correlated with soft and high elasticity (>2.0 m/s, mean) with hard pancreatic parenchyma, as assessed by pathologic evaluation. Multivariate analysis revealed a mean elasticity of <1.3 m/s as a significant cut-off predictor for clinically relevant postoperative pancreatic fistulas (P = .003; Youden-Index = 0.6945). CONCLUSION: Preoperative ultrasound-based shear-wave elastography is a feasible and objective clinical diagnostic modality in evaluating pancreatic tissue stiffness. A mean pancreatic elasticity of <1.3 m/s was a significant independent risk predictor of clinically relevant postoperative pancreatic fistulas after pancreatoduodenectomy.

Effect of Surgery on Postoperative Levels of the Gut Homeostasis-Regulating Enzyme Intestinal Alkaline Phosphatase.

BACKGROUND: Intestinal homeostasis is a crucial factor for complication-free short- and long-term postoperative recovery. The brush border enzyme intestinal alkaline phosphatase (IAP) is an important regulator of gut barrier function and intestinal homeostasis and prevents endotoxemia by detoxifying lipopolysaccharides (LPSs). As IAP is predominantly secreted by enterocytes in the duodenum, we hypothesized that pancreaticoduodenectomy (PD) leads to a significantly stronger decrease in IAP than other major abdominal surgery. STUDY DESIGN: Pre- and postoperative blood, stool, and intestinal samples were collected from patients undergoing PD, as well as other major surgical procedures without duodenectomy. The samples were analyzed using enzyme histochemistry, the para -nitrophenyl phosphate method for IAP, and the limulus amebocyte lysate assay for LPS. RESULTS: Overall, 88 patients were prospectively enrolled in the study. Fecal IAP activity negatively correlated with serum LPS (r = -0.3603, p = 0.0006). PD led to a significant decline in IAP compared to preoperative baseline levels (p < 0.0001). The decline in IAP correlated with the length of proximal small intestinal resection (r = 0.4271, p = 0.0034). Compared to controls, PD was associated with a much more pronounced reduction in IAP-also after adjusting for surgical trauma (operative time, blood loss; r = 0.4598, p = 0.0086). Simultaneously, PD triggered a clearly more prominent increase in serum LPS compared to controls (p = 0.0001). Increased postoperative LPS was associated with an elongated hospitalization (r = 0.7534, p = 0.0062) and more prominent in pancreatic cancer (p = 0.0009). CONCLUSIONS: Based upon the functional roles for IAP, supplementation with exogenous IAP might be a new treatment option to improve short- and long-term outcome after PD.

Baseline Interleukin-6 as a Preoperative Biomarker for Liver Fibrosis.

Introduction: Liver (hepatic) fibrosis (LF) is characterized by impaired function and regenerative capacity of the liver and can lead to significantly increased morbidity and mortality in the context of surgical liver resection (LR). For this reason, it is crucial to identify the extent of LF preoperatively. Interleukin-6 (IL-6) is known to play a key role in the pathogenesis of LF, but its exact value as a preoperative marker is unknown. This study aimed to investigate the correlation between preoperatively determined IL-6 and the presence of LF. Methods: In this prospective study, IL-6 was determined in 134 consecutive patients undergoing LR. Patients with liver cirrhosis (LC) and patients with clinical or laboratory signs of inflammation were excluded. LF was graded by a blinded pathologist with regard to the degree of LF according to the Desmet classification (0-4). Baseline IL-6 and degree of LF were correlated. Results: A total of 134 patients were prospectively included prior to LR. For 104 patients, LF was graded and inflammatory parameters were available. Thirty-five of these patients showed LC (Desmet 4), and another 33 patients showed preoperatively elevated inflammatory markers. Two of the remaining patients were liver transplant patients. These patients were excluded from the final analysis. According to Desmet, the remaining 34 patients had LF grade 0 or 1 (none or minimal LF) in 26 cases and LF grade 2 or 3 (moderate-to-severe LF) in 8 cases. Correlation of LF with preoperatively determined IL-6 yielded significantly higher IL-6 levels in the group of patients with moderate-to-severe LF (Desmet 2 or 3) compared to the group with none or minimal LF (Desmet 0 or 1; p = 0.0495). Conclusion: In the context of LR, our results showed a correlation of preoperatively determined IL-6 with the extent of LF present. Higher serum baseline IL-6 concentrations were associated with a higher degree of LF, whereas no other blood parameter or score was that predictive for LF. Our results suggest that baseline IL-6 might serve as a valuable parameter to assess LF prior to LR. More patients need to be analyzed to further evaluate and confirm the predictive accuracy of IL-6 for LF.

Opposing effects of cannabidiol in patient-derived neuroendocrine tumor, pheochromocytoma/paraganglioma primary cultures.

CONTEXT: Treatment options for advanced neuroendocrine tumors (NETs), pheochromocytomas and paragangliomas (together PPGLs) are still limited. In recent years, anti-tumor effects of cannabinoids have been reported; however, there are only very limited data available in NETs or PPGLs. OBJECTIVE: Investigation of the effects of cannabidiol (CBD) on patient-derived human NET/PPGL primary cultures and on NET/PPGL cell lines. METHODS: We established primary cultures derived from 46 different patients with PPGLs (n = 35) or NETs (n = 11) who underwent tumor resection at two centers. Treatment of patient primary cultures with clinically relevant doses (5 µM) and slightly higher doses (10 µM) of CBD was performed. RESULTS: We found opposing effects of 5 µM CBD: significant anti-tumor effects in 5/35 (14%) and significant tumor-promoting effects in 6/35 (17%) of PPGL primary cultures. In terms of anti-tumor effects, cluster 2-related PPGLs showed significantly stronger responsivity to CBD compared to cluster 1-related PPGLs (p = 0.042). Of the cluster 2-related tumors, NF1 PPGLs showed strongest responsivity (4/5 PPGL primary cultures with a significant decrease in cell viability were NF1-mutated). We also found opposing effects of 10 µM CBD in PPGLs and NETs: significant anti-tumor effects in 9/33 of PPGL (27%) and 3/11 of NET (27%) primary cultures, significant tumor-promoting effects in 6/33 of PPGL (18%) and 2/11 of NET (18%) primary cultures. CONCLUSIONS: We suggest a potential novel treatment option for some NETs/PPGLs, but also provide evidence for caution when applying cannabinoids as supportive therapy for pain or appetite management to cancer patients, and possibly as health supplements.

Detection of breast cancer cells in blood samples by immunostaining of the Thomsen-Friedenreich antigen.

AIM: Disseminated tumor cells are found in the bone marrow of patients with epithelial carcinoma and are correlated with a poor prognosis of the disease. Their detection is a technical challenge. This report describes a model system for the detection of cancer cells by co-immunostaining of Thomsen-Friedenreich and Her-2 antigens. METHODS & RESULTS: Small numbers of cancer cells from different cancer cell lines were mixed with blood samples of healthy donors. Cytospins were prepared and double immunostaining against Thomsen-Friedenreich antigen and Her-2 was carried out by fluorochrome-coupled antibodies. Quantification of Thomsen-Friedenreich and/or Her-2-positive cells was performed with an epifluorescence microscope. On average, 83% of cancer cells were recovered by this method. CONCLUSION: Immunostaining is a useful method for the detection of cancer cells in blood samples. Results of this model system will be transferred to bone marrow patient samples to prove the benefits for detection of disseminated tumor cells.

Detection of tumor cell-specific mRNA in the peripheral blood of patients with breast cancer­evaluation of several markers with real-time reverse transcription-PCR.

It is widely known that cells from epithelial tumors, e.g., breast cancer, detach from their primary tissue and enter blood circulation. We show that the presence of circulating tumor cells (CTCs) in samples of patients with primary and metastatic breast cancer can be detected with an array of selected tumor-marker-genes by reverse transcription real-time PCR. The focus of the presented work is on detecting differences in gene expression between healthy individuals and adjuvant and metastatic breast cancer patients, not an accurate quantification of these differences. Therefore, total RNA was isolated from blood samples of healthy donors and patients with primary or metastatic breast cancer after enrichment of mononuclear cells by density gradient centrifugation. After reverse transcription real-time PCR was carried out with a set of marker genes (BCSP, CK8, Her2, MGL, CK18, CK19). B2M and GAPDH were used as reference genes. Blood samples from patients with metastatic disease revealed increased cytokine gene levels in comparison to normal blood samples. Detection of a single gene was not sufficient to detect CTCs by reverse transcription real-time PCR. Markers used here were selected based on a recent study detecting cancer cells on different protein levels. The combination of such a marker array leads to higher and more specific discovery rates, predominantly in metastatic patients. Identification of CTCs by PCR methods may lead to better diagnosis and prognosis and could help to choose an adequate therapy.

ROS Generative Black Phosphorus-Tamoxifen Nanosheets for Targeted Endocrine-Sonodynamic Synergistic Breast Cancer Therapy.

Introduction: Tamoxifen (TAM) has proven to be a therapeutic breakthrough to reduce mortality and recurrence in estrogen receptor-positive (ER+) breast cancer patients. However, the application of TAM exhibits low bioavailability, off-target toxicity, instinct and acquired TAM resistance. Methods: We utilized black phosphorus (BP) as a drug carrier and sonosensitizer, integrated with TAM and tumor-targeting ligand folic acid (FA) to construct TAM@BP-FA for synergistic endocrine and sonodynamic therapy (SDT) of breast cancer. The exfoliated BP nanosheets were modified through in situ polymerization of dopamine, followed by electrostatic adsorption of TAM and FA. The anticancer effect of TAM@BP-FA was evaluated through in vitro cytotoxicity and in vivo antitumor model. RNA-sequencing (RNA-seq), quantitative real-time PCR, Western blot analysis, flow cytometry analysis and peripheral blood mononuclear cells (PBMCs) analysis were performed for mechanism investigation. Results: TAM@BP-FA had satisfactory drug loading capacity, the TAM release behavior can be controlled through pH microenvironment and ultrasonic stimulation. An amount of hydroxyl radical (∙OH) and singlet oxygen (1O2) were as expected generated under ultrasound stimulation. TAM@BP-FA nanoplatform showed excellent internalization in both TAM-sensitive MCF7 and TAM-resistant (TMR) cells. Using TMR cells, TAM@BP-FA displayed significantly enhanced antitumor ability in comparison with TAM (7.7% vs 69.6% viability at 5µg/mL), the additional SDT further caused 15% more cell death. RNA-seq unraveled the TAM@BP-FA antitumor mechanisms including effects on cell cycle, apoptosis and cell proliferation. Further analysis showed additional SDT successfully triggering reactive oxygen species (ROS) generation and mitochondrial membrane potential (MMP) reduction. Moreover, PBMCs exposed to TAM@BP-FA induced an antitumor immune response by natural killer (NK) cell upregulation and immunosuppression macrophage reduction. Conclusion: The novel BP-based strategy not only delivers TAM specifically to tumor cells but also exhibits satisfactory antitumor effects through targeted therapy, SDT, and immune cell modulation. The nanoplatform may provide a superior synergistic strategy for breast cancer therapy.

WNT enhancing signals in pancreatic cancer are transmitted by LGR6.

The G-protein-coupled receptor LGR6 associates with ligands of the R-Spondin (RSPO) family to potentiate preexisting signals of the canonical WNT pathway. However, its importance in pancreatic ductal adenocarcinoma (PDAC) remains unclear. Here, we show that LGR6 is differentially expressed in various PDAC cell lines of mesenchymal and epithelial phenotype, respectively, siding with the latter subsets. LGR6 expression is altered based upon the cells' WNT activation status. Furthermore, extrinsic enhancement of WNT pathway signaling increased LGR6 expression suggestive of a reinforcing self-regulatory loop in highly WNT susceptible cells. Downregulation of LGR6 on the other hand, seemed to tamper those effects. Last, downregulation of LGR6 reduced cancer stemness as determined by functional in vitro assays. These findings shed new insights into regulatory mechanisms for the canonical WNT pathway in pancreatic cancer cells. It may also have potential value for treatment stratification of PDAC.

Liver Transplant Oncology: Towards Dynamic Tumor-Biology-Oriented Patient Selection.

While liver transplantation was initially considered as a curative treatment modality only for hepatocellular carcinoma, the indication has been increasingly extended to other tumor entities over recent years, most recently to the treatment of non-resectable colorectal liver metastases. Although oncologic outcomes after liver transplantation (LT) are consistently good, organ shortage forces stringent selection of suitable candidates. Dynamic criteria based on tumor biology fulfill the prerequisite of an individual oncological prediction better than traditional morphometric criteria based on tumor burden. The availability of specific (neo-)adjuvant therapies and customized modern immunosuppression may further contribute to favorable post-transplantation outcomes on the one hand and simultaneously open the path to LT as a curative option for advanced stages of tumor patients. Herein, we provide an overview of the oncological LT indications, the selection process, and expected oncological outcome after LT.

Myeloid-Derived Suppressor Cells in Solid Tumors.

Myeloid-derived suppressor cells (MDSCs) are one of the main suppressive cell population of the immune system. They play a pivotal role in the establishment of the tumor microenvironment (TME). In the context of cancers or other pathological conditions, MDSCs can differentiate, expand, and migrate in large quantities during circulation, inhibiting the cytotoxic functions of T cells and NK cells. This process is regulated by ROS, iNOS/NO, arginase-1, and multiple soluble cytokines. The definition of MDSCs and their phenotypes in humans are not as well represented as in other organisms such as mice, owing to the absence of the cognate molecule. However, a comprehensive understanding of the differences between different species and subsets will be beneficial for clarifying the immunosuppressive properties and potential clinical values of these cells during tumor progression. Recently, experimental evidence and clinical investigations have demonstrated that MDSCs have a close relationship with poor prognosis and drug resistance, which is considered to be a leading marker for practical applications and therapeutic methods. In this review, we summarize the remarkable position of MDSCs in solid tumors, explain their classifications in different models, and introduce new treatment approaches to target MDSCs to better understand the advancement of new approaches to cancer treatment.

PBXIP1 - An indicator for poor outcome and metastatic spread in colorectal cancer.

Tumor cell heterogeneity in colorectal cancers within the same genetic background is a well-described phenomenon. In this work, we investigate the role of hematopoietic pre-B-cell leukemia transcription factor (PBX)-interacting protein (HPIP/PBXIP1) in tumor cell subpopulations with differential Wingless-related integration site (WNT) activity as well as its potential associations with epithelial-mesenchymal transition (EMT) and clinical associations in colorectal cancer. We used in situ analyses to identify immunohistochemical expression of PBXIP1 in normal and colorectal cancer tissues and biostatistical approaches to determine its function and regulatory correlations. Clinical associations were analyzed in a case control collection of metastatic and non-metastatic colon cancers and gene expression data sets of colorectal cancers with recorded clinical follow-up data. PBXIP1 was expressed in single epithelial cells from tumor-free colon crypts as well as in tumor cells with high WNT activity. Colorectal cancer cells close to the invasive edge seemed to possess higher PBXIP1 levels indicative of associations with EMT, whereas stromal cells in the tumor microenvironment appeared mostly negative. PBXIP1 expression was associated with local metastasis to lymph nodes as well as distant metastasis to secondary organs in a case-control collection consisting of 91 cases with or without distant metastasis. Furthermore, high expression of PBXIP1 in The Cancer Genome Atlas (TCGA) data set was associated with worse overall survival in colon cancer. PBXIP1 might serve as a novel histological prognostic and regulatory indicator for EMT processes in colorectal cancer that seems to correlate with cancer cell subtypes of high baseline WNT activity.

Effect of Sirolimus vs. Everolimus on CMV-Infections after Kidney Transplantation-A Network Meta-Analysis.

(1) Background: Following renal transplantation, infection with cytomegalovirus (CMV) is a common and feared complication. mTOR-inhibitor (mTOR-I) treatment, either alone or in combination with calcineurininhibitors (CNIs), significantly reduces the CMV incidence after organ transplantation. As of now, there is no information on which mTOR-I, sirolimus (SIR) or everolimus (ERL), has a stronger anti-CMV effect. (2) Methods: The current literature was searched for prospective randomized controlled trials in renal transplantation. There were 1164 trials screened, of which 27 could be included (11,655 pts.). We performed a network meta-analysis to analyze the relative risk of different types of mTOR-I treatment on CMV infection 12 months after transplantation compared to CNI treatment. (3) Results: Four different types of mTOR-I treatment were analyzed in network meta-analyses­SIR mono, ERL mono, SIR with CNI, ERL with CNI. The mTOR-I treatment with the strongest anti-CMV effect compared to a regular CNI treatment was ERL in combination with a CNI (relative risk (RR) 0.27, confidence interval (CI) 0.22−0.32, p < 0.0001). The other mTOR-I therapy groups showed a slightly decreased anti-CMV efficacy (SIR monotherapy (mono): RR 0.35, CI 0.22−0.57, p < 0.001; SIR with CNI: RR 0.43, CI 0.29−0.64, p < 0.0001; ERL mono: RR 0.46, CI 0.22−0.93, p = 0.031). (4) Conclusions: The anti-CMV effect of both mTOR-Is (SRL and ERL) is highly effective, irrespective of the combination with other immunosuppressive drugs. Certain differences with respect to the potency against the CMV could be found between SRL and ERL. Data gained from this analysis seem to support that a combination of ERL and CNI has the most potent anti-CMV efficacy.

Textbook outcome in hepato-pancreato-biliary surgery: systematic review.

BACKGROUND: Textbook outcome (TO) is a multidimensional measure reflecting the ideal outcome after surgery. As a benchmarking tool, it provides an objective overview of quality of care. Uniform definitions of TO in hepato-pancreato-biliary (HPB) surgery are missing. This study aimed to provide a definition of TO in HPB surgery and identify obstacles and predictors for achieving it. METHODS: A systematic literature search was conducted using PubMed, Embase, and Cochrane Database according to PRISMA guidelines. Studies published between 1993 and 2021 were retrieved. After selection, two independent reviewers extracted descriptive statistics and derived summary estimates of the occurrence of TO criteria and obstacles for achieving TO using co-occurrence maps. RESULTS: Overall, 30 studies were included. TO rates ranged between 16-69 per cent. Commonly chosen co-occurring criteria to define TO included 'no prolonged length of stay (LOS)', 'no complications', 'no readmission', and 'no deaths'. Major obstacles for achieving TO in HPB surgery were prolonged LOS, complications, and readmission. On multivariable analysis, TO predicted better overall and disease-free survival in patients with cancer. Achievement of TO was more likely in dedicated centres and associated with procedural and structural indicators, including high case-mix index and surgical volume. CONCLUSION: TO is a useful quality measure to benchmark surgical outcome. Future definitions of TO in HPB surgery should include 'no prolonged LOS', 'no complications', 'no readmission', and 'no deaths'.

Specific intraoperative antibiotic therapy abrogates the negative effect of biliary contamination on the Comprehensive Complication Index after pancreatic head resection.

BACKGROUND: The effect of bacterobilia on morbidity after pancreatoduodenectomy remains unclear. The aim of this study was to examine the influence of positive intraoperative bile cultures and perioperative antibiotic prophylaxis on morbidity measured using the Comprehensive Complication Index, a weighted composite of postoperative complications. METHODS: Intraoperative bile cultures of 182 patients who underwent pancreatoduodenectomy were obtained. We examined the effect of intraoperative bile cultures and perioperative antibiotic prophylaxis on the Comprehensive Complication Index and the occurrence of postoperative complications. To this aim, we performed general linear models controlling for relevant demographic and perioperative factors. RESULTS: Positive (versus negative) intraoperative bile cultures were associated with a higher mean Comprehensive Complication Index (25.34 vs 16.81, P = .025). The mean Comprehensive Complication Index differed significantly between individuals with positive intraoperative bile cultures and bacterial strains not covered by perioperative antibiotic prophylaxis (26.2) versus positive intraoperative bile cultures and bacterial strains sensitive to perioperative antibiotic prophylaxis (22.7) (P = .045). Positive (versus negative) intraoperative bile cultures were associated with 4.75 times (95% confidence interval: 1.74-13.00, P = .002) greater odds of wound infections. The odds of wound infection were 1.93 times (95% confidence interval: .47-8.04) greater in those with positive intraoperative bile cultures and adequate perioperative antibiotic prophylaxis and 6.14 times (95% confidence interval: 2.17-17.35) greater in those with positive intraoperative bile cultures and inadequate perioperative antibiotic prophylaxis (versus negative intraoperative bile cultures) (P = .001). CONCLUSION: Bacterobilia is associated with a significant increase in Comprehensive Complication Index and wound infections after pancreatoduodenectomy, which may be reduced by administration of a specific perioperative antibiotic prophylaxis. Acquisition of bile cultures sampled through the external conduit of patients with preoperative biliary drainage could help in selecting a specific perioperative antibiotic prophylaxis and patients with bile duct stents might benefit from broad spectrum perioperative antibiotic prophylaxis.