Cancer immunotherapy: Macs in the middle.

Response to immune checkpoint blockade cancer immunotherapy is variable, but the mechanisms that underlie this variability remain unclear. In a recent issue of Nature Medicine, Yu et al. demonstrate that liver metastases limit immunotherapy efficacy by promoting macrophage-mediated elimination of tumor-specific CD8+ T cells. Liver-directed radiotherapy in preclinical models could partially overcome this effect.

Radiomics using computed tomography to predict CD73 expression and prognosis of colorectal cancer liver metastases.

BACKGROUND: Finding a noninvasive radiomic surrogate of tumor immune features could help identify patients more likely to respond to novel immune checkpoint inhibitors. Particularly, CD73 is an ectonucleotidase that catalyzes the breakdown of extracellular AMP into immunosuppressive adenosine, which can be blocked by therapeutic antibodies. High CD73 expression in colorectal cancer liver metastasis (CRLM) resected with curative intent is associated with early recurrence and shorter patient survival. The aim of this study was hence to evaluate whether machine learning analysis of preoperative liver CT-scan could estimate high vs low CD73 expression in CRLM and whether such radiomic score would have a prognostic significance. METHODS: We trained an Attentive Interpretable Tabular Learning (TabNet) model to predict, from preoperative CT images, stratified expression levels of CD73 (CD73High vs. CD73Low) assessed by immunofluorescence (IF) on tissue microarrays. Radiomic features were extracted from 160 segmented CRLM of 122 patients with matched IF data, preprocessed and used to train the predictive model. We applied a five-fold cross-validation and validated the performance on a hold-out test set. RESULTS: TabNet provided areas under the receiver operating characteristic curve of 0.95 (95% CI 0.87 to 1.0) and 0.79 (0.65 to 0.92) on the training and hold-out test sets respectively, and outperformed other machine learning models. The TabNet-derived score, termed rad-CD73, was positively correlated with CD73 histological expression in matched CRLM (Spearman's ρ = 0.6004; P < 0.0001). The median time to recurrence (TTR) and disease-specific survival (DSS) after CRLM resection in rad-CD73High vs rad-CD73Low patients was 13.0 vs 23.6 months (P = 0.0098) and 53.4 vs 126.0 months (P = 0.0222), respectively. The prognostic value of rad-CD73 was independent of the standard clinical risk score, for both TTR (HR = 2.11, 95% CI 1.30 to 3.45, P < 0.005) and DSS (HR = 1.88, 95% CI 1.11 to 3.18, P = 0.020). CONCLUSIONS: Our findings reveal promising results for non-invasive CT-scan-based prediction of CD73 expression in CRLM and warrant further validation as to whether rad-CD73 could assist oncologists as a biomarker of prognosis and response to immunotherapies targeting the adenosine pathway.

Prognostic implications of adaptive immune features in MMR-proficient colorectal liver metastases classified by histopathological growth patterns.

BACKGROUND: After resection, colorectal cancer liver metastases (CRLM) surrounded by a desmoplastic rim carry a better prognosis than the metastases replacing the adjacent liver. However, these histopathological growth patterns (HGPs) are insufficient to guide clinical decision-making. We explored whether the adaptive immune features of HGPs could refine prognostication. METHODS: From 276 metastases resected in 176 patients classified by HGPs, tissue microarrays were used to assess intratumoral T cells (CD3), antigen presentation capacity (MHC class I) and CD73 expression producing immunosuppressive adenosine. We tested correlations between these variables and patient outcomes. RESULTS: The 101 (57.4%) patients with dominant desmoplastic HGP had a median recurrence-free survival (RFS) of 17.1 months compared to 13.3 months in the 75 patients (42.6%) with dominant replacement HGP (p = 0.037). In desmoplastic CRLM, high vs. low CD73 was the only prognostically informative immune parameter and was associated with a median RFS of 12.3 months compared to 26.3, respectively (p = 0.010). Only in dominant replacement CRLM, we found a subgroup (n = 23) with high intratumoral MHC-I expression but poor CD3+ T cell infiltration, a phenotype associated with a short median RFS of 7.9 months. CONCLUSIONS: Combining the assessments of HGP and adaptive immune features in resected CRLM could help identify patients at risk of early recurrence.

Effect of intraoperative hypovolemic phlebotomy on transfusion and clinical outcomes in patients undergoing hepatectomy: a retrospective cohort study.

BACKGROUND: There is no consensus on how to best achieve a low central venous pressure during hepatectomy for the purpose of reducing blood loss and red blood cell (RBC) transfusions. We analyzed the associations between intraoperative hypovolemic phlebotomy (IOHP), transfusions, and postoperative outcomes in cancer patients undergoing hepatectomy. METHODS: Using surgical and transfusion databases of patients who underwent hepatectomy for cancer at one institution (11 January 2011 to 22 June 2017), we retrospectively analyzed associations between IOHP and RBC transfusion on the day of surgery (primary outcome), and with total perioperative transfusions, intraoperative blood loss, and postoperative complications (secondary outcomes). We fitted logistic regression models by inverse probability of treatment weighting to adjust for confounders and reported adjusted odds ratio (aOR). RESULTS: There were 522 instances of IOHP performed during 683 hepatectomies, with a mean (standard deviation) volume of 396 (119) mL. The IOHP patients had a 6.9% transfusion risk on the day of surgery compared with 12.4% in non-IOHP patients (aOR, 0.53; 95% confidence interval [CI], 0.29 to 0.98; P = 0.04). Total perioperative RBC transfusion tended to be lower in IOHP patients compared with non-IOHP patients (14.9% vs 22.4%, respectively; aOR, 0.72; 95% CI, 0.44 to 1.16; P = 0.18). In patients with a predicted risk of ≥ 47.5% perioperative RBC transfusion, 24.6% were transfused when IOHP was used compared with 56.5% without IOHP. The incidence of severe postoperative complications (Clavien-Dindo scores ≥ 3) was similar in patients whether or not IOHP was performed (15% vs 16% respectively; aOR, 0.97; 95% CI, 0.53 to 1.54; P = 0.71). CONCLUSIONS: The use of IOHP during hepatectomy was associated with less RBCs transfused on the same day of surgery. Trials comparing IOHP with other techniques to reduce blood loss and transfusion are needed in liver surgery.

RéSUMé: CONTEXTE: Il n'existe pas de consensus quant à la meilleure façon d'obtenir une pression veineuse centrale basse pendant une hépatectomie dans le but de réduire les pertes et les transfusions sanguines. Nous avons analysé les associations entre la phlébotomie hypovolémique peropératoire, les transfusions, et les résultats cliniques postopératoires chez les patients qui subissent une hépatectomie pour cancer. MéTHODE: À l'aide de bases de données chirurgicales et transfusionnelles de patients ayant subi une hépatectomie pour cancer dans un seul établissement (du 11 janvier 2011 au 22 juin 2017), nous avons rétrospectivement analysé les associations entre la phlébotomie hypovolémique peropératoire et les transfusions érythrocytaires le jour de la chirurgie (critère d'évaluation principal) et avec les transfusions périopératoires totales, les pertes sanguines peropératoires, et les complications postopératoires (critères d'évaluation secondaires). Nous avons utilisé des modèles de régression logistique avec pondération de probabilité inverse de traitement afin de tenir compte des facteurs de confusion et rapporté les rapports de cotes ajustés (RCa). RéSULTATS: Il y a eu 522 phlébotomies hypovolémiques peropératoires exécutées au cours de 683 hépatectomies, avec un volume moyen (écart type) de 396 (119) mL. Les patients ayant eu une phlébotomie hypovolémique peropératoire avaient un risque transfusionnel de 6,9 % le jour de la chirurgie, comparativement à 12,4 % pour les patients sans phlébotomie (RCa, 0,53; intervalle de confiance [IC] de 95 %, 0,29 à 0,98; P = 0,04). Les transfusions périopératoires totales d'érythrocytes tendaient à être moins fréquentes chez les patients ayant subi une phlébotomie hypovolémique peropératoire par rapport aux patients sans phlébotomie (14,9 % vs 22,4 %, respectivement; RCa, 0,72; IC 95 %, 0,44 à 1,16; P = 0,18). Pour les patients présentant un risque prédit de transfusion périopératoire d'érythrocytes ≥ à 47,5 %, 24,6 % de ceux qui ont eu une phlébotomie hypovolémique peropératoire ont été transfusés, comparativement à 56,5 % sans phlébotomie. L'incidence des complications postopératoires graves (scores de Clavien-Dindo ≥ 3) était semblable chez tous les patients, avec ou sans phlébotomie hypovolémique peropératoire (15 % vs 16 % respectivement; RCa, 0,97; IC 95 %, 0,53 à 1,54; P = 0,71). CONCLUSIONS: L'utilisation de la phlébotomie hypovolémique peropératoire pendant une hépatectomie était associée à un moins grand nombre de transfusions érythrocytaires le jour de la chirurgie. Des études qui compareront la phlébotomie hypovolémique peropératoire à d'autres techniques visant à réduire les pertes et les transfusions sanguines sont nécessaires en chirurgie hépatique.

Predicting the Response to FOLFOX-Based Chemotherapy Regimen from Untreated Liver Metastases on Baseline CT: a Deep Neural Network Approach.

In developed countries, colorectal cancer is the second cause of cancer-related mortality. Chemotherapy is considered a standard treatment for colorectal liver metastases (CLM). Among patients who develop CLM, the assessment of patient response to chemotherapy is often required to determine the need for second-line chemotherapy and eligibility for surgery. However, while FOLFOX-based regimens are typically used for CLM treatment, the identification of responsive patients remains elusive. Computer-aided diagnosis systems may provide insight in the classification of liver metastases identified on diagnostic images. In this paper, we propose a fully automated framework based on deep convolutional neural networks (DCNN) which first differentiates treated and untreated lesions to identify new lesions appearing on CT scans, followed by a fully connected neural networks to predict from untreated lesions in pre-treatment computed tomography (CT) for patients with CLM undergoing chemotherapy, their response to a FOLFOX with Bevacizumab regimen as first-line of treatment. The ground truth for assessment of treatment response was histopathology-determined tumor regression grade. Our DCNN approach trained on 444 lesions from 202 patients achieved accuracies of 91% for differentiating treated and untreated lesions, and 78% for predicting the response to FOLFOX-based chemotherapy regimen. Experimental results showed that our method outperformed traditional machine learning algorithms and may allow for the early detection of non-responsive patients.

The safety and efficacy of hypovolemic phlebotomy on blood loss and transfusion in liver surgery: a systematic review and meta-analysis.

BACKGROUND: Hypovolemic phlebotomy (HP) is a novel intervention that involves intraoperative removal of whole blood (7-10 mL/kg) without volume replacement. The subsequent central venous pressure (CVP) reduction is hypothesized to decrease blood loss and the need for blood transfusion. The objective was to conduct a systematic assessment of the safety and efficacy of HP on blood loss and transfusion in the liver surgery literature. METHODS: MEDLINE, EMBASE, and Cochrane Library databases were searched. Outcomes of interest included blood loss, allogenic red blood cell transfusion, postoperative adverse events, and CVP change. A qualitative synthesis and meta-analysis were performed as appropriate. RESULTS: Four cohort studies, one case series, and three randomized controlled trials involving 2255 patients were included. Meta-analysis of studies involving liver resections for any indication (n = 6) found no difference in transfusion (OR 0.38, p = 0.12) or incidence of adverse events with HP compared to non-use. Pooling of studies involving liver resections for an underlying pathology (n = 4) revealed HP was associated with significant reduction in transfusion (OR 0.25, p = 0.03) but no differences in blood loss (-173 mL, p = 0.17). CONCLUSION: This review suggests HP is safe and associated with decreased transfusion in patients undergoing liver surgery. It supports further investigation.

LI-RADS for MR Imaging Diagnosis of Hepatocellular Carcinoma: Performance of Major and Ancillary Features.

Purpose To evaluate the performance of major features, ancillary features, and categories of Liver Imaging Reporting and Data System (LI-RADS) version 2014 at magnetic resonance (MR) imaging for the diagnosis of hepatocellular carcinoma (HCC). Materials and Methods This retrospective institutional review board-approved study included patients with liver MR imaging and at least one pathologically proved lesion. Between 2004 and 2016, 102 patients (275 observations including 113 HCCs) met inclusion criteria. Two radiologists independently assessed major and ancillary imaging features for each liver observation and assigned a LI-RADS category. Per-lesion estimates of diagnostic performance of major features, ancillary features, and LI-RADS categories were assessed by using generalized estimating equation models. Results Major features (arterial phase hyperenhancement, washout, capsule, and threshold growth) had a sensitivity of 88.5%, 60.6%, 32.9%, and 41.6%, and a specificity of 18.6%, 84.8%, 98.8%, and 83.2% for HCC, respectively. Ancillary features (mild-moderate T2 hyperintensity, restricted diffusion, mosaic architecture, intralesional fat, lesional fat sparing, blood products, and subthreshold growth) had a sensitivity of 62.2%, 54.8%, 9.9%, 30.9%, 23.1%, 2.8%, and 48.3%, and a specificity of 79.4%, 90.6%, 99.4%, 94.2%, 83.1%, 99.3%, and 91.4% for HCC, respectively. The LR-5 or LR-5 V categories had a per-lesion sensitivity of 50.8% and a specificity of 95.8% for HCC, respectively. The LR-4, LR-5, or LR-5 V categories (determined by using major features only vs combination of major and ancillary features) had a per-lesion sensitivity of 75.9% and 87.9% and a per-lesion specificity of 87.5% and 86.2%, respectively. Conclusion The use of ancillary features in combination with major features increases the sensitivity while preserving a high specificity for the diagnosis of HCC.

Laparoscopic versus open parenchymal preserving liver resections in the posterosuperior segments: a case-matched study.

BACKGROUND: Patients with lesions in the posterosuperior (PS) segments of the liver have been considered poor candidates for laparoscopic liver resection (LLR). This study aims to compare short-term outcomes of LLR and open liver resections (OLR) in the PS segments. METHODS: This multicenter study consisted of all patients who underwent LLR in the PS segments and all patients who underwent OLR in the PS segments between October 2011 and July 2016. Laparoscopic cases were case-matched with those who had an identical open procedure during the same period based on tumor location (same segment) and the Brisbane classification of the resection. Demographics, comorbid factors, perioperative outcomes, short-term outcomes, necessity of adjuvant chemotherapy, and the interval between surgery and initiation of adjuvant chemotherapy were compared between the two groups. Data were retrieved from a prospectively maintained electronic database. RESULTS: Both groups were comparable for age, sex, ASA score, maximum tumor diameter, and number of patients with additional liver resections outside the posterior segments. Operative time was similar in both groups (median 140 min; p = 0.92). Blood loss was less in the LLR-group (median: 150 vs. 300 ml in OLR-group). Median hospital stay was 6 days in both groups. There was no significant difference in postoperative complications (OLR-group: 31.4% vs. LLR-group: 25.7%; p = 0.60). There was no significant difference in R0 resections (LLR: 97.2 vs. 100% in OLR; p = 1.00). Tumor-free margins were less in the LLR group (LLR: 5 vs. 9.5 mm in OLR; p = 0.012). Patients undergoing LLR were treated with chemotherapy sooner compared to those undergoing OLR (41 vs. 56 days, p = 0.02). CONCLUSION: This study suggests that laparoscopic parenchymal preserving liver resections in the PS segments can be performed with comparable short-term outcomes as similar OLR. The shorter interval to chemotherapy might provide long-term oncologic benefits in patients who underwent LLR.

Prediction of Hepatocellular Carcinoma Recurrence Beyond Milan Criteria After Resection: Validation of a Clinical Risk Score in an International Cohort.

OBJECTIVE: This study aims to validate a previously reported recurrence clinical risk score (CRS). SUMMARY OF BACKGROUND DATA: Salvage transplantation after hepatocellular carcinoma (HCC) resection is limited to patients who recur within Milan criteria (MC). Predicting recurrence patterns may guide treatment recommendations. METHODS: An international, multicenter cohort of R0 resected HCC patients were categorized by MC status at presentation. CRS was calculated by assigning 1 point each for initial disease beyond MC, multinodularity, and microvascular invasion. Recurrence incidences were estimated using competing risks methodology, and conditional recurrence probabilities were estimated using the Bayes theorem. RESULTS: From 1992 to 2015, 1023 patients were identified, of whom 613 (60%) recurred at a median follow-up of 50 months. CRS was well validated in that all 3 factors remained independent predictors of recurrence beyond MC (hazard ratio 1.5-2.1, all P < 0.001) and accurately stratified recurrence risk beyond MC, ranging from 19% (CRS 0) to 67% (CRS 3) at 5 years. Among patients with CRS 0, no other factors were significantly associated with recurrence beyond MC. The majority recurred within 2 years. After 2 years of recurrence-free survival, the cumulative risk of recurrence beyond MC within the next 5 years for all patients was 14%. This risk was 12% for patients with initial disease within MC and 17% for patients with initial disease beyond MC. CONCLUSIONS: CRS accurately predicted HCC recurrence beyond MC in this international validation. Although the risk of recurrence beyond MC decreased over time, it never reached zero.

Tumor-Associated Macrophage Infiltration in Colorectal Cancer Liver Metastases is Associated With Better Outcome.

BACKGROUND: Tumor-associated macrophages (TAMs) support growth in most human cancers, with the notable exception of colorectal adenocarcinoma, in which TAM infiltration of primary tumors is correlated with a better outcome. The importance of TAMs in colorectal liver metastases (CLM) is unknown. METHODS: Using a tissue microarray of CLM resected at their institution from 1998 to 2000, the authors quantified immune marker expression by immunohistochemistry (IHC) using Metamorph Image Analysis software. Findings showed that CD68, CD3, CD4, CD8, FoxP3, and MHC-I were correlated with overall survival (OS) and disease-free survival (DFS). RESULTS: Tumor cores from 158 patients were analyzed. The median follow-up period was 117 months for survivors (n = 39). The univariate analysis showed a significant positive association between DFS and CD4+ (p = 0.025) and CD68+ (p = 0.007). The findings showed a significant positive correlation of OS with CD4+ (p = 0.042), whereas the correlation with CD68+ was not significant (p = 0.17). Cutoffs were determined to dichotimize each marker for the highest log-rank statistic. Patients with CD4high had a median OS of 115 months and DFS of 41 months (p = 0.007 compared with 40 and 16 months, respectively, for patients with CD4low (p = 0.022). Patients with CD68high had a median OS of 50 months and a median DFS of 25 months (p = 0.67) compared with 43 and 15 months (p = 0.028). In the multivariate analysis of factors affecting DFS, high CD68 was associated with longer DFS (hazard ratio [HR], 0.63, 95% confidence interval [CI], 0.43-0.94; p = 0.02), independently of clinicopathologic variables and CD4. CONCLUSIONS: High TAM infiltration in resected CLM is associated with better outcome, independently of known clinicopathologic and immune predictors. This suggests that TAM depletion, which is being tested clinically in other cancers, may be detrimental in CLM.

Deep Learning: A Primer for Radiologists.

Deep learning is a class of machine learning methods that are gaining success and attracting interest in many domains, including computer vision, speech recognition, natural language processing, and playing games. Deep learning methods produce a mapping from raw inputs to desired outputs (eg, image classes). Unlike traditional machine learning methods, which require hand-engineered feature extraction from inputs, deep learning methods learn these features directly from data. With the advent of large datasets and increased computing power, these methods can produce models with exceptional performance. These models are multilayer artificial neural networks, loosely inspired by biologic neural systems. Weighted connections between nodes (neurons) in the network are iteratively adjusted based on example pairs of inputs and target outputs by back-propagating a corrective error signal through the network. For computer vision tasks, convolutional neural networks (CNNs) have proven to be effective. Recently, several clinical applications of CNNs have been proposed and studied in radiology for classification, detection, and segmentation tasks. This article reviews the key concepts of deep learning for clinical radiologists, discusses technical requirements, describes emerging applications in clinical radiology, and outlines limitations and future directions in this field. Radiologists should become familiar with the principles and potential applications of deep learning in medical imaging. ©RSNA, 2017.

Phenotype and function of T cells infiltrating visceral metastases from gastrointestinal cancers and melanoma: implications for adoptive cell transfer therapy.

Adoptive cell transfer of tumor-infiltrating lymphocytes (TILs) can mediate cancer regression in patients with metastatic melanoma, but whether this approach can be applied to common epithelial malignancies remains unclear. In this study, we compared the phenotype and function of TILs derived from liver and lung metastases from patients with gastrointestinal (GI) cancers (n = 14) or melanoma (n = 42). Fewer CD3(+) T cells were found to infiltrate GI compared with melanoma metastases, but the proportions of CD8(+) cells, T cell differentiation stage, and expression of costimulatory molecules were similar for both tumor types. Clinical-scale expansion up to ~50 × 10(9) T cells on average was obtained for all patients with GI cancer and melanoma. From GI tumors, however, TIL outgrowth in high-dose IL-2 yielded 22 ± 1.4% CD3(+)CD8(+) cells compared with 63 ± 2.4% from melanoma (p < 0.001). IFN-γ ELISA demonstrated MHC class I-mediated reactivity of TIL against autologous tumor in 5 of 7 GI cancer patients tested (9% of 188 distinct TIL cultures) and in 9 of 10 melanoma patients (43% of 246 distinct TIL cultures). In these assays, MHC class I-mediated up-regulation of CD137 (4-1BB) expression on CD8(+) cells suggested that 0-3% of TILs expanded from GI cancer metastases were tumor-reactive. This study implies that the main challenge to the development of TIL adoptive cell transfer for metastatic GI cancers may not be the in vitro expansion of bulk TILs, but the ability to select and enrich for tumor-reactive T cells.

Impact of the delay in cryopreservation timing during biobanking procedures on human liver tissue metabolomics.

The liver is a highly specialized organ involved in regulating systemic metabolism. Understanding metabolic reprogramming of liver disease is key in discovering clinical biomarkers, which relies on robust tissue biobanks. However, sample collection and storage procedures pose a threat to obtaining reliable results, as metabolic alterations may occur during sample handling. This study aimed to elucidate the impact of pre-analytical delay during liver resection surgery on liver tissue metabolomics. Patients were enrolled for liver resection during which normal tissue was collected and snap-frozen at three timepoints: before transection, after transection, and after analysis in Pathology. Metabolomics analyses were performed using 1H Nuclear Magnetic Resonance (NMR) and Liquid Chromatography-Mass Spectrometry (LC-MS). Time at cryopreservation was the principal variable contributing to differences between liver specimen metabolomes, which superseded even interindividual variability. NMR revealed global changes in the abundance of an array of metabolites, namely a decrease in most metabolites and an increase in ß-glucose and lactate. LC-MS revealed that succinate, alanine, glutamine, arginine, leucine, glycerol-3-phosphate, lactate, AMP, glutathione, and NADP were enhanced during cryopreservation delay (all p<0.05), whereas aspartate, iso(citrate), ADP, and ATP, decreased (all p<0.05). Cryopreservation delays occurring during liver tissue biobanking significantly alter an array of metabolites. Indeed, such alterations compromise the integrity of metabolomic data from liver specimens, underlining the importance of standardized protocols for tissue biobanking in hepatology.

Defining melanoma combination therapies that provide senolytic sensitivity in human melanoma cells.

Malignant Melanoma that resists immunotherapy remains the deadliest form of skin cancer owing to poor clinically lasting responses. Alternative like genotoxic or targeted chemotherapy trigger various cancer cell fates after treatment including cell death and senescence. Senescent cells can be eliminated using senolytic drugs and we hypothesize that the targeted elimination of therapy-induced senescent melanoma cells could complement both conventional and immunotherapies. We utilized a panel of cells representing diverse mutational background relevant to melanoma and found that they developed distinct senescent phenotypes in response to treatment. A genotoxic combination therapy of carboplatin-paclitaxel or irradiation triggered a mixed response of cell death and senescence, irrespective of BRAF mutation profiles. DNA damage-induced senescent melanoma cells exhibited morphological changes, residual DNA damage, and increased senescence-associated secretory phenotype (SASP). In contrast, dual targeted inhibition of Braf and Mek triggered a different mixed cell fate response including senescent-like and persister cells. While persister cells could reproliferate, senescent-like cells were stably arrested, but without detectable DNA damage and senescence-associated secretory phenotype. To assess the sensitivity to senolytics we employed a novel real-time imaging-based death assay and observed that Bcl2/Bcl-XL inhibitors and piperlongumine were effective in promoting death of carboplatin-paclitaxel and irradiation-induced senescent melanoma cells, while the mixed persister cells and senescent-like cells resulting from Braf-Mek inhibition remained unresponsive. Interestingly, a direct synergy between Bcl2/Bcl-XL inhibitors and Braf-Mek inhibitors was observed when used out of the context of senescence. Overall, we highlight diverse hallmarks of melanoma senescent states and provide evidence of context-dependent senotherapeutics that could reduce treatment resistance while also discussing the limitations of this strategy in human melanoma cells.

A senescence restriction point acting on chromatin integrates oncogenic signals.

We identify a senescence restriction point (SeRP) as a critical event for cells to commit to senescence. The SeRP integrates the intensity and duration of oncogenic stress, keeps a memory of previous stresses, and combines oncogenic signals acting on different pathways by modulating chromatin accessibility. Chromatin regions opened upon commitment to senescence are enriched in nucleolar-associated domains, which are gene-poor regions enriched in repeated sequences. Once committed to senescence, cells no longer depend on the initial stress signal and exhibit a characteristic transcriptome regulated by a transcription factor network that includes ETV4, RUNX1, OCT1, and MAFB. Consistent with a tumor suppressor role for this network, the levels of ETV4 and RUNX1 are very high in benign lesions of the pancreas but decrease dramatically in pancreatic ductal adenocarcinomas. The discovery of senescence commitment and its chromatin-linked regulation suggests potential strategies for reinstating tumor suppression in human cancers.

The effect of fluid overload in the presence of an epidural on the strength of colonic anastomoses.

BACKGROUND: Despite the beneficial effects of epidurals in intra-abdominal surgery, the incidence of anastomotic leak remains controversial when used. Moreover, studies have also shown that fluid overload may be deleterious to anastomoses. The purpose of this paper is to evaluate the effects of varying intraoperative fluid protocols, in the presence of an epidural, on the burst pressure strength of colonic anastomoses. METHODS: An epidural was installed in 18 rabbits, divided into three groups. Group 1 received 30 mL/kg/h Ringer's lactate, Group 2 received 100 mL/kg/h Ringer's lactate, and Group 3 received 30 mL/kg/h Pentaspan. Two colo-colonic anastomoses were performed per rabbit. On postoperative day 7 the anastomoses were resected and their burst pressures measured as a surrogate for anastomotic leak. RESULTS: When comparing the average burst pressures of all three groups, there was a significant difference (P = 0.04). The anastomoses in the 100 mL/kg/h Ringer's lactate group were shown to be the weakest, with 64% of the anastomoses having burst under 120 mm Hg. The rabbits hydrated with Pentaspan had the highest strength, with no anastomoses bursting under 120 mm Hg. This translated into significant burst pressure differences (P = 0.02) between Group 2 and Group 3. CONCLUSION: These results suggest that fluid overload with a crystalloid, in the presence of an epidural, may be deleterious to the healing of colonic anastomoses, creating a higher risk of anastomotic leak. Intraoperative resuscitation should thus focus on goal-directed euvolemia with appropriate amounts of colloids and/or crystalloids to prevent the risk of weakening anastomoses, especially in patients with epidurals.

How Social Responses to Child Sexual Abuse and Intimate Partner Violence Affect Homelessness Among Women in Two Rural Regions With Resource-Based Economies in Eastern Quebec.

This study presents findings from a qualitative study conducted in two relatively remote, primarily rural regions of the Canadian province of Quebec whose resource-based economic structures exacerbate inequalities between men and women. The purpose of this study was to understand how violence and homelessness intertwine in women's life courses in such regions. On the basis of past research showing that gender socialization around traditional roles and conservative values is particularly tenacious in non-urban areas, we conducted life-course interviews with 22 women in 13 different towns and villages of these two regions. Our content analysis of these interviews showed that specific social responses have forced women to maintain relationships with their aggressors or with people who have protected them, thus relegating these women's lives to the private sphere while reducing their opportunities for social participation in the public sphere. These social responses, together with women's economic and social disadvantages in these regions, were also the main factors that explain homelessness experienced by the participants in this study. Our analysis of these responses illustrates the patriarchal social structure of power in these regions, which is perpetuated in the interpersonal, institutional, and representational dimensions and keeps women in precarious, subordinate social positions, while ostracizing or punishing women who try to resist.

Metabolomics-Guided Identification of a Distinctive Hepatocellular Carcinoma Signature.

BACKGROUND: Hepatocellular carcinoma (HCC) is a major contributor to cancer-related morbidity and mortality burdens globally. Given the fundamental metabolic activity of hepatocytes within the liver, hepatocarcinogenesis is bound to be characterized by alterations in metabolite profiles as a manifestation of metabolic reprogramming. METHODS: HCC and adjacent non-tumoral liver specimens were obtained from patients after HCC resection. Global patterns in tissue metabolites were identified using non-targeted 1H Nuclear Magnetic Resonance (1H-NMR) spectroscopy whereas specific metabolites were quantified using targeted liquid chromatography-mass spectrometry (LC/MS). RESULTS: Principal component analysis (PCA) within our 1H-NMR dataset identified a principal component (PC) one of 53.3%, along which the two sample groups were distinctively clustered. Univariate analysis of tissue specimens identified more than 150 metabolites significantly altered in HCC compared to non-tumoral liver. For LC/MS, PCA identified a PC1 of 45.2%, along which samples from HCC tissues and non-tumoral tissues were clearly separated. Supervised analysis (PLS-DA) identified decreases in tissue glutathione, succinate, glycerol-3-phosphate, alanine, malate, and AMP as the most important contributors to the metabolomic signature of HCC by LC/MS. CONCLUSIONS: Together, 1H-NMR and LC/MS metabolomics have the capacity to distinguish HCC from non-tumoral liver. The characterization of such distinct profiles of metabolite abundances underscores the major metabolic alterations that result from hepatocarcinogenesis.

Homogeneity in immune features between colorectal liver metastases better identifies patients with good prognosis compared to pathological response to preoperative chemotherapy.

In colorectal cancer liver metastases (CRLM), the density of tumor-infiltrating lymphocytes, the expression of class I major histocompatibility complex (MHC-I), and the pathological response to preoperative chemotherapy have been associated with oncological outcomes after complete resection. However, the prognostic significance of the heterogeneity of these features in patients with multiple CRLMs remains under investigation. We used a tissue microarray of 220 mismatch repair-gene proficient CRLMs resected in 97 patients followed prospectively to quantify CD3+ T cells and MHC-I by immunohistochemistry. Histopathological response to preoperative chemotherapy was assessed using standard scoring systems. We tested associations between clinical, immunological, and pathological features with oncologic outcomes. Overall, 29 patients (30.2%) had CRLMs homogeneous for CD3+ T cell infiltration and MHC-I. Patients with immune homogeneous compared to heterogeneous CRLMs had longer median time to recurrence (TTR) (30 vs. 12 months, p = .0018) and disease-specific survival (DSS) (not reached vs. 48 months, p = .0009). At 6 years, 80% of the patients with immune homogeneous CRLMs were still alive. Homogeneity of response to preoperative chemotherapy was seen in 60 (61.9%) and 69 (80.2%) patients according to different grading systems and was not associated with TTR or DSS. CD3 and MHC-I heterogeneity was independent of response to pre-operative chemotherapy and of other clinicopathological variables for their association with oncological outcomes. In patients with multiple CRLMs resected with curative intent, similar adaptive immune features seen across metastases could be more informative than pathological response to pre-operative chemotherapy in predicting oncological outcomes.