CD74 supports accumulation and function of regulatory T cells in tumors.

Regulatory T cells (Tregs) are plastic cells playing a pivotal role in the maintenance of immune homeostasis. Tregs actively adapt to the microenvironment where they reside; as a consequence, their molecular and functional profiles differ among tissues and pathologies. In tumors, the features acquired by Tregs remains poorly characterized. Here, we observe that human tumor-infiltrating Tregs selectively overexpress CD74, the MHC class II invariant chain. CD74 has been previously described as a regulator of antigen-presenting cell biology, however its function in Tregs remains unknown. CD74 genetic deletion in human primary Tregs reveals that CD74KO Tregs exhibit major defects in the organization of their actin cytoskeleton and intracellular organelles. Additionally, intratumoral CD74KO Tregs show a decreased activation, a drop in Foxp3 expression, a low accumulation in the tumor, and consistently, they are associated with accelerated tumor rejection in preclinical models in female mice. These observations are unique to tumor conditions as, at steady state, CD74KO-Treg phenotype, survival, and suppressive capacity are unaffected in vitro and in vivo. CD74 therefore emerges as a specific regulator of tumor-infiltrating Tregs and as a target to interfere with Treg anti-tumor activity.

Hyperactivation of the JAK2/STAT5 Signaling Pathway and Evaluation of Baricitinib Treatment Among Patients With Eosinophilic Cellulitis.

Importance: The pathogenesis of eosinophilic cellulitis (EC) is poorly understood, limiting available treatment options. The current treatment paradigm focuses on delayed type 2 hypersensitivity reaction to various triggers. Objective: To gain further insight into the nature of EC inflammation and into the cellular signal transduction pathways that are activated in the context of EC. Design, Setting, and Participants: This case series was conducted in Lyon, France, from January 2018 to December 2021. Analysis of archival skin biopsy samples from patients with EC and from healthy control participants was performed using histology, Janus kinase (JAK)-signal transducer and activator of transcription (STAT) immunohistochemistry, and gene profiling. Data analysis was conducted between January 2020 and January 2022. Main Outcomes and Measures: Pruritus (visual analog score), percentage of body surface area with lesional skin, and RNA transcripts of inflammatory biomarkers from the skin (threshold cycle) were assessed in 1 index patient with refractory EC who received oral JAK1/JAK2 inhibitor baricitinib (4 mg/d). Results: This study included samples from 14 patients with EC (7 men and 7 women) and 8 healthy control participants (4 men and 4 women). The mean (SD) age of patients was 52 (20) years. Marked type 2 inflammation (chemokines CCL17, CCL18, and CCL26 and interleukin 13) with preferential activation of the JAK1/JAK2-STAT5 pathways in EC lesions was observed. In the 1 index patient with refractory EC, complete clinical remission of skin lesions was observed after 1 month of treatment with baricitinib. Conclusions and Relevance: These findings suggest that EC is a type 2 inflammatory disease with preferential activation of the JAK1/JAK2-STAT5 pathways. In addition, these results suggest the potential of treatment approaches targeting JAK1/JAK2 for patients with EC.

Noncanonical splicing junctions between exons and transposable elements represent a source of immunogenic recurrent neo-antigens in patients with lung cancer.

Although most characterized tumor antigens are encoded by canonical transcripts (such as differentiation or tumor-testis antigens) or mutations (both driver and passenger mutations), recent results have shown that noncanonical transcripts including long noncoding RNAs and transposable elements (TEs) can also encode tumor-specific neo-antigens. Here, we investigate the presentation and immunogenicity of tumor antigens derived from noncanonical mRNA splicing events between coding exons and TEs. Comparing human non-small cell lung cancer (NSCLC) and diverse healthy tissues, we identified a subset of splicing junctions that is both tumor specific and shared across patients. We used HLA-I peptidomics to identify peptides encoded by tumor-specific junctions in primary NSCLC samples and lung tumor cell lines. Recurrent junction-encoded peptides were immunogenic in vitro, and CD8+ T cells specific for junction-encoded epitopes were present in tumors and tumor-draining lymph nodes from patients with NSCLC. We conclude that noncanonical splicing junctions between exons and TEs represent a source of recurrent, immunogenic tumor-specific antigens in patients with NSCLC.

Impact of mismatch repair deficiency on tumour regression grade after neoadjuvant chemotherapy in localized gastroesophageal adenocarcinoma.

BACKGROUND: The use of neoadjuvant chemotherapy (NAC) in patients with mismatch repair (MMR) deficient (dMMR) localized gastric and oeso-gastric junction (OGJ) adenocarcinoma is subject of debate. Histological response assessment might help to better evaluate the impact of dMMR on response to NAC. METHODS: Patients with localized gastric/OGJ adenocarcinoma resected after NAC were retrospectively identified. MMR protein expression status was assessed by immunohistochemistry. The primary objective was the frequency of histological responders to NAC defined by tumour regression grade (TRG) using Mandard's (TRG1-2) and Becker's (TRG1) classifications, according to the MMR status. RESULTS: In total, 247 patients with 43 dMMR and 204 pMMR gastric/OGJ adenocarcinoma were identified. Among dMMR tumours, 18 (42%) arose from the OGJ. Histological response (Becker TRG1-2) was observed for 28% and 35% of dMMR and pMMR tumours, respectively (p = 0.35). Similar results were observed with Mandard classification. With a median follow-up of 37.5 months, median disease-free and overall survival were not reached for the dMMR group. CONCLUSION: Histological response after NAC in patients with localized dMMR gastric/OGJ adenocarcinoma is not statistically different to those with pMMR tumours. This study provides additional data for the discussion about avoiding NAC in patients with dMMR gastric/OGJ adenocarcinomas.

Spatial Positioning and Matrix Programs of Cancer-Associated Fibroblasts Promote T-cell Exclusion in Human Lung Tumors.

It is currently accepted that cancer-associated fibroblasts (CAF) participate in T-cell exclusion from tumor nests. To unbiasedly test this, we used single-cell RNA sequencing coupled with multiplex imaging on a large cohort of lung tumors. We identified four main CAF populations, two of which are associated with T-cell exclusion: (i) MYH11+αSMA+ CAF, which are present in early-stage tumors and form a single cell layer lining cancer aggregates, and (ii) FAP+αSMA+ CAF, which appear in more advanced tumors and organize in patches within the stroma or in multiple layers around tumor nests. Both populations orchestrate a particular structural tissue organization through dense and aligned fiber deposition compared with T cell-permissive CAF. Yet they produce distinct matrix molecules, including collagen IV (MYH11+αSMA+ CAF) and collagen XI/XII (FAP+αSMA+ CAF). Hereby, we uncovered unique molecular programs of CAF driving T-cell marginalization, whose targeting should increase immunotherapy efficacy in patients bearing T cell-excluded tumors. SIGNIFICANCE: The cellular and molecular programs driving T-cell marginalization in solid tumors remain unclear. Here, we describe two CAF populations associated with T-cell exclusion in human lung tumors. We demonstrate the importance of pairing molecular and spatial analysis of the tumor microenvironment, a prerequisite to developing new strategies targeting T cell-excluding CAF. See related commentary by Sherman, p. 2501. This article is highlighted in the In This Issue feature, p. 2483.

Prognostic role of infracentimetric colorectal liver metastases.

BACKGROUND: The number of lesions and the size of the largest (CRLMmax) have been widely investigated as prognostic factors in patients with colorectal liver metastases (CRLM). The aim of the present study was to assess whether, in patients undergoing curative liver resection, the presence of infracentimetric lesions could affect recurrence-free survival (RFS) and overall survival (OS). METHODS: Patients who underwent a liver resection for CRLM between 2001 and 2019 were included. The size of CRLM was measured on the surgical specimen. The best cut-off of the smallest lesion (CRLMmin) associated with RFS was determined through the time-dependent ROC analysis. A multivariate Cox regression analysis was carried out. RESULTS: Overall, 227 patients were included. Median follow-up time was 50 months [IQR 26-84]. Recurrence occurred for 151 (66.5%) patients (liver recurrence in 67.5%, while exclusive extra-hepatic recurrence in 32.5%). The best cut-off for CRLMmin associated with RFS was 9 mm, with 12- and 24-month td-AUC 0.56 and 0.52 respectively. CRLMmin ≤ 9 mm was found to be an independent prognostic factor that impairs RFS at multivariate analysis (HR 1.534 (1.02-2.32), p = 0.042). In particular, CRLMmin ≤ 9 mm was correlated with impaired hepatic RFS (HR 1.860 (1.15-3.01), p = 0.011), but not extra-hepatic RFS. CONCLUSIONS: Infracentimetric metastases (≤ 9 mm) are an independent prognostic factor that impairs hepatic RFS. This result suggests the potential benefit of neoadjuvant chemotherapy (CT) also in selected patients with initially resectable lesions, in case of CRLM ≤ 9 mm on preoperative imaging.

Prognostic impact of splenic vessel involvement and tumor size in distal pancreatectomy for adenocarcinoma: a retrospective multicentric cohort study.

PURPOSE: Splenic vessel involvement occurs frequently in pancreatic ductal adenocarcinoma (PDAC) of the body and the tail (B/T) but the impact on survival is unknown. We assessed the influence of radiological and pathologic involvement of splenic artery (p-SA +) and vein (p-SV +) on patient outcomes after distal pancreatectomy (DP) for PDAC. METHODS: From 2013 to 2019, all DP for PDAC in five centers were included. Factors associated with overall (OS) and disease-free (DFS) survival were identified. RESULTS: Among the 76 patients included, 5 (6.6%) had p-SA + only, 11 (14.5%) had p-SV + only, and 24 (31.6%) had both p-SA + and p-SV + . The preoperative CT-scan accuracy to predict p-SV + and p-SA + was high (sensitivity: 91.4% and 82.8%, respectively; negative predictive value: 89.7% and 88.3%, respectively). The 5-year OS and DFS rates were 3.9% and 8.3%, respectively. Multivariate analysis identified splenic vessel involvement (i.e., p-SA + or p-SV + , or both p-SA + and p-SV +) as the only independent factor influencing DFS (HR 4.04; 95% CI [1.22-13.44], p = 0.023). Tumor size ≥ 30 mm was the only independent factor influencing OS (HR 4.04; 95% CI [1.26-12.95], p = 0.019) and was associated with a high risk of p-SA + (p = 0.001) and p-SV + (p < 0.001). CONCLUSION: Tumor size ≥ 30 mm and splenic vessel involvement occurred in more than half of the patients who underwent DP for PDAC and had negative impact on long-term survival. Preoperative CT-scan was reliable to identify splenic vessel involvement in B/T PDAC. Large tumor size and radiological splenic vessel involvement could be taken into account to propose a neoadjuvant treatment.

Quality of oncological resection criteria in minimally invasive esophagectomy.

BACKGROUND: Even though minimally invasive esophageal surgery (MIE) is spreading, questions remain regarding its oncological outcomes. The aim of this study was to assess the quality of oncological resection criteria in MIE. METHODS: All patients undergoing a two-way Ivor Lewis esophagectomy for esophageal or junctional cancer between 2010 and 2020 in a single tertiary upper gastrointestinal surgery ward were analyzed retrospectively. The following oncological criteria were analyzed: lymph node (LN) harvest and location, positive lymph node rate, margins, and R0 rates. They were compared between the MIE group (thoracoscopy + laparoscopy) and the hybrid group (H/O, thoracotomy + laparoscopy). RESULTS: Among the 240 patients included, 34 (14%) had MIE and 206 a hybrid esophagectomy. Main surgical indication was lower thoracic adenocarcinoma and the rate of neoadjuvant treatments administered (chemotherapy or chemoradiotherapy) was comparable between both groups (p = 1.0). LN harvest was significantly higher in the MIE group (31 ± 9 vs. 28 ± 9, p = 0.04) as well as thoracic LN harvest (14 ± 7 vs. 11 ± 5, p = 0.002). When analyzing patients according to T stage and response to neoadjuvant treatments, patients with T1 and T2 tumors and patients with a poor pathological response (TRG3, 4, 5) had a significantly higher LN harvest when undergoing a minimally invasive approach (p = 0.021 and p = 0.01, respectively). Positive LN rates (1.26 ± 3.63 in the MIE group vs. 1.60 ± 2.84 in the H/O group, p = 0.061), R0 rates (97% vs. 98.5%, p = 0.46) as well as proximal (p = 0.083), distal (p = 0.063), and lateral (p = 0.15) margins were comparable between both approaches. CONCLUSION: MIE seems oncologically safe and may even be better than the open approach in terms of LN harvest especially in patients with T1 and T2 tumors and in poor responders.

Incomplete Carney Triad: A Surgical Case of a Rare Syndrome.

We describe a 36-year-old woman with multiple gastric gastrointestinal stromal tumors, hepatic and lymphatic metastasis, and a mediastinal paraganglioma as a presentation of an incomplete Carney triad. We present our therapeutic approach, with emphasis on the surgical and oncologic specificities of this syndrome.

Optimal Surgical Outcome of Minimally Invasive Partial Nephrectomy (MIPN) Based on an Early Postoperative Estimated Glomerular Filtration Rate (eGFR).

PURPOSE OF REVIEW: To compare laparoscopic partial nephrectomy (LPN) and robot-assisted partial nephrectomy (RAPN) performed in two European tertiary centers using the classic optimal surgical definition - "MIC" - and a new optimal surgical definition: the "Novel TRIFECTA" (NT) concept. We sought to strengthen the PN evidence and to test the NT's performance. RECENT FINDINGS: The study population comprehended 505 cases of localized kidney cancer from two tertiary centers between 2012 and 2019. The NT achievement was higher in the RAPN group when compared to LPN (70.5 vs. 87.4%; p = 0.004), while no differences were found when considering the MIC criteria. Also, a similar high-grade complications rate (Clavien-Dindo > III) and operative time (105 min vs. 100 min; p = NS) were found. In the multivariable regression, the RAPN approach was a predictor of NT achievement (OR 2.45; p = 0.008). NT achievement was higher in the RAPN group, while similar results were found when evaluating the MIC criteria. The NT definition could be more sensitive to the individual-specific responses related to the PN.

Tertiary Lymphoid Structure-B Cells Narrow Regulatory T Cells Impact in Lung Cancer Patients.

The presence of tertiary lymphoid structures (TLS) in the tumor microenvironment is associated with better clinical outcome in many cancers. In non-small cell lung cancer (NSCLC), we have previously showed that a high density of B cells within TLS (TLS-B cells) is positively correlated with tumor antigen-specific antibody responses and increased intratumor CD4+ T cell clonality. Here, we investigated the relationship between the presence of TLS-B cells and CD4+ T cell profile in NSCLC patients. The expression of immune-related genes and proteins on B cells and CD4+ T cells was analyzed according to their relationship to TLS-B density in a prospective cohort of 56 NSCLC patients. We observed that tumor-infiltrating T cells showed marked differences according to TLS-B cell presence, with higher percentages of naïve, central-memory, and activated CD4+ T cells and lower percentages of both immune checkpoint (ICP)-expressing CD4+ T cells and regulatory T cells (Tregs) in the TLS-Bhigh tumors. A retrospective study of 538 untreated NSCLC patients showed that high TLS-B cell density was even able to counterbalance the deleterious impact of high Treg density on patient survival, and that TLS-Bhigh Treglow patients had the best clinical outcomes. Overall, the correlation between the density of TLS-Bhigh tumors with early differentiated, activated and non-regulatory CD4+ T cell cells suggest that B cells may play a central role in determining protective T cell responses in NSCLC patients.

The Immunoscore in Localized Urothelial Carcinoma Treated with Neoadjuvant Chemotherapy: Clinical Significance for Pathologic Responses and Overall Survival.

(1) Background-The five-year overall survival (OS) of muscle-invasive bladder cancer (MIBC) with neoadjuvant chemotherapy and cystectomy is around 50%. There is no validated biomarker to guide the treatment decision. We investigated whether the Immunoscore (IS) could predict the pathologic response to neoadjuvant chemotherapy and survival outcomes. (2) Methods-This retrospective study evaluated the IS in 117 patients treated using neoadjuvant chemotherapy for localized MIBC from six centers (France and Greece). Pre-treatment tumor samples were immunostained for CD3+ and CD8+ T cells and quantified to determine the IS. The results were associated with the response to neoadjuvant chemotherapy, time to recurrence (TTR), and OS. (3) Results-Low (IS-0), intermediate (IS-1-2), and high (IS-3-4) ISs were observed in 36.5, 43.7, and 19.8% of the cohort, respectively. IS was positively associated with a pathologic complete response (pCR; p-value = 0.0096). A high IS was found in 35.7% of patients with a pCR, whereas it was found in 11.3% of patients without a pCR. A low IS was observed in 48.4% of patients with no pCR and in 21.4% of patients with a pCR. Low-, intermediate-, and high-IS patients had five-year recurrence-free rates of 37.2%, 36.5%, and 72.6%, respectively. In the multivariable analysis, a high IS was associated with a prolonged TTR (high vs. low: p = 0.0134) and OS (high vs. low: p = 0.011). (4) Conclusions-This study showed the significant prognostic and predictive roles of IS regarding localized MIBC.

Contribution of resident and circulating precursors to tumor-infiltrating CD8+ T cell populations in lung cancer.

Tumor-infiltrating lymphocytes (TILs), in general, and especially CD8+ TILs, represent a favorable prognostic factor in non-small cell lung cancer (NSCLC). The tissue origin, regenerative capacities, and differentiation pathways of TIL subpopulations remain poorly understood. Using a combination of single-cell RNA and T cell receptor (TCR) sequencing, we investigate the functional organization of TIL populations in primary NSCLC. We identify two CD8+ TIL subpopulations expressing memory-like gene modules: one is also present in blood (circulating precursors) and the other one in juxtatumor tissue (tissue-resident precursors). In tumors, these two precursor populations converge through a unique transitional state into terminally differentiated cells, often referred to as dysfunctional or exhausted. Differentiation is associated with TCR expansion, and transition from precursor to late-differentiated states correlates with intratumor T cell cycling. These results provide a coherent working model for TIL origin, ontogeny, and functional organization in primary NSCLC.

Does Chemotherapy-Induced Liver Injury Impair Postoperative Outcomes After Laparoscopic Liver Resection for Colorectal Metastases?

BACKGROUND: Chemotherapy-associated liver injuries (CALI) have been associated with poor postoperative outcome after open liver resection. To date, no data concerning any correlation of CALI and laparoscopic liver resection (LLR) are available. In the present study, we evaluated the impact of CALI on short-term outcomes in patients undergoing LLR. MATERIALS AND METHODS: All patients who underwent in our department LLR for colorectal liver metastases (CRLM) from 2000 to 2016 were retrospectively reviewed. Patients were divided in 4 groups according to their pathological histology. In group 1 patients had normal liver parenchyma. Group 2 included patients with steatosis and steatohepatitis. Patients with sinusoidal obstruction syndrome (SOS) and nodular regenerative hyperplasia (NRH) were allocated to group 3, whereas the remaining with fibrosis and cirrhosis, were assigned to group 4. RESULTS: A total of 490 LLR for CRLM were included in the study. Perioperative details and morbidity did not differ significantly between the four groups. Subgroup analysis showed that NRH was associated with higher amount of blood loss (p = 0.043), overall (p = 0.021) and liver-specific morbidity (p = 0.039). CONCLUSION: NRH is a severe form of CALI that may worsen the short-term outcomes of patients undergoing LLR for CRLM. However, the remaining forms of CALI do not have a significant impact on perioperative outcomes after LLR.

Does the difficulty grade of laparoscopic liver resection for colorectal liver metastases correlate with long-term outcomes?

INTRODUCTION: Prognosis of patients with colorectal liver metastases (CRLM) is strongly correlated with the oncological outcome after liver resection. The aim of this study was to analyze the impact of laparoscopic liver resection (LLR) difficulty score (IMM difficulty score) on the oncological results in patients treated for CRLM. METHODS: All patients who underwent LLRs for CRLM from 2000 to 2016 in our department, were retrospectively reviewed. Data regarding difficulty classification, -according to the Institute Mutualiste Montsouris score (IMM)-, recurrence rate, recurrence-free survival (RFS), overall survival (OS) and data regarding margin status were analyzed. RESULTS: A total of 520 patients were included. Patients were allocated into 3 groups based on IMM difficulty score of the LLR they underwent: there were 227 (43,6%), 84 (16,2%) and 209 (40,2%) patients in groups I, II and III, respectively. The R1 resection rate in group I, II and III were 8,8% (20/227), 11,9% (10/84) and 12,4% (26/209) respectively (p = 0.841). Three- and 5-year RFS rates were 77% and 73% in group I, 58% and 51% in group II, 61% and 53% in group III, respectively (p = 0.038). Three and 5-year OS rates were 87% and 80% for group I, 77% and 66% for group II, 80% and 69% for group III respectively (p = 0.022). CONCLUSION: The higher LLR difficulty score correlates with significant morbidity and worse RFS and OS, although the more technically demanding and difficult cases are not associated with increased rates of positive resection margins and recurrence.