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In this study, we investigated the role of the Wnt/β-catenin signaling pathway in antitumor immune responses. We report that the concentration of secreted Wnt3a was significantly higher in conditioned medium from tumor or nontumor tissues obtained from all hepatocellular carcinoma or colorectal cancer patients tested, than in serum of healthy donors or patients. In addition, both Wnt3a and β-catenin were overexpressed by tumor-infiltrating and nontumor-infiltrating CD4+ or CD8+ T cells. The majority of these T cells expressed a dysfunctional effector memory Eomes+T-bet−phenotype that we defined as partially exhausted, because they performed effector functions (in terms of interferon-γ and tumor necrosis factor-α production, as well as CD107a mobilization) despite their PD-1 expression. Wnt3a/β-catenin signaling in T naïve cells in vitro recapitulated the T-cell setting in vivo. Indeed, the differentiation of cultured T naïve cells was arrested, producing cells that resembled the EomeshighT-betlowβ-cateninhigh T cells with moderate effector functions that infiltrated tumor and nontumor areas. Wnt3a blockade improved the capacity of T naïve cells to differentiate into effector cells in vitro. However, Wnt3a blockade did not affect the function and phenotype of differentiated, partially exhausted, tumor-infiltrating T cells ex vivo. Taken together, our data suggest that Wnt3a blockade halts the capacity of Wnt/β-catenin signaling to inhibit the differentiation of T naïve cells, but it does not restore the dysfunction of differentiated T cells, in the tumor setting. Cancer Immunol Res; 6(8); 941–52. ©2018 AACR.

Table S1. Characteristics of all enrolled patients (HCC=35, CRC=16), not previous treated with chemotherapy Table S2. List of all antibodies for FC analysis Figure S1: CD4 and CD8 T cells expressed high levels of PD1 in TUM district and showed mostly an effector memory phenotype in CRC Figure S2: Distribution of Wnt3a in serum, NTUM- or TUM-derived CM, and expression of Wnt3a/β-catenin axis in NTUM and TUM-infiltrating CD4 and CD8 T cells from CRC patients Figure S3: Analysis of Frizzled receptor 1 expression among CD4 and CD8 T cells in periphery, nontumor and tumor samples of HCC patients Figure S4: β-catenin+ tumor-infiltrating CD4 T cells in presence of anti-Wnt3a do not down-regulated TNF-α prduction

In our study, we investigated the role of CD39 on tumor-infiltrating CD8

In our study, we investigated the role of CD39 on tumor-infiltrating CD8+ T lymphocytes (CD8+ TILs) in colorectal, head and neck and pancreatic cancers. Partially confirming recent observations correlating the CD39 expression with T-cell exhaustion, we demonstrated a divergent functional activity in CD39+ CD8+ TILs. On the one hand, CD39+ CD8+ TILs (as compared to their CD39- counterparts) produced significantly lower IFN-γ and IL-2 amounts, expressed higher PD-1, and inversely correlated with perforin and granzyme B expression. On the other, they displayed a significantly higher proliferative capacity ex vivo that was inversely correlated with the PD-1 expression. Therefore, CD39+ CD8+ TILs, including those co-expressing the CD103 (a marker of T resident memory [TRM] cells), were defined as partially dysfunctional T cells that correlate with tumor patients with initial progression stages. Interestingly, our results identified for the first time a single nucleotide polymorphism (SNP rs10748643 A>G), as a genetic factor associated with CD39 expression in CD8+ TILs. Finally, we demonstrated that compounds inhibiting CD39-related ATPases improved CD39+ CD8+ T-cell effector function ex vivo, and that CD39+ CD8+ TILs displayed effective suppression function in vitro. Overall these data suggest that the SNP analysis may represent a suitable predictor of CD39+ CD8+ T-cell expression in cancer patients, and propose the modulation of CD39 as a new strategy to restore partially exhausted CD8+ TILs.

Background Intrapancreatic accessory spleen (IPAS) is an uncommon finding of pancreatic mass. Differential diagnosis with pancreatic tumor, especially with non-functional neuroendocrine tumor (NF-NET), may be very hard and sometimes it entails unnecessary surgery. A combination of CT scan, MRI, and nuclear medicine can confirm the diagnosis of IPAS. 68-Ga-Dotatoc PET/CT is the gold standard in NET diagnosis and it can allow to distinguish between IPAS and NET. Case presentation A 69-year-old man was admitted to our hospital for an incidental nodule in the tail of the pancreas with focal uptake of 68-Ga-dotatate at PET/CT. NET was suspected and open distal splenopancreatectomy was performed. Pathologic examination revealed an IPAS. Conclusion This is the second IPAS case in which a positive 68Ga-Dotatoc uptake led to a false diagnosis of pancreatic NET. Here is a proposal of a literature review.

In this study, we investigated the role of the Wnt/β-catenin signaling pathway in antitumor immune responses. We report that the concentration of secreted Wnt3a was significantly higher in conditioned medium from tumor or nontumor tissues obtained from all hepatocellular carcinoma or colorectal cancer patients tested, than in serum of healthy donors or patients. In addition, both Wnt3a and β-catenin were overexpressed by tumor-infiltrating and nontumor-infiltrating CD4+ or CD8+ T cells. The majority of these T cells expressed a dysfunctional effector memory Eomes+T-bet−phenotype that we defined as partially exhausted, because they performed effector functions (in terms of interferon-γ and tumor necrosis factor-α production, as well as CD107a mobilization) despite their PD-1 expression. Wnt3a/β-catenin signaling in T naïve cells in vitro recapitulated the T-cell setting in vivo. Indeed, the differentiation of cultured T naïve cells was arrested, producing cells that resembled the EomeshighT-betlowβ-cateninhigh T cells with moderate effector functions that infiltrated tumor and nontumor areas. Wnt3a blockade improved the capacity of T naïve cells to differentiate into effector cells in vitro. However, Wnt3a blockade did not affect the function and phenotype of differentiated, partially exhausted, tumor-infiltrating T cells ex vivo. Taken together, our data suggest that Wnt3a blockade halts the capacity of Wnt/β-catenin signaling to inhibit the differentiation of T naïve cells, but it does not restore the dysfunction of differentiated T cells, in the tumor setting. Cancer Immunol Res; 6(8); 941–52. ©2018 AACR.

Tregs can contribute to tumor progression by suppressing antitumor immunity. Exceptionally, in human colorectal cancer (CRC), Tregs are thought to exert beneficial roles in controlling pro-tumor chronic inflammation. The goal of our study was to characterize CRC-infiltrating Tregs at multiple levels, by phenotypical, molecular and functional evaluation of Tregs from the tumor site, compared to non-tumoral mucosa and peripheral blood of CRC patients. The frequency of Tregs was higher in mucosa than in blood, and further significantly increased in tumor. Ex vivo, those Tregs suppressed the proliferation of tumor-infiltrating CD8(+) and CD4(+) T cells. A differential compartmentalization was detected between Helios(high) and Helios(low) Treg subsets (thymus-derived versus peripherally induced): while Helios(low) Tregs were enriched in both sites, only Helios(high) Tregs accumulated significantly and specifically in tumors, displayed a highly demethylated TSDR region and contained high proportions of cells expressing CD39 and OX40, markers of activation and suppression. Besides the suppression of T cells, Tregs may contribute to CRC progression also through releasing IL-17, or differentiating into Tfr cells that potentially antagonize a protective Tfh response, events that were both detected in tumor-associated Tregs. Overall, our data indicate that Treg accumulation may contribute through multiple mechanisms to CRC establishment and progression.