Comparison of CT and gadoxetic acid-enhanced MRI with liver imaging reporting and data system to assess liver tumors before resection.

BACKGROUND/PURPOSE: Hepatocellular carcinoma (HCC) can be noninvasively diagnosed through dynamic computed tomography (CT) and magnetic resonance imaging (MRI). We compared the diagnostic performance of CT and gadoxetic acid-enhanced MRI (EOB-MRI) in categorizing tumors by using the 2018 version of the Liver Imaging Reporting And Data System (LI-RADS v2018) and assessing liver tumors before resection. METHODS: Data from a prospective cohort from October 2011 to March 2019 on 106 hepatic tumors in 96 patients with suspected malignancy were included in this study. We performed preoperative CT and EOB-MRI, and reviewed these images retrospectively. Ninety-seven tumors from 87 patients were pathologically diagnosed as HCC, and nine tumors were non-HCC. The clinical data, imaging characteristics, diagnostic performance, and outcomes of CT and EOB-MRI were analyzed and compared. RESULTS: EOB-MRI had more favorable diagnostic performance (area under curve: 0.920 vs. 0.868) and significantly higher sensitivity (86.87% vs. 69.70%, p = 0.005) than did CT. However, the specificity of EOB-MRI did not differ from that of CT (88.89% vs. 88.89%, p > 0.999). Fourteen (14.5%) patients with pathologically verified HCC had lesions categorized as LI-RADS 4 through CT and as LI-RADS 5 through EOB-MRI. Patients with EOB-MRI-categorized but not CT-categorized LI-RADS 5 lesions had significantly longer overall survival than did those with LI-RADS 4 lesions (p < 0.001). CONCLUSION: EOB-MRI had higher sensitivity than did CT in diagnosing HCC. Patients with EOB-MRI-categorized LI-RADS 5 lesions had more favorable outcomes than did those with LI-RADS 4 lesions after liver resection.

IL-6 restores dendritic cell maturation inhibited by tumor-derived TGF-ß through interfering Smad 2/3 nuclear translocation.

We previously found, in a canine transferable tumor model, that high concentration of IL-6 produced by tumor-infiltrating lymphocytes effectively restores the MHC expression of the tumor cells and T-cell activation inhibited by tumor-derived TGF-ß. This tumor also significantly suppresses monocyte-derived dendritic cells (DCs) differentiation and the functions of differentiated DCs with unknown mechanisms. In this study, we have demonstrated that a strong reaction of IL-6 was present to neutralize TGF-ß-down-regulated surface marker expression on DCs (MHC II, CD1a, CD40, CD80, CD83, CD86), TGF-ß-hampered DC functions and DC-associated T-cell activation. Western blotting and confocal microscopy results indicated that the presence of IL-6 markedly decreased the nuclear concentration of a TGF-ß signaling transducer, Smad 2/3. In addition, while Smad 7 is a potent molecule inhibiting Smad 2/3 nuclear translocation, no significant increase in Smad 7 gene expression upon addition of IL-6 in TGF-ß-pretreated DCs was detected, which suggested that the blockage of Smad 2/3 nuclear translocation by IL-6 did not occur through a Smad 7-inhibitory mechanism. In conclusion, IL-6 inhibited TGF-ß signaling and concomitantly antagonized the suppression activities of TGF-ß on DC maturation and activity. This study enables further understandings of host/cancer interactions an also provide hints facilitating improvements of DC-based cancer immunotherapy.

Transient downregulation of monocyte-derived dendritic-cell differentiation, function, and survival during tumoral progression and regression in an in vivo canine model of transmissible venereal tumor.

Tumors often target dendritic cells (DCs) to evade host immune surveillance. DC injury is reported in many rodent and human tumors but seldom in tumors of other mammals. Canine transmissible venereal tumor (CTVT), a unique and spontaneous cancer transmitted by means of viable tumor cells. CTVT causes manifold damage to monocyte-derived DCs. This cancer provides an in vivo model of cancer to study the role of monocyte-derived DCs during spontaneous regression. Using flow cytometry and real-time reverse-transcription polymerase chain reactions, we compared the expression of surface molecules on monocyte-derived DCs between normal dogs and dogs with CTVT. These markers were CD1a, CD83, costimulatory factors (CD40, CD80, and CD86), and major histocompatability complex classes I and II. In immature DCs (iDCs) and lipopolysaccharide-treated mature DCs (mDCs), the surface markers were mostly downregulated during tumoral progression and regression. The tumor lowered endocytic activity of iDCs, as reflected in dextran uptake, and decreased allogeneic mixed lymphocyte reactions of mDCs. In addition, it decreased the number of monocytes in the peripheral blood by 40%. The tumor substantially impaired the efficiency with which DCs were generated from monocytes and with which mDCs were generated from iDCs. We also found that progression-phase CTVT supernatants that were cultured for 48 h and that contained protein components killed both monocytes and DCs. Additionally, DC numbers were significantly lower in the draining lymph nodes in CTVT dogs than in normal dogs. In conclusion, CTVT caused devastating damage to monocyte-derived DCs; this might be one of its mechanisms for evading host immunity. Reestablishment of monocyte-derived DC activity by the host potentially might contribute to spontaneous tumoral regression. These findings provide insight into the extent of tumoral effects on host immune systems and responses. This information is useful for developing cancer immunotherapies.