Immunovascular classification of HCC reflects reciprocal interaction between immune and angiogenic tumor microenvironments.

BACKGROUND AND AIMS: Immune cells and tumor vessels constitute important elements in tumor tissue; however, their detailed relationship in human tumors, including HCC, is still largely unknown. Consequently, we expanded our previous study on the immune microenvironment of HCC and analyzed the relationship among the immune microenvironment, inflammatory/angiostatic factor expression, angiogenic factor expression, and tumor vessel findings, including vessels encapsulating tumor clusters (VETC) and macrotrabecular-massive (MTM) patterns. APPROACH AND RESULTS: We classified HCC into four distinct immunovascular subtypes (immune-high/angiostatic [IH/AS], immune-mid/angio-mid [IM/AM], immune-low/angiogenic [IL/AG], and immune-low/angio-low [IL/AL]). IH/AS, IM/AM, and IL/AG subtypes were associated with decreasing lymphocytic infiltration and increasing angiogenic factor expression and VETC/MTM positivity, reflecting their reciprocal interaction in the tumor microenvironment of HCC. IL/AG subtype was further characterized by CTNNB1 mutation and activation of Wnt/ß-catenin pathway. IL/AL subtype was not associated with increased lymphocyte infiltration or angiogenic factor expression. Prognostically, IH/AS subtype and VETC/MTM positivity were independently significant in two independent cohorts. Increased angiogenic factor expression was not necessarily associated with VETC/MTM positivity and poor prognosis, especially when inflammatory/angiostatic milieu coexisted around tumor vessels. These results may provide insights on the therapeutic effects of immunotherapy, antiangiogenic therapies, and their combinations. The potential of evaluating the immunovascular microenvironment in predicting the clinical effect of these therapies in nonresectable HCC needs to be analyzed in the future study. CONCLUSIONS: HCC can be classified into four distinct immunovascular subtypes (IH/AS, IM/AM, IL/AG, and IL/AL) that reflect the reciprocal interaction between the antitumor immune microenvironment and tumor angiogenesis. In addition to its clinicopathological significance, immunovascular classification may also provide pathological insights on the therapeutic effect of immunotherapy, antiangiogenic therapy, and their combination.

Immunovascular microenvironment in relation to prognostic heterogeneity of WNT/ß-catenin-activated hepatocellular carcinoma.

AIM: WNT/ß-catenin-activated hepatocellular carcinoma (W/B subclass HCC) is considered a molecularly homogeneous entity and has been linked to resistance to immunotherapy. However, recent studies have indicated possible heterogeneity in the immunovascular microenvironment in this subclass. We set out to test the hypothesis that specific immunovascular features might stratify W/B subclass HCCs into tumors having distinct aggressive natures. METHODS: In this study, we analyzed 352 resected HCCs including 78 immunohistochemically defined W/B subclass HCCs. The density of tumor-infiltrating CD3+ T cells and the area ratio of vessels encapsulating tumor clusters (VETC) were calculated on tissue specimens. The gene expressions of angiogenic factors were measured by quantitative reverse transcription-polymerase chain reaction. Disease-free survival (DFS) was assessed using multivariable Cox regression analyses. RESULTS: The T-cell density of W/B subclass HCCs was regionally heterogenous within tumor tissues, and focally reduced T-cell density was observed in areas with VETC. VETC-positivity (defined as VETC area ratio greater than 1%) was inversely associated with T-cell infiltration in both W/B subclass and non-W/B subclass HCCs. Fibroblast growth factor 2 (FGF2) gene expression was higher in W/B subclass than in non-W/B subclass HCCs. The VETC-positivity and low T-cell density correlated with increased expression of FGF2 in W/B subclass HCCs. Additionally, VETC-positive HCCs showed significantly shorter DFS in W/B subclass HCCs. CONCLUSIONS: In conclusion, the immune and vascular microenvironments are interrelated and are also correlated with clinicopathological heterogeneity in W/B subclass HCC. These results could inform clinical practice and translational research on the development of therapeutic stratification of HCCs.

Eosinophilic granulomatosis with polyangiitis and severe cardiac involvement in a patient surviving for 34 years.

INTRODUCTION: Many studies have reported a poor prognosis for eosinophilic granulomatosis with polyangiitis (EGPA) patients with cardiac involvement. CASE STUDY: A woman developed EGPA at 37 years of age, with weight loss, numbness in the right upper and lower extremities, muscle weakness, skin rash, abdominal pain, chest pain, an increased peripheral blood eosinophil count (4165/µL), and necrotizing vasculitis on peroneal nerve biopsy. The patient was treated with prednisolone, immunosuppressants, intravenous immune globulin, and mepolizumab, but she experienced many relapses, with chest pain, abdominal pain, numbness, and paralysis, over a long period. The patient died from aspiration pneumonia at 71 years of age after undergoing left total hip arthroplasty for left hip neck fracture. RESULTS: Autopsy showed bronchopneumonia in the lower lung lobes on both sides, as well as infiltration of inflammatory cells, including neutrophils and lymphocytes. There was no evidence of active vasculitis in either the lung or colon. At autopsy the heart showed predominantly subendocardial fibrosis and fatty infiltration, but no active vasculitis or eosinophilic infiltration. CONCLUSION: To our knowledge, there have been no autopsy reports of EGPA patients who have survived for 34 years with recurrent cardiac lesions. In this case, the cardiac involvement (active vasculitis and eosinophilic infiltration) had improved by the time of death.

Role of CC chemokine receptor 9 in the progression of murine and human non-alcoholic steatohepatitis.

BACKGROUND & AIMS: The number of patients with non-alcoholic steatohepatitis (NASH) is increasing globally. Recently, specific chemokine receptors have garnered interest as therapeutic targets in NASH. This is the first report to examine the role of the C-C chemokine receptor 9 (CCR9)/C-C chemokine receptor ligand 25 (CCL25) axis, and to reveal its therapeutic potential in NASH. METHODS: Patients with biopsy-proven non-alcoholic liver disease (NAFLD) were recruited and their serum and hepatic chemokine expression was examined. Furthermore, wild-type (WT) and Ccr9-/- mice were fed a high-fat high-cholesterol (HFHC) diet for 24 weeks to establish NASH. RESULTS: Serum CCL25, and hepatic CCR9 and CCL25 expression levels were increased in patients with NASH compared to healthy volunteers. Furthermore, Ccr9-/- mice were protected from HFHC diet-induced NASH progression both serologically and histologically. Flow cytometry and immunohistochemistry analysis showed that CCR9+CD11b+ inflammatory macrophages accumulated in the inflamed livers of HFHC diet-fed mice, while the number was reduced in Ccr9-/- mice. Consistent with human NASH livers, CCR9 was also expressed on hepatic stellate cells (HSCs) in mice with NASH, while CCR9-deficient HSCs showed less fibrogenic potential in vitro. Administration of a CCR9 antagonist hampered further fibrosis progression in mice with NASH, supporting its potential clinical application. Finally, we showed that CCR9 blockade attenuated the development of NAFLD-related hepatocellular carcinoma in HF diet-fed mice injected with diethylnitrosamine. CONCLUSIONS: These results highlight the role of the CCR9/CCL25 axis on macrophage recruitment and fibrosis formation in a murine NASH model, providing new insights into therapeutic strategies for NASH. LAY SUMMARY: Herein, we show that a specific chemokine axis involving a receptor (CCR9) and its ligand (CCL25) contributes to the progression of non-alcoholic steatohepatitis and carcinogenesis in humans and mice. Furthermore, treatment with a CCR9 antagonist ameliorates the development of steatohepatitis and holds promise for the treatment of patients with non-alcoholic steatohepatitis.

Quantification of intratumoral collagen and elastin fibers within hepatocellular carcinoma tissues finds correlations with clinico-patho-radiological features.

AIM: Emerging evidence suggests a promising role for tumor stromal factors in characterizing patients with various types of malignancies, including hepatocellular carcinoma (HCC). We quantified the amount of collagen and elastin fibers in HCC samples with the aim of clarifying the clinico-patho-radiological significance of fiber deposition in HCC. METHODS: We computed the amount of collagen and elastin fibers using digital image analysis of whole-slide images of Elastica van Gieson-stained tissues from 156 surgically resected HCCs. Furthermore, we assessed the correlations between the fiber content of HCC samples and clinical, pathological, and radiological features, including immunohistochemistry-based molecular subtypes and immunosubtypes. RESULTS: The intratumoral area ratio of collagen in HCC tissues (median 3.4%, range 0.1-22.2%) was more than threefold that of elastin (median 0.9%, range 0.1-9.0%); there was a strong positive correlation between the amounts of collagen and elastin. Higher levels of combined collagen and elastin were significantly associated with the confluent multinodular macroscopic tumor type, the absence of a fibrous capsule, intratumoral steatosis, scirrhous tumor stroma, dense inflammatory-cell infiltrates, and the biliary/stem cell markers-positive HCC subtype. The associations of higher collagen levels with radiological findings, including heterogeneous enhancement and persistent enhancement on dynamic computed tomography, were significant. In contrast, the associations of radiological findings with elastin fibers were not significant. Intratumoral fibrous stroma in HCC comprised septum-like and perisinusoidal fibrosis; these two forms represented distinct distribution patterns of fibers and fibroblasts. CONCLUSION: Quantitative analysis suggested that stromal fiber-rich HCCs likely represent a distinct clinico-patho-radiological entity.

Precision pathology analysis of the development and progression of hepatocellular carcinoma: Implication for precision diagnosis of hepatocellular carcinoma.

Outcomes for patients with hepatocellular carcinoma (HCC) remain poor because the condition is often unresponsive to the available treatments. Consequently, the early and precise diagnosis of HCC is crucial to achieve improvements in prognosis. For patients with chronic liver disease, the assessment of liver fibrosis is also important to ascertain both the staging of fibrosis and the risk of HCC occurrence. Early HCC was first described in 1991 in Japan and was defined internationally in 2009. As the concept of early HCC spread, the multistage hepatocarcinogenesis process became accepted. Consequently, improvements in imaging technology made the early diagnosis of HCC possible. At present, the most appropriate therapeutic strategy for HCC is determined using an integrated staging system that assesses the tumor burden, the degree of liver dysfunction and the patient performance status; however, pathological and molecular features are not taken into account. The recent introduction of several new therapeutic agents will change the treatment strategy for HCC. Against this background, HCC subclassification based on tumor cellular and microenvironmental characteristics will become increasingly important. In this review, we give an overview of how pathological analysis contributes to understanding the development and progression of HCC and establishing a precision diagnosis of HCC.

Telomerase reverse transcriptase (TERT) promoter mutation correlated with intratumoral heterogeneity in hepatocellular carcinoma.

Telomerase reverse transcriptase (TERT) promoter mutations are frequently observed in hepatocellular carcinoma (HCC); however, the impact of TERT promoter mutations (TPMs) on clinical features and morphological patterns in HCC remains unresolved. Using DNA extracted from 97 HCCs, correlations between TPM status and both the clinical features of HCC and the immunohistochemically-based subgroups were evaluated. Morphological tumor patterns were semi-quantitatively analyzed using hematoxylin and eosin-stained slides of the whole tumor cross-sectional area. The percentages of tumor area occupied by early, well, moderate and poor histological patterns were calculated as a homogeneity index. TPMs were observed in 53 of 97 (55%) HCCs and were significantly associated with older age (P = 0.018) and HCV-related background (P = 0.048). The biliary/stem cell marker-positive subgroup was less likely to have TPMs (29%) compared to the Wnt/ß-catenin signaling marker-positive subgroup (60%). In contrast to TPM-negative HCCs, TPM-positive HCCs clearly exhibited intratumoral morphological heterogeneity (0.800 ± 0.117 vs 0.927 ± 0.096, P < 0.0001), characterized by two or more heterogeneous histological patterns (P < 0.0001) and had more well or early differentiated histological patterns (P = 0.024). Our findings showed that intratumoral heterogeneity was strongly related to TPM-positive HCCs, which established novel roles of TPMs, and may improve our understanding particularly about HCC development and diagnosis.

Clinicopathological features of hepatocellular carcinoma with fatty change: Tumors with macrovesicular steatosis have better prognosis and aberrant expression patterns of perilipin and adipophilin.

The clinicopathological characteristics of steatosis in hepatocellular carcinoma (HCC) remain unclear. Here, we elucidate the features of macrovesicular steatosis (MaS) and microvesicular steatosis (MiS) in HCC and their relationships with background liver steatosis. A total of 165 HCC lesions were classified as MaS-HCC, MiS-HCC, or conventional HCC (cHCC) according to the cutoff value of 30% MaS or MiS in tumor cells. We analyzed the clinicopathological differences among these groups. MaS-HCC had less portal vein invasion, a higher proportion of HCC with intratumoral fibrosis, and a lower cumulative risk of recurrence than MiS-HCC or cHCC. Moreover, both MaS-HCC and MiS-HCC had lower incidences of hepatitis virus infection and higher levels of HbA1c than cHCC. Background liver steatosis was also higher in MaS-HCC than in cHCC. Immunohistochemical expression of perilipin (Plin1) and adipophilin (ADRP), major proteins expressed on lipid droplet membranes, revealed that almost all lipid droplets in HCC were Plin1 negative, whereas those in background liver were positive. In contrast, ADRP was expressed on lipid droplets in both HCC and background liver. We concluded that MaS-HCC and MiS-HCC were associated with metabolic abnormalities but exhibited different biologic behaviors. Furthermore, lipid droplets in HCC were pathophysiologically different from those in background liver.

Magnetic resonance imaging-guided targeted prostate biopsy: Comparison between computer-software-based fusion versus cognitive fusion technique in biopsy-naïve patients.

OBJECTIVE: To compare magnetic resonance imaging-guided cognitive fusion-targeted biopsies versus computer-software-based fusion-targeted biopsies in prostate biopsy-naïve patients. METHODS: This was a retrospective review of 298 consecutive patients, in which suspected clinically significant prostate cancer lesions were detected on pre-biopsy magnetic resonance imaging, and cognitive fusion-targeted biopsies or software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies was carried out. The positivity rates of any cancer and clinically significant prostate cancer, Gleason score, and maximum cancer core length were compared between the cognitive fusion-targeted biopsies and software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies groups. RESULTS: The any-cancer positivity rate was 79.6% (90/113 patients) in the cognitive fusion-targeted biopsies group and 84.8% (157/185 patients) in the software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies group (P = 0.516), and the clinically significant prostate cancer positivity rate was 72.5% (82/113 patients) in the cognitive fusion-targeted biopsies group and 75.7% (140/185 patients) in the software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies group (P = 0.498). Among the patients in which the largest lesion diameter on magnetic resonance imaging was ≤5.0 mm, the clinically significant prostate cancer positivity rate was 39.2% (11/28 patients) in the cognitive fusion-targeted biopsies group and 66.6% (24/36 patients) in the software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies group (P = 0.043). The median maximum cancer core length was 7.5 mm (0.25-16 mm) in the cognitive fusion-targeted biopsies group and 8 mm (0.2-19 mm) in the software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies group (P = 0.040). CONCLUSIONS: Software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies offers a greater detection rate for smaller targeted lesions and also superior ability to sample greater cancer core length compared with cognitive fusion-targeted biopsies. The present results suggest that software-guided magnetic resonance imaging-ultrasound fusion-targeted biopsies might improve biopsy outcomes compared with cognitive fusion-targeted biopsies.

Focal salvage low-dose-rate brachytherapy for recurrent prostate cancer based on magnetic resonance imaging/transrectal ultrasound fusion biopsy technique.

OBJECTIVE: To examine the effect of permanent salvage brachytherapy in prostate cancer patients suffering recurrence after three-dimensional conformal external beam radiotherapy. METHODS: The ultra-focal (target lesion alone), hemi-lobe (within a hemi-lobe) or focused whole-gland (focusing on the lesion, but extending into the whole gland) pattern was selected based on the Gleason score for the targeted biopsy, the numbers of positive cores in the targeted and systematic biopsies, and the locations of the positive cores. Novel dosimetry criteria derived from three-dimensional cancer mapping, which was based on targeted magnetic resonance imaging/transrectal ultrasound fusion biopsies, were used in these cases. RESULTS: Permanent salvage brachytherapy was carried out in 13 patients who suffered prostate-specific antigen failure (prostate-specific antigen 2.1-6.8 ng/mL; age range 57-75 years; Gleason score ≤7 [n = 10], Gleason score ≥8 [n = 2] and Gleason score not available [n = 1]) since 2012. The targeted biopsy showed a single focus in three patients. The ultra-focal, hemi-lobe and focused whole-gland patterns were chosen in three, five and five patients, respectively. During the follow-up period (median duration 48 months), prostate-specific antigen failure occurred in zero of three, one of five and three of five of the patients treated with the ultra-focal, hemi-lobe and focused whole-gland patterns, respectively. The 4-year biochemical recurrence-free survival rate was 74%. No grade 3-4 adverse intestinal or urological events occurred. CONCLUSIONS: Targeted fusion biopsy-based three-dimensional cancer mapping should be used for permanent salvage brachytherapy treatment planning to reduce the incidence of treatment-related adverse events while maintaining good oncological outcomes.

Characterization of spatial distribution of tumor-infiltrating CD8+ T cells refines their prognostic utility for pancreatic cancer survival.

The abundance of cytotoxic T-cell infiltrates has important implications for patient outcome and therapeutic design for pancreatic ductal adenocarcinoma. However, intratumoral heterogeneity remains a challenge to understanding the complex immune microenvironment. We hypothesized that characterizing CD8+ cell distribution within pancreatic adenocarcinoma tissues might refine the prognostic value of tumor-infiltrating CD8+ lymphocytes. Using multiplex immunohistochemistry-based image analysis on whole-tissue sections of 214 pancreatic ductal adenocarcinomas, we measured CD8+ cell densities in the tumor center, the tumor margin, and the whole tumor, along with the proximity of CD8+ cells to carcinoma cells. Multivariable Cox regression analysis was performed to assess the associations of CD8+ cell densities with pancreatic cancer-specific survival, adjusting for clinicopathologic and immune-related features, including tumor expressions of TP53, SMAD4, and the programmed cell death 1 ligand 1 (CD274, PD-L1) and the extent of tertiary lymphoid structures. There was substantial heterogeneity in CD8+ cell density, with the mean density in the tumor center less than half that in the tumor margin. Tumor CD274 expression and extensive tertiary lymphoid structures were appeared to be associated with higher CD8+ cell density in the tumor margin (P = 0.037 and P = 0.005, respectively), but not with that in the tumor center (P > 0.50). The association of higher CD8+ cell density with prolonged survival was significant for the whole tumor (Ptrend = 0.009); however, the association was stronger for the tumor center (Ptrend = 0.002) and insignificant for the tumor margin (Ptrend = 0.07). Tumor cell-CD8+ cell distance correlated strongly with CD8+ cell density, whereas the density of CD8+ cells proximate to cancer cells exhibited no prognostic association. In conclusion, spatial computational analysis on pancreatic ductal adenocarcinoma reveals the prognostic validity of CD8+ cell density in the tumor center, where CD8+ cell infiltration is ununiformly restricted, likely suggesting pro-tumorigenic roles of the immunosuppressive tumor microenvironment of pancreatic cancer.

Magnetic resonance imaging/transrectal ultrasound fusion-targeted prostate biopsy using three-dimensional ultrasound-based organ-tracking technology: Initial experience in Japan.

OBJECTIVE: To evaluate the impact of magnetic resonance imaging/transrectal ultrasound fusion-targeted prostate biopsy on the diagnosis of clinically significant prostate cancer using real-time three-dimensional ultrasound-based organ-tracking technology. METHODS: The present study was a retrospective review of 262 consecutive patients with prostate-specific antigen of 7.1 ng/mL (interquartile range 4.0-19.8). All patients received pre-biopsy magnetic resonance imaging and had a suspicious lesion for clinically significant prostate cancer. All patients underwent a combination of systematic biopsy (6 cores) and three-dimensional ultrasound-based magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (2 cores). The positive rate of any cancer, positive rate of clinically significant prostate cancer, Gleason score and maximum cancer core length were compared between systematic biopsy versus magnetic resonance imaging/transrectal ultrasound fusion-targeted prostate biopsy. RESULTS: Overall, the positive rate of any cancer per patient was 61% (160/262) in systematic biopsy versus 79% (207/262) in magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (P < 0.0001); and that of clinically significant prostate cancer per patient was 46% (120/262) in systematic biopsy versus 70% (181/262) in magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (P < 0.0001). The positive rate of any cancer per core was 21.7% (330/1523) in systematic biopsy versus 68.6% (406/592) in magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (P < 0.0001), and that of clinically significant prostate cancer per core was 12.7% (193/1423) in systematic biopsy versus 60.3% (357/592) in magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (P < 0.0001). Adding systematic biopsy leads to 13 more cancer cases (5%). The distribution of Gleason score (6/7/8/9/10) was 59/71/23/6/1 in systematic biopsy versus 48/105/36/15/2 in magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (P = 0.005). The maximum cancer core length was 5 mm (0.5-16) in systematic biopsy versus 8 mm (1-19 mm) in magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy (P < 0.0001). CONCLUSIONS: Three-dimensional ultrasound-based magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy seems to be associated with a higher detection rate of clinically significant prostate cancer, with fewer cores than systematic random biopsy. However, significant cancer can still be detected by the systematic technique only. A combination of systematic biopsy with the targeted biopsy technique would avoid the underdiagnosis of clinically significant prostate cancer.

CNPY2 promoted the proliferation of renal cell carcinoma cells and increased the expression of TP53.

Renal cell carcinoma (RCC) is the most common type of kidney cancer. However, the mechanisms underlying the progression of the disease are not well understood. The data in this report suggest that canopy FGF signaling regulator 2 (CNPY2) is a promoter of RCC progression. We found that CNPY2 significantly promoted growth of RCC cells and upregulated TP53 gene expression. Although TP53 is widely known as a tumor suppressor, in RCC TP53 promoted tumor cell growth. A typical p53 target gene, CDKN1A, was upregulated by both p53 and CNPY2 in RCC cells, suggesting that CNPY2 increased the expression level of TP53. Consistent with these results, CNPY2 and TP53 expression levels were positively correlated in RCC patients. These findings suggested that CNPY2 promoted cancer cell growth in RCC through regulating TP53 gene expression.

Long-term complete response of advanced hepatocellular carcinoma treated with multidisciplinary therapy including reduced dose of sorafenib: case report and review of the literature.

An 83-year-old man underwent computed tomography during a routine check-up due to a history of surgical treatment for pancreatic cancer. Two tumors were detected in the anterior segment of the liver. A needle biopsy of the larger tumor was performed, and pathological examination showed that the tumor was a poorly differentiated hepatocellular carcinoma. Resection was not performed considering the patient's poor physical condition. Thus, transcatheter arterial chemoembolization and radiofrequency ablation of the tumors were performed. Three months later, residual tumor of the larger lesion and multiple pulmonary metastases were detected. This time, continuous hepatic arterial infusion chemotherapy was performed. Although the pulmonary metastases markedly reduced, tumor thrombi appeared in the right portal vein on computed tomography. Finally, sorafenib was administered, which led to disappearance of the tumor thrombi and no other signs of recurrence 8 months after initiation of sorafenib on computed tomography. Although sorafenib administration has continued at reduced doses of 200 mg per day or less due to hypertension, complete response has persisted for the past 34 months. It is noteworthy that sorafenib has been given at reduced doses, but a long-term complete response is maintained in a patient who had portal tumor thrombi and distant metastasis. Herein, we present this rare case of advanced hepatocellular carcinoma controlled with reduced doses of sorafenib following multidisciplinary therapy, describe our single center experience with sorafenib use in patients with hepatocellular carcinoma, and review previous reports that focused on dose reduction of sorafenib.

OATP1B3 expression is strongly associated with Wnt/ß-catenin signalling and represents the transporter of gadoxetic acid in hepatocellular carcinoma.

BACKGROUND & AIMS: In the current era of emerging molecular targeted drugs, it is necessary to identify before treatment the specific subclass to which a tumour belongs. Gadoxetic acid is a liver-specific contrast agent that is preferentially taken up by hepatocytes. Therefore, gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) should provide precise molecular information about hepatocellular carcinomas (HCCs). The aim of this study was to investigate the transporters of gadoxetic acid in HCC comprehensively and to analyse the molecular regulatory mechanism of such transporters. METHODS: Expression levels of transporters, transcriptional factors and Wnt target genes in clinical samples were examined by quantitative real-time reverse transcription polymerase chain reaction and immunohistochemistry. LiCl treatment of the HCC cell line KYN-2 was conducted in vitro to assess the effects of Wnt signalling activity. RESULTS: Comprehensive analyses of transporter mRNAs and protein expressions revealed that the organic anion transporting polypeptide 1B3 (OATP1B3) had the strongest correlation with tumour enhancement in hepatobiliary-phase images of EOB-MRI. Association analysis with OATP1B3 expression revealed significant correlation with the expression of Wnt/ß-catenin target genes. Further, LiCl treatment induced OATP1B3 mRNA expression in KYN-2 cells, indicating a strong association between OATP1B3 expression and Wnt/ß-catenin signalling. The sensitivity and specificity to predict Wnt/ß-catenin-activated HCC using tumour enhancement in EOB-MRI were 78.9% and 81.7%, respectively. CONCLUSIONS: OATP1B3 was confirmed as the most important transporter mediating HCC enhancement in EOB-MRI. OATP1B3 expression showed a strong association with the expression of Wnt/ß-catenin target genes, therefore, OATP1B3-upregulated HCC likely represents a specific subclass of Wnt/ß-catenin-activated HCC.

A genetic screen in Drosophila for regulators of human prostate cancer progression.

To uncover the mechanism by which human prostate cancer progresses, we performed a genetic screen for regulators of human prostate cancer progression using the Drosophila accessory gland, a functional homolog of the mammalian prostate. Cell growth and migration of secondary cells in the adult male accessory gland were found to be regulated by paired, N-cadherin, and E-cadherin, which are Drosophila homologues of regulators of human prostate cancer progression. Using this screening system, we also identified three genes that promoted growth and migration of secondary cells in the accessory gland. The human homologues of these candidate genes - MRGBP, CNPY2, and MEP1A - were found to be expressed in human prostate cancer model cells and to promote replication and invasiveness in these cells. These findings suggest that the development of the Drosophila accessory gland and human prostate cancer cell growth and invasion are partly regulated through a common mechanism. The screening system using the Drosophila accessory gland can be a useful tool for uncovering the mechanisms of human prostate cancer progression.

Cystic tumor of the liver without ovarian-like stroma or bile duct communication: two case reports and a review of the literature.

We report two cases of cystic neoplasm of the liver with mucinous epithelium in which both ovarian-like stroma and bile duct communication were absent. The first case was a 41-year-old woman. She underwent right trisegmentectomy due to a multilocular cystic lesion, 15 cm in diameter, with papillary nodular components in the medial segment and right lobe. Histologically, arborizing papillae were seen in the papillary lesion. The constituent neoplastic cells had sufficient cytoarchitectural atypia to be classified as high-grade dysplasia. The second case was a 60-year-old woman. She underwent left lobectomy due to a unilocular cystic lesion, 17 cm in diameter, in the left lobe. Histologically, the cyst wall was lined by low columnar epithelia with slight cellular atypia. In both cases, neither ovarian-like stroma nor bile duct communications were found throughout the resected specimen. According to the most recent World Health Organization (WHO) classification in 2010, cystic tumors of the liver with mucinous epithelium are classified as mucinous cystic neoplasms when ovarian-like stromata are found, and as intraductal papillary neoplasm of bile duct when bile duct communication exists. Therefore, we diagnosed the cystic tumors as 'biliary cystadenoma' according to the past WHO classification scheme from 2000. We believe that the combined absence of both ovarian-like stroma and bile duct communication is possible in mucinous cystic tumors of the liver. Herein, we have described the clinicopathologic features of the two cases and reviewed past cases in the literature.

[A pediatric wilms' tumor presenting with a right renal injury].

We report a case of a pediatric Wilms' tumor presenting after a right renal injury. A 6-year-old girl presented to a nearby hospital with right back pain after a fall. An abdominal computed tomography (CT) scan revealed a right renal injury with active hemorrhaging. She was then referred to our hospital. There another CT scan and a magnetic resonance imaging (MRI) scan revealed the disappearance of the active hemorrhaging but also the presence of a large renal tumor. We performed a right nephrectomy. The renal tumor was diagnosed as a nephroblastoma. Considering dissemination by trauma, chemotherapy and radiation therapy were performed.