Practice guidelines for managing extrahepatic biliary tract cancers.

Backgrounds/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions: The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Loss of Krüppel-like factor-10 facilitates the development of chemical-induced liver cancer in mice.

BACKGROUND: Krüppel-like factor 10 (KLF10) is involved in a positive feedback loop that regulates transforming growth factor ß (TGFß) signaling, and TGFß plays an important role in the pathogenesis of liver disease. Here, we investigated whether KLF10 deletion affects the development of liver fibrosis and hepatocellular carcinoma (HCC). METHODS: We induced KLF10 deletion in C57BL/6 mice. Liver fibrosis was induced by feeding a diet high in fat and sucrose (high-fat diet [HFD]), whereas HCC was produced by intraperitoneal administration of N-diethylnitrosamine (DEN). An in vitro experiment was performed to evaluate the role of KLF10 in the cancer microenvironment using Hep3B and LX2 cells. An immunohistochemical study of KLF10 expression was performed using human HCC samples from 60 patients who had undergone liver resection. RESULTS: KLF10 deletion resulted in an increased DEN-induced HCC burden with significant upregulation of SMAD2, although loss of KLF10 did not alter HFD-induced liver fibrosis. DEN-treated mice with KLF10 deletion exhibited increased levels of mesenchymal markers (N-cadherin and SNAI2) and tumor metastasis markers (matrix metalloproteinases 2 and 9). KLF10 depletion in Hep3B and LX2 cells using siRNA was associated with increased invasiveness. Compared with co-culture of KLF10-preserved Hep3B cells and KLF10-intact LX2 cells, co-culture of KLF10-preserved Hep3B cells and KLF10-depleted LX2 cells resulted in significantly enhanced invasion. Low KLF10 expression in resected human HCC specimens was associated with poor survival. CONCLUSION: The results of this study suggest that loss of KLF10 facilitates liver cancer development with alteration in TGFß signaling.

Prediction of Prognosis in Pancreatic Cancer According to Methionyl-tRNA Synthetase 1 Expression as Determined by Immunohistochemical Staining.

The serum level of CA 19-9 is a prognostic marker for pancreatic ductal adenocarcinoma (PDAC). We evaluated the ability of the expression level of methionyl-tRNA synthetase 1 (MARS1)-which facilitates cancer growth by modulating protein synthesis and the cell cycle-to predict the prognosis of PDAC. Immunohistochemical (IHC) staining was performed on pancreatic specimens obtained from patients with PDAC who were undergoing surgery. High MARS1 expression was defined as equal to, or greater than, that in normal acinar cells. Low MARS1 expression was defined as weaker than in normal acinar cells, and stronger than in the pancreatic duct epithelium. Univariate and multivariate analyses were performed on other factors related to prognosis. Among 137 PDAC patients, no significant differences in baseline characteristics were found between those with high (n = 82) and low (n = 55) MARS1 expression. The median overall survival time of patients with high MARS1 expression was shorter than that of those with low expression (15.2 versus 17.2 months, log-rank test p = 0.044). The median disease-free survival (DFS) was not significantly different between the two groups. However, the DFS was shorter in patients with high than in those with low MARS1 expression (8.9 versus 11.2 months, log-rank test p = 0.067). In a multivariate analysis, lymph node metastasis and high MARS1 expression were associated with a poor prognosis of PDAC. Elevated MARS1 expression detected by IHC staining is associated with a poor prognosis of PDAC, suggesting that MARS1 has potential as a prognostic marker.

Comparison of Programmed Cell Death Ligand 1 Status between Core Needle Biopsy and Surgical Specimens of Triple-Negative Breast Cancer.

PURPOSE: Pembrolizumab is currently used to treat advanced triple-negative breast cancer (TNBC) and high-risk early TNBC with neoadjuvant chemotherapy (NAC). The tumor-infiltrating lymphocyte (TIL) level and programmed cell death ligand 1 (PD-L1) status are predictors of response to NAC and immune checkpoint inhibitor treatment. We aimed to investigate whether the PD-L1 status in core needle biopsies (CNBs) could represent the whole tumor in TNBC. MATERIALS AND METHODS: A total of 49 patients diagnosed with TNBC who received upfront surgery without NAC between January 2018 and March 2021 were included. The PD-L1 expression (SP142 and 22C3 clones) and TIL were evaluated in paired CNBs and resected specimens. The concordance PD-L1 status and TIL levels between CNBs and resected specimens were analyzed. RESULTS: PD-L1 positivity was more frequently observed in resected specimens. The overall reliability of TIL level in the CNB was good [intraclass correlation coefficient (ICC)=0.847, p<0.001]. The agreements of PD-L1 status were good and fair, respectively (SP142, κ=0.503, p<0.001; 22C3, κ=0.380, p=0.010). As the core number of CNB increased, the reliability and agreement also improved, especially from five tumor cores (TIL, ICC=0.911, p<0.001; PD-L1 [22C3], κ=0.750, p=0.028). Regarding PD-L1 (SP142), no further improvement was observed with ≥5 tumor cores (κ=0.600, p=0.058). CONCLUSION: CNBs with ≥5 tumor cores were sufficient to represent the TIL level and PD-L1 (22C3) status in TNBC.

Retrospective analysis of 8th edition American Joint Cancer Classification: Distal cholangiocarcinoma.

Backgrounds/Aims: This is a retrospective analysis of whether the 8th edition American Joint Committee on Cancer (AJCC) was a significant improvement over the 7th AJCC distal extrahepatic cholangiocarcinoma classification. Methods: In total, 111 patients who underwent curative resection of mid-distal bile duct cancer from 2002 to 2019 were included. Cases were re-classified into 7th and 8th AJCC as well as clinicopathological univariate and multivariate, and Kaplan-Meier survival curve and log rank were calculated using R software. Results: In patient characteristics, pancreaticoduodenectomy/pylorus preserving pancreaticoduodenectomy had better survival than segmental resection. Only lymphovascular invasion was found to be significant (hazard ratio 2.01, p = 0.039) among all clinicopathological variables. The 8th edition AJCC Kaplan Meier survival curve showed an inability to properly segregate stage I and IIA, while there was a large difference in survival probability between IIA and IIB. Conclusions: The 8th distal AJCC classification did resolve the anatomical issue with the T stage, as T1 and T3 showed improvement over the 7th AJCC, and the N stage division of the N1 and N2 category was found to be justified, with poorer survival in N2 than N1. Meanwhile, in TMN staging, the 8th AJCC was able differentiate between early stage (I and IIA) and late stage (IIB and III) to better explain the patient prognosis.

Diagnostic Accuracy of Vitreous Cytology in Patients with Vitreoretinal Lymphoma.

(1) Background: To determine the diagnostic value of vitreous cytology in patients with vitreoretinal lymphoma (VRL) and evaluate its diagnostic accuracy relative to that of other diagnostic tests. (2) Methods: In total, 38 eyes from 38 patients with VRL who underwent diagnostic vitrectomy and were followed up for at least 6 months were analyzed. The clinical manifestations and VRL diagnostic rates for all diagnostic tests were determined. (3) Results: The presence of vitreous cells/opacity was the most common ophthalmic finding (97.4%), followed by sub-retinal pigment epithelial infiltration (65.8%) and retinal hemorrhage (21.1%). The VRL diagnostic rates were 89.3% for interleukin (IL)-10 levels > 50 pg/mL; 82.1% for IL-10/IL-6 ratios > 1; 60.0% and 63.3% for immunoglobulin heavy chain and kappa light chain clonality assays, respectively; and 44.4% for vitreous cytology. The VRL diagnostic rate for vitreous cytology was significantly lower in the steroid pretreatment group than in the non-steroid pretreatment group (p = 0.007). (4) Conclusions: The VRL detection rate for vitreous cytology was lower than that for the other tests, especially in patients who received steroid pretreatment. These findings suggest that even if vitreous cytology findings are negative, other tests and characteristic fundus findings should be evaluated to confirm VRL diagnosis.

Benign multicystic mesothelioma of appendiceal origin treated by hyperthermic intraperitoneal chemotherapy: A case report.

INTRODUCTION AND IMPORTANCE: Peritoneal benign cystic mesothelioma is a rare benign tumor that originates from a mesothelial proliferative lesion of the peritoneum. However, proper surgical management remains unclear due to its low incidence. We report a clinical case of peritoneal benign cystic mesothelioma treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC). CASE PRESENTATION: A 60-year-old female who underwent laparoscopic appendectomy in 2015 presented with abdominal pain in right lower quadrant area. Computed tomography of the abdomen and pelvis revealed a ruptured appendiceal mucocele or mucinous neoplasm, and several seeding-like small nodules in the greater omentum and right peritoneum. Cytoreductive surgery followed by HIPEC was performed; right hemicolectomy and lymph node dissection, omentectomy, and right abdominal partial peritonectomy. HIPEC with mitomycin was conducted for 90 min and an anastomosis between the ileum and colon was made after HIPEC. The pathologic results revealed the colonic mass was a multi-loculated cyst lined by mesothelial cells containing amorphous eosinophilic fibrinoid material, which are common features of benign cystic mesothelioma. CLINICAL DISCUSSION: Peritoneal benign cystic mesothelioma is known as a borderline disease of mesothelial tumors. Because its etiology is unknown, treatment strategies are not determined. CONCLUSION: Cytoreductive surgery followed by HIPEC can be considered to treat peritoneal benign cystic mesothelioma and prevent its malignant transformation.

SFRP4 and CDX1 Are Predictive Genes for Extragastric Recurrence of Early Gastric Cancer after Curative Resection.

Extragastric recurrence of early gastric cancer (EGC) after curative resection is rare, but prognosis has been poor in previous reports. Recently, single patient classifier (SPC) genes, such as secreted frizzled-related protein 4 (SFRP4) and caudal-type homeobox 1 (CDX1), were associated with prognosis and chemotherapy response in stage II-III gastric cancer. The aim of our study is, therefore, to elucidate predictive factors for extragastric recurrence of EGC after curative resection, including with the expression of SPC genes. We retrospectively reviewed electronic medical records of 1974 patients who underwent endoscopic or surgical curative resection for EGC. We analyzed clinicopathological characteristics to determine predictive factors for extragastric recurrence. Total RNA was extracted from formalin-fixed, paraffin-embedded (FFPE) tumor tissue and amplified by real-time reverse transcription polymerase chain reaction to evaluate expression of SPC genes. Overall incidences of extragastric recurrence were 0.9%. In multivariate analysis, submucosal invasion (odds ratio [OR] = 6.351, p = 0.032) and N3 staging (OR = 171.512, p = 0.012) were independent predictive factors for extragastric recurrence. Mean expression of SFRP4 in extragastric recurrence (-2.8 ± 1.3) was significantly higher than in the control group (-4.3 ± 1.6) (p = 0.047). Moreover, mean expression of CDX1 in extragastric recurrence (-4.6 ± 2.0) was significantly lower than in the control group (-2.4 ± 1.8) (p = 0.025). Submucosal invasion and metastasis of more than seven lymph nodes were independent predictive factors for extragastric recurrence. In addition, SFRP4 and CDX1 may be novel predictive markers for extragastric recurrence of EGC after curative resection.

The dual role of transforming growth factor-beta signatures in human B viral multistep hepatocarcinogenesis: early and late responsive genes.

Background/Aim: Transforming growth factor-beta (TGF-ß) has a dichotomous role, functioning as a tumor suppressor and tumor promoter. TGF-ß signatures, explored in mouse hepatocytes, have been reported to predict the clinical outcomes of hepatocellular carcinoma (HCC) patients; HCCs exhibiting early TGF-ß signatures showed a better prognosis than those with late TGF-ß signatures. The expression status of early and late TGF-ß signatures remains unclear in defined lesions of human B-viral multistep hepatocarcinogenesis. Methods: The expression of TGF-ß signatures, early and late responsive signatures of TGF-ß were investigated and analyzed for their correlation in cirrhosis, low-grade dysplastic nodules (DNs), high-grade DNs, early HCCs and progressed HCCs (pHCCs) by real-time PCR and immunohistochemistry. Results: The expression levels of TGF-ß signaling genes (TGFB1, TGFBR1, TGFBR2 and SMAD4) gradually increased with the progression of hepatocarcinogenesis, peaking in pHCCs. The expression of early responsive genes of TGF-ß (GADD45B, FBP1, CYP1A2 and CYP3A4) gradually decreased, and that of the late TGF-ß signatures (TWIST and SNAI1) significantly increased according to the progression of multistep hepatocarcinogenesis. Furthermore, mRNA levels of TWIST and SNAI1 were well correlated with those of stemness markers, with upregulation of TGF-ß signaling, whereas FBP1 expression was inversely correlated with that of stemness markers. Conclusions: The enrichment of the late responsive signatures of TGF-ß with induction of stemness is considered to be involved in the progression of the late stage of multistep hepatocarcinogenesis, whereas the early responsive signatures of TGF-ß are suggested to have tumor-suppressive roles in precancerous lesions of the early stage of multistep hepatocarcinogenesis.

Association between pancreatic fibrosis and development of pancreoprivic diabetes after pancreaticoduodenectomy.

This study investigated the correlation between pancreatic fibrosis (PF) and development of pancreoprivic diabetes after pancreaticoduodenectomy (PD). Ninety-five patients who underwent PD at Gangnam Severance Hospital between 2014 and 2017 were enrolled. PF grade was evaluated with alpha-smooth muscle actin (SMA) and Masson's trichrome (TRC) staining. New-onset pancreoprivic diabetes and recurrence of disease were evaluated using fasting blood glucose measurement and radiography taken at 3-month intervals. Sixty-one patients did not have preoperative diabetes, however, 40 (65.6%) patients developed pancreoprivic diabetes after PD. High-grade PF was more common in the diabetes group than in the normal group (SMA, 42.5% vs. 28.6%, P = 0.747; TRC, 47.5% vs. 28.6%, P = 0.361). The 1-year cumulative incidence of hyperglycemia/pancreoprivic diabetes was higher with high-grade PF than low-grade PF (SMA, 94.4% vs. 73.0%, P = 0.027; TRC, 89.3% vs. 75.0%, P = 0.074). The SMA-TRC combined high-grade group had a higher proportion of primary pancreatic disease than the combined low-grade group (90.0% vs. 37.5%, P = 0.001). The 5-year disease-free survival of patients with pancreatic cancer was worse with high-grade PF than low-grade PF (SMA, 24.5% vs. 66.3%, P = 0.026; TRC, 23.6% vs. 58.4%, P = 0.047). In conclusion, patients with severe PF are more likely to develop pancreoprivic diabetes after PD and have worse disease-free survival.

[Up-to-date Knowledge on the Pathological Diagnosis of Hepatocellular Carcinoma].

Hepatocellular carcinoma (HCC) has heterogeneous molecular and pathological features and biological behavior. Large-scale genetic studies of HCC were accumulated, and a pathological-molecular classification of HCC was proposed. Approximately 35% of HCCs can be classified into distinct histopathological subtypes according to their molecular characteristics. Among recently identified subtypes, macrotrabecular massive HCC, neutrophil-rich HCC, vessels encapsulating tumor clusters HCC, and progenitor phenotype HCC (HCC with CK19 expression) are associated with a poor prognosis, whereas the lymphocyte-rich HCC subtype is related to a better prognosis. This review provides up-to-date knowledge on the pathological diagnosis of HCC according to the updated World Health Organization Classification of Digestive System Tumors 5th ed.

Methionyl-tRNA synthetase and aminoacyl-tRNA synthetases interacting multi-functional protein-lacking exon 2 as potential diagnostic biomarkers for lung cancer.

Cytological specimens from computed tomography (CT)-guided needle aspiration biopsy (CT-NAB) have relatively low sensitivity for lung cancer diagnosis. This study evaluated the usefulness of the dual immunofluorescence (IF) staining method using methionyl-tRNA synthetase (MARS), aminoacyl-tRNA synthetases interacting multi-functional protein-lacking exon 2 (AIMP2-DX2), and pan-cytokeratin (pan-CK) obtained from clinical specimens. One-hundred forty-five cytology specimens were prospectively collected from patients who underwent CT-NAB under the suspicion of lung cancer. The results of two combinations of MARS, AIMP2-DX2, and pan-CK dual IF staining were compared with those of conventional cytology by calculating the area under the curve (AUC). The results of combining dual IF with conventional cytology showed higher AUC than conventional cytology alone: cytology/MARS/AIMP2-DX2 (0.891 vs. 0.829, P = 0.003), cytology/MARS/pan-CK (0.916 vs. 0.829, P < 0.001), and cytology/AIMP2-DX2/pan-CK (0.877 vs. 0.829, P = 0.005). In specimens with non-diagnostic results in conventional cytology, MARS/AIMP2-DX2 dual IF staining showed sensitivity, specificity, and AUC of 60.0%, 86.4%, and 0.79, respectively. The dual IF staining method using two combinations of MARS, AIMP2-DX2, and pan-CK is an effective diagnostic tool that can improve the lung cancer diagnostic yield by complementing conventional cytology.

Clinical utility of methionyl-tRNA synthetase 1 immunostaining in cytologic brushings of indeterminate biliary strictures: a multicenter prospective study.

BACKGROUND AND AIMS: Endobiliary brushings are routinely used in the diagnosis, treatment, and prognostication of biliary strictures. However, standard Papanicolaou (Pap) staining has a low sensitivity in this setting, and the accuracy of brush cytology has not been established for indeterminate strictures. We therefore evaluated the diagnostic merit of methionyl-transfer RNA synthetase 1 (MARS1) immunofluorescence (IF) staining in such cytologic specimens. METHODS: During ERCP, endobiliary brushings were obtained from patients with extrahepatic biliary strictures prospectively enrolled at 6 tertiary hospitals. Using liquid-based cytologic preparations of these samples, we performed Pap and MARS1 IF staining. RESULTS: In total, 240 patients were eligible; of these, we compared the Pap and MARS1 IF staining results of 218 (malignant, 157; benign, 61). By conventional Pap staining, the diagnoses were distributed as follows: malignant, 55; suspicious of malignancy, 60; atypical, 45; negative for malignancy, 58. MARS1 IF staining was strongly positive in malignant biliary stricture but not so in specimens negative for malignancy. The diagnostic parameters (sensitivity, specificity, positive predictive value, negative predictive value, and accuracy) of the MARS1 IF (93.6%, 96.7%, 98.7%, 85.5%, and 94.5%, respectively) and conventional Pap (73.2%, 100%, 100%, 59.2%, and 80.7%, respectively) staining methods differed significantly (P < .0001). CONCLUSIONS: The high sensitivity and accuracy of MARS1 IF staining enabled the detection of malignancy in patients with biliary strictures. Further prospective studies are needed to validate our findings. (Clinical trial registration number: NCT03708445.).

Pathological predictive factors for late recurrence of hepatocellular carcinoma in chronic liver disease.

BACKGROUND & AIMS: Late recurrence of hepatocellular carcinoma (HCC) is regarded as de novo HCC from chronic hepatitis. This study investigated clinicopathological and molecular factors to develop a nomogram for predicting late HCC recurrence (>2 years after curative resection). METHODS: The training and validation cohorts included HCC patients with a major aetiology of hepatitis B who underwent curative resection. Clinicopathological features including lobular and porto-periportal inflammatory activity, fibrosis and liver cell change were evaluated. Proteins encoded by genes related to late recurrence were identified using a reverse phase protein array of 95 non-tumourous liver tissues. Immunoexpression of phosphorylated signal transducer and activator of transcription 3 (pSTAT3), plasminogen activator inhibitor-1, phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) and spleen tyrosine kinase (SYK) was measured. RESULTS: Late recurrence occurred in 74/402 (18%) and 47/243 (19%) in the training and validation cohorts respectively. Cirrhosis, moderate/severe lobular inflammatory activity, and expression of pSTAT3, pERK1/2, and SYK proteins correlated to the gene signature of hepatocyte injury and regeneration were independently associated with late recurrence, with odds ratios (95% confidence intervals) of 2.0 (1.2-3.3), 21.1 (4.3-102.7) and 6.0 (2.1-17.7) respectively (P < .05 for all). A nomogram based on these variables (histological parameters and immunohistochemical marker combinations) showed high reliability in both the training and validation cohorts (Harrell's C index: 0.701 and 0.716; 95% confidence intervals: 0.64-0.76 and 0.64-0.79 respectively). CONCLUSIONS: The combination of pSTAT3, pERK1/2 and SYK immunoexpression with high lobular inflammatory activity and cirrhosis (fibrosis) predicts late HCC recurrence.

Gadoxetic acid-enhanced MRI of macrotrabecular-massive hepatocellular carcinoma and its prognostic implications.

BACKGROUND & AIMS: Despite the clinical and genetic significance of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC), its characteristics on imaging have not been described. This study aimed to characterise MTM-HCC on gadoxetic acid-enhanced MRI and to evaluate the diagnostic accuracy and prognostic value of these imaging characteristics. METHODS: We enrolled 3 independent cohorts from 2 tertiary care centres. The 3 cohorts consisted of a total of 476 patients who underwent gadoxetic acid-enhanced MRI and surgical resection for treatment-naïve single HCCs. Independent review of histopathology and MRI by 2 reviewers was performed for each cohort, and inter-reader agreement was evaluated. Based on the result of MRI review in the training cohort (cohort 1), we developed 2 diagnostic criteria for MTM-HCC and evaluated their prognostic significance. The diagnostic performance and prognostic significance were validated in 2 validation cohorts (cohorts 2 and 3). RESULTS: We developed 2 diagnostic MRI criteria (MRIC) for MTM-HCC: MRIC-1, ≥20% arterial phase hypovascular component; MRIC-2, ≥50% hypovascular component and 2 or more ancillary findings (intratumoural artery, arterial phase peritumoural enhancement, and non-smooth tumour margin). MRIC-1 showed high sensitivity and negative predictive value (88% and 95% in the training cohort, and 88% and 97% in the pooled validation cohorts, respectively), whereas MRIC-2 demonstrated moderate sensitivity and high specificity (47% and 94% in the training cohort, and 46% and 96% in the pooled validation cohorts, respectively). MRIC-2 was an independent poor prognostic factor for overall survival in both training and pooled validation cohorts. CONCLUSIONS: Using gadoxetic acid-enhanced MRI findings, including an arterial phase hypovascular component, we could stratify the probability of MTM-HCC and non-invasively obtain prognostic information. LAY SUMMARY: Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a histopathologic subtype of HCC characterised by aggressive biological behaviour and poor prognosis. We developed imaging criteria based on liver MRI that could be used for the non-invasive diagnosis of MTM-HCC. HCCs showing imaging findings of MTM-HCC were associated with poor outcomes after hepatic resection.

The Clinicopathological and Prognostic Significance of Nrf2 and Keap1 Expression in Hepatocellular Carcinoma.

Nuclear factor E2-related factor2 (Nrf2) activation is associated with both cytoprotective effects and malignant behavior of cancer cells. This study aimed to evaluate the clinicopathological implications of the expression of Nrf2, pNrf2, and its regulator Keap1 in human hepatocellular carcinomas (HCCs). Tissue microarrays consisting of 285 surgically resected HCCs were immunohistochemically stained with pNrf2, Nrf2, Keap1, stemness-related markers (keratin 19 (K19), epithelial cell adhesion molecule (EpCAM)), carbonic anhydrase IX (CAIX), epithelial-mesenchymal transition (EMT)-related markers (ezrin, uPAR, E-cadherin), and p53, and the results were correlated with the clinicopathological features. pNrf2 expression was significantly associated with increased proliferative activity, as well as EpCAM, ezrin, p53, and CAIX expression and E-cadherin loss (p < 0.05, all). Strong cytoplasmic Nrf2 expression was associated with CAIX and ezrin expression (p < 0.05, both). Keap1 was associated with increased proliferative activity, portal vein invasion, EMT-related markers, and p53 expression in CAIX-negative HCCs (p < 0.05, all). Both pNrf2 and cytoplasmic Nrf2 expression were associated with decreased overall survival (p < 0.05, both), and cytoplasmic Nrf2 expression was an independent predictor of decreased overall survival on multivariate analysis (hazard ratio 4.15, p < 0.001). Both pNrf2 and cytoplasmic Nrf2 expression were associated with poor survival and aggressive behavior of HCC. In addition, Keap1 expression was also associated with aggressive HCC behavior in CAIX-negative HCCs, suggesting that Keap1 expression should be interpreted in the context of hypoxia status.

Forkhead Box C1 (FOXC1) Expression in Stromal Cells within the Microenvironment of T and NK Cell Lymphomas: Association with Tumor Dormancy and Activation.

PURPOSE: Forkhead box C1 (FOXC1) is critical for maintaining bone marrow microenvironments during hematopoiesis, but its role in hematological malignancies remains obscure. Here, we investigated whether FOXC1 regulates tumor dormancy and activation in the microenvironments of T and natural killer (NK) cell lymphomas. MATERIALS AND METHODS: One hundred and twenty cases of T and NK cell lymphomas were included; the immunohistochemical expression of FOXC1 was investigated in stromal cells, and numbers of FOXC1+ stromal cells were counted. Furthermore, the expression of phosphorylated p38 (p-p38) and phosphorylated ERK1/2 (p-ERK1/2) in tumor cells was investigated using immunohistochemistry. RESULTS: FOXC1 was variably expressed in C-X-C motif chemokine 12-associated reticular stromal cells, histiocytes, (myo)fibroblasts, and endothelial cells. The phenotypes of cases were categorized as dormant (high p-p38/low p-ERK1/2; n=30, 25.0%), active (high p-ERK1/2/low p-p38; n=25, 20.8%), or intermediate (others; n=65, 54.2%). Lower FOXC1+ stromal cell infiltration was associated with the dormant phenotype, the precursor T lymphoblastic leukemia/lymphoma subtype, and inferior overall survival rates, whereas higher FOXC1+ stromal cell infiltration was associated with the active phenotype and favorable patient prognosis (p < 0.05 for all). CONCLUSION: These results suggested that FOXC1+ stromal cells within the microenvironments of T and NK cell lymphomas might be related to tumor phenotypes.

WWC1 and NF2 Prevent the Development of Intrahepatic Cholangiocarcinoma by Regulating YAP/TAZ Activity through LATS in Mice.

Hippo signaling acts as a tumor suppressor pathway by inhibiting the proliferation of adult stem cells and progenitor cells in various organs. Liver-specific deletion of Hippo pathway components in mice induces liver cancer development through activation of the transcriptional coactivators, YAP and TAZ, which exhibit nuclear enrichment and are activated in numerous types of cancer. The upstream-most regulators of Warts, the Drosophila ortholog of mammalian LATS1/2, are Kibra, Expanded, and Merlin. However, the roles of the corresponding mammalian orthologs, WWC1, FRMD6 and NF2, in the regulation of LATS1/2 activity and liver tumorigenesis in vivo are not fully understood. Here, we show that deletion of both Wwc1 and Nf2 in the liver accelerates intrahepatic cholangiocarcinoma (iCCA) development through activation of YAP/TAZ. Additionally, biliary epithelial cell-specific deletion of both Lats1 and Lats2 using a Sox9-CreERT2 system resulted in iCCA development through hyperactivation of YAP/TAZ. These findings suggest that WWC1 and NF2 cooperate to promote suppression of cholangiocarcinoma development by inhibiting the oncogenic activity of YAP/TAZ via LATS1/2.

Gross type of hepatocellular carcinoma reflects the tumor hypoxia, fibrosis, and stemness-related marker expression.

BACKGROUND: Hepatocellular carcinoma (HCC) is subclassified into five gross types, namely, vaguely nodular (VN), single nodular (SN), single nodular with extranodular growth (SNEG), confluent multinodular (CM), and infiltrative (INF) type. However, the pathological background underlying differences in biological behavior of different gross types of HCC remains unclear. METHODS: The histopathological features, clinical outcomes of HCC gross types, and their relationships with stemness-related marker status and fibrotic/hypoxic tumor microenvironment (TME) were evaluated in 266 resected HCCs. The stemness-related markers (CD24, CD44, CD133, SALL4, YAP1, K19 and EpCAM), fibrous tumor stroma (αSMA), and hypoxia (CAIX) were evaluated with immunohistochemistry. RESULTS: Poorer differentiation, reduced capsule formation, higher microvascular invasion, larger tumor size and larger area of necrosis were observed in order of VN-SN-SNEG-CM-INF type (p = 0.005 for all, linear-by-linear association). The expression of summed stemness-related markers and hypoxic/fibrotic TME showed an increasing trend in order of VN-SN-SNEG-CM-INF type (p < 0.005), and their expression well correlated with each other. INF type was found only in HCCs with hypoxic/fibrotic TME or high expression of stemness-related markers. CAIX expression and tumor necrosis ≥ 30% were independent prognostic markers for disease-specific survival. Early recurrence-free survival showed a significant difference based on gross types, revealing best outcome with VN type and worst outcome with INF type. CONCLUSION: The marker expression of stemness-related and hypoxic/fibrotic TME of HCC showed an increasing trend in order of VN-SN-SNEG-CM-INF gross types, and their cross-talk may be involved in the determination of various gross-morphological features and their distinct biological behavior.

Clinicopathological characteristics of intrahepatic cholangiocarcinoma according to gross morphologic type: cholangiolocellular differentiation traits and inflammation- and proliferation-phenotypes.

BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) is subclassified into mass-forming (MF), periductal-infiltrative (PI), and mixed types grossly; however, their clinicopathological significance remains controversial. METHODS: Clinicopathological characteristics of iCCA gross types were analysed according to histopathological type (small-duct, large-duct, indeterminate) or cholangiolocellular differentiation trait (CDT) in 108 iCCAs. The expression levels of inflammation-marker (CRP, FGB) and proliferation-marker (phospho-ERK1/2, Ki-67) were evaluated by immunohistochemistry. RESULTS: There were 87 MF, 8 PI, and 13 mixed-gross type. Small-duct-type (39, 44.8%) and CDT (19, 21.8%) were found only in MF-gross type. The inflammation-marker expression was higher in MF-type than in PI- and mixed-gross types (P = 0.023). It was high in small-duct-type, middle in indeterminate-type, and low in large-duct-type (P = 0.015), and iCCAs with CDT showed higher inflammation-marker expression compared to those without (P < 0.001). Proliferation-marker expression did not differ according to gross type; however it was lower in iCCA with CDT compared to those without (P = 0.004). Subgrouping of the gross type according to histopathological type or CDT revealed that MF-type with small-duct-type or CDT had better overall survival compared to the others (P < 0.05). CONCLUSION: MF-type iCCA is more heterogeneous than other gross types. High inflammation-marker/low proliferation-marker expression in MF-type with CDT or small-duct-type may be related to a good outcome.