Immunophenotypes and Tumor Immune Microenvironment in Hepatocellular Carcinoma With Macrotrabecular Massive and Vessels Encapsulating Tumor Clusters.

BACKGROUND/AIM: Recently, vessels encapsulating tumor clusters (VETC) pattern and macrotrabecular massive (MTM) pattern of hepatocellular carcinoma (HCC) have been reported as aggressive histological types. These histological patterns showed an immunosuppressive tumor immune microenvironment (TIME). Since there have been no reports on the differences of these two subtypes simultaneously, this study examined the immunophenotypes and TIME of MTM-HCC and VETC-HCC immunohistochemically. PATIENTS AND METHODS: Seventy-four cases of previously diagnosed HCC, including 32 MTM-HCCs, 21 VETC-HCCs, and 21 conventional HCCs, were enrolled in immunohistochemical analysis. We conducted immunohistochemical analysis. RESULTS: We found that MTM-HCC showed less frequent expression of HepPar-1, which is one of the most common hepatocytic markers. In MTM-HCC, the frequency of high expression levels of Keratin19, carbonic anhydrase (CA) IX, and PD-L1 was higher compared to VETC-HCC and conventional HCC. PD-L1 expression was found in 34.4% of MTM-HCC, 0% of VETC-HCC, and 19.0% of conventional HCC. The rate of PD-L1 expression in MTM-HCC was significantly higher than the others (p=0.0015). PD-L1 expression was significantly associated with epithelial cell adhesion molecules and CA IX expression, which are representative markers of tumor stemness and hypoxic conditions, respectively. The CD8 infiltration in VETC-HCC was significantly lower than that in conventional HCC. CONCLUSION: MTM-HCC had different immunophenotypes and TIMEs compared to HCC with the VETC pattern. Although both had immunosuppressive TIME, the elements forming TIME were quite different. To enhance the immune checkpoint inhibitor efficacy, changing TIME from a suppressive to an active form is essential.

Electronic substituent effect on the conformation of a phenylalanine-incorporated cyclic peptide.

The Phe-incorporated cyclic peptide [cyclo(-Phe1-oxazoline2-d-Val3-thiazole4-Ile5-oxazoline6-d-Val7-thiazole8-)] is in a conformational equilibrium between square and folded forms in solution. In the folded form, a CH⋯π interaction between the Phe1 aromatic ring and the Oxz2 methyl group is observed. We endeavored to control the local conformation and thus modulate the CH⋯π interaction and flexibility of the Phe1 side chain by controlling the electronic substituent effects at the 4-position of the aromatic ring of the Phe1 residue. The effect of the 4-substituent on the global conformation was indicated by the linear relationship between the conformational free energies (ΔGo) determined through NMR-based quantification and the Hammett constants (σ). Electron-donating substituents, which had relatively strong CH⋯π interactions, promoted peptide folding by restraining the loss in entropy. Local control by the 4-substituent effects suggested that the Phe side chain exerts an entropic influence on the folding of these cyclic peptides.

Clinicopathological characteristics and molecular analysis of lymphocyte-rich hepatocellular carcinoma.

Lymphocyte-rich hepatocellular carcinoma (LR-HCC), a newly proposed subtype of HCC, is characterized with abundant lymphocyte infiltration in the tumor. LR-HCC has a relatively good prognosis and is quite rare (<1% of all HCC). We examined LR-HCC clinicopathological and molecular characteristics by analyzing 451 surgically resected HCC cases without any prior treatment history at our hospital between 2012 and 2021. Clinicopathological features of LR-HCC and other HCCs (non-LR-HCC) were compared. Neoplastic and nonneoplastic hepatocytes from LR-HCC (n = 4) were collected with a laser microdissection system; RNA was extracted, followed by microarray analysis to examine lymphocytic infiltration-related molecular targets. Immunohistochemical staining of identified molecular target was performed in LR-HCC and non-LR-HCC. CD3, CD20, and CD8 immunostaining was also performed in LR-HCCs. There were 28 cases of LR-HCC (6%). No statistically significant differences were found in clinicopathological features, except for gross type, between LR-HCC and non-LR-HCC cases. The LR-HCC 5-year survival rate was >90%. Microarray analysis revealed high CCL20 expression in LR-HCC cases; immunohistochemical study showed significantly higher CCL20 expression in LR-HCC (P < 0.01) than in non-LR-HCC. CCR6, the only CCL20 receptor, was observed in infiltrating lymphocytes and HCC cells in LR-HCC. There were significantly more CD3-positive cells than CD20-positive cells (P < 0.0001) in tumor-infiltrating lymphocytes, most of which were CD8-positive T cells. In conclusion, there were no significant differences in clinicopathological characteristics between LR-HCC and non-LR-HCC, except for gross and LR microscopic features. CCL20 expression in LR-HCC may contribute to infiltration of large numbers of CD8-positive lymphocytes.

Intraductal papilloma with atypical ductal hyperplasia and neuroendocrine differentiation as a possible precursor lesion of solid papillary carcinoma.

Breast papillary neoplasms include a wide range of tumor types, and their pathological diagnosis is sometimes difficult. Furthermore, the etiology of these lesions is still not fully understood. We report the case of a 72-years-old woman referred to our hospital with bloody discharge from the right nipple. An imaging study detected a cystic lesion, including a solid component contiguous with the mammary duct, in the subareolar region. The lesion was then removed by segmental mastectomy. Pathological examination of the resected specimen revealed an intraductal papilloma with atypical ductal hyperplasia. Moreover, the atypical ductal epithelial cells expressed neuroendocrine markers. The presence of an intraductal papillary lesion with neuroendocrine differentiation suggests solid papillary carcinoma. Thus, this case suggests that intraductal papilloma could be a precursor of solid papillary carcinoma.

Prognostic impact of vessels encapsulating tumor clusters and macrotrabecular patterns in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) shows a high mortality rate. A macrotrabecular (MT) pattern and vessels encapsulating tumor clusters (VETC) pattern have been reported as aggressive histological patterns in HCC. However, their cut-off values have been contentious. METHOD: Nine hundred eighty-five cases of previously diagnosed HCC were enrolled. The percentage areas of the MT and/or VETC pattern with ≥ 5% at every 10% increment were assessed. Clinicopathological analysis including patients' prognosis was conducted. RESULT: One hundred fifty-eight and eighty-four cases were accompanied by 5-49% and ≥ 50% MT components, respectively. Two hundred six and twenty-nine cases had 5-49% and ≥ 50% VETC components, respectively. Cases with these histological patterns in common had aggressive characteristics and worse prognosis compared to cases with none of these patterns. The presence of 5-49% VETC pattern was independent worse prognostic factor in overall survival (P = 0.046). HCCs with the MT pattern and the VETC pattern were significantly accompanied by the VETC pattern and the MT pattern (P < 0.001), respectively. CONCLUSION: As even 5% of the MT pattern and/or VETC pattern affected the prognosis of patients with HCC, the amount of these pattern should be described in pathological reports. This information could be useful in expecting patients' prognosis and providing proper post-operative treatments.

Predictive and Prognostic Value of SUOX Expression in Pancreatic Ductal Adenocarcinoma.

BACKGROUND/AIM: Sulphite oxidase (SUOX) is a metalloenzyme that catalyses ATP synthesis via oxidative phosphorylation in the mitochondria. Although SUOX has been reported to affect the invasiveness and differentiation of cancer cells, its clinicopathological significance in pancreatic adenocarcinoma (PDAC) remains unclear. In this study, we investigated the utility of SUOX expression as a prognostic factor in PDAC. PATIENTS AND METHODS: This study included 56 patients with PDAC who underwent pancreatic resection at the Kurume University Hospital between 2014 and 2018. SUOX immunohistochemistry was evaluated using tissue microarray specimens from patients. Patients were classified into a high SUOX expression group (≥10% of cells stained) or a low SUOX expression group (<10% of cells stained), and the associations of SUOX with clinicopathological characteristics and survival were analysed. Statistical analysis was performed using Cox regression analysis, the Kaplan-Meier method, and log-rank test. RESULTS: SUOX was expressed in the cytoplasm of normal pancreatic ductal epithelium, pancreatic acinar cells, and islets of Langerhans. Although we did not find any significant correlation between SUOX expression and clinicopathological factors, SUOX was identified as an independent prognostic factor based on univariate and multivariate analyses. Pathological stage was also an independent prognostic factor. The high SUOX expression group showed a significantly poorer prognosis than the low SUOX expression group (p=0.018). CONCLUSION: SUOX-mediated mitochondrial metabolism in PDAC may be a factor influencing prognosis and SUOX may be a potential novel prognostic biomarker.

Utility of sonic hedgehog and keratin 8/18 immunohistochemistry for detecting ballooned hepatocytes.

AIMS: Ballooned hepatocytes represent liver cell degeneration and are histological hallmarks in the diagnosis of non-alcoholic steatohepatitis, a severe form of non-alcoholic fatty liver disease. However, the identification of ballooned hepatocytes is often difficult, especially in the clinical setting of patients with other chronic liver diseases. In this study, we investigated the utility of immunostaining for positive sonic hedgehog (SHh) protein and negative Keratin 8/18 (K8/18) expression on ballooned hepatocytes. METHODS AND RESULTS: Immunohistochemistry for SHh and K8/18 was evaluated independently by two experienced liver pathologists in non-tumorous liver tissue from 100 cases of resected hepatocellular carcinoma of various aetiology. The degree of hepatocyte ballooning was scored as follows: 0, none; 1, few; 2, many ballooned hepatocytes. These evaluations were performed using routine haematoxylin and eosin (H&E) staining, followed by immunostaining for SHh or K8/18. Using SHh or K8/18 immunostaining combined with H&E staining, the score of ballooned hepatocytes was upgraded in 20 and 19 cases, and downgraded in none and 2 cases, respectively. The percentage of observed agreement for ballooned hepatocytes scoring was 85% and 92%, and the weighted kappa value was 0.806 and 0.893 with SHh or K8/18 immunohistochemistry. Considering the immunohistochemistry results, background liver disease diagnosis was changed in 15 out of 100 cases (15%) evaluated. CONCLUSIONS: SHh and K8/18 immunohistochemistry are useful in detecting ballooned hepatocytes, regardless of background liver disease, and improving pathological diagnosis accuracy.

Laparoscopic left hepatectomy for a patient with intrahepatic cholangiocarcinoma metastasis in the falciform ligament: a case report.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is primary cancer of the liver with poor prognosis because of its high potential for recurrence and metastasis. We experienced a rare case of ICC with hematogenous metastasis to the falciform ligament. We aimed to clarify the route of metastasis to the mesentery by increasing the accuracy of preoperative imaging and establish a hepatectomy to control cancer. CASE PRESENTATION: An 85-year-old woman was referred to our hospital for a detailed study of progressively increasing liver tumors. She had no subjective symptoms. Her medical history showed hypertension, aneurysm clipping for cerebral hemorrhage, and gallstones. A detailed physical examination and laboratory data evaluation included tumor markers but did not demonstrate any abnormalities. On computed tomography scan, contrast-enhanced ultrasound, and magnetic resonance imaging with gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid, the tumor appeared to be located in liver segment IV, protruding outside the liver. It appeared to contain two distinct components; we suspected ICC in the intrahepatic tumor component. Laparoscopic observation revealed that the extrahepatic lesion was an intra-falciform ligament mass; laparoscopic left hepatectomy was performed. Microscopically, the main tumor in segment IV was 15 mm in diameter and was diagnosed as moderately and poorly differentiated ICC. The tumor of the intra-falciform ligament was not continuous with the main intrahepatic nodule and was also diagnosed as ICC with extensive necrosis. There were no infiltrates in the round ligament of the liver, and several tumor thrombi were found in the small veins of the falciform ligament. CONCLUSIONS: To date, there have been a few reports of metastases of primary liver cancer to the falciform ligament. At the time of preoperative imaging and pathological diagnosis, this case was suggestive of considering that the malignant liver tumor might be suspected of metastasizing to the falciform ligament. Our case improves awareness of this pathology, which can be useful in the future when encountered by hepatic specialists and surgeons.

Sulfite Oxidase Is a Novel Prognostic Biomarker of Advanced Gastric Cancer.

BACKGROUND/AIM: Sulfite oxidase (SUOX) is an enzyme present in the mitochondria, which has been demonstrated to be correlated with various malignant tumours. MATERIALS AND METHODS: We evaluated SUOX expression in tissues of 98 cases of advanced gastric cancer and performed a clinicopathological assessment for metrics. RESULTS: Among 98 cases, 55 cases were classified into the SUOX low expression group, and 43 cases into the SUOX high expression group. There were more pStage IV cases in the low expression group. The median overall survival of the low expression group was shorter than that of the high expression group (p=0.020). In univariate and multivariate analysis, SUOX low expression level (p=0.039) and pStage (p<0.001) were independent prognostic factors. CONCLUSION: SUOX is an independent prognostic factor. Therefore, SUOX expression could also serve as a useful marker for elucidating the mechanism of gastric cancer proliferation and progression.

RBM10-TFE3 renal cell carcinoma characterised by paracentric inversion with consistent closely split signals in break-apart fluorescence in-situ hybridisation: study of 10 cases and a literature review.

AIMS: Xp11 rearrangement in renal cell carcinoma (RCC) typically involves gene fusion to the gene encoding transcription factor E3 (TFE3), a member of the microphthalmia-associated transcription factor family on chromosome Xp11.2. Dual-colour break-apart fluorescence in-situ hybridisation (FISH) is recommended to confirm histological diagnoses. Recently, RNA-binding motif protein 10 (RBM10), encoded by a gene on chromosome Xp11.3, was identified as a chimeric partner of TFE3; thus, RBM10-TFE3 fusion results from paracentric inversion. RBM10-TFE3 RCC may yield a false-negative result in FISH analysis of TFE3 expression. The aim of the present study was to investigate the clinicopathological features of RBM10-TFE3 RCC. METHODS AND RESULTS: Ten patients with RBM10-TFE3 RCC aged 31-71 years were investigated. Histological analysis, immunostaining, dual-colour break-apart FISH for TFE3, reverse transcription polymerase chain reaction and sequencing analysis were performed. No patient had a history of exposure to chemotherapy. Two of these patients died of RCC, and three were alive but developed metastases. Microscopically, the tumours were composed of a mixed architecture of tubulocystic and papillary patterns with scattered psammoma bodies. The tumours showed strong nuclear immunoreactivity for TFE3. FISH showed consistent closely spaced split signals in the RCCs of four patients, and polysomic signals with occasional closely spaced split signals in the RCCs of six patients. Of the latter six patients, five had renal failure, and four developed tumours in kidneys subjected to haemodialysis. CONCLUSIONS: The present study suggests that the carcinogenesis of RBM10-TFE3 RCC in some, but not all, patients may be associated with chronic kidney disease. The aggressive nature of RBM10-TFE3 RCC should be considered, as five patients experienced metastases.