Clinicopathological differences between EGFR mutated and EGFR wild-type lung adenocarcinoma with papillary predominant pattern.

OBJECTIVES: We aimed to reveal the clinicopathological differences between epidermal growth factor receptor (EGFR)-mutated and wild-type (WT) lung adenocarcinoma (LUAD) focusing on the predominant subtype. METHODS: This study included 352 with EGFR mutation and 370 with WT patients in consecutive stage I LUAD classified by the predominant subtype, and their clinicopathological characteristics and prognosis were analyzed. Using the Cancer Genome Atlas Program (TCGA) cohort, we analyzed differences in gene expression between EGFR mutation and WT groups. Furthermore, we performed immunohistochemical evaluations for 46 with EGFR mutation and 47 with WT patients in consecutive stage I papillary predominant adenocarcinoma (PPA). RESULTS: Compared to the PPA with WT [n = 115], those with EGFR mutation [n = 99] exhibited smaller invasive size (p = 0.03) and less frequent vessel invasion (p < 0.01). However, PPA with EGFR mutation showed significantly worse 5-ys recurrence-free survival (RFS) rates compared to those with WT (70.6 % versus 83.3 %, p = 0.03). Contrarily, no significant differences were observed in other predominant subtypes. In the TCGA cohort, PPA with EGFR mutation tended to show higher expression of galectin-3, which is associated with tumor metastasis and resistance to anoikis, compared to those with WT (p = 0.06). Immunohistochemical evaluation revealed that galectin-3 expression was significantly higher in PPA with EGFR mutation than in those with WT (p < 0.01). CONCLUSIONS: The prognosis of PPA with EGFR mutation proved to be less favorable compared to that with WT, and galectin-3 is highly expressed in EGFR-mutated PPA.

Conversion surgery after successful response to chemotherapy (S-1 + oxaliplatin + nivolumab) in a patient with stage IV gastric cancer with peritoneal metastasis (P1, CY1): a case report.

We here present a case report of a patient with Stage IV gastric cancer with peritoneal metastasis (P1, CY1) who underwent conversion surgery after a successful response to chemotherapy (S-1 + oxaliplatin + nivolumab). The patient was a woman in her 60 s. Her chief complaint was epigastric pain. Upper gastrointestinal endoscopy showed Type 4 advanced carcinoma on the lesser curvature of the gastric body. Biopsy showed Group 5 (poorly differentiated adenocarcinoma) and HER2 was negative. Staging laparoscopy revealed seeding in the round ligament of the liver (P1) and adenocarcinoma cells in ascites (CY1). Ten courses of chemotherapy (S-1 + oxaliplatin + nivolumab) were administered, after which contrast-enhanced computed tomography showed that the primary tumor had shrunk and seeding was no longer detectable. Upper gastrointestinal endoscopy revealed scar-like changes. A second staging laparoscopy revealed that ascites cytology was negative and a biopsy of the round ligament of the liver showed no malignant cells (P0, CY0). Conversion surgery comprising laparoscopic total gastrectomy with D2 lymph node dissection and resection of the round ligament of the liver was performed. The postoperative course was uneventful. Histopathological examination of the resected specimen revealed no tumor cells in the gastric mesentery or the round ligament of the liver. The pathological diagnosis was gastric cancer [M, U, L, Less, Ant, Post, type4, T3(SS), N0, M0 (H0, P0, CY0), ypStage IIA]. Adjuvant chemotherapy (S-1) was commenced. The patient is still alive 7 months later with no evidence of recurrence.

Histological and immunohistochemical analysis of epithelial cells in epidermoid cysts in intrapancreatic accessory spleen.

BACKGROUND: Epidermoid cysts in intrapancreatic accessory spleen (ECIPAS) are a rare lesion. Its pathogenesis, including the origin of cystic epithelium, is not well established. We aimed to elucidate new aspects of the pathological features of ECIPAS to clarify its pathogenesis. METHODS: Six cases of ECIPAS were included in this study. As well as histopathological analysis, to elucidate the features and nature of cystic epithelial cells, immunohistochemical analysis including Pbx1 and Tlx1 and imaging mass spectrometry was performed. RESULTS: Histologically, the cysts were covered by either monolayered or multilayered epithelium. Immunohistochemistry revealed that the epithelial cells in multilayered epithelium exhibited different attributes between the basal and superficial layers. Few epithelial cells had abundant clear cytoplasm and were immunohistochemically positive for adipophilin, suggesting lipid-excreting function. The intracystic fluid contained cholesterol clefts and foamy macrophages, and imaging mass spectrometry revealed the accumulation of lipids. Immunohistochemical analysis indicated that the epithelial cells were positive for Pbx1 in some cases. CONCLUSION: Novel histological features of epithelial cells of ECIPAS were indicated. Although more cases need to be evaluated, we propose that the cause of ECIPAS may be different from that of pancreatic ductal origin. J. Med. Invest. 70 : 251-259, February, 2023.

Definitive Confirmation of Erythropoietic Protoporphyria via Re-biopsy Three Years After Initial Liver Biopsy at Age 15.

Erythropoietic protoporphyria (EPP) is a rare inherited disorder of porphyrin metabolism that can cause liver damage and cholestatic hepatocellular failure. We report a case of EPP in a teenaged male who underwent liver biopsy for investigation of liver dysfunction of unknown cause. The diagnosis was not made until a re-biopsy approximately three years later, when the patient presented with recurrent skin lesions and elevated blood and urinary protoporphyrin levels. The liver biopsies contained brownish deposits that exhibited birefringence under polarized light and porphyrin fluorescence under fluorescence spectroscopy. EPP should be considered in young patients with unexplained liver dysfunction, skin symptoms, and seasonal changes in symptoms. Fluorescence spectroscopy of liver biopsy tissue can be a useful tool in the diagnosis of EPP.

Accumulation of α-synuclein in hepatocytes in nonalcoholic steatohepatitis and its usefulness in pathological diagnosis.

BACKGROUNDS: Nonalcoholic steatohepatitis (NASH) is characterized by fat deposition, inflammation, and hepatocellular damage. The diagnosis of NASH is confirmed pathologically, and hepatocyte ballooning is an important finding for definite diagnosis. Recently, α-synuclein deposition in multiple organs was reported in Parkinson's disease. Since it was reported that α-synuclein is taken up by hepatocytes via connexin 32, the expression of α-synuclein in the liver in NASH is of interest. The accumulation of α-synuclein in the liver in NASH was investigated. Immunostaining for p62, ubiquitin, and α-synuclein was performed, and the usefulness of immunostaining in pathological diagnosis was examined. METHODS: Liver biopsy tissue specimens from 20 patients were evaluated. Several antibodies against α-synuclein, as well as antibodies against connexin 32, p62, and ubiquitin were used for immunohistochemical analyses. Staining results were evaluated by several pathologists with varying experience, and the diagnostic accuracy of ballooning was compared. RESULTS: Polyclonal α-synuclein antibody, not the monoclonal antibody, reacted with eosinophilic aggregates in ballooning cells. Expression of connexin 32 in degenerating cells was also demonstrated. Antibodies against p62 and ubiquitin also reacted with some of the ballooning cells. In the pathologists' evaluations, the highest interobserver agreement was obtained with hematoxylin and eosin (H&E)-stained slides, followed by slides immunostained for p62 and α-synuclein, and there were cases with different results between H&E staining and immunostaining CONCLUSION: These results indicate the incorporation of degenerated α-synuclein into ballooning cells, suggesting the involvement of α-synuclein in the pathogenesis of NASH. The combination of immunostaining including polyclonal α-synuclein may contribute to improving the diagnosis of NASH.

Spontaneous Occurrence of Various Types of Hepatocellular Adenoma in the Livers of Metabolic Syndrome-Associated Steatohepatitis Model TSOD Mice.

Male Tsumura-Suzuki Obese Diabetes (TSOD) mice, a spontaneous metabolic syndrome model, develop non-alcoholic steatohepatitis and liver tumors by feeding on a standard mouse diet. Nearly 70% of liver tumors express glutamine synthetase (GS), a marker of hepatocellular carcinoma. In contrast, approximately 30% are GS-negative without prominent nuclear or structural atypia. In this study, we examined the characteristics of the GS-negative tumors of TSOD mice. Twenty male TSOD mice were sacrificed at 40 weeks and a total of 21 tumors were analyzed by HE staining and immunostaining of GS, liver fatty acid-binding protein (L-FABP), serum amyloid A (SAA), and beta-catenin. With immunostaining for GS, six (29%) tumors were negative. Based on the histological and immunohistological characteristics, six GS-negative tumors were classified into several subtypes of human hepatocellular adenoma (HCA). One large tumor showed generally similar findings to inflammatory HCA, but contained small atypical foci with GS staining and partial nuclear beta-catenin expression suggesting malignant transformation. GS-negative tumors of TSOD mice contained features similar to various subtypes of HCA. Different HCA subtypes occurring in the same liver have been reported in humans; however, the diversity of patient backgrounds limits the ability to conduct a detailed, multifaceted analysis. TSOD mice may share similar mechanisms of HCA development as in humans. It is timely to review the pathogenesis of HCA from both genetic and environmental perspectives, and it is expected that TSOD mice will make further contributions in this regard.

Verification of the Impact of Blood Glucose Level on Liver Carcinogenesis and the Efficacy of a Dietary Intervention in a Spontaneous Metabolic Syndrome Model.

Metabolic syndrome (MS) is a risk factor for type 2 diabetes mellitus, vascular inflammation, atherosclerosis, and renal, liver, and heart diseases. Non-alcoholic steatohepatitis (NASH) is a progressive representative liver disease and may lead to the irreversible calamities of cirrhosis and hepatocellular carcinoma. Metabolic disorders such as hyperglycemia have been broadly reported to be related to hepatocarcinogenesis in NASH; however, direct evidence of a link between hyperglycemia and carcinogenesis is still lacking. Tsumura Suzuki Obese Diabetic (TSOD) mice spontaneously develop metabolic syndrome, including obesity, insulin resistance, and NASH-like liver phenotype, and eventually develop hepatocellular carcinomas. TSOD mice provide a spontaneous human MS-like model, even with significant individual variations. In this study, we monitored mice in terms of their changes in blood glucose levels, body weights, and pancreatic and liver lesions over time. As a result, liver carcinogenesis was delayed in non-hyperglycemic TSOD mice compared to hyperglycemic mice. Moreover, at the termination point of 40 weeks, liver tumors appeared in 18 of 24 (75%) hyperglycemic TSOD mice; in contrast, they only appeared in 5 of 24 (20.8%) non-hyperglycemic mice. Next, we investigated three kinds of oligosaccharide that could lower blood glucose levels in hyperglycemic TSOD mice. We monitored the levels of blood and urinary glucose and assessed pancreatic lesions among the experimental groups. As expected, significantly lower levels of blood and urinary glucose and smaller deletions of Langerhans cells were found in TSOD mice fed with milk-derived oligosaccharides (galactooligosaccharides and lactosucrose). At the age of 24 weeks, mild steatohepatitis was found in the liver but there was no evidence of liver carcinogenesis. Steatosis in the liver was alleviated in the milk-derived oligosaccharide-administered group. Taken together, suppressing the increase in blood glucose level from a young age prevented susceptible individuals from diabetes and the onset of NAFLD/NASH, as well as carcinogenesis. Milk-derived oligosaccharides showed a lowering effect on blood glucose levels, which may be expected to prevent liver carcinogenesis.

Triple-negative breast cancer and basal-like subtype†: Pathology and targeted therapy.

Triple-negative breast cancer (TNBC) is a heterogenous disease. For personalized medicine, it is essential to identify and classify tumor subtypes to develop effective therapeutic strategies. Although gene expression profiling has identified several TNBC subtypes, classification of these tumors remains complex. Most TNBCs exhibit an aggressive phenotype, but some rare types have a favorable clinical course. In this review, we summarize the classification and characteristics related to the various TNBC subtypes, including the rare types. Therapeutic methods that are suitable for each subtype are also discussed. Of the intrinsic breast cancer subtypes identified by gene expression analysis, the basal-like subtype specifically displayed decreased expression of an estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) cluster. We also present results that characterize the TNBC and basal-like phenotypes. TNBC may be categorized into four major classes : basal-like, immune-enriched, mesenchymal, and luminal androgen receptor. Therapeutic strategies for each subtype have been proposed along with newly approved targeted therapies for TNBC, such as immune checkpoint inhibitors. Understanding the classification of TNBC based on gene expression profiling in association with clinicopathological factors will facilitate accurate pathological diagnosis and effective treatment selection. J. Med. Invest. 68 : 213-219, August, 2021.

KH-type splicing regulatory protein is involved in esophageal squamous cell carcinoma progression.

KH-type splicing regulatory protein (KHSRP) is a multifunctional RNA-binding protein, which is involved in several post-transcriptional aspects of RNA metabolism, including microRNA (miRNA) biogenesis. It affects distinct cell functions in different tissues and can have an impact on various pathological conditions. In the present study, we investigated the oncogenic functions of KHSRP and their underlying mechanisms in the pathogenesis of esophageal squamous cell carcinoma (ESCC). KHSRP expression levels were elevated in ESCC tumors when compared with those in non-tumorous tissues by immunohistochemistry, and cytoplasmic KHSRP overexpression was found to be an independent prognosticator for worse overall survival in a cohort of 104 patients with ESCC. KHSRP knockdown inhibited growth, migration, and invasion of ESCC cells. KHSRP knockdown also inhibited the maturation of cancer-associated miRNAs, such as miR-21, miR-130b, and miR-301, and induced the expression of their target mRNAs, such as BMP6, PDCD4, and TIMP3, resulting in the inhibition of epithelial-to-mesenchymal transition. Our findings uncover a novel oncogenic function of KHSRP in esophageal tumorigenesis and implicate its use as a marker for prognostic evaluation and as a putative therapeutic target in ESCC.

Tumor-promoting function and prognostic significance of the RNA-binding protein T-cell intracellular antigen-1 in esophageal squamous cell carcinoma.

T-cell intracellular antigen-1 (TIA1) is an RNA-binding protein involved in many regulatory aspects of mRNA metabolism. Here, we report previously unknown tumor-promoting activity of TIA1, which seems to be associated with its isoform-specific molecular distribution and regulation of a set of cancer-related transcripts, in esophageal squamous cell carcinoma (ESCC). Immunohistochemical overexpression of TIA1 ectopically localized in the cytoplasm of tumor cells was an independent prognosticator for worse overall survival in a cohort of 143 ESCC patients. Knockdown of TIA1 inhibited proliferation of ESCC cells. By exogenously introducing each of two major isoforms, TIA1a and TIA1b, only TIA1a, which was localized to both the nucleus and cytoplasm, promoted anchorage-dependent and anchorage-independent ESCC cell proliferation. Ribonucleoprotein immunoprecipitation, followed by microarray analysis or massive-parallel sequencing, identified a set of TIA1-binding mRNAs, including SKP2 and CCNA2. TIA1 increased SKP2 and CCNA2 protein levels through the suppression of mRNA decay and translational induction, respectively. Our findings uncover a novel oncogenic function of TIA1 in esophageal tumorigenesis, and implicate its use as a marker for prognostic evaluation and as a therapeutic target in ESCC.

HER2 amplification detected in the circulating DNA of patients with gastric cancer: a retrospective pilot study.

BACKGROUND: We used real-time quantitative polymerase chain reaction (rqPCR) to detect human epidermal growth factor receptor 2 (HER2) amplification in the circulating cell-free DNA (cfDNA) of patients with gastric cancer (GC), which shows the spatial and temporal intrinsic heterogeneity of HER2 expression/copy number during progression, for liquid biopsy and treatment monitoring. METHODS: We first enrolled 52 patients with advanced GC who underwent surgery and 40 healthy volunteers. For patients with GC, plasma cfDNA was obtained before surgery (43 patients) and during postoperative treatment (nine of 43 patients). After ribonuclease P RNA component H1 (RPPH1) had been selected as a reference gene for HER2 CN assessment by rqPCR in GC tumours and plasma, plasma HER2-to-RPPH1 ratios were determined retrospectively in a development cohort and an additional independent validation cohort. RESULTS: The HER2-to-RPPH1 ratio of GC tissues determined by rqPCR was concordant with routinely determined HER2 status. The plasma HER2-to-RPPH1 ratio was significantly higher for patients with HER2-positive tumours than for those with HER2-negative tumours. The sensitivity and specificity of the plasma HER2-to-RPPH1 ratio test were 0.539 and 0.967, respectively, in the development cohort, and 0.667 and 1.000, respectively, in the validation cohort. HER2 amplifications acquired and lost during tumour progression and treatment, respectively, were apparently detected by repeated assessments of plasma HER2-to-RPPH1 ratios during postoperative treatment. CONCLUSION: Our preliminary data demonstrated the potential clinical use of circulating cfDNA to detect HER2 amplification as a therapeutic marker to detect and monitor HER2 CN status for effective molecular targeted therapy in patients with GC.