Bile Duct Epithelium Research Articles

Perihilar cholangiocarcinoma masquerading as intrahepatic cholestasis of pregnancy: a case report and review of the literature

Cholangiocarcinoma (CCA) is a tumor that arises from the epithelium of the intrahepatic bile ducts. It is rarely diagnosed in individuals under 40 years of age and has a very aggressive nature: 95% of patients die within 5 years. We present the first detailed report of a case of perihilar CCA (pCCA) presenting during pregnancy masquerading as intrahepatic cholestasis of pregnancy (ICP). First, the patient exhibited typical pruritus, particularly in her limbs; second, a raised biomarker of total bile acid (TBA) was noted; third, the onset occurred in the second trimester, aligning with the epidemiological profile; and finally, importantly, there was no mass detected in her liver. First-line drugs were given to treat ICP, but they failed, and ultimately, the condition was identified as pCCA. Following an inadequate excision, traditional Chinese medicine was administered. After 26 months, she succumbed to cachexia. As gestational symptoms are sometimes associated with pregnancy-related disorders, pCCA in pregnant women is frequently misdiagnosed. Symptoms such as jaundice, pruritus, and dilated bile ducts in pregnant women may indicate pCCA. In addition, the appropriate treatment for pCCA in pregnant women may be surgery or chemotherapy; if surgery is not an option, chemotherapy may also help extend the gestational week. Our work is important and can educate on the diagnosis and treatment of pregnancy-related diseases, such as ICP and pCCA.

Bile Acids-Based Therapies for Primary Sclerosing Cholangitis: Current Landscape and Future Developments.

Primary sclerosing cholangitis (PSC) is a rare, chronic liver disease with no approved therapies. The ursodeoxycholic acid (UDCA) has been widely used, although there is no evidence that the use of UDCA delays the time to liver transplant or increases survival. Several candidate drugs are currently being developed. The largest group of these new agents is represented by FXR agonists, including obeticholic acid, cilofexor, and tropifexor. Other agents that target bile acid metabolism are ASTB/IBAP inhibitors and fibroblasts growth factor (FGF)19 analogues. Cholangiocytes, the epithelial bile duct cells, play a role in PSC development. Recent studies have revealed that these cells undergo a downregulation of GPBAR1 (TGR5), a bile acid receptor involved in bicarbonate secretion and immune regulation. Additional agents under evaluation are PPARs (elafibranor and seladelpar), anti-itching agents such as MAS-related G-protein-coupled receptors antagonists, and anti-fibrotic and immunosuppressive agents. Drugs targeting gut bacteria and bile acid pathways are also under investigation, given the strong link between PSC and gut microbiota.

SRPK Inhibitors Reduce the Phosphorylation and Translocation of SR Protein Splicing Factors, thereby Correcting BIN1, MCL-1 and BCL2 Splicing Errors and Enabling Apoptosis of Cholangiocarcinoma Cells.

Cholangiocarcinoma (CCA) is a malignancy of the bile duct epithelium that is commonly found in the Thai population. CCA has poor prognosis and a low survival rate due to the lack of early diagnosis methods and the limited effectiveness of current treatments. A number of oncogenic spliced-transcripts resulting from mRNA splicing errors have been reported in CCA, and aberrant mRNA splicing is suspected to be a key driver of this cancer type. The hyperphosphorylation of serine/arginine rich-splicing factors (SRSFs) by serine/arginine protein kinases (SRPKs) causes them to translocate to the nucleus where they facilitate gene splicing errors that generate cancer-related mRNA/protein isoforms. The correlation between SRPK expression and the survival of CCA patients was analyzed using data from The Cancer Genome Atlas (TCGA) dataset. The effect of SRPK inhibitors (SRPIN340 and SPHINX31) on two CCA cell lines (KKU-213A and TFK-1) was also investigated. The induction of cell death was studied by Calcein-AM/PI staining, AnnexinV/7AAD staining, immunofluorescence (IF), and Western blotting (WB). The phosphorylation and nuclear translocation of SRSFs was tracked by WB and IF, and the repair of splicing errors was examined by Reverse Transcription-Polymerase Chain Reaction (RT-PCR). High levels of SRPK1 and SRPK2 transcripts, and in particular SRPK1, correlated with shorter survival in CCA patients. SRPIN340 and SPHINX31 increased the number of dead and apoptotic cells in a dose-dependent manner. CCA also showed diffuse expression of cytoplasmic cytochrome C and upregulation of cleaved caspase-3. Moreover, SRSFs showed low levels of phosphorylation, resulting in the accumulation of cytoplasmic SRSF1. To link these phenotypes with aberrant gene splicing, the apoptosis-associated genes Bridging Integrator 1 (BIN1), Myeloid cell leukemia factor 1 (MCL-1) and B-cell lymphoma 2 (BCL2) were selected for further investigation. Treatment with SRPIN340 and SPHINX31 decreased anti-apoptotic BIN1+12A and increased pro-apoptotic MCL-1S and BCL-xS. The SRPK inhibitors SRPIN340 and SPHINX31 can suppress the phosphorylation of SRSFs and their nuclear translocation, thereby producing BIN1, MCL-1 and BCL2 isoforms that favor apoptosis and facilitate CCA cell death.

Cholangiocarcinoma: Consistent clinical, cytological, hematological, and biochemical findings and pathomorphology of the liver and kidney in five exotic dog breeds in Abeokuta, Nigeria

Background and Aim: Cholangiocarcinomas are malignant neoplasms that originate from any part of the bile duct epithelium. It is one of the most common liver tumors in dogs. This study described the clinical, cytological, hematological, biochemical, and pathomorphological findings of five cholangiocarcinoma cases in exotic breed dogs aged 2–5 years to aid in clinical diagnosis. Materials and Methods: This study used dogs presented at different times from 2012 to 2021 at the Veterinary Teaching Hospital, Federal University of Agriculture, Abeokuta. History, clinical signs, and vital parameters were recorded. Blood samples were collected for hematology and serum chemistry. Abdominocentesis was performed for cytological diagnosis. All dogs died during treatment, and postmortem examinations were performed. At postmortem, fine needle aspirates were collected from the liver and mesenteric lymph nodes and liver and kidney samples were fixed in 10% neutral-buffered formalin. Results: The dogs showed signs of severe malnutrition, jaundice, and bloating. The hematological analysis indicated anemia, neutrophilia without band neutrophils, and lymphopenia, indicative of a stress hemogram. The serum biochemistry test revealed lower levels of total proteins, albumin, and globulin and higher levels of serum enzymes. Abdominal fluid and mesenteric lymph node cytology revealed clusters of epithelial neoplastic cells. A postmortem examination revealed the liver’s nodular enlargement with the presence of button-like ulcers. Neoplastic epithelial cells are solid masses with hyperchromatic nuclei surrounded by fibrous connective tissues. Conclusion: Cholangiocarcinoma, diagnosed over a period of time in five exotic breeds of dog, consistently presents with the same clinical and postmortem findings, aiding in clinical diagnosis. However, the diagnosis of the disease is not possible in the early stage because of the absence of specific clinical signs. In dogs and possibly other animal species presenting with emaciation, lethargy, icterus, and distended abdomen, cholangiocarcinoma should be suspected, and cytological examination of the abdominal fluid and lymph node aspirates should be performed despite the absence of advanced equipment. Keywords: biochemical indices, cholangiocarcinoma, clinical signs, cytological findings, hematological findings, histopathology, malignancy, Nigeria, postmortem finding.

Effect of TTYH3 on cholangiocarcinoma invasion, metastasis and lymph node metastasis through Wnt/β-catenin pathway.

57 Background: Cholangiocarcinoma is a malignant tumor originating from the bile duct epithelium. Metastasis is an important factor affecting the prognosis of cholangiocarcinoma. To explore the role and mechanism of calcium-activated chloride channel protein Tweety homolog 3 (TTYH3) in cholangiocarcinoma metastasis. Methods: TTYH3 was overexpressed and knocked down in cholangiocarcinoma cells, and in vitro experiments were performed to clarify the biological function of TTYH3 in cholangiocarcinoma. Experiments on xenograft tumor mice model have shown that TTYH3 promotes tumorigenesis of cholangiocarcinoma cells. Analysis of the relationship between TTYH3 expression and patient prognosis and lymph node metastasis in cholangiocarcinoma tissue specimens. Exosomes were extracted from bile of patients with cholangiocarcinoma and bile duct stones, and the expression of TTYH3 in exosomes was compared. TTYH3 overexpressed exosomes were used to treat endothelial cells, and their function and mechanism in promoting lymphangiogenesis were analyzed. Results: In vitro experiments confirmed that TTYH3 promoted the migration and invasion of cholangiocarcinoma cell line QBC939. In vivo experiments confirmed that TTYH3 promotes the tumorigenesis of cholangiocarcinoma cells. TTYH3 promotes epithelial-to-mesenchymal transition of cholangiocarcinoma cells through the Wnt/β-catenin signaling pathway. TTYH3 promotes cholangiocarcinoma cell self-expression through positive feedback. TTYH3 is highly expressed in cholangiocarcinoma tissues. Patients with high TTYH3 expression have poor prognosis and a high incidence of lymph node metastasis. The TTYH3 protein content of bile exosomes in patients with cholangiocarcinoma is increased, which promotes the invasion and metastasis of cholangiocarcinoma cells, while also promoting lymphangiogenesis and increased permeability. TTYH3 promotes the uptake of exosomes by lymphatic cells and promotes lymphangiogenesis by regulating the influx of calcium ions and chloride ions in lymphatic cells. Conclusions: TTYH3 promotes the invasion and metastasis of cholangiocarcinoma cells through the Wnt/β-catenin signaling pathway, and exosome TTYH3 promotes lymphangiogenesis and lymph node metastasis.

Morphological changes in the biliary mucosa in pediatric patients with congenital biliary dilatation are more influenced by the duration of amylase exposure than by amylase levels in the gallbladder.

We investigated the relationship between bile amylase (AMY) levels and biliary epithelial changes in pancreaticobiliary maljunction (PBM), a congenital anomaly characterized by pancreaticobiliary reflux due to duct fusion outside the duodenal wall. We enrolled 43 children with congenital biliary dilatation (CBD) of Todani types Ia, Ic, and IVa who underwent surgery at the Hokkaido Medical Center for Child Health and Rehabilitation between November 2007 and June 2023. We defined total AMY exposure in bile as bile AMY levels multiplied by the patient's age (months), representing amount of estimated AMY exposure until surgery. We retrospectively investigated the relationships between bile AMY levels and clinicopathological findings. All patients exhibited hyperplasia in the gallbladder and bile duct epithelium, with dysplasia observed in 13 cases, but no carcinoma. Exposure to bile AMY ≥ 662,400IU/L × months was an independent risk factor for dysplasia. The amount of estimated AMY exposure in bile rather than AMY levels in the bile is an independent risk factor for dysplasia in the biliary mucosa.

Pathologic characterization of precursors and cholangiocarcinoma referring to peribiliary capillary plexus: a new pathologic approach to bile duct neoplasm.

The peribiliary capillary plexus (PCP) regularly and densely lines the basal side of the lining epithelia of normal bile ducts. To determine the pathology of the PCP in high-grade biliary intraepithelial neoplasms (BilINs) and intraductal papillary neoplasms of the bile duct (IPNBs), a precursor of cholangiocarcinoma (CCA), and CCA. Seventy-six cases of surgically resected high-grade BilIN and 83 cases of IPNB were histopathologically examined using endothelial immunostaining of PCP; all cases of high-grade BilIN and 40 cases of IPNB were associated with invasive CCA. Invasive and preinvasive neoplasms were pathologically examined referring to a two-layer pattern composed of biliary lining epithelia and underlying PCP unique to the bile duct. All high-grade BilIIN cases had an underlying single layer of capillaries, similar to PCP (PCP-like capillaries). In 43% of the 83 cases of IPNB, these capillaries were regularly distributed in almost all stalks and intervening stroma of intraluminal neoplastic components, while in the remaining 57% of IPNB, capillaries were sparsely or irregularly distributed in intraluminal components showing cribriform or solid growth patterns composed of striking atypical neoplastic epithelia. Invasive carcinomas associated with high-grade BilIN and IPNB were not lined with capillaries. The loss of PCP-like capillaries underlying high-grade BilIN and in stalks or stroma of IPNB may be involved in the malignant progression of these precursors. Immunostaining of PCP could be a new pathological tool for the evaluation of malignant progression and vascular supply in CCA and its precursors.

Promotion of perineural invasion of cholangiocarcinoma by Schwann cells via nerve growth factor.

Cholangiocarcinoma (CCA), a highly lethal tumor of the hepatobiliary system originating from bile duct epithelium, can be divided into the intrahepatic, hilar, and extrahepatic types. Due to its insidious onset and atypical early clinical symptoms, the overall prognosis is poor. One of the important factors contributing to the poor prognosis of CCA is the occurrence of perineural invasion (PNI), but the specific mechanisms regarding how it contributes to the occurrence of PNI are still unclear. The main purpose of this study is to explore the molecular mechanism leading to the occurrence of PNI and provide new ideas for clinical treatment. CCA cell lines and Schwann cells (SCs) were stimulated to observe the changes in cell behavior. SCs cocultured with tumor supernatant and SCs cultured in normal medium were subjected to transcriptome sequencing to screen the significantly upregulated genes. Following this, the two types of tumor cells were cultured with SC supernatant, and the changes in behavior of the tumor cells were observed. Nonobese diabetic-severe combined immunodeficiency disease (NOD-SCID) mice were injected with cell suspension supplemented with nerve growth factor (NGF) via the sciatic nerve. Four weeks later, the mice were euthanized and the tumor sections were removed and stained. Nerve invasion by tumor cells was common in CCA tissues. SCs were observed in tumor tissues, and the number of SCs in tumor tissues and the degree of PNI were much higher than were those in normal tissues or tissues without PNI. The overall survival time was shorter in patients with CCA with PNI than in patients without PNI. SCs were enriched in CCA tissues, indicating the presence of PNI and associated with poor prognosis in CCA patients. CCA was found to promote NGF secretion from SCs in vitro. After the addition of exogenous NGF in CCA cell culture medium, the proliferation activity and migration ability of CCA cells were significantly increased, suggesting that SCs can promote the proliferation and migration of CCA through the secretion of NGF. NGF, in turn, was observed to promote epithelial-mesenchymal transition in CCA through tropomyosin receptor kinase A (TrkA), thus promoting its progression. Tumor growth in mice shows that NGF can promote PNI in CCA. In CCA, tumor cells can promote the secretion of NGF by SCs, which promotes the progression of CCA and PNI by binding to its high-affinity receptor TrkA, leading to poor prognosis.

Quantitative proteomics analysis reveals possible anticancer mechanisms of 5'-deoxy-5'-methylthioadenosine in cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) is an aggressive cancer originating from bile duct epithelium, particularly prevalent in Asian countries with liver fluke infections. Current chemotherapy for CCA often fails due to drug resistance, necessitating novel anticancer agents. This study investigates the potential of 5'-deoxy-5'-methylthioadenosine (MTA), a naturally occurring nucleoside, against CCA. While MTA has shown promise against various cancers, its effects on CCA remain unexplored. We evaluated MTA's anticancer activity in CCA cell lines and drug-resistant sub-lines, assessing cell viability, migration, invasion, and apoptosis. The potential anticancer mechanisms of MTA were explored through proteomic analysis using LC-MS/MS and bioinformatic analysis. The results show a dose-dependent reduction in CCA cell viability, with enhanced effects on cancer cells compared to normal cells. Moreover, MTA inhibits growth, induces apoptosis, and suppresses cell migration and invasion. Additionally, MTA enhanced the anticancer effects of gemcitabine on drug-resistant CCA cells. Proteomics revealed the down-regulation of multiple proteins by MTA, affecting various molecular functions, biological processes, and cellular components. Network analysis highlighted MTA's role in inhibiting proteins related to mitochondrial function and energy derivation, crucial for cell growth and survival. Additionally, MTA suppressed proteins involved in cell morphology and cytoskeleton organization, important for cancer cell motility and metastasis. Six candidate genes, including ZNF860, KLC1, GRAMD1C, MAMSTR, TANC1, and TTC13, were selected from the top 10 most down-regulated proteins identified in the proteomics results and were subsequently verified through RT-qPCR. Further, KLC1 protein suppression by MTA treatment was confirmed through Western blotting. Additionally, based on TCGA data, KLC1 mRNA was found to be upregulated in the tissue of CCA patients compared to that of normal adjacent tissues. In summary, MTA shows promising anticancer potential against CCA by inhibiting growth, inducing apoptosis, and suppressing migration and invasion, while enhancing gemcitabine's effects. Proteomic analysis elucidates possible molecular mechanisms underlying MTA's anticancer activity, laying the groundwork for future research and development of MTA as a treatment for advanced CCA.

Liver-specific DICER1 syndrome model mice develop cystic liver tumors with defective primary cilia.

DICER1 syndrome is a tumor predisposition syndrome caused by familial genetic mutations in DICER1. Pathogenic variants of DICER1 have been discovered in many rare cancers, including cystic liver tumors. However, the molecular mechanisms underlying liver lesions induced by these variants remain unclear. In the present study, we sought to gain a better understanding of the pathogenesis of these variants by generating a mouse model of liver-specific DICER1 syndrome. The mouse model developed bile duct hyperplasia with fibrosis, similar to congenital hepatic fibrosis, as well as cystic liver tumors resembling those in Caroli's syndrome, intrahepatic cholangiocarcinoma, and hepatocellular carcinoma. Interestingly, the mouse model of DICER1 syndrome showed abnormal formation of primary cilia in the bile duct epithelium, which is a known cause of bile duct hyperplasia and cyst formation. These results indicated that DICER1 mutations contribute to cystic liver tumors by inducing defective primary cilia. The mouse model generated in this study will be useful for elucidating the potential mechanisms of tumorigenesis induced by DICER1 variants and for obtaining a comprehensive understanding of DICER1 syndrome. © 2024 The Pathological Society of Great Britain and Ireland.

Pathological, morphological, and molecular characterization of the infection by Brachycladium goliath in humpback whale Megaptera novaeangliae.

The humpback whale (Megaptera novaeangliae) is a cosmopolitan migratory, seasonal mysticete that frequents the Brazilian coast. Strands of specimens may occur during the migratory stay in the country. In 2021 and 2022, three live humpback whales stranded on the coast of Rio Grande do Sul and Santa Catarina states in southern Brazil. After euthanasia, specimens were necropsied, and organs were thoroughly examined for lesions. Grossly, in all three cases, the liver exhibited multifocal, irregular, firm, white areas on the hepatic capsule, which extended into the parenchyma. On the cut surface, the livers were yellow to pale brown with orangish to greenish areas, the bile ducts were prominent, thickened, and severely dilated, and leaf-shaped flukes were found inside of them. Additionally, one case showed moderate atrophy of the right hepatic lobe. The histological findings included dilation of bile ducts, hyperplasia of the bile duct epithelium, marked inflammatory infiltration of lymphocytes, plasma cells, and eosinophils, and portal fibrosis. The parasite Brachycladium goliath was both morphologically and molecularly identified based on diagnostic key for trematodes and the original description of the species, and the amplification and sequencing of the ITS-2 region, respectively. Even though hepatic injury was not the primary cause of stranding, it may have contributed to the debilitation of the whales. To the authors' knowledge, this is the first study that reports M. novaeangliae as a definitive host of B. goliath and that describes the lesions caused by the parasite in cetaceans.

Clinical significance of small extracellular vesicles in cholangiocarcinoma.

Cholangiocarcinoma is an aggressive and heterogeneous malignancy originating from the bile duct epithelium. It is associated with poor prognosis and high mortality. The global incidence of cholangiocarcinoma is rising, and there is an urgent need for effective early diagnosis and treatment strategies to reduce the burden of this devastating tumor. Small extracellular vesicles, including exosomes and microparticles, are nanoscale vesicles formed by membranes that are released both normally and pathologically from cells, mediating the intercellular transfer of substances and information. Recent studies have demonstrated the involvement of small extracellular vesicles in numerous biological processes, as well as the proliferation, invasion, and metastasis of tumor cells. The present review summarizes the tumorigenic roles of small extracellular vesicles in the cholangiocarcinoma microenvironment. Owing to their unique composition, accessibility, and stability in biological fluids, small extracellular vesicles have emerged as ideal biomarkers for use in liquid biopsies for diagnosing and outcome prediction of cholangiocarcinoma. Specific tissue tropism, theoretical biocompatibility, low clearance, and strong biological barrier penetration of small extracellular vesicles make them suitable drug carriers for cancer therapy. Furthermore, the potential value of small extracellular vesicle-based therapies for cholangiocarcinoma is also reviewed.

Stable two- and three-dimensional cholangiocyte culture systems from extrahepatic bile ducts of biliary atresia patients: use of structural and functional bile duct epithelium models for in vitro analyses

We herein report two- (2D) and three-dimensional (3D) culture methods of cholangiocytes originating from extrahepatic bile ducts of biliary atresia (BA) patients. Cells were stabilized for in vitro analyses, and 3D culture by two different methods showed the structural and functional features of cholangiocytes in the gel scaffold. First, cells were obtained from gallbladder contents or resected tissues of patients at surgery and then cultured in our original conditioned medium with a cocktail of signaling inhibitors that maintains the immaturity and amplification of cells. Cells were immortalized by inducing SV40T and hTERT genes using lentivirus systems. Immunostaining with CK19 and Sox9 antibodies confirmed the cells as cholangiocytes. 3D organoids were formed in Matrigel in two different ways: by forming spheroids or via vertical growth from 2D cell sheets (2 + 1D culture). Organoids generated with both methods showed the uptake and excretion of rhodamine-123, and duct-like structures were also found. Our culture methods are simpler than previously reported methods and still show the structural and functional characteristics of cholangiocytes. Thus, this system is expected to be useful for the in vitro investigation of cholangiocyte damage or regeneration in BA patients.

Pathological Responses in Asian House Shrews (Suncus murinus) to the Naturally Acquired Orientia tsutsugamushi Infection.

Scrub typhus is a re-emerging disease caused by Orientia tsutsugamushi, transmitted by mites belonging to the family Trombiculidae. Humans and rodents acquire the infection by the bite of larval mites/chiggers. Suncus murinus, the Asian house shrew, has been reported to harbor the vector mites and has been naturally infected with O. tsutsugamushi. The present study aimed to localize and record O. tsutsugamushi in the tissues and the host response in shrews naturally infected with O. tsutsugamushi. Sheehan's modified May-Grunwald Giemsa staining was carried out in 365 tissues from 87 animals, and rickettsiae were documented in 87 tissues from 20 animals. Immunohistochemical (IHC) staining, using polyclonal antibodies raised against selected epitopes of the 56-kDa antigen, was carried out, and 81/87 tissue sections were tested positive for O. tsutsugamushi. By IHC, in addition to the endothelium, the pathogen was also demonstrated by IHC in cardiomyocytes, the bronchiolar epithelium, stroma of the lungs, hepatocytes, the bile duct epithelium, the epithelium and goblet cells of intestine, the tubular epithelium of the kidney, and splenic macrophages. Furthermore, the pathogen was confirmed by real-time PCR using blood (n = 20) and tissues (n = 81) of the IHC-positive animals. None of the blood samples and only 22 out of 81 IHC-positive tissues were tested positive by PCR. By nucleotide sequencing of the 56-kDa gene, Gilliam and Karp strains were found circulating among these animals. Although these bacterial strains are highly virulent and cause a wide range of pathological alterations, hence exploring their adaptive mechanisms of survival in shrews will be of significance. Given that the pathogen localizes in various organs following a transient bacteremia, we recommend the inclusion of tissues from the heart, lung, intestine, and kidney of reservoir animals, in addition to blood samples, for future molecular surveillance of scrub typhus.

Abstract 1626: Clonal expansion in bile duct associated with chronic inflammation

Abstract Introduction: Chronic inflammation has been implicated in cancer development in many tissues and has recently been associated with promoted clonal expansion in non-cancer tissues. Primary sclerosing cholangitis (PSC) is a chronic progressive disease of unknown etiology affecting the bile ducts and has been associated with a substantially increased risk of cholangiocarcinoma. Clonal dynamics in the normal bile duct and PSC epithelium remains poorly understood because of the limited accessibility to normal/inflamed bile ducts. In this study, we established a method to detect somatic mutations accumulated in the bile duct epithelium and investigated a mutation rate in normal bile duct cells and clonal expansion in PSC epithelium. Methods: We established single cell-derived organoids from bile, which were subjected to whole genome sequencing to measure the age-related mutation rate in normal epithelial cell in the bile ducts. We next established organoids from multiple sites in perihilar bile ducts and collected epithelial samples from intrahepatic bile ducts obtained by laser-capture microdissection (LCM) from patients with PSC who underwent total hepatectomy for liver transplantation, for which we performed whole exome sequencing to investigate clonal expansion in PSC-involved bile ducts. Results: In total, 14 single cell-derived organoid lines were established from 2 patients with PSC and 3 control individuals. Based on the whole genome sequencing of those organoids, the number of mutations found in non-PSC bile duct epithelium increases with age at an annual mutation rate of 34.3 mutations per genome per year, which did not substantially differ from the rate in the PSC epithelium, suggesting that the inflammatory process in PSC hardly affected the mutations in PSC epithelium. To further investigate clonal expansion in the PSC epithelium, a total of 120 bulk organoid samples from perihilar bile ducts in 3 PSC patients and 111 LCM samples from intrahepatic bile ducts in 4 PSC patients were analyzed. In perihilar bile duct-derived organoids, we detected a median of 13 [1-30] somatic mutations per exome in samples derived from perihilar bile ducts and 20 [5-41] mutations per exome in those from intrahepatic LCM samples. Most mutations were detected in a single sample but some mutation clusters were shared by adjacent samples, which expanded in an area as large as 13 mm in length. Expanded clones harbored mutations in known cancer-driver genes, such as ARID1A and KRAS, which were enriched in segmental bile ducts, suggesting their role in the clonal expansion. Conclusions: Here, we established the method to detect somatic mutations accumulated in the normal/inflamed bile duct epithelium using an organoid-based analysis of clonal somatic mutations. Our results revealed clonal expansion existing in PSC epithelium and open up a way to the better understanding of carcinogenesis in the bile duct. Citation Format: Hirona Maeda, Nobuyuki Kakiuchi, Takashi Ito, Eri Ogawa, Masahiro Shiokawa, Norimitsu Uza, Hiroko Tanaka, Yasuhito Nannya, Hideki Makishima, Yuzo Kodama, Etsuro Hatano, Satoru Miyano, Seishi Ogawa. Clonal expansion in bile duct associated with chronic inflammation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1626.

Abstract 4004: Fine-tuning affinity/avidity of anti-CAIX CAR T cells to mitigate on-target off-tumor toxicity in clear cell renal cell carcinoma

Abstract On-target off-tumor toxicity (OTOT) is one of the major hurdles preventing tumor-associated antigen (TAA) targeted therapy from effectively treating patients with solid tumors due to the shared presence of the same TAA on normal tissues. We have previously demonstrated high expression of carbonic anhydrase IX (CAIX) in ccRCC patient samples and low-density expression on healthy bile duct epithelium. In 2006, a clinical trial was stopped due to OTOT bile duct toxicity observed in patients infused with anti-CAIX CAR T cell therapy. To address the issue of OTOT in the bile duct, we performed affinity/avidity fine-tuning of the anti-CAIX CAR G36 to specifically target ccRCC tumor cells with high CAIX expression while sparing cholangiocytes with low CAIX expression. We generated a complementarity-determining region (CDR) single variant mutagenesis library of G36 and displayed the library on yeast for screening. Using flow cytometry, we were able to identify six populations based on antigen-binding affinity: high, med-high, med, med-low, low, and loss of binding. These libraries were sequenced via PacBio, a next generation sequencing (NGS) platform that excels in long-read sequencing, providing a powerful tool to detect single mutations in the scFv. The results were analyzed to identify enriched mutations compared to the wild-type G36, and inspected using in silico modeling and docking. Furthermore, enriched mutants from med-low and low populations were tested in CAR-T format for their cytotoxic capacity on tumor cells and bile duct cholangiocytes, as well as their avidity. We demonstrate that mutations in CDR2 and CDR3 of the heavy chain successfully mitigate OTOT toxicity on cholangiocytes with physiological levels of CAIX expression while maintaining tumor-killing capacity, shedding light on CDR mutagenesis as a useful tool to mitigate OTOT toxicity. Citation Format: Stephen Hsien-Chi Yuan, Yufei Wang, Rabia Abbas, Peterson Mathenge, Charles Chien, Christian D. Coherd, Branson Bajoua, Matthew R. Chang, Nithyassree Murugan, Gabriella M. Kastrunes, Guilin Wang, Song-My Hoang, Wayne A. Marasco. Fine-tuning affinity/avidity of anti-CAIX CAR T cells to mitigate on-target off-tumor toxicity in clear cell renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4004.

Safety Parameters for the Use of Holmium:YAG Laser in the Treatment of Biliary Calculi: The Ex-Vivo Model.

Background and Objectives: While studies have demonstrated the efficacy of cholangioscopy-guided Holmium-Yttrium aluminum garnet (Ho:YAG) laser lithotripsy for the treatment of refractory bile duct stones, data regarding the safety of the operating parameters for laser lithotripsy are lacking. The aim of this study was to determine safe, yet effective, energy settings for Ho:YAG laser in the ex-vivo model. Materials and Methods: This ex vivo experimental study utilized the Ho:YAG laser on porcine bile duct epithelium and human gallstones. Ho:YAG laser lithotripsy was applied in different power settings from 8 to 15 Watts (W) to six explanted porcine bile ducts. Settings that appeared safe were then utilized to fragment seventy-three human gallstones. Results: The median bile duct perforation times with the Ho:YAG laser between 8-15 W were: >60 s (8 W); 23 s (9 W); 29 s (10 W); 27 s (12 W); 12 s (14 W); and 8 s (15 W). Statistically significant differences in the median perforation times were noted between 8 W vs. 15 W, 9 W vs. 15 W, 10 W vs. 15 W, and 12 W vs. 15 W (p < 0.05). When using a 365 µm Ho:YAG laser probe at 8-12 W, the fragmentation rates on various size stones were: 100% (<1.5 cm); 80-100% (1.6-2.0 cm) and 0-32% (>2.0 cm). Optimal fragmentation was seen utilizing 12 W with high energy (2.4 J) and low frequency (5 Hz) settings. Using a larger 550 µm probe at these settings resulted in 100% fragmentation of stones larger than 2 cm. Conclusions: The Ho:YAG laser appears to be safe and effective in the treatment of large bile duct stones when used between 8-12 W in 5 s bursts in an ex vivo model utilizing porcine bile ducts and human gallstones.

Igniting cold tumors of intrahepatic cholangiocarcinoma: An insight into immune evasion and tumor immune microenvironment

&lt;p&gt;Intrahepatic cholangiocarcinoma (ICC) is a rare hepatobiliary cancer that originates from the epithelium of the intrahepatic bile duct. The various treatments for ICC, such as chemotherapy, radiotherapy, and locoregional therapy, confer only modest improvements in survival rates. Immunotherapy, although revolutionary in cancer treatment, has found limited application in the treatment of ICCs due to the ��cold�� nature of these tumors, which is marked by scant T-cell infiltration. This characteristic makes immune checkpoint inhibitors (ICIs) unsuitable for the majority of ICC patients. Therefore, comprehensively understanding the mechanisms underlying these ��cold�� tumors is crucial for harnessing the potential of immunotherapy for treating ICC patients. This paper explores immune evasion mechanisms and the complex tumor immune microenvironment of ICC. This study provides a comprehensive overview of therapeutic strategies aimed at activating cold tumors and enhancing their immunogenicity. Furthermore, potential and promising targets for cancer vaccines and adoptive cellular therapy in the context of ICC are discussed. This endeavor strives to reveal new pathways for innovative immunotherapy strategies, with a focus on overcoming the key challenge of triggering an effective immune response in ICC patients.&lt;/p&gt;

The inhibition of YAP Signaling Prevents Chronic Biliary Fibrosis in the Abcb4-/- Model by Modulation of Hepatic Stellate Cell and Bile Duct Epithelium Cell Pathophysiology.

Primary sclerosing cholangitis (PSC) represents a chronic liver disease characterized by poor prognosis and lacking causal treatment options. Yes-associated protein (YAP) functions as a critical mediator of fibrogenesis; however, its therapeutic potential in chronic biliary diseases such as PSC remains unestablished. The objective of this study is to elucidate the possible significance of YAP inhibition in biliary fibrosis by examining the pathophysiology of hepatic stellate cells (HSC) and biliary epithelial cells (BEC). Human liver tissue samples from PSC patients were analyzed to assess the expression of YAP/connective tissue growth factor (CTGF) relative to non-fibrotic control samples. The pathophysiological relevance of YAP/CTGF in HSC and BEC was investigated in primary human HSC (phHSC), LX-2, H69, and TFK-1 cell lines through siRNA or pharmacological inhibition utilizing verteporfin (VP) and metformin (MF). The Abcb4-/- mouse model was employed to evaluate the protective effects of pharmacological YAP inhibition. Hanging droplet and 3D matrigel culture techniques were utilized to investigate YAP expression and activation status of phHSC under various physical conditions. YAP/CTGF upregulation was observed in PSC patients. Silencing YAP/CTGF led to inhibition of phHSC activation and reduced contractility of LX-2 cells, as well as suppression of epithelial-mesenchymal transition (EMT) in H69 cells and proliferation of TFK-1 cells. Pharmacological inhibition of YAP mitigated chronic liver fibrosis in vivo and diminished ductular reaction and EMT. YAP expression in phHSC was effectively modulated by altering extracellular stiffness, highlighting YAP's role as a mechanotransducer. In conclusion, YAP regulates the activation of HSC and EMT in BEC, thereby functioning as a checkpoint of fibrogenesis in chronic cholestasis. Both VP and MF demonstrate effectiveness as YAP inhibitors, capable of inhibiting biliary fibrosis. These findings suggest that VP and MF warrant further investigation as potential therapeutic options for the treatment of PSC.

Remodulatory effects of coral fossil on hematobiochemical parameters and histoaccumulation of specific organs in lead intoxicated broilers

ObjectivesThe research aims to assess the impact of coral fossil (CF) on hematobiochemical parameters, organ’s accumulation, and remodulation in lead (Pb) intoxicated broiler birds. Methods45 broilers were used in the experiment, which was divided into 03 groups, each of which contained 15 broilers. The control group was Group A. Pb (280 mg/kg b. w.) was administered orally to the birds in group B. Group C received Pb (280 mg/kg b.w.) and CF (1 gm/kg b.w.) oralsupplements. The research was carried out for 30 days. Blood samples were collected, and sera were prepared for biochemical analysis. Pb accumulation concentration was assessed in muscle, liver and kidney. Moreover, samples of the brain, liver, and kidneys were obtainedand prepared for histological analysis. ResultsPb affected hematological markers (Total RBC, Hb conc., hematocrit value, differential leukocytes and blood indices), which were restored with CF supplementation. In Pb-treated broilers, hepatic enzymes (AST, ALT), renal biomarkers (creatinine, total protein and albumin) and lipid profile (TC, TG, HDL and LDL)increased substantially (p < 0.05), but dropped significantly (p < 0.05)after CF supplementation. Pb accumulation was higher in liver, kidney and muscle tissue that was reduced by CF treatment. The histopathological study demonstrated that there was accumulation of fluid around in brain, hyperplasia of bile duct and glomerular epithelium in Pb intoxicated broilers and these were restored after CF supplementation. ConclusionsTherefore, it can be concluded that CF supplementation restored the lead induced detrimental effects on broilers. So, CF has remodulatory effects on Pb toxicity.