The self-limited nature of nodular fasciitis (NF) is well-known but its precise mechanism has not yet been clarified. We observed that "young" NF (preoperative duration <1 month) consistently ...contains a higher percentage (~80%) of USP6 break-apart FISH signals than "old" NF (preoperative duration >3 months) (~20%). Thus, we hypothesized that our original observation may reflect a connection with the self-limited nature of NF. Seventeen cases with reliable data concerning the onset were selected, thus approximating the lifetime of each tumor. Besides the USP6 interphase FISH examination, we also checked the most common MYH9-USP6 fusion using RT-PCR. Because of the known pathways of the tumorigenesis of NF, the mRNA level of USP6, TRAIL, IFN-beta, JAK1, STAT1, STAT3, JUN, and CDKN2A was measured using qRT-PCR. Regarding proteins, USP6, p16, p27, TRAIL, and IFN-beta were examined using immunohistochemistry. Targeted gene panel next-generation sequencing (NGS) of three cases was additionally performed. We found a strong negative correlation (p = 0.000) between the lifetime and percentage of USP6 break-apart signals and a strong positive relationship (p = 0.000) between USP6 break-apart signals and mitotic counts. Results of immunostainings, along with qRT-PCR results, favored the previously-suggested USP6-induced negative feedback mechanism through activation of TRAIL and IFN-beta, likely resulting in apoptosis and senescence of tumor cells harboring USP6 fusions. Targeted-NGS resulted in the detection of several variants, but no additional recurrent changes in the pathogenesis of these tumors. We revealed on a cellular level the USP6-induced negative feedback mechanism. In conclusion, we emphasize that in "old" NF, the percentage of USP6 break-apart FISH signals can be as low as 14-27% which can be very important from a differential diagnostic point of view. We emphasize that a careful examination and interpretation of the NGS data is needed before clinical decision-making on treatment.
It is known that V-set and immunoglobulin domain containing 1 (VSIG1) is a cell–cell adhesion molecule that can serve as an indicator of better survival in patients with gastric cancer. Its ...interaction with cytoplasmic thyroid transcription factor 1 (TTF-1) has been hypothesized to characterize gastric-type HCC, but its clinical importance is far from understood. As VSIG1 has also been supposed to be involved in the epithelial–mesenchymal transition (EMT) phenomenon, we checked for the first time in the literature the supposed interaction between VSIG1, TTF-1, and Vimentin (VIM) in HCCs. Immunohistochemical (IHC) stains were performed on 217 paraffin-embedded tissue samples that included tumor cells and normal hepatocytes, which served as positive internal controls. VSIG1 positivity was seen in 113 cases (52.07%). In 71 out of 217 HCCs (32.71%), simultaneous positivity for VSIG1 and TTF-1 was seen, being more specific for G1/G2 carcinomas with a trabecular architecture and a longer OS (p = 0.004). A negative association with VIM was revealed (p < 0.0001). Scirrhous-type HCC proved negative for all three examined markers. The present paper validates the hypothesis of the existence of a gastric-type HCC, which shows a glandular-like architecture and is characterized by double positivity for VSIG1 and TTF-1, vimentin negativity, and a significant OS.
Background and Aim
Massive hepatic necrosis is a rare but often fatal complication of various liver injuries. Nevertheless, some patients can survive by spontaneous hepatic regeneration. It is known ...that surviving hepatocytes and/or progenitor cells can participate in this process but the mechanism of hepatic recovery is vague.
Methods
We examined 13 explanted human livers removed for acute liver failure. Combined immunohistochemistry, digital image analysis, and three‐dimensional reconstruction of serial sections were applied.
Results
Two patterns of regeneration could be distinguished. In livers with centrilobular necrosis, the surviving injured periportal hepatocytes started to proliferate and arrange into acinar structures and expressed α‐fetoprotein. If the injury wiped out almost all hepatocytes, large areas of parenchymal loss were invaded by an intense ductular reaction. The cells at the distal pole of the ductules differentiated into hepatocytes and formed foci organized by the branches of the portal vein. The expanding foci often containing complete portal triads were arranged around surviving central veins. Their fusion eventually could be an attempt to re‐establish the hepatic lobules.
Conclusions
Regeneration of human livers following massive hepatic necrosis can occur in two ways—either through proliferation of α‐fetoprotein‐positive acinary‐arranged hepatocytes or through ductular progenitor cells, with the latter being less efficient. Further investigation of these regenerative pathways may help identify biomarkers for likelihood of complete regeneration and hence have therapeutic implications.
Ductular reaction is a standard component of fibrotic liver tissue but its function is largely unknown. It is supposed to interact with the matrix producing myofibroblasts and compensate the ...declining regenerative capacity of hepatocytes. The relationship between the extent of fibrosis-ductular reaction, proliferative activity of hepatocytes and ductular reaction were studied sequentially in experimental hepatic fibrosis models.
Liver fibrosis/cirrhosis was induced in wild type and TGFβ overproducing transgenic mice by carbon tetrachloride and thioacetamide administration. The effect of thioacetamide was modulated by treatment with imatinib and erlotinib. The extent of ductular reaction and fibrosis was measured by morphometry following cytokeratin 19 immunofluorescent labeling and Picro Sirius staining respectively. The proliferative activity of hepatocytes and ductular reaction was evaluated by BrdU incorporation. The temporal distribution of the parameters was followed and compared within and between different experimental groups.
There was a strong significant correlation between the extent of fibrosis and ductular reaction in each experimental group. Although imatinib and erlotinib temporarily decreased fibrosis this effect later disappeared. We could not observe negative correlation between the proliferation of hepatocytes and ductular reaction in any of the investigated models.
The stringent connection between ductular reaction and fibrosis, which cannot be influenced by any of our treatment regimens, suggests that there is a close mutual interaction between them instead of a unidirectional causal relationship. Our results confirm a close connection between DR and fibrogenesis. However, since the two parameters changed together we could not establish a causal relationship and were unable to reveal which was the primary event. The lack of inverse correlation between the proliferation of hepatocytes and ductular reaction questions that ductular reaction can compensate for the failing regenerative activity of hepatocytes. No evidences support the persistent antifibrotic property of imatinib or erlotinib.
Chronic liver diseases have both high incidence and mortality rates; therefore, a deeper understanding of the underlying molecular mechanisms is essential. We have determined the content and ...sulfation pattern of chondroitin sulfate (CS) and heparan sulfate (HS) in human hepatocellular carcinoma and cirrhotic liver tissues, considering the etiology of the diseases. A variety of pathological conditions such as alcoholic liver disease, hepatitis B and C virus infections, and primary sclerosing cholangitis were studied. Major differences were observed in the total abundance and sulfation pattern of CS and HS chains. For example, the
6-O-
sulfation of CS is fundamentally different regarding etiologies of cirrhosis, and a 2–threefold increase in HS
N-
sulfation/
O-
sulfation ratio was observed in hepatocellular carcinoma compared to cirrhotic tissues.
Graphical abstract
The liver is well known for its enormous regenerative capacity. If the hepatocytes are compromised the reserve stem cells can regrow the lost tissue by means of oval cells differentiating into ...hepatocytes. We were curious whether this standby system was able to compensate for ontogenic liver growth arrested by 2-acetylaminofluorene (AAF) treatment or if it can be influenced by cholic acid, known to promote liver growth in several reactions.
(i) Four weeks-old (60-70g) male F344 rats were kept on standard chow and treated with solvent only, (ii) others were kept on 0,2% cholic acid (CA) enriched diet, (iii) treated with AAF, or (iiii) given a combination of CA diet and AAF treatment (AAF/CA). The proliferative response of epithelial cells was characterized by pulse bromodeoxyuridine labelling. The relative gene expression levels of senescence-related factors and bile acid receptors were determined by quantitative real-time polymerase chain reaction analysis.
AAF administration efficiently inhibited the physiological proliferation of hepatocytes in young, male F344 rats after weaning. The activation of stem cells was indicated by the increased proliferation of periportal biliary/oval cells (B/OC). If the rats were fed additionally by cholic acid enriched diet, typical oval cell reaction emerged, subsequently the oval cells differentiated into hepatocytes restituting liver growth. This reaction was mediated by increased production of HGF, IL-6 and SCF by the damaged liver. Moreover, upregulation of FXR expression on B/OC made them competent for bile acids. Our results indicate that endogenous, autocrine mechanisms involved in liver ontogeny are also able to activate the backup regenerative machinery of stem cells.
The extracellular matrix proteoglycan SPOCK1 is increasingly recognized as a contributor to the development and progression of cancers. Here, we study how SPOCK1, which is present in non-tumorous ...hepatocytes at low concentrations, promotes the development and progression of malignant hepatocellular tumors. Although SPOCK1 is an extracellular matrix proteoglycan, its concentration increases in the cytoplasm of hepatocytes starting with very low expression in the normal cells and then appearing in much higher quantities in cells of cirrhotic human liver and hepatocellular carcinoma. This observation is similar to that observed after diethylnitrosamine induction of mouse hepatocarcinogenesis. Furthermore, syndecan-1, the major proteoglycan of the liver, and SPOCK1 are in inverse correlation in the course of these events. In hepatoma cell lines, the cytoplasmic SPOCK1 colocalized with mitochondrial markers, such as MitoTracker and TOMM20, a characteristic protein of the outer membrane of the mitochondrion and could be detected in the cell nucleus. SPOCK1 downregulation of hepatoma cell lines by siRNA inhibited cell proliferation, upregulated p21 and p27, and interfered with pAkt and CDK4 expression. A tyrosine kinase array revealed that inhibition of SPOCK1 in the liver cancer cells altered MAPK signaling and downregulated several members of the Sarc family, all related to the aggressivity of the hepatoma cell lines. These studies support the idea that SPOCK1 enhancement in the liver is an active contributor to human and rodent hepatocarcinogenesis and cancer progression. However, its mitochondrial localization raises the possibility that it has a currently unidentified physiological function in normal hepatocytes.
Pancreatic neuroendocrine neoplasms pose a growing clinical challenge due to their rising incidence and variable prognosis. The current study aims to investigate microRNAs (miRNA; miR) as potential ...biomarkers for distinguishing between grade 1 (G1) and grade 2 (G2) pancreatic neuroendocrine tumors (PanNET). A total of 33 formalin-fixed, paraffin-embedded samples were analyzed, comprising 17 G1 and 16 G2 tumors. Initially, literature-based miRNAs were validated via real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR), confirming significant downregulation of miR-130b-3p and miR-106b in G2 samples. Through next-generation sequencing, we have identified and selected the top six miRNAs showing the highest difference between G1 and G2 tumors, which were further validated. RT-qPCR validation confirmed the downregulation of miR-30d-5p in G2 tumors. miRNA combinations were created to distinguish between the two PanNET grades. The highest diagnostic performance in distinguishing between G1 and G2 PanNETs by a machine learning algorithm was achieved when using the combination miR-106b + miR-130b-3p + miR-127-3p + miR-129-5p + miR-30d-5p. The ROC analysis resulted in a sensitivity of 83.33% and a specificity of 87.5%. The findings underscore the potential use of miRNAs as biomarkers for stratifying PanNET grades, though further research is warranted to enhance diagnostic accuracy and clinical utility.
Oncogenic K‐RAS has been difficult to target and currently there is no K‐RAS‐based targeted therapy available for patients suffering from K‐RAS‐driven lung adenocarcinoma (AC). Alternatively, ...targeting K‐RAS‐downstream effectors, K‐RAS‐cooperating signaling pathways or cancer hallmarks, such as tumor‐promoting inflammation, has been shown to be a promising therapeutic strategy. Since the JAK–STAT pathway is considered to be a central player in inflammation‐mediated tumorigenesis, we investigated here the implication of JAK–STAT signaling and the therapeutic potential of JAK1/2 inhibition in K‐RAS‐driven lung AC. Our data showed that JAK1 and JAK2 are activated in human lung AC and that increased activation of JAK–STAT signaling correlated with disease progression and K‐RAS activity in human lung AC. Accordingly, administration of the JAK1/2 selective tyrosine kinase inhibitor ruxolitinib reduced proliferation of tumor cells and effectively reduced tumor progression in immunodeficient and immunocompetent mouse models of K‐RAS‐driven lung AC. Notably, JAK1/2 inhibition led to the establishment of an antitumorigenic tumor microenvironment, characterized by decreased levels of tumor‐promoting chemokines and cytokines and reduced numbers of infiltrating myeloid derived suppressor cells, thereby impairing tumor growth. Taken together, we identified JAK1/2 inhibition as promising therapy for K‐RAS‐driven lung AC.
What's new?
A drug that inhibits the JAK–STAT pathway may score a hit against K‐RAS driven lung cancer. Here, the authors Investigated the JAK STAT pathway as a possible target in lung adenocarcinoma because of its role in inflammation‐mediated tumorigenesis. First, they showed that JAK1 and JAK2 are both activated in lung adenocarcinoma patients with oncogenic mutations in K‐RAS. Next, they treated the tumors with ruxolitinib, which inhibits JAK1/2. The drug successfully slowed tumor proliferation and progression in immunocompetent mouse models. Furthermore, treatment with ruxolitinib reduced the tumor‐promoting factors present in the microenvironment.
Abstract
Alterations in mTOR signalling molecules, including
RICTOR
amplification, have been previously described in many cancers, particularly associated with poor prognosis. In this study,
RICTOR
...copy number variation (CNV) results of diagnostic next-generation sequencing (NGS) were analysed in 420 various human malignant tissues.
RICTOR
amplification was tested by Droplet Digital PCR (ddPCR) and validated using the “gold standard” fluorescence in situ hybridisation (FISH). Additionally, the consequences of Rictor protein expression were also studied by immunohistochemistry.
RICTOR
amplification was presumed in 37 cases with CNV ≥ 3 by NGS, among these, 16 cases (16/420; 3.8%) could be validated by FISH, however, ddPCR confirmed only 11
RICTOR
-amplified cases with lower sensitivity. Based on these, neither NGS nor ddPCR could replace traditional FISH in proof of
RICTOR
amplification. However, NGS could be beneficial to highlight potential
RICTOR
-amplified cases. The obtained results of the 14 different tumour types with FISH-validated
RICTOR
amplification demonstrate the importance of
RICTOR
amplification in a broad spectrum of tumours. The newly described
RICTOR
-amplified entities could initiate further collaborative studies with larger cohorts to analyse the prevalence of
RICTOR
amplification in rare diseases. Finally, our and further work could help to improve and expand future therapeutic opportunities for mTOR-targeted therapies.
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