A potential player in pathogenesis
Article Type
Changed
Wed, 01/04/2023 - 14:36

An investigation of genomics data related to primary sclerosing cholangitis (PSC) in published medical literature revealed several genes likely involved in the pathogenesis of this autoimmune diseases, according to a study published in Gastro Hep Advances.

PSC is very rare, with an incidence of 0-1.3 cases per 100,000 people per year. Because up to 80% of patients with PSC also have inflammatory bowel disease (IBD), a link along the gut-liver axis is suspected. So far, scientists have not understood the causes of PSC, the main complications of which include biliary cirrhosis, bacterial cholangitis, and cholangiocarcinoma.

No treatment is currently available for PSC, but the findings of this genomics study suggest several targets that may be worth pursuing, particularly the gene NR0B2.

“The therapeutic targeting of NR0B2 may potentiate that of FXR [farnesoid X receptor] and enable action on early events of the disease and prevent its progression,” wrote Christophe Desterke, PhD, of the Paul-Brousse Hospital, the French National Institute of Health and Medical Research, and the University of Paris-Saclay in Villejuif, France, and his associates.

The researchers used an algorithmic tool to mine the MEDLINE/PubMed/NCBI database using the three key symptoms of PSC – biliary fibrosis, biliary inflammation, and biliary stasis – as their keywords. This approach allowed them to discover the genes and potential pathways related to PSC in published research text or in clinical, animal, and cellular models.

The researchers initially found 525 genes linked to PSC and then compared them to RNA data from liver biopsies taken from patients with liver disease from various causes. This process led to a ranking of the 10 best markers of PSC, based on the data-mining method and the genes’ association with one or more of the three PSC symptoms.

At the top of the list is NR1H4, also called FXR, which ranks most highly with biliary fibrosis and biliary stasis. NR1H4 is already a clear target for cholestatic and fatty liver diseases, the authors noted. The other genes, in descending order of relevance, are: ABCB4, ABCB11, TGFB1, IFNL3, PNPLA3, IL6, TLR4, GPBAR1, and IL17A. In addition, complications of PSC were significantly associated with upregulation of TNFRS12A, SOX9, ANXA2, MMP7, and LCN2.

Separately, investigation of the 525 initially identified genes in mouse models of PSC revealed that NR0B2 is also a key player in the pathogenesis of PSC.

"NR0B2 was upregulated in PSC livers independent of gender, age, and body mass index,” the authors reported. “Importantly, it was not dependent on the severity of PSC in the prognostic cohort, suggesting that this may be an early event during the disease.”

The researchers also found a possible pathway explaining the autoimmunity of PSC – the involvement of CD274, also known as the PDL1 immune checkpoint. The authors noted that the PDL1 inhibitor pembrolizumab has previously been reported as a cause of sclerosing cholangitis.

Further, the researchers discovered overexpression of FOXP3 in the livers of patients with PSC. Because FOXP3 determines what T-cell subtypes look like, the finding suggests that an “imbalance between Foxp3þ regulatory T cells and Th17 cells may be involved in IBD and PSC,” they wrote.

Also of note was the overexpression of SOX9 in the livers of patients with PSC whose profiles suggested the worst clinical prognoses.

Finally, the researchers identified three genes as potentially involved in development of cholangiocarcinoma: GSTA3, ID2 (which is overexpressed in biliary tract cancer), and especially TMEM45A, a protein in cells’ Golgi apparatus that is already known to be involved in the development of several other cancers.

The research was funded by the French National Institute of Health and Medical Research. The authors reported no conflicts of interest.

Body

Primary sclerosing cholangitis (PSC) is a bile duct disease with few therapeutic options other than liver transplant, and thus its prognosis remains grim. Additionally, the factors that cause the disease are not well understood. Identifying the pathways and genes involved in PSC pathogenesis could help in the development of potential therapeutic targets.

Dr. Kari Nejak-Bowen

In this report Desterke et al. mined public data sets to identify and define a PSC-specific network. Of the top genes in this list, NR0B2 stood out as a potential player in pathogenesis because of its involvement in regulating bile acid metabolism. The authors showed that upregulation of NR0B2 occurs early in the disease process and in patient tissues is independent of variables such as gender and sex. Interestingly, the authors showed that this upregulation occurs primarily in cholangiocytes, the cells lining the bile duct. Higher expression of NR0B2 results in reprogramming that alters the metabolic function of these cells and predisposes them to malignancy.

This study, which is the first to look at omics data for PSC, highlights the involvement of genes and pathways that were previously unrecognized in disease pathogenesis. By using data derived from human PSC liver biopsies and animal models of PSC, the authors were able to validate their findings across species, which strengthened their conclusions. This approach also showed that NR0B2 deregulation occurs primarily in cholangiocytes, suggesting that future therapies should be targeted to this cell type. These important findings will improve our understanding of this rare but clinically significant disease.

Kari Nejak-Bowen, PhD, MBA, is associate professor, department of pathology, University of Pittsburgh School of Medicine. She has no relevant conflicts of interest.

Publications
Topics
Sections
Body

Primary sclerosing cholangitis (PSC) is a bile duct disease with few therapeutic options other than liver transplant, and thus its prognosis remains grim. Additionally, the factors that cause the disease are not well understood. Identifying the pathways and genes involved in PSC pathogenesis could help in the development of potential therapeutic targets.

Dr. Kari Nejak-Bowen

In this report Desterke et al. mined public data sets to identify and define a PSC-specific network. Of the top genes in this list, NR0B2 stood out as a potential player in pathogenesis because of its involvement in regulating bile acid metabolism. The authors showed that upregulation of NR0B2 occurs early in the disease process and in patient tissues is independent of variables such as gender and sex. Interestingly, the authors showed that this upregulation occurs primarily in cholangiocytes, the cells lining the bile duct. Higher expression of NR0B2 results in reprogramming that alters the metabolic function of these cells and predisposes them to malignancy.

This study, which is the first to look at omics data for PSC, highlights the involvement of genes and pathways that were previously unrecognized in disease pathogenesis. By using data derived from human PSC liver biopsies and animal models of PSC, the authors were able to validate their findings across species, which strengthened their conclusions. This approach also showed that NR0B2 deregulation occurs primarily in cholangiocytes, suggesting that future therapies should be targeted to this cell type. These important findings will improve our understanding of this rare but clinically significant disease.

Kari Nejak-Bowen, PhD, MBA, is associate professor, department of pathology, University of Pittsburgh School of Medicine. She has no relevant conflicts of interest.

Body

Primary sclerosing cholangitis (PSC) is a bile duct disease with few therapeutic options other than liver transplant, and thus its prognosis remains grim. Additionally, the factors that cause the disease are not well understood. Identifying the pathways and genes involved in PSC pathogenesis could help in the development of potential therapeutic targets.

Dr. Kari Nejak-Bowen

In this report Desterke et al. mined public data sets to identify and define a PSC-specific network. Of the top genes in this list, NR0B2 stood out as a potential player in pathogenesis because of its involvement in regulating bile acid metabolism. The authors showed that upregulation of NR0B2 occurs early in the disease process and in patient tissues is independent of variables such as gender and sex. Interestingly, the authors showed that this upregulation occurs primarily in cholangiocytes, the cells lining the bile duct. Higher expression of NR0B2 results in reprogramming that alters the metabolic function of these cells and predisposes them to malignancy.

This study, which is the first to look at omics data for PSC, highlights the involvement of genes and pathways that were previously unrecognized in disease pathogenesis. By using data derived from human PSC liver biopsies and animal models of PSC, the authors were able to validate their findings across species, which strengthened their conclusions. This approach also showed that NR0B2 deregulation occurs primarily in cholangiocytes, suggesting that future therapies should be targeted to this cell type. These important findings will improve our understanding of this rare but clinically significant disease.

Kari Nejak-Bowen, PhD, MBA, is associate professor, department of pathology, University of Pittsburgh School of Medicine. She has no relevant conflicts of interest.

Title
A potential player in pathogenesis
A potential player in pathogenesis

An investigation of genomics data related to primary sclerosing cholangitis (PSC) in published medical literature revealed several genes likely involved in the pathogenesis of this autoimmune diseases, according to a study published in Gastro Hep Advances.

PSC is very rare, with an incidence of 0-1.3 cases per 100,000 people per year. Because up to 80% of patients with PSC also have inflammatory bowel disease (IBD), a link along the gut-liver axis is suspected. So far, scientists have not understood the causes of PSC, the main complications of which include biliary cirrhosis, bacterial cholangitis, and cholangiocarcinoma.

No treatment is currently available for PSC, but the findings of this genomics study suggest several targets that may be worth pursuing, particularly the gene NR0B2.

“The therapeutic targeting of NR0B2 may potentiate that of FXR [farnesoid X receptor] and enable action on early events of the disease and prevent its progression,” wrote Christophe Desterke, PhD, of the Paul-Brousse Hospital, the French National Institute of Health and Medical Research, and the University of Paris-Saclay in Villejuif, France, and his associates.

The researchers used an algorithmic tool to mine the MEDLINE/PubMed/NCBI database using the three key symptoms of PSC – biliary fibrosis, biliary inflammation, and biliary stasis – as their keywords. This approach allowed them to discover the genes and potential pathways related to PSC in published research text or in clinical, animal, and cellular models.

The researchers initially found 525 genes linked to PSC and then compared them to RNA data from liver biopsies taken from patients with liver disease from various causes. This process led to a ranking of the 10 best markers of PSC, based on the data-mining method and the genes’ association with one or more of the three PSC symptoms.

At the top of the list is NR1H4, also called FXR, which ranks most highly with biliary fibrosis and biliary stasis. NR1H4 is already a clear target for cholestatic and fatty liver diseases, the authors noted. The other genes, in descending order of relevance, are: ABCB4, ABCB11, TGFB1, IFNL3, PNPLA3, IL6, TLR4, GPBAR1, and IL17A. In addition, complications of PSC were significantly associated with upregulation of TNFRS12A, SOX9, ANXA2, MMP7, and LCN2.

Separately, investigation of the 525 initially identified genes in mouse models of PSC revealed that NR0B2 is also a key player in the pathogenesis of PSC.

"NR0B2 was upregulated in PSC livers independent of gender, age, and body mass index,” the authors reported. “Importantly, it was not dependent on the severity of PSC in the prognostic cohort, suggesting that this may be an early event during the disease.”

The researchers also found a possible pathway explaining the autoimmunity of PSC – the involvement of CD274, also known as the PDL1 immune checkpoint. The authors noted that the PDL1 inhibitor pembrolizumab has previously been reported as a cause of sclerosing cholangitis.

Further, the researchers discovered overexpression of FOXP3 in the livers of patients with PSC. Because FOXP3 determines what T-cell subtypes look like, the finding suggests that an “imbalance between Foxp3þ regulatory T cells and Th17 cells may be involved in IBD and PSC,” they wrote.

Also of note was the overexpression of SOX9 in the livers of patients with PSC whose profiles suggested the worst clinical prognoses.

Finally, the researchers identified three genes as potentially involved in development of cholangiocarcinoma: GSTA3, ID2 (which is overexpressed in biliary tract cancer), and especially TMEM45A, a protein in cells’ Golgi apparatus that is already known to be involved in the development of several other cancers.

The research was funded by the French National Institute of Health and Medical Research. The authors reported no conflicts of interest.

An investigation of genomics data related to primary sclerosing cholangitis (PSC) in published medical literature revealed several genes likely involved in the pathogenesis of this autoimmune diseases, according to a study published in Gastro Hep Advances.

PSC is very rare, with an incidence of 0-1.3 cases per 100,000 people per year. Because up to 80% of patients with PSC also have inflammatory bowel disease (IBD), a link along the gut-liver axis is suspected. So far, scientists have not understood the causes of PSC, the main complications of which include biliary cirrhosis, bacterial cholangitis, and cholangiocarcinoma.

No treatment is currently available for PSC, but the findings of this genomics study suggest several targets that may be worth pursuing, particularly the gene NR0B2.

“The therapeutic targeting of NR0B2 may potentiate that of FXR [farnesoid X receptor] and enable action on early events of the disease and prevent its progression,” wrote Christophe Desterke, PhD, of the Paul-Brousse Hospital, the French National Institute of Health and Medical Research, and the University of Paris-Saclay in Villejuif, France, and his associates.

The researchers used an algorithmic tool to mine the MEDLINE/PubMed/NCBI database using the three key symptoms of PSC – biliary fibrosis, biliary inflammation, and biliary stasis – as their keywords. This approach allowed them to discover the genes and potential pathways related to PSC in published research text or in clinical, animal, and cellular models.

The researchers initially found 525 genes linked to PSC and then compared them to RNA data from liver biopsies taken from patients with liver disease from various causes. This process led to a ranking of the 10 best markers of PSC, based on the data-mining method and the genes’ association with one or more of the three PSC symptoms.

At the top of the list is NR1H4, also called FXR, which ranks most highly with biliary fibrosis and biliary stasis. NR1H4 is already a clear target for cholestatic and fatty liver diseases, the authors noted. The other genes, in descending order of relevance, are: ABCB4, ABCB11, TGFB1, IFNL3, PNPLA3, IL6, TLR4, GPBAR1, and IL17A. In addition, complications of PSC were significantly associated with upregulation of TNFRS12A, SOX9, ANXA2, MMP7, and LCN2.

Separately, investigation of the 525 initially identified genes in mouse models of PSC revealed that NR0B2 is also a key player in the pathogenesis of PSC.

"NR0B2 was upregulated in PSC livers independent of gender, age, and body mass index,” the authors reported. “Importantly, it was not dependent on the severity of PSC in the prognostic cohort, suggesting that this may be an early event during the disease.”

The researchers also found a possible pathway explaining the autoimmunity of PSC – the involvement of CD274, also known as the PDL1 immune checkpoint. The authors noted that the PDL1 inhibitor pembrolizumab has previously been reported as a cause of sclerosing cholangitis.

Further, the researchers discovered overexpression of FOXP3 in the livers of patients with PSC. Because FOXP3 determines what T-cell subtypes look like, the finding suggests that an “imbalance between Foxp3þ regulatory T cells and Th17 cells may be involved in IBD and PSC,” they wrote.

Also of note was the overexpression of SOX9 in the livers of patients with PSC whose profiles suggested the worst clinical prognoses.

Finally, the researchers identified three genes as potentially involved in development of cholangiocarcinoma: GSTA3, ID2 (which is overexpressed in biliary tract cancer), and especially TMEM45A, a protein in cells’ Golgi apparatus that is already known to be involved in the development of several other cancers.

The research was funded by the French National Institute of Health and Medical Research. The authors reported no conflicts of interest.

Publications
Publications
Topics
Article Type
Sections
Article Source

FROM GASTRO HEP ADVANCES

Disallow All Ads
Content Gating
No Gating (article Unlocked/Free)
Alternative CME
Disqus Comments
Default
Use ProPublica
Hide sidebar & use full width
render the right sidebar.
Conference Recap Checkbox
Not Conference Recap
Clinical Edge
Display the Slideshow in this Article
Medscape Article
Display survey writer
Reuters content
Disable Inline Native ads
WebMD Article