Gen-Sheng Feng

Abbreviations: CTLA-4, cytotoxic T lymphocytes antigen-4; ICBs, immune checkpoint blockades; MAIT, mucosal-associated invariant T; Mrc1, mannose receptor C-type 1; PD-1, programmed cell death protein 1; TME, tumor microenvironment.

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death without effective treatment. Oncogenic drivers, including PTPN11/Shp2, Ikkβ kinase (IKK), c-Met and β-catenin, as well as tumor microenvironment as illustrated by a carcinogen or diethylnitrosamine (DEN)-treated models, have combined contribution to cancer progression that have distinct prevalence in human HCC progression. We previously found that disruption of Ras/Erk by Shp2 deletion combined with deletion of NF-κB unexpectedly dysregulated circadian clock genes which leads to further cancer progression. Except for this, limited reports investigated how various other oncogenic genes aberration would incorporate with DEN to induce HCC. Further, no reports investigated the dynamic evolution of transcriptomic aberration incorporating genetic changes and the differential functional pathways involved in DEN plus …

The incidence of nonalcoholic fatty liver disease (NAFLD) is increasing rapidly worldwide and causes a significant public health issue. The global prevalence of NAFLD is approximately 25%, ranging from 13% in Africa to 42% in Southeast Asia. 1 Nonalcoholic steatohepatitis (NASH) shows a more aggressive manifestation of NAFLD and can progress to cirrhosis and hepatocellular carcinoma (HCC). 2 The annual incidences of HCC in cohorts of patients with NASH in the United States and Europe range from 0.7% to 2.6%. 1 Many factors affect the progression from NASH to NASH-related HCC, such as hormones, the gut microbiota, and the immune microenvironment. 3 Substantial studies have shown that innate and adaptive immune mechanisms are involved in promoting hepatic inflammation in NASH. 3 Resident macrophages (Kupffer cells) and recruited monocytes/macrophages play a crucial role in the …

Abstract CD133 (prominin 1) is widely viewed as a cancer stem cell marker in association with drug resistance and cancer recurrence. Herein, we report that with impaired RTK-Shp2-Ras-Erk signaling, heterogenous hepatocytes form clusters that manage to divide during mouse liver regeneration. These hepatocytes are characterized by upregulated CD133 while negative for other progenitor cell markers. Pharmaceutical inhibition of proliferative signaling also induced CD133 expression in various cancer cell types from multiple animal species, suggesting an inherent and common mechanism of stress response. Super-resolution and electron microscopy localize CD133 on intracellular vesicles that apparently migrate between cells, which we name ‘intercellsome.’Isolated CD133+ intercellsomes are enriched with mRNAs rather than miRNAs. Single-cell RNA sequencing reveals lower intracellular diversity (entropy) of mitogenic mRNAs in Shp2-deficient cells, which may be remedied by intercellular mRNA exchanges between CD133+ cells. CD133-deficient cells are more sensitive to proliferative signal inhibition in livers and intestinal organoids. These data suggest a mechanism of intercellular communication to compensate for intracellular signal deficit in various cell types. eLife assessmentThis important study was designed to examine the bypass of Ras/Erk signaling defects that enable limited regeneration in a mouse model of hepatic regeneration. This hepatocyte proliferation is associated with the expression by groups of cells of mRNA-loaded CD133+ intracellular vesicles that mediate an intercellular signaling pathway that supports …

ConclusionsThese results unveil complex mechanisms for the tumor‐suppressing effect of pharmaceutical Shp2 inhibition in the liver immune environment. We provide a proof of principle for clinical trials with specific Shp2 inhibitors in patients with primary and metastasized liver cancer.

Objective:Immunotherapy with immune checkpoint inhibitors (ICIs) has become a standard of care for many malignancies. The tumor microenvironment (TME) varies across different organs and affects tumor initiation, progression, and treatment outcomes. Organ-specific differential responses to ICIs have been observed in various cancers. The underlying mechanisms warrant further investigation.Data Sources and Study Selection:We enrolled relevant clinical and preclinical studies conducted by our groups and others. Current evidence and data were reviewed and future implication was discussed.Results:In patients with advanced hepatocellular carcinoma or esophageal cancer, non-small cell lung cancer, or melanoma with liver metastases, the efficacy of ICI-based therapy was generally lower in the liver than in other organs. The mouse liver cancer study showed that myeloid-derived suppressor cells (MDSCs …

Background & AimsComplex communications between hepatocytes and Kupffer cells (KCs) are known to drive or suppress hepatocarcinogenesis, with controversial data in the literature. In previous experiments that aimed to decipher hepatocyte/KC interactions, we unexpectedly unveiled a tumor-suppressing effect of polyinosinic-polycytidylic acid, a widely used inducer of MX dynamin like GTPase 1 (Mx1)-cre expression, which questioned a theory of interleukin 1a/6 cytokine circuit in hepatocyte/KC communication. The goal of this study was to clarify the controversy and decipher unique functions of KCs and non-KC macrophages in liver tumorigenesis.MethodsWe used the C-type lectin domain family 4 member F (Clec4f)-cre system to delete Src-homology 2 domain-containing tyrosine phosphatase 2 (Shp2)/protein tyrosine phosphatase nonreceptor 11 (Ptpn11) in KCs, and a combination of Clec4f-cre and …

The nonreceptor tyrosine phosphatase SHP2 has been at the center of cell signaling research for three decades. SHP2 is required to fully activate the RTK/RAS/ERK signaling cascade, although the underlying mechanisms are not completely understood. PTPN11, which encodes SHP2, is the first identified proto-oncogene that encodes a tyrosine phosphatase, with dominantly activating mutations detected in leukemias and solid tumors. However, SHP2 has pro- and antioncogenic effects, and the most recent data reveal opposite activities of SHP2 in tumor cells and microenvironment cells. Allosteric SHP2 inhibitors show promising antitumor effects and overcome resistance to inhibitors of RAS/ERK signaling in animal models. Many clinical trials with orally bioactive SHP2 inhibitors, alone or combined with other regimens, are ongoing for a variety of cancers worldwide, with therapeutic outcomes yet unknown. This …

Nonalcoholic steatohepatitis (NASH) is a chronic liver disease, an aggressive form of nonalcoholic fatty liver disease (NAFLD) by the mixture of liver inflammation, steatosis, and fibrosis, that is becoming a leading cause of liver-related morbidity and mortality worldwide. 1 To reach the stage of NASH from simple steatosis, the immune cell-mediated inflammatory process is considered as a major step. 1 Since their discovery in 1876, Kupffer cells (KCs) have been identified as liver resident macrophages to preserve tissue homeostasis. 2 KCs are originated from yolk sac–derived progenitor cells, while monocyte-derived macrophages are also recruited into the liver from peripheral blood. It remains to be determined which group of macrophages is a major contributing cell type in NASH progression and what the underlying molecular mechanism is. Macrophages are functionally dynamic with levels of plasticity. Under …

The timely onset of female parturition is a critical determinant for pregnancy success. The highly heterogenous maternal decidua has been increasingly recognized as a vital factor in setting the timing of labor. Despite the cell type specific roles in parturition, the role of the uterine epithelium in the decidua remains poorly understood. This study uncovers the critical role of epithelial SHP2 in parturition initiation via COX1 and COX2 derived PGF2α leveraging epithelial specific Shp2 knockout mice, whose disruption contributes to delayed parturition initiation, dystocia and fetal deaths. Additionally, we also show that there are distinct types of epithelium in the decidua approaching parturition at single cell resolution accompanied with profound epithelium reformation via proliferation. Meanwhile, the epithelium maintains the microenvironment by communicating with stromal cells and macrophages. The epithelial …

ConclusionsThe poor response of liver cancers to αPD‐L1 therapy is largely attributable to a unique hepatic immunotolerant microenvironment, independent of tumor origins or types. The success of a combinatorial immunotherapy relies on coordinated inhibition or activation of various innate and adaptive immune cell activities.

In mammals, the growth and maturation of oocytes within growing follicles largely depends on ovarian granulosa cells (GCs) in response to gonadotropin stimulation. Many signals have been shown to regulate GC proliferation and apoptosis. However, whether the tyrosine phosphatase SHP2 is involved remains unclear. In this study, we identified the crucial roles of SHP2 in modulating GC proliferation and apoptosis. The production of both mature oocytes and pups was increased in mice with Shp2 specifically deleted in ovarian GCs via Fshr-Cre. Shp2 deletion simultaneously promoted GC proliferation and inhibited GC apoptosis. Furthermore, Shp2 deficiency promoted, while Shp2 overexpression inhibited, the proliferation of cultured primary mouse ovarian GCs and the human ovarian granulosa-like tumor cell line KGN in vitro. Shp2 deficiency promoted follicule-stimulating hormone (FSH)-activated …

The Ras/Erk and NF-κB pathways play critical roles in cell proliferation and are known to drive oncogenesis when overactivated. Herein we report a gatekeeper function of the two pathways by working in synergy to suppress liver tumorigenesis. Hepatocyte-specific deletion of both Shp2/Ptpn11 and Ikkβ in mice, which promote Ras/Erk and NF-κB signaling, respectively, exacerbated chemical carcinogenesis and even triggered spontaneous development of hepatocellular carcinoma (HCC). We show that the unanticipated severe tumor phenotype was contributed collectively by severe cholestasis, metabolic changes, upregulated cell-cycle progression, and disruption of circadian rhythm in mutant hepatocytes. Remarkably, human HCCs with dysregulated circadian gene expression displayed downregulation of Ras/Erk and NF-κB signaling and poor prognosis. Together, these data indicate that at the …

The postnatal development and maturation of the liver, the major metabolic organ, are inadequately understood. We have analyzed 52,834 single-cell transcriptomes and identified 31 cell types or states in mouse livers at postnatal days 1, 3, 7, 21, and 56. We observe unexpectedly high levels of hepatocyte heterogeneity in the developing liver and the progressive construction of the zonated metabolic functions from pericentral to periportal hepatocytes, which is orchestrated with the development of sinusoid endothelial, stellate, and Kupffer cells. Trajectory and gene regulatory analyses capture 36 transcription factors, including a circadian regulator, Bhlhe40, in programming liver development. Remarkably, we identified a special group of macrophages enriched at day 7 with a hybrid phenotype of macrophages and endothelial cells, which may regulate sinusoidal construction and Treg-cell function. This study …

Approximately 75% of failed pregnancies are considered to be due to embryo implantation failure or defects. Nevertheless, the explicit signaling mechanisms governing this process have not yet been elucidated. Here, we found that conditional deletion of the Shp2 gene in mouse uterine stromal cells deferred embryo implantation and inhibited the decidualization of stromal cells, which led to embryonic developmental delay and to the death of numerous embryos mid-gestation, ultimately reducing female fertility. The absence of Shp2 in stromal cells increased the proliferation of endometrial epithelial cells, thereby disturbing endometrial epithelial remodeling. However, Shp2 deletion impaired the proliferation and polyploidization of stromal cells, which are distinct characteristics of decidualization. In human endometrial stromal cells (hESCs), Shp2 expression gradually increased during the decidualization process. Knockout of Shp2 blocked the decidual differentiation of hESCs, while Shp2 overexpression had the opposite effect. Shp2 knockout inhibited the proliferation of hESCs during decidualization. Whole gene expression profiling analysis of hESCs during the decidualization process showed that Shp2 deficiency disrupted many signaling transduction pathways and gene expression. Analyses of hESCs and mouse uterine tissues confirmed that the signaling pathways extracellular regulated protein kinases (ERK), protein kinase B (AKT), signal transducer and activator of transcription 3 (STAT3) and their downstream transcription factors CCAAT/enhancer binding protein β (C/EBPβ) and Forkhead box transcription factor O1 (FOXO-1) were …

Bony fusion caused by pathological new bone formation manifests the clinical feature of ankylosing spondylitis (AS). However, the underlying mechanism remains elusive. Here we discovered spontaneous kyphosis, arthritis and bony fusion in mature CD4-Cre;Ptpn11f/f mice, which present the pathophysiological features of AS. A population of CD4-Cre-expressing proliferating chondrocytes was SHP2 deficient, which could differentiate into pre-hypertrophic and hypertrophic chondrocytes. Functionally, SHP2 deficiency in chondrocytes impeded the fusion of epiphyseal plate and promoted chondrogenesis in joint cavity and enthesis. Mechanistically, aberrant chondrocytes promoted ectopic new bone formation through BMP6/pSmad1/5 signaling. It is worth emphasizing that such pathological thickness of growth plates was evident in adolescent humans with enthesitis-related arthritis, which could progress to AS in …

The mechanisms of Myc-driven liver tumorigenesis are inadequately understood. Herein we show that Myc-driven hepatocellular carcinoma (HCC) is dramatically aggravated in mice with hepatocyte-specific Ptpn11/Shp2 deletion. However, Myc-induced tumors develop selectively from the rare Shp2-positive hepatocytes in Shp2-deficent liver, and Myc-driven oncogenesis depends on an intact Ras-Erk signaling promoted by Shp2 to sustain Myc stability. Despite a stringent requirement of Shp2 cell autonomously, Shp2 deletion induces an immunosuppressive environment, resulting in defective clearance of tumor-initiating cells and aggressive tumor progression. The basal Wnt/β-catenin signaling is upregulated in Shp2-deficient liver, which is further augmented by Myc transfection. Ablating Ctnnb1 suppresses Myc-induced HCC in Shp2-deficient livers, revealing an essential role of β-catenin. Consistently, Myc …

The mechanisms underlying the recurrence and metastasis of hepatocellular carcinoma (HCC) are poorly understood. In 2015, Zhuang and her colleagues identified a unique histopathological structure in HCC tissues, which they dubbed VETC, standing for vessels that encapsulate tumor clusters. 1 In the VETC structure, sinusoid-like vessels form a cobweb-like network that encapsulates individual tumor cell clusters. These endothelium-wrapped tumor cell clusters were released into the blood stream and formed metastatic tumors in a manner independent of epithelialmesenchymal transition (EMT), another well-known tumor metastatic process. 2 Mechanistically, the authors found that angiopoietin-2 (Angpt2) secreted by tumor cells played a critical role in the induction of VETC formation and intrahepatic tumor metastasis and recurrence.In this issue, Zhuang’s group report a very interesting functional relationship …

Obesity is caused by a long-term imbalance between energy intake and consumption and is regulated by multiple signals. This study investigated the effect of signaling scaffolding protein Gab2 on obesity and its relevant regulation mechanism. Gab2 knockout (KO) and wild-type (WT) mice were fed with a standard diet (SD) or high-fat diet (HFD) for 12 weeks. The results showed that the a high-fat diet-induced Gab2 expression in adipose tissues, but deletion of Gab2 attenuated weight gain and improved glucose tolerance in mice fed with a high-fat diet. White adipose tissue and systemic inflammations were reduced in HFD-fed Gab2 deficiency mice. Gab2 deficiency increased the expression of Ucp1 and other thermogenic genes in brown adipose tissue. Furthermore, the regulation of Gab2 on the mature differentiation and function of adipocytes was investigated in vitro using primary or immortalized brown …

Compared with our closest living evolutionary cousins, humans appear unusually prone to develop carcinomas (cancers arising from epithelia). The SIGLEC12 gene, which encodes the Siglec‐XII protein expressed on epithelial cells, has several uniquely human features: a fixed homozygous missense mutation inactivating its natural ligand recognition property; a polymorphic frameshift mutation eliminating full‐length protein expression in~ 60%–70% of worldwide human populations; and, genomic features suggesting a negative selective sweep favoring the pseudogene state. Despite the loss of canonical sialic acid binding, Siglec‐XII still recruits Shp2 and accelerates tumor growth in a mouse model. We hypothesized that dysfunctional Siglec‐XII facilitates human carcinoma progression, correlating with known tumorigenic signatures of Shp2‐dependent cancers. Immunohistochemistry was used to detect Siglec …