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Abstract Background Drug resistance is an important factor affecting the efficacy of chemotherapy in patients with colon cancer. However, clinical markers for diagnosing drug resistance of tumor cells are not only a few in number, but also low in specificity, and the mechanism of action of tumor cell drug resistance remains unclear. Methods Dipeptidase 1 (DPEP1) expression was analyzed using the cancer genome atlas (TCGA) and genotype‐Tissue Expression pan‐cancer data. Survival analysis was performed using the survival package in R software to assess the prognostic value of DPEP1 expression in colon cancer. Correlation and Venn analyses were adopted to identify key genes. Immunohistochemistry, western blot, qRT–PCR, Co‐immunoprecipitation, and dual‐luciferase reporter experiments were carried out to explore the underlying associations between DPEP1 and Achaete scute‐like 2 (ASCL2). MTT assays were used to evaluate the role of DPEP1 and ASCL2 in colon cancer drug resistance. Results DPEP1 was highly expressed in colon cancer tissues. DPEP1 expression correlated negatively with disease‐specific survival but not with overall survival. Bioinformatics analysis and experiments showed that the expressions of DPEP1 and ASCL2 in colon cancer tissues were markedly positively correlated. Mechanistic research indicated that DPEP1 enhanced the stability of protein ASCL2 by inhibiting its ubiquitination‐mediated degradation. In turn, ASCL2 functioned as a transcription factor to activate the transcriptional activity of the DPEP1 gene and boost its expression. Furthermore, DPEP1 also could enhance the expression of colon cancer stem cell markers (LGR5, CD133, and CD44), which strengthened the tolerance of colon cancer cells to chemotherapy drugs. Conclusions Our findings reveal that the DPEP1 enhances the stemness of tumor cells by forming a positive feedback loop with ASCL2 to improve resistance to chemotherapy drugs.

Abstract Background To investigate the role of achaete-scute complex-like 2 (ASCL2) in stomach adenocarcinoma (STAD), we analyze whether ASCL2 suppression could retard cancer development and further observe the relevance between ASCL2 and inflammation via Toll-like receptor 4 (TLR4) activation in STAD, both in vitro and in vivo. Methods Proliferation, development, inflammation, and apoptosis in STAD are observed using sh-ASCL2 lentivirus via TLR4 activation in vitro and in vivo. The relationship between ASCL2 and inflammation is analyzed. Western blotting of ASCL2 with the target protein of immune-associated cells is performed. The prognosis of STAD and associated ASCL2 mutation are analyzed. Results The ASCL2 level in STAD tumor tissues is increased, compared to normal tissues, and brings a worse prognosis. The ASCL2 shows a negative correlation with inflammation, and TLR4 reveals a positive correlation with gastric cancer. ASCL2 expression is high in MGC803 cells. Sh-ASCL2 could reduce STAD development by decreasing proliferation, tumor volume, and biomarker levels and increasing apoptosis in vitro and in vivo. The inflammatory role of ASCL2 is regulated through TLR4 activation. ASCL2 levels may be related to CNTNAP3, CLIP1, C9orf84, ARIH2, and IL1R2 mutations; positively correlated with M2 macrophage and T follicular helper cell levels; negatively correlated with neutrophil, dendritic cell, monocyte, CD8 T cell, and M1 macrophage levels; and involved in STAD prognosis. Conclusions The ASCL2 may adjust inflammation in STAD through TLR4 activation and may be associated with related immune cells. ASCL2 is possibly an upstream target factor of the TLR4 signaling pathway.

Background: Drug resistance is an important factor affecting the efficacy of chemotherapy in patients with colon cancer. However, clinical markers for diagnosing drug resistance of tumor cells are not only a few in number, but also low in specificity, and the mechanism of action of tumor cell drug resistance remains unclear. Methods: Dipeptidase 1 (DPEP1) expression was analyzed using the cancer genome atlas (TCGA) and genotype‐Tissue Expression pan‐cancer data. Survival analysis was performed using the survival package in R software to assess the prognostic value of DPEP1 expression in colon cancer. Correlation and Venn analyses were adopted to identify key genes. Immunohistochemistry, western blot, qRT–PCR, Co‐immunoprecipitation, and dual‐luciferase reporter experiments were carried out to explore the underlying associations between DPEP1 and Achaete scute‐like 2 (ASCL2). MTT assays were used to evaluate the role of DPEP1 and ASCL2 in colon cancer drug resistance. Results: DPEP1 was highly expressed in colon cancer tissues. DPEP1 expression correlated negatively with disease‐specific survival but not with overall survival. Bioinformatics analysis and experiments showed that the expressions of DPEP1 and ASCL2 in colon cancer tissues were markedly positively correlated. Mechanistic research indicated that DPEP1 enhanced the stability of protein ASCL2 by inhibiting its ubiquitination‐mediated degradation. In turn, ASCL2 functioned as a transcription factor to activate the transcriptional activity of the DPEP1 gene and boost its expression. Furthermore, DPEP1 also could enhance the expression of colon cancer stem cell markers (LGR5, CD133, and CD44), which strengthened the tolerance of colon cancer cells to chemotherapy drugs. Conclusions: Our findings reveal that the DPEP1 enhances the stemness of tumor cells by forming a positive feedback loop with ASCL2 to improve resistance to chemotherapy drugs. [ABSTRACT FROM AUTHOR]

• tRF-18-8R6546D2 is a tRNA-derived RNA fragment that promotes PAAD progression. • tRF-18-8R6546D2 can be used for diagnosis and prognosis prediction of PAAD. • tRF-18-8R6546D2 inhibits the expression of ASCL2 and further regulates its downstream genes such as MYC and CASP3. • Suggested a new mechanism of tRF-18-8R6546D2 engaged pathway in PAAD progression. Pancreatic adenocarcinoma (PAAD) is a life-threatening cancer. Exploring new diagnosis and treatment targets helps improve its prognosis. tRNA-derived small non-coding RNAs (tsRNAs) are a novel type of gene expression regulators and their dysregulation is closely related to many human cancers. Yet the expression and functions of tsRNAs in PAAD are not well understood. Our study used RNA sequencing to identify tsRNA expression profiles in PAAD cells cultured in no or high glucose media and found tRF-18-8R6546D2 was an uncharacterized tsRNA, which has significantly high expression in PAAD cells and tissues. Clinically, tRF-18-8R6546D2 is linked to poor prognosis in PAAD patients and can be used to distinguish them from healthy populations. Functionally, in vitro and vivo, tRF-18-8R6546D2 over-expression promoted PAAD cell proliferation, migration and invasion, inhibited apoptosis, whereas tRF-18-8R6546D2 knock-down showed opposite effects. Mechanistically, tRF-18-8R6546D2 promoted PAAD malignancy partly by directly silencing ASCL2 and further regulating its downstream genes such as MYC and CASP3. These findings show that tRF-18-8R6546D2 is a novel oncogenic factor and can be a promising diagnostic or prognostic biomarker and therapeutic target for PAAD. [ABSTRACT FROM AUTHOR]

Autophagy is a highly conserved process that is vital for tumor progression and treatment response. Although autophagy is proposed to maintain the stemness phenotype in adult diffuse glioma, the molecular basis of the link between autophagy and stemness is poorly understood, which makes it impossible to effectively screen for the population that will benefit from autophagy‐targeted treatment. Here, ATG9B as essential for self‐renewal capacity and tumor‐propagation potential is identified. Notably, ASCL2 transcriptionally regulates the expression of ATG9B to maintain stemness properties. The ASCL2‐ATG9B axis is an independent prognostic biomarker and indicator of autophagic activity. Furthermore, the highly effective blood–brain barrier (BBB)‐permeable autophagy inhibitor ROC‐325, which can significantly inhibit the progression of ASCL2‐ATG9B axisHigh gliomas as a single agent is investigated. These data demonstrate that a new ASCL2‐ATG9B signaling axis is crucial for maintaining the stemness phenotype and tumor progression, revealing a potential autophagy inhibition strategy for adult diffuse gliomas. [ABSTRACT FROM AUTHOR]

Background: To investigate the role of achaete-scute complex-like 2 (ASCL2) in stomach adenocarcinoma (STAD), we analyze whether ASCL2 suppression could retard cancer development and further observe the relevance between ASCL2 and inflammation via Toll-like receptor 4 (TLR4) activation in STAD, both in vitro and in vivo. Methods: Proliferation, development, inflammation, and apoptosis in STAD are observed using sh-ASCL2 lentivirus via TLR4 activation in vitro and in vivo. The relationship between ASCL2 and inflammation is analyzed. Western blotting of ASCL2 with the target protein of immune-associated cells is performed. The prognosis of STAD and associated ASCL2 mutation are analyzed. Results: The ASCL2 level in STAD tumor tissues is increased, compared to normal tissues, and brings a worse prognosis. The ASCL2 shows a negative correlation with inflammation, and TLR4 reveals a positive correlation with gastric cancer. ASCL2 expression is high in MGC803 cells. Sh-ASCL2 could reduce STAD development by decreasing proliferation, tumor volume, and biomarker levels and increasing apoptosis in vitro and in vivo. The inflammatory role of ASCL2 is regulated through TLR4 activation. ASCL2 levels may be related to CNTNAP3, CLIP1, C9orf84, ARIH2, and IL1R2 mutations; positively correlated with M2 macrophage and T follicular helper cell levels; negatively correlated with neutrophil, dendritic cell, monocyte, CD8 T cell, and M1 macrophage levels; and involved in STAD prognosis. Conclusions: The ASCL2 may adjust inflammation in STAD through TLR4 activation and may be associated with related immune cells. ASCL2 is possibly an upstream target factor of the TLR4 signaling pathway. [ABSTRACT FROM AUTHOR]

The achaete-scute complex-like (ASCL) family, also referred to as 'achaete-scute complex homolog' or 'achaete-scute family basic helix-loop-helix transcription factor', is critical for proper development of the nervous system and deregulation of ASCL plays a key role in psychiatric and neurological disorders. The ASCL family consists of five members, namely ASCL1, ASCL2, ASCL3, ASCL4 and ASCL5. The ASCL1 gene serves as a potential oncogene during lung cancer development. There is a correlation between increased ASCL2 expression and colon cancer development. Inhibition of ASCL2 reduced cellular proliferation and tumor growth in xenograft tumor experiments. Although previous studies demonstrated involvement of ASCL1 and ASCL2 in tumor development, little is known on the remaining ASCL family members and their potential effect on tumorigenesis. Therefore, a holistic approach to investigating the expression of ASCL family genes in diverse types of cancer may provide new insights in cancer research. In this study, we utilized a web-based microarray database (Oncomine; www.oncomine.org) to analyze the transcriptional expression of the ASCL family in clinical cancer and normal tissues. Our bioinformatics analysis revealed the potential involvement of multiple ASCL family members during tumor onset and progression in multiple types of cancer. Compared to normal tissue, ASCL1 exhibited a higher expression in cancers of the lung, pancreas, kidney, esophagus and head and neck, whereas ASCL2 exhibited a high expression in cancers of the breast, colon, stomach, lung, head and neck, ovary and testis. ASCL3, however, exhibited a high expression only in breast cancer. Interestingly, ASCL1 expression was downregulated in melanoma and in cancers of the bladder, breast, stomach and colon. ASCL2 exhibited low expression levels in sarcoma, melanoma, brain and prostate cancers. Reduction in the expression of ASCL3 was detected in lymphoma, bladder, cervical, kidney and epithelial cancers. Similarly, ASCL5 exhibited low expression in the majority of brain cancer subtypes, such as glioblastoma and oligodendroglioma. This analysis supports the hypothesis that specific ASCL members may play an important role in cancer development. Collectively, our data suggest that alterations in the expression of ASCL gene family members are correlated with cancer development. Furthermore, ASCL family members were categorized according to cancer subtype. The aim of this report was to provide novel insights to the significance of the ASCL family in various cancers and our findings suggested that the ASCL gene family may be an ideal target for future cancer studies.

Abstract Background Wnt signaling is a critical determinant for the maintenance and differentiation of stem/progenitor cells, including trophoblast stem cells during placental development. Hyperactivation of Wnt signaling has been shown to be associated with human trophoblast diseases. However, little is known about the impact and underlying mechanisms of excessive Wnt signaling during placental trophoblast development. Results In the present work, we observed that two inhibitors of Wnt signaling, secreted frizzled-related proteins 1 and 5 (Sfrp1 and Sfrp5), are highly expressed in the extraembryonic trophoblast suggesting possible roles in early placental development. Sfrp1 and Sfrp5 double knockout mice exhibited disturbed trophoblast differentiation in the placental ectoplacental cone (EPC), which contains the precursors of trophoblast giant cells (TGCs) and spongiotrophoblast cells. In addition, we employed mouse models expressing a truncated β-catenin with exon 3 deletion globally and trophoblast-specifically, as well as trophoblast stem cell lines, and unraveled that hyperactivation of canonical Wnt pathway exhausted the trophoblast precursor cells in the EPC, resulting in the overabundance of giant cells at the expense of spongiotrophoblast cells. Further examination uncovered that hyperactivation of canonical Wnt pathway disturbed trophoblast differentiation in the EPC via repressing Ascl2 expression. Conclusions Our investigations provide new insights that the homeostasis of canonical Wnt-β-catenin signaling is essential for EPC trophoblast differentiation during placental development, which is of high clinical relevance, since aberrant Wnt signaling is often associated with trophoblast-related diseases.

Hybrid phenotypes that contribute to postzygotic reproductive isolation often exhibit pronounced asymmetry, both between reciprocal crosses and between the sexes in accordance with Haldane's rule. Inviability in mammalian hybrids is associated with parent‐of‐origin placental growth abnormalities for which misregulation of imprinted gene (IGs) is the leading candidate mechanism. However, direct evidence for the involvement of IGs in hybrid growth dysplasia is limited. We used transcriptome and reduced representation bisulfite sequencing to conduct the first genome‐scale assessment of the contribution of IGs to parent‐of‐origin placental growth dysplasia in the cross between the house mouse (Mus musculus domesticus) and the Algerian mouse (Mus spretus). IGs with transgressive expression and methylation were concentrated in the Kcnq1 cluster, which contains causal genes for prenatal growth abnormalities in mice and humans. Hypermethylation of the cluster's imprinting control region, and consequent misexpression of the genes Phlda2 and Ascl2, is a strong candidate mechanism for transgressive placental undergrowth. Transgressive placental and gene regulatory phenotypes, including expression and methylation in the Kcnq1 cluster, were more extreme in hybrid males. Although consistent with Haldane's rule, male‐biased defects are unexpected in rodent placenta because the X‐chromosome is effectively hemizygous in both sexes. In search of an explanation, we found evidence of leaky imprinted (paternal) X‐chromosome inactivation in hybrid female placenta, an epigenetic disturbance that may buffer females from the effects of X‐linked incompatibilities to which males are fully exposed. Sex differences in chromatin structure on the X and sex‐biased maternal effects are nonmutually exclusive alternative explanations for adherence to Haldane's rule in hybrid placenta. The results of this study contribute to understanding the genetic basis of hybrid inviability in mammals, and the role of IGs in speciation. [ABSTRACT FROM AUTHOR]

Summary: Organoid technology provides the possibility of culturing patient-derived colon tissue and colorectal cancers (CRCs) while maintaining all functional and phenotypic characteristics. Labeling stem cells, especially in normal and benign tumor organoids of human colon, is challenging and therefore limits maximal exploitation of organoid libraries for human stem cell research. Here, we developed STAR (stem cell Ascl2 reporter), a minimal enhancer/promoter element that reports transcriptional activity of ASCL2, a master regulator of LGR5+ intestinal stem cells. Using lentiviral infection, STAR drives specific expression in stem cells of normal organoids and in multiple engineered and patient-derived CRC organoids of different genetic makeup. STAR reveals that differentiation hierarchies and the potential for cell fate plasticity are present at all stages of human CRC development. Organoid technology, in combination with the user-friendly nature of STAR, will facilitate basic research into human adult stem cell biology.

Background: Wnt signaling is a critical determinant for the maintenance and differentiation of stem/progenitor cells, including trophoblast stem cells during placental development. Hyperactivation of Wnt signaling has been shown to be associated with human trophoblast diseases. However, little is known about the impact and underlying mechanisms of excessive Wnt signaling during placental trophoblast development. Results: In the present work, we observed that two inhibitors of Wnt signaling, secreted frizzled-related proteins 1 and 5 (Sfrp1 and Sfrp5), are highly expressed in the extraembryonic trophoblast suggesting possible roles in early placental development. Sfrp1 and Sfrp5 double knockout mice exhibited disturbed trophoblast differentiation in the placental ectoplacental cone (EPC), which contains the precursors of trophoblast giant cells (TGCs) and spongiotrophoblast cells. In addition, we employed mouse models expressing a truncated β-catenin with exon 3 deletion globally and trophoblast-specifically, as well as trophoblast stem cell lines, and unraveled that hyperactivation of canonical Wnt pathway exhausted the trophoblast precursor cells in the EPC, resulting in the overabundance of giant cells at the expense of spongiotrophoblast cells. Further examination uncovered that hyperactivation of canonical Wnt pathway disturbed trophoblast differentiation in the EPC via repressing Ascl2 expression. Conclusions: Our investigations provide new insights that the homeostasis of canonical Wnt-β-catenin signaling is essential for EPC trophoblast differentiation during placental development, which is of high clinical relevance, since aberrant Wnt signaling is often associated with trophoblast-related diseases. [ABSTRACT FROM AUTHOR]

To decrease bowel cancer incidence and improve survival, we need to understand the mechanisms that drive tumorigenesis. Recently, B-cell lymphoma 3 (BCL-3; a key regulator of NF-κB signalling) has been recognised as an important oncogenic player in solid tumours. Although reported to be overexpressed in a subset of colorectal cancers (CRCs), the role of BCL-3 expression in colorectal tumorigenesis remains poorly understood. Despite evidence in the literature that BCL-3 may interact with β-catenin, it is perhaps surprising, given the importance of deregulated Wnt/β-catenin/T-cell factor (TCF) signalling in colorectal carcinogenesis, that the functional significance of this interaction is not known. Here, we show for the first time that BCL-3 acts as a co-activator of β-catenin/TCF-mediated transcriptional activity in CRC cell lines and that this interaction is important for Wnt-regulated intestinal stem cell gene expression. We demonstrate that targeting BCL-3 expression (using RNA interference) reduced β-catenin/TCF-dependent transcription and the expression of intestinal stem cell genes LGR5 and ASCL2. In contrast, the expression of canonical Wnt targets Myc and cyclin D1 remained unchanged. Furthermore, we show that BCL-3 increases the functional stem cell phenotype, as shown by colorectal spheroid and tumoursphere formation in 3D culture conditions. We propose that BCL-3 acts as a driver of the stem cell phenotype in CRC cells, potentially promoting tumour cell plasticity and therapeutic resistance. As recent reports highlight the limitations of directly targeting cancer stem cells (CSCs), we believe that identifying and targeting drivers of stem cell plasticity have significant potential as new therapeutic targets. This article has an associated First Person interview with the first author of the paper.

The esophagus is protected from the hostile environment by a stratified epithelium, which renews rapidly. Homeostasis of this epithelium is ensured by a rare population of stem cells in the basal layer: Keratin 15+ (Krt15+) cells. However, little is known about the molecular mechanisms regulating their distinct features, namely self-renewal, potency and epithelial regeneration. Achaete-scute family BHLH transcription factor 2 (ASCL2) is strongly upregulated in Krt15+ stem cells and is known to contribute to stem cell maintenance in other tissues. Herein, we investigated the role of ASCL2 in maintaining homeostasis under normal and stress conditions in the esophageal epithelium. ASCL2 overexpression severely dysregulated cell differentiation and cell fate. Proliferation was also reduced due potentially to a blockage in the G1 phase of the cell cycle or an induction of quiescence. Mass spectrometry analysis confirmed alterations in several proteins associated with differentiation and the cell cycle. In addition, overexpression of ASCL2 enhanced resistance to radiation and chemotherapeutic drugs. Overall, these results denote the role of ASCL2 as a key regulator of the proliferation-differentiation equilibrium in the esophageal epithelium., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

The molecular mediators underlying the effects of inflammation on neural stem cells (NSCs) are not fully characterized. In this study, we identified Ascl2 as a downstream basic helix-loop-helix (bHLH) transcription factor in NSCs following exposure to TNFα. Under normal conditions, Ascl2 expression is inhibited at post-transcriptional levels by miR-26a, which targets the 3' untranslated region (UTR) of Ascl2. Upon exposure to TNFα, miR-26a expression is reduced, which leads to up-regulation of Ascl2. Overexpression of Ascl2 promotes neuronal differentiation, reduces proliferation, and increases the level of cleaved CASPASE 3 in NSCs, as observed in the in vitro and in ovo experiments. Ascl2 may serve in NSCs as a standby factor that readily responds to TNFα, which is often induced in inflammatory situations. In a chronic inflammatory condition with consistent up-regulation of TNFα, overexpression of Ascl2 may inhibit neurogenesis as a net result. [ABSTRACT FROM AUTHOR]

Abstract Inflammatory bowel disease (IBD) has been well-documented as a chronic gastrointestinal autoimmune disease, but its etiology remains to be elusive. Ascl2 (achaete-scute complex homologue 2), identified as a homologue of the Drosophila achaete-scute gene, has been shown to play an essential for the pathogenesis of autoimmune diseases and cancers. However, whether it is associated with the pathogenesis of IBD remains unclear. Here, we demonstrated that Ascl2 was greatly down-regulated in human IBD and experimental colitis. Interestingly, CD4+ T cell expression of Ascl2 was regulated by intestinal microbiota. Moreover, we revealed that Ascl2 inhibited the differentiation of Th17 cells and restrained their pathogenicity through facilitating IL-10 production. We further showed that Blimp-1 might be involved in the Ascl2-inducing IL-10 expression in CD4+ T cells under Th17 differentiating condition. Notably, lentivirus-mediated overexpression of Ascl2 remarkably alleviated the severity of 2,4,6-trinitrobenzenesulfonic acid solution (TNBS)-induced colitis in mice, with decreased level of colonic IL-17A. Our findings demonstrated an unappreciated mechanism whereby Ascl2 negatively modulates pathogenic Th17 cell differentiation via promoting IL-10 production, and alleviates intestinal inflammation. Thus, Ascl2 may serve as a novel therapeutic target of IBD. Highlights • Ascl2 expression is significantly down-regulated in patients with IBD. • Ascl2 expression is regulated by intestinal microbiota. • Ascl2 suppresses Th17 differentiation and facilitates IL-10 production. • In vivo over expression of Ascl2 alleviates experimental colitis in mice. [ABSTRACT FROM AUTHOR]

Summary: In eutherian mammals, the placenta plays a critical role in embryo development by supplying nutrients and hormones and mediating interaction with the mother. To establish the fine connection between mother and embryo, the placenta needs to be formed normally, but the mechanism of placental differentiation is not fully understood. We previously revealed that mouse prolyl oligopeptidase (POP) plays a role in trophoblast stem cell (TSC) differentiation into two placental cell types, spongiotrophoblasts (SpT) and trophoblast giant cells. Here, we focused on SpT differentiation and attempted to elucidate a molecular mechanism. For Ascl2 , Arnt , and Egfr genes that are indispensable for SpT formation, we found that a POP-specific inhibitor, SUAM-14746, significantly decreased Ascl2 expression, which was consistent with a significant decrease in expression of Flt1 , a gene downstream of Ascl2. Although this downregulation was unlikely to be mediated by the PI3K-Akt pathway, our results indicated that POP controls TSC differentiation into SpT by regulating the Ascl2 gene. [ABSTRACT FROM AUTHOR]

Trans -differentiation from an adenocarcinoma to a small cell neuroendocrine state is associated with therapy resistance in multiple cancer types. To gain insight into the underlying molecular events of the trans -differentiation, we perform a multi-omics time course analysis of a pan-small cell neuroendocrine cancer model (termed PARCB), a forward genetic transformation using human prostate basal cells and identify a shared developmental, arc-like, and entropy-high trajectory among all transformation model replicates. Further mapping with single cell resolution reveals two distinct lineages defined by mutually exclusive expression of ASCL1 or ASCL2. Temporal regulation by groups of transcription factors across developmental stages reveals that cellular reprogramming precedes the induction of neuronal programs. TFAP4 and ASCL1/2 feedback are identified as potential regulators of ASCL1 and ASCL2 expression. Our study provides temporal transcriptional patterns and uncovers pan-tissue parallels between prostate and lung cancers, as well as connections to normal neuroendocrine cell states. [Display omitted] • PARCB temporal model profiling informs key aspects of SCNPC trans -differentiation • Trans -differentiation trajectory resembles a common developmental arc-like pattern • ASCL1 and ASCL2 mark distinct bifurcating SCNPC trans -differentiation trajectories • TFAP4 as a common regulator of ASCL1/2 implicated in SCNPC trans -differentiation Chen et al. use temporal profiling of a small cell neuroendocrine prostate cancer model to inform anti-androgen therapy-induced trans -differentiation. An arc-like trajectory common to developmental biology is observed, and a bifurcation marked by ASCL1 and ASCL2, with parallels to SCLC. TFAP4 is identified as a common regulator of ASCL1 and ASCL2. [ABSTRACT FROM AUTHOR]

Aberrant Wnt/β-catenin signaling is a common event during human colorectal cancer (CRC) development. Previously, we characterized members of the L1 family of cell adhesion receptors as targets of β-catenin-LEF1/TCF transactivation that are expressed at the invasive CRC tissue edge. Overexpression of L1 in CRC cells confers enhanced motility, tumorigenesis and liver metastasis. We identified several downstream targets of L1-mediated signaling that are considered key intestinal stem cell signature genes. Here, we investigated the involvement of ASCL2, a Wnt target gene and key determinant of intestinal stem cell state, in L1-mediated CRC progression. In L1 overexpressing CRC cells we found an increase in ASCL2, a decrease in E-cadherin and accumulation of nuclear β-catenin, β-catenin-LEF1/TCF transactivation and target gene expression. The increase in ASCL2 by L1 overexpression enhanced ASCL2 target gene expression, conferred increased motility, tumorigenesis and metastasis, similar to L1 overexpression. Suppression of ASCL2 in cells expressing L1 blocked these tumorigenic properties. In human CRC tissue, ASCL2 was detected in the nuclei of cells at invasive areas of the tumor that also expressed L1. The results suggest that increased ASCL2 expression is a critical step in L1-mediated CRC progression. [ABSTRACT FROM AUTHOR]

Myogenic regulatory factors (MRFs), including Myf5, MyoD (Myod1) and Myog, are muscle-specific transcription factors that orchestrate myogenesis. Although MRFs are essential for myogenic commitment and differentiation, timely repression of their activity is necessary for the self-renewal and maintenance of muscle stem cells (satellite cells). Here, we define Ascl2 as a novel inhibitor of MRFs. During mouse development, Ascl2 is transiently detected in a subpopulation of Pax7+ MyoD+ progenitors (myoblasts) that become Pax7+ MyoD− satellite cells prior to birth, but is not detectable in postnatal satellite cells. Ascl2 knockout in embryonic myoblasts decreases both the number of Pax7+ cells and the proportion of Pax7+ MyoD− cells. Conversely, overexpression of Ascl2 inhibits the proliferation and differentiation of cultured myoblasts and impairs the regeneration of injured muscles. Ascl2 competes with MRFs for binding to E-boxes in the promoters of muscle genes, without activating gene transcription. Ascl2 also forms heterodimers with classical E-proteins to sequester their transcriptional activity on MRF genes. Accordingly, MyoD or Myog expression rescues myogenic differentiation despite Ascl2 overexpression. Ascl2 expression is regulated by Notch signaling, a key governor of satellite cell self-renewal. These data demonstrate that Ascl2 inhibits myogenic differentiation by targeting MRFs and facilitates the generation of postnatal satellite cells. [ABSTRACT FROM AUTHOR]

The achaete-scute complex-like (ASCL) family, also referred to as 'achaete-scute complex homolog' or 'achaete-scute family basic helix-loop-helix transcription factor', is critical for proper development of the nervous system and deregulation of ASCL plays a key role in psychiatric and neurological disorders. The ASCL family consists of five members, namely ASCL1, ASCL2, ASCL3, ASCL4 and ASCL5. The ASCL1 gene serves as a potential oncogene during lung cancer development. There is a correlation between increased ASCL2 expression and colon cancer development. Inhibition of ASCL2 reduced cellular proliferation and tumor growth in xenograft tumor experiments. Although previous studies demonstrated involvement of ASCL1 and ASCL2 in tumor development, little is known on the remaining ASCL family members and their potential effect on tumorigenesis. Therefore, a holistic approach to investigating the expression of ASCL family genes in diverse types of cancer may provide new insights in cancer research. In this study, we utilized a web-based microarray database (Oncomine; www.oncomine.org) to analyze the transcriptional expression of the ASCL family in clinical cancer and normal tissues. Our bioinformatics analysis revealed the potential involvement of multiple ASCL family members during tumor onset and progression in multiple types of cancer. Compared to normal tissue, ASCL1 exhibited a higher expression in cancers of the lung, pancreas, kidney, esophagus and head and neck, whereas ASCL2 exhibited a high expression in cancers of the breast, colon, stomach, lung, head and neck, ovary and testis. ASCL3, however, exhibited a high expression only in breast cancer. Interestingly, ASCL1 expression was downregulated in melanoma and in cancers of the bladder, breast, stomach and colon. ASCL2 exhibited low expression levels in sarcoma, melanoma, brain and prostate cancers. Reduction in the expression of ASCL3 was detected in lymphoma, bladder, cervical, kidney and epithelial cancers. Similarly, ASCL5 exhibited low expression in the majority of brain cancer subtypes, such as glioblastoma and oligodendroglioma. This analysis supports the hypothesis that specific ASCL members may play an important role in cancer development. Collectively, our data suggest that alterations in the expression of ASCL gene family members are correlated with cancer development. Furthermore, ASCL family members were categorized according to cancer subtype. The aim of this report was to provide novel insights to the significance of the ASCL family in various cancers and our findings suggested that the ASCL gene family may be an ideal target for future cancer studies. [ABSTRACT FROM AUTHOR]

p57Kip2 is a cyclin/CDK inhibitor and a negative regulator of cell proliferation. Here, we report that p57 regulates intestinal stem cell (ISC) fate and proliferation in a CDK-independent manner during intestinal development. In the absence of p57, intestinal crypts exhibit an increased proliferation and an amplification of transit-amplifying cells and of Hopx+ ISCs, which are no longer quiescent, while Lgr5+ ISCs are unaffected. RNA sequencing (RNA-seq) analyses of Hopx+ ISCs show major gene expression changes in the absence of p57. We found that p57 binds to and inhibits the activity of Ascl2, a transcription factor critical for ISC specification and maintenance, by participating in the recruitment of a corepressor complex to Ascl2 target gene promoters. Thus, our data suggest that, during intestinal development, p57 plays a key role in maintaining Hopx+ ISC quiescence and repressing the ISC phenotype outside of the crypt bottom by inhibiting the transcription factor Ascl2 in a CDK-independent manner. [Display omitted] • p57kip2 regulates intestinal stem cell proliferation in a CDK-independent manner • p57Kip2 is expressed in Hopx+ cells during embryonic development • p57Kip2 represses the transcriptional activity of Ascl2 • p57Kip2 participates in the recruitment of a transcriptional corepressor complex During intestinal development, p57Kip2 regulates Hopx+ intestinal stem cell fate and proliferation in a CDK-independent manner. p57Kip2 can repress the transcriptional activity of Ascl2 by participating in the recruitment of a corepressor complex on Ascl2 target gene promoters. Loss of p57Kip2 leads to intestinal stem cell deregulation and dysplasia of the intestinal epithelium. [ABSTRACT FROM AUTHOR]

p57 Kip2 is a cyclin/CDK inhibitor and a negative regulator of cell proliferation. Here, we report that p57 regulates intestinal stem cell (ISC) fate and proliferation in a CDK-independent manner during intestinal development. In the absence of p57, intestinal crypts exhibit an increased proliferation and an amplification of transit-amplifying cells and of Hopx + ISCs, which are no longer quiescent, while Lgr5 + ISCs are unaffected. RNA sequencing (RNA-seq) analyses of Hopx + ISCs show major gene expression changes in the absence of p57. We found that p57 binds to and inhibits the activity of Ascl2, a transcription factor critical for ISC specification and maintenance, by participating in the recruitment of a corepressor complex to Ascl2 target gene promoters. Thus, our data suggest that, during intestinal development, p57 plays a key role in maintaining Hopx + ISC quiescence and repressing the ISC phenotype outside of the crypt bottom by inhibiting the transcription factor Ascl2 in a CDK-independent manner., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Imprinted genes are expressed primarily from one parental allele by virtue of a germ line epigenetic process. Achaete-scute complex homolog 2 ( Ascl2 aka Mash2 ) is a maternally expressed imprinted gene that plays a key role in placental and intestinal development. Loss-of-function of Ascl2 results in an expansion of the parietal trophoblast giant cell (P-TGC) lineage, an almost complete loss of Trophoblast specific protein alpha ( Tpbpa ) positive cells in the ectoplacental cone and embryonic failure by E10.5. Tpbpa expression marks the progenitors of some P-TGCs, two additional trophoblast giant cell lineages (spiral artery and canal), the spongiotrophoblast and the glycogen cell lineage. Using a transgenic model, here we show that elevated expression of Ascl2 reduced the number of P-TGC cells by 40%. Elevated Ascl2 also resulted in a marked loss of the spongiotrophoblast and a substantial mislocalisation of glycogen cells into the labyrinth. In addition, Ascl2-Tg placenta contained considerably more placental glycogen than wild type. Glycogen cells are normally located within the junctional zone in close contact with spongiotrophoblast cells, before migrating through the P-TGC layer into the maternal decidua late in gestation where their stores of glycogen are released. The failure of glycogen cells to release their stores of glycogen may explain both the inappropriate accumulation of glycogen and fetal growth restriction observed late in gestation in this model. In addition, using in a genetic cross we provide evidence that Ascl2 requires the activity of a second maternally expressed imprinted gene, Pleckstrin homology-like domain, family a, member 2 ( Phlda2 ) to limit the expansion of the spongiotrophoblast. This “belts and braces” approach demonstrates the importance of genomic imprinting in regulating the size of the placental endocrine compartment for optimal placental development and fetal growth. [ABSTRACT FROM AUTHOR]

Semaphorin- 3F ( SEMA3F), an axonal repulsant in nerve development, has been shown to inhibit the progression of human colorectal cancer ( CRC); however, the underlying mechanism remains elusive. In this study we found a negative correlation between the levels of SEMA3F and CXCR4 in CRC specimens from 85 patients, confirmed by bioinformatics analysis of gene expression in 229 CRC samples from the Cancer Genome Atlas. SEMA3Fhigh/ CXCR4low patients showed the lowest frequency of lymph node and distant metastasis and the longest survival. Mechanistically, SEMA3F inhibited the invasion and metastasis of CRC cells through PI3K-AKT-dependent down-regulation of the ASCL2-CXCR4 axis. Specifically, ASCL2 enhanced the invasion and metastasis of CRC cells in vitro and expression of ASCL2 correlated with distant metastasis, tumour size and poor overall survival in CRC patients. Treatment of CRC cells with the CXCR4 antagonist AMD3100 attenuated SEMA3F knockdown-induced invasion and metastasis of CRC cells in vitro and in vivo. Our study thus demonstrates that SEMA3F functions as a suppressor of CRC metastasis via down-regulating the ASCL2-CXCR4 axis. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Ascl2 has been shown to be involved in tumorigenesis in colorectal cancer (CRC), although its epigenetic regulatory mechanism is largely unknown. Here, we found that methylation of the Ascl2 promoter (bp -1670 ∼ -1139) was significantly increased compared to the other regions of the Ascl2 locus in CRC cells and was associated with elevated Ascl2 mRNA expression. Furthermore, we found that promoter methylation was predictive of CRC patient survival after analyzing DNA methylation data, RNA-Seq data, and clinical data of 410 CRC patient samples from the MethHC database, the MEXPRESS database, and the Cbioportal website. Using the established TET methylcytosine dioxygenase 2 (TET2) knockdown and ectopic TET2 catalytic domain-expression cell models, we performed glucosylated hydroxymethyl-sensitive quatitative PCR (qPCR), real-time PCR, and Western blot assays to further confirm that hypermethylation of the Ascl2 promoter, and elevated Ascl2 expression in CRC cells was partly due to the decreased expression of TET2. Furthermore, BCLAF1 was identified as a TET2 interactor in CRC cells by LC-MS/MS, coimmunoprecipitation, immunofluorescence colocalization, and proximity ligation assays. Subsequently, we found the TET2-BCLAF1 complex bound to multiple elements around CCGG sites at the Ascl2 promoter and further restrained its hypermethylation by inducing its hydroxymethylation using chromatin immunoprecipitation-qPCR and glucosylated hydroxymethyl-qPCR assays. Finally, we demonstrate that TET2-modulated Ascl2-targeted stem gene expression in CRC cells was independent of Wnt signaling. Taken together, our data suggest an additional option for inhibiting Ascl2 expression in CRC cells through TET2-BCLAF1-mediated promoter methylation, Ascl2-dependent self-renewal of CRC progenitor cells, and TET2-BCLAF1-related CRC progression., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Abstract: Several imprinted genes have been implicated in the regulation of placental function and embryonic growth. On distal mouse chromosome 7, two clusters of imprinted genes, each regulated by its own imprinting center (IC), are separated by a poorly characterized region of 280kb (the IC1–IC2 interval). We previously generated a mouse line in which this IC1–IC2 interval has been deleted (Del 7AI allele) and found that maternal inheritance of this allele results in low birth weights in newborns. Here we report that Del 7AI causes a partial loss of Ascl2, a maternally expressed gene in the IC2 cluster, which when knocked out leads to embryonic lethality at midgestation due to a lack of spongiotrophoblast formation. The hypomorphic Ascl2 allele causes embryonic growth restriction and an associated placental phenotype characterized by a reduction in placental weight, reduced spongiotrophoblast population, absence of glycogen cells, and an expanded trophoblast giant cell layer. We also uncovered severe defects in the labyrinth layer of maternal mutants including increased production of the trilaminar labyrinth trophoblast cell types and a disorganized labyrinthine vasculature. Our results have important implications for our understanding of the role played by the spongiotrophoblast layer during placentation and show that regulation of the dosage of the imprinted gene Ascl2 can affect all three layers of the chorio-allantoic placenta. [Copyright &y& Elsevier]

BACKGROUND AND AIMS: Liver metastases are the leading cause of death in colorectal cancer. To gain better insight into the biology of metastasis and possibly identify new therapeutic targets we systematically investigated liver-metastasis-specific molecular aberrations. METHODS: Primary colorectal cancer (pCRC) and matched liver metastases (LMs) from the same patients were analysed by microarray-based comparative genomic hybridisation in 21 pairs and gene expression profiling in 18 pairs. Publicly available databases were used to confirm findings in independent datasets. RESULTS: Chromosome aberration patterns and expression profiles of pCRC and matched LMs were strikingly similar. Unsupervised cluster analysis of genomic data showed that 20/21 pairs were more similar to each other than to any other analysed tumour. A median of only 11 aberrations per patient was found to be different between pCRC and LM, and expression of only 16 genes was overall changed upon metastasis. One region on chromosome band 11p15.5 showed a characteristic gain in LMs in 6/21 patients. This gain could be confirmed in an independent dataset of LMs (n=50). Localised within this region, the growth factor IGF2 (p=0.003) and the intestinal stem cell specific transcription factor ASCL2 (p=0.029) were found to be over-expressed in affected LM. Several ASCL2 target genes were upregulated in this subgroup of LM, including the intestinal stem cell marker OLFM4 (p=0.013). The correlation between ASCL2 expression and four known direct transcriptional targets (LGR5, EPHB3, ETS2 and SOX9) could be confirmed in an independent expression dataset (n=50). CONCLUSIONS: With unprecedented resolution a striking conservation of genomic alterations was demonstrated in liver metastases, suggesting that metastasis typically occurs after the pCRC has fully matured. In addition, we characterised a subset of liver metastases with an ASCL2-related stem-cell signature likely to affect metastatic behaviour of tumour cells. [ABSTRACT FROM AUTHOR]

目的:探讨5-脂氧合酶活化蛋白(FLAP)抑制剂MK886对人结肠癌细胞HT-29增殖的影响及其作用机制。方法分别采用12．5、25、50、75、100、200μmol/L的MK886干预体外培养的HT-29细胞，分别于干预24、48 h时采用CCK-8法测定细胞增殖抑制率，结果显示MK886抑制HT-29细胞增殖最佳作用时间为48 h、最佳浓度为48．12μmol/L。选择48．12μmol/L MK886干预HT-29细胞(MK886组)，另设对照组(不干预)，干预24 h时采用Real-time PCR技术检测Ascl2 mRNA表达，干预24、48、72 h时分别采用Western blotting 法检测 Ascl2 mRNA和蛋白表达。结果经过48．12μmol/L MK886干预24 h时HT-29细胞中Ascl2 mRNA相对表达量为0．35±0．02，对照组为0．72±0．02，两组比较P<0．01。48．12μmol/L MK886作用24、48、72 h时HT-29细胞中Ascl2蛋白相对表达量分别为1．75±0．13、1．10±0．15、0．71±0．19，均较对照组降低(P均<0．05)；且随着MK886作用时间延长， Ascl2蛋白相对表达量逐渐下调(P均<0．05)。结论 FLAP抑制剂MK886能抑制人结肠癌细胞HT-29增殖，其机制可能与下调Ascl2 mRNA和蛋白表达有关。 [ABSTRACT FROM AUTHOR]

Preimplantation development is a period of dynamic epigenetic change that begins with remodeling of egg and sperm genomes, and ends with implantation. During this time, parental-specific imprinting marks are maintained to direct appropriate imprinted gene expression. We previously demonstrated that H19 imprinting could be lost during preimplantation development under certain culture conditions. To define the lability of genomic imprints during this dynamic period and to determine whether loss of imprinting continues at later stages of development, imprinted gene expression and methylation were examined after in vitro preimplantation culture. Following culture in Whitten's medium, the normally silent paternal H19 allele was aberrantly expressed and undermethylated. However, only a subset of individual cultured blastocysts (∼65%) exhibited biallelic expression, while others maintained imprinted H19 expression. Loss of H19 imprinting persisted in mid-gestation conceptuses. Placental tissues displayed activation of the normally silent allele for H19, Ascl2, Snrpn, Peg3 and Xist while in the embryo proper imprinted expression for the most part was preserved. Loss of imprinted expression was associated with a decrease in methylation at the H19 and Snrpn imprinting control regions. These results indicate that tissues of trophectoderm origin are unable to restore genomic imprints and suggest that mechanisms that safeguard imprinting might be more robust in the embryo than in the placenta. [ABSTRACT FROM AUTHOR]

The basic helix–loop–helix (bHLH) transcription factors NEUROD1, NEUROD2 and ATH2 are expressed during first trimester human placental development. We determined the transactivation potential of each of these factors in trophoblasts by measuring changes in the endogenous gene activity using absolute quantification by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) after transient transfection. In these assays, NEUROD1 was found to transiently transactivate NEUROD2 in trophoblast cells. Promotor truncation assays, using luciferase constructs, showed the presence of two domains in the NEUROD2 promotor, which showed increased activity after NeuroD1 transfection. Each of these NeuroD1-responsive domains contains an E-box sequence. The NEUROD2 transactivation data fit with the spatial expression pattern of NEUROD1 and NEUROD2, since they are expressed in endovascular trophoblasts. This expression pattern, as well as the present transactivation results, might suggest the presence of a NEUROD differentiation cascade during first trimester human placental development. [Copyright &y& Elsevier]

During early human pregnancy, extravillous trophoblast cells invade the maternal tissue of the uterus in a way similar to invasion by cancer cells. However, the process of trophoblast invasion is regulated in a time and place restricted way, in contrast to cancer invasion. We screened first trimester placental tissue enriched by extravillous invasive trophoblasts for the expression of proneural basic helix–loop–helix (bHLH) transcription factors, which are important controllers of cell fate. Surprisingly, the presence of NEUROD1, NEUROD2 and ATH2 transcripts was found by reverse transcriptase polymerase chain reaction (RT-PCR) analysis in first trimester placentabed. Of these genes, the proneural genes NEUROD1 and NEUROD2 are expressed in different subsets of invasive trophoblasts. NEUROD1 expression is found in interstitial and endovascular invasive cells, while NEUROD2 expression is observed mainly in endovascular invasive cells, respectively. These data suggest that in addition to the involvement of proneural genes in neuron, neurendocrine and pancreas differentiation, these genes are involved in trophoblast differentation during progression of invasion. [Copyright &y& Elsevier]

Neural stem cells (NSCs) may offer beneficeial and promising adjuncts for treatment of neurological diseases such as Alzheimer's disease (AD), Parkinson's disease (PD) and spinal cord injuries. Previous studies showed that LncRNA FER1L4 plays crucial roles in many biological procedures such as invasion, metabolism, apoptosis, and stem cell differentiation. However, the role of FER1L4 in differentiation and growth of NSCs remains unknown. In the present research, we noted that FER1L4 is upregulated in NSCs induced with TNFα. Ectopic expression of FER1L4 suppresses NSCs proliferation and induces NSCs differentiated into neurons and astrocytes. Using Starbase online software, we identified that FER1L4 is one potential target gene of miR-874-3p. Ectopic expression of FER1L4 decreases miR-874-3p expression in NSCs. We identified Ascl2 is one target gene for miR-874-3p. Overexpression of FER1L4 enhances Ascl2 expression in NSCs. Furthermore, we proved that FER1L4 modulates the proliferation and differentiation of NSCs via regulating Ascl2., Competing Interests: None., (AJTR Copyright © 2022.)

Purpose Intestinal stem cell markers play a significant role in esophageal adenocarcinoma carcinogenesis via Barrett's esophagus; however, its utility as a prognostic biomarker has not been established. Methods We analyzed the immunohistochemical expression of intestinal stem cell markers, ASCL2 and LGR5, using whole slides (35 cases) and tissue microarray (TMA; 64 cases). On TMA slides, adjacent normal squamous epithelium, metaplastic glandular epithelium (Barrett's esophagus), and dysplastic glandular epithelium were inserted when applicable. Two pathologists semi-quantitatively scored stained slides independently, and the results were correlated with clinicopathologic factors and outcomes. Results In whole slides, 51% and 57% expressed high ASCL2 and high LGR5; in TMA, 69% and 88% expressed high ASCL2 and high LGR5, respectively. In TMA, high ASCL2 and low LGR5 expression significantly correlated to a higher number of involved lymph nodes (p=0.027 and p=0.0039), and LGR5 expression significantly correlated to the pathological stage (p=0.0032). Kaplan-Meier analysis showed a negative impact of high ASCL2 expression on overall survival (OS; WS p=0.0168, TMA p=0.0276) as well as progression-free survival (PFS; WS p=0.000638, TMA p=0.0466) but not LGR5. Multivariate Cox regression analysis revealed that ASCL2 expression is an independent prognostic factor for esophageal adenocarcinoma (OS; WS p=0.25, TMA p=0.011. PFS; WS p=0.012, TMA p=0.038). Analysis of the TCGA dataset showed that ASCL2 mRNA levels were correlated to nodal status but not overall survival. Conclusion High expression of the intestinal stem cell marker ASCL2 may predict unfavorable outcomes in surgically resected esophageal adenocarcinoma., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Shibahara et al.)

Simple Summary: Colorectal cancer remains a leading cause of cancer-related mortality worldwide. However, high-risk populations with a genetic predisposition for colorectal cancer could benefit greatly from novel and efficacious immunopreventive strategies that afford long-lasting protection. The achaete-scute family bHLH transcription factor 2 (Ascl2) has been identified as a promising target for immunoprevention of colorectal cancer, based on its induction during the formation and progression of colorectal tumors and its minimal expression observed in healthy tissue. The goal of the present study was to determine the efficacy of a protein-based vaccine targeting Ascl2 in combination with an anti-PD-1 treatment in a spontaneous colorectal cancer mouse model. This novel vaccine strategy promotes potent tumor-specific immunity, and prevents the formation of colon adenomas in mice. The results demonstrate that Ascl2 is a promising target for immunoprevention for individuals at elevated risk of developing colorectal cancer. Novel immunopreventive strategies are emerging that show great promise for conferring long-term protection to individuals at high risk of developing colorectal cancer. The KISIMA vaccine platform utilizes a chimeric protein comprising: (1) a selected tumor antigen; (2) a cell-penetrating peptide to improve antigen delivery and epitope presentation, and (3) a TLR2/4 agonist to serve as a self-adjuvant. This study examines the ability of a KISIMA vaccine against achaete-scute family bHLH transcription factor 2 (Ascl2), an early colon cancer antigen, to reduce colon tumor formation by stimulating an anti-tumor immune response. Vaccine administrations were well-tolerated and led to circulating antibodies and antigen-specific T cells in a mouse model of colorectal cancer. To assess preventive efficacy, the vaccine was administered to mice either alone or in combination with the immune checkpoint inhibitor anti-PD-1. When delivered to animals prior to colon tumor formation, the combination strategy significantly reduced the development of colon microadenomas and adenomas, as compared to vehicle-treated controls. This response was accompanied by an increase in the intraepithelial density of CD3+ T lymphocytes. Together, these data indicate that the KISIMA-Ascl2 vaccine shows great potential to be a safe and potent immunopreventive intervention for individuals at high risk of developing colorectal cancer. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is the third most common cancer, according to recently published literature. While the incidence and the mortality of CRC has decreased due to effective cancer screening measures, there has been an increase in the number of young patients diagnosed with colon cancer due to unclear reasons. As a target molecule of the Wnt signaling pathway, Ascl2 is an important marker of CRC stem cells and plays an important role in maintaining the nature of colon cancer stem/precursor cells. However, the role of Ascl2 in autophagy in CRC cells is rarely elucidated., Methods: In this study, we found that Ascl2 was increased in CRC compared with adjacent tissue. Downregulation of Ascl2 in CRC cells could suppress proliferation and invasion, and induce apoptosis, of CRC cells. Moreover, we found that autophagy-relative protein LC3 increased after Ascl2 knockdown. Furthermore, we treated CRC cells with autophagy inhibitors 3-MA (3-Methyladenine) and CQ (Chloroquine)., Results: The results showed that autophagy inhibitors could prevent apoptosis, which was induced by Ascl2 knockdown. Finally, we confirmed that the downregulation of Ascl2 in CRC cells could alleviate the pathological process in vivo by xenograft experiment., Conclusions: Our findings indicated that si-Ascl2 (small/short interfering) exerted a tumor suppression function in CRC by inducing autophagic cell death, and suggest that Ascl2 targeted therapy represents a novel strategy for CRC treatment., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/jgo-21-183). The authors have no conflicts of interest to declare., (2021 Journal of Gastrointestinal Oncology. All rights reserved.)

The gene family with sequence similarity 13 member A (FAM13A) has recently been identified as a marker gene in insulin sensitivity and lipolysis. In this study, we first analyzed the expression patterns of this gene in different tissues of adult cattle and then constructed a phylogenetic tree based on the FAM13A amino acid sequence. This showed that subcutaneous adipose tissue had the highest expression in all tissues except lung tissue. Then we summarized the gene structure. The promoter region sequence of the gene was successfully amplified, and the −241/+54 region has been identified as the core promoter region. The core promoter region was determined by the unidirectional deletion of the 5' flanking promoter region of the FAM13A gene. Based on the bioinformatics analysis, we examined the dual luciferase activity of the vector constructed by the mutation site, and the transcription factors ACSL1 and ASCL2 were found as transcriptional regulators of FAM13A. Moreover, electrophoretic mobility shift assay (EMSA) further validated the regulatory role of ACSL1 and ASCL2 in the regulation of FAM13A. ACSL1 and ASCL2 were finally identified as activating transcription factors. Our results provide a basis for the function of the FAM13A gene in bovine adipocytes in order to improve the deposition of fat deposition in beef cattle muscle. [ABSTRACT FROM AUTHOR]