The cAMP/PKA/CREB and TGFβ/SMAD4 Pathways Regulate Stemness and Metastatic Potential in Colorectal Cancer Cells

Disruption of oncogenic pathways in mucoepidermoid carcinoma: CREB inhibitor 666.15 as a potential therapeutic agent

OBJECTIVES

Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland tumour with around 50 % of cases carrying the CRTC1-MAML2 translocation. The CREB pathway has been associated with the transforming activity of this translocation. The aim of this study was to determine the effects of CREB inhibition on MEC cell behaviour in vitro.

MATERIAL AND METHODS

Two translocation-positive (UM-HMC-2 and H292) and one translocation-negative (H253) MEC cell lines were treated with 666.15, a CREB inhibitor. Drug IC50 doses were determined for each cell line. Clonogenic and spheroid assays were used to assess survival, including percentage of cancer stem cells, and transwell and scratch assays evaluated invasive and migratory capacities, respectively. Immunofluorescence staining was used to determine E-cadherin expression.

RESULTS

CREB inhibition significantly reduced the number of surviving colonies and spheroids and delayed cell invasion in all cell lines, but this was more significant in the fusion positive, UM-HMC-2 cells. The expression of E-cadherin was significantly higher in treated UM-HMC-2 and H292 cells.

CONCLUSION

CREB inhibition with 666.15 impaired key MEC oncogenic behaviours associated with metastasis and drug resistance, including cell invasion and survival.

Lactylation drives hCG-triggered luteinization in hypoxic granulosa cells

Hypoxia that occurs during the luteinization process of granulosa cells (GC) contributes to the formation of lactate in follicles. Lysine lactylation (Kla), a post-translational modification directly regulated by lactate levels, is a metabolic sensor that converts metabolic information into gene expression patterns. In this study, we employed human chorionic gonadotropin (hCG) to induce GCs luteinization and discovered that hypoxia enhances hCG-mediated GCs luteinization by stimulating lactate production/lactylation. The elevated levels of luteinization markers (including progesterone synthesis, expression of CYP11A1 and STAR) were accompanied by increased lactate production as well as enhanced lactylation in mouse ovarian GCs after the injection of hCG in vivo. By treating GCs with hypoxia in vitro, we found that hypoxia accelerated hCG-induced GCs luteinization, which was inhibited after blocking lactate production/lactylation. Further investigations revealed that H3K18la might contribute to hCG-induced luteinization in hypoxic GCs by upregulating CYP11A1 and STAR transcription. Additionally, we identified that CREB K136la is also required for hCG-induced GCs luteinization under hypoxia. Finally, the in vitro findings were verified in vivo, which showed impaired GCs luteinization and corpus luteum formation after blocking the lactate/lactylation by intraperitoneal injection of oxamate/C646 in mice. Taken together, this study uncovered a novel role of protein lactylation in the regulation of GCs luteinization.

Integrated multi-omics characterization of SMAD4 mutant colorectal cancer

Colorectal cancer is one of the most common cancers around the world, which is a severe threat to people's health. SMAD4 belongs to the dwarfin/SMAD family, which plays a crucial role in TGF-β and BMP signal pathways. As the molecular characterization of colon cancer patients following SMAD4 mutations remains unclear, we integrated multi-omics data of SMAD4 mutant patients to reveal the profile of molecular characterization of SMAD4 mutation. A missense mutation is the most common mutant type of SMAD4. Patients with SMAD4 mutation had worse survival. Tumor tissues from patients carrying the SMAD4 mutation showed a reduction in various immune cells, such as CD4 + memory T cells and memory B cells. Many differential genes were identified compared to the SMAD4 mutation-free group and could be significantly enriched for tumor- and immune-related signaling pathways. In addition, the mutant group had different drug sensitivities than the non-mutant group.

A functional variant rs10409772 in FUT6 promoter regulates colorectal cancer progression through PKA/CREB signaling

Fucosyltransferase 6 (FUT6) is overexpressed in colorectal cancer tissue according to TCGA samples and immunohistochemistry results of a tissue microarray. FUT6 effects cell migration, tumor formation and proliferation of colorectal cancer cells in different essays. FUT6 promotes cancer cell proliferation in vitro and colorectal tumorigenesis in vivo by upregulating PKA/CREB pathway activation. Moreover, FUT6 expression is regulated by rs10409772 shown in the luciferase essays, a single nucleotide polymorphism in the promoter of FUT6. Our study suggests that elevated expression of FUT6 promotes PKA/CREB signaling, which in turn augments colorectal carcinogenesis, indicating a potential therapeutic target for colorectal cancer patients with increased FUT6 expression.

Recent advances and molecular mechanisms of TGF-β signaling in colorectal cancer, with focus on bioactive compounds targeting

Colorectal cancer (CRC) is one of the most significant forms of human cancer. It is characterized by its heterogeneity because several molecular factors are involved in contiguity and can link it to others without having a linear correlation. Among the factors influencing tumor transformation in CRC, transforming growth factor-beta (TGF-β) plays a key promoter role. This factor is associated with human colorectal tumors with a very high prognosis: it increases the survival, invasion, and metastasis of CRC cells, thus functioning as an oncogene. The inhibition of this factor can constitute a major therapeutic route for CRC treatment. Various chemical drugs including synthetic molecules and biotherapies have been developed as TGF-β inhibitors. Moreover, the scientific community has recently shown a major interest in screening natural drugs inhibiting TGF-β in CRC. In this context, we carried out this review article using computerized databases, such as PubMed, Google Scholar, Springer Link, Science Direct, Cochrane Library, Embase, Web of Science, and Scopus, to highlight the molecular mechanism of TGF-β in CRC induction and progression and current advances in the pharmacodynamic effects of natural bioactive substances targeting TGF-β in CRC.

Liver tropism of ER mutant breast cancer is characterized by unique molecular changes and immune infiltration

PURPOSE

Hotspot estrogen receptor alpha (ER/ESR1) mutations are recognized as the driver for both endocrine resistance and metastasis in advanced ER-positive (ER+) breast cancer, but their contributions to metastatic organ tropism remain insufficiently understood. In this study, we aim to comprehensively profile the organotropic metastatic pattern for ESR1 mutant breast cancer.

METHODS

The organ-specific metastatic pattern of ESR1 mutant breast cancer was delineated using multi-omics data from multiple publicly available cohorts of ER+ metastatic breast cancer patients. Gene mutation/copy number variation (CNV) and differential gene expression analyses were performed to identify the genomic and transcriptomic alterations uniquely associated with ESR1 mutant liver metastasis. Upstream regulator, downstream pathway, and immune infiltration analysis were conducted for subsequent mechanistic investigations.

RESULTS

ESR1 mutation-driven liver tropism was revealed by significant differences, encompassing a higher prevalence of liver metastasis in patients with ESR1 mutant breast cancer and an enrichment of mutations in liver metastatic samples. The significant enrichment of AGO2 copy number amplifications (CNAs) and multiple gene expression changes were revealed uniquely in ESR1 mutant liver metastasis. We also unveiled alterations in downstream signaling pathways and immune infiltration, particularly an enrichment of neutrophils, suggesting potential therapeutic vulnerabilities.

CONCLUSION

Our data provide a comprehensive characterization of the behaviors and mechanisms of ESR1 mutant liver metastasis, paving the way for the development of personalized therapy to target liver metastasis for patients with ESR1 mutant breast cancer.

Cordycepin Triphosphate as a Potential Modulator of Cellular Plasticity in Cancer via cAMP-Dependent Pathways: An In Silico Approach

Cordycepin, or 3'-deoxyadenosine, is an adenosine analog with a broad spectrum of biological activity. The key structural difference between cordycepin and adenosine lies in the absence of a hydroxyl group at the 3' position of the ribose ring. Upon administration, cordycepin can undergo an enzymatic transformation in specific tissues, forming cordycepin triphosphate. In this study, we conducted a comprehensive analysis of the structural features of cordycepin and its derivatives, contrasting them with endogenous purine-based metabolites using chemoinformatics and bioinformatics tools in addition to molecular dynamics simulations. We tested the hypothesis that cordycepin triphosphate could bind to the active site of the adenylate cyclase enzyme. The outcomes of our molecular dynamics simulations revealed scores that are comparable to, and superior to, those of adenosine triphosphate (ATP), the endogenous ligand. This interaction could reduce the production of cyclic adenosine monophosphate (cAMP) by acting as a pseudo-ATP that lacks a hydroxyl group at the 3' position, essential to carry out nucleotide cyclization. We discuss the implications in the context of the plasticity of cancer and other cells within the tumor microenvironment, such as cancer-associated fibroblast, endothelial, and immune cells. This interaction could awaken antitumor immunity by preventing phenotypic changes in the immune cells driven by sustained cAMP signaling. The last could be an unreported molecular mechanism that helps to explain more details about cordycepin's mechanism of action.

Activin and Hepatocyte Growth Factor Promotes Colorectal Cancer Stemness and Metastasis through FOXM1/SOX2/CXCR4 Signaling

Background/Aims

Cancer stem cells (CSCs) are believed to drive tumor development and metastasis. Activin and hepatocyte growth factor (HGF) are important cytokines with the ability to induce cancer stemness. However, the effect of activin and HGF combination treatment on CSCs is still unclear.

Methods

In this study, we sequentially treated colorectal cancer cells with activin and HGF and examined CSC marker expression, self-renewal, tumorigenesis, and metastasis. The roles of forkhead box M1 (FOXM1) and sex-determining region Y-box 2 (SOX2), two stemness-related transcription factors, in activin/HGF-induced aggressive phenotype were explored.

Results

Activin and HGF treatment increased the expression of CSC markers and enhanced sphere formation in colorectal cancer cells. The tumorigenic and metastatic capacities of colorectal cancer cells were enhanced upon activin and HGF treatment. Activin and HGF treatment preferentially promoted stemness and metastasis of CD133+ subpopulations sorted from colorectal cancer cells. FOXM1 was upregulated by activin and HGF treatment, and the knockdown of FOXM1 blocked activin/HGF-induced stemness, tumorigenesis, and metastasis of colorectal cancer cells. Similarly, SOX2 was silencing impaired sphere formation of activin/HGF-treated colorectal cancers. Overexpression of SOX2 rescued the stem cell-like phenotype in FOXM1-depleted colorectal cancer cells with activin and HGF treatment. Additionally, the inhibition of FOXM1 via thiostrepton suppressed activin/HGF-induced stemness, tumorigenesis and metastasis.

Conclusions

Sequential treatment with activin and HGF promotes colorectal cancer stemness and metastasis through activation of the FOXM1/SOX2 signaling. FOXM1 could be a potential target for the treatment of colorectal cancer metastasis.

Identification of DNA methylation characteristics associated with metastasis and prognosis in colorectal cancer

Colorectal cancer (CRC) is prone to metastasis and recurrence after surgery, which is one of the main causes for its poor treatment and prognosis. Therefore, it is essential to identify biomarkers associated with metastasis and recurrence in CRC. DNA methylation has a regulatory role in cancer metastasis, tumor immune microenvironment (TME), and prognosis and may be one of the most valuable biomarkers for predicting CRC metastasis and prognosis. We constructed a diagnostic model and nomogram that can effectively predict CRC metastasis based on the differential methylation CpG sites (DMCs) between metastatic and non-metastatic CRC patients. Then, we identified 17 DMCs associated with progression free survival (PFS) of CRC and constructed a prognostic model. The prognosis model based on 17 DMCs can predict the PFS of CRC with medium to high accuracy. The results of immunohistochemical analysis indicated that the protein expression levels of the genes involved in prognostic DMCs were different between normal and colorectal cancer tissues. According to the results of immune-related analysis, we found that the low-risk patients had better immunotherapy response. In addition, high risk scores were negatively correlated with high tumor mutation burden (TMB) levels, and patients with low TMB levels in the high-risk group had the worst PFS. Our work shows the clinical value of DNA methylation in predicting CRC metastasis and PFS, as well as their correlation with TME, immunotherapy, and TMB, which helps understand the changes of DNA methylation in CRC metastasis and improving the treatment and prognosis of CRC.

TGF-β signaling promotes desmoid tumor formation via CSRP2 upregulation

Desmoid tumors (DTs), also called desmoid-type fibromatoses, are locally aggressive tumors of mesenchymal origin. In the present study, we developed a novel mouse model of DTs by inducing a local mutation in the Ctnnb1 gene, encoding β-catenin in PDGFRA-positive stromal cells, by subcutaneous injection of 4-hydroxy-tamoxifen. Tumors in this model resembled histologically clinical samples from DT patients and showed strong phosphorylation of nuclear SMAD2. Knockout of SMAD4 in the model significantly suppressed tumor growth. Proteomic analysis revealed that SMAD4 knockout reduced the level of Cysteine-and-Glycine-Rich Protein 2 (CSRP2) in DTs, and treatment of DT-derived cells with a TGF-β receptor inhibitor reduced CSRP2 RNA levels. Knockdown of CSRP2 in DT cells significantly suppressed their proliferation. These results indicate that the TGF-β/CSRP2 axis is a potential therapeutic target for DTs downstream of TGF-β signaling.

cAMP-PKA/EPAC signaling and cancer: the interplay in tumor microenvironment

Cancer is a complex disease resulting from abnormal cell growth that is induced by a number of genetic and environmental factors. The tumor microenvironment (TME), which involves extracellular matrix, cancer-associated fibroblasts (CAF), tumor-infiltrating immune cells and angiogenesis, plays a critical role in tumor progression. Cyclic adenosine monophosphate (cAMP) is a second messenger that has pleiotropic effects on the TME. The downstream effectors of cAMP include cAMP-dependent protein kinase (PKA), exchange protein activated by cAMP (EPAC) and ion channels. While cAMP can activate PKA or EPAC and promote cancer cell growth, it can also inhibit cell proliferation and survival in context- and cancer type-dependent manner. Tumor-associated stromal cells, such as CAF and immune cells, can release cytokines and growth factors that either stimulate or inhibit cAMP production within the TME. Recent studies have shown that targeting cAMP signaling in the TME has therapeutic benefits in cancer. Small-molecule agents that inhibit adenylate cyclase and PKA have been shown to inhibit tumor growth. In addition, cAMP-elevating agents, such as forskolin, can not only induce cancer cell death, but also directly inhibit cell proliferation in some cancer types. In this review, we summarize current understanding of cAMP signaling in cancer biology and immunology and discuss the basis for its context-dependent dual role in oncogenesis. Understanding the precise mechanisms by which cAMP and the TME interact in cancer will be critical for the development of effective therapies. Future studies aimed at investigating the cAMP-cancer axis and its regulation in the TME may provide new insights into the underlying mechanisms of tumorigenesis and lead to the development of novel therapeutic strategies.

Prolonged exposure of environmental concentration benzo[a]pyrene promoted cancer stemness through AhR/PKA/SOX2 dependent pathway in small cell lung cancer

Benzo[a]pyrene (BaP) is commonly found in the environment as a result of incomplete combustion of organic materials and cigarette smoke. Epidemiological studies have consistently suggested that elderly smokers are at higher risk for small cell lung cancer (SCLC), with risks and clinical stages increasing with the intensity and duration of smoking. However, the underlying mechanism remains insufficiently investigated. Here, we established a positive correlation between smoking and BaP metabolite 3-hydroxybenzo[a]pyrene (3OH-BaP) in urine. The pooled standardized mean difference of urinary 3OH-BaP concentration for smokers versus nonsmokers was 5.18 (95 % CI 2.86-7.50). Clinical data suggested that smoking led to more lymph node metastasis, higher pathological N-stage, and worse overall survival in SCLC patients. We identified 75 genes that participate in BaP-associated cancer stemness of SCLC from Comparative Toxicogenomics Database and validated the expression of these candidate genes in SCLC patient samples. Protein kinase cAMP-activated catalytic subunit alpha (PRKACA) was found to be most upregulated in SCLC patients and in vitro experiments indicated that long-term exposure of SCLC cells to BaP, at the concentration equivalent to those detected in blood, increased PKA protein level. Further investigation revealed that PKA could directly interact with SOX2 and protect SOX2 from COP1-mediated ubiquitination and degradation. Upregulated SOX2 then contributed to the stemness and metastasis of SCLC cells while inhibition of aryl hydrocarbon receptor (AhR) signaling pathway abolished BaP induced PKA expression and downstream PKA/SOX2 axis. Our findings firstly pinpoint BaP exposure as a high-risk factor for SCLC and worse outcomes in patients, with the underlying mechanism being the activation of cancer stemness of SCLC via the AhR/PKA/SOX2 axis.

ATP ion channel P2X7 receptor as a regulatory molecule in the progression of colorectal cancer

Large amounts of adenosine triphosphate (ATP), a natural P2X7 receptor activator, are released during colorectal carcinogenesis. P2X7 receptor activation regulates the activity of colorectal cancer (CRC) cells by mediating intracellular signal transduction. Importantly, the opening and activation of membrane pores of P2X7 receptor are different, which can play a dual role in promoting or inhibiting the progression of CRC. These can also depend on P2X7 receptor to regulate the activities of immune cells in the microenvironment, play the functions of immune regulation, immune escape and immune monitoring. While the use of P2X7 receptor antagonists (such as BBG, A438079 and A740003) can play a certain inhibitory pharmacological role on the activity of CRC. Therefore, in this paper, the mechanism and immunomodulatory function of P2X7 receptor involved in the progression of CRC were discussed. Moreover, we discussed the effect of antagonizing the activity of P2X7 receptor on the progression of CRC. So P2X7 receptor may be a new pharmacological molecular target for the treatment of CRC.

Inhibition of PKA/CREB1 pathway confers sensitivity to ferroptosis in non-small cell lung cancer

Ferroptosis is a type of regulated cell death characterized by iron accumulation and lipid peroxidation. The molecular mechanisms underlying ferroptosis regulation in non-small cell lung cancer (NSCLC) are poorly understood. In this study, we found that protein kinase A (PKA) inhibition enhanced ferroptosis susceptibility in NSCLC cells, as evidenced by reduced cell viability and increased lipid peroxidation. We further identified cAMP-responsive element protein 1 (CREB1), a transcription factor and a substrate of PKA, as a key regulator of ferroptosis. Knockdown of CREB1 sensitized NSCLC cells to ferroptosis inducers (FINs) and abolished the effects of PKA inhibitor and agonist, revealing the pivotal role of CREB1 in ferroptosis regulation. Using a high-throughput screening approach and subsequent validation by chromatin immunoprecipitation (ChIP) and dual-luciferase assays, we discovered that CREB1 transcriptionally activated stearoyl-CoA desaturase (SCD), an enzyme that catalyzes the conversion of saturated fatty acids to monounsaturated fatty acids. SCD conferred ferroptosis resistance by decreasing the availability of polyunsaturated fatty acids for lipid peroxidation, and its overexpression rescued the effect of CREB1 knockdown on ferroptosis in vitro. Besides, CREB1 knockdown suppressed xenograft tumor growth in the presence of Imidazole Ketone Erastin (IKE), a potent FIN, and this effect was reversed by SCD. Finally, we showed that high expression of CREB1 was associated with poor prognosis in NSCLC patients from public datasets and our institution. Collectively, this study illustrates the effect of PKA/CREB1/SCD axis in regulating ferroptosis of NSCLC, targeting this pathway may provide new strategies for treating NSCLC patients.

CircLDLRAD3 inhibits Oral squamous cell carcinoma progression by regulating miR-558/Smad4/TGF-β

Oral squamous cell carcinoma (OSCC) is a malignant neoplasm with high mortality and morbidity. The role of circRNA and its molecular mechanism in OSCC remains largely unknown. The study aims to explore the role of a novel circular RNA (circLDLRAD3) in OSCC and its underlying mechanism. PCR and fluorescence in situ hybridization were used to explore the expression features of circLDLRAD3 in OSCC. The effects of circLDLRAD3 on the behaviour of OSCC were investigated using CCK-8, colony formation assay, transwell and animal experiments. Bioinformatics analysis along with dual luciferase reporter assay and RIP assay were used to reveal the interaction between circLDLRAD3, miR-558 and Smad4. It was revealed that circLDLRAD3 exhibited low expression status in OSCC. CircLDLRAD3 inhibits proliferation, migration, and invasion of OSCC cells both in vitro and in vivo. Mechanistically, circLDLRAD3 could bind with miR-558 to positively regulate its target gene Smad4 expression. Rescue experiments further confirmed both miR-558 overexpression and Smad4 knockdown could reverse the influence of circLDLRAD3 on OSCC phenotypes. Moreover, circLDLRAD3 regulate the TGF-β signalling pathways to influence EMT through miR-558/Smad4 axis. Our study found that circLDLRAD3 is downregulated in OSCC and verified its tumour suppressor function and mechanism in OSCC through sponging miR-558 to regulate miR-558/Smad4/TGF-β axis. The characterization of such regulating network uncovers an important mechanism underlying OSCC progression, which could provide promising targets targeted therapy strategies for OSCC in the future.

A potential novel biomarker: comprehensive analysis of prognostic value and immune implication of CES3 in colonic adenocarcinoma

PURPOSE

Colon cancer is the most common malignant tumor in the intestine. Abnormal Carboxylesterases 3 (CES3) expression had been reported to be correlated to multiple tumor progression. However, the association among CES3 expression and prognostic value and immune effects in colonic adenocarcinoma (COAD) were unclear.

PATIENTS AND METHODS

The transcription and expression data of CES3 and corresponding clinical information was downloaded from The Cancer Genome Atlas (TCGA). The CES3 protein expression and the prognostic value were verified based on tissue microarray data. The Cancer immune group Atlas (TCIA), Tumor Immune Dysfunction and Exclusion (TIDE) algorithm and the GSE78220 immunotherapy cohort were used to forecast immunotherapy efficacy. Finally, a prognostic immune signature was constructed and verified.

RESULTS

Compared with normal colon tissues, the expression of mRNA and protein levels of CES3 were downregulated in tumor tissues. CES3 expression was associated with TIICs. Hihg-CES3 COAD patients had better efficacy of concurrent immunotherapy. CES3-related immune genes (CRIs) were identified and were then used to construct prognostic immune signature and had been successfully verified in GES39582.

CONCLUSION

CES3 might be a potential immune-related gene and promising prognostic biomarker in COAD.

Decreased liver B vitamin-related enzymes as a metabolic hallmark of cancer cachexia

Cancer cachexia is a complex metabolic disorder accounting for ~20% of cancer-related deaths, yet its metabolic landscape remains unexplored. Here, we report a decrease in B vitamin-related liver enzymes as a hallmark of systemic metabolic changes occurring in cancer cachexia. Metabolomics of multiple mouse models highlights cachexia-associated reductions of niacin, vitamin B6, and a glycine-related subset of one-carbon (C1) metabolites in the liver. Integration of proteomics and metabolomics reveals that liver enzymes related to niacin, vitamin B6, and glycine-related C1 enzymes dependent on B vitamins decrease linearly with their associated metabolites, likely reflecting stoichiometric cofactor-enzyme interactions. The decrease of B vitamin-related enzymes is also found to depend on protein abundance and cofactor subtype. These metabolic/proteomic changes and decreased protein malonylation, another cachexia feature identified by protein post-translational modification analysis, are reflected in blood samples from mouse models and gastric cancer patients with cachexia, underscoring the clinical relevance of our findings.

Multi-target reconstruction based on subspace decision optimization for bioluminescence tomography

BACKGROUND AND OBJECTIVE

Bioluminescence tomography (BLT) is a noninvasive optical imaging technique that provides qualitative and quantitative information on the spatial distribution of tumors in living animals. Researchers have proposed a list of algorithms and strategies for BLT reconstruction to improve its reconstruction quality. However, multi-target BLT reconstruction remains challenging in practical clinical applications due to the mutual interference of optical signals and difficulty in source separation.

METHODS

To solve this problem, this study proposes the subspace decision optimization (SDO) approach based on the traditional iterative permissible region strategy. The SDO approach transforms a single permissible region into multiple subspaces by clustering analysis. These subspaces are shrunk based on subspace shrinking optimization to achieve spatial continuity of the permissible regions. In addition, these subspaces are merged to construct a new permissible region and then the next iteration of reconstruction is carried out to ensure the stability of the results. Finally, all the iterative results are optimized based on the normal distribution model and the distribution properties of the targets to ensure the sparsity of each target and the non-biasing of the overall results.

RESULTS

Experimental results show that the SDO approach can automatically identify and separate different targets, ensuring the accuracy and quality of multi-target BLT reconstruction results. Meanwhile, SDO can combine various types of reconstruction algorithms and provide stable and high-quality reconstruction results independent of the algorithm parameters.

CONCLUSIONS

The SDO approach provides an integrated solution to the multi-target BLT reconstruction problem, realizing the whole process including target recognition, separation, reconstruction, and result enhancement, which can extend the application domain of BLT.

Phytochemicals targeting glycolysis in colorectal cancer therapy: effects and mechanisms of action

Colorectal cancer (CRC) is the third most common malignant tumor in the world, and it is prone to recurrence and metastasis during treatment. Aerobic glycolysis is one of the main characteristics of tumor cell metabolism in CRC. Tumor cells rely on glycolysis to rapidly consume glucose and to obtain more lactate and intermediate macromolecular products so as to maintain growth and proliferation. The regulation of the CRC glycolysis pathway is closely associated with several signal transduction pathways and transcription factors including phosphatidylinositol 3-kinases/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR), adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), hypoxia-inducible factor-1 (HIF-1), myc, and p53. Targeting the glycolytic pathway has become one of the key research aspects in CRC therapy. Many phytochemicals were shown to exert anti-CRC activity by targeting the glycolytic pathway. Here, we review the effects and mechanisms of phytochemicals on CRC glycolytic pathways, providing a new method of drug development.

Cancer cell employs a microenvironmental neural signal trans-activating nucleus-mitochondria coordination to acquire stemness

Cancer cell receives extracellular signal inputs to obtain a stem-like status, yet how tumor microenvironmental (TME) neural signals steer cancer stemness to establish the hierarchical tumor architectures remains elusive. Here, a pan-cancer transcriptomic screening for 10852 samples of 33 TCGA cancer types reveals that cAMP-responsive element (CRE) transcription factors are convergent activators for cancer stemness. Deconvolution of transcriptomic profiles, specification of neural markers and illustration of norepinephrine dynamics uncover a bond between TME neural signals and cancer-cell CRE activity. Specifically, neural signal norepinephrine potentiates the stemness of proximal cancer cells by activating cAMP-CRE axis, where ATF1 serves as a conserved hub. Upon activation by norepinephrine, ATF1 potentiates cancer stemness by coordinated trans-activation of both nuclear pluripotency factors MYC/NANOG and mitochondrial biogenesis regulators NRF1/TFAM, thereby orchestrating nuclear reprograming and mitochondrial rejuvenating. Accordingly, single-cell transcriptomes confirm the coordinated activation of nuclear pluripotency with mitochondrial biogenesis in cancer stem-like cells. These findings elucidate that cancer cell acquires stemness via a norepinephrine-ATF1 driven nucleus-mitochondria collaborated program, suggesting a spatialized stemness acquisition by hijacking microenvironmental neural signals.

Chemotherapy-induced executioner caspase activation increases breast cancer malignancy through epigenetic de-repression of CDH12

Cancer relapse and metastasis are major obstacles for effective treatment. One important mechanism to eliminate cancer cells is to induce apoptosis. Activation of executioner caspases is the key step in apoptosis and was considered "a point of no return". However, in recent years, accumulating evidence has demonstrated that cells can survive executioner caspase activation in response to apoptotic stimuli through a process named anastasis. Here we show that breast cancer cells that have survived through anastasis (anastatic cells) after exposure to chemotherapeutic drugs acquire enhanced proliferation and migration. Mechanistically, cadherin 12 (CDH12) is persistently upregulated in anastatic cells and promotes breast cancer malignancy via activation of ERK and CREB. Moreover, we demonstrate that executioner caspase activation induced by chemotherapeutic drugs results in loss of DNA methylation and repressive histone modifications in the CDH12 promoter region, leading to increased CDH12 expression. Our work unveils the mechanism underlying anastasis-induced enhancement in breast cancer malignancy, offering new therapeutic targets for preventing post-chemotherapy cancer relapse and metastasis.

Tumor microenvironment in ovarian cancer peritoneal metastasis

Ovarian cancer (OC) is one of the most common gynecological malignancies with high morbidity and mortality. The peritoneum is one of the most common metastatic sites in ovarian cancer, involving large amounts of ascites. However, its mechanism is unclear. The peritoneal microenvironment composed of peritoneal effusion and peritoneum creates favorable conditions for ovarian cancer progression and metastasis. Here, we reviewed the peritoneal metastasis patterns and molecular mechanisms of ovarian cancer, as well as major components of the peritoneal microenvironment, peritoneal effusion, and immune microenvironment, and investigated the relationship between the peritoneal microenvironment and ovarian cancer metastasis.

TGF-β Signaling in Metastatic Colorectal Cancer (mCRC): From Underlying Mechanism to Potential Applications in Clinical Development

Colorectal cancer (CRC) is a serious public health issue, and it has the leading incidence and mortality among malignant tumors worldwide. CRC patients with metastasis in the liver, lung or other distant sites always have poor prognosis. Thus, there is an urgent need to discover the underlying mechanisms of metastatic colorectal cancer (mCRC) and to develop optimal therapy for mCRC. Transforming growth factor-β (TGF-β) signaling plays a significant role in various physiologic and pathologic processes, and aberrant TGF-β signal transduction contributes to mCRC progression. In this review, we summarize the alterations of the TGF-β signaling pathway in mCRC patients, the functional mechanisms of TGF-β signaling, its promotion of epithelial-mesenchymal transition, its facilitation of angiogenesis, its suppression of anti-tumor activity of immune cells in the microenvironment and its contribution to stemness of CRC cells. We also discuss the possible applications of TGF-β signaling in mCRC diagnosis, prognosis and targeted therapies in clinical trials. Hopefully, these research advances in TGF-β signaling in mCRC will improve the development of new strategies that can be combined with molecular targeted therapy, immunotherapy and traditional therapies to achieve better efficacy and benefit mCRC patients in the near future.