A wound-healing program is hijacked to promote cancer metastasis

Somatic gain-of-function mutations in BUD13 promote oncogenesis by disrupting Fbw7 function

Somatic mutations occurring on key enzymes are extensively studied and targeted therapies are developed with clinical promises. However, context-dependent enzyme function through distinct substrates complicated targeting a given enzyme. Here, we develop an algorithm to elucidate a new class of somatic mutations occurring on enzyme-recognizing motifs that cancer may hijack to facilitate tumorigenesis. We validate BUD13-R156C and -R230Q mutations evading RSK3-mediated phosphorylation with enhanced oncogenicity in promoting colon cancer growth. Further mechanistic studies reveal BUD13 as an endogenous Fbw7 inhibitor that stabilizes Fbw7 oncogenic substrates, while cancerous BUD13-R156C or -R230Q interferes with Fbw7Cul1 complex formation. We also find this BUD13 regulation plays a critical role in responding to mTOR inhibition, which can be used to guide therapy selections. We hope our studies reveal the landscape of enzyme-recognizing motif mutations with a publicly available resource and provide novel insights for somatic mutations cancer hijacks to promote tumorigenesis with the potential for patient stratification and cancer treatment.

Biology of cancer; from cellular and molecular mechanisms to developmental processes and adaptation

Cancer research has been largely focused on the cellular and molecular levels of investigation. Recent data show that not only the cell but also the extracellular matrix plays a major role in the progression of malignancy. In this way, the cells and the extracellular matrix create a specific local microenvironment that supports malignant development. At the same time, cancer implies a systemic evolution which is closely related to developmental processes and adaptation. Consequently, there is currently a real gap between the local investigation of cancer at the microenvironmental level, and the pathophysiological approach to cancer as a systemic disease. In fact, the cells and the matrix are not only complementary structures but also interdependent components that act synergistically. Such relationships lead to cell-matrix integration, a supracellular form of biological organization that supports tissue development. The emergence of this supracellular level of organization, as a structure, leads to the emergence of the supracellular control of proliferation, as a supracellular function. In humans, proliferation is generally involved in developmental processes and adaptation. These processes suppose a specific configuration at the systemic level, which generates high-order guidance for local supracellular control of proliferation. In conclusion, the supracellular control of proliferation act as an interface between the downstream level of cell division and differentiation, and upstream level of developmental processes and adaptation. Understanding these processes and their disorders is useful not only to complete the big picture of malignancy as a systemic disease, but also to open new treatment perspectives in the form of etiopathogenic (supracellular or informational) therapies.

Aging Impairs the Cellular Interplay between Myeloid Cells and Mesenchymal Cells during Skin Healing in Mice

Impaired wound healing is a major issue in the elderly population and is associated with substantial health and economic burden, which is exponentially increasing with the growing aging population. While the underlying pathobiology of disturbed skin healing by aging is linked to several genetic and epigenetic factors, little is known about the cell-cell interaction during the wound healing process in aged individuals, particularly the mesenchymal stem cell (MSCs)-macrophages axis. In this study, by using a thermal injury animal model in which we compared the wound healing process of adult and young mice, we found that the insufficient pool of MSCs in adult animals are deficient in migrating to the wound bed and instead are restricted to the wound edge. We identified a deficiency of a CD90-positive MSC subpopulation in the wounds of adult animals, which is positively correlated with the number of F4/80+ macrophages. In vitro, we found that CD90+ cells preferentially adhere to the myeloid cells forming doublet cells. Thus, our findings highlight that in adult mice subjected to a thermal injury, impaired wound healing is likely mediated by a disturbed cellular interplay between myeloid cells and mesenchymal cells.

miR-154 Influences HNSCC Development and Progression through Regulation of the Epithelial-to-Mesenchymal Transition Process and Could Be Used as a Potential Biomarker

MicroRNAs and their role in cancer have been extensively studied for the past decade. Here, we analyzed the biological role and diagnostic potential of miR-154-5p and miR-154-3p in head and neck squamous cell carcinoma (HNSCC). miRNA expression analyses were performed using The Cancer Genome Atlas (TCGA) data accessed from cBioPortal, UALCAN, Santa Cruz University, and Gene Expression Omnibus (GEO). The expression data were correlated with clinicopathological parameters. The functional enrichment was assessed with Gene Set Enrichment Analysis (GSEA). The immunological profiles were assessed using the ESTIMATE tool and RNAseq data from TCGA. All statistical analyses were performed with GraphPad Prism and Statistica. The study showed that both miR-154-5p and miR-154-3p were downregulated in the HNSCC samples and their expression levels correlated with tumor localization, overall survival, cancer stage, tumor grade, and HPV p16 status. GSEA indicated that individuals with the increased levels of miR-154 had upregulated AKT-MTOR, CYCLIN D1, KRAS, EIF4E, RB, ATM, and EMT gene sets. Finally, the elevated miR-154 expression correlated with better immune response. This study showed that miR-154 is highly involved in HNSCC pathogenesis, invasion, and immune response. The implementation of miR-154 as a biomarker may improve the effectiveness of HNSCC treatment.

Neural Functions Play Different Roles in Triple Negative Breast Cancer (TNBC) and non-TNBC

Triple negative breast cancer (TNBC) represents the most malignant subtype of breast cancer, and yet our understanding about its unique biology remains elusive. We have conducted a comparative computational analysis of transcriptomic data of TNBC and non-TNBC (NTNBC) tissue samples from the TCGA database, focused on genes involved in neural functions. Our main discoveries are: (1) while both subtypes involve neural functions, TNBC has substantially more up-regulated neural genes than NTNBC, suggesting that TNBC is more complex than NTNBC; (2) non-neural functions related to cell-microenvironment interactions and intracellular damage processing are key inducers of the neural genes in both TNBC and NTNBC, but the inducer-responder relationships are different in the two cancer subtypes; (3) key neural functions such as neural crest formation are predicted to enhance adaptive immunity in TNBC while glia development, along with a few other neural functions, induce both innate and adaptive immunity in NTNBC. These results reveal key differences in the biology between the two cancer subtypes, particularly in terms of the roles that neural functions play. Our findings may open new doors for further investigation of the distinct biology of TNBC vs. NTNBC.

Role of DNA methylation regulation of miR-130b expression in human lung cancer using bioinformatics analysis

MicroRNAs (miRNAs) are involved in various crucial biological processes including regulation of cell differentiation, proliferation, and migration, and are closely associated with tumor development. This study aimed to investigate miR-130b expression levels in lung cancer patient tissues. Two Gene Expression Omnibus (GEO) databases, including GSE48414 and GSE74190, and two The Cancer Genome Atlas (TCGA) databases including TCGA LUAD and TCGA LUSC, were accessed to obtain information for differential expression analysis and clinical-pathological correlation analysis. The results showed that miR-130b expression levels were significantly increased in lung cancer compared to normal tissues. Data also demonstrated that confounding factors such as tumor clinical stages and tumor invasion depth markedly affected miR-130b expression levels in cancer patients. A total of 169 target genes modified by miR-130b expression were identified by using 4 online websites for target gene prediction. Further enrichment analysis indicated that these 169 target genes were significantly enriched in several cancer-related biological processes and signaling pathways, including wound healing, cell proliferation, Wnt signaling, Ras signaling, and mTOR signaling. It was also of interest to examine the seven sites on the promoter region of miR-130b encoding gene in lung cancer patients and then compare methylation at these loci with miR-130b expression. The correlation analysis between encoding gene methylation and miR-130b expression in TCGA datasets revealed that decreased methylation in the promoter region was significantly associated with elevated miR-130b expression. This phenomenon was markedly dependent upon smoking history and clinical-pathological features. In conclusion, data indicated alterations in the methylation of DNA promoter region of miR-130b encoding gene were associated with disturbances in miR-130b expression in lung cancer patients suggesting that the DNA methylation process and miR-130b expression may serve as biomarkers for detection of lung cancer.

Cancer: the dark side of wound healing

Complex multicellular organisms have evolved sophisticated mechanisms to rapidly resolve epithelial injuries. Epithelial integrity is critical to maintaining internal homeostasis. An epithelial breach represents the potential for pathogen ingress and fluid loss, both of which may have severe consequences if not limited. The mammalian wound healing response involves a finely tuned, self-limiting series of cellular and molecular events orchestrated by the transient activation of specific signalling pathways. Accurate regulation of these events is essential; failure to initiate key steps at the right time delays healing and leads to chronic wounds, while aberrant initiation of wound healing processes may produce cell behaviours that promote cancer progression. In this review, we discuss how wound healing pathways co-opted in cancer lose their stringent regulation and become compromised in their reversibility. We hypothesize on how the commandeering of wound healing 'master regulators' is involved in this process, and also highlight the implications of these findings in the treatment of both chronic wounds and cancer.