Formin-like 2 promotes angiogenesis and metastasis of colorectal cancer by regulating the EGFL6/CKAP4/ERK axis

Analysis of extracellular vesicles of frequently used colorectal cancer cell lines

Colorectal cancer (CRC) ranks as the second most prevalent malignancy globally, highlighting the urgent need for more effective diagnostic and therapeutic strategies, as well as a deeper understanding of its molecular basis. Extensive research has demonstrated that cells actively secrete extracellular vesicles (EVs) to mediate intercellular communication at both proximal and distal sites. In this study, we conducted a comprehensive analysis of the RNA content of small extracellular vesicles (sEVs) secreted into the culture media of five frequently utilised CRC cell lines (RKO, HCT116, HCT15, HT29, and DLD1). RNA sequencing data revealed significant insights into the RNA profiles of these sEVs, identifying nine protein-coding genes and fourteen long non-coding RNA (lncRNA) genes that consistently ranked among the top 30 most abundant across all cell lines. Notably, the genes found in sEVs were highly similar among the cell lines, indicating a conserved molecular signature. Several of these genes have been previously documented in the context of cancer biology, while others represent novel discoveries. These findings provide valuable insights into the molecular cargo of sEVs in CRC, potentially unveiling novel biomarkers and therapeutic targets.

Emerging roles of EGFL family members in neoplastic diseases: Molecular mechanisms and targeted therapies

Epidermal growth factor-like proteins (EGFLs) contain more than a single EGF/EGF-like domain within their protein structure. To date, ten EGFL family members (EGFL1-10) have been characterized across diverse tissues and developmental stages under different conditions. In this review, we conclude that EGFLs are instrumental in regulating biological activities and pathological processes. Under physiological conditions, EGFLs participate in angiogenesis, neurogenesis, osteogenesis, and other processes. Under pathological conditions, EGFLs are linked with different diseases, particularly cancers. Furthermore, we highlight recent advancements in the study of EGFLs in biological conditions and cancers. In addition, the regulatory role and key underlying mechanism of EGFLs in mediating tumorigenesis are discussed. This paper also examines potential antagonists that target EGFL family members in cancer therapeutics. In summary, this comprehensive review elucidates the critical role of EGFLs in neoplastic diseases and highlights their potential as therapeutic targets.

Exosomal signaling in cancer metastasis: Molecular insights and therapeutic opportunities

Exosomes are membrane-bound extracellular vesicles that play a role in exchanging biological products across membranes and serve as intermediaries in intercellular communication to maintain normal homeostasis. Numerous molecules, including lipids, proteins, and nucleic acids are enclosed in exosomes. Exosomes are constantly released into the extracellular environment and exhibit distinct characteristics based on the secreted cells that produce them. Exosome-mediated cell-to-cell communication has reportedly been shown to affect multiple cancer hallmarks, such as immune response modulation, pre-metastatic niche formation, angiogenesis, stromal cell reprogramming, extracellular matrix architecture remodeling, or even drug resistance, and eventually the development and metastasis of cancer cells. Exosomes can be used as therapeutic targets and possible diagnostic biomarkers by selectively loading oncogenic molecules into them. We highlight the important roles that exosomes play in cancer development in this review, which may lead to the development of fresh approaches for future clinical uses.

Formin-like 1β phosphorylation at S1086 is necessary for secretory polarized traffic of exosomes at the immune synapse in Jurkat T lymphocytes

We analyzed here how formin-like 1 β (FMNL1β), an actin cytoskeleton-regulatory protein, regulates microtubule-organizing center (MTOC) and multivesicular bodies (MVB) polarization and exosome secretion at an immune synapse (IS) model in a phosphorylation-dependent manner. IS formation was associated with transient recruitment of FMNL1β to the IS, which was independent of protein kinase C δ (PKCδ). Simultaneous RNA interference of all FMNL1 isoforms prevented MTOC/MVB polarization and exosome secretion, which were restored by FMNL1βWT expression. However, expression of the non-phosphorylatable mutant FMNL1βS1086A did not restore neither MTOC/MVB polarization nor exosome secretion to control levels, supporting the crucial role of S1086 phosphorylation in MTOC/MVB polarization and exosome secretion. In contrast, the phosphomimetic mutant, FMNL1βS1086D, restored MTOC/MVB polarization and exosome secretion. Conversely, FMNL1βS1086D mutant did not recover the deficient MTOC/MVB polarization occurring in PKCδ-interfered clones, indicating that S1086 FMNL1β phosphorylation alone is not sufficient for MTOC/MVB polarization and exosome secretion. FMNL1 interference inhibited the depletion of F-actin at the central region of the immune synapse (cIS), which is necessary for MTOC/MVB polarization. FMNL1βWT and FMNL1βS1086D, but not FMNL1βS1086A expression, restored F-actin depletion at the cIS. Thus, actin cytoskeleton reorganization at the IS underlies the effects of all these FMNL1β variants on polarized secretory traffic. FMNL1 was found in the IS made by primary T lymphocytes, both in T cell receptor (TCR) and chimeric antigen receptor (CAR)-evoked synapses. Taken together, these results point out a crucial role of S1086 phosphorylation in FMNL1β activation, leading to cortical actin reorganization and subsequent control of MTOC/MVB polarization and exosome secretion.

The role of PIK3CA gene mutations in colorectal cancer and the selection of treatment strategies

PIK3CA gene encodes the p110α catalytic subunit of PI3K, which regulates the PI3K/AKT/mTOR signaling pathway. PIK3CA gene mutation is one of the most common mutations in colorectal cancer (CRC), affecting about 15%-20% of CRC patients. PIK3CA gene mutation leads to the persistent activation of the PI3K/AKT/mTOR signaling pathway, which promotes the proliferation, invasion, metastasis, and drug resistance of CRC. This article provides a summary of the key detection methods for PIK3CA gene mutation, and provides an introduction to the existing colorectal cancer treatments and their practical applications in the clinic. Besides, this article summarizes the role and mechanism of PIK3CA gene mutation in the occurrence and development of CRC. It also explores the relationship between PIK3CA gene mutation and the clinical features and prognosis of CRC. This article focuses on the influence and mechanism of PIK3CA gene mutation on the targeted therapy and immunotherapy of CRC, and discusses the potential value and future direction of PIK3CA gene mutation in the personalized therapy of CRC. We aim to provide new perspectives and ideas for the precise diagnosis and treatment of CRC.

Infliximab modifies CD74-mediated lymphatic abnormalities and adipose tissue alterations in creeping fat of Crohn's disease

BACKGROUND

Lymphatic abnormalities are essential for pathophysiologic changes of creeping fat (CrF) in Crohn's disease (CD). Anti-tumor necrosis factor (TNF) therapy has been proved to alleviate CrF lesions, however, whether it achieves these by remodeling lymphatics is unknown.

METHODS

CD74 expression was detected in CrF and uninvolved mesentery of CD patients. Lymphatic functions in vitro were evaluated and lymphatic endothelium barrier were checked by transendothelial electrical resistance (TEER) and FITC-Dextran permeability. Protein level of tight junction and signaling pathways were detected by western blotting.

RESULTS

CD74 was upregulated in LECs of CrF and positively correlated with TNF-α synthesis. This was suppressed by IFX administration. In vitro, TNF-α stimulated LECs to express CD74 through NF-κB signaling pathway, and this was rescued by IFX. CD74 downregulation suppressed the abilities of LECs in proliferation, migration and tube formation. Interaction of CD74-MIF impaired LECs' barrier via reducing tight junction proteins in an ERK1/2-dependent manner, which was reversed by CD74 downregulation. Consistently, the CD patients receiving IFX therapy displayed decreased lymphangiogenesis and improved mesenteric lymphatic endothelium barrier, companied with reduced adipocyte size and adipokine levels in CrF.

CONCLUSIONS

Anti-TNF therapy could modify pathological changes in CrF by alleviating CD74-mediated lymphatic abnormalities.

Identification of an FMNL2 Interactome by Quantitative Mass Spectrometry

Formin Homology Proteins (Formins) are a highly conserved family of cytoskeletal regulatory proteins that participate in a diverse range of cellular processes. FMNL2 is a member of the Diaphanous-Related Formin sub-group, and previous reports suggest FMNL2's role in filopodia assembly, force generation at lamellipodia, subcellular trafficking, cell-cell junction assembly, and focal adhesion formation. How FMNL2 is recruited to these sites of action is not well understood. To shed light on how FMNL2 activity is partitioned between subcellular locations, we used biotin proximity labeling and proteomic analysis to identify an FMNL2 interactome. The interactome identified known and new FMNL2 interacting proteins with functions related to previously described FMNL2 activities. In addition, our interactome predicts a novel connection between FMNL2 and extracellular vesicle assembly. We show directly that FMNL2 protein is present in exosomes.

Cancer-derived exosomes as novel biomarkers in metastatic gastrointestinal cancer

Gastrointestinal cancer (GIC) is the most prevalent and highly metastatic malignant tumor and has a significant impact on mortality rates. Nevertheless, the swift advancement of contemporary technology has not seamlessly aligned with the evolution of detection methodologies, resulting in a deficit of innovative and efficient clinical assays for GIC. Given that exosomes are preferentially released by a myriad of cellular entities, predominantly originating from neoplastic cells, this confers exosomes with a composition enriched in cancer-specific constituents. Furthermore, exosomes exhibit ubiquitous presence across diverse biological fluids, endowing them with the inherent advantages of non-invasiveness, real-time monitoring, and tumor specificity. The unparalleled advantages inherent in exosomes render them as an ideal liquid biopsy biomarker for early diagnosis, prognosticating the potential development of GIC metastasis.In this review, we summarized the latest research progress and possible potential targets on cancer-derived exosomes (CDEs) in GIC with an emphasis on the mechanisms of exosome promoting cancer metastasis, highlighting the potential roles of CDEs as the biomarker and treatment in metastatic GIC.