3D matrix promotes cell dedifferentiation into colorectal cancer stem cells via integrin/cytoskeleton/glycolysis signaling

3D pancreatic ductal adenocarcinoma desmoplastic model: Glycolysis facilitating stemness via ITGAV-PI3K-AKT-YAP1

The distinctive desmoplastic tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) is crucial in determining the stemness of tumor cells. And the conventional two-dimensional (2D) culture does not adequately mimic the TME. Therefore, a three-dimensional (3D) PDAC desmoplastic model was constructed using GelMA and HAMA, which provides benefits in terms of simulating both the main components (COL and HA) and the crosslinking of the extracellular matrix. We found that the 3D PDAC desmoplastic model upregulated the expression of the markers for stemness (NANOG and OCT4) and glycolysis (HK2 and GLUT2), and elevated the level of glycolysis, including increased glucose consumption and lactic acid production. Additionally, YAP1 played a crucial role in promoting glycolysis, which boosted stemness. Furthermore, RNA sequencing (RNA-seq) was employed to explore the underlying mechanisms associated with stemness within the 3D desmoplastic model. Subsequent KEGG pathway analysis indicated the activation of the PI3K-AKT signaling pathway, providing insights into the molecular processes at play. Using bioinformatics, qRT-PCR and western blot, we proposed that ITGAV-PI3K-AKT-YAP1 axis may account for the glycolysis mediated the stemness. Collectively, the 3D desmoplastic model may serve as a new platform for understanding the underlying mechanism by which the TME induces stemness.

ITGA3 promotes pancreatic cancer progression through HIF1α- and c-Myc-driven glycolysis in a collagen I-dependent autocrine manner

Pancreatic cancer is characterized by severe metabolic stress due to its prominent desmoplasia and poor vascularization. Integrin subunit alpha 3 (ITGA3) is a cell surface adhesion protein involved in tumor progression. However, the role of ITGA3 in pancreatic cancer progression, especially in metabolic reprogramming, remains largely unknown. In this study, we found that ITGA3 expression is elevated in pancreatic cancer tissues and predicts poor prognosis for patients with pancreatic cancer. Functional assays revealed that ITGA3 promotes the growth and liver metastasis of pancreatic cancer via boosting glycolysis. Mechanistically, Collagen I (Col1) derived from cancer cells acts as a ligand for ITGA3 to activate the FAK/PI3K/AKT/mTOR signaling pathway in an autocrine manner, thereby increasing the expression of HIF1α and c-Myc, two critical regulators of glycolysis. Blockade of Col1 by siRNA or of ITGA3 by a blocking antibody leads to specific inactivation of the FAK/PI3K/AKT/mTOR pathway and impairs malignant tumor behaviors induced by ITGA3. Thus, our data indicate that ITGA3 enhances glycolysis to promote pancreatic cancer growth and metastasis via increasing HIF1α and c-Myc expression in a Col1-dependent autocrine manner, making ITGA3 as a candidate diagnostic biomarker and a potential therapeutic target for pancreatic cancer.

Thermo-Responsive Hydrogel Based on Lung Decellularized Extracellular Matrix for 3D Culture Model to Enhance Cancer Stem Cell Characteristics

Cancer stem cells (CSCs) are most likely the main cause of lung cancer formation, metastasis, drug resistance, and genetic heterogeneity. Three-dimensional (3D) ex vivo cell culture models can facilitate stemness improvement and CSC enrichment. Considering the critical role of extracellular matrix (ECM) on CSC properties, the present study developed a thermo-responsive hydrogel using the porcine decellularized lung for 3D cell culture, and the cell-laden hydrogel culturing model was used to explore the CSC characteristics and potential utilization in CSC-specific drug evaluation. Results showed that the lung dECM hydrogel (LEH) was composed of the main ECM components and displayed excellent cellular compatibility. In addition, lung cancer cells 3D cultured in LEH displayed the overexpression of metastasis-related genes and enhanced migration properties, as compared with those in two-dimensional (2D) conditions. Notably, the CSC features, including the expression level of stemness-associated genes, colony formation capability, drug resistance, and the proportion of cancer stem-like cells (CD133+), were also enhanced in 3D cells. Furthermore, the attenuation effect of epigallocatechin gallate (EGCG) on CSC properties in the 3D model was observed, confirming the potential practicability of the 3D culture on CSC-targeted drug screening. Overall, our results suggest that the fabricated LEH is an effective and facile platform for 3D cell culture and CSC-specific drug evaluation.

Integrins in cancer stem cells

Integrins are a class of adhesion receptors on cell membranes, consisting of α and β subunits. By binding to the extracellular matrix, integrins activate intracellular signaling pathways, participating in every step of cancer initiation and progression. Tumor stem cells possess self-renewal and self-differentiation abilities, along with strong tumorigenic potential. In this review, we discussed the role of integrins in cancer, with a focus on their impact on tumor stem cells and tumor stemness. This will aid in targeting tumor stem cells as a therapeutic approach, leading to the exploration of novel cancer treatment strategies.

Integrinβ-1 in disorders and cancers: molecular mechanisms and therapeutic targets

Integrinβ-1 (ITGB1) is a crucial member of the transmembrane glycoprotein signaling receptor family and is also central to the integrin family. It forms heterodimers with other ligands, participates in intracellular signaling and controls a variety of cellular processes, such as angiogenesis and the growth of neurons; because of its role in bidirectional signaling regulation both inside and outside the membrane, ITGB1 must interact with a multitude of substances, so a variety of interfering factors can affect ITGB1 and lead to changes in its function. Over the past 20 years, many studies have confirmed a clear causal relationship between ITGB1 dysregulation and cancer development and progression in a wide range of benign diseases and solid tumor types, which may imply that ITGB1 is a prognostic biomarker and a therapeutic target for cancer treatment that warrants further investigation. This review summarizes the biological roles of ITGB1 in benign diseases and cancers, and compiles the current status of ITGB1 function and therapy in various aspects of tumorigenesis and progression. Finally, future research directions and application prospects of ITGB1 are suggested. Video Abstract.

Integrins in cancer: Emerging mechanisms and therapeutic opportunities

Integrins are vital surface adhesion receptors that mediate the interactions between the extracellular matrix (ECM) and cells and are essential for cell migration and the maintenance of tissue homeostasis. Aberrant integrin activation promotes initial tumor formation, growth, and metastasis. Recently, many lines of evidence have indicated that integrins are highly expressed in numerous cancer types and have documented many functions of integrins in tumorigenesis. Thus, integrins have emerged as attractive targets for the development of cancer therapeutics. In this review, we discuss the underlying molecular mechanisms by which integrins contribute to most of the hallmarks of cancer. We focus on recent progress on integrin regulators, binding proteins, and downstream effectors. We highlight the role of integrins in the regulation of tumor metastasis, immune evasion, metabolic reprogramming, and other hallmarks of cancer. In addition, integrin-targeted immunotherapy and other integrin inhibitors that have been used in preclinical and clinical studies are summarized.

A Brief Review on Chemoresistance; Targeting Cancer Stem Cells as an Alternative Approach

The acquisition of resistance to traditional chemotherapy and the chemoresistant metastatic relapse of minimal residual disease both play a key role in the treatment failure and poor prognosis of cancer. Understanding how cancer cells overcome chemotherapy-induced cell death is critical to improve patient survival rate. Here, we briefly describe the technical approach directed at obtaining chemoresistant cell lines and we will focus on the main defense mechanisms against common chemotherapy triggers by tumor cells. Such as, the alteration of drug influx/efflux, the enhancement of drug metabolic neutralization, the improvement of DNA-repair mechanisms, the inhibition of apoptosis-related cell death, and the role of p53 and reactive oxygen species (ROS) levels in chemoresistance. Furthermore, we will focus on cancer stem cells (CSCs), the cell population that subsists after chemotherapy, increasing drug resistance by different processes such as epithelial-mesenchymal transition (EMT), an enhanced DNA repair machinery, and the capacity to avoid apoptosis mediated by BCL2 family proteins, such as BCL-XL, and the flexibility of their metabolism. Finally, we will review the latest approaches aimed at decreasing CSCs. Nevertheless, the development of long-term therapies to manage and control CSCs populations within the tumors is still necessary.