Involvement of collagen XVII in pluripotency gene expression and metabolic reprogramming of lung cancer stem cells

LAMC2 regulates the proliferation, invasion, and metastasis of gastric cancer via PI3K/Akt signaling pathway

OBJECTIVES

Gastric cancer (GC) is a prevalent malignant tumor widely distributed globally, exhibiting elevated incidence and fatality rates. The gene LAMC2 encodes the laminin subunit gamma-2 chain and is found specifically in the basement membrane of epithelial cells. Its expression is aberrant in multiple types of malignant tumors. This research elucidated a link between LAMC2 and the clinical characteristics of GC and investigated the potential involvement of LAMC2 in GC proliferation and advancement.

MATERIALS AND METHODS

LAMC2 expressions were detected in GC cell lines and normal gastric epithelial cell lines via qRT-PCR. Silencing and overexpression of the LAMC2 were conducted by lentiviral transfection. A xenograft mouse model was also developed for in vivo analysis. Cell functional assays were conducted to elucidate the involvement of LAMC2 in cell growth, migration, and penetration. Further, immunoblotting was conducted to investigate the impact of LAMC2 on the activation of signal pathways after lentiviral transfection.

RESULTS

In the findings, LAMC2 expression was markedly upregulated in GC cell lines as opposed to normal gastric epithelial cells. In vitro analysis showed that sh-LAMC2 substantially inhibited GC cell growth, migration, and invasion, while oe-LAMC2 displayed a contrasting effect. Xenograft tumor models demonstrated that oe-LAMC2 accelerated tumor growth via high expression of Ki-67. Immunoblotting analysis revealed a substantial decrease in various signaling pathway proteins, PI3K, p-Akt, and Vimentin levels upon LAMC2 knockdown, followed by increased E-cadherin expression. Conversely, its overexpression exhibited contrasting effects. Besides, epithelial-mesenchymal transition (EMT) was accelerated by LAMC2.

CONCLUSION

This study provides evidence indicating that LAMC2, by stimulating signaling pathways, facilitated EMT and stimulated the progression of GC cells in laboratory settings and mouse models. Research also explored that the abnormal LAMC2 expression acts as a biomarker for GC.

Identification of molecular subtypes and diagnostic model in clear cell renal cell carcinoma based on collagen-related genes may predict the response of immunotherapy

Background: Collagen represents a prominent constituent of the tumor's extracellular matrix (ECM). Nonetheless, its correlation with the molecular subtype attributes of clear cell renal cell carcinoma (ccRCC) remains elusive. Our objective is to delineate collagen-associated molecular subtypes and further construct diagnostic model, offering insights conducive to the precise selection of ccRCC patients for immunotherapeutic interventions. Methods: We performed unsupervised non-negative matrix factorization (NMF) analysis on TCGA-KIRC samples, utilizing a set of 33 collagen-related differentially expressed genes (33CRDs) for clustering. Our analysis encompassed evaluations of subtype-associated differences in pathways, immune profiles, and somatic mutations. Through weighted gene co-expression network analysis (WGCNA) and four machine learning algorithms, two core genes were found and a diagnostic model was constructed. This was subsequently validated in a clinical immunotherapy cohort. Single cell sequencing analysis and experiments demonstrated the role of core genes in ccRCC. Finally, we also analyzed the roles of MMP9 and SCGN in pan-cancer. Results: We described two novel collagen related molecular subtypes in ccRCC, designated subtype 1 and subtype 2. Compared with subtype 1, subtype 2 showed more infiltration of immune components, but had a higher TIDE (tumor immunedysfunctionandexclusion) score and increased levels of immune checkpoint molecules. Furthermore, reduced prognosis for subtype 2 was a consistent finding in both high and low mutation load subgroups. MMP9 and SCGN were identified as key genes for distinguishing subtype 1 and subtype 2. The diagnostic model based on them could better distinguish the subtype of patients, and the differentiated patients had different progression free survival (PFS) in the clinical immunotherapy cohort. MMP9 was predominantly expressed in macrophages and has been extensively documented in the literature. Meanwhile, SCGN, which was overexpressed in tumor cells, underwent experimental validation, emphasizing its role in ccRCC. In various cancers, MMP9 and SCGN were associated with immune-related molecules and immune cells. Conclusion: Our study identifies two collagen-related molecular subtypes of ccRCC and constructs a diagnostic model to help select appropriate patients for immunotherapy.

Nanomedicine Strategies for Targeting Tumor Stroma

The tumor stroma, or the microenvironment surrounding solid tumors, can significantly impact the effectiveness of cancer therapies. The tumor microenvironment is characterized by high interstitial pressure, a consequence of leaky vasculature, and dense stroma created by excessive deposition of various macromolecules such as collagen, fibronectin, and hyaluronic acid (HA). In addition, non-cancerous cells such as cancer-associated fibroblasts (CAFs) and the extracellular matrix (ECM) itself can promote tumor growth. In recent years, there has been increased interest in combining standard cancer treatments with stromal-targeting strategies or stromal modulators to improve therapeutic outcomes. Furthermore, the use of nanomedicine, which can improve the delivery and retention of drugs in the tumor, has been proposed to target the stroma. This review focuses on how different stromal components contribute to tumor progression and impede chemotherapeutic delivery. Additionally, this review highlights recent advancements in nanomedicine-based stromal modulation and discusses potential future directions for developing more effective stroma-targeted cancer therapies.

Cancer stem cells: Recent insights and therapies

Tumors are intricate ecosystems containing malignant components that generate adaptive and evolutionarily driven abnormal tissues. Through self-renewal and differentiation, cancers are reconstructed by a dynamic subset of stem-like cells that enforce tumor heterogeneity and remodel the tumor microenvironment (TME). Through recent technology advances, we are now better equipped to investigate the fundamental role of cancer stem cells (CSCs) in cancer biology. In this review, we discuss the latest insights into characteristics, markers and mechanism of CSCs and describe the crosstalk between CSCs and other cells in TME. Additionally, we explore the performance of single-cell sequencing and spatial transcriptome analysis in CSCs studies and summarize the therapeutic strategies to eliminate CSCs, which could broaden the understanding of CSCs and exploit for therapeutic benefit.

Collagen Family as Promising Biomarkers and Therapeutic Targets in Cancer

Despite advances in cancer detection and therapy, it has been estimated that the incidence of cancers will increase, while the mortality rate will continue to remain high, a fact explained by the large number of patients diagnosed in advanced stages when therapy is often useless. Therefore, it is necessary to invest knowledge and resources in the development of new non-invasive biomarkers for the early detection of cancer and new therapeutic targets for better health management. In this review, we provided an overview on the collagen family as promising biomarkers and on how they may be exploited as therapeutic targets in cancer. The collagen family tridimensional structure, organization, and functions are very complex, being in a tight relationship with the extracellular matrix, tumor, and immune microenvironment. Moreover, accumulating evidence underlines the role of collagens in promoting tumor growth and creating a permissive tumor microenvironment for metastatic dissemination. Knowledge of the molecular basis of these interactions may help in cancer diagnosis and prognosis, in overcoming chemoresistance, and in providing new targets for cancer therapies.

Snail induces dormancy in disseminated luminal type A breast cancer through Src inhibition

Breast cancer includes biologically distinct subtypes, and the time between rise in distant metastases and overall survival for the subtypes are different. The mechanisms involved in these differences in tumor metastasis remain to be elucidated. Here, we demonstrated that, luminal type A breast cancer cells, such as MCF7 and T47D, when overexpressed with active mutant form of Snail (6SA-Snail) increased in the expression of EMT markers such as Vimentin, N-cadherin and Fibronectin but decreased in the expression of E-cadherin, compared to control vectors or wild type Snail. Moreover, this mutant increased in migration and invasion ability, while decreased in the capacity to survive and form spheres in tumor spheroid medium. Luciferase reporter assay and chromatin immunoprecipitation followed by quantitative PCR (ChIP-qPCR) analysis revealed that Snail downregulated Src by binding to the E-box of Src promoter. Human luminal type A breast cancer specimens showed an inverse correlation between Vimentin and Src expression. Most importantly, downregulation of Src by Snail was not found in breast cancer cell types other than luminal type A. Therefore, elucidation of the differences in signaling pathways involved in controlling migration, invasion and colonization may have a therapeutically beneficial effect on breast cancer treatment.

Immune- and Stemness-Related Genes Revealed by Comprehensive Analysis and Validation for Cancer Immunity and Prognosis and Its Nomogram in Lung Adenocarcinoma

Objective

Lung adenocarcinoma (LUAD) is a familiar lung cancer with a very poor prognosis. This study investigated the immune- and stemness-related genes to develop model related with cancer immunity and prognosis in LUAD.

Method

The Cancer Genome Atlas (TCGA) was utilized for obtaining original transcriptome data and clinical information. Differential expression, prognostic value, and correlation with clinic parameter of mRNA stemness index (mRNAsi) were conducted in LUAD. Significant mRNAsi-related module and hub genes were screened using weighted gene coexpression network analysis (WGCNA). Meanwhile, immune-related differential genes (IRGs) were screened in LUAD. Stem cell index and immune-related differential genes (SC-IRGs) were screened and further developed to construct prognosis-related model and nomogram. Comprehensive analysis of hub genes and subgroups, involving enrichment in the subgroup [gene set enrichment analysis (GSEA)], gene mutation, genetic correlation, gene expression, immune, tumor mutation burden (TMB), and drug sensitivity, used bioinformatics and reverse transcription polymerase chain reaction (RT-PCR) for verification.

Results

Through difference analysis, mRNAsi of LUAD group was markedly higher than that of normal group. Clinical parameters (age, gender, and T staging) were ascertained to be highly relevant to mRNAsi. MEturquoise and MEblue were found to be the most significant modules (including positive and negative correlations) related to mRNAsi via WGCNA. The functions and pathways of the two mRNAsi-related modules were mainly enriched in tumorigenesis, development, and metastasis. Combining stem cell index–related differential genes and immune-related differential genes, 30 prognosis-related SC-IRGs were screened via Cox regression analysis. Then, 16 prognosis-related SC-IRGs were screened to construct a LASSO regression model at last. In addition, the model was successfully validated by using TCGA-LUAD and GSE68465, whereas c-index and the calibration curves were utilized to demonstrate the clinical value of our nomogram. Following the validation of the model, GSEA, immune cell correlation, TMB, clinical relevance, etc., have found significant difference in high- and low-risk groups, and 16-gene expression of the SC-IRG model also was tested by RT-PCR. ADRB2, ANGPTL4, BDNF, CBLC, CX3CR1, and IL3RA were found markedly different expression between the tumor and normal group.

Conclusion

The SC-IRG model and the prognostic nomogram could accurately predict LUAD survival. Our study used mRNAsi combined with immunity that may lay a foundation for the future research studies in LUAD.

Noncoding RNAs in triple negative breast cancer: Mechanisms for chemoresistance

Triple-negative breast cancer (TNBC) is the most aggressive subtype among breast cancers with high recurrence and this condition is partly due to chemoresistance. Therefore, fully understanding the mechanism of TNBC-resistance is the key to overcoming chemoresistance, which will be an effective strategy for TNBC therapy. Various potential mechanisms involved in the chemoresistance of TNBC have been investigated and indicated that noncoding RNAs (ncRNAs) especially microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) take part in most TNBC resistance. The ncRNA-induced chemoresistance process is involved in the alteration of many activities. here, we mainly summarize the mechanisms of ncRNAs in the chemoresistance of TNBC and discuss the potential clinical application of ncRNAs in the treatment of TNBC, indicating that targeting ncRNAs might be a promising strategy for resensitization to chemotherapies.

BP180/Collagen XVII: A Molecular View

BP180 is a type II collagenous transmembrane protein and is best known as the major autoantigen in the blistering skin disease bullous pemphigoid (BP). The BP180 trimer is a central component in type I hemidesmosomes (HD), which cause the adhesion between epidermal keratinocytes and the basal lamina, but BP180 is also expressed in several non-HD locations, where its functions are poorly characterized. The immunological roles of intact and proteolytically processed BP180, relevant in BP, have been subject to intensive research, but novel functions in cell proliferation, differentiation, and aging have also recently been described. To better understand the multiple physiological functions of BP180, the focus should return to the protein itself. Here, we comprehensively review the properties of the BP180 molecule, present new data on the biochemical features of its intracellular domain, and discuss their significance with regard to BP180 folding and protein-protein interactions.

Metabolic Targeting of Cancer Stem Cells

Most human tumors possess a high heterogeneity resulting from both clonal evolution and cell differentiation program. The process of cell differentiation is initiated from a population of cancer stem cells (CSCs), which are enriched in tumor-regenerating and tumor-propagating activities and responsible for tumor maintenance and regrowth after treatment. Intrinsic resistance to conventional therapies, as well as a high degree of phenotypic plasticity, makes CSCs hard-to-target tumor cell population. Reprogramming of CSC metabolic pathways plays an essential role in tumor progression and metastatic spread. Many of these pathways confer cell adaptation to the microenvironmental stresses, including a shortage of nutrients and anti-cancer therapies. A better understanding of CSC metabolic dependences as well as metabolic communication between CSCs and the tumor microenvironment are of utmost importance for efficient cancer treatment. In this mini-review, we discuss the general characteristics of CSC metabolism and potential metabolic targeting of CSC populations as a potent strategy to enhance the efficacy of conventional treatment approaches.

Tobacco Smoke Plays an Important Role in Initiation and Development of Lung Cancer by Promoting the Characteristics of Cancer Stem Cells

Lung cancer is one of the most common causes of cancer-related deaths worldwide. Tobacco smoke is the single greatest risk factor of lung cancer. Although enormous progress in understanding the molecular mechanisms by which tobacco smoke leading to lung cancer has been made, the molecular pathogenesis remains largely unclear. Cancer stem cells have been implicated in cancer initiation, development, and drug resistance. In this review, we reviewed the relationship between tobacco smoke and lung cancer, the key role of cancer stem cells in lung cancer and other tumors. More importantly, we elucidate the mechanism of tobacco smoke promoting lung cancer from the perspective of the characteristics of cancer stem cells induced by tobacco smoke.

Versatile role of curcumin and its derivatives in lung cancer therapy

Lung cancer is a main cause of death all over the world with a high incidence rate. Metastasis into neighboring and distant tissues as well as resistance of cancer cells to chemotherapy demand novel strategies in lung cancer therapy. Curcumin is a naturally occurring nutraceutical compound derived from Curcuma longa (turmeric) that has great pharmacological effects, such as anti-inflammatory, neuroprotective, and antidiabetic. The excellent antitumor activity of curcumin has led to its extensive application in the treatment of various cancers. In the present review, we describe the antitumor activity of curcumin against lung cancer. Curcumin affects different molecular pathways such as vascular endothelial growth factors, nuclear factor-κB (NF-κB), mammalian target of rapamycin, PI3/Akt, microRNAs, and long noncoding RNAs in treatment of lung cancer. Curcumin also can induce autophagy, apoptosis, and cell cycle arrest to reduce the viability and proliferation of lung cancer cells. Notably, curcumin supplementation sensitizes cancer cells to chemotherapy and enhances chemotherapy-mediated apoptosis. Curcumin can elevate the efficacy of radiotherapy in lung cancer therapy by targeting various signaling pathways, such as epidermal growth factor receptor and NF-κB. Curcumin-loaded nanocarriers enhance the bioavailability, cellular uptake, and antitumor activity of curcumin. The aforementioned effects are comprehensively discussed in the current review to further direct studies for applying curcumin in lung cancer therapy.

The Role of Collagen XVII in Cancer: Squamous Cell Carcinoma and Beyond

Alterations in the extracellular matrix (ECM) likely facilitate the first steps of cancer cell metastasis and supports tumor progression. Recent data has demonstrated that alterations in collagen XVII (BP180), a transmembrane protein and structural component of the ECM, can have profound effects on cancer invasiveness. Collagen XVII is a homotrimer of three α1 (XVII) chains. Its intracellular domain contains binding sites for plectin, integrin β4, and BP230, while the extracellular domain facilitates interactions between the cell and the ECM. Collagen XVII and its shed ectodomain have been implicated in cell motility and adhesion and are believed to promote tumor development and invasion. A strong association of collagen XVII ectodomain shedding and tumor invasiveness occurs in squamous cell carcinoma (SCC). Aberrant expression of collagen XVII has been reported in many epithelial cancers, ranging from squamous cell carcinoma to colon, pancreatic, mammary, and ovarian carcinoma. Thus, in this review, we focus on collagen XVII's role in neoplasia and tumorigenesis. Lastly, we discuss the importance of targeting collagen XVII and its ectodomain shedding as a novel strategy to curb tumor growth and reduce metastatic potential.