Immune-related cell death index and its application for hepatocellular carcinoma

Regulated cell death (RCD) plays a crucial role in the immune microenvironment, development, and progression of hepatocellular carcinoma (HCC). However, reliable immune-related cell death signatures have not been explored. In this study, we collected 12 RCD modes (e.g., apoptosis, ferroptosis, and cuproptosis), including 1078 regulators, to identify immune-related cell death genes based on HCC immune subgroups. Using a developed competitive machine learning framework, nine genes were screened to construct the immune-related cell death index (IRCDI), which is available for online application. Multi-omics data, along with clinical features, were analyzed to explore the HCC malignant heterogeneity. To validate the efficacy of this model, more than 18 independent cohorts, including survival and diverse treatment cohorts and datasets, were utilized. These findings were further validated using in-house samples and molecular biological experiments. Overall, the IRCDI may have a wide application in individual therapeutic decision-making and improving outcomes for HCC patients.

L1CAM mediates neuroendocrine phenotype acquisition in prostate cancer cells

BACKGROUND

A specific type of prostate cancer (PC) that exhibits neuroendocrine (NE) differentiation is known as NEPC. NEPC has little to no response to androgen deprivation therapy and is associated with the development of metastatic castration-resistant PC (CRPC), which has an extremely poor prognosis. Our understanding of genetic drivers and activated pathways in NEPC is limited, which hinders precision medicine approaches. L1 cell adhesion molecule (L1CAM) is known to play an oncogenic role in metastatic cancers, including CRPC. However, the impact of L1CAM on NEPC progression remains elusive.

METHODS

L1CAM expression level was investigated using public gene expression databases of PC cohorts and patient-derived xenograft models. L1CAM knockdown was performed in different PC cells to study in vitro cell functions. A subline of CRPC cell line CWR22Rv1 was established after long-term exposure to abiraterone to induce NE differentiation. The androgen receptor-negative cell line PC3 was cultured under the tumor sphere-forming condition to enrich cancer stemness features. Several oxidative stress inducers were tested on PC cells to observe L1CAM-mediated gene expression and cell death.

RESULTS

L1CAM expression was remarkably high in NEPC compared to CRPC or adenocarcinoma tumors. L1CAM was also correlated with NE marker expressions and associated with the adenocarcinoma-to-NEPC progression in gene expression databases and CRPC cells with NE differentiation. L1CAM also promoted cancer stemness and NE phenotypes in PC3 cells under cancer stemness enrichment. L1CAM was also identified as a reactive oxygen species-induced gene, by which L1CAM counteracted CRPC cell death triggered by ionizing radiation.

CONCLUSIONS

Our results unveiled a new role of L1CAM in the acquisition of the NE phenotype in PC, contributing to the NE differentiation-related therapeutic resistance of CRPC.

Expression of L1 Cell Adhesion Molecule, a Nephronal Principal Cell Marker, in Nephrogenic Adenoma

Nephrogenic adenoma (NA) is a benign, reactive lesion seen predominantly in the urinary bladder and often associated with antecedent inflammation, instrumentation, or an operative history. Its histopathologic diversity can create diagnostic dilemmas and pathologists use morphologic evaluation along with available immunohistochemical (IHC) markers to navigate these challenges. IHC assays currently do not designate or specify NA's potential putative cell of origin. Leveraging single-cell RNA-sequencing technology, we nominated a principal (P) cell-collecting duct marker, L1 cell adhesion molecule (L1CAM), as a potential biomarker for NA. IHC characterization revealed L1CAM to be positive in all 35 (100%) patient samples of NA; negative expression was seen in the benign urothelium, benign prostatic glands, urothelial carcinoma (UCA) in situ, prostatic adenocarcinoma, majority of high-grade UCA, and metastatic UCA. In the study, we also used single-cell RNA sequencing to nominate a novel compendium of biomarkers specific for the proximal tubule, loop of Henle, and distal tubule (DT) (including P and intercalated cells), which can be used to perform nephronal mapping using RNA in situ hybridization and IHC technology. Employing this technique on NA we found enrichment of both the P-cell marker L1CAM and, the proximal tubule type-A and -B cell markers, PDZKI1P1 and PIGR, respectively. The cell-type markers for the intercalated cell of DTs (LINC01187 and FOXI1), and the loop of Henle (UMOD and IRX5), were found to be uniformly absent in NA. Overall, our findings show that based on cell type-specific implications of L1CAM expression, the shared expression pattern of L1CAM between DT P cells and NA. L1CAM expression will be of potential value in assisting surgical pathologists toward a diagnosis of NA in challenging patient samples.

State of the art and perspectives of chimeric antigen receptor T cells cell therapy for neuroblastoma

Neuroblastoma (NB) is a solid, neuroendocrine pediatric solid tumor with divergent clinical behavior. Patients with high-risk diseases have poor prognoses despite complex multimodal therapy, which requires the search for new therapeutic approaches. Chimeric antigen receptor T cells (CAR-T) have led to dramatic improvements in the survival of cancer patients, most notably those with hematologic malignancies. Early-phase clinical trials of CAR-T cell therapy for NB have proven safe and feasible, but limited clinical efficacy. At the same time, multiple experimental and preclinical studies have shown that the most common in clinical trials single 2nd or 3rd generation CAR structure is not sufficient for a complete response in solid tumors. Here, we review the recent advances and future perspectives associated with engineered receptors, including several antigens binding, armored CAR-T of 4th and 5th generation and CAR-T cell combination strategies with other immunotherapy. We also summarize the results and shortcomings of ongoing clinical trials of CAR-T therapy for NB.

L1 Cell Adhesion Molecule (L1CAM) Expression and Molecular Alterations Distinguish Low-Grade Oncocytic Tumor From Eosinophilic Chromophobe Renal Cell Carcinoma

Renal low-grade oncocytic tumor (LOT) is a recently recognized renal cell neoplasm designated within the "other oncocytic tumors" category in the 2022 World Health Organization classification system. Although the clinicopathologic, immunohistochemical, and molecular features reported for LOT have been largely consistent, the data are relatively limited. The morphologic overlap between LOT and other low-grade oncocytic neoplasms, particularly eosinophilic chromophobe renal cell carcinoma (E-chRCC), remains a controversial area in renal tumor classification. To address this uncertainty, we characterized and compared large cohorts of LOT (n = 67) and E-chRCC (n = 69) and revealed notable differences between the 2 entities. Clinically, LOT predominantly affected women, whereas E-chRCC showed a male predilection. Histologically, although almost all LOTs were dominated by a small-nested pattern, E-chRCC mainly showed solid and tubular architectures. Molecular analysis revealed that 87% of LOT cases harbored mutations in the tuberous sclerosis complex (TSC)-mTOR complex 1 (mTORC1) pathway, most frequently in MTOR and RHEB genes; a subset of LOT cases had chromosomal 7 and 19q gains. In contrast, E-chRCC lacked mTORC1 mutations, and 60% of cases displayed chromosomal losses characteristic of chRCC. We also explored the cell of origin for LOT and identified L1 cell adhesion molecule (L1CAM), a collecting duct and connecting tubule principal cell marker, as a highly sensitive and specific ancillary test for differentiating LOT from E-chRCC. This distinctive L1CAM immunohistochemical labeling suggests the principal cells as the cell of origin for LOT, unlike the intercalated cell origin of E-chRCC and oncocytoma. The ultrastructural analysis of LOT showed normal-appearing mitochondria and intracytoplasmic lumina with microvilli, different from what has been described for chRCC. Our study further supports LOT as a unique entity with a benign clinical course. Based on the likely cell of origin and its clinicopathologic characteristics, we propose that changing the nomenclature of LOT to "Oncocytic Principal Cell Adenoma of the Kidney" may be a better way to define and describe this entity.

Dual T cell receptor/chimeric antigen receptor engineered NK-92 cells targeting the HPV16 E6 oncoprotein and the tumor-associated antigen L1CAM exhibit enhanced cytotoxicity and specificity against tumor cells

The human papillomavirus type 16 (HPV16) causes a large fraction of genital and oropharyngeal carcinomas. To maintain the transformed state, the tumor cells must continuously synthesize the E6 and E7 viral oncoproteins, which makes them tumor-specific antigens. Indeed, specific T cell responses against them have been well documented and CD8+ T cells engineered to express T cell receptors (TCRs) that recognize epitopes of E6 or E7 have been tested in clinical studies with promising results, yet with limited clinical success. Using CD8+ T cells from peripheral blood of healthy donors, we have identified two novel TCRs reactive to an unexplored E618-26 epitope. These TCRs showed limited standalone cytotoxicity against E618-26-HLA-A*02:01-presenting tumor cells. However, a single-signaling domain chimeric antigen receptor (ssdCAR) targeting L1CAM, a cell adhesion protein frequently overexpressed in HPV16-induced cancer, prompted a synergistic effect that significantly enhanced the cytotoxic capacity of NK-92/CD3/CD8 cells armored with both TCR and ssdCAR when both receptors simultaneously engaged their respective targets, as shown by live microscopy of 2-D and 3-D co-cultures. Thus, virus-specific TCRs from the CD8+ T cell repertoire of healthy donors can be combined with a suitable ssdCAR to enhance the cytotoxic capacity of the effector cells and, indirectly, their specificity.

Evaluation of prognostic potential of β-catenin and L1CAM expression according to endometrial cancer risk group

OBJECTIVE

We investigate the prognostic role of β-catenin and L1 neuronal cell-adhesion molecule (L1CAM) according to risk groups in endometrial carcinomas (EC).

METHODS

A total of 335 EC patients were classified according to the Proactive Molecular Risk Classifier for Endometrial Cancer. We evaluated the expression of ß-catenin and L1CAM using immunohistochemistry, and their association with clinicopathological characteristics and survival.

RESULTS

The expressions of β-catenin and L1CAM were observed in 10.4% of all patients, respectively, and showed mutually exclusive pattern. While β-catenin expression was associated with endometrioid histology (p = 0.035) and low tumor grade (p = 0.045), L1CAM expression was associated with non-endometrioid histology (p < 0.001), high tumor grade (p < 0.001), lymphovascular space invasion (p = 0.006), and advanced International Federation of Gynecology and Obstetrics (FIGO) stage (p = 0.001). β-catenin expression was most frequent in the no specific molecular (NSMP) group (26/35, 74.3%), followed by the DNA polymerase-ε-mutated (POLE-mut) (6/35, 17.1%), and mismatch repair-deficiency (dMMR) (3/35, 8.6%). L1CAM expression was most frequent in the p53-abnormal group (22/35, 62.9%), followed by the NSMP (6/35, 17.1%), dMMR (4/35, 11.4%), and POLE-mut (3/35, 8.6%). Although both markers did not show statistical significance in multivariate analysis for both progression-free survival (PFS) and overall survival in entire cohort, β-catenin positivity was identified as the sole factor associated with worse PFS in the high-intermediate risk subgroup (p = 0.001).

CONCLUSION

The expression of nuclear β-catenin may serve as a potential biomarker for predicting recurrence and guiding therapeutic strategies in high-intermediate risk EC patients.

Reciprocal regulation of forkhead box C1 and L1 cell adhesion molecule contributes to triple-negative breast cancer progression

PURPOSE

The potential of targeting forkhead box C1 (FOXC1) as a therapeutic approach for triple-negative breast cancer (TNBC) is promising. However, a comprehensive understanding of FOXC1 regulation, particularly upstream factors, remains elusive. Expression of the L1 cell adhesion molecule (L1CAM), a transmembrane glycoprotein associated with brain metastasis, was observed to be positively associated with FOXC1 transcripts. Thus, this study aims to investigate their relationship in TNBC progression.

METHODS

Publicly available FOXC1 and L1CAM transcriptomic data were obtained, and their corresponding proteins were analyzed in four TNBC cell lines. In BT549 cells, FOXC1 and L1CAM were individually silenced, while L1CAM was overexpressed in BT549-shFOXC1, MDA-MB-231, and HCC1937 cells. CCK-8, transwell, and wound healing assays were performed in these cell lines, and immunohistochemical staining was conducted in tumor samples.

RESULTS

A positive correlation between L1CAM and FOXC1 transcripts was observed in publicly available datasets. In BT549 cells, knockdown of FOXC1 led to reduced L1CAM expression at both the transcriptional and protein levels, and conversely, silencing of L1CAM decreased FOXC1 protein levels, but interestingly, FOXC1 transcripts remained largely unaffected. Overexpressing L1CAM resulted in increased FOXC1 protein expression without significant changes in FOXC1 mRNA levels. This trend was also observed in BT549-shFOXC1, MDA-MB-231-L1CAM, and HCC1937-L1CAM cells. Notably, alterations in FOXC1 or L1CAM levels corresponded to changes in cell proliferation, migration, and invasion capacities. Furthermore, a positive correlation between L1CAM and FOXC1 protein expression was detected in human TNBC tumors.

CONCLUSION

FOXC1 and L1CAM exhibit co-regulation at the protein level, with FOXC1 regulating at the transcriptional level and L1CAM regulating at the post-transcriptional level, and together they positively influence cell proliferation, migration, and invasion in TNBC.

Optimizing drug combination and mechanism analysis based on risk pathway crosstalk in pan cancer

Combination therapy can greatly improve the efficacy of cancer treatment, so identifying the most effective drug combination and interaction can accelerate the development of combination therapy. Here we developed a computational network biological approach to identify the effective drug which inhibition risk pathway crosstalk of cancer, and then filtrated and optimized the drug combination for cancer treatment. We integrated high-throughput data concerning pan-cancer and drugs to construct miRNA-mediated crosstalk networks among cancer pathways and further construct networks for therapeutic drug. Screening by drug combination method, we obtained 687 optimized drug combinations of 83 first-line anticancer drugs in pan-cancer. Next, we analyzed drug combination mechanism, and confirmed that the targets of cancer-specific crosstalk network in drug combination were closely related to cancer prognosis by survival analysis. Finally, we save all the results to a webpage for query ( http://bio-bigdata.hrbmu.edu.cn/oDrugCP/ ). In conclusion, our study provided an effective method for screening precise drug combinations for various cancer treatments, which may have important scientific significance and clinical application value for tumor treatment.

Adoptive cell therapy in paediatric extracranial solid tumours: current approaches and future challenges

Immunotherapy has ignited hope to cure paediatric solid tumours that resist traditional therapies. Among the most promising methods is adoptive cell therapy (ACT). Particularly, ACT using T cells equipped with chimeric antigen receptors (CARs) has moved into the spotlight in clinical studies. However, the efficacy of ACT is challenged by ACT-intrinsic factors, like lack of activation or T cell exhaustion, as well as immune evasion strategies of paediatric solid tumours, such as their highly immunosuppressive microenvironment. Novel strategies, including ACT using innate-like lymphocytes, innovative cell engineering techniques, and ACT combination therapies, are being developed and will be crucial to overcome these challenges. Here, we discuss the main classes of ACT for the treatment of paediatric extracranial solid tumours, reflect on the available preclinical and clinical evidence supporting promising strategies, and address the challenges that ACT is still facing. Ultimately, we highlight state-of-the-art developments and opportunities for new therapeutic options, which hold great potential for improving outcomes in this challenging patient population.

Identification of potential molecular targets for the treatment of cluster 1 human pheochromocytoma and paraganglioma via comprehensive proteomic characterization

BACKGROUND

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors. New drug targets and proteins that would assist sensitive PPGL imagining could improve therapy and quality of life of patients with PPGL, namely those with recurrent or metastatic disease. Using a combined proteomic strategy, we looked for such clinically relevant targets among integral membrane proteins (IMPs) upregulated on the surface of tumor cells and non-membrane druggable enzymes in PPGL.

METHODS

We conducted a detailed proteomic analysis of 22 well-characterized human PPGL samples and normal chromaffin tissue from adrenal medulla. A standard quantitative proteomic analysis of tumor lysate, which provides information largely on non-membrane proteins, was accompanied by specific membrane proteome-aimed methods, namely glycopeptide enrichment using lectin-affinity, glycopeptide capture by hydrazide chemistry, and enrichment of membrane-embedded hydrophobic transmembrane segments.

RESULTS

The study identified 67 cell surface integral membrane proteins strongly upregulated in PPGL compared to control chromaffin tissue. We prioritized the proteins based on their already documented direct role in cancer cell growth or progression. Increased expression of the seven most promising drug targets (CD146, CD171, ANO1, CD39, ATP8A1, ACE and SLC7A1) were confirmed using specific antibodies. Our experimental strategy also provided expression data for soluble proteins. Among the druggable non-membrane enzymes upregulated in PPGL, we identified three potential drug targets (SHMT2, ARG2 and autotaxin) and verified their upregulated expression.

CONCLUSIONS

Application of a combined proteomic strategy recently presented as "Pitchfork" enabled quantitative analysis of both, membrane and non-membrane proteome, and resulted in identification of 10 potential drug targets in human PPGL. Seven membrane proteins localized on the cell surface and three non-membrane druggable enzymes proteins were identified and verified as significantly upregulated in PPGL. All the proteins have been previously shown to be upregulated in several human cancers, and play direct role in cancer progression. Marked upregulation of these proteins along with their localization and established direct roles in tumor progression make these molecules promising candidates as drug targets or proteins for sensitive PPGL imaging.

Clinical significance of L1CAM expression in metastatic tubo-ovarian high-grade serous carcinoma

OBJECTIVE

To analyze the expression and prognostic role of L1CAM in tubo-ovarian high-grade serous carcinoma (HGSC).

METHODS

L1CAM protein expression by immunohistochemistry was analyzed in 644 HGSC (413 effusions, 231 surgical specimens). Expression was analyzed for association with clinicopathologic parameters and survival.

RESULTS

L1CAM protein expression was found in 401/413 (97%) effusions and 209/231 (90%) surgical specimens, with significantly higher staining extent in effusions (p < 0.001). L1CAM protein expression in effusions was unrelated to clinicopathologic parameters (p > 0.05). In surgical specimens, higher L1CAM expression was significantly related to primary (intrinsic) chemoresistance (p = 0.017). High (>25%) L1CAM expression in HGSC effusions (p = 0.02), older patient age (p = 0.013), FIGO stage IV disease (p < 0.001) and larger residual disease volume (p = 0.001) were significantly associated with shorter overall survival (OS) in univariate analysis. In Cox multivariate analysis, only FIGO stage (p = 0.001) and residual disease volume (p = 0.003) were independent prognosticators of OS. L1CAM expression in effusions was unrelated to progression-free survival (PFS). There was no association between L1CAM expression in surgical specimens and survival.

CONCLUSION

L1CAM is overexpressed in HGSC effusions compared to surgical specimens. Its overexpression in effusions is significantly associated with shorter OS, but not independently of established prognostic factors such as FIGO stage and residual disease volume.

Unveiling the Neural Environment in Cancer: Exploring the Role of Neural Circuit Players and Potential Therapeutic Strategies

The regulation of the immune environment within the tumor microenvironment has provided new opportunities for cancer treatment. However, an important microenvironment surrounding cancer that is often overlooked despite its significance in cancer progression is the neural environment surrounding the tumor. The release of neurotrophic factors from cancer cells is implicated in cancer growth and metastasis by facilitating the infiltration of nerve cells into the tumor microenvironment. This nerve-tumor interplay can elicit cancer cell proliferation, migration, and invasion in response to neurotransmitters. Moreover, it is possible that cancer cells could establish a network resembling that of neurons, allowing them to communicate with one another through neurotransmitters. The expression levels of players in the neural circuits of cancers could serve as potential biomarkers for cancer aggressiveness. Notably, the upregulation of certain players in the neural circuit has been linked to poor prognosis in specific cancer types such as breast cancer, pancreatic cancer, basal cell carcinoma, and stomach cancer. Targeting these players with inhibitors holds great potential for reducing the morbidity and mortality of these carcinomas. However, the efficacy of anti-neurogenic agents in cancer therapy remains underexplored, and further research is necessary to evaluate their effectiveness as a novel approach for cancer treatment. This review summarizes the current knowledge on the role of players in the neural circuits of cancers and the potential of anti-neurogenic agents for cancer therapy.

Peptide-mediated inhibition of the transcriptional regulator Elongin BC induces apoptosis in cancer cells

Inhibition of protein-protein interactions (PPIs) via designed peptides is an effective strategy to perturb their biological functions. The Elongin BC heterodimer (ELOB/C) binds to a BC-box motif and is essential for cancer cell growth. Here, we report a peptide that mimics the high-affinity BC-box of the PRC2-associated protein EPOP. This peptide tightly binds to the ELOB/C dimer (k_D = 0.46 ± 0.02 nM) and blocks the association of ELOB/C with its interaction partners, both in vitro and in the cellular environment. Cancer cells treated with our peptide inhibitor showed decreased cell viability, increased apoptosis, and perturbed gene expression. Therefore, our work proposes that blocking the BC-box-binding pocket of ELOB/C is a feasible strategy to impair its function and inhibit cancer cell growth. Our peptide inhibitor promises novel mechanistic insights into the biological function of the ELOB/C dimer and offers a starting point for therapeutics linked to ELOB/C dysfunction.

L1 cell adhesion molecule may be a protective molecule for atrial fibrillation in patients with valvular heart disease

Background

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia. L1 cell adhesion molecule (L1CAM) served as a crucial regulator of signaling pathways. This research sought to examine the clinical value and functions of soluble L1CAM in the serum of AF patients.

Methods

In total, 118 patients (valvular heart disease patients [VHD, total: n = 93; AF: n = 47; sinus rhythm (SR): n = 46] and healthy controls [n = 25]) were recruited in this retrospective study. Plasma levels of L1CAM were detected by enzyme-linked immunosorbent assays. The Pearson's correlation approach, as applicable, was used for analyzing the correlations. The L1CAM was shown to independently serve as a risk indicator of AF in VHD after being analyzed by the multivariable logistic regression. To examine the specificity and sensitivity of AF, receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used. A nomogram was developed for the visualisation of the model. We further evaluate the prediction model for AF using calibration plot and decision curve analysis.

Results

The plasma level of L1CAM was substantially decreased in AF patients as opposed to healthy control and SR patients (healthy control = 46.79 ± 12.55 pg/ml, SR = 32.86 ± 6.11 pg/ml, AF = 22.48 ± 5.39 pg/ml; SR vs. AF, P < 0.001; control vs. AF, P < 0.001). L1CAM was significantly and negatively correlated with LA and NT-proBNP (LA: r = -0.344, P = 0.002; NT-proBNP: r = -0.380, P = 0.001). Analyses using logistic regression showed a substantial correlation between L1CAM and AF in patients with VHD (For L1CAM, Model 1: OR = 0.704, 95%CI = 0.607-0.814, P < 0.001; Model 2: OR = 0.650, 95% CI = 0.529-0.798, P < 0.001; Model 3: OR = 0.650, 95% CI = 0.529-0.798, P < 0.001). ROC analysis showed that inclusion of L1CAM in the model significantly improved the ability of other clinical indicators to predict AF. The predictive model including L1CAM, LA, NT-proBNP and LVDd had excellent discrimination and a nomogram was developed. The model had good the calibration and clinical utility.

Conclusion

L1CAM was shown to independently serve as a risk indicator for AF in VHD. In AF patients with VHD, the prognostic and predictive effectiveness of models incorporating L1CAM was satisfactory. Collectively, L1CAM may be a protective molecule for atrial fibrillation in patients with valvular heart disease.

Exosomal miR-214-3p from senescent osteoblasts accelerates endothelial cell senescence

BACKGROUND

Osteoporosis is a common systemic bone disease that leads to bone fragility and increases the risk of fracture. However, the pathogenesis of osteoporosis is considered to be highly complex. The exosomes can regulate the communication between cells. The specific mechanism of information transmission between osteoblasts and endothelial cells is worthy of further study.

METHODS

Exosomes were isolated and verified from senescent osteoblasts. The source and properties of exosomes were determined by TEM, particle size analysis and western blot. We established the co-culture model of endothelial cells and senescent osteoblasts. We used qRT-PCR to identify differentially expressed miRNAs. The functional changes of vascular endothelial cells were verified by cell transfection. β-Galactosidase cell senescence assay, Hoechst cell apoptosis assay, Ki67 cell proliferation assay and Transwell migration assay were used to verify cell senescence, apoptosis, proliferation, and migration. The potential target gene of miRNA was detected by bio-informatics pathway and double luciferase report.

RESULTS

We discovered that senescent osteoblasts could promote the senescence and apoptosis of vascular endothelial cells and inhibit their proliferation and migration. miR-214-3p was upregulated in senescent osteoblast-derived exosomes. miR-214-3p could effectively promote senescence and apoptosis of endothelial cells and inhibit proliferation and migration ability. L1CAM is a miR-214-3p direct target gene determined by bio-informatics and double luciferase report.

CONCLUSIONS

In conclusion, senescent osteoblast-derived exosomes can accelerate endothelial cell senescence through miR-214-3p/L1CAM pathway. Our experiments reveal the role of exosomes in the skeletal microenvironment.

Prognostic significance of L1CAM expression in addition to ProMisE in endometrial cancer

OBJECTIVE

To investigate the prognostic significance of L1 cell-adhesion molecule (L1CAM), β-catenin, and programmed death-ligand 1 (PD-L1) in endometrial cancer (EC) patients, with a focus on p53 wild-type subgroup, for additional risk stratification.

METHODS

This retrospective cohort study included EC patients classified according to Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE) who underwent primary surgical treatment at the single center between January 2014 and December 2018. Immunohistochemical staining was performed for four mismatch repair (MMR) proteins, p53, L1CAM, β-catenin, and PD-L1. DNA polymerase epsilon (POLE) mutation was detected by hot spot sequencing via droplet digital polymerase chain reaction. Survival outcome of each subgroup of L1CAM, β-catenin, and PD-L1 was measured according to their expression.

RESULTS

A total of 162 EC patients were included. Endometrioid histologic type and early-stage disease were 140 (86.4%) and 109 (67.3%), respectively. ProMisE classification assigned 48 (29.6%), 16 (9.9%), 72 (44.4%), and 26 (16.0%) patients to MMR-deficient, POLE-mutated, p53 wild-type, and p53 abnormal subgroups, respectively. L1CAM was identified as an independent poor prognostic factor for progression-free survival (PFS; adjusted hazard ratio [aHR], 3.207; 95% confidence interval (CI), 1.432-7.187; P = 0.005), whereas β-catenin and PD-L1 positivity were not associated with recurrence (P = 0.462 and P = 0.152, respectively). In p53 wild-type subgroup, L1CAM positivity was associated with worse PFS (aHR, 4.906; 95% CI, 1.685-14.287; P = 0.004).

CONCLUSION

L1CAM positivity was associated with poor prognosis in EC and further stratified the risk of recurrence in p53 wild-type subgroup, whereas β-catenin and PD-L1 were not informative for risk stratification.

ZNF133 is a potent suppressor in breast carcinogenesis through dampening L1CAM, a driver for tumor progression

Due to the complexity and heterogeneity of breast cancer, the therapeutic effects of breast cancer treatment vary between subtypes. Breast cancer subtypes are classified based on the presence of molecular markers for estrogen or progesterone receptors and human epidermal growth factor 2. Thus, novel, comprehensive, and precise molecular indicators in breast carcinogenesis are urgently needed. Here, we report that ZNF133, a zinc-finger protein, is negatively associated with poor survival and advanced pathological staging of breast carcinomas. Moreover, ZNF133 is a transcription repressor physically associated with the KAP1 complex. It transcriptionally represses a cohort of genes, including L1CAM, that are critically involved in cell proliferation and motility. We also demonstrate that the ZNF133/KAP1 complex inhibits the proliferation and invasion of breast cancer cells in vitro and suppresses breast cancer growth and metastasis in vivo by dampening the transcription of L1CAM. Taken together, the findings of our study confirm the value of ZNF133 and L1CAM levels in the diagnosis and prognosis of breast cancer, contribute to a deeper understanding of the regulation mechanism of ZNF133 for the first time, and provide a new therapeutic strategy and precise intervention target for breast cancer.

L1-CAM in Mucinous Ovarian Carcinomas and Borderline Tumors: Impact on Tumor Recurrence and Potential Role in Tumor Progression

Mucinous ovarian carcinoma (MOC) is a rare histotype of primary ovarian carcinoma. Frequent pathogenic molecular alterations include mutations in KRAS , TP53 , and overexpression of human epidermal growth factor receptor 2, but without having prognostic relevance. As L1-CAM (cell adhesion molecule) has previously shown prognostic relevance in other epithelial tumors of the female genital tract, we analyzed whether L1-CAM expression affected MOC prognosis. In addition, we investigated L1-CAM expression in mucinous borderline tumors (MBOTs) with and without adjacent MOC to identify its potential role in the pathogenesis of MOC. We examined a well-characterized collective of 39 MOCs by immunohistochemistry and compared their expression with clinicopathologic data. L1-CAM positivity was defined as any (even single-cell) positivity. Furthermore, we compared the L1-CAM expression in 20 MBOT regions adjacent to a MOC with that of 15 pure MBOTs. L1-CAM expression in MOC was significantly associated with recurrence, independent of tumor stage. Overall, 7/20 positive cases recurred versus 0/19 L1-CAM-negative cases ( P =0.032), showing a significant difference in time to progression. Furthermore, the presence of at least 1 defined molecular alteration (L1-CAM, aberrant p53, or human epidermal growth factor receptor 2) was found more frequently in the MBOT regions adjacent to a MOC (14/20) than in pure MBOTs (3/15) ( P =0.024). Expression of the tumor marker L1-CAM is frequent (51%) in MOC and is associated with tumor recurrence. The lack of L1-CAM may serve to characterize cases with a low risk of recurrence. Furthermore, the presence of specific molecular alterations in MBOTs is associated with adjacent carcinomas and may define potential pathways in tumor progression.

N-BAR and F-BAR proteins-endophilin-A3 and PSTPIP1-control clathrin-independent endocytosis of L1CAM

Recent advances in the field demonstrate the high diversity and complexity of endocytic pathways. In the current study, we focus on the endocytosis of L1CAM. This glycoprotein plays a major role in the development of the nervous system, and is involved in cancer development and is associated with metastases and poor prognosis. Two L1CAM isoforms are subject to endocytosis: isoform 1, described as a clathrin-mediated cargo; isoform 2, whose endocytosis has never been studied. Deciphering the molecular machinery of isoform 2 internalisation should contribute to a better understanding of its pathophysiological role. First, we demonstrated in our cellular context that both isoforms of L1CAM are mainly a clathrin-independent cargo, which was not expected for isoform 1. Second, the mechanism of L1CAM endocytosis is specifically mediated by the N-BAR domain protein endophilin-A3. Third, we discovered PSTPIP1, an F-BAR domain protein, as a novel actor in this endocytic process. Finally, we identified galectins as endocytic partners and negative regulators of L1CAM endocytosis. In summary, the interplay of the BAR proteins endophilin-A3 and PSTPIP1, and galectins fine tune the clathrin-independent endocytosis of L1CAM.

L1CAM promotes vasculogenic mimicry formation by miR-143-3p-induced expression of hexokinase 2 in glioma

In recent decades, antiangiogenic therapy, which blocks the supply of oxygen and nutrition to tumor cells, has become a promising clinical strategy for the treatment of patients with tumors. However, recent studies revealed that vasculogenic mimicry (VM), which is the process by which vascular morphological structures are formed by highly invasive tumor cells, has been considered a potential factor for the failure of antiangiogenic therapy in patients with tumors. Thus, inhibition of VM formation might be a potential target for improving the outcome of antiangiogenic strategies. However, the mechanism underlying VM formation is still incompletely elucidated. Herein, we report that L1CAM might be a critical regulator of VM formation in glioma, and might be associated with the resistance of glioma to antiangiogenic therapy. We found that the tumor-invasion and tube-formation capabilities of L1CAM-overexpressing cells were significantly enhanced in vitro and in vivo. In addition, the results indicated that miR-143-3p, which might directly target the 3'UTR of the hexokinase 2 (HK2) gene to regulate its protein expression, was subsequently involved in L1CAM-mediated VM formation by glioma cells. Further study revealed that the regulation of MMP2, MMP9, and VEGFA expression was involved in this process. Moreover, we identified that activation of the downstream PI3K/AKT signaling pathway of the L1CAM/HK2 cascade is critical for VM formation by glioma cells. Furthermore, we found that the combined treatment of anti-L1CAM neutralizing monoclonal antibody and bevacizumab increases efficacy beyond that of bevacizumab alone, and suppresses glioma growth in vivo, indicating that the inhibition of L1CAM-mediated VM formation might efficiently improve the effect of antiangiogenic treatment for glioma patients. Together, our findings demonstrated a critical role of L1CAM in regulating VM formation in glioma, and that L1CAM might be a potential target for ameliorating tumor resistance to antiangiogenic therapy in glioma patients.

Pericytes in the tumor microenvironment

Pericytes are a type of mural cell located between the endothelial cells of capillaries and the basement membrane, which function to regulate the capillary vasomotor and maintain normal microcirculation of local tissues and organs and have been identified as a significant component in the tumor microenvironment (TME). Pericytes have various interactions with different components of the TME, such as constituting the pre-metastatic niche, promoting the growth of cancer cells and drug resistance through paracrine activity, and inducing M2 macrophage polarization. While changes in the TME can affect the number, phenotype, and molecular markers of pericytes. For example, pericyte detachment from endothelial cells in the TME facilitates tumor cells in situ to invade the circulating blood and is beneficial to local capillary basement membrane enzymatic hydrolysis and endothelial cell proliferation and budding, which contribute to tumor angiogenesis and metastasis. In this review, we discuss the emerging role of pericytes in the TME, and tumor treatment related to pericytes. This review aimed to provide a more comprehensive understanding of the function of pericytes and the relationship between pericytes and tumors and to provide ideas for the treatment and prevention of malignant tumors.

Single-Cell and Transcriptome-Based Immune Cell-Related Prognostic Model in Clear Cell Renal Cell Carcinoma

Traditional studies mostly focus on the role of single gene in regulating clear cell renal cell carcinoma (ccRCC), while it ignores the impact of tumour heterogeneity on disease progression. The purpose of this study is to construct a prognostic risk model for ccRCC by analysing the differential marker genes related to immune cells in the single-cell database to provide help in clinical diagnosis and targeted therapy. Single-cell data and ligand-receptor relationship pair data were downloaded from related publications, and ccRCC phenotype and expression profile data were downloaded from TCGA and CPTAC. Based on the DEGs of each cluster acquired from single-cell data, immune cell marker genes, and ligand-receptor gene data, we constructed a multilayer network. Then, the genes in the network and the genes in TCGA were used to construct the WGCNA network, which screened out prognosis-associated genes for subsequent analysis. Finally, a prognostic risk scoring model was obtained, and CPTAC data showed that the effectiveness of this model was good. A nomogram based on the predictive model for predicting the overall survival was established, and internal validation was performed well. Our findings suggest that the predictive model built and based on the immune cell scRNA-seq will enable us to judge the prognosis of patients with ccRCC and provide more accurate directions for basic relevant research and clinical practice.

Pepsinogen/Proton Pump Co-Expression in Barrett's Esophageal Cells Induces Cancer-Associated Changes

EDUCATIONAL OBJECTIVE

At the conclusion of this presentation, participants should better understand the carcinogenic potential of pepsin and proton pump expression in Barrett's esophagus.

OBJECTIVE

Barrett's esophagus (BE) is a well-known risk factor for esophageal adenocarcinoma (EAC). Gastric H⁺ /K⁺ ATPase proton pump and pepsin expression has been demonstrated in some cases of BE; however, the contribution of local pepsin and proton pump expression to carcinogenesis is unknown. In this study, RNA sequencing was used to examine global transcriptomic changes in a BE cell line ectopically expressing pepsinogen and/or gastric H⁺ /K⁺ ATPase proton pumps.

STUDY DESIGN

In vitro translational.

METHODS

BAR-T, a human BE cell line devoid of expression of pepsinogen or proton pumps, was transduced by lentivirus-encoding pepsinogen (PGA5) and/or gastric proton pump subunits (ATP4A, ATP4B). Changes relative to the parental line were assessed by RNA sequencing.

RESULTS

Top canonical pathways associated with protein-coding genes differentially expressed in pepsinogen and/or proton pump expressing BAR-T cells included those involved in the tumor microenvironment and epithelial-mesenchymal transition. Top upstream regulators of coding transcripts included TGFB1 and ERBB2, which are associated with the pathogenesis and prognosis of BE and EAC. Top upstream regulators of noncoding transcripts included p300-CBP, I-BET-151, and CD93, which have previously described associations with EAC or carcinogenesis. The top associated disease of both coding and noncoding transcripts was cancer.

CONCLUSIONS

These data support the carcinogenic potential of pepsin and proton pump expression in BE and reveal molecular pathways affected by their expression. Further study is warranted to investigate the role of these pathways in carcinogenesis associated with BE.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:59-69, 2023.

L1CAM is required for early dissemination of fallopian tube carcinoma precursors to the ovary

Most ovarian high-grade serous carcinomas (HGSC) arise from Serous Tubal Intraepithelial Carcinoma (STIC) lesions in the distal end of the fallopian tube (FT). Formation of STIC lesions from FT secretory cells leads to seeding of the ovarian surface, with rapid tumor dissemination to other abdominal structures thereafter. It remains unclear how nascent malignant cells leave the FT to colonize the ovary. This report provides evidence that the L1 cell adhesion molecule (L1CAM) contributes to the ability of transformed FT secretory cells (FTSEC) to detach from the tube, survive under anchorage-independent conditions, and seed the ovarian surface. L1CAM was highly expressed on the apical cells of STIC lesions and contributed to ovarian colonization by upregulating integrins and fibronectin in malignant cells and activating the AKT and ERK pathways. These changes increased cell survival under ultra-low attachment conditions that mimic transit from the FT to the ovary. To study dissemination to the ovary, we developed a tumor-ovary co-culture model. We showed that L1CAM expression was important for FT cells to invade the ovary as a cohesive group. Our results indicate that in the early stages of HGSC development, transformed FTSECs disseminate from the FT to the ovary in a L1CAM-dependent manner.

pGlycoQuant with a deep residual network for quantitative glycoproteomics at intact glycopeptide level

Large-scale intact glycopeptide identification has been advanced by software tools. However, tools for quantitative analysis remain lagging behind, which hinders exploring the differential site-specific glycosylation. Here, we report pGlycoQuant, a generic tool for both primary and tandem mass spectrometry-based intact glycopeptide quantitation. pGlycoQuant advances in glycopeptide matching through applying a deep learning model that reduces missing values by 19-89% compared with Byologic, MSFragger-Glyco, Skyline, and Proteome Discoverer, as well as a Match In Run algorithm for more glycopeptide coverage, greatly expanding the quantitative function of several widely used search engines, including pGlyco 2.0, pGlyco3, Byonic and MSFragger-Glyco. Further application of pGlycoQuant to the N-glycoproteomic study in three different metastatic HCC cell lines quantifies 6435 intact N-glycopeptides and, together with in vitro molecular biology experiments, illustrates site 979-core fucosylation of L1CAM as a potential regulator of HCC metastasis. We expected further applications of the freely available pGlycoQuant in glycoproteomic studies.

Mitochondrial measures in neuronally enriched extracellular vesicles predict brain and retinal atrophy in multiple sclerosis

BACKGROUND

Mitochondrial dysfunction plays an important role in multiple sclerosis (MS) disease progression. Plasma extracellular vesicles are a potential source of novel biomarkers in MS, and some of these are derived from mitochondria and contain functional mitochondrial components.

OBJECTIVE

To evaluate the relationship between levels of mitochondrial complex IV and V activity in neuronally enriched extracellular vesicles (NEVs) and brain and retinal atrophy as assessed using serial magnetic resonance imaging (MRI) and optical coherence tomography (OCT).

METHODS

Our cohort consisted of 48 people with MS. NEVs were immunocaptured from plasma and mitochondrial complex IV and V activity levels were measured. Subjects underwent OCT every 6 months and brain MRI annually. The associations between baseline mitochondrial complex IV and V activities and brain substructure and retinal thickness changes were estimated utilizing linear mixed-effects models.

RESULTS

We found that higher mitochondrial complex IV activity and lower mitochondrial complex V activity levels were significantly associated with faster whole-brain volume atrophy. Similar results were found with other brain substructures and retinal layer atrophy.

CONCLUSION

Our results suggest that mitochondrial measures in circulating NEVs could serve as potential biomarkers of disease progression and provide the rationale for larger follow-up longitudinal studies.

Reclassification of endometrial cancer and identification of key genes based on neural-related genes

Endometrial cancer (EC) is the most common gynecologic malignancy, and its incidence has been increasing every year. Nerve signaling is part of the tumor microenvironment and plays an active role in tumor progression and invasion. However, the relationship between the expression of neural-related genes (NRGs) and prognosis in endometrial cancer remains unknown. In this study, we obtained RNA sequencing data of EC from The Cancer Genome Atlas (TCGA). Endometrial cancer was classified into two subtypes based on the expression of neural-associated genes (NRGs), with statistical differences in clinical stage, pathological grading, and prognosis. A prognostic prediction model was established by LASSO-Cox analysis, and the results showed that high expression of NRGs was associated with poor survival prognosis. Further, CHRM2, GRIN1, L1CAM, and SEMA4F were found to be significantly associated with clinical stage, immune infiltration, immune response, and important signaling pathways in endometrial cancer. The reclassification of endometrial cancer based on NRG expression would be beneficial for future clinical practice. The genes CHRM2, GRIN1, L1CAM, and SEMA4F might serve as potential biomarkers of EC prognosis.

Parkinson's Disease Derived Exosomes Aggravate Neuropathology in SNCA*A53T Mice

OBJECTIVE

Accumulation of α-synuclein (α-syn) in neurons is a prominent feature of Parkinson's disease (PD). Recently, researchers have considered that extracellular vesicles (EVs) may play an important role in protein exportation and propagation, and α-syn-containing EVs derived from the central nervous system (CNS) have been detected in peripheral blood. However, mechanistic insights into CNS-derived EVs have not been well-described.

METHODS

Likely neurogenic EVs were purified from the plasma of PD patients and healthy controls using a well-established immunoprecipitation assay with anti-L1CAM-coated beads. A Prnp-SNCAA53T transgenic PD mouse model was used to evaluate the neuronal pathology induced by PD-derived L1CAM-purified EVs. EV-associated microRNA (miRNA) profiling was used to screen for altered miRNAs in PD-derived L1CAM-purified EVs.

RESULTS

PD patient-derived L1CAM-purified (likely neurogenic) EVs facilitated α-syn pathology and neuron loss in Prnp-SNCAA53T transgenic PD mice. The miRNA, novel_miR_44438, was significantly increased in the PD group, which promoted α-syn accumulation and neuronal degeneration in a dose-dependent manner. Novel _miR_44438 directly targets NDST1 mRNA and inhibits the function of heparan sulfate, thus preventing exosome biogenesis and α-syn release from exosomes.

INTERPRETATION

Novel_miR_44438 in PD-derived L1CAM-purified EVs inhibits the α-syn efflux from neurons thereby promoting the pathological accumulation and aggregation of α-syn. ANN NEUROL 2022;92:230-245.

Glioma Stem Cells in Pediatric High-Grade Gliomas: From Current Knowledge to Future Perspectives

Simple Summary

Pediatric high-grade glioma (pHGG) has a dismal prognosis in which the younger the patient, the more restricted the treatments are, in regard to the incurred risks. Current therapies destroy many tumor cells but fail to target the highly malignant glioma stem cells (GSCs) that adapt quickly to give rise to recurring, treatment-resistant cancers. Despite a lack of consensus around an efficient detection, GSCs are well described in adult brain tumors but remain poorly investigated in pediatric cases, mostly due to their rarity. An improved knowledge about GSC roles in pediatric tumors would provide a key leverage towards the elimination of this sub-population, based on targeted treatments. The aim of this review is to sum up the state of art about GSCs in pHGG.

Abstract

In children, high-grade gliomas (HGG) and diffuse midline gliomas (DMG) account for a high proportion of death due to cancer. Glioma stem cells (GSCs) are tumor cells in a specific state defined by a tumor-initiating capacity following serial transplantation, self-renewal, and an ability to recapitulate tumor heterogeneity. Their presence was demonstrated several decades ago in adult glioblastoma (GBM), and more recently in pediatric HGG and DMG. In adults, we and others have previously suggested that GSCs nest into the subventricular zone (SVZ), a neurogenic niche, where, among others, they find shelter from therapy. Both bench and bedside evidence strongly indicate a role for the GSCs and the SVZ in GBM progression, fostering the development of innovative targeting treatments. Such new therapeutic approaches are of particular interest in infants, in whom standard therapies are often limited due to the risk of late effects. The aim of this review is to describe current knowledge about GSCs in pediatric HGG and DMG, i.e., their characterization, the models that apply to their development and maintenance, the specific signaling pathways that may underlie their activity, and their specific interactions with neurogenic niches. Finally, we will discuss the clinical relevance of these observations and the therapeutic advantages of targeting the SVZ and/or the GSCs in infants.

Tryptophan hydroxylase 1 drives glioma progression by modulating the serotonin/L1CAM/NF-κB signaling pathway

Background

Glioma is one of the main causes of cancer-related mortality worldwide and is associated with high heterogeneity. However, the key players determining the fate of glioma remain obscure. In the present study, we shed light on tumor metabolism and aimed to investigate the role of tryptophan hydroxylase 1 (TPH-1) in the advancement of glioma.

Method

Herein, the levels of TPH-1 expression in glioma tissues were evaluated using The Cancer Genome Atlas (TCGA) database. Further, the proliferative characteristics and migration ability of TPH-1 overexpressing LN229/T98G cells were evaluated. Additionally, we performed a cytotoxicity analysis using temozolomide (TMZ) in these cells. We also examined the tumor growth and survival time in a mouse model of glioma treated with chemotherapeutic agents and a TPH-1 inhibitor.

Results

The results of both clinical and experimental data showed that excess TPH-1 expression resulted in sustained glioma progression and a dismal overall survival in these patients. Mechanistically, TPH-1 increased the production of serotonin in glioma cells. The elevated serotonin levels then augmented the NF-κB signaling pathway through the upregulation of the L1-cell adhesion molecule (L1CAM), thereby contributing to cellular proliferation, invasive migration, and drug resistance. In vivo experiments demonstrated potent antitumor effects, which benefited further from the synergistic combination of TMZ and LX-1031.

Conclusion

Taken together, these data suggested that TPH-1 facilitated cellular proliferation, migration, and chemoresistance in glioma through the serotonin/L1CAM/NF-κB pathway. By demonstrating the link of amino acid metabolic enzymes with tumor development, our findings may provide a potentially viable target for therapeutic manipulation aimed at eradicating glioma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09569-2.

Antagonistic L1 Adhesion Molecule Mimetic Compounds Inhibit Glioblastoma Cell Migration In Vitro

Cell adhesion molecule L1 is a cell surface glycoprotein that promotes neuronal cell migration, fosters regeneration after spinal cord injury and ameliorates the consequences of neuronal degeneration in mouse and zebrafish models. Counter-indicative features of L1 were found in tumor progression: the more L1 is expressed, the more tumor cells migrate and increase their metastatic potential. L1′s metastatic potential is further evidenced by its promotion of epithelial–mesenchymal transition, endothelial cell transcytosis and resistance to chemo- and radiotherapy. These unfortunate features are indicated by observations that cells that normally do not express L1 are induced to express it when becoming malignant. With the aim to ameliorate the devastating functions of L1 in tumors, we designed an alternative approach to counteract tumor cell migration. Libraries of small organic compounds were screened using the ELISA competition approach similar to the one that we used for identifying L1 agonistic mimetics. Whereas in the former approach, a function-triggering monoclonal antibody was used for screening libraries, we here used the function-inhibiting monoclonal antibody 324 that reduces the migration of neurons. We now show that the L1 antagonistic mimetics anagrelide, 2-hydroxy-5-fluoropyrimidine and mestranol inhibit the migration of cultured tumor cells in an L1-dependent manner, raising hopes for therapy.

Colorectal liver metastasis: molecular mechanism and interventional therapy

Colorectal cancer (CRC) is one of the most frequently occurring malignancy tumors with a high morbidity additionally, CRC patients may develop liver metastasis, which is the major cause of death. Despite significant advances in diagnostic and therapeutic techniques, the survival rate of colorectal liver metastasis (CRLM) patients remains very low. CRLM, as a complex cascade reaction process involving multiple factors and procedures, has complex and diverse molecular mechanisms. In this review, we summarize the mechanisms/pathophysiology, diagnosis, treatment of CRLM. We also focus on an overview of the recent advances in understanding the molecular basis of CRLM with a special emphasis on tumor microenvironment and promise of newer targeted therapies for CRLM, further improving the prognosis of CRLM patients.

SIX1 reprograms myogenic transcription factors to maintain the rhabdomyosarcoma undifferentiated state

Rhabdomyosarcoma (RMS) is a pediatric muscle sarcoma characterized by expression of the myogenic lineage transcription factors (TFs) MYOD1 and MYOG. Despite high expression of these TFs, RMS cells fail to terminally differentiate, suggesting the presence of factors that alter their functions. Here, we demonstrate that the developmental TF SIX1 is highly expressed in RMS and critical for maintaining a muscle progenitor-like state. SIX1 loss induces differentiation of RMS cells into myotube-like cells and impedes tumor growth in vivo. We show that SIX1 maintains the RMS undifferentiated state by controlling enhancer activity and MYOD1 occupancy at loci more permissive to tumor growth over muscle differentiation. Finally, we demonstrate that a gene signature derived from SIX1 loss correlates with differentiation status and predicts RMS progression in human disease. Our findings demonstrate a master regulatory role of SIX1 in repression of RMS differentiation via genome-wide alterations in MYOD1 and MYOG-mediated transcription.

Transcription Factors Leading to High Expression of Neuropeptide L1CAM in Brain Metastases from Lung Adenocarcinoma and Clinical Prognostic Analysis

Background

There is a lack of understanding of the development of metastasis in lung adenocarcinoma (LUAD). This study is aimed at exploring the upstream regulatory transcription factors of L1 cell adhesion molecule (L1CAM) and to construct a prognostic model to predict the risk of brain metastasis in LUAD.

Methods

Differences in gene expression between LUAD and brain metastatic LUAD were analyzed using the Wilcoxon rank-sum test. The GRNdb (http://www.grndb.com) was used to reveal the upstream regulatory transcription factors of L1CAM in LUAD. Single-cell expression profile data (GSE131907) were obtained from the transcriptome data of 10 metastatic brain tissue samples. LUAD prognostic nomogram prediction models were constructed based on the identified significant transcription factors and L1CAM.

Results

Survival analysis suggested that high L1CAM expression was negatively significantly associated with overall survival, disease-specific survival, and prognosis in the progression-free interval (p < 0.05). The box plot indicates that high expression of L1CAM was associated with distant metastases in LUAD, while ROC curves suggested that high expression of L1CAM was associated with poor prognosis. FOSL2, HOXA9, IRF4, IKZF1, STAT1, FLI1, ETS1, E2F7, and ADARB1 are potential upstream transcriptional regulators of L1CAM. Single-cell data analysis revealed that the expression of L1CAM was found significantly and positively correlated with the expression of ETS1, FOSL2, and STAT1 in brain metastases. L1CAM, ETS1, FOSL2, and STAT1 were used to construct the LUAD prognostic nomogram prediction model, and the ROC curves suggest that the constructed nomogram possesses good predictive power.

Conclusion

By bioinformatics methods, ETS1, FOSL2, and STAT1 were identified as potential transcriptional regulators of L1CAM in this study. This will help to facilitate the early identification of patients at high risk of metastasis.

POU2F3 beyond thymic carcinomas: expression across the spectrum of thymomas hints to medullary differentiation in type A thymoma

The thymic medulla comprises various cell types, including tuft cells that are involved in innate immunity. We recently reported that in Western cohorts of patients, most thymic squamous cell carcinomas (TSQCCs), in contrast to thymomas, exhibit strong and extensive expression of tuft cell markers, including the tuft cell master regulator, POU2F3. On closer inspection of 94 thymomas that cover the full spectrum of thymoma histotypes, we now find by immunohistochemistry that approximately half of types A, AB, and B1 thymomas contain small numbers (< 10%) of cells expressing POU2F3, while most types B2 and B3 thymomas do not (p < 0.05). Further, in rarer types A and AB thymomas with adenoid growth pattern, POU2F3( +) cells formed aggregates and co-expressed KIT, as did the tumor cells in 100% (9/9) of TSQCCs expressing POU2F3. However, the expression of another tuft cell marker, L1CAM, still distinguished TSQCC from the spectrum of thymomas that were all L1CAM-negative. This study is the first to demonstrate the high frequency of POU2F3 expression in an Asian cohort of TSQCCs. The common occurrence of scattered POU2F3( +) cells in types A and AB thymomas hints at their variable degree of medullary differentiation and supports the historical hypothesis of the medullary nature of type A thymomas. Immunohistochemistry of L1CAM may be a valuable tool to differentiate TSQCCs from thymomas.

Catulin Based Reporter System to Track and Characterize the Population of Invasive Cancer Cells in the Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is an aggressive tumor with a poor prognosis due to late diagnosis and loco-regional metastasis. Partial or more complete epithelial-mesenchymal transition (EMT) plays a role in tumor progression; however, it remains a challenge to observe the EMT in vivo, due to its transient nature. Here, we developed a novel catulin promoter-based reporter system that allows us to isolate and characterize in vivo a small fraction of invasive cancer cells. The analyses of tumors revealed that Catulin-green fluorescent protein (GFP)-positive cells were enriched in clusters of cells at the tumor invasion front. A functional genomic study unveiled genes involved in cellular movement and invasion providing a molecular profile of HNSCC invasive cells. This profile overlapped partially with the expression of signature genes related to the partial EMT available from the single cell analysis of human HNSCC specimens, highlighting the relevance of our data to the clinical disease progression state. Interestingly, we also observed upregulations of genes involved in axonal guidance-L1 cell adhesion molecule (L1CAM), neuropilin-1, semaphorins, and ephrins, indicating potential interactions of cancer cells and neuronal components of the stroma. Taken together, our data indicated that the catulin reporter system marked a population of invasive HNSCC cells with a molecular profile associated with cancer invasion.

Druggable genetic targets in endometrial cancer✰,✰✰

BACKGROUND

FBXW7 is frequently somatically mutated in grade 3 endometrioid endometrial cancers (G3EECs) and serous endometrial cancers (SECs), high-risk cancers associated with poor prognosis. CRISPR-edited cell lines identified the proteomic and phosphoproteomic effects of FBXW7 mutation in 3 high-risk endometrial cancers (ECs), including altered protein levels of L1CAM and TGM2. This result is important because L1CAM and TGM2 are druggable proteins that could represent new therapeutic targets.

METHODS

We used cBioPortal for Cancer Genomics to analyze data in The Cancer Genome Atlas (TCGA). We used the UCSC Xena Browser to analyze gene expression. For differential gene expression analysis, the gene ontology molecular function 2018 version was used. The analysis was focused on determined genes.

RESULTS

FBXW7 mutations affect gene expression of L1CAM but are unrelated to TGM2 gene expression. L1CAM gene expression is significantly related to survival. Patients with lower L1CAM gene expression have better survival. FBXW7 mutations are unrelated to survival. TGM2 gene expression is unrelated to FBXW7 mutations. TGM2 gene expression is unrelated to survival, all tumor grades or grade 3 alone.

CONCLUSION

We agree with Urick et al. that L1CAM may be a promising druggable target in endometrial carcinoma. The lack of relationship of TGM2 expression with FBXW7 mutations and endometrial cancer survival suggests that TGM2 might not be of as much value as a druggable target, compared to L1CAM. However, the fact that a certain alteration is not prognostic for cancer survival does not necessarily mean that the alteration will not be targetable. More data, such as inhibition of each gene by calculating drug targetability, may be required to support this conclusion.

Fra-2 overexpression upregulates pro-metastatic cell-adhesion molecules, promotes pulmonary metastasis, and reduces survival in a spontaneous xenograft model of human breast cancer

Purpose

The transcription factor Fra-2 affects the invasive potential of breast cancer cells by dysregulating adhesion molecules in vitro. Previous results suggested that it upregulates the expression of E- and P-selectin ligands. Such selectin ligands are important members of the leukocyte adhesion cascade, which govern the adhesion and transmigration of cancer cells into the stroma of the host organ of metastasis. As so far, no in vivo data are available, this study was designed to elucidate the role of Fra-2 expression in a spontaneous breast cancer metastasis xenograft model.

Methods

The effect of Fra-2 overexpression in two stable Fra-2 overexpressing clones of the human breast cancer cell line MDA MB231 on survival and metastatic load was studied after subcutaneous injection into scid and E- and P-selectin-deficient scid mice.

Results

Fra-2 overexpression leads to a significantly shorter overall survival and a higher amount of spontaneous lung metastases not only in scid mice, but also in E- and P-deficient mice, indicating that it regulates not only selectin ligands, but also selectin-independent adhesion processes.

Conclusion

Thus, Fra-2 expression influences the metastatic potential of breast cancer cells by changing the expression of adhesion molecules, resulting in increased adherence to endothelial cells in a breast cancer xenograft model.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03812-2.

L1CAM is not a reliable predictor for lymph node metastases in endometrial cancer, but L1CAM positive patients benefit from radiotherapy

Purpose: Several studies evidenced the potential of L1CAM as a prognostic marker in endometrial cancer. The aim of this study was to investigate whether L1CAM can predict lymph node metastasis and could therefore be used preoperatively to identify patients with low to high-intermediate risk endometrial cancer who would profit from a lymphadenectomy and an adjuvant treatment. To avoid unnecessary morbidity, de-escalating strategies are still required.

Methods: Immunohistochemistry for L1CAM was performed on curettage or hysterectomy specimens from 212 patients diagnosed with endometrial cancer who were treated at the University Hospital Basel during 2011-2019. L1CAM expression was correlated with clinicopathological features such as histological subtype, FIGO stage, lymph node metastasis, lymphadenectomy, adjuvant treatment and outcome.

Results: Using a cut off ≥10%, L1CAM was positive in 41/212 patients (19.3%) and negative in 171/212 patients (80.7%). L1CAM was associated with high-risk features such as non-endometrioid histology, high tumour grade, and high FIGO stage. There was no significant correlation between L1CAM expression and lymph node metastasis. However, patients with L1CAM positive tumours showed improved disease-specific survival if treated with adjuvant radiotherapy.

Conclusion: Although L1CAM expression pointed towards aggressive tumour biology, preoperative L1CAM analysis did not add any substantial predictive information regarding lymph node metastasis in low to high-intermediate risk groups. Therefore, L1CAM status is not suitable to tailor the surgical algorithm for lymph node staging. Nevertheless, our results suggest that L1CAM could be used as a predictive biomarker to select patients who may benefit the most from adjuvant radiotherapy.

L1CAM promotes ovarian cancer stemness and tumor initiation via FGFR1/SRC/STAT3 signaling

BACKGROUND

Cancer stem cells (CSC) have been implicated in tumor progression. In ovarian carcinoma (OC), CSC drive tumor formation, dissemination and recurrence, as well as drug resistance, thus contributing to the high death-to-incidence ratio of this disease. However, the molecular basis of such a pathogenic role of ovarian CSC (OCSC) has been elucidated only to a limited extent. In this context, the functional contribution of the L1 cell adhesion molecule (L1CAM) to OC stemness remains elusive.

METHODS

The expression of L1CAM was investigated in patient-derived OCSC. The genetic manipulation of L1CAM in OC cells provided gain and loss-of-function models that were then employed in cell biological assays as well as in vivo tumorigenesis experiments to assess the role of L1CAM in OC cell stemness and in OCSC-driven tumor initiation. We applied antibody-mediated neutralization to investigate L1CAM druggability. Biochemical approaches were then combined with functional in vitro assays to study the molecular mechanisms underlying the functional role of L1CAM in OCSC.

RESULTS

We report that L1CAM is upregulated in patient-derived OCSC. Functional studies showed that L1CAM promotes several stemness-related properties in OC cells, including sphere formation, tumor initiation and chemoresistance. These activities were repressed by an L1CAM-neutralizing antibody, pointing to L1CAM as a druggable target. Mechanistically, L1CAM interacted with and activated fibroblast growth factor receptor-1 (FGFR1), which in turn induced the SRC-mediated activation of STAT3. The inhibition of STAT3 prevented L1CAM-dependent OC stemness and tumor initiation.

CONCLUSIONS

Our study implicate L1CAM in the tumorigenic function of OCSC and point to the L1CAM/FGFR1/SRC/STAT3 signaling pathway as a novel driver of OC stemness. We also provide evidence that targeting this pathway can contribute to OC eradication.

Shotgun-based proteomics of extracellular vesicles in Alzheimer's disease reveals biomarkers involved in immunological and coagulation pathways

Alzheimer's disease (AD) is the most common form of dementia and without readily available clinical biomarkers. Blood-derived proteins are routinely used for diagnostics; however, comprehensive plasma profiling is challenging due to the dynamic range in protein concentrations. Extracellular vesicles (EVs) can cross the blood-brain barrier and may provide a source for AD biomarkers. We investigated plasma-derived EV proteins for AD biomarkers from 10 AD patients, 10 Mild Cognitive Impairment (MCI) patients, and 9 healthy controls (Con) using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The ultracentrifuged EVs were washed and confirmed according to the MISEV2018 guidelines. Some AD patients presented with highly elevated FXIIIA1 (log₂ FC: 4.6, p-value: 0.005) and FXIIIB (log₂ FC: 4.9, p-value: 0.018). A panel of proteins was identified discriminating Con from AD (AUC: 0.91, CI: 0.67-1.00) with ORM2 (AUC: 1.00, CI: 1.00-1.00), RBP4 (AUC: 0.99, CI: 0.95-1.00), and HYDIN (AUC: 0.89, CI: 0.72-1.00) were found especially relevant for AD. This indicates that EVs provide an easily accessible matrix for possible AD biomarkers. Some of the MCI patients, with similar protein profiles as the AD group, progressed to AD within a 2-year timespan.

Long noncoding RNA landscapes specific to benign and malignant thyroid neoplasms of distinct histological subtypes

The main types of thyroid neoplasms, follicular adenoma (FA), follicular thyroid carcinoma (FTC), classical and follicular variants of papillary carcinoma (clPTC and fvPTC), and anaplastic thyroid carcinoma (ATC), differ in prognosis, progression rate and metastatic behaviour. Specific patterns of lncRNAs involved in the development of clinical and morphological features can be presumed. LncRNA landscapes within distinct benign and malignant histological variants of thyroid neoplasms were not investigated. The aim of the study was to discover long noncoding RNA landscapes common and specific to major benign and malignant histological subtypes of thyroid neoplasms. LncRNA expression in FA, FTC, fvPTC, clPTC and ATC was analysed with comprehensive microarray and RNA-Seq datasets. Putative biological functions were evaluated via enrichment analysis of coexpressed coding genes. In the results, lncRNAs common and specific to FTC, clPTC, fvPTC, and ATC were identified. The discovered lncRNAs are putatively involved in L1CAM interactions, namely, pre-mRNA processing (lncRNAs specific to FTC); PCP/CE and WNT pathways (lncRNAs specific to fvPTC); extracellular matrix organization (lncRNAs specific to clPTC); and the cell cycle (lncRNAs specific to ATC). Known oncogenic and suppressor lncRNAs (RMST, CRNDE, SLC26A4-AS1, NR2F1-AS1, and LINC00511) were aberrantly expressed in thyroid carcinomas. These findings enhance the understanding of lncRNAs in the development of subtype-specific features in thyroid cancer.

Role of L1CAM in retinoblastoma tumorigenesis: identification of novel therapeutic targets

The study presented focuses on the role of the neuronal cell adhesion molecule L1 cell adhesion molecule (L1CAM) in retinoblastoma (RB), the most common malignant intraocular childhood tumor. L1CAM is differentially expressed in a variety of human cancers and has been suggested as a promising therapeutic target. We likewise observed differential expression patterns for L1CAM in RB cell lines and patient samples. The two proteases involved in ectodomain shedding of L1CAM (L1CAM sheddases: ADAM10 and ADAM17) were likewise differentially expressed in the RB cell lines investigated, and an involvement in L1CAM processing in RB cells could be verified. We also identified ezrin, galectin-3, and fibroblast growth factor basic as L1CAM signaling target genes in RB cells. Lentiviral L1CAM knockdown induced apoptosis and reduced cell viability, proliferation, growth, and colony formation capacity of RB cells, whereas L1CAM-overexpressing RB cells displayed the opposite effects. Chicken chorioallantoic membrane assays revealed that L1CAM depletion decreases the tumorigenic and migration potential of RB cells in vivo. Moreover, L1CAM depletion decreased viability and tumor growth of etoposide-resistant RB cell lines upon etoposide treatment in vitro and in vivo. Thus, L1CAM and its processing sheddases are potential novel targets for future therapeutic RB approaches.

Neuroglian regulates Drosophila intestinal stem cell proliferation through enhanced signaling via the epidermal growth factor receptor

The Drosophila intestine is an excellent system for elucidating mechanisms regulating stem cell behavior. Here we show that the septate junction (SJ) protein Neuroglian (Nrg) is expressed in intestinal stem cells (ISCs) and enteroblasts (EBs) within the fly intestine. SJs are not present between ISCs and EBs, suggesting Nrg plays a different role in this tissue. We reveal that Nrg is required for ISC proliferation in young flies, and depletion of Nrg from ISCs and EBs suppresses increased ISC proliferation in aged flies. Conversely, overexpression of Nrg in ISC and EBs promotes ISC proliferation, leading to an increase in cells expressing ISC/EB markers; in addition, we observe an increase in epidermal growth factor receptor (Egfr) activation. Genetic epistasis experiments reveal that Nrg acts upstream of Egfr to regulate ISC proliferation. As Nrg function is highly conserved in mammalian systems, our work characterizing the role of Nrg in the intestine has implications for the treatment of intestinal disorders that arise due to altered ISC behavior.

Roles for growth factors and mutations in metastatic dissemination

Cancer is initiated largely by specific cohorts of genetic aberrations, which are generated by mutagens and often mimic active growth factor receptors, or downstream effectors. Once initiated cells outgrow and attract blood vessels, a multi-step process, called metastasis, disseminates cancer cells primarily through vascular routes. The major steps of the metastatic cascade comprise intravasation into blood vessels, circulation as single or collectives of cells, and eventual colonization of distant organs. Herein, we consider metastasis as a multi-step process that seized principles and molecular players employed by physiological processes, such as tissue regeneration and migration of neural crest progenitors. Our discussion contrasts the irreversible nature of mutagenesis, which establishes primary tumors, and the reversible epigenetic processes (e.g. epithelial-mesenchymal transition) underlying the establishment of micro-metastases and secondary tumors. Interestingly, analyses of sequencing data from untreated metastases inferred depletion of putative driver mutations among metastases, in line with the pivotal role played by growth factors and epigenetic processes in metastasis. Conceivably, driver mutations may not confer the same advantage in the microenvironment of the primary tumor and of the colonization site, hence phenotypic plasticity rather than rigid cellular states hardwired by mutations becomes advantageous during metastasis. We review the latest reported examples of growth factors harnessed by the metastatic cascade, with the goal of identifying opportunities for anti-metastasis interventions. In summary, because the overwhelming majority of cancer-associated deaths are caused by metastatic disease, understanding the complexity of metastasis, especially the roles played by growth factors, is vital for preventing, diagnosing and treating metastasis.

Sweet systems: technologies for glycomic analysis and their integration into systems biology

Found in virtually every organism, glycans are essential molecules that play important roles in almost every aspect of biology. The composition of glycome, the repertoire of glycans in an organism or a biological sample, is often found altered in many diseases, including cancer, infectious diseases, metabolic and developmental disorders. Understanding how glycosylation and glycomic changes enriches our knowledge of the mechanisms of disease progression and sheds light on the development of novel therapeutics. However, the inherent diversity of glycan structures imposes challenges on the experimental characterization of glycomes. Advances in high-throughput glycomic technologies enable glycomic analysis in a rapid and comprehensive manner. In this review, we discuss the analytical methods currently used in high-throughput glycomics, including mass spectrometry, liquid chromatography and lectin microarray. Concomitant with the technical advances is the integration of glycomics into systems biology in the recent years. Herein we elaborate on some representative works from this recent trend to underline the important role of glycomics in such integrated approaches to disease.

Metastasis-Initiating Cells and Ecosystems

Metastasis is initiated and sustained through therapy by cancer cells with stem-like and immune-evasive properties, termed metastasis-initiating cells (MIC). Recent progress suggests that MICs result from the adoption of a normal regenerative progenitor phenotype by malignant cells, a phenotype with intrinsic programs to survive the stresses of the metastatic process, undergo epithelial-mesenchymal transitions, enter slow-cycling states for dormancy, evade immune surveillance, establish supportive interactions with organ-specific niches, and co-opt systemic factors for growth and recurrence after therapy. Mechanistic understanding of the molecular mediators of MIC phenotypes and host tissue ecosystems could yield cancer therapeutics to improve patient outcomes. SIGNIFICANCE: Understanding the origins, traits, and vulnerabilities of progenitor cancer cells with the capacity to initiate metastasis in distant organs, and the host microenvironments that support the ability of these cells to evade immune surveillance and regenerate the tumor, is critical for developing strategies to improve the prevention and treatment of advanced cancer. Leveraging recent progress in our understanding of the metastatic process, here we review the nature of MICs and their ecosystems and offer a perspective on how this knowledge is informing innovative treatments of metastatic cancers.

L1CAM Expression in Recurrent Estrogen Positive/HER2 Negative Breast Cancer: A Novel Biomarker Worth Considering

We investigate L1 cell adhesion molecule (L1CAM) expression in estrogen receptor (ER)-positive/human epidermal growth factor receptor (HER2)-negative breast carcinomas. The finding of a potential correlation between high L1CAM expression and recurrent/metastatic disease in luminal A and B breast carcinomas may be helpful for risk stratification and open opportunities for targeted therapies. 304 cases comprising 152 cases of ER-positive, progesterone receptor (PR)-positive/negative, and HER2-negative recurrent/metastatic breast carcinomas and 152 nonrecurrent controls were included. ER, PR, HER-2, Ki-67 status, Nottingham grade, tumor size, tumor stage, number of foci, lymph node status, lymphovascular invasion, phenotype, laterality, age at diagnosis and first distant or local recurrence were recorded. L1CAM positive cases showed increased specificity for recurrence and these patients were significantly younger than L1CAM negative ones. Compared with L1CAM negative recurrent cases, L1CAM positive ones had a noticeably higher Ki-67, tended to be larger and recurred sooner. All L1CAM positive recurrent/metastatic cases were of the luminal B subtype compared with 67.3% of the L1CAM negative cases. L1CAM is highly specific for recurrence in a subset of breast cancer patients and may be associated with more aggressive behavior, particularly in luminal B breast cancers with higher Ki-67 expression. Further investigation about the prognostic value of L1CAM is warranted.