Progression Of Human Cancers Research Articles

Long noncoding RNA PVT1 predicts poor prognosis and promotes the progression of colorectal cancer through the miR-24-3p/NRP1 axis in zebrafish xenografts.

Long noncoding RNAs (lncRNAs) play important roles in the progression of human cancer. It is reported that lncRNA plasmacytoma variant translocation 1 (PVT1) is involved in colorectal cancer (CRC), however, the underlying mechanism remains to be explored deeply, especially by in vivo models. In the present study, bioinformatics analysis showed that the expression level of PVT1 was upregulated in CRC tissues and highly associated with poor prognosis of CRC patients. In cultured CRC cells, knockdown of PVT1 inhibited cell proliferation and migration of CRC cells, while overexpression of PVT1 promoted the progression of CRC cells. In zebrafish xenografts, the silencing of PVT1 also suppressed the growth and metastasis of CRC cells. For mechanism studies, the binding relationships among PVT1, miR-24-3p, and Neuropilin 1 (NRP1) were predicted by starBase firstly. The luciferase reporter assays verified that PVT1 and NRP1 could bind with miR-24-3p directly. Further studies showed miR-24-3p negatively regulated the progression of CRC cells, the inhibition of miR-24-3p counteracted the repression effects of CRC progression when knocking down PVT1. In addition, the expression of NRP1 was regulated by PVT1, and NRP1 overexpression could partially rescue the inhibition effects of CRC progression when knocking down PVT1 in vitro and in vivo. Our study reveals that PVT1 promotes the proliferation and metastasis of CRC via regulating the miR-24-3p/NRP1 axis, which provides a prognosis biomarker and a potential therapeutic target for CRC patients.

Phosphofructokinase Platelet Overexpression Accelerated Colorectal Cancer Cell Growth and Motility.

Background: Glycolysis is a glucose metabolism pathway that generates the high-energy compound adenosine triphosphate, which supports cancer cell growth. Phosphofructokinase platelet (PFKP) plays a crucial role in glycolysis regulation and is involved in human cancer progression. However, the biological function of PFKP remains unclear in colorectal cancer (CRC). Methods: We analyzed the expression levels of PFKF in colon cancer cells and clinical samples using real-time PCR and western blot techniques. To determine the clinical significance of PFKP expression in colorectal cancer (CRC), we analyzed public databases. In addition, we conducted in vitro assays to investigate the effects of PFKP on cell growth, cell cycle, and motility. Results: An analysis by the Cancer Genome Atlas database revealed that PFKP was significantly overexpressed in CRC. We examined the levels of PFKP mRNA and protein, revealing that PFKP expression was significantly increased in CRC. The results of the univariate Cox regression analysis showed that high PFKP expression was linked to worse disease-specific survival (DSS) and overall survival (OS) [DSS: crude hazard ratio (CHR) = 1.84, 95% confidence interval (CI): 1.01-3.36, p = 0.047; OS: CHR=1.91, 95% CI: 1.06-3.43, p = 0.031]. Multivariate Cox regression analysis revealed that high PFKP expression was an independent prognostic biomarker for the DSS and OS of patients with CRC (DSS: adjusted HR = 2.07, 95% CI: 1.13-3.79, p = 0.018; AHR = 2.34, 95% CI: 1.29-4.25, p = 0.005). PFKP knockdown reduced the proliferation, colony formation, and invasion of CRC cells. In addition, the knockdown induced cell cycle arrest at the G0/G1 phase by impairing cell cycle-related protein expression. Conclusion: Overexpression of PFKP contributes to the growth and invasion of CRC by regulating cell cycle progression. PFKP expression can serve as a valuable molecular biomarker for cancer prognosis and a potential therapeutic target for treating CRC.

Mechanism and function of miR-140 in human cancers: A review and in silico study.

MicroRNA-140 (miR-140) acts as a tumor suppressor and plays a vital role in cell biological functions such as cell proliferation, apoptosis, and DNA repair. The expression of this miRNA has been shown to be considerably decreased in cancer tissues and cell lines compared with normal adjacent tissues. Consequently, aberrant expression of some miR-140 target genes can lead to the initiation and progression of various human cancers, such as breast cancer, gastrointestinal cancers, lung cancer, and prostate cancer. The dysregulation of the miR-140 network also affects cell proliferation, invasion, metastasis, and apoptosis of cancer cells by affecting various signaling pathways. Besides, up-regulation of miR-140 could enhance the efficacy of chemotherapeutic agents in different cancer. We aimed to cover most aspects of miR-140 function in cancer development and address its importance in different stages of cancer progression.

Immunohistochemical Evaluation of COL11A1 and FGD3 Expression in Invasive Breast Cancer

Background: Collagen type XI, alpha 1 (COL11A1) is a minor component of extracellular matrix and its overexpression is associated with tumoral progression and poorer outcome in several human cancers; data on breast cancer are promising but scarce. FGD3 expression has been shown to be a strong independent prognostic factor in breast cancer. The aim of our study was to investigate whether COL11A1 expression correlates with other classic pathologic prognostic factors including FGD3 expression, as well as with clinical outcome, to evaluate its potential use as prognostic factor in breast cancer patients. Methods: We evaluated by immunohistochemistry COL11A1 expression and we studied the relationship between this protein expression and traditional breast cancer prognostic factors, FGD3 expression, as well as with patients’ outcome. Results: We found that higher stromal COL11A1 expression was associated with higher tumour grade (G3) (p = 0.001), higher Ki67 proliferation index (p = 0.006), more advanced AJCC stage (p = 0.031) and lower FGD3 expression (p = 0.039). In a case-control analysis, we observed that patients with high-COL11A1 had a higher risk of recurrence (OR = 2.0) and of dying of the disease (OR = 2.0). Patients with high-COL11A1-expressing tumours had shorter disease-free survival and overall survival (difference not significant). There was a linear positive correlation between COL11A1 expression on epithelial tumoral cells and surrounding stromal cells (r = 0.247, p = 0.04). Conclusion: Our findings suggest that COL11A1 may represent a marker of aggressiveness in invasive breast cancer and that its detection warrants further study on larger series to evaluate its possible use in clinical practice.

Britannin Induces Autophagy-Dependent Apoptosis via the Reactive Oxygen Species/Adenosine 5′-monophosphate-Activated Protein Kinase-unc-51-Like Autophagy Activating Kinase 1 Axis in Cervical Cancer as Detected Using Nanomagnetic Beads

Cervical cancer is a unique and common malignancy that occurs in women. Britannin has been proven to inhibit the progression of human liver and breast cancers. However, its efficacy in cervical cancer is still unclear. Human cervical squamous cell carcinoma SiHa cells were used to analyze the effect of britannin administration on cervical tumors by xenotransplantation of human tumor cells. The Cell Counting Kit-8 was used to determine the half maximal inhibitory concentration (IC50) of britannin on SiHa, and the cell invasion ability was measured using Transwell invasion assay. Cell migration was measured using the scratch-healing assay, while the clonogenic assay was performed to determine cell proliferation. Dichloro-dihydro-fluorescein diacetate was used to label reactive oxygen species (ROS) in cells or tissues. Intracellular autophages were stained with monodansylcadaverine. Western blotting assisted by nanomagnetic beads was performed to study the expression of p62, light chain 3 beta (LC3B), Beclin 1, and autophagy-related protein 5 (ATG5) in cells or tissues, as well as the phosphorylation of AMP-activated protein kinase (AMPK) and unc-51-like autophagy activating kinase 1 (ULK1). Hematoxylin and eosin staining was performed to analyze the pathological changes in the tumor cells. The expression of Ki-67, B-cell lymphoma 2 (Bcl-2), and Bax in the tumor cells was analyzed by immunohistochemistry. The IC50 obtained for britannin against SiHa was 10.01 μM. Britannin inhibited the proliferation, invasion, and migration of SiHa cells, and promoted the generation and autophagy of ROS in tumor cells and tissues. Furthermore, p-AMPK/AMPK and p-ULK1/ULK1, LC3B, Beclin 1, and ATG5 were upregulated, whereas p62 was downregulated in cells and tissues. Tumor development was inhibited; tissue inflammation was reduced; Ki-67 and Bcl-2 expression was downregulated; and Bax expression was upregulated. The expression of cleaved caspase-3, cleaved poly-ADP-ribose polymerases, and voltage-dependent anion-selective channel 1 was upregulated. These effects can be partially reversed by the AMPK inhibitor dorsomorphin dihydrochloride (BML-275). In vivo and in vitro studies showed that britannin upregulated the of ROS content of human cervical squamous cell carcinoma cells, leading to significant autophagy, thereby inhibiting the occurrence and development of cervical squamous cell carcinoma. The mechanism may be related to the ROS/AMPK/ULK1 signaling pathway.

LINC00460 Facilitates Cell Proliferation and Inhibits Ferroptosis in Breast Cancer Through the miR-320a/MAL2 Axis.

Background: Emerging evidence suggests that long noncoding RNAs (lncRNAs) play an important role in the progression of multiple human cancers including breast cancer. In this study, we aimed to research novel functions of long intergenic noncoding RNA 460 (LINC00460) on cell proliferation and ferroptosis in breast cancer. Method: UALCAN, TANRIC, and GSE16446 data were used to analyze the expression of LINC00460 in breast cancer tissues. Furthermore, real-time quantitative PCR, western blot, cell proliferation assay, iron assay, and malondialdehyde (MDA) assay were applied to detect the function and mechanism of particular molecules. Results: The LINC00460 expression was significantly increased in breast cancer tissues compared with normal tissues. Importantly, patients with high LINC00460 expression showed a longer overall survival rate. LINC00460 knockdown markedly suppressed the proliferation of breast cancer cells and promoted ferroptosis. Mechanistic analysis revealed that LINC00460 promoted myelin and lymphocyte protein 2 (MAL2) expression by sponging miR-320a. Moreover, both miR-320a knockdown and MAL2 overexpression could reverse the effects of LINC00460 silencing on cell proliferation and ferroptosis. Conclusions: In summary, our results reveal an alternative mechanism by which breast cancer cells can acquire resistance to ferroptosis via the LINC00460/miR-320a/MAL2 axis.

PRMT5/FGFR3/AKT Signaling Axis Facilitates Lung Cancer Cell Metastasis.

Objectives: This study aims to investigate the function of the protein arginine methyltransferase 5 (PRMT5) and fibroblast growth factor receptor 3 (FGFR3)/Akt signaling axis in the epithelial-mesenchymal transition (EMT) of human lung cancer. Methods: The mRNA and protein expression levels of PRMT5, FGFR3, p-Akt, and EMT markers are determined by quantitative real-time PCR and Western blotting, respectively; the expression and localization of PRMT5, p-Akt, and proliferating cell nuclear antigen are detected by immunofluorescence; the human lung cancer cell proliferation is measured by MTS assay. Results: PRMT5 and FGFR3 are highly expressed in human lung cancer tissues and are closely related to lymphatic metastasis. Moreover, down-regulation of PRMT5 by lentivirus-mediated shRNAs or inhibition of PRMT5 by specific inhibitors attenuates FGFR3 expression, Akt phosphorylation, and lung cancer cell proliferation. Further studies show that silencing PRMT5 impairs EMT-related markers, including vimentin, collagen I, and β-catenin. Conversely, ectopic expression of PRMT5 increases FGFR3 expression, Akt phosphorylation, and EMT-related markers, suggesting that PRMT5 regulates metastasis probably through the FGFR3/Akt signaling axis. Conclusion: PRMT5/FGFR3/Akt signaling axis controls human lung cancer progression and metastasis and also implies that PRMT5 may serve as a prognostic biomarker and therapeutic candidate for treating lung cancer.

LINC01023 Promotes the Hepatoblastoma Tumorigenesis via miR-378a-5p/WNT3 Axis.

Hepatoblastoma is the most common type of hepatic tumors occurring in children between 0 and 5years. And the exact pathophysiology of the disease is still mysterious. Accumulating studies on LncRNA have shown its pivotal role in the development and progression of distinct human cancers. However, the role of LINC01023 in hepatoblastoma is unknown. The relative expression of LINC01023, miR-378a-5p, and Wnt3 on hepatoblastoma tissue and cell lines was determined by quantitative polymerase chain reaction (qRT-PCR). The effect of LINC01023 downregulation and upregulation on cell proliferation, colony formation and apoptosis activities in HUH6 and HepG2 Cells was assessed by CKK8, clonogenic and flow cytometry analysis, respectively. Dual luciferase, RNA immunoprecipitation (RIP), and RNA pull-down were performed to confirm the interaction between LINC01023 and miR-378a-5p. Similarly, Dual luciferase assay was performed to confirmed the interaction between Wnt3 and miR-378a-5p. The xenograft tumorgenicity test was performed to elucidate the tumorgenicity potential of LINC01023. LINC01023 was significantly upregulated in hepatoblastoma tissue and cell lines rather than in adjacent normal hepatic tissue and QSG7701 cell lines. LINC01023 silencing attenuated cell proliferation, colony formation and increased cell apoptosis. Conversely, LINC01023 upregulation results in significant increase in cell proliferation, and colony formation activities however, a significant reduction in apoptosis activity was reported. Interaction between the LINC01023 and WNT3 was confirmed by dual luciferase assay. Xenograft animal tumorgenicity test confirmed the in-vivo tumorigenesis potential of LINC01203. To the best of our knowledge, this study is the first study demonstrating the role of LINC01023 in hepatoblastoma tumorigenesis through the LINC01023/miR-378a-5p/Wnt3 axis. It could be a potential therapeutic target and a prognostic biomarker in hepatoblastoma.

Multi-Transcriptomic Analysis Reveals the Heterogeneity and Tumor-Promoting Role of SPP1/CD44-Mediated Intratumoral Crosstalk in Gastric Cancer.

GC is a fatal disease with high heterogeneity and invasiveness. Recently, SPP1 has been reported to be involved in the tumor progression of multiple human cancers; however, the role of SPP1 in GC heterogeneity and whether it is associated with the invasiveness and mortality of GC remain unclear. Here, we combined multiple RNA sequencing approaches to evaluate the impact of SPP1 on GC. Through bulk RNA sequencing (bulk RNA-seq) and immunohistochemistry (IHC), we found that SPP1 was highly expressed in GC, and high levels of SPP1 were associated with macrophage infiltration, an advanced tumor stage, and higher mortality for advanced GC patients. Furthermore, through simultaneous single-cell and spatial analysis, we demonstrated that SPP1+ macrophages are tumor-specific macrophages unique to cancer and enriched in the deep layer of GC tissue. Cell-cell communication analysis revealed that SPP1/CD44 interactions between SPP1+ macrophages and their localized tumor epithelial cells could activate downstream target genes in epithelial cells to promote dynamic changes in intratumor heterogeneity. Moreover, these activated genes were found to be closely associated with poor clinical GC outcomes and with cancer-related pathways that promote GC progression, as shown by survival analysis and enrichment analysis, respectively. Collectively, our study reveals that tumor-specific SPP1+ macrophages drive the architecture of intratumor heterogeneity to evolve with tumor progression and that SPP1 may serve as a prognostic marker for advanced GC patients, as well as a potential therapeutic target for GC.

In vitro Anti-malignant Property of PCMT1 Silencing and Identification of the SNHG16/miR-195/PCMT1 Regulatory Axis in Breast Cancer Cells

BackgroundProtein L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1) is a highly conserved protein repair enzyme that participates in regulating the progression of human cancers. We therefore studied the function and the related mechanisms of PCMT1 in breast cancer cells. MethodsExpression profile and prognostic analysis of PCMT1 in breast cancer patients were analyzed using online databases. PCMT1 expression in breast cancer cells was detected by western blot analysis. Cell proliferation was determined by CCK-8 and colony formation assays. Apoptosis was evaluated using flow cytometry analysis and caspase-3/7 activity assay. Cell invasion was assessed by Transwell invasion assay. The small nucleolar RNA host gene 16 (SNHG16)/miR-195/PCMT1 regulatory axis was identified using bioinformatics analysis. ResultsPCMT1 expression was increased in breast cancer tissues and cells. High PCMT1 expression was correlated with poor prognosis in breast cancer patients. PCMT1 knockdown suppressed cell proliferation and colony formation ability in breast cancer cells. Moreover, PCMT1 knockdown induced apoptosis and restrained the invasive ability in breast cancer cells. PCMT1 overexpression increased the proliferative and invasive abilities of breast cancer cells. miR-195 was identified as the unique upstream miRNA of PCMT1. SNHG16 was identified as the unique upstream lncRNA of miR-195. SNHG16 knockdown downregulated PCMT1 by increasing miR-195 expression. Breast cancer cell proliferation was regulated by the SNHG16/miR-195/PCMT1 axis. ConclusionPCMT1 silencing inhibited cell proliferation and invasion and induced apoptosis in breast cancer cells and the SNHG16/miR-195/PCMT1 regulatory axis might serve as a potential therapeutic target for breast cancer.

Timosaponin AIII Inhibits Migration and Invasion Abilities in Human Cervical Cancer Cells through Inactivation of p38 MAPK-Mediated uPA Expression In Vitro and In Vivo

Cervical cancer is one of the most common gynecologic cancers globally that require novel approaches. Timosaponin AIII (TSAIII) is a steroidal saponin that displays beneficial effects in antitumor activities. However, the effect of TSAIII on human cervical cancer remains unknown. In this study, we found that TSAIII showed no influence on cell viability, cytotoxicity, cell cycle distribution and apoptosis induction in human cervical cancer cells. TSAIII was revealed to have a significant inhibitory effect on cell migration and invasion through the downregulation of invasion-related uPA expression and p38 MAPK activation in both human cervical cancer cells and cervical cancer stem cells (CCSCs), indicating that the p38 MAPK-uPA axis mediated the TSAIII-inhibited capacity of cellular migration and invasion. In a synergistic inhibition assay, a TSAIII plus p38 siRNA cotreatment revealed a greater inhibition of uPA expression, migration and invasion in human cervical cancer cells. In an immunodeficient mouse model, TSAIII significantly inhibited lung metastases from human cervical cancer SiHa cells without TSAIII-induced toxicity. These findings first revealed the inhibitory effects of TSAIII on the progression of human cervical cancer through its downregulation of p38 MAPK-uPA axis activation. Therefore, TSAIII might provide a potential strategy for auxiliary therapy in human cervical cancer.

Altered vaginal eukaryotic virome is associated with different cervical disease status

Viruses are important components of the human body. Growing evidence suggests that they are engaged in the physiology and disease status of the host. Even though the vaginal microbiome is involved in human papillomavirus (HPV) infection and cervical cancer (CC) progression, little is known about the role of the vaginal virome. In this pilot exploratory study, using unbiased viral metagenomics, we aim to investigate the vaginal eukaryotic virome in women with different levels of cervical lesions, and examine their associations with different cervical disease status. An altered eukaryotic virome was observed in women with different levels of lesions and Lactobacillus profiles. Anelloviruses and papillomaviruses are the most commonly detected eukaryotic viruses of the vaginal virome. Higher abundance and richness of anelloviruses and papillomaviruses were associated with low-grade squamous intraepithelial lesion (LSIL) and CC. Besides, higher anellovirus abundance was also associated with lactobacillus-depleted microbiome profiles and bacterial community state (CST) type IV. Furthermore, increased correlations between Anelloviridae and Papillomaviridae occurred in the women with increased cervical disease severity level from LSIL to CC. These data suggest underlying interactions between different microbes as well as the host physiology. Higher abundance and diversity of both anelloviruses and papillomaviruses shared by LSIL and CC suggest that anellovirus may be used as a potential adjunct biomarker to predict the risk of HPV persistent infection and/or CC. Future studies need to focus on the clinical relevance of anellovirus abundance with cervical disease status, and the evaluation of their potential as a new adjunct biomarker for the prediction and prognoses of CC.

Inhibition of dopamine receptor D1 signaling promotes human bile duct cancer progression via WNT signaling.

Bile duct cancer (BDC) frequently invades the nerve fibers, making complete surgical resection difficult. A single tumor mass contains cells of variable malignancy and cell-differentiation states, with cancer stem cells (CSCs) considered responsible for poor clinical outcomes. This study aimed to investigate the contribution of autosynthesized dopamine to CSC-related properties in BDC. Sphere formation assays using 13 commercially available BDC cell lines demonstrated that blocking dopamine receptor D1 (DRD1) signaling promoted CSC-related anchorage-independent growth. Additionally, we newly established four new BDC patient-derived organoids (PDOs) and found that blocking DRD1 increased resistance to chemotherapy and enabled xenotransplantation in vivo. Single-cell analysis revealed that the BDC PDO cells varied in their cell-differentiation states and responses to dopamine signaling. Further, DRD1 inhibition increased WNT7B expression in cells with bile duct-like phenotype, and it induced proliferation of other cell types expressing Wnt receptors and stem cell-like signatures. Reagents that inhibited Wnt function canceled the effect of DRD1 inhibition and reduced cell proliferation in BDC PDOs. In summary, in BDCs, DRD1 is a crucial protein involved in autonomous CSC proliferation through the regulation of endogenous WNT7B. As such, inhibition of the DRD1 feedback signaling may be a potential treatment strategy for BDC.

Exosomal microRNAs in the DLK1-DIO3 imprinted region derived from cancer-associated fibroblasts promote progression of hepatocellular carcinoma by targeting hedgehog interacting protein.

Hepatocellular carcinoma (HCC) is the sixth most commonly diagnosed cancer and third leading cause of cancer-related death worldwide in 2020. Exosomes derived from cancer-associated fibroblasts (CAFs-exo) can promote tumor progression in various human cancers. However, the underlying regulatory mechanism controlling how CAFs-exo can promote HCC progression remains poorly understood. CAFs and para-cancer fibroblasts (PAFs) were isolated from HCC tissues and corresponding para-cancer tissues, then were cultured in vitro. CAFs and PAFs were characterized by immunofluorescence and western blot (WB) assays. Exosomes were isolated by ultracentrifugation, and characterized by transmission electron microscopy, nanoflow cytometry, and WB assay. The internalization of exosomes by HCC cells was observed under a fluorescence microscope. Cell Counting Kit-8 (CCK-8) assay was used to evaluate cell proliferation. Wound healing and transwell assays were used for migration and invasion experiments. RT-PCR assay was used to examine differentially expressed microRNAs (miRNAs) in exosomes and HCC cells. The TargetScan database was used to predict miRNA target genes. Hedgehog interacting protein (HHIP) expression analysis, prognostic analysis, and enrichment analysis of HHIP-related co-expressed genes were performed using the TIMER, UALCAN, Kaplan-Meier plotter, and LinkedOmics databases. CAFs-exo were internalized by HCC cells. CAFs-exo contributed to the aggressive phenotype of HCC cells, while inhibiting exosome secretion reversed these effects. Mechanistically, miRNAs in the DLK1-DIO3 imprinted region (miR-329-3p, miR-380-3p, miR-410-5p, miR-431-5p) were increased in HCC cells co-cultured with CAFs-exo compared with PAFs-exo. Expression of HHIP, a possible miR-431-5p target gene, was significantly downregulated in HCC cells. Low HHIP expression level in tumor tissues could predict poor prognosis in HCC patients. HHIP-related co-expressed genes were mainly associated with cell adhesion molecules. CAFs-exo can promote HCC progression by delivering miRNAs in the DLK1-DIO3 imprinted region to HCC cells, subsequently inhibiting HHIP expression. HHIP is a potential prognostic biomarker in HCC.

Abstract B025: ASCL1 and SOX2 expression levels predict sensitivity to LSD1 inhibition with iadademstat in small cell lung cancer

Abstract Lysine Specific Demethylase 1 (LSD1, also known as KDM1A) is a member of the FAD-containing family of lysine demethylases and is generally involved in repressing transcription by specifically removing methyl groups from mono- and di-methylated lysine 4 of histone 3 - epigenetic marks commonly associated with actively transcribed genes. LSD1 over-expression has been associated with disease progression and worse prognosis in several human cancers, and its inhibition has been shown to reduce cancer cell growth, migration and invasion. LSD1 has therefore been recognized as a target of interest for the development of new drugs to treat cancer. Iadademstat (aka ORY-1001), a highly potent and selective LSD1 inhibitor (LSD1i) in clinical development for malignant indications, and other LSD1is, have been reported to be effective for the treatment of small cell lung cancer (SCLC) in in vitro and in vivo models. However, the published data indicate that while certain SCLC are highly sensitive to LSD1 inhibition this sensitivity is not a universal feature of SCLC cells raising the need to develop methods for identifying sensitive SCLC tumors. Herein, we report the identification of the predictive biomarkers ASCL1 and SOX2 for the enrichment of the SCLC population more likely to respond to iadademstat and other LSD1is. Response to LSD1is was evaluated in a broad panel of SCLC cell lines (from viability assay data obtained internally at Oryzon Genomics with iadademstat and from data published elsewhere using other LSD1is). Additionally, analysis of gene expression was performed in this cell line panel using internal and publicly available datasets (Affymetrix, CCLE). This analysis revealed that the transcription factors ASCL1 and SOX2 are more likely to be highly expressed in SCLC cell lines that respond to LSD1 inhibition. Moreover, the mRNA levels of these biomarkers were highly correlated with their protein levels in both SCLC cell lines and in patient-derived xenografts. In particular, immunofluorescence staining of these patient-derived SCLC samples can discriminate different degrees of ASCL1 and SOX2 protein expression levels (none, low, medium, high), which correlate with their mRNA levels determined by RNAseq in the same samples. Moreover, analysis of ASCL1 and SOX2 protein levels analyzed internally by immunofluorescence in 40 SCLC biopsies showed that 58% samples concomitantly expressed medium to high levels of both biomarkers. Taken together, these data suggest that medium to high expression of both ASCL1 and SOX2 define a SCLC population more likely to respond to LSD1 inhibition, and that this population could account for nearly 60% of SCLC cases. Therefore, ASCL1 and SOX2 expression could be used as predictive biomarkers for personalized medicine with iadademstat in SCLC patients and clinical research to validate this hypothesis is warranted. Citation Format: Natalia Sacilotto, Serena Lunardi, Filippo Ciceri, Cristina Mascaro, Tamara Maes, Ana Limon, Douglas V. Faller. ASCL1 and SOX2 expression levels predict sensitivity to LSD1 inhibition with iadademstat in small cell lung cancer. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr B025.

Abstract PR007: Intestinal intraepithelial T cells limit colorectal cancer progression

Abstract Homeostasis in the gut is achieved by impeccable functioning of tissue resident immune cells that reside and closely interact with the epithelium. The tissue resident immune cells of the intestinal epithelium are predominantly lymphocytes, known as intraepithelial lymphocytes (IELs) and mainly consist of TCRαβ T cells and TCRgd T cells. These IELs are well known to sense microbes, nutrients, and cellular stress but their role in intestinal cancer progression has been controversial. On one hand, gd Τ cells are the primary source of IL-17, an important proinflammatory cytokine that aid in colorectal cancer (CRC) progression. On the other hand, mice lacking gd Τ cells have been showed to have an increased risk of developing carcinogen-induced CRC. Here we used two different mouse model of colon cancer to investigate the role of gd T IELs in colon tumor growth. We showed that in both orthotopic implantation of cancer cells in the colon, and inflammation-driven colon cancer models, gd T cells are essentials to limit tumor growth. Indeed, mice lacking gd T cells had increased tumor incidence with high-grade adenomas compared to control mice. We also performed gene expression analysis of the adenomas in control mice and in mice lacking gd T cells. They revealed distinct transcription profiles with CRC-associated gene expression profile, including inflammatory genes and epithelial to mesenchymal transition genes, particularly enriched in adenomas from gd T cell deficient mice. Moreover, using human tissue microarrays, we investigated whether the presence of gd T cells in tumors of patients with advanced CRC could be used to predict disease outcomes. We revealed that patient disease-free survival was improved if gd T cells could be detected within tumors. Therefore, we showed that gd T cells are primordial in limiting colorectal cancer progression in both mice and humans. Citation Format: Sonia Ghilas, Dinesh Raghu, Kelly Tran, Yang Liao, Bhupinder Pal, Shoukat Sterle, Christine Dijkstra, Marina Yakou, Pavitha Parathan, John Mariadason, Matthias Ernst, Andreas Behren, Grant Drummond, Wei Shi, Lisa A. Mielke. Intestinal intraepithelial T cells limit colorectal cancer progression [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr PR007.

Abstract B008: UBXN2A targets Rictor-mTORC2 signaling pathway to inhibit colorectal cancer metastasis

Abstract The mTORC2 pathway plays a critical role in promoting tumor progression in human colorectal cancer (CRC). The regulatory mechanisms for this signaling pathway are only partially understood in CRC. We previously identified UBXN2A as a novel tumor suppressor protein in CRCs and hypothesized that UBXN2A suppresses the mTORC2 pathway, thereby inhibiting CRC growth and metastasis. We first used murine models to show that haploinsufficiency of UBXN2A significantly increases colon tumorigenesis. Induction of UBXN2A reduces AKT phosphorylation downstream of the mTORC2 pathway, which is essential for a plethora of cellular processes, including cell migration. Meanwhile, mTORC1 activities remain unchanged in the presence of UBXN2A. Mechanistic studies revealed that UBXN2A targets Rictor protein, a key component of the mTORC2 complex, for 26S proteasomal degradation. A set of genetic and pharmacological studies showed that UBXN2A regulates cell proliferation, apoptosis, migration, and colon cancer stem cells (CSCs) in CRC. CRC patients with a high level of UBXN2A have significantly better survival, and high-grade CRC tissues exhibit decreased UBXN2A protein expression. UBXN2A induction in tumor organoids suppresses the mTORC2 pathway. These findings provide new insights into the functions of a ubiquitin-like protein by inhibiting a dominant oncogenic pathway in CRC. Citation Format: Khosrow S. Rezvani. UBXN2A targets Rictor-mTORC2 signaling pathway to inhibit colorectal cancer metastasis [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr B008.

Long Intergenic Non-Protein Coding RNA 173 in Human Cancers

Long non-coding RNAs belong to non-coding RNAs (ncRNAs) with a length of more than 200 nucleotides and limited protein-coding ability. Growing research has clarified that dysregulated lncRNAs are correlated with the development of various complex diseases, including cancer. LINC00173 has drawn researchers' attention as one of the recently discovered lncRNAs. Aberrant expression of LINC00173 affects the initiation and progression of human cancers. In the present review, we summarize the recent considerable research on LINC00173 in 11 human cancers. Through the summary of the abnormal expression of LINC00173 and its potential molecular regulation mechanism in cancers, this article indicates that LINC00173 may serve as a potential diagnostic biomarker and a target for drug therapy, thus providing novel clues for future related research.

Ser815 Phosphorylation stabilizes the androgen receptor homodimer and stimulates ER-stress induced cell death

Androgen receptor, which regulates diverse biological processes for cell fate decisions, forms a homodimer in the cytoplasm and is monomerized by activation for nuclear translocation. Ser815 phosphorylated AR is expressed in mature prostates, with levels decreased by castration in mice or prostate cancer progression in humans. Here, we have examined the functional and biological roles of phosphorylation. AR phosphorylation at Ser815 stabilized homodimer formation in the cytoplasm, interrupting DHT-response nuclear translocation. cDNA microarray studies in castrated mouse prostates implied castration attenuates ER stress responses, suggesting AR phosphorylation acts on ER stress responses. In addition, AR Ser815Asp phospho-mimetic mutant expression augmented ER stress-induced death in PC-3 cells. These results suggested that phosphorylation at AR Ser815 modulates AR functions for maintaining the prostate.

MicroRNA-Gene Interactions Impacted by Toxic Metal(oid)s during EMT and Carcinogenesis.

Chronic environmental exposure to toxic metal(loid)s significantly contributes to human cancer development and progression. It is estimated that approximately 90% of cancer deaths are a result of metastasis of malignant cells, which is initiated by epithelial-mesenchymal transition (EMT) during early carcinogenesis. EMT is regulated by many families of genes and microRNAs (miRNAs) that control signaling pathways for cell survival, death, and/or differentiation. Recent mechanistic studies have shown that toxic metal(loid)s alter the expression of miRNAs responsible for regulating the expression of genes involved in EMT. Altered miRNA expressions have the potential to be biomarkers for predicting survival and responses to treatment in cancers. Significantly, miRNAs can be developed as therapeutic targets for cancer patients in the clinic. In this mini review, we summarize key findings from recent studies that highlight chemical-miRNA-gene interactions leading to the perturbation of EMT after exposure to toxic metal(loid)s including arsenic, cadmium, nickel, and chromium.