Tumor-associated Gene Expression Research Articles

3D bioprinting of an in vitro hepatoma microenvironment model: Establishment, evaluation, and anticancer drug testing

Tumor behavior, including its response to treatments, is influenced by interactions between mesenchymal and malignant cells, as well as their spatial arrangement. To study tumor biology and evaluate anticancer drugs, accurate 3D tumor models are essential. Here, we developed an in vitro biomimetic hepatoma microenvironment model by combining an extracellular matrix (3DM-7721). Initially, the internal grid structure, composed of 10/6 % GelMA/gelatin loaded with SMMC-7721 cells, was printed using 3D bioprinting. The external component consisted of fibroblasts and human umbilical vein endothelial cells loaded with 10/3 % GelMA/gelatin. A control model (3DP-7721) lacked external cell loading. GelMA/gelatin hydrogels provided robust structural support and biocompatibility. The SMMC-7721 cells in the 3DM-7721 model exhibit superior tumor-associated gene expression and proliferation characteristics when compared to the 3DP-7721 model. Furthermore, the 3DM-7721 type exhibited increased resistance to anticancer agents. SMMC-7721 cells in the 3DM-7721 model exhibit significant tumorigenicity in nude mice. The 3DM-7721 model group showed pathological characteristics of malignant tumors, with a high degree of deterioration, and a significant positive correlation between malignant tumor-related gene pathways. This high-fidelity 3DM-7721 tumor microenvironment model is invaluable for studying tumor progression, devising effective treatment strategies, and discovering drugs. Statement of significance1.A hepatoma microenvironment model (3DM-7721) incorporating an extracellular matrix that is designed to establish solid tumor models in vitro.2.This model contains a 3D-printed internal tumor component of liver cancer cells loaded with 10/6 % gelatin methacrylate (GelMA)/gelatin (the 3DP-7721 model) and an external extracellular-matrix component of fibroblasts and human umbilical vein endothelial cells loaded with 10/3 % GelMA/gelatin.3.The 3DM-7721 model outperforms the 3DP-7721 model in terms of the SMMC-7721 cell proliferation characteristics and tumorigenicity, tumor-related gene expression, anticancer drug resistance, and malignant tumor characteristics.

Spatial transcriptomics of B cell and T cell receptors reveals lymphocyte clonal dynamics.

The spatial distribution of lymphocyte clones within tissues is critical to their development, selection, and expansion. We have developed spatial transcriptomics of variable, diversity, and joining (VDJ) sequences (Spatial VDJ), a method that maps B cell and T cell receptor sequences in human tissue sections. Spatial VDJ captures lymphocyte clones that match canonical B and T cell distributions and amplifies clonal sequences confirmed by orthogonal methods. We found spatial congruency between paired receptor chains, developed a computational framework to predict receptor pairs, and linked the expansion of distinct B cell clones to different tumor-associated gene expression programs. Spatial VDJ delineates B cell clonal diversity and lineage trajectories within their anatomical niche. Thus, Spatial VDJ captures lymphocyte spatial clonal architecture across tissues, providing a platform to harness clonal sequences for therapy.

Multiparametric magnetic resonance imaging discerns glioblastoma immune microenvironmental heterogeneity.

Poor clinical outcomes for patients with glioblastoma are in part due to dysfunction of the tumor-immune microenvironment. An imaging approach able to characterize immune microenvironmental signatures could provide a framework for biologically based patient stratification and response assessment. We hypothesized spatially distinct gene expression networks can be distinguished by multiparametric Magnetic Resonance Imaging (MRI) phenotypes. Patients with newly diagnosed glioblastoma underwent image-guided tissue sampling allowing for co-registration of MRI metrics with gene expression profiles. MRI phenotypes based on gadolinium contrast enhancing lesion (CEL) and non-enhancing lesion (NCEL) regions were subdivided based on imaging parameters (relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC)). Gene set enrichment analysis and immune cell type abundance was estimated using CIBERSORT methodology. Significance thresholds were set at a p-value cutoff 0.005 and an FDR q-value cutoff of 0.1. Thirteen patients (eight men, five women, mean age 58 ± 11years) provided 30 tissue samples (16 CEL and 14 NCEL). Six non-neoplastic gliosis samples differentiated astrocyte repair from tumor associated gene expression. MRI phenotypes displayed extensive transcriptional variance reflecting biological networks, including multiple immune pathways. CEL regions demonstrated higher immunologic signature expression than NCEL, while NCEL regions demonstrated stronger immune signature expression levels than gliotic non-tumor brain. Incorporation of rCBV and ADC metrics identified sample clusters with differing immune microenvironmental signatures. Taken together, our study demonstrates that MRI phenotypes provide an approach for non-invasively characterizing tumoral and immune microenvironmental glioblastoma gene expression networks.

Fecal gene detection based on next generation sequencing for colorectal cancer diagnosis.

BACKGROUNDColorectal cancer (CRC) is one of the most common malignancies worldwide. Given its insidious onset, the condition often already progresses to advanced stage when symptoms occur. Thus, early diagnosis is of great significance for timely clinical intervention, efficacy enhancement, and prognostic improvement. Featuring high throughput, fastness, and rich information, next generation sequencing (NGS) can greatly shorten the detection time, which is a widely used detection technique at present.AIMTo screen specific genes or gene combinations in fecal DNA that are suitable for diagnosis and prognostic prediction of CRC, and to establish a technological platform for CRC screening, diagnosis, and efficacy monitoring through fecal DNA detection. METHODSNGS was used to sequence the stool DNA of patients with CRC, which were then compared with the genetic testing results of the stool samples of normal controls and patients with benign intestinal disease, as well as the tumor tissues of CRC patients. Specific genes or gene combinations in fecal DNA suitable for diagnosis and prognostic prediction of CRC were screened, and their significances in diagnosing CRC and predicting patients' prognosis were comprehensively evaluated. RESULTSHigh mutation frequencies of TP53, APC, and KRAS were detected in the stools and tumor tissues of CRC patients prior to surgery. Contrastively, no pathogenic mutations of the above three genes were noted in the postoperative stools, the normal controls, or the benign intestinal disease group. This indicates that tumor-specific DNA was detectable in the preoperative stools of CRC patients. The preoperative fecal expression of tumor-associated genes can reflect the gene mutations in tumor tissues to some extent. Compared to the postoperative stools and the stools in the two control groups, the pathogenic mutation frequencies of TP53 and KRAS were significantly higher for the preoperative stools (χ2 = 7.328, P < 0.05; χ2 = 4.219, P < 0.05), suggesting that fecal TP53 and KRAS genes can be used for CRC screening, diagnosis, and prognostic prediction. No significant difference in the pathogenic mutation frequency of the APC gene was found from the postoperative stools or the two control groups (χ2 = 0.878, P > 0.05), so further analysis with larger sample size is required. Among CRC patients, the pathogenic mutation sites of TP53 occurred in 16 of 27 preoperative stools, with a true positive rate of 59.26%, while the pathogenic mutation sites of KRAS occurred in 10 stools, with a true positive rate of 37.04%. The sensitivity and negative predictive values of the combined genetic testing of TP53 and KRAS were 66.67% (18/27) and 68.97%, respectively, both of which were higher than those of TP53 or KRAS mutation detection alone, suggesting that the combined genetic testing can improve the CRC detection rate. The mutation sites TP53 exon 4 A84G and EGFR exon 20 I821T (mutation start and stop positions were both 7579436 for the former, while 55249164 for the latter) were found in the preoperative stools and tumor tissues. These "undetected" mutation sites may be new types of mutations occurring during the CRC carcinogenesis and progression, which needs to be confirmed through further research. Some mutations of "unknown clinical significance" were found in such genes as TP53, PTEN, KRAS, BRAF, AKT1, and PIK3CA, whose clinical values is worthy of further exploration.CONCLUSIONNGS-based fecal genetic testing can be used as a complementary technique for the CRC diagnosis. Fecal TP53 and KRAS can be used as specific genes for the screening, diagnosis, prognostic prediction, and recurrence monitoring of CRC. Moreover, the combined testing of TP53 and KRAS genes can improve the CRC detection rate.

Lactate induces aberration in the miR-30a\u2013DBF4 axis to promote the development of gastric cancer and weakens the sensitivity to 5-Fu

BackgroundGastric cancer (GC) is one of the most common malignancies, molecular mechanism of which is still not clear. Aberrant expression of tumor-associated genes is the major cause of tumorigenesis. DBF4 is an important factor in cancers, although there is yet no report on its function and molecular mechanism in GC.MethodsThe expression of DBF4 in tumor tissues or cells of GC was detected by qRT-PCR and western blotting. Gastric cancer cell line MGC-803 and AGS were transfected with DBF4 siRNA or overexpression vector to detect the function of DBF4 in proliferation, migration and the sensitivity to 5-Fu with CCK-8 assay, colony formation assay, transwell assay, and wound healing assay. miR-30a was found to be the regulator of DBF4 by online bioinformatics software and confirmed with qRT-PCR, western blot and dual-luciferase reporter assays.ResultsIn our study, increased expression of DBF4 in GC tissues was first identified through The Cancer Genome Atlas (TCGA) and later confirmed using specimens from GC patients. Furthermore, functional experiments were applied to demonstrate that DBF4 promotes cell proliferation and migration in GC cell lines, moreover weakens the sensitivity of MGC803 and AGS cells to 5-Fu. We further demonstrated that miR-30a showed significantly lower expression in GC cells and inhibited the expression of DBF4 through 3ʹ-UTR suppression. Furthermore, rescue experiments revealed that the miR-30a-DBF4 axis regulated the GC cell proliferation, migration and the sensitivity to 5-Fu. The important composition in tumor microenvironment, lactate, may be the primary factor that suppressed miR-30a to strengthen the expression of DBF4.ConclusionsTaken together, our study was the first to identify DBF4 as a regulator of cell proliferation and migration in GC. Furthermore, our study identified the lactate-miR-30a-DBF4 axis as a crucial regulator of tumor progression and the tumor sensitivity to 5-Fu, which maybe serve useful for the development of novel therapeutic targets.

Upregulation of α enolase (ENO1) crotonylation in colorectal cancer and its promoting effect on cancer cell metastasis

Lysine crotonylation (Kcr) is a newly identified protein translational modification and is involved in major biological processes including glycolysis, but its role in colorectal cancer (CRC) is unknown. Here, we found that the Kcr of α enolase (ENO1) was significantly elevated in human CRC tissues compared with the paratumoral tissues. CREB-binding protein (CBP) functioned as a crotonyltranferase of ENO1, and SIRT2 was involved in the decrotonylation of ENO1. Using quantitative mass spectrometry for crotonylomics analysis, we further found that K420 was the main Kcr site of ENO1 and ENO1 K420 Kcr promoted the growth, migration, and invasion of CRC cells in vitro by enhancing the activity of ENO1 and regulating the expression of tumor-associated genes. Our study reveals an important mechanism by which ENO1 regulates CRC through crotonylation.

A Critical Role of Peptidylprolyl Isomerase A Pseudogene 22/microRNA-197-3p/Peptidylprolyl Isomerase A Axis in Hepatocellular Carcinoma.

The burden of hepatocellular carcinoma (HCC) worldwide is increasing over time, while the underlying molecular mechanism of HCC development is still under exploration. Pseudogenes are classified as a special type of long non-coding RNAs (lncRNAs), and they played a vital role in regulating tumor-associated gene expression. Here, we report that a pseudogene peptidylprolyl isomerase A pseudogene 22 (PPIAP22) and its parental gene peptidylprolyl isomerase A (PPIA) were upregulated in HCC and were associated with the clinical outcomes of HCC. Further investigation revealed that PPIAP22 might upregulate the expression of PPIA through sponging microRNA (miR)-197-3p, behaving as competing endogenous RNA (ceRNA). PPIA could participate in the development of HCC by regulating mRNA metabolic process and tumor immunity based on the functional enrichment analysis. We also found a strong correlation between the expression levels of PPIA and the immune cell infiltration or the expression of chemokines, especially macrophage, C-C motif chemokine ligand 15 (CCL15), and C-X-C motif chemokine ligand 12 (CXCL12). Our findings demonstrate that the PPIAP22/miR-197-3p/PPIA axis plays a vital role in the progression of HCC by increasing the malignancy of tumor cells and regulating the immune cell infiltration, especially macrophage, through CCL15-CCR1 or CXCL12-CXCR4/CXCR7 pathways.

GRB2-associated binding protein 2 regulates multiple pathways associated with the development of prostate cancer.

The development of prostate cancer is complicated and involves a number of tumor-associated gene expression level abnormalities. Gene chip technology is a high-throughput method that can detect gene expression levels in different tissues and cells on a large scale. In the present study, gene chip technology was used to screen differentially expressed genes in PC-3 human prostate cancer cells following GRB-associated binding protein 2 (GAB2) gene knockdown, and the corresponding biological information was analyzed to investigate the role of GAB2 in prostate cancer. The PC-3 human prostate cancer cell GAB2 gene was knocked out and gene chip hybridization and bioinformatics methods were used to analyze the classical pathway and predict upstream regulatory molecules, disease and function associations and genetic interaction networks. According to the screening conditions |fold change|>1 and P<0.05, 1,242 differential genes were screened; 665 genes were upregulated, and 577 genes were downregulated. Ingenuity Pathway Analysis software demonstrated that GAB2 regulates pathways, such as the superpathway of cholesterol biosynthesis and p53 signaling in cells, and serves a role in diseases and functions such as ‘non-melanoma solid tumors’, ‘viral infections’ and ‘morbidity or mortality’. In the occurrence and development of prostate cancer, factors such as the activation of genes involved in the proliferative cycle, abnormalities in metabolism-associated enzyme gene activities and viral infection play key roles. The present study provides novel research directions and therapeutic targets for prostate cancer.

Free Fatty Acids Promote the Development of Prostate Cancer by Upregulating Peroxisome Proliferator-Activated Receptor Gamma.

IntroductionAs one of the most common forms of cancer that threatens men’s health, prostate cancer (PCa) is under a trend of increasing morbidity and mortality in most countries. More and more studies have pointed out that obesity is closely linked to the occurrence and development of PCa, although there are still many undiscovered molecular mechanisms between the two.MethodsIn the present study, we compare serum lipid levels in patients with PCa and normal individuals. PCa cells (PC3 and 22RV1) were cultured in vitro, the TC/TG/HDL/GLU assay kit was used to detect the glucose and lipid metabolism level of PCa cells, the flow cytometry technique was used to detect the proliferation ability of PCa cells, and the Transwell was used to detect the invasion and migration ability of PCa cells. Western blot/quantitative real-time PCR was used to detect peroxisome proliferator-activated receptor γ (PPARγ) and vimentin/vascular endothelial growth factor-A (VEGF-A) expression levels, and immunohistochemistry was used to observe tumor-associated gene expression levels in nude mice. All data were analysed using the Independent samples t-test or rank sum test.ResultsWe found higher levels of FFA in the serum of patients with PCa. In vitro experiments have demonstrated that high levels of FFA can promote the proliferation, migration and invasion of two PCa cells (PC3 and 22RV1) and affect the energy metabolism of PCa cells. The upregulated PPARγ plays a key role in this process, and vimentin may be involved in this signaling pathway.ConclusionWe infer that high levels of FFA may promote PCa development by upregulating PPARγ expression.

Abstract LB-C17: Engineered hydrogel to elucidate contributions of matrix mechanics to esophageal adenocarcinoma and identify matrix-activated therapeutic targets

Abstract Introduction: Changes in the tumor microenvironment arbitrated by a stiffened ECM are associated with tumor aggression and enable increased propensity towards metastasis. For instance, in vitro (2D) studies have implicated ECM properties in EAC progression, suggesting their exploitation for esophageal therapy following surgical resection. However, these studies are limited by the lack of 3D intercellular interactions, underscoring the need for physiologically relevant 3D culture models (e.g., organotypic culture; organoids) that better recapitulate human cancer and its microenvironment to elucidate underlying mechanisms. Engineered hydrogels are an evolving and important component of 3D organoid culture systems, especially to introduce tunable physicochemical matrix signals that have been investigated in tumor progression and metastasis. Furthermore, patient-derived tumor organoids have become an attractive pre-clinical in vitro model to study cancer biology and evaluate response to therapeutics. Methods: Therefore, we have engineered a visible light-mediated stiffening hydrogel platform that supports the development of patient-derived Barrett’s esophagus (BE) organoids, a precursor to esophageal adenocarcinoma (EAC), as well as EAC organoids. This synthetic biomaterial platform allows temporal control over hydrogel stiffness to better recapitulate the mechanically dynamic esophageal cancer microenvironment, and may help identify therapeutic targets in matrix stiffening-exposed EAC organoids. Results: Our preliminary data have demonstrated that BE and EAC organoid growth and epithelial budding of BE organoids can be controlled by synthetic ECM biomechanical properties, demonstrating the significance of understanding the independent contributions of ECM properties to EAC development, which is inherently limited in biologically-derived materials (e.g. MatrigelTM). Furthermore, our data show that the synthetic ECM allows precise control over hydrogel stiffness as a function of visible light exposure time while demonstrating no reduction in cell viability. Future studies involve identifying matrix-activated therapeutic targets by assessing changes in expression of tumor-associated genes (e.g. TP53, EGFR) and mediators of mechanotransduction (e.g. ROCK, YAP1) as a function of matrix stiffening, and identifying differentially expressed genes using high-throughput transcriptome sequencing between stiffened hydrogel-encapsulated BE and EAC organoid conditions. SUMMARY: Our work is significant because it establishes a biomaterial platform that overcomes the limitations of current 3D organoid culture methods to elucidate the role of the tumor microenvironment in EAC tumorigenesis and to identify disease-relevant therapeutic targets. Successful completion of this work will also provide an opportunity to further establish the engineered biomaterial as a platform to potentially elucidate the mechanisms of, and therapy targets for, other human adenocarcinomas in the context of changes in the mechanics of tumor microenvironment. FUNDING: CEET T32-ES019851 and NCI P01-CA098101. Citation Format: Ricardo Cruz-Acuna, Claudia Loebel, Tatiana Karakasheva, Joel Gabre, Jason A Burdick, Anil K Rustgi. Engineered hydrogel to elucidate contributions of matrix mechanics to esophageal adenocarcinoma and identify matrix-activated therapeutic targets [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr LB-C17. doi:10.1158/1535-7163.TARG-19-LB-C17

MRNA expression of tumor-associated genes in canine grade I meningiomas.

This study was undertaken to establish a method for measuring mRNA expression by using real-time RT-PCR in the diagnosis of canine meningiomas. When performing real-time RT-PCR, it is essential to include appropriate control tissues and to select appropriate housekeeping genes as an internal standard. Based on the results of our study, RPS18 constitutes a suitable internal standard for the comparison of mRNA expression between normal meninges and meningiomas. The results showed increased mRNA expression of VEGFA and EGFR; however, mRNA expression of KDR was reduced. Measuring mRNA expression by using real-time RT-PCR with appropriate control tissues and internal standards can provide useful information to understanding the pathogenesis of canine meningiomas, which corresponds with immunohistochemical findings.

Differential expression of tumor-associated genes and altered gut microbiome with decreased Akkermansia muciniphila confer a tumor-preventive microenvironment in intestinal epithelial Pten-deficient mice

Phosphatase and tensin homolog (Pten) antagonizes PI3K-Akt signaling; therefore, Pten impairment causes tumorigenesis. However, the correlation between Pten deficiency and colon cancer has remained elusive due to numerous opposite observations. To study this correlation, we examined whether Pten deficiency in intestinal epithelial cells (IECs) induces tumorigenesis.With mucosal biopsies of human colon cancer and normal colon, Pten mRNA was evaluated by quantitative PCR. Using IEC-specific Pten knockout mice (PtenΔIEC/ΔIEC), we examined the mitotic activity of IECs; and PtenΔIEC/ΔIEC; Apcmin/+ mice were generated by combining PtenΔIEC/ΔIEC with Apcmin/+ mice. Tumor-associated gene was evaluated by micro-array analysis. Fecal microbiome was analyzed through 16S rRNA gene sequencing.We found that Pten mRNA level was reduced in human colon cancer relative to normal tissues. Augmented chromatids, increased Ki-67 and PCNA expression, and enhanced Akt activation were identified in IECs of PtenΔIEC/ΔIEC mice compared to Pten+/+ littermate. Combining PtenΔIEC/ΔIEC with Apcmin/+ condition caused rapid and aggressive intestinal tumorigenesis. However, PtenΔIEC/ΔIEC mice did not develop any tumors. While maintaining the tumor-driving potential, these data indicated that IEC-Pten deficiency alone did not induce tumorigenesis in mice. Furthermore, the expression of tumor-promoting and tumor-suppressing genes was decreased and increased, respectively, in the intestine of PtenΔIEC/ΔIEC mice compared to controls. The abundance of Akkermansia muciniphila, capable of inducing chronic intestinal inflammation, was diminished in PtenΔIEC/ΔIEC mice compared to controls.These findings suggested that altered tumor-associated gene expression and changed gut microbiota shape a tumor-preventive microenvironment to counteract the tumor-driving potential, leading to the tumor prevention in PtenΔIEC/ΔIEC mice.

The histone deacetylases HDAC1 and HDAC2 are required for the growth and survival of renal carcinoma cells.

Novel therapies are required for the treatment of metastatic renal cell carcinoma (RCC), which is associated with inoperable disease and patient death. Histone deacetylases (HDACs) are epigenetic modifiers and potential drug targets. Additional information on molecular pathways that are altered by histone deacetylase inhibitors (HDACi) in RCC cells is warranted. It should equally be delineated further which individual members of the 18 mammalian HDACs determine the survival and tumor-associated gene expression programs of such cells. Most importantly, an ongoing dispute whether HDACi promote or suppress metastasis-associated epithelial-to-mesenchymal transition (EMT) has to be resolved before HDACi are considered further as clinically relevant drugs. Here we show how HDACi affect murine and primary human RCC cells. We find that these agents induce morphological alterations resembling the metastasis-associated EMT. However, individual and proteomics-based analyses of epithelial and mesenchymal marker proteins and of EMT-associated transcription factors (EMT-TFs) reveal that HDACi do not trigger EMT. Pathway deconvolution analysis identifies reduced proliferation and apoptosis induction as key effects of HDACi. Furthermore, these drugs lead to a reduction of the cell adhesion molecule E-cadherin and of the platelet-derived growth factor receptor-β (PDGFRβ), which is a key driver of RCC metastasis formation. Accordingly, HDACi reduce the pulmonary spread of syngeneic transplanted renal carcinoma cells in mice. Specific genetic elimination of the histone deacetylases HDAC1/HDAC2 reflects the effects of pharmacological HDAC inhibition regarding growth suppression, apoptosis, and the downregulation of E-cadherin and PDGFRβ. Thus, these epigenetic modifiers are non-redundant gatekeepers of cell fate and precise pharmacological targets.

Tumor Progression Is Mediated by Thymosin-β4 through a TGFβ/MRTF Signaling Axis.

Although enhanced thymosin β4 (TMSB4X/Tβ4) expression is associated with tumor progression and metastasis, its tumor-promoting functions remain largely unknown. Here, it is demonstrated that TGFβ facilitates Tβ4 expression and leads to the activation of myocardin-related transcription factors (MRTF), which are coactivators of serum response factor (SRF) and regulate the expression of genes critical for the epithelial-mesenchymal transition (EMT) and tumor metastasis. In murine mammary gland cells (NMuMG), Tβ4 upregulation is required for full induction of a MRTF-regulated EMT gene expression program after TGFβ stimulation. Tβ4 levels are transcriptionally regulated via the novel cis-acting element AGACAAAG, which interacts with Smad and T-cell factor/lymphoid enhancer factor (TCF/LEF) to synergistically activate the Tβ4 promoter downstream of TGFβ. Murine skin melanoma cells (B16F0 and B16F1) also show the expression regulation of Tβ4 by Smad and TCF/LEF. Tβ4-knockout B16F1 (Tβ4 KO) clones show significantly diminished expression level of tumor-associated genes, which is regulated by the TGFβ/MRTFs pathway. In multiple human cancers, Tβ4 levels correlate positively with TGFβ1 and the tumor-associated gene expression levels through processes that respectively depend on TGFβ receptor 1 (TGFBR1) and MRTF expression. Kaplan-Meier survival analyses demonstrate that high Tβ4 expression associates with poor prognosis in an SRF expression-dependent manner in several cancers. In mice, Tβ4 KO clones show significantly decreased experimental metastatic potential; furthermore, ectopic expression of constitutively active MRTF-A fully restores the diminished metastatic activity. In conclusion, the TGFβ/Tβ4/MRTF/SRF pathway is critical for metastasis and tumor progression.Implications: These findings define a molecular mechanism underlying a tumor-promoting function of thymosin β4 through activation of MRTF/SRF signaling. Mol Cancer Res; 16(5); 880-93. ©2018 AACR.

Research advances in the association of miRNAs with EGFR mutation, EGFR-TKI, and radiotherapy in non-small cell lung cancer

Epidermal growth factor receptor (EGFR) is most popular in targeted therapy for non-small cell lung cancer (NSCLC). In recent years, there have been a great number of molecular biology studies of EGFR. Radiotherapy is well-known as a traditional and important treatment for NSCLC, and the treatment outcome is associated with EGFR mutation and overexpression. Phase Ⅲ trials are needed to evaluate the effect of a combination of radiotherapy and EGFR-tyrosine kinase inhibitor (EGFR-TKI) in the treatment of NSCLC. MicroRNAs (miRNAs) can modulate tumor-associated gene expression and influence the biological process of tumor. Recent studies have demonstrated that miRNAs play a positive or negative role in EGFR mutation, EGFR-TKI treatment, and radiotherapy, which mechanism has been partially clarified. In this article, we review the research advances in the association of miRNAs with EGFR mutation, EGFR-TKI, and radiotherapy, so as to provide the latest evidence for the application of miRNAs in the combination of radiotherapy and EGFR-TKI for the treatment of NSCLC. Key words: Carcinoma, non-small cell lung/radiotherapy; Epidermal growth factor receptor; Tyrosine kinase inhibitor

Upregulation of Yes-associated protein and transcriptional co-activator with PDZ-binding motif influences the behavior of LOVO human colon adenocarcinoma cells.

The present study aimed to investigate the role of Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) in the LOVO human colon adenocarcinoma cell line and explore the underlying mechanisms. First, the expression levels of YAP and TAZ were detected in LOVO cells using reverse-transcription quantitative PCR, and the results suggested that YAP and TAZ were faintly expressed in LOVO cells. To investigate the exact role of YAP and TAZ in LOVO cells, stable YAP- and/or TAZ-overexpressing LOVO cell lines were established using YAP and/or TAZ expression plasmids. An MTT assay and flow cytometry were used to assess cell proliferation and apoptosis, respectively. The results indicated that compared with the control, YAP or TAZ overexpression significantly increased the proliferation ability of LOVO cells, while apoptosis was significantly decreased. Furthermore, the expression of the tumor-associated proteins connective tissue growth factor and cysteine-rich angiogenic inducer 61, which have critical roles in facilitating cancer cell proliferation, migration and invasion, were found to be upregulated following upregulation of YAP and TAZ. In addition, the expression of cell apoptosis-associated protein B-cell lymphoma 2 (Bcl-2) was significantly increased, while Bcl-2-associated X protein and caspase-3 were inhibited by YAP or TAZ overexpression. All of these effects were amplified when YAP and TAZ were co-overexpressed. In conclusion, YAP and TAZ function as tumor promoters in human colon carcinoma, and upregulation of YAP and TAZ influences the behavior of LOVO colon adenocarcinoma cells via regulating tumor-associated gene expression.

Activation of HERV-K Env protein is essential for tumorigenesis and metastasis of breast cancer cells.

Human endogenous retrovirus type K (HERV-K) Env protein was previously demonstrated to be overexpressed in human breast cancer (BC) cells and tissues. However, the molecular pathways driving the specific alterations are unknown. We now show that knockdown of its expression with an shRNA (shRNAenv) blocked BC cell proliferation, migration, and invasion. shRNAenv transduction also attenuated the ability of BC cells to form tumors, and notably prevented metastasis. Mechanistically, downregulation of HERV-K blocked expression of tumor-associated genes that included Ras, p-RSK, and p-ERK. The major upstream regulators influenced by HERV-K knockdown were p53, TGF- β1, and MYC. Of interest, when the HERV-K env gene was overexpressed in shRNAenv-transduced BC cells using an HERV-K env expression vector, Ras/Raf/MEK/ERK pathway signaling was restored. CDK5, which alters p53 phosphorylation in some cancers, was upregulated and p53 was downregulated when HERV-K was overexpressed. CDK5 is also a mediator of TGF-β1-induced epithelial-mesenchymal transition and migration in cancer cells, and is involved in tumor formation. Importantly, reductions in migration, invasion, and transformation of BC cells stably transduced with shRNAenv was reversed after adding back a vector with a synonymous mutation of HERV-K env. Taken together, these results indicate that HERV-K Env protein plays an important role in tumorigenesis and metastasis of BC.

The role of the cancer stem cell marker USP22 in tumors

Ubiquitin specific peptidase 22 (USP22) is one of the 11 known death-from-cancer signature genes. USP22 is also considered a cancer stem cell marker and is highly expressed in a variety of tumor types. USP22 alters the expression of tumor-associated genes (e.g., proto-oncogenes and tumor suppressor genes) and promotes tumor cell proliferation, invasion and metastasis via the modification of cell cycle activity and the activation of a variety of signaling pathways. In patients with tumors, USP22 expression is related to lymphatic metastasis, clinical stage of tumors, survival rate and a number of other factors. In addition, USP22 is considered an indicator of a poor prognosis and thus may be used to evaluate the prognosis of patients with tumors. As a potential cancer stem cell marker, USP22 may serve as a novel target for tumor therapies. Finally, USP22 also plays an important role in tumor development and progression.

Application of a Clinical Whole-Transcriptome Assay for Staging and Prognosis of Prostate Cancer Diagnosed in Needle Core Biopsy Specimens

Molecular and genomic analysis of microscopic quantities of tumor from formalin-fixed, paraffin-embedded biopsy specimens has many unique challenges. Herein, we evaluated the feasibility of obtaining transcriptome-wide RNA expression to measure prognostic classifiers in diagnostic prostate needle core biopsy specimens. One-hundred fifty-eight samples from diagnostic needle core biopsy specimens (BX) and radical prostatectomies (RPs) were collected from 33 patients at three hospitals; each patient provided up to six tumor and benign samples. Genome-wide transcriptomic profiles were generated using Affymetrix Human Exon arrays for comparison of gene expression alterations and prognostic signatures between the BX and RP samples. A sufficient amount of RNA (>100 ng) was obtained from all RP specimens (n = 77) and from 72 of 81 of BX specimens. Of transcriptomic features detected in RP, 95% were detectable in BX tissues and demonstrated a high correlation (r=0.96). Likewise, an expression signature pattern validated on RPs (Decipher prognostic test) showed correlation between BX and RP (r=0.70). Of matched BX and RP pairs, 25% showed discordant molecular subtypes. Genome-wide exon arrays yielded data of comparable quality from biopsy and RP tissues. The high concordance of tumor-associated gene expression changes between BX and RP samples provides evidence for the adequate performance of the assay platform with samples from prostate needle biopsy specimens with limited tumor volume.

Abstract 1626: Evaluation of the expression of neuroblastoma-associated genes for bone marrow (BM) involvement and minimal residual disease (MRD) detection

Abstract Methods. Panel of 4 tumor-associated genes (TAGs): PHOX2B, TH, ELAVL4 and GD2 was created. Normalized expression (CtABL-CtTAG) of these genes was analyzed in neuroblastoma (NB) cell lines, in 26 BM samples from patients without malignancies, in the discovery (331 BM samples from 57 patients) and validation cohorts of NB patients (311 BM samples from 55 patients) and in 23 peripheral blood stem cells (PBSC) preparations. For performing of ROC analysis BM samples were defined as positive in case of detectable PHOX2B expression or tumor cells presence in BM smears. Threshold levels (TL) of each gene expression were established and subsequently applied for overall correct prediction (OCP) computation. Prognostic significance of the BM positivity for the evaluated markers was determined using event-free (EFS) and overall survival (OS) rates with median of follow-up time 2.45 years. Results. Neither PHOX2B nor TH expression was detected in the intact BM, while expression of ELAVL4 was revealed in 20 and GD2 - in 15 of 26 BM samples of patients without malignancies. In the discovery cohort 105 analyzed BM samples were positive for PHOX2B expression, while 101 for TH. TH expression was revealed in 5 out of 224 negative BM samples. ELAVL4 and GD2 expression was detected in all 107 positive BM samples as well as in the majority of negative BM samples (209 and 197 of 224, respectively). TL of TH, ELAVL4 and GD2 expression established by ROC analysis were -16.535, -7.130 and -8.459. OCP values calculated using TL achieved 0.952, 0.828 and 0.767 correspondingly. OCP for PHOX2B was 0.994. Due to high OCP values for PHOX2B and TH expression of these genes was analyzed in the validation cohort, where TL for TH was -13.995, while OCP values achieved 0.997 for PHOX2B and 0.939 for TH. Presence of PHOX2B/TH expression in BM at the time of primary NB diagnostics led to decreased both EFS (.31SE.12 vs .81SE.06, p&amp;lt;.001) and OS (.31SE.13 vs .87SE.05, p&amp;lt;.001). Persistence of TAGs expression during the treatment demonstrated trend to reduced EFS (.27SE.12 vs .43SE.19, p = .08). No expression of TAGs was find in the PBSC preparations while positivity for PHOX2B/TH expression before PBSC apheresis had strongly negative prognostic impact (EFS .00 vs .35SE.14, p = .04; OS .00 vs .36SE.15, p = .03) despite of CD34+ selection. Predominance of PHOX2B expression over TH in BM of primary NB patients with the difference in normalized expression greater then 1.68 had negative prognostic significance: EFS .00 vs .56SE.12, p = .017, OS .00 vs .72SE.11, p = .006. Conclusion. PHOX2B and TH are the most appropriate markers for BM involvement and MRD detection in NB patients. Presence of these TAGs expression in the BM at the time of primary diagnostics and before PBSC apheresis had strongly negative prognostic impact. Predominance of PHOX2B expression over TH in the BM can define high risk patients. Citation Format: Alexander E. Druy, Egor V. Shorikov, Grigory A. Tsaur, Alexander M. Popov, Leonid I. Saveliev, Larisa G. Fechina. Evaluation of the expression of neuroblastoma-associated genes for bone marrow (BM) involvement and minimal residual disease (MRD) detection. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1626. doi:10.1158/1538-7445.AM2015-1626