Immunotherapeutic IL-6R and targeting the MCT-1/IL-6/CXCL7/PD-L1 circuit prevent relapse and metastasis of triple-negative breast cancer.

Rationale: Multiple copies in T-cell malignancy 1 (MCT-1) is a prognostic biomarker for aggressive breast cancers. Overexpressed MCT-1 stimulates the IL-6/IL-6R/gp130/STAT3 axis, which promotes epithelial-to-mesenchymal transition and cancer stemness. Because cancer stemness largely contributes to the tumor metastasis and recurrence, we aimed to identify whether the blockade of MCT-1 and IL-6R can render these effects and to understand the underlying mechanisms that govern the process. Methods: We assessed primary tumor invasion, postsurgical local recurrence and distant metastasis in orthotopic syngeneic mice given the indicated immunotherapy and MCT-1 silencing (shMCT-1). Results: We found that shMCT-1 suppresses the transcriptomes of the inflammatory response and metastatic signaling in TNBC cells and inhibits tumor recurrence, metastasis and mortality in xenograft mice. IL-6R immunotherapy and shMCT-1 combined further decreased intratumoral M2 macrophages and T regulatory cells (Tregs) and avoided postsurgical TNBC expansion. shMCT-1 also enhances IL-6R-based immunotherapy effectively in preventing postsurgical TNBC metastasis, recurrence and mortality. Anti-IL-6R improved helper T, cytotoxic T and natural killer (NK) cells in the lymphatic system and decreased Tregs in the recurrent and metastatic tumors. Combined IL-6R and PD-L1 immunotherapies abridged TNBC cell stemness and M2 macrophage activity to a greater extent than monotherapy. Sequential immunotherapy of PD-L1 and IL-6R demonstrated the best survival outcome and lowest postoperative recurrence and metastasis compared with synchronized therapy, particularly in the shMCT-1 context. Multiple positive feedforward loops of the MCT-1/IL-6/IL-6R/CXCL7/PD-L1 axis were identified in TNBC cells, which boosted metastatic niches and immunosuppressive microenvironments. Clinically, MCT-1high/PD-L1high/CXCL7high and CXCL7high/IL-6high/IL-6Rhigh expression patterns predict worse prognosis and poorer survival of breast cancer patients. Conclusion: Systemic targeting the MCT-1/IL-6/IL-6R/CXCL7/PD-L1 interconnections enhances immune surveillance that inhibits the aggressiveness of TNBC.

Somatic A-to-I RNA-edited RHOA isoform 2 specific-R176G mutation promotes tumor progression in lung adenocarcinoma.

Adenosine-to-inosine (A-to-I) RNA editing is the most common posttranscriptional editing to create somatic mutations and increase proteomic diversity. However, the functions of the edited mutations are largely underexplored. To identify novel targets in lung adenocarcinoma (LUAD), we conducted a genome-wide somatic A-to-I RNA editing analysis of 23 paired adjacent normal and LUAD transcriptomes and identified 26,280 events, including known nonsynonymous AZIN1-S367G and novel RHOAiso2 (RHOA isoform 2)-R176G, tubulin gamma complex associated protein 2 (TUBGCP2)-N211S, and RBMXL1-I40 M mutations. We validated the edited mutations in silico in multiple databases and in newly collected LUAD tissue pairs with the SEQUENOM MassARRAY® and TaqMan PCR Systems. We selected RHOAiso2-R176G due to its significant level, isoform-specificity, and being the most common somatic edited nonsynonymous mutation of RHOAiso2 to investigate its roles in LUAD tumorigenesis. RHOAiso2 is a ubiquitous but low-expression alternative spliced isoform received a unique Alu-rich exon at the 3' RHOA mRNA to become an editing RNA target, leading to somatic hypermutation and protein diversity. Interestingly, LUAD patients harboring the RHOAiso2-R176G mutation were associated with aberrant RHOA functions, cancer cell proliferation and migration, and poor clinical outcomes in transcriptome analysis. Mechanistically, RHOAiso2-R176G mutation-expressing LUAD cells potentiate RHOA-guanosine triphosphate (GTP) activity to phosphorylate ROCK1/2 effectors and enhance cell proliferation and migration in vitro and increase tumor growth in xenograft and systemic metastasis models in vivo. Taken together, the RHOAiso2-R176G mutation is a common somatic A-to-I edited mutation of the hypermutated RHOA isoform 2. It is an oncogenic and isoform-specific theranostic target that activates RHOA-GTP/p-ROCK1/2 signaling to promote tumor progression.

Long noncoding RNA Smyca coactivates TGF-ß/Smad and Myc pathways to drive tumor progression.

BACKGROUND: Metastasis and chemoresistance are major culprits of cancer mortality, but factors contributing to these processes are incompletely understood. METHODS: Bioinformatics methods were used to identify the relations of Smyca expression to clinicopathological features of human cancers. RNA-sequencing analysis was used to reveal Smyca-regulated transcriptome. RNA pull-down and RNA immunoprecipitation were used to examine the binding of Smyca to Smad3/4 and c-Myc/Max. Chromatin immunoprecipitation and chromatin isolation by RNA purification were used to determine the binding of transcription factors and Smyca to various gene loci, respectively. Real-time RT-PCR and luciferase assay were used to examine gene expression levels and promoter activities, respectively. Xenograft mouse models were performed to evaluate the effects of Smyca on metastasis and chemoresistance. Nanoparticle-assisted gapmer antisense oligonucleotides delivery was used to target Smyca in vivo. RESULTS: We identify lncRNA Smyca for its association with poor prognosis of many cancer types. Smyca potentiates metabolic reprogramming, migration, invasion, cancer stemness, metastasis and chemoresistance. Mechanistically, Smyca enhances TGF-ß/Smad signaling by acting as a scaffold for promoting Smad3/Smad4 association and further serves as a Smad target to amplify/prolong TGF-ß signaling. Additionally, Smyca potentiates c-Myc-mediated transcription by enhancing the recruitment of c-Myc/Max complex to a set of target promoters and c-Myc binding to TRRAP. Through potentiating TGF-ß and c-Myc pathways, Smyca synergizes the Warburg effect elicited by both pathways but evades the anti-proliferative effect of TGF-ß. Targeting Smyca prevents metastasis and overcomes chemoresistance. CONCLUSIONS: This study uncovers a lncRNA that coordinates tumor-relevant pathways to orchestra a pro-tumor program and establishes the clinical values of Smyca in cancer prognosis and therapy.

Early prediction of 1-year tumor response of hepatocellular carcinoma with lipiodol deposition pattern through post-embolization cone-beam computed tomography during conventional transarterial chemoembolization.

OBJECTIVE: To evaluate whether parenchyma-to-lipiodol ratio (PLR) and lesion-to-lipiodol ratio (LLR) on C-arm cone-beam computed tomography (CBCT) can predict 1-year tumor response in patients with hepatocellular carcinoma (HCC) treated with conventional transcatheter arterial chemoembolization (cTACE). METHODS: This retrospective analysis included 221 HCC target lesions within up-to-seven criteria in 80 patients who underwent cTACE with arterial-phase CBCT and unenhanced CBCT after cTACE from 2015 to 2018. PLR and LLR of every tumor slice were obtained through mean density division of liver parenchyma and tumor enhancement with intratumoral lipiodol deposition. The cutoff values (COVs) of maximal PLR and LLR of every tumor were analyzed using Youden's index. The reliability of COV, correlations between the related parameters, and 1-year progression were assessed through interobserver agreement and multivariate analysis. COV validity was verified using the chi-square test and Cramer's V coefficient (V) in the validation cohort. RESULTS: Standard COVs of PLR and LLR were 0.149 and 1.4872, respectively. Interobserver agreement of COV for PLR and LLR was near perfect (kappa > 0.9). Multivariate analysis suggested that COV of PLR is an independent predictor (odds ratio = 1.23532×1014, p = 4.37×10-7). COV of PLR showed strong consistency, correlation with 1-year progression in prediction model (V = 0.829-0.776; p < 0.0001), and presented as an effective predictor in the validation cohort (V = 0.766; p < 0.0001). CONCLUSION: The COV of PLR (0.149) assessed through immediate post-embolization CBCT is an objective, effective, and approachable predictor of 1-year HCC progression after cTACE. KEY POINTS: • The maximal PLR value indicates the least lipiodol-distributed region in an HCC tumor. The maximal LLR value indicates the least lipiodol-deposited region in the tumor due to incomplete lipiodol delivery. PLR and LLR are concepts like signal-to-noise ratio to characterize the lipiodol retention pattern objectively to predict 1-year tumor progression immediately without any quantification software for 3D image analysis immediately after cTACE treatment. • COV of PLR can facilitate the early prediction of tumor progression/recurrence and indicate the section of embolized HCC, providing the operator's good targets for sequential cTACE or combined ablation. • The validation cohort in our study verified standard COVs of PLR and LLR. The validation process was more convincing and delicate than that of previous retrospective studies.

Usp11 controls cortical neurogenesis and neuronal migration through Sox11 stabilization.

The role of protein stabilization in cortical development remains poorly understood. A recessive mutation in the USP11 gene is found in a rare neurodevelopmental disorder with intellectual disability, but its pathogenicity and molecular mechanism are unknown. Here, we show that mouse Usp11 is expressed highly in embryonic cerebral cortex, and Usp11 deficiency impairs layer 6 neuron production, delays late-born neuronal migration, and disturbs cognition and anxiety behaviors. Mechanistically, these functions are mediated by a previously unidentified Usp11 substrate, Sox11. Usp11 ablation compromises Sox11 protein accumulation in the developing cortex, despite the induction of Sox11 mRNA. The disease-associated Usp11 mutant fails to stabilize Sox11 and is unable to support cortical neurogenesis and neuronal migration. Our findings define a critical function of Usp11 in cortical development and highlight the importance of orchestrating protein stabilization mechanisms into transcription regulatory programs for a robust induction of cell fate determinants during early brain development.

Integrative analyses of noncoding RNAs reveal the potential mechanisms augmenting tumor malignancy in lung adenocarcinoma.

Precise noncoding RNA (ncRNA)-based network prediction is necessary to reveal ncRNA functions and pathological mechanisms. Here, we established a systemic pipeline to identify prognostic ncRNAs, predict their functions and explore their pathological mechanisms in lung adenocarcinoma (LUAD). After in silico and experimental validation based on evaluations of prognostic value in multiple LUAD cohorts, we selected the PTTG3P pseudogene from among other prognostic ncRNAs (MIR497HG, HSP078, TBX5-AS1, LOC100506990 and C14orf64) for mechanistic studies. PTTG3P upregulation in LUAD cells shortens the metaphase to anaphase transition in mitosis, increases cell viability after cisplatin or paclitaxel treatment, facilitates tumor growth that leads to poor survival in orthotopic lung models, and is associated with a poor survival rate in LUAD patients in the TCGA cohort who received chemotherapy. Mechanistically, PTTG3P acts as an ncRNA that interacts with the transcription factor FOXM1 to regulate the transcriptional activation of the mitotic checkpoint kinase BUB1B, which augments tumor growth and chemoresistance and leads to poor outcomes for LUAD patients. Overall, we established a systematic strategy to uncover prognostic ncRNAs with functional prediction methods suitable for pan-cancer studies. Moreover, we revealed that PTTG3P, due to its upregulation of the PTTG3P/FOXM1/BUB1B axis, could be a therapeutic target for LUAD patients.

PSPC1-interchanged interactions with PTK6 and ß-catenin synergize oncogenic subcellular translocations and tumor progression.

Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide due to metastasis. Paraspeckle component 1 (PSPC1) upregulation has been identified as an HCC pro-metastatic activator associated with poor patient prognosis, but with a lack of targeting strategy. Here, we report that PSPC1, a nuclear substrate of PTK6, sequesters PTK6 in the nucleus and loses its metastasis driving capability. Conversely, PSPC1 upregulation or PSPC1-Y523F mutation promotes epithelial-mesenchymal transition, stemness, and metastasis via cytoplasmic translocation of active PTK6 and nuclear translocation of ß-catenin, which interacts with PSPC1 to augment Wnt3a autocrine signaling. The aberrant nucleocytoplasmic shuttling of active PTK6/ß-catenin is reversed by expressing the PSPC1 C-terminal interacting domain (PSPC1-CT131), thereby suppressing PSPC1/PTK6/ß-catenin-activated metastasis to prolong the survival of HCC orthotopic mice. Thus, PSPC1 is the contextual determinant of the oncogenic switch of PTK6/ß-catenin subcellular localizations, and PSPC1-CT131 functions as a dual inhibitor of PSPC1 and PTK6 with potential for improving cancer therapy.

PSPC1 mediates TGF-ß1 autocrine signalling and Smad2/3 target switching to promote EMT, stemness and metastasis.

Activation of metastatic reprogramming is critical for tumour metastasis. However, more detailed knowledge of the underlying mechanism is needed to enable targeted intervention. Here, we show that paraspeckle component 1 (PSPC1), identified in an aberrant 13q12.11 locus, is upregulated and associated with poor survival in patients with cancer. PSPC1 promotes tumorigenesis, epithelial-to-mesenchymal transition (EMT), stemness and metastasis in multiple cell types and in spontaneous mouse cancer models. PSPC1 is the master activator for transcription factors of EMT and stemness and accompanies c-Myc activation to facilitate tumour growth. PSPC1 increases transforming growth factor-ß1 (TGF-ß1) secretion through an interaction with phosphorylated and nuclear Smad2/3 to potentiate TGF-ß1 autocrine signalling. Moreover, PSPC1 acts as a contextual determinant of the TGF-ß1 pro-metastatic switch to alter Smad2/3 binding preference from tumour-suppressor to pro-metastatic genes. Having validated the PSPC1-Smads-TGF-ß1 axis in various cancers, we conclude that PSPC1 is a master activator of pro-metastatic switches and a potential target for anti-metastasis drugs.

Target genes discovery through copy number alteration analysis in human hepatocellular carcinoma.

High-throughput short-read sequencing of exomes and whole cancer genomes in multiple human hepatocellular carcinoma (HCC) cohorts confirmed previously identified frequently mutated somatic genes, such as TP53, CTNNB1 and AXIN1, and identified several novel genes with moderate mutation frequencies, including ARID1A, ARID2, MLL, MLL2, MLL3, MLL4, IRF2, ATM, CDKN2A, FGF19, PIK3CA, RPS6KA3, JAK1, KEAP1, NFE2L2, C16orf62, LEPR, RAC2, and IL6ST. Functional classification of these mutated genes suggested that alterations in pathways participating in chromatin remodeling, Wnt/ß-catenin signaling, JAK/STAT signaling, and oxidative stress play critical roles in HCC tumorigenesis. Nevertheless, because there are few druggable genes used in HCC therapy, the identification of new therapeutic targets through integrated genomic approaches remains an important task. Because a large amount of HCC genomic data genotyped by high density single nucleotide polymorphism arrays is deposited in the public domain, copy number alteration (CNA) analyses of these arrays is a cost-effective way to reveal target genes through profiling of recurrent and overlapping amplicons, homozygous deletions and potentially unbalanced chromosomal translocations accumulated during HCC progression. Moreover, integration of CNAs with other high-throughput genomic data, such as aberrantly coding transcriptomes and non-coding gene expression in human HCC tissues and rodent HCC models, provides lines of evidence that can be used to facilitate the identification of novel HCC target genes with the potential of improving the survival of HCC patients.