Loss of the m6A methyltransferase METTL3 in monocyte-derived macrophages ameliorates Alzheimer's disease pathology in mice.

Alzheimer's disease (AD) is a heterogeneous disease with complex clinicopathological characteristics. To date, the role of m6A RNA methylation in monocyte-derived macrophages involved in the progression of AD is unknown. In our study, we found that methyltransferase-like 3 (METTL3) deficiency in monocyte-derived macrophages improved cognitive function in an amyloid beta (Aß)-induced AD mouse model. The mechanistic study showed that that METTL3 ablation attenuated the m6A modification in DNA methyltransferase 3A (Dnmt3a) mRNAs and consequently impaired YTH N6-methyladenosine RNA binding protein 1 (YTHDF1)-mediated translation of DNMT3A. We identified that DNMT3A bound to the promoter region of alpha-tubulin acetyltransferase 1 (Atat1) and maintained its expression. METTL3 depletion resulted in the down-regulation of ATAT1, reduced acetylation of α-tubulin and subsequently enhanced migration of monocyte-derived macrophages and Aß clearance, which led to the alleviated symptoms of AD. Collectively, our findings demonstrate that m6A methylation could be a promising target for the treatment of AD in the future.

Anti-EGFR ScFv functionalized exosomes delivering LPCAT1 specific siRNAs for inhibition of lung cancer brain metastases.

Brain metastasis (BM) is one of the leading causes of cancer-related deaths in patients with advanced non-small cell lung cancer (NSCLC). However, limited treatments are available due to the presence of the blood-brain barrier (BBB). Upregulation of lysophosphatidylcholine acyltransferase 1 (LPCAT1) in NSCLC has been found to promote BM. Conversely, downregulating LPCAT1 significantly suppresses the proliferation and metastasis of lung cancer cells. In this study, we firstly confirmed significant upregulation of LPCAT1 in BM sites compared to primary lung cancer by analyzing scRNA dataset. We then designed a delivery system based on a single-chain variable fragment (scFv) targeting the epidermal growth factor receptor (EGFR) and exosomes derived from HEK293T cells to enhance cell-targeting capabilities and increase permeability. Next, we loaded LPCAT1 siRNA (siLPCAT1) into these engineered exosomes (exoscFv). This novel scFv-mounted exosome successfully crossed the BBB in an animal model and delivered siLPCAT1 to the BM site. Silencing LPCAT1 efficiently arrested tumor growth and inhibited malignant progression of BM in vivo without detectable toxicity. Overall, we provided a potential platform based on exosomes for RNA interference (RNAi) therapy in lung cancer BM.

LINC00330/CCL2 axis-mediated ESCC TAM reprogramming affects tumor progression.

BACKGROUND: Tumor-associated macrophages (TAMs) significantly influence the progression, metastasis, and recurrence of esophageal squamous cell carcinoma (ESCC). The aberrant expression of long noncoding RNAs (lncRNAs) in ESCC has been established, yet the role of lncRNAs in TAM reprogramming during ESCC progression remains largely unexplored. METHODS: ESCC TAM-related lncRNAs were identified by intersecting differentially expressed lncRNAs with immune-related lncRNAs and performing immune cell infiltration analysis. The expression profile and clinical relevance of LINC00330 were examined using the TCGA database and clinical samples. The LINC00330 overexpression and interference sequences were constructed to evaluate the effect of LINC00330 on ESCC progression. Single-cell sequencing data, CIBERSORTx, and GEPIA were utilized to analyze immune cell infiltration within the ESCC tumor microenvironment and to assess the correlation between LINC00330 and TAM infiltration. ESCC-macrophage coculture experiments were conducted to investigate the influence of LINC00330 on TAM reprogramming and its subsequent effect on ESCC progression. The interaction between LINC00330 and C-C motif ligand 2 (CCL2) was confirmed through transcriptomic sequencing, subcellular localization analysis, RNA pulldown, silver staining, RNA immunoprecipitation, and other experiments. RESULTS: LINC00330 is significantly downregulated in ESCC tissues and strongly associated with poor patient outcomes. Overexpression of LINC00330 inhibits ESCC progression, including proliferation, invasion, epithelial-mesenchymal transition, and tumorigenicity in vivo. LINC00330 promotes TAM reprogramming, and LINC00330-mediated TAM reprogramming inhibits ESCC progression. LINC00330 binds to the CCL2 protein and inhibits the expression of CCL2 and downstream signaling pathways. CCL2 is critical for LINC00330-mediated TAM reprogramming and ESCC progression. CONCLUSIONS: LINC00330 inhibited ESCC progression by disrupting the CCL2/CCR2 axis and its downstream signaling pathways in an autocrine fashion; and by impeding CCL2-mediated TAM reprogramming in a paracrine manner. The new mechanism of TAM reprogramming mediated by the LINC00330/CCL2 axis may provide potential strategies for targeted and immunocombination therapies for patients with ESCC.

Efficient Delivery of GSDMD-N mRNA by Engineered Extracellular Vesicles Induces Pyroptosis for Enhanced Immunotherapy.

Pyroptosis is a newly discovered inflammatory form of programmed cell death, which promotes systemic immune response in cancer immunotherapy. GSDMD is one of the key molecules executing pyroptosis, while therapeutical delivery of GSDMD to tumor cells is of great challenge. In this study, an extracellular vesicles-based GSDMD-N mRNA delivery system (namely EVTx ) is developed for enhanced cancer immunotherapy, with GSDMD-N mRNA encapsulated inside, Ce6 (Chlorin e6 (Ce6), a hydrophilic sensitizer) incorporated into extracellular vesicular membrane, and HER2 antibody displayed onto the surface. Briefly, GSDMD-N mRNA is translationally repressed in donor cells by optimized puromycin, ensuring the cell viability and facilitating the mRNA encapsulation into extracellular vesicles. When targeted and delivered into HER2+ breast cancer cells by the engineered extracellular vesicles, the translational repression is unleashed in the recipient cells as the puromycin is diluted and additionally inactivated by sonodynamic treatment as the extracellular vesicles are armed with Ce6, allowing GSDMD-N translation and pyroptosis induction. In addition, sonodynamic treatment also induces cell death in the recipient cells. In the SKBR3- and HER2 transfected 4T1- inoculated breast tumor mouse models, the engineered EVTx efficiently induces a powerful tumor immune response and suppressed tumor growth, providing a nanoplatform for cancer immunotherapy.

M1 polarization enhances the antitumor activity of chimeric antigen receptor macrophages in solid tumors.

BACKGROUND: Chimeric antigen receptor macrophage (CAR-M) therapy is a novel cancer immunotherapy approach that integrates CAR structure and macrophage functions. CAR-M therapy has shown unique and impressive antitumor effects in immunotherapy for solid tumors. However, the polarization state of macrophages can affect the antitumor effect of CAR-M. We hypothesized that the antitumor activity of CAR-Ms may be further improved after inducing M1-type polarization. METHODS: In this report, we constructed a novel HER2-targeting CAR-M, which was composed of humanized anti-HER2 scFv, CD28 hinge region and FcγRI transmembrane domain and intracellular domain. Phagocytosis, tumor-killing capacities, and cytokine release of CAR-Ms were detected with or without M1-polarization pretreatment. Several syngeneic tumor models were used to monitor the in vivo antitumor activity of M1-polarized CAR-Ms. RESULTS: After polarization with LPS combined with interferon-γ in vitro, we found that the phagocytic and tumor-killing capacities of CAR-Ms against target cells were significantly enhanced. The expression of costimulatory molecules and proinflammatory cytokines was also significantly increased after polarization. By establishing several syngeneic tumor models in vivo, we also demonstrated that infusing polarized M1-type CAR-Ms could effectively suppress tumor progression and prolong the survival of tumor-bearing mice with enhanced cytotoxicity. CONCLUSIONS: We demonstrated that our novel CAR-M can effectively eliminate HER2-positive tumor cells both in vitro and in vivo, and M1 polarization significantly enhanced the antitumor ability of CAR-M, resulting in a stronger therapeutic effect in solid cancer immunotherapy.

Antibody-drug conjugates targeting CD248+ myofibroblasts effectively alleviate renal fibrosis in mice.

Myofibroblasts, or activated fibroblasts, play a critical role in the process of renal fibrosis. Targeting myofibroblasts to inhibit their activation or induce specific cell death has been considered to be an effective strategy to attenuate renal fibrosis. However, specific biomarkers for myofibroblasts are needed to ensure the efficacy of these strategies. Here, we verified that CD248 was mainly expressed in myofibroblasts in patients with chronic kidney disease, which was inversely correlated with renal function. The same result was also confirmed in renal fibrotic mice induced by unilateral ureteral obstruction and aristolochic acid nephropathy. By using an antibody-drug conjugate (ADC) named IgG78-DM1, in which maytansinoid (DM1) was linked to a fully human antibody IgG78 through an uncleavable SMCC linker, we demonstrated that it could effectively bind with and kill CD248+ fibroblasts in vitro and alleviate renal fibrosis in mice models. Besides, we confirmed that IgG78-DM1 had qualified biosafety in vivo. Our results confirmed that CD248 can be used as a specific marker for myofibroblasts, and specific killing of CD248+ myofibroblasts by IgG78-DM1 has excellent anti-fibrotic effect in renal fibrotic mice. Our study expanded the application of ADC and provided a novel strategy for the treatment of renal fibrosis.

Antibody-drug conjugates targeting CD248 inhibits liver fibrosis through specific killing on myofibroblasts.

BACKGROUND: Chronic liver injury induces pathological repair, resulting in fibrosis, during which hepatic stellate cells (HSCs) are activated and transform into myofibroblasts. CD248 is mainly expressed on myofibroblasts and was considered as a promising target to treat fibrosis. The primary aim of this study was to generate a CD248 specific antibody-drug conjugate (ADC) and evaluate its therapeutic efficacy for liver fibrosis and its safety in vivo. METHODS: CD248 expression was examined in patients with liver cirrhosis and in mice with CCl4-induced liver fibrosis. The ADC IgG78-DM1, which targets CD248, was prepared and its bioactivity on activated primary HSCs was studied. The anti-fibrotic effects of IgG78-DM1 on liver fibrosis were evaluated in CCl4-induced mice. The reproductive safety and biosafety of IgG78-DM1 were also evaluated in vivo. RESULTS: CD248 expression was upregulated in patients with liver cirrhosis and in CCl4-induced mice, and was mainly expressed on alpha smooth muscle actin (α-SMA)+ myofibroblasts. IgG78-DM1 was successfully generated, which could effectively bind with and kill CD248+ activated HSCs in vitro and inhibit liver fibrosis in vivo. In addition, IgG78-DM1 was demonstrated to have qualified biosafety and reproductive safety in vivo. CONCLUSIONS: Our study demonstrated that CD248 could be an ideal target for myofibroblasts in liver fibrosis, and CD248-targeting IgG78-DM1 had excellent anti-fibrotic effects in mice with liver fibrosis. Our study provided a novel strategy to treat liver fibrosis and expanded the application of ADCs beyond tumors.

A miR-205-LPCAT1 axis contributes to proliferation and progression in multiple cancers.

In the past two decades, miRNAs have been demonstrated to play critical roles in development and progression of malignant diseases. To identify the role and mechanism of miRNA are urgent for the application of miRNA-based therapeutics in cancers. MiR-205 is a conserved miRNA from the invertebrate to mammalian species. Previous studies showed a large body of evidence to demonstrate the oncogenic or tumor suppressive role of it in different types of cancers. Our aim here is to clarify the role and novel mechanism of miR-205 in solid tumors. In the present study, we found that a high level of miR-205 is an independent biomarker for favorable prognosis in LIHC, HNSCC and LUSC. In the functional experiment, we stably expressed miR-205 in tumor cell lines derived from above mentioned cancers. The result showed that overexpression of miR-205 significantly inhibits cancer cell proliferation. Mechanistically, we identified that the lysophosphatidylcholine acyltransferase-1 (LPCAT1) is a novel target of miR-205 in multiple cancer cells. Furthermore, we found that LPCAT1 is required for sustained proliferation of cancer cells and a high level of it is closely associated with poor prognosis in clinical patients. Collectively, we revealed the important prognostic value of a miR-205-LPCAT1 axis in multiple cancers and highlighted an essential role of LPCAT1 in miR-205-regulated cancer cell proliferation. All these discoveries make a miR-205-LPCAT1 axis to shed light upon a potential therapeutic target in cancer treatment.

WWP2 regulates proliferation of gastric cancer cells in a PTEN-dependent manner.

WW domain containing E3 Ub-protein ligase 2 (WWP2) plays an important role in tumor progression as an E3 ligase of PTEN. Here, we investigated the role of WWP2 in gastric cancer (GC). We found that WWP2 is overexpressed in GC tissues, which is closely related to poor prognosis of GC patients. Using a WWP2-shRNA lentivirus expressing system, we established WWP2 stable-knockdown GC cell lines and found that knockdown of WWP2 inhibits the proliferation of GC cells both in vitro and in vivo. Also, WWP2 silencing induced the up-regulation of PTEN protein level and down-regulation of AKT phosphorylation level. We further investigated the role of PTEN in this regulating process by performing rescue assay and found that PTEN is essential for WWP2-mediated regulation of GC cells proliferation. Taken together, our results demonstrated that WWP2 promotes proliferation of GC cells by downregulating PTEN, which may provide new therapeutic targets for GC.

Wnt4 negatively regulates the TGF-ß1-induced human dermal fibroblast-to-myofibroblast transition via targeting Smad3 and ERK.

Abnormal activation of Wnt signaling has been demonstrated in the wound healing process and the pathogenesis of fibrotic disorders, with Wnt4 specifically identified as having a key role in the pathogenesis of renal, pulmonary and liver fibrosis. Wnt4 also was found to be upregulated by transforming growth factor-ß1 (TGF-ß1) in fetal and postnatal murine fibroblasts and bone marrow mesenchymal cells, suggesting an underlying cooperation between Wnt4 and TGF-ß1 in fibrosis. However, the specific roles of Wnt4 in TGF-ß1-induced skin myofibroblast transition and hypertrophic scar formation remain unclear. In the present study, we first observed reduced Wnt4 expression in hypertrophic scar tissue compared with that in normal skin tissue. Following upregulation by TGF-ß1, Wnt4 inhibited the TGF-ß1-induced transdifferentiation of fibroblasts into myofibroblasts. Using fibroblast-populated collagen lattice contraction assays, we showed that the increased contractility induced by TGF-ß1 was significantly blocked by exogenous Wnt4 and the α-smooth muscle actin (α-SMA) expression was decreased in fibroblasts in the collagen lattices. In addition, knockdown of Wnt4 resulted in further increases in α-SMA and collagen I expressions. Further investigation showed that Wnt4 could inhibit the autocrine effect of TGF-ß1 as well as block the phosphorylation of Smad3 and ERK but not of AKT or JNK. Lastly, using hypertrophic scar-derived fibroblasts, we showed that the elevated α-SMA and collagen I levels were markedly reduced after treatment with Wnt4. Taken together, our results suggest that Wnt4 negatively regulates TGF-ß1-induced fibroblast activation, which may represent a novel therapeutic strategy for the treatment and prevention of hypertrophic scars.

Keratinocyte exosomes activate neutrophils and enhance skin inflammation in psoriasis.

Psoriasis is a chronic inflammatory skin disease that severely affects patients physiologically and psychologically. The pathogenesis involving communication between psoriatic keratinocytes and infiltrated immune cells such as neutrophils remains unclear. Exosomes are emerging mediators of intercellular communication. Herein we aim to investigate the release and function of psoriatic keratinocyte exosomes, which have not been illustrated to any extent. We first isolated exosomes from both healthy and psoriasis-like keratinocytes treated with psoriatic cytokine cocktail. These exosomes were observed to be endocytosed by neutrophils. Unlike non-cytokine-treated keratinocyte exosomes, cytokine-treated keratinocyte exosomes significantly induced NETosis (the process by which neutrophils produce and release neutrophil extracellular traps) and the expressions of IL-6, IL-8, and TNF-α in neutrophils. Proteomic analysis showed that cytokine-treated keratinocyte exosomes exhibited a specific protein profile with proteins enriched in immune-related pathways. We then confirmed that NF-κB and p38 MAPK signaling pathways were activated in neutrophils stimulated by cytokine-treated keratinocyte exosomes and were responsible for the expressions of proinflammatory factors mentioned above. Finally, we verified in vivo that cytokine-treated keratinocyte exosomes participated in the skin lesion development of imiquimod-induced psoriasis-like mouse model. Collectively, we reveal that the release of exosomes works as a way of keratinocyte-neutrophil communication, indicating that keratinocyte exosomes, with their specific cargoes, are therapeutic candidates for psoriasis.-Jiang, M., Fang, H., Shao, S., Dang, E., Zhang, J., Qiao, P., Yang, A., Wang, G. Keratinocyte exosomes activate neutrophils and enhance skin inflammation in psoriasis.

Sp1-mediated epigenetic dysregulation dictates HDAC inhibitor susceptibility of HER2-overexpressing breast cancer.

Human epidermal growth factor receptor 2 (HER2/erbB2) is a key driver and therapeutic target for breast cancer. The treatment of HER2-positive breast cancer remains a clinical challenge largely due to the limited understanding of HER2-driving oncogenic signaling and the frequent resistance to simply HER2-targeted therapy. Here, we show that the histone deacetylase inhibitor, trichostatin A (TSA), suppresses HER2-overexpressing breast cancer via upregulation of miR-146a and the resultant repression of its oncogenic targets, interleukin-1 receptor-associated kinase 1 and the chemokine receptor CXCR4. Mechanistically, histone H3K56 acetylation and deacetylation on the MIR146A promoter are catalyzed respectively by the acetyltransferase p300 and histone deacetylase 1 (HDAC1), both of which are recruited to the genomic loci by the transcription factor specificity protein 1 (Sp1). HER2 signaling phosphorylates Sp1 and induces its predominant association with HDAC1, but not p300, leading to histone hypoacetylation and silencing of MIR146A. In addition, the death receptor Fas is similarly downregulated by the aforementioned epigenetic paradigm, indicating its wide involvement in impairing tumor suppressor gene expression. Consequently, TSA synergizes with lapatinib, a tyrosine kinase inhibitor of HER2, to suppress breast cancer in vitro and in rodent models. These findings demonstrate a novel mechanism of HER2-driven carcinogenesis and suggest the applicability of combined HER2 and HDAC targeting in breast cancer therapy.

Ctrp4, a new adipokine, promotes the differentiation of osteoblasts.

Recent evidence suggests that adipokines are involved in the regulation of bone metabolism. Ctrp4 is a newly discovered member of the adipokine CTRP family. Studies have shown that Ctrp4 is involved in the regulation of tumor cell inflammatory signaling pathways and acts on the hypothalamus to regulate food intake, but its role in osteoblasts is not yet clear. In this study, we found that the expression of Ctrp4 in bone tissue was significantly decreased in the tail-suspended mouse, while that in ovariectomized-simulated osteoporosis mice decreased similarly, indicating that Ctrp4 was involved in osteogenesis regulation. We further isolated Alp-positive osteoblasts from the femur of tail-suspended rats and confirmed that the expression of Ctrp4, Bglap and Alp was down-regulated in the process of bone loss caused by tail suspension. In the process of inducing osteoblastic differentiation in vitro, Ctrp4 interfering significantly inhibited the expression of Alp and Bglap. In addition, inhibition of Ctrp4 resulted in decreased alkaline phosphatase expression and less alizarin red staining, indicating that Ctrp4 promoted osteogenic differentiation and osteoblasts mineralization. In conclusion, our results suggest that Ctrp4 is involved in bone metabolism regulation and promotes osteoblast differentiation, which may become a potential target for future intervention in bone metabolic diseases.

Identification of miRNA-7 by genome-wide analysis as a critical sensitizer for TRAIL-induced apoptosis in glioblastoma cells.

Glioblastoma (GBM) is still one of the most lethal forms of brain tumor despite of the improvements in treatments. TRAIL (TNF-related apoptosis-inducing ligand) is a promising anticancer agent that can be potentially used as an alternative or complementary therapy because of its specific antitumor activity. To define the novel pathways that regulate susceptibility to TRAIL in GBM cells, we performed a genome-wide expression profiling of microRNAs in GBM cell lines with the distinct sensitivity to TRAIL-induced apoptosis. We found that the expression pattern of miR-7 is closely correlated with sensitivity of GBM cells to TRAIL. Furthermore, our gain and loss of function experiments showed that miR-7 is a potential sensitizer for TRAIL-induced apoptosis in GBM cells. In the mechanistic study, we identified XIAP is a direct downstream gene of miR-7. Additionally, this regulatory axis could also exert in other types of tumor cells like hepatocellular carcinoma cells. More importantly, in the xenograft model, enforced expression of miR-7 in TRAIL-overexpressed mesenchymal stem cells increased apoptosis and suppressed tumor growth in an exosome dependent manner. In conclusion, we identify that miR-7 is a critical sensitizer for TRAIL-induced apoptosis, thus making it as a promising therapeutic candidate for TRAIL resistance in GBM cells.

Retraction Note: Nuclear factor of activated T cells 5 maintained by Hotair suppression of miR-568 upregulates S100 calcium binding protein A4 to promote breast cancer metastasis.

The authors are retracting this article [1] after an investigation by the Ethics Committee of the Fourth Military Medical University (Xi'an, Shaanxi, China) of the following concerns that had been raised with respect to two of the figures.

Tumor-suppressive miR-145 co-repressed by TCF4-ß-catenin and PRC2 complexes forms double-negative regulation loops with its negative regulators in colorectal cancer.

The frequently dysregulated Wnt/ß-catenin signaling in different malignancies, by activation of its own or orchestration with other co-factors, regulates various oncogenic or tumor-suppressive genes. Among these genes, miRNAs, which are negative posttranscriptional regulators, are also embedded in the Wnt signaling network. Different from the Wnt-induced oncogenic miRNAs, the specific mechanism underlying the Wnt-repressed tumor-suppressive miRNAs is much less understood. In our study, firstly by analyzing a ChIP-seq dataset against TCF4, the core transcription factor for initiation of Wnt signaling in colorectal cancer (CRC) cells, we screened out several tumor-suppressive miRNAs potentially regulated by Wnt signaling. Then through siRNA-mediated knock-down tests and protein and chromatin immunoprecipitations, we found the TCF4-ß-catenin complex can recruit the histone trimethylation complex PRC2 as a co-repressor while binding to the TCF4-binding element (TBE) in the promoter regions of miR-145, miR-132 and miR-212. Thus, upon Wnt signaling activation, the PRC2-mediated trimethylation of histone H3 at lysine 27 increases at these promoter regions, leading to decreased miRNA levels. Furthermore, we found that by targeting TCF4 and SUZ12, the key components of the negative regulation complexes, the tumor-suppressive miR-145 co-repressed by Wnt signaling and histone trimethylation, forms double-negative regulation loops with its negative regulators in CRC cells. And the inverse associations between miR-145 and its targets/negative regulators have also been demonstrated in nude mice and clinical samples. Collectively, we elucidated the detailed molecular mechanism of how dysregulated Wnt/ß-catenin signaling and tumor-suppressive miRNAs reciprocally regulate each other in CRC cells.

Long non-coding RNA UCA1 desensitizes breast cancer cells to trastuzumab by impeding miR-18a repression of Yes-associated protein 1.

Breast cancer resistance to the monoclonal erbB2/HER2 antibody trastuzumab (or herceptin) has become a significant obstacle in clinical targeted therapy of HER2-positive breast cancer. Previous research demonstrated that such drug resistance may be related to dysregulation of miRNA expression. Here, we found that knockdown of the long non-coding RNA, urothelial cancer associated 1 (UCA1), can promote the sensitivity of human breast cancer cells to trastuzumab. Mechanistically, UCA1 knockdown upregulated miR-18a and promoted miR-18a repression of Yes-associated protein 1 (YAP1). A luciferase reporter assay confirmed the association of miR-18a with wild-type UCA1 but not with UCA1 mutated at the predicted miR-18a-binding site. The direct targeting of YAP1 by miR-18a was verified by the observation that miR-18a mimic suppressed luciferase expression from a construct containing the YAP1 3' untranslated region. Meanwhile, reciprocal repression of UCA1 and miR-18a were found to be Argonaute 2-dependent. Knockdown of YAP1 recapitulated the effect of UCA1 silencing by reducing the viability of trastuzumab-treated breast cancer cells, whereas inhibition of miR-18a abrogated UCA1 knockdown-induced improvement of trastuzumab sensitivity in breast cancer cells. These findings demonstrate that the UCA1/miR-18a/YAP1 axis plays an important role in regulating the sensitivity of breast cancer cells to trastuzumab, which has implications for the development of novel approaches to improving breast cancer responses to targeted therapy.

A miR-124/ITGA3 axis contributes to colorectal cancer metastasis by regulating anoikis susceptibility.

Metastasis is the major cause for the death of patients with colorectal cancer (CRC). Anoikis resistance enhances the survival of cancer cells during systemic circulation, thereby facilitating secondary tumor formation in distant organs. miR-124 is a pleiotropically tumor suppressive small non-coding molecule. However, its role and mechanism in the regulation of cancer cell anoikis are still unknown. Here, we found that overexpression of miR-124 promotes anoikis of CRC cells in vitro and in vivo. In silico analysis and the experimental evidence supported that ITGA3 is a bona fide target of miR-124. Moreover, we identifies that ITGA3 plays a critical role in the regulation of anoikis sensitivity in CRC cells. Finally, our analysis in TCGA datasets demonstrates that high levels of ITGA3 are closely associated with poor prognosis in CRC patients. Collectively, we establish a functional link between miR-124 and anoikis susceptibility and provide that a miR-124/ITGA3 axis could be a potential target for the treatment of metastatic CRC.

FOXM1 promotes proliferation in human hepatocellular carcinoma cells by transcriptional activation of CCNB1.

The transcription factor Forkhead box protein M1 (FOXM1) plays critical roles in cancer development and progression, including human hepatocellular carcinoma (HCC). However, the regulatory role and underlying mechanisms of FOXM1 is still limited. Here, we found that the high level expression of FOXM1 and CCNB1 is closely associated with poor prognosis in HCC patients. And FOXM1 and CCNB1 were overexpressed concomitantly in liver tumor tissues. Knockdown of FOXM1 significantly inhibited the expression levels of CCNB1 in HCC cell lines at both the mRNA and protein levels. Mechanistic studies revealed that FOXM1 binds directly to the promoter region of CCNB1 and regulates the expression levels of the CCNB1 gene in the transcriptional level. Furthermore, the loss of functional and rescue experiments showed that CCNB1 is essential for FOXM1-driven proliferation in HCC cells. In the present study, our results partially explained the dysregulated expression of FOXM1 play an important role in proliferation of human hepatocellular carcinoma cells via transcriptional activation of CCNB1 expression. And it also highlights a FOXM1/CCNB1 axis could be a potential target for the treatment of HCCs.

Targeting and suppression of HER3-positive breast cancer by T lymphocytes expressing a heregulin chimeric antigen receptor.

Chimeric antigen receptor-modulated T lymphocytes (CAR-T) have emerged as a powerful tool for arousing anticancer immunity. Endogenous ligands for tumor antigen may outperform single-chain variable fragments to serve as a component of CARs with high cancer recognition efficacy and minimized immunogenicity. As heterodimerization and signaling partners for human epidermal growth factor receptor 2 (HER2), HER3/HER4 has been implicated in tumorigenic signaling and therapeutic resistance of breast cancer. In this study, we engineered T cells with a CAR consisting of the extracellular domain of heregulin-1ß (HRG1ß) that is a natural ligand for HER3/HER4, and evaluated the specific cytotoxicity of these CAR-T cells in cultured HER3 positive breast cancer cells and xenograft tumors. Our results showed that HRG1ß-CAR was successfully constructed, and T cells were transduced at a rate of 50%. The CAR-T cells specifically recognized and killed HER3-overexpressing breast cancer cells SK-BR-3 and BT-474 in vitro, and displayed potent tumoricidal effect on SK-BR-3 xenograft tumor models. Our results suggest that HRG1ß-based CAR-T cells effectively suppress breast cancer driven by HER family receptors, and may provide a novel strategy to overcome cancer resistance to HER2-targeted therapy.