Depletion of slow-cycling PDGFRα+ADAM12+ mesenchymal cells promotes antitumor immunity by restricting macrophage efferocytosis.

The capacity to survive and thrive in conditions of limited resources and high inflammation is a major driver of tumor malignancy. Here we identified slow-cycling ADAM12+PDGFRα+ mesenchymal stromal cells (MSCs) induced at the tumor margins in mouse models of melanoma, pancreatic cancer and prostate cancer. Using inducible lineage tracing and transcriptomics, we demonstrated that metabolically altered ADAM12+ MSCs induced pathological angiogenesis and immunosuppression by promoting macrophage efferocytosis and polarization through overexpression of genes such as Gas6, Lgals3 and Csf1. Genetic depletion of ADAM12+ cells restored a functional tumor vasculature, reduced hypoxia and acidosis and normalized CAFs, inducing infiltration of effector T cells and growth inhibition of melanomas and pancreatic neuroendocrine cancer, in a process dependent on TGF-ß. In human cancer, ADAM12 stratifies patients with high levels of hypoxia and innate resistance mechanisms, as well as factors associated with a poor prognosis and drug resistance such as AXL. Altogether, our data show that depletion of tumor-induced slow-cycling PDGFRα+ MSCs through ADAM12 restores antitumor immunity.

Hypoxia-inducible factor-dependent ADAM12 expression mediates breast cancer invasion and metastasis.

Breast cancer patients with increased expression of hypoxia-inducible factors (HIFs) in primary tumor biopsies are at increased risk of metastasis, which is the major cause of breast cancer-related mortality. The mechanisms by which intratumoral hypoxia and HIFs regulate metastasis are not fully elucidated. In this paper, we report that exposure of human breast cancer cells to hypoxia activates epidermal growth factor receptor (EGFR) signaling that is mediated by the HIF-dependent expression of a disintegrin and metalloprotease 12 (ADAM12), which mediates increased ectodomain shedding of heparin-binding EGF-like growth factor, an EGFR ligand, leading to EGFR-dependent phosphorylation of focal adhesion kinase. Inhibition of ADAM12 expression or activity decreased hypoxia-induced breast cancer cell migration and invasion in vitro, and dramatically impaired lung metastasis after orthotopic implantation of MDA-MB-231 human breast cancer cells into the mammary fat pad of immunodeficient mice.

Polymorphism of ADAM12, DPP6 and PRKN genes and their associations with milk production traits in Holstein.

Milk production traits as the most important economic traits of dairy cows, they directly reflect the benefits of breeding and the economic benefits of pasture. In this study, A disintegrin and metalloproteinase-12 (ADAM12), Parkinson's disease gene 2 (PRKN) and dipeptidyl peptidase-like protein subtype 6 (DPP6) polymorphism in 384 Chinese Holstein cows were detected by time-of-flight mass spectrometry and through statistical analysis using software such as Popgene 32, SAS 9.4 and Origin 2022, the relationship between single nucleotide polymorphisms (SNPs) of three genes with four milk production traits such as daily milk yield (DMY), milk fat percentage (MFP), milk protein percentage (MPP) and somatic cell score (SCS) was verified at molecular level. The results showed that four polymorphic loci (116,467,133, 116,604,487, 116,618,268 and 116,835,111) of DPP6 gene, two polymorphic loci (97,665,052 and 97,159,837) of PRKN gene and two polymorphic loci (45,542,714 and 45,553,888) of ADAM12 gene were detected. PRKN-97665052, DPP6-116467133, ADAM12-45553888, DPP6-116604487 and DPP6-116835111 were all in Hardy-Weinberg equilibrium state (p > .05). ADAM12-45542714, PRKN-97159837 and PRKN-97665052 were moderately polymorphic (0.25 ≤ PIC <0.50) in Holstein. It is evident that the selection potential and genetic variation of these five loci are relatively large, and the genetic richness is relatively high. The correlation analysis of different genotypes between these eight loci and milk production traits of Holstein showed that ADAM12-45542714 and DPP6-116835111 (p < .01) had an extremely significant effects on the DMY of Chinese Holstein in Ningxia, while PRKN-97665052 had an extremely significant effect on MFP (p < .01). The effect of PRKN-97665052 and DPP6-116467133 on MPP of Holstein were extremely significant (p < .01). DPP6-116618268 had an extremely significant effect on the SCS of Holstein in Ningxia (p < .01), and AA genotype individuals showed a higher SCS than GG genotype individuals; the other two loci (ADAM12-45553888 and DPP6-116604487) had no significant effects on milk production traits of Holstein (p > .05). In addition, through the joint analysis of DPP6, PRKN and ADAM12 gene loci, it was found that the interaction effect between the three gene loci could significantly affect the DMY, SCS (p < .01) and MPP (p < .05). In conclusion, several different loci of DPP6, PRKN and ADAM12 genes can affect the milk production traits of Holstein to different degrees. PRKN, DPP6 and ADAM12 genes can be used as potential candidate genes for milk production traits of Holstein for marker-assisted selection, providing theoretical basis for breeding of Holstein.

ADAM12-Generated Basigin Ectodomain Binds ß1 Integrin and Enhances the Expression of Cancer-Related Extracellular Matrix Proteins.

Desmoplasia is a common feature of aggressive cancers, driven by a complex interplay of protein production and degradation. Basigin is a type 1 integral membrane receptor secreted in exosomes or released by ectodomain shedding from the cell surface. Given that soluble basigin is increased in the circulation of patients with a poor cancer prognosis, we explored the putative role of the ADAM12-generated basigin ectodomain in cancer progression. We show that recombinant basigin ectodomain binds ß1 integrin and stimulates gelatin degradation and the migration of cancer cells in a matrix metalloproteinase (MMP)- and ß1-integrin-dependent manner. Subsequent in vitro and in vivo experiments demonstrated the altered expression of extracellular matrix proteins, including fibronectin and collagen type 5. Thus, we found increased deposits of collagen type 5 in the stroma of nude mice tumors of the human tumor cell line MCF7 expressing ADAM12-mimicking the desmoplastic response seen in human cancer. Our findings indicate a feedback loop between ADAM12 expression, basigin shedding, TGFß signaling, and extracellular matrix (ECM) remodeling, which could be a mechanism by which ADAM12-generated basigin ectodomain contributes to the regulation of desmoplasia, a key feature in human cancer progression.

ADAM12 promotes clear cell renal cell carcinoma progression and triggers EMT via EGFR/ERK signaling pathway.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a major worldwide health problem due to its high prevalence and mortality rate. A disintegrin and metalloproteinase 12 (ADAM12) is aberrantly expressed in various cancers and plays an important role in tumor progression. However, its explicit effect and molecular mechanism in ccRCC remain unclear. METHODS: We investigated the dysregulation of ADAM12 in ccRCC through public databases and bioinformatics analyses. The expression of ADAM12 was further verified in ccRCC tissues by RT-qPCR and immunohistochemistry (IHC). The relationship between ADAM12 expression and clinicopathological characteristics was analyzed statistically. The effects of ADAM12 on the proliferation, migration and invasion of ccRCC cells were examined by in vitro and in vivo experiments. RESULTS: ADAM12 was significantly upregulated in ccRCC tissues and associated with poor prognosis in ccRCC patients. ADAM12 promoted ccRCC cell proliferation, migration and invasion in vitro and the growth of subcutaneous tumors in vivo. Knockdown of ADAM12 successfully suppressed its oncogenic function. Mechanistically, its overexpression induced epithelial-mesenchymal transition (EMT) by downregulating E-cadherin and upregulating N-cadherin and Snail. Moreover, ADAM12 participated in the epidermal growth factor receptor (EGFR) pathway and activated the downstream signal ERK1/2 by shedding the EGFR ligand, thereby upregulating target genes including c-Myc, enhancing cell survival and invasion ability, and promoting tumor progression, metastasis and the induction of EMT. CONCLUSIONS: High expression of ADAM12 induced EMT and promoted cell proliferation, migration, and invasion by activating the EGFR/ERK signaling pathway in ccRCC.

Proteomics and Biochemical Analyses of Secreted Proteins Revealed a Novel Mechanism by Which ADAM12S Regulates the Migration of Gastric Cancer Cells.

Gastric cancer is one of the cancers with the highest morbidity and mortality. Although several therapeutic approaches have been developed to treat this disease, the overall survival rate is still very low due to metastasis, drug resistance, and so forth. Therefore, it is necessary to discover new regulatory molecules and signaling pathways that modulate the metastasis of gastric cancer cells. A Disintegrin And Metalloprotease 12 (ADAM12) was highly expressed in gastric cancer tissues and presented in the patient urine. However, it is unclear whether and how ADAM12 regulates the migration of gastric cancer cells. In this work, we used the secretome protein enrichment with click sugars (SPECS) method to purify the secreted glycosylated proteins and performed quantitative proteomics to identify the secreted proteins that were differentially regulated by ADAM12S, the short and secreted form of ADAM12. Our proteomic and biochemical analyses revealed that ADAM12S upregulated the cell surface glycoprotein CD146, a cell adhesion molecule and melanoma marker, which was dependent on the catalytic residue of ADAM12S. Furthermore, we discovered that the ADAM12S-enhanced migration of gastric cancer cells was, at least partially, mediated by CD146. This work may help to evaluate whether ADAM12 could be a potential therapeutic target for the treatment of gastric cancer patients.

Role of EZH2-mediated H3K27me3 in placental ADAM12-S expression: implications for fetoplacental growth.

BACKGROUND: Enhancer of zeste homolog 2 (EZH2)-mediated histone 3 lysine 27 trimethylation (H3K27me3) is a transcription silencing mark, which is indispensable for cell lineage specification at the early blastocyst stage. This epigenetic repression is maintained in placental cytotrophoblasts but is lifted when cytotrophoblasts differentiate into syncytiotrophoblasts. However, the physiological impact of this lift remains elusive. Here, we investigated whether lifting EZH2-mediated H3K27me3 during syncytialization upregulates the expression of a short secretory isoform of a disintegrin and metalloprotease 12 (ADAM12-S), a well-recognized placenta-derived protease that cleaves insulin-like growth factor binding protein 3 to increase insulin-like growth factor (IGF) bioavailability for the stimulation of fetoplacental growth. The transcription factor and the upstream signal involved were also explored. METHODS: Human placenta tissue and cultured primary human placental cytotrophoblasts were utilized to investigate the role of EZH2-mediated H3K27me3 in ADAM12-S expression and the associated transcription factor and upstream signal during syncytialization. A mouse model was used to examine whether inhibition of EZH2-mediated H3K27me3 regulates placental ADAM12-S expression and fetoplacental growth. RESULTS: EZH2 and ADAM12 are distributed primarily in villous cytotrophoblasts and syncytiotrophoblasts, respectively. Increased ADAM12-S expression, decreased EZH2 expression, and decreased EZH2/H3K27me3 enrichment at the ADAM12 promoter were observed during syncytialization. Knock-down of EZH2 further increased ADAM12-S expression in trophoblasts. Syncytialization was also accompanied by increased STAT5B expression and phosphorylation as well as its enrichment at the ADAM12 promoter. Knock-down of STAT5B attenuated ADAM12-S expression during syncytialization. Epidermal growth factor (EGF) was capable of inducing ADAM12-S expression via stimulation of STAT5B expression and phosphorylation during syncytialization. Mouse studies revealed that administration of an EZH2 inhibitor significantly increased ADAM12-S levels in maternal blood and fetoplacental weights along with decreased H3K27me3 abundance and increased ADAM12-S expression in the placenta. CONCLUSIONS: Lifting EZH2-mediated H3K27me3 increases ADAM12-S expression during syncytialization with the participation of EGF-activated STAT5B, which may lead to elevation of ADAM12-S level in maternal blood resulting in increased IGF bioavailability for the stimulation of fetoplacental growth in pregnancy. Our studies suggest that the role of EZH2-mediated H3K27me3 may switch from cell lineage specification at the early blastocyst stage to regulation of fetoplacental growth in later gestation.

Serum-based measurements of stromal activation through ADAM12 associate with poor prognosis in colorectal cancer.

BACKGROUND: Recently it has been recognized that stromal markers could be used as a clinically relevant biomarker for therapy response and prognosis. Here, we report on a serum marker for stromal activation, A Disintegrin and Metalloprotease 12 (ADAM12) in colorectal cancer (CRC). METHODS: Using gene expression databases we investigated ADAM12 expression in CRC and delineated the source of ADAM12 expression. The clinical value of ADAM12 was retrospectively assessed in the CAIRO2 trial in metastatic CRC with 235 patients (31% of total cohort), and an independent rectal cancer cohort (n = 20). RESULTS: ADAM12 is expressed by activated CRC associated fibroblasts. In the CAIRO2 trial cohort, ADAM12 serum levels were prognostic (ADAM12 low versus ADAM12 high; median OS 25.3 vs. 17.1 months, HR 1.48 [95% CI 1.11-1.96], P = 0.007). The prognostic potential was specifically high for metastatic rectal cancer (HR 1.78 [95% CI 1.06-3.00], P = 0.030) and mesenchymal subtype tumors (HR 2.12 [95% CI 1.25-3.60], P = 0.004). ADAM12 also showed potential for predicting recurrence in an exploratory analysis of non-metastatic rectal cancers. CONCLUSIONS: Here we describe a non-invasive marker for activated stroma in CRC which associates with poor outcome, especially for primary cancers located in the rectum.

Impact of disintegrin and metalloproteinase domain-containing protein 12 on pancreatic ductal adenocarcinoma treated with surgical resection and perioperative chemotherapy.

BACKGROUND/OBJECTIVES: A disintegrin and metalloproteinase domain-containing protein 12 (ADAM12) has been reported to influence tumor progression and chemosensitivity in human cancers. We assessed the prognostic impact of ADAM12 and its predictive value for neoadjuvant chemotherapy (NAC) in patients with pancreatic ductal adenocarcinoma (PDAC) treated with surgical resection. METHODS: ADAM12 expression was immunohistochemically examined in 428 patients with PDAC who underwent surgical resection. The association of ADAM12 expression with clinicopathological factors and survival was also analyzed. RESULTS: Patients with high ADAM12 expression exhibited significantly shorter median disease-free survival (DFS) (high ADAM12: 17.8 vs. low ADAM12: 37.9 months; P < 0.001) and overall survival (OS) (high ADAM12: 33.1 vs. low ADAM12: 65.0 months; P < 0.001). A multivariate analysis revealed that high ADAM12 expression was an independent risk factor for poor DFS (P < 0.001) and OS (P < 0.001) in all eligible patients. Of 100 patients who received neoadjuvant chemotherapy (NAC), high ADAM12 expression was significantly associated with poor DFS in a subset of patients treated with the nab-paclitaxel (PTX) neoadjuvant regimen (P = 0.03), whereas the prognostic value of ADAM12 was not evident in patients not treated with nab-PTX (P = 0.12). CONCLUSIONS: A negative prognostic value of high ADAM12 expression was observed in patients with PDAC treated with surgical resection, which was enhanced in patients treated with NAC, including nab-PTX. These results suggested that ADAM12 expression can predict nab-PTX chemosensitivity in PDAC and reflect PDAC progression.

Tetra-primers ARMS-PCR Based Association Analyses of Synonymous and Intronic Variants in the ADAM12 Gene with Susceptibility to Knee Osteoarthritis: A Case-Control Study.

Genetic variations in a disintegrin and metalloprotease 12 (ADAM12) gene may contribute to develop Osteoarthritis (OA) that is characterized by cartilage matrix degradation and osteophytes formation. Therefore, the aim of present study was to analyze the association between the ADAM12 gene variants and knee OA predisposition. Tetra-primers ARMS-PCR was employed, to genotype the ADAM12 gene polymorphisms (rs1044122 and rs1871054) in 400 knee OA patients and equal number of age-matched controls. The association between ADAM12 gene variants and OA susceptibility was estimated using the Chi-square, logistic regression, haplotypes and linkage analyses. A significant association of rs1044122 (genotype: χ2 = 18.94; P < 0.001, allele: χ2 = 19.10; P < 0.001) and rs1871054 (genotype: χ2 = 10.04; P = 0.007, allele: χ2 = 10.57; P = 0.001) was observed with increased OA susceptibility. The variant genotype of rs1044122 increased OA risk more than twice [odds ratio (OR) 2.20; P = 0.001] and the risk was higher in females (OR 2.43; P = 0.001). The variant genotype of rs1871054 was perceived to almost double the risk in females (OR 1.97; P = 0.003). Moreover, a significant association of rs1044122 and rs1871054 under the additive genetic model (P < 0.001 and P = 0.002, respectively) was observed. The targeted ADAM12 gene polymorphisms, showed significant association with knee OA susceptibility. Females harboring the polymorphisms might be at risk. Besides, the haplotype CC of rs1044122 and rs1871054 in the ADAM12 gene may double knee OA risk. These findings may help in determining the etiology of OA and recognizing the people at risk of developing knee OA.

The role of cell surface proteins gene expression in diagnosis, prognosis, and drug resistance of colorectal cancer: In silico analysis and validation.

Cell surface proteins (CSPs) are an important type of protein in different essential cell functions. This study aimed to distinguish overexpressed CSPs in colorectal cancer to investigate their biomarker, prognosis, and drug resistance potential. Raw data of three datasets including 1187 samples was downloaded then normalization and differential expression were performed. By the combination of the cancer genome atlas (TCGA) clinical data, survival analysis was carried out. Information of all CSPs was collected from cell surface protein atlas. The role of each candidate gene expression was investigated in drug resistance by CCEL and GDSC data from PharmacoGX. CRC samples including 30 tumor samples and adjacent normal were used to confirm data by RT-qPCR. Outcomes showed that 66 CSPs overexpressed in three datasets, and 146 CSPs expression associated with poor prognosis features in TCGA data that TIMP1 and QSOX2 can associate with poor patient survival independently. High-risk patients illustrated more fatality than low-risk patients based on the risk score calculated by the expression level of these genes. Receiver operating characteristic curve analysis showed that 39 CSPs as perfect biomarkers for diagnosis in CRC. Furthermore, QSOX2 and TIMP1 expression levels increased in tumor samples compared to adjacent normal samples. The Drug resistance analysis demonstrated ADAM12 and COL1A2 up-regulation among 66 overexpressed CSPs caused resistance to Venetoclax and Cyclophosphamide with a high estimate, respectively. Many CSPs are deregulated in CRC, and can be valuable candidates as biomarkers for diagnosis, prognosis, and drug resistance.

Increased ADAM12 Expression Predicts Poor Prognosis in Cervical Cancer Patients before General Anesthesia.

BACKGROUND: The current study aims to investigate the expression and diagnostic value of ADAM12 in patients with cervical cancer before general anesthesia. METHODS: Seventy-eight cases of cervical cancer patients were included in the present study. RT-PCR and western blot were used to detect the expression of ADAM12 in cervical cancer tissues and adjacent tissues. Meanwhile, the expression of secretory ADAM12 in serum of cervical cancer patients and healthy people was detected by ELISA. The relationship between ADAM12 expression and prognosis of cervical cancer patients was analyzed. ROC analysis was carried out to explore the diagnostic value of ADAM12. RESULTS: Our data showed that the expression of ADAM12 mRNA and protein in cervical cancer tissues was significantly up-regulated compared with the adjacent tissues. ELISA assay showed that the content of ADAM12 in serum of cervical cancer patients was significantly higher than that of healthy people. Furthermore, ADAM12 expression was closely related to tumor invasion, TNM stage, lymph node metastasis and tumor differentiation. Kaplan-Meier survival analysis showed that the overall survival rate of patients with high ADAM12 was significantly lower than that of patients with low ADAM12 expression. The AUC of ADAM12, CEA, CA125, and SCC for cervical cancer was 0.893, 0.510, 0.769 and 0.550, respectively, while the highest value of AUC was 0.946 by the combination of the four indexes. CONCLUSIONS: In summary, increased expression of ADAM12 in cervical cancer patients can be used as an independent prognostic marker.

Genetic screens reveal mechanisms for the transcriptional regulation of tissue-specific genes in normal cells and tumors.

The proper tissue-specific regulation of gene expression is essential for development and homeostasis in metazoans. However, the illegitimate expression of normally tissue-restricted genes-like testis- or placenta-specific genes-is frequently observed in tumors; this promotes transformation, but also allows immunotherapy. Two important questions are: how is the expression of these genes controlled in healthy cells? And how is this altered in cancer? To address these questions, we used an unbiased approach to test the ability of 350 distinct genetic or epigenetic perturbations to induce the illegitimate expression of over 40 tissue-restricted genes in primary human cells. We find that almost all of these genes are remarkably resistant to reactivation by a single alteration in signaling pathways or chromatin regulation. However, a few genes differ and are more readily activated; one is the placenta-expressed gene ADAM12, which promotes invasion. Using cellular systems, an animal model, and bioinformatics, we find that a non-canonical but druggable TGF-ß/KAT2A/TAK1 axis controls ADAM12 induction in normal and cancer cells. More broadly, our data show that illegitimate gene expression in cancer is an heterogeneous phenomenon, with a few genes activatable by simple events, and most genes likely requiring a combination of events to become reactivated.

Genetic and developmental origins of a unique foraging adaptation in a Lake Malawi cichlid genus.

Phenotypic novelties are an important but poorly understood category of morphological diversity. They can provide insights into the origins of phenotypic variation, but we know relatively little about their genetic origins. Cichlid fishes display remarkable diversity in craniofacial anatomy, including several novelties. One aspect of this variation is a conspicuous, exaggerated snout that has evolved in a single Malawi cichlid lineage and is associated with foraging specialization and increased ecological success. We examined the developmental and genetic origins for this phenotype and found that the snout is composed of two hypertrophied tissues: the intermaxillary ligament (IML), which connects the right and left sides of the upper jaw, and the overlying loose connective tissue. The IML is present in all cichlids, but in its exaggerated form it interdigitates with the more superficial connective tissue and anchors to the epithelium, forming a unique ligament-epithelial complex. We examined the Transforming growth factor ß (Tgfß) → Scleraxis (Scx) candidate pathway and confirmed a role for these factors in snout development. We demonstrate further that experimental up-regulation of Tgfß is sufficient to produce an expansion of scx expression and concomitant changes in snout morphology. Genetic and genomic mapping show that core members of canonical Tgfß signaling segregate with quantitative trait loci (QTL) for snout variation. These data also implicate a candidate for ligament development, adam12, which we confirm using the zebrafish model. Collectively, these data provide insights into ligament morphogenesis, as well as how an ecologically relevant novelty can arise at the molecular level.

Analysis of ADAM12-Mediated Ephrin-A1 Cleavage and Its Biological Functions.

Accumulating evidence indicates that an elevated ephrin-A1 expression is positively correlated with a worse prognosis in some cancers such as colon and liver cancer. The detailed mechanism of an elevated ephrin-A1 expression in a worse prognosis still remains to be fully elucidated. We previously reported that ADAM12-cleaved ephrin-A1 enhanced lung vascular permeability and thereby induced lung metastasis. However, it is still unclear whether or not cleaved forms of ephrin-A1 are derived from primary tumors and have biological activities. We identified the ADAM12-mediated cleavage site of ephrin-A1 by a Matrix-assisted laser desorption ionization mass spectrometry and checked levels of ephrin-A1 in the serum and the urine derived from the primary tumors by using a mouse model. We found elevated levels of tumor-derived ephrin-A1 in the serum and the urine in the tumor-bearing mice. Moreover, inhibition of ADAM-mediated cleavage of ephrin-A1 or antagonization of the EphA receptors resulted in a significant reduction of lung metastasis. The results suggest that tumor-derived ephrin-A1 is not only a potential biomarker to predict lung metastasis from the primary tumor highly expressing ephrin-A1 but also a therapeutic target of lung metastasis.

Modulation of miR-29a and ADAM12 Reduces Post-Ischemic Skeletal Muscle Injury and Improves Perfusion Recovery and Skeletal Muscle Function in a Mouse Model of Type 2 Diabetes and Peripheral Artery Disease.

Both Type 1 diabetes mellitus (DM1) and type 2 diabetes mellitus (DM2) are associated with an increased risk of limb amputation in peripheral arterial disease (PAD). How diabetes contributes to poor PAD outcomes is poorly understood but may occur through different mechanisms in DM1 and DM2. Previously, we identified a disintegrin and metalloproteinase gene 12 (ADAM12) as a key genetic modifier of post-ischemic perfusion recovery. In an experimental PAD, we showed that ADAM12 is regulated by miR-29a and this regulation is impaired in ischemic endothelial cells in DM1, contributing to poor perfusion recovery. Here we investigated whether miR-29a regulation of ADAM12 is altered in experimental PAD in the setting of DM2. We also explored whether modulation of miR-29a and ADAM12 expression can improve perfusion recovery and limb function in mice with DM2. Our result showed that in the ischemic limb of mice with DM2, miR-29a expression is poorly downregulated and ADAM12 upregulation is impaired. Inhibition of miR-29a and overexpression of ADAM12 improved perfusion recovery, reduced skeletal muscle injury, improved muscle function, and increased cleaved Tie 2 and AKT phosphorylation. Thus, inhibition of miR-29a and or augmentation of ADAM12 improves experimental PAD outcomes in DM2 likely through modulation of Tie 2 and AKT signalling.

Preoperative serum ADAM12 levels as a stromal marker for overall survival and benefit of adjuvant therapy in patients with resected pancreatic and periampullary cancer.

BACKGROUND: We evaluated the stroma marker A Disintegrin And Metalloprotease 12 (ADAM12) as a preoperative prognostic and treatment-predictive marker for overall survival (OS) in pancreatic ductal adenocarcinoma (PDAC) and periampullary cancers. METHODS: Materials were derived from the prospective nationwide Dutch Pancreas Biobank (2015-2017). We included patients who underwent resection because of PDAC/periampullary cancer or non-invasive IPMN (control group) and had a preoperative serum sample available. ADAM12 levels were dichotomized using a pre-defined cut-off (316 pg/mL). Univariable and multivariable Cox regression analyses (backward selection) were performed. RESULTS: Median ADAM12 levels were 161 (IQR 79-352) pg/mL in 215 PDAC and periampullary adenocarcinomas. High ADAM12 levels (>316 pg/mL) predicted poor OS in the total group of pancreatic and periampullary adenocarcinomas (P = 0.04), but not after adjustment. In distal cholangiocarcinoma (n = 33), high ADAM12 levels predicted poor OS in univariable analysis (P = 0.02), but not in PDAC (P = 0.63). PDAC patients (n = 135) with high ADAM12 levels benefited from adjuvant treatment (median OS 27 vs 14 months, P = 0.02), whereas those with low levels did not (21 vs 21 months, P = 0.87). CONCLUSION: High circulating ADAM12 levels, as a proxy for activated stroma, predict survival benefit from adjuvant chemotherapy in PDAC, requiring validation in future studies.

A disintegrin and metalloproteinase 12 prevents heart failure by regulating cardiac hypertrophy and fibrosis.

A disintegrin and metalloproteinase (ADAM)12 is considered to promote cardiac dysfunction based on the finding that a small-molecule ADAM12 inhibitor, KB-R7785, ameliorated cardiac function in a transverse aortic constriction (TAC) model by inhibiting the proteolytic activation of heparin-binding-EGF signaling. However, this compound has poor selectivity for ADAM12, and the role of ADAM12 in cardiac dysfunction has not yet been investigated using genetic loss-of-function mice. We revealed that ADAM12 knockout mice showed significantly more advanced cardiac hypertrophy and higher mortality rates than wild-type mice 4 wk after TAC surgery. An ADAM12 deficiency resulted in significantly more expanded cardiac fibrosis accompanied by increased collagen-related gene expression in failing hearts. The results of a genome-wide transcriptional analysis suggested a strongly enhanced focal adhesion- and fibrosis-related signaling pathway in ADAM12 knockout hearts. The loss of ADAM12 increased the abundance of the integrinß1 subunit and transforming growth factor (TGF)-ß receptor types I and III, and this was followed by the phosphorylation of focal adhesion kinase, Akt, mammalian target of rapamycin, ERK, and Smad2/3 in the heart, which resulted in cardiac dysfunction. The present results revealed that the loss of ADAM12 enhanced focal adhesion and canonical TGF-ß signaling by regulating the abundance of the integrinß1 and TGF-ß receptors.NEW & NOTEWORTHY In contrast to a long-believed cardio-damaging role of a disintegrin and metalloproteinase (ADAM)12, cardiac hypertrophy was more severe, cardiac function was lower, and mortality was higher in ADAM12 knockout mice than in wild-type mice after transverse aortic constriction surgery. The loss of ADAM12 enhanced focal adhesion- and fibrosis-related signaling pathways in the heart, which may compromise cardiac function. These results provide insights for the development of novel therapeutics that target ADAM12 to treat heart failure.

ADAM12 is A Potential Therapeutic Target Regulated by Hypomethylation in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype and currently lacks any effective targeted therapy. Since epigenetic alterations are a common event in TNBC, DNA methylation profiling can be useful for identifying potential biomarkers and therapeutic targets. Here, genome-wide DNA methylation from eight TNBC and six non-neoplastic tissues was analysed using Illumina Human Methylation 450K BeadChip. Results were validated by pyrosequencing in an independent cohort of 50 TNBC and 24 non-neoplastic samples, where protein expression was also assessed by immunohistochemistry. The functional role of disintegrin and metalloproteinase domain-containing protein 12(ADAM12) in TNBC cell proliferation, migration and drug response was analysed by gene expression silencing with short hairpin RNA. Three genes (Von Willenbrand factor C and Epidermal Growth Factor domain-containing protein (VWCE), tetraspanin-9 (TSPAN9) and ADAM12) were found to be exclusively hypomethylated in TNBC. Furthermore, ADAM12 hypomethylation was associated with a worse outcome in TNBC tissues and was also found in adjacent-to-tumour tissue and, preliminarily, in plasma from TNBC patients. In addition, ADAM12 silencing decreased TNBC cell proliferation and migration and improved doxorubicin sensitivity in TNBC cells. Our results indicate that ADAM12 is a potential therapeutic target and its hypomethylation could be a poor outcome biomarker in TNBC.

SILAC Quantitative Proteomics and Biochemical Analyses Reveal a Novel Molecular Mechanism by Which ADAM12S Promotes the Proliferation, Migration, and Invasion of Small Cell Lung Cancer Cells through Upregulating Hexokinase 1.

Small cell lung cancer (SCLC) accounts for ∼14% of total lung cancer, which is the worldwide leading cause of morbidity and mortality in cancer. Although SCLC can be treated with chemotherapy and radiotherapy, its 5 year survival rate is still below 7%. Therefore, it is essential to discover new molecules and elucidate the underlying mechanisms modulating the tumorigenesis and metastasis of SCLC for the unmet medical needs. The secreted form of A Disintegrin And Metalloproteinase 12 (ADAM12S) is highly expressed in SCLC and promotes the proliferation, migration, and invasion of SCLC cells. However, the underlying molecular mechanism is still elusive. Using stable isotope labeling by amino acids in cell culture (SILAC)-based quantitative proteomics, we identify 82 ADAM12S-regulated proteins in an SCLC cell line. Our proteomics and biochemical analyses discover that ADAM12S overexpression elevates while ADAM12 knockdown reduces the rate-limiting enzyme hexokinase 1 (HK1) in glycolysis. Through bioinformatics analyses, genetic manipulation, and in vitro assays, we further reveal that ADAM12S promotes the proliferation, colony formation, migration, and invasion of SCLC cells through upregulating HK1. This work links ADAM12S to glucose metabolic pathways in its attribution to the tumorigenesis and metastasis of SCLC cells and might provide valuable information for the exploration of therapeutic intervention for SCLC.