Suppressing Wnt signaling of the blood‒tumor barrier to intensify drug delivery and inhibit lipogenesis of brain metastases.

Lipogenesis is often highly upregulated in breast cancer brain metastases to adapt to intracranial low lipid microenvironments. Lipase inhibitors hold therapeutic potential but their intra-tumoral distribution is often blocked by the blood‒tumor barrier (BTB). BTB activates its Wnt signaling to maintain barrier properties, e.g., Mfsd2a-mediated BTB low transcytosis. Here, we reported VCAM-1-targeting nano-wogonin (W@V-NPs) as an adjuvant of nano-orlistat (O@V-NPs) to intensify drug delivery and inhibit lipogenesis of brain metastases. W@V-NPs were proven to be able to inactivate BTB Wnt signaling, downregulate BTB Mfsd2a, accelerate BTB vesicular transport, and enhance tumor accumulation of O@V-NPs. With the ability to specifically kill cancer cells in a lipid-deprived environment with IC50 at 48 ng/mL, W@V-NPs plus O@V-NPs inhibited the progression of brain metastases with prolonged survival of model mice. The combination did not induce brain edema, cognitive impairment, and systemic toxicity in healthy mice. Targeting Wnt signaling could safely modulate the BTB to improve drug delivery and metabolic therapy against brain metastases.

Nanomodulators targeting endothelial WNT and pericytes to reversibly open the blood-tumor barrier for boosted brain tumor therapy.

The blood-brain barrier (BBB)/blood-tumor barrier (BTB) impedes brain entry of most brain-targeted drugs, whether they are water-soluble or hydrophobic. Endothelial WNT signaling and neoplastic pericytes maintain BTB low permeability by regulating tight junctions. Here, we proposed nitazoxanide (NTZ) and ibrutinib (IBR) co-loaded ICAM-1-targeting nanoparticles (NI@I-NPs) to disrupt the BTB in a time-dependent, reversible, and size-selective manner by targeting specific ICAM-1, inactivating WNT signaling and depleting pericytes in tumor-associated blood vessels in breast cancer brain metastases. At the optimal NTZ/IBR mass ratio (1:2), BTB opening reached the optimum effect at 48-72 h without any sign of intracranial edema and cognitive impairment. The combination of NI@I-NPs and chemotherapeutic drugs (doxorubicin and etoposide) extended the median survival of mice with breast cancer brain metastases. Targeting BTB endothelial WNT signaling and tumor pericytes via NI@I-NPs could open the BTB to improve chemotherapeutic efficiency against brain metastases.

Association of NUDT15 gene polymorphism with adverse reaction, treatment efficacy, and dose of 6-mercaptopurine in patients with acute lymphoblastic leukemia: a systematic review and meta-analysis.

6-mercaptopurine (6-MP) serves as the backbone in the maintenance regimens of acute lymphoblastic leukemia (ALL). We aimed to evaluate the influence of NUDT15 gene polymorphism on the risk of myelosupression, hepatotoxicity and interruption of 6-MP, as well as treatment efficacy and dose of 6-MP in ALL patients. A total of 24 studies with 3,374 patients were included in this meta-analysis. We found 9-fold higher risk of 6-MP induced leukopenia (odds ratio [OR] =9.00, 95% confidence interval [CI]: 3.73-21.74) and 2.5-fold higher risk of 6-MP-induced neutropenia (OR=2.52, 95% CI: 1.72-3.69) for NUDT15 c.415C>T variant carriers in the dominant model. Moreover, we found that the dose intensity of 6-MP in ALL patients with one NUDT15 c.415C>T variant alleles (CT) was 19% less than that in wild-type patients (CC) (mean differences: 19.43%, 95% CI: -25.36 to -13.51). The tolerable dose intensity of 6-MP in NUDT15 c.415C>T homozygote variant (TT) and heterozygote variant (CT) carriers was 49% and 15% less than that in wild-type patients, respectively. The NUDT15 c.415C>T variant group (CT+TT) had seven times (OR=6.98, 95% CI: 2.83-17.22) higher risk of developing 6-MP intolerance than the CC group. However, NUDT15 c.415C>T polymorphism did not appear significantly associated with hepatotoxicity, treatment interruption or relapse incidence. We concluded that NUDT15 c.415C>T was a good predictor for 6-MP-induced myelosuppression in ALL patients. The dose intensity of 6-MP in ALL patients with NUDT15 c.415C>T variants was significantly lower than that in wild-type patients. This research provided a basis for further investigation into relations between NUDT15 gene and adverse reaction, treatment efficacy and dose intensity of 6-MP.

N6-Methyladenosine Promotes Translation of VEGFA to Accelerate Angiogenesis in Lung Cancer.

Angiogenesis is hijacked by cancer to support tumor growth. RNA modifications such as N6-methyladenosine (m6A) can regulate several aspects of cancer, including angiogenesis. Here, we find that m6A triggers angiogenesis in lung cancer by upregulating VEGFA, a central regulator of neovasculature and blood vessel growth. m6A-sequencing and functional studies confirmed that m6A modification of the 5'UTR (untranslated region) of VEGFA positively regulates its translation. Specifically, methylation of a 5'UTR internal ribosome entry site (IRES) recruited the YTHDC2/eIF4GI complex to trigger cap-independent translation initiation. Intriguingly, the m6A methylation site A856 of the 5'UTR was located within the conserved upstream open reading frame (uORF) of VEGFA IRES-A, which overcomes uORF-mediated translation suppression while facilitating G-quadruplex-induced translation of VEGFA. Targeted specific demethylation of VEGFA m6A significantly decreased expression of VEGFA and reduced lung cancer cell-driven angiogenesis. In vivo and clinical data confirmed the positive effects of m6A modification of VEGFA on angiogenesis and tumor growth of lung cancer. This study not only reveals that the m6A/VEGFA axis is a potential target for lung cancer therapy but also expands our understanding of the impact of m6A modification of IRES in the 5'UTR of mRNA on translation regulation. SIGNIFICANCE: Methylation of the 5'UTR IRES of VEGFA mRNA increases cap-independent translation via recruitment of the YTHDC2/eIF4GI complex, which stimulates angiogenesis to promote lung tumor growth.

DH5α Outer Membrane-Coated Biomimetic Nanocapsules Deliver Drugs to Brain Metastases but not Normal Brain Cells via Targeting GRP94.

Receptor-mediated vesicular transport has been extensively developed to penetrate the blood-brain barrier (BBB) and has emerged as a class of powerful brain-targeting delivery technologies. However, commonly used BBB receptors such as transferrin receptor and low-density lipoprotein receptor-related protein 1, are also expressed in normal brain parenchymal cells and can cause drug distribution in normal brain tissues and subsequent neuroinflammation and cognitive impairment. Here, the endoplasmic reticulum residing protein GRP94 is found upregulated and relocated to the cell membrane of both BBB endothelial cells and brain metastatic breast cancer cells (BMBCCs) by preclinical and clinical investigations. Inspired by that Escherichia coli penetrates the BBB via the binding of its outer membrane proteins with GRP94, avirulent DH5α outer membrane protein-coated nanocapsules (Omp@NCs) are developed to cross the BBB, avert normal brain cells, and target BMBCCs via recognizing GRP94. Embelin (EMB)-loaded Omp@EMB specifically reduce neuroserpin in BMBCCs, which inhibits vascular cooption growth and induces apoptosis of BMBCCs by restoring plasmin. Omp@EMB plus anti-angiogenic therapy prolongs the survival of mice with brain metastases. This platform holds the translational potential to maximize therapeutic effects on GRP94-positive brain diseases.

ß2-Adrenergic Receptor Enhances the Alternatively Activated Macrophages and Promotes Biliary Injuries Caused by Helminth Infection.

The autonomic nervous system has been studied for its involvement in the control of macrophages; however, the mechanisms underlying the interaction between the adrenergic receptors and alternatively activated macrophages (M2) remain obscure. Using FVB wild-type and beta 2 adrenergic receptors knockout, we found that ß2-AR deficiency alleviates hepatobiliary damage in mice infected with C. sinensis. Moreover, ß2-AR-deficient mice decrease the activation and infiltration of M2 macrophages and decrease the production of type 2 cytokines, which are associated with a significant decrease in liver fibrosis in infected mice. Our in vitro results on bone marrow-derived macrophages revealed that macrophages from Adrb2-/- mice significantly decrease M2 markers and the phosphorylation of ERK/mTORC1 induced by IL-4 compared to that observed in M2 macrophages from Adrb2+/+ . This study provides a better understanding of the mechanisms by which the ß2-AR enhances type 2 immune response through the ERK/mTORC1 signaling pathway in macrophages and their role in liver fibrosis.

Palmitoylation in Crohn's disease: Current status and future directions.

S-palmitoylation is one of the most common post-translational modifications in nature; however, its importance has been overlooked for decades. Crohn's disease (CD), a subtype of inflammatory bowel disease (IBD), is an autoimmune disease characterized by chronic inflammation involving the entire gastrointestinal tract. Bowel damage and subsequent disabilities caused by CD are a growing global health issue. Well-acknowledged risk factors for CD include genetic susceptibility, environmental factors, such as a westernized lifestyle, and altered gut microbiota. However, the pathophysiological mechanisms of this disorder are not yet comprehensively understood. With the rapidly increasing global prevalence of CD and the evident role of S-palmitoylation in CD, as recently reported, there is a need to investigate the relationship between CD and S-palmitoylation. In this review, we summarize the concept, detection, and function of S-palmitoylation as well as its potential effects on CD, and provide novel insights into the pathogenesis and treatment of CD.

N6-Methyladenosine Regulates the Expression and Secretion of TGFß1 to Affect the Epithelial-Mesenchymal Transition of Cancer Cells.

N6-methyladenosine (m6A) is the most abundant modification on eukaryotic mRNA, which regulates all steps of the mRNA life cycle. An increasing number of studies have shown that m6A methylation plays essential roles in tumor development. However, the relationship between m6A and the progression of cancers remains to be explored. Here, we reported that transforming growth factor-ß (TGFß1)-induced epithelial-mesenchymal transition (EMT) was inhibited in methyltransferase-like 3 (METTL3) knockdown (Mettl3Mut/-) cells. The expression of TGFß1 was up-regulated, while self-stimulated expression of TGFß1 was suppressed in Mettl3Mut/- cells. We further revealed that m6A promoted TGFB1 mRNA decay, but impaired TGFB1 translation progress. Besides this, the autocrine of TGFß1 was disrupted in Mettl3Mut/- cells via interrupting TGFß1 dimer formation. Lastly, we found that Snail, which was down-regulated in Mettl3Mut/- cells, was a key factor responding to TGFß1-induced EMT. Together, our research demonstrated that m6A performed multi-functional roles in TGFß1 expression and EMT modulation, suggesting the critical roles of m6A in cancer progression regulation.

N6-methyladenosine induced miR-143-3p promotes the brain metastasis of lung cancer via regulation of VASH1.

BACKGROUND: Brain metastasis (BM) is one of the principal causes of mortality for lung cancer patients. While the molecular events that govern BM of lung cancer remain frustrating cloudy. METHODS: The miRNA expression profiles are checked in the paired human BM and primary lung cancer tissues. The effect of miR-143-3p on BM of lung cancer cells and its related mechanisms are investigated. RESULTS: miR-143-3p is upregulated in the paired BM tissues as compared with that in primary cancer tissues. It can increase the invasion capability of in vitro blood brain barrier (BBB) model and angiogenesis of lung cancer by targeting the three binding sites of 3'UTR of vasohibin-1 (VASH1) to inhibit its expression. Mechanistically, VASH1 can increase the ubiquitylation of VEGFA to trigger the proteasome mediated degradation, further, it can endow the tubulin depolymerization through detyrosination to increase the cell motility. m6A methyltransferase Mettl3 can increase the splicing of precursor miR-143-3p to facilitate its biogenesis. Moreover, miR-143-3p/VASH1 axis acts as adverse prognosis factors for in vivo progression and overall survival (OS) rate of lung cancer. CONCLUSIONS: Our work implicates a causal role of the miR-143-3p/VASH1 axis in BM of lung cancers and suggests their critical roles in lung cancer pathogenesis.