BRCC36 Deubiquitinates HMGCR to Regulate the Interplay Between Ferroptosis and Pyroptosis

Various forms of programmed cell death (PCD) exhibit distinct characteristics depending on their specific molecular mechanisms, and there are interactions among these different forms. Ferroptosis, which is related to autophagy and apoptosis, has an unknown potential interaction with pyroptosis. This study revealed a mutually antagonistic relationship between ferroptosis and pyroptosis, with 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) playing a key role in their interaction. It is found that HMGCR predominantly localized to mitochondria during ferroptosis but shifted to the endoplasmic reticulum following treatment with a pyroptosis inducer. Furthermore, this study demonstrated that BRCC36 (BRCA1/BRCA2-containing complex subunit 36) deubiquitinated HMGCR in a manner dependent on deubiquitinating enzyme (DUB) activity, and inhibited ferroptosis and promoted pyroptosis. Moreover, as an oncogene in hepatocellular carcinoma (HCC), BRCC36 promoted cancer cell proliferation, migration, invasion, and tumor growth. Thiolutin, an inhibitor of BRCC36, effectively suppressed the interaction between BRCC36 and HMGCR, leading to the inhibition of HCC growth. Therefore, targeting BRCC36 can offer a novel and promising therapeutic strategy for HCC treatment. In conclusion, these findings provide new theoretical evidence for further characterizing tumor heterogeneity and offer new molecular targets for the diagnosis and treatment of HCC.

Precisely Inhibiting Excessive Intestinal Epithelial Cell Apoptosis to Efficiently Treat Inflammatory Bowel Disease with Oral Pifithrin-α Embedded Nanomedicine (OPEN)

The increased incidence of inflammatory bowel disease (IBD) has seriously affected the life quality of patients. IBD develops due to excessive intestinal epithelial cell (IEC) apoptosis, disrupting the gut barrier, colonizing harmful bacteria, and initiating persistent inflammation. The current therapeutic approaches that reduce inflammation are limited. Although IBD can be treated significantly by directly preventing IEC apoptosis, achieving this therapeutic approach remains challenging. Accordingly, the authors are the first to develop an oral pifithrin-α (PFTα, a highly specific p53 inhibitor) embedded nanomedicine (OPEN) to effectively treat IBD by inhibiting excessive IEC apoptosis. As a major hub for various stressors, p53 is a central determinant of cell fate, and its inhibition can effectively reduce excessive IEC apoptosis. The tailored OPEN can precisely inhibit the off-target and inactivation resulting from PFTα entry into the bloodstream. Subsequently, it persistently targets IBD lesions with high specificity to inhibit the pathological events caused by excessive IEC apoptosis. Eventually, OPEN exerts a significant curative effect compared with the clinical first-line drugs 5-aminosalicylic acid (5-ASA) and dexamethasone (DEX). Consequently, the OPEN therapeutic strategy provides new insights into comprehensive IBD therapy.

Efficient Therapy of Inflammatory Bowel Disease (IBD) with Highly Specific and Durable Targeted Ta2 C Modified with Chondroitin Sulfate (TACS)

Non-invasive localization of lesions and specific targeted therapy are still the main challenges for inflammatory bowel disease (IBD). Ta, as a medical metal element, has been widely used in the treatment of different diseases because of its excellent physicochemical properties but is still far from being explored in IBD. Here, Ta2 C modified with chondroitin sulfate (CS) (TACS) is evaluated as a highly targeted therapy nanomedicine for IBD. Specifically, TACS is modified with dual targeting CS functions due to IBD lesion-specific positive charges and high expression of CD44 receptors. Thanks to the acid stability, sensitive CT imaging function, and strong reactive oxygen species (ROS) elimination ability, oral TACS can accurately locate and delineate IBD lesions through non-invasive CT imaging, and specifically targeted treat IBD effectively because high levels of ROS are a central factor in the progression of IBD. As expected, TACS has much better imaging and therapeutic effects than clinical CT contrast agent and first-line drug 5-aminosalicylic acid, respectively. The mechanism of TACS treatment mainly involves protection of mitochondria, elimination of oxidative stress, inhibiting macrophage M1 polarization, protection of intestinal barrier, and restoration of intestinal flora balance. Collectively, this work provides unprecedented opportunities for oral nanomedicines to targeted therapy of IBD.

The NLRP11 Protein Bridges the Histone Lysine Acetyltransferase KAT7 to Acetylate Vimentin in the Early Stage of Lung Adenocarcinoma

Accumulation of vimentin is the core event in epithelial-mesenchymal transition (EMT). Post-translational modifications have been widely reported to play crucial roles in imparting different properties and functions to vimentin. Here, a novel modification of vimentin, acetylated at Lys104 (vimentin-K104Ac) is identified, which is stable in lung adenocarcinoma (LUAD) cells. Mechanistically, NACHT, LRR, and PYD domain-containing protein 11 (NLRP11), a regulator of the inflammatory response, bind to vimentin and promote vimentin-K104Ac expression, which is highly expressed in the early stages of LUAD and frequently appears in vimentin-positive LUAD tissues. In addition, it is observed that an acetyltransferase, lysine acetyltransferase 7 (KAT7), which binds to NLRP11 and vimentin, directly mediates the acetylation of vimentin at Lys104 and that the cytoplasmic localization of KAT7 can be induced by NLRP11. Malignant promotion mediated by transfection with vimentin-K104Q is noticeably greater than that mediated by transfection with vimentin-WT. Further, suppressing the effects of NLRP11 and KAT7 on vimentin noticeably inhibited the malignant behavior of vimentin-positive LUAD in vivo and in vitro. In summary, these findings have established a relationship between inflammation and EMT, which is reflected via KAT7-mediated acetylation of vimentin at Lys104 dependent on NLRP11.

In-Site Grown NiFeOOH Nanosheets Foam Directly as Robust Electrocatalyst for Efficient Urea Oxidation Application

In this work, a series of morphology-controlled NiFeOOH nanosheets were directly developed through a one-step mild in-situ acid-etching hydrothermal process. Benefiting from the ultrathin interwoven geometric structure and most favorable electron transport structure, the NiFeOOH nanosheets synthesized under 120 °C (denoted as NiFe_120) exhibited the optimal electrochemical performance for urea oxidation reaction (UOR). An overpotential of merely 1.4 V was required to drive the current density of 100 mA cm-2 , and the electrochemical activity remains no change even after 5000 cycles' accelerated degradation test. Moreover, the assembled urea electrolysis set by using the NiFe_120 as bifunctional catalysts presented a reduced potential of 1.573 V at 10 mA cm-2 , which was much lower than that of overall water splitting. We believe this work will lay a foundation for developing high-performance urea oxidation catalysts for the large-scale production of hydrogen and purification of urea-rich sewage.