Antileukemic effects of topoisomerase I inhibitors mediated by de-SUMOylase SENP1

SENP2-NDR2-p21 axis modulates lung cancer cell growth

Sentrin/small ubiquitin-like modifier (SUMO)-specific proteases (SENPs) perform pivotal roles in SUMO maturation and recycling, which modulate the balance of SUMOylation/de-SUMOylation and spatiotemporal functions of SUMOylation targets. The malfunction of SENPs often results in cellular dysfunction and various diseases. However, studies rarely investigated the correlation between SENP2 and lung cancer. This study revealed that SENP2 is a required contributor to lung cancer-cell growth and targets nuclear Dbf2-related 2 (NDR2, also known as serine/threonine kinase 38L or STK38L) for de-SUMOylation, which improves NDR2 kinase activity. This condition leads to the instability of downstream target p21 in accelerating the G1/S cell cycle transition and suggests SENP2 as a promising therapeutic target for lung cancer in the future. Specifically, astragaloside IV, an active ingredient of Jinfukang Oral Liquid (JOL, a clinical combination antilung cancer drug approved by the National Food and Drug Administration (FDA) of China), can repress lung cancer-cell growth via the SENP2-NDR2-p21 axis, which provides new insights into the molecular mechanism of JOL for lung cancer treatment.

Etoposide-induced SENP8 confers a feed-back drug resistance on acute lymphoblastic leukemia cells

Chemotherapy is the most common treatment for acute lymphoblastic leukemia (ALL). However, many ALL patients eventually develop relapse and treating relapsed ALL has always been challenging. Therefore, exploring the resistance mechanism of chemotherapeutic drugs and proposing feasible intervention strategies are of great significance for ALL treatment. Here, we show that SENP8, whose coding protein is an important deNEDDylase targeting the substrate for deNEDDylation, is highly expressed in relapsed ALL specimens. Interestingly, overexpressing SENP8 specifically reduces the chemosensitivity of ALL cells to etoposide (VP-16) and significantly alleviates the proapoptotic effect of VP-16 on ALL cells. By contrast, NEDDylation inhibition reduces the chemosensitivity of ALL cells to VP-16. Furthermore, VP-16 induces SENP8 accumulation and the instability of MDM2 as well as the stabilization of p53 in ALL cells, and SENP8 knockdown can sensitize ALL cells to VP-16. Our study reveals a novel function of SENP8 in ALL and that VP-16-induced SENP8 confers a feed-back drug resistance on ALL cells, suggesting a possibility of overcoming the chemotherapeutic resistance to VP-16 via targeting SENP8.

Emerging role of SENP1 in tumorigenesis and cancer therapy

Acting as a cysteine protease, small ubiquitin-like modifier (SUMO)/sentrin-specific protease1 (SENP1) involved in multiple physiological and pathological processes through processing the precursor SUMO protein into mature form and deSUMOylating target protein. It has been reported that SENP1 is highly expressed and plays a carcinogenic role in various cancers. In this paper, we mainly explore the function and mechanism of SENP1 in tumor cell proliferation, apoptosis, invasion, metastasis, stemness, angiogenesis, metabolism and drug resistance. Furthermore, the research progress of SENP1 inhibitors for cancer treatment is introduced. This study aims to provide theoretical references for cancer therapy by targeting SENP1.

The emerging roles of SUMOylation in pulmonary diseases

Small ubiquitin-like modifier mediated modification (SUMOylation) is a critical post-translational modification that has a broad spectrum of biological functions, including genome replication and repair, transcriptional regulation, protein stability, and cell cycle progression. Perturbation or deregulation of a SUMOylation and deSUMOylation status has emerged as a new pathophysiological feature of lung diseases. In this review, we highlighted the link between SUMO pathway and lung diseases, especially the sumoylated substrate such as C/EBPα in bronchopulmonary dysplasia (BDP), PPARγ in pneumonia, TFII-I in asthma, HDAC2 in chronic obstructive pulmonary disease (COPD), KLF15 in hypoxic pulmonary hypertension (HPH), SMAD3 in idiopathic pulmonary fibrosis (IPF), and YTHDF2 in cancer. By exploring the impact of SUMOylation in pulmonary diseases, we intend to shed light on its potential to inspire the development of innovative diagnostic and therapeutic strategies, holding promise for improving patient outcomes and overall respiratory health.

SUMO specific peptidase 1 decreases after induction treatment, and its reduction predicts lower disease risk, better treatment response, longer survival of acute myeloid leukemia

Small ubiquitin-related modifier-specific peptidase 1 (SENP1) takes part in the pathogenesis and progression of hematological malignancies, while its clinical role in acute myeloid leukemia (AML) is unclear. This study aimed to explore the potential of SENP1 to serve as a biomarker reflecting disease risk, treatment response, and survival of AML. A total of 110 AML patients, 30 disease controls (DCs), and 30 healthy controls (HCs) were included. SENP1 in bone marrow samples was detected by RT-qPCR. SENP1 was the top in AML patients (median (interquartile range (IQR)): 2.429 (1.854-3.772)), the second top in DCs (median (IQR): 1.587 (1.023-2.217)), and the lowest in HCs (median (IQR): 0.992 (0.806-1.702)) (p < 0.001). In AML patients, SENP1 was positively associated with white blood cells (rs = 0.210, p = 0.028) and bone marrow blasts (rs = 0.212, p = 0.026) but negatively linked to Inv(16) or t(16;16) presence (p = 0.040). Furthermore, SENP1 was decreased post-treatment vs. at baseline (before induction treatment) in total AML patients (p < 0.001), and in patients with CR (p < 0.001), but not in patients with non-CR (p = 0.055). Additionally, SENP1 at baseline slightly (p = 0.050) but SENP1 post-treatment dramatically (p < 0.001) decreased in patients with CR compared to those with non-CR. Notably, low SENP1 at baseline was related to prolonged EFS (p = 0.007) and OS (p = 0.039); meanwhile, declined SENP1 post-induction treatment showed a more predominant linkage with satisfied EFS (p < 0.001) and OS (p < 0.001). SENP1 is decreased after induction therapy, whose reduction is related to low disease risk, favorable treatment response, and prolonged survival of AML.

ACLY-β-catenin axis modulates hepatoblastoma cell proliferation

HB (hepatoblastoma) is most common in children with liver cancer and few options for treating HB. Thus, it is of great significance to investigate the regulatory mechanism of HB and/or identify new therapeutic targets for clinical treatment of HB. Here, we showed that ACLY (ATP citrate lyase), an important lipometabolic enzyme for de novo biosynthesis of fatty acids and steroids, has a higher expression in HB tissues than noncancerous tissues, and is required for HB cell proliferation. Moreover, knocking down ACLY in HB cells caused severe S-phase arrest and apoptosis. Mechanistically, ACLY knockdown significantly silenced the Wnt signaling pathway and reduced β-catenin expression in HB cells. Conversely, the apoptotic alleviation of HB cells by overexpressing ACLY was blocked by silencing β-catenin, suggesting the modulation of HB cells by ACLY-β-catenin axis. Our results uncovered the role of ACLY in HB cells and presented a theoretical approach for HB targeted therapy in the future.