Tumor Xenografts Research Articles

A B7-H3–Targeted CD28 Bispecific Antibody Enhances the Activity of Anti–PD-1 and CD3 T-cell Engager Immunotherapies

Abstract T-cell activation is a multistep process requiring T-cell receptor engagement by peptide–MHC complexes (Signal 1) coupled with CD28-mediated costimulation (Signal 2). Tumors typically lack expression of CD28 ligands, so tumor-specific Signal 1 (e.g., neoepitope presentation) without costimulation may be ineffective or even induce T-cell anergy. We designed the bispecific antibody XmAb808 to co-engage the tumor-associated antigen B7-H3 with CD28 to promote T-cell costimulation within the tumor microenvironment. XmAb808 costimulation was measured by its ability to activate and expand T cells and enhance T cell–mediated cancer cell killing in cocultures of human peripheral blood mononuclear cells and cancer cells and in mice engrafted with human peripheral blood mononuclear cells and tumor xenografts. XmAb808 avidly bound cancer cells and stimulated IL2 and IFNγ secretion from T cells cocultured with cancer cells engineered to deliver Signal 1 to T cells via a surface-expressed anti-CD3 antibody. XmAb808 enhanced expression of the antiapoptotic factor Bcl-xL and CD25, promoting survival and IL2-dependent expansion of T cells coupled with increased T cell–mediated cytotoxicity in vitro. XmAb808 combined with an EpCAM×CD3 bispecific antibody to enhance target cell killing through IL2-dependent expansion of CD25+ T cells. This combination also suppressed pancreatic tumor xenograft growth in mice. Furthermore, XmAb808 combined with an anti–programmed cell death protein 1 antibody to suppress breast tumor xenograft growth in mice. XmAb808 as monotherapy and in combination with an anti–programmed cell death protein 1 antibody is currently in clinical development in patients with advanced solid tumors. Our results suggest that XmAb808 may also combine with tumor antigen–targeted anti-CD3 (Signal 1) T-cell engagers.

Mutant-selective AKT inhibition through lysine targeting and neo-zinc chelation.

Somatic alterations in the oncogenic kinase AKT1 have been identified in a broad spectrum of solid tumours. The most common AKT1 alteration replaces Glu17 with Lys (E17K) in the regulatory pleckstrin homology domain1, resulting in constitutive membrane localization and activation of oncogenic signalling. In clinical studies, pan-AKT inhibitors have been found to cause dose-limiting hyperglycaemia2-6, which has motivated the search for mutant-selective inhibitors. We exploited the E17K mutation to design allosteric, lysine-targeted salicylaldehyde inhibitors with selectivity for AKT1 (E17K) over wild-type AKT paralogues, a major challenge given the presence of three conserved lysines near the allosteric site. Crystallographic analysis of the covalent inhibitor complex unexpectedly revealed an adventitious tetrahedral zinc ion that coordinates two proximal cysteines in the kinase activation loop while simultaneously engaging the E17K-imine conjugate. The salicylaldimine complex with AKT1 (E17K), but not that with wild-type AKT1, recruits endogenous Zn2+ in cells, resulting in sustained inhibition. A salicylaldehyde-based inhibitor was efficacious in AKT1 (E17K) tumour xenograft models at doses that did not induce hyperglycaemia. Our study demonstrates the potential to achieve exquisite residence-time-based selectivity for AKT1 (E17K) by targeting the mutant lysine together with Zn2+ chelation by the resulting salicylaldimine adduct.

A Cancer-Specific Anti-Podoplanin Monoclonal Antibody, PMab-117-mG2a Exerts Antitumor Activities in Human Tumor Xenograft Models

Podoplanin (PDPN) overexpression is associated with poor clinical outcomes in various tumors. PDPN is involved in malignant tumor progression by promoting invasiveness and metastasis. Therefore, PDPN is considered a promising target of monoclonal antibody (mAb)-based therapy. Because PDPN also plays an essential role in normal cells such as kidney podocytes, cancer specificity is required to reduce adverse effects on normal cells. We developed a cancer-specific mAb (CasMab) against PDPN, PMab-117 (rat IgM, kappa), by immunizing rats with PDPN-overexpressed glioblastoma cells. The recombinant mouse IgG2a-type PMab-117 (PMab-117-mG2a) reacted with the PDPN-positive tumor PC-10 and LN319 cells but not with PDPN-knockout LN319 cells in flow cytometry. PMab-117-mG2a did not react with normal kidney podocytes and normal epithelial cells from the lung bronchus, mammary gland, and corneal. In contrast, one of the non-CasMabs against PDPN, NZ-1, showed high reactivity to PDPN in both tumor and normal cells. Moreover, PMab-117-mG2a exerted antibody-dependent cellular cytotoxicity in the presence of effector splenocytes. In the human tumor xenograft models, PMab-117-mG2a exhibited potent antitumor effects. These results indicated that PMab-117-mG2a could be applied to antibody-based therapy against PDPN-expressing human tumors while reducing the adverse effects.

Host-Guest Adduct as a Stimuli-Responsive Prodrug: Enzyme-Triggered Self-Assembly Process of a Short Peptide Within Mitochondria to Induce Cell Apoptosis.

To address the issue of nonspecific biodistribution of a chemotherapeutic drug, stable [2]pseudorotaxane complexes (PK@CAOPP and PR@CAOPP) are used to demonstrate a proof of concept. Cationic -PPh3 + moiety in CAOPP allows specific localization of the PK@CAOPP/ PR@CAOPP in the mitochondrial membrane (MM). Electrostatic interaction between the cationic LysinePK or ArgininePR moiety and the negatively charged phosphoesterCAOPP functionality in CAOPP favours strong adduct formation. The ALP-induced hydrolytic cleavage of the phosphoester moiety in cancer cells triggers dephosphorylation and releases PK/ PR moiety from PK@CAOPP/PR@CAOPP. PK or PR, derived from the Phe-Phe dipeptide, formed fibril-like molecular aggregates in the MM to induce dysfunction, depolarization, ROS generation and apoptotic MCF7 cell death. Such phenomena were not observed in ALP-negative HEK293 normal cells. These propositions were confirmed through control studies using NBDK and PE, other guest molecules. Smaller size and inclusion of the short peptides (PK or PR) within the hydrophobic interior of CAOPP, were attributed to their stability in blood serum. Thus, we have demonstrated the use of supramolecular adducts as a potential therapeutic option for treating cancer cells without affecting healthy cells. The efficacy was also established with an in-vivo MCF7 tumour xenograft model using Balb/c nude mice.

NEK2 Promotes ESCC Malignant Progression by Inhibiting Cellular Senescence via the FOXM1/c-Myc/p27 Signaling Pathway.

Never in mitosis gene A (NIMA)-related kinase 2 (NEK2) is a crucial serine-threonine kinase involved in the process of cell mitosis. However, the precise relationship between NEK2 and esophageal squamous cell carcinoma (ESCC) remains inadequately understood. NEK2 expression in ESCC tissues was assessed through bioinformatics analysis, reverse transcription-quantitative PCR (RT-qPCR) and immunohistochemistry, revealing a correlation with ESCC patient prognosis. Cultured ESCC cells and human normal esophageal epithelial cells (HEEC) were used to investigate the effects of NEK2 knockdown on the development and progression of ESCC by integrated confluence algorithm, colony formation, wound-healing, transwell, and ESCC xenograft tumor model, in vitro and in vivo. In ESCC tissues, NEK2 was found to be significantly upregulated, and its expression correlated with poor prognosis in ESCC patients. NEK2 may facilitate ESCC development by regulating cell proliferation, migration, and invasion. Additionally, results from in vivo experiments suggested that NEK2 knockdown can inhibit tumor growth. Moreover, forkhead box M1 (FOXM1) was identified as a potential downstream target of NEK2 in the regulation of ESCC, with its overexpression reversing the effects of NEK2 knockdown on ESCC. Mechanistic studies also indicated that NEK2 may promote the malignant progression of ESCC by inhibiting cellular senescence through the activation of the FOXM1/c-Myc/p27 signaling pathways, which may provide a novel perspective for the management of ESCC.

PTPN20 promotes metastasis through activating NF-κB signaling in triple-negative breast cancer.

Cancer metastasis remains a major challenge in the clinical management of triple-negative breast cancer (TNBC). The NF-κB signaling pathway has been implicated as a crucial factor in the development of metastases, but the underlying molecular mechanisms remain largely unclear. PTPN20 expression was evaluated using data from the Sweden Cancerome Analysis Network-Breast and The Cancer Genome Atlas database, as well as by western blotting and immunohistochemistry in 88 TNBC patients. The ability of PTPN20 to activate NF-κB was assessed by luciferase reporter assays. The effects of PTPN20 overexpression and knockdown via short hairpin RNA were examined in TNBC cell lines by wound healing and transwell matrix penetration assays. Additionally, we analyzed the growth and metastasis abilitiy of 4T1 xenograft tumors in nude mice. PTPN20 levels were elevated in TNBC cell lines and patient samples compared to controls, and higher protein levels correlated with metastasis-free survival. Overexpression of PTPN20 enhanced migration and invasion in vitro, and promoted lung metastasis in vivo. Our finding revealed that PTPN20 activates NF-κB signaling by dephosphorylating p65 at Ser468, preventing its binding to COMMD1, thereby protecting p65 from degradation. Downregulation of PTPN20 effectively inhibit, while p65 S468A mutant restored the migratory and invasive abilities of TNBC cells. Collectively, our results demonstrate that PTPN20 plays a critical role in TNBC metastasis through the activation of NF-κB signaling. We propose that PTPN20 may serve as a novel prognostic marker and potential therapeutic target for the treatment of TNBC.

IMPA1-derived inositol maintains stemness in castration-resistant prostate cancer via IMPDH2 activation.

Acquisition of prostate cancer stem cells (PCSCs) manifested during androgen ablation therapy (ABT) contributes to castration-resistant prostate cancer (CRPC). However, little is known about the specific metabolites critically orchestrating this process. Here, we show that IMPA1-derived inositol enriched in PCSCs is a key metabolite crucially maintaining PCSCs for CRPC progression and ABT resistance. Notably, conditional Impa1 knockout in the prostate abrogates the pool and properties of PCSCs to orchestrate CRPC progression and prolong the survival of TRAMP mice. IMPA1-derived inositol serves as a cofactor that directly binds to and activates IMPDH2, which synthesizes guanylate nucleotides for maintaining PCSCs with ARlow/- features leading to CRPC progression and ABT resistance. IMPA1/inositol/IMPDH2 axis is upregulated in human prostate cancer, and its overexpression predicts poor survival outcomes. Genetically and pharmacologically targeting the IMPA1/inositol/IMPDH2 axis abrogates CRPC and overcomes ABT resistance in various CRPC xenografts, patient-derived xenograft (PDX) tumor models, and TRAMP mouse models. Our study identifies IMPDH2 as an inositol sensor whose activation by inositol represents a key mechanism for maintaining PCSCs for CRPC and ABT resistance.

Nuclear porcupine mediates XRCC6/Ku70 S-palmitoylation in the DNA damage response

BackgroundThe activation of the DNA damage response (DDR) heavily relies on post-translational modifications (PTMs) of proteins, which play a crucial role in the prevention of genetic instability and tumorigenesis. Among these PTMs, palmitoylation is a highly conserved process that is dysregulated in numerous cancer types. However, its direct involvement in the DDR and the underlying mechanisms remain unclear.MethodsCRISPR-Cas9 technology was used to generate the PORCN KO and PORCN NLS KO cell lines. The effects of PORCN NLS in the DDR were verified by colony formation assays, MTT assays, the DR/EJ5 homologous recombination/non-homologous end-joining reporter system, xenograft tumor growth and immunofluorescence. Mechanisms were explored by mass spectrometry, acyl-biotin exchange (ABE) palmitoylation assay, Click-iT assay, cell subcellular fractionation assay, Western blot analysis, and in vivo and in vitro co-immunoprecipitation.ResultsIn this study, we introduce evidence that Porcupine (PORCN) is an integral component of and plays a critical role in the DDR. PORCN deficiency hampers nonhomologous end joining (NHEJ) and highly sensitizes cells to ionizing radiation (IR) both in vitro and in vivo. We also provide evidence that PORCN possesses a nuclear fraction (nPORCN) with S-acyltransferase activity, unlike its membrane-bound O-acyltransferase in the endoplasmic reticulum. Furthermore, we show that nPORCN is necessary for the successful activation of NHEJ. Using mass spectrometry, we reveal the existence of an nPORCN complex and show that nPORCN mediates the S-palmitoylation of XRCC6/Ku70 at five specific cysteine sites in response to IR. Mutation of these sites causes a substantial increase in radiosensitivity and delays NHEJ. Additionally, we present evidence that nPORCN-dependent Ku70 palmitoylation is required for DNA-PKcs/Ku70/Ku80 complex formation.ConclusionOur findings underscore the crucial role of nPORCN-dependent Ku70 S-palmitoylation in the DDR.

O-GlcNAcylation of hexokinase 2 modulates mitochondrial dynamics and enhances the progression of lung cancer.

Non-small cell lung cancer (NSCLC) stands as the prevailing manifestation of lung cancer, with current therapeutic modalities linked to a dismal prognosis, necessitating further advancements. Hexokinase 2 (HK2), a critical enzyme positioned on the mitochondrial membrane, exerts control over diverse biological pathways, thereby regulating cancer. Nevertheless, the precise role and mechanism of HK2 in NSCLC remain inadequately elucidated, warranting comprehensive investigation. HK2 expression in NSCLC tissues and cell lines was detected through immunohistochemistry and western blot analysis. Concurrently, shRNA assays were applied to scrutinize the impact of HK2 on cell proliferation, apoptosis, migration, and invasion processes in NSCLC cell lines, utilizing CCK8, flow cytometry, wound-healing assay, and transwell techniques. The involvement of HK2 in mitochondrial dynamics was probed through western blot analysis, mitochondrial membrane potential assay, and assessment of ROS generation. Next, the functional role of HK2 was assessed by examining its influence on xenograft tumor growth in nude mice in vivo. Further research has demonstrated that HK2 played a role in NSCLC through its O-GlcNAcylation process. The results of the study revealed that HK2 O-GlcNAcylation promoted the proliferation, migration, and invasive characteristics of NSCLC cells, while alleviating mitochondrial damage, whereas O-GlcNAcylation inactivation yielded the opposite effect. Furthermore, in vivo experiments in nude mice illustrated that HK2 O-GlcNAcylation could stimulate tumor growth in NSCLC. These results suggested that HK2 may impact mitochondrial dynamics in NSCLC through its O-GlcNAcylation, thereby contributing to the progression of NSCLC.

Zymogen granule protein 16B (ZG16B) is a druggable epigenetic target to modulate the mammary extracellular matrix.

High tissue density of the mammary gland is considered a pro-tumorigenic factor, hence suppressing the stimuli that induce matrix buildup carries the potential for cancer interception. We found that in non-malignant mammary epithelial cells the combination of the chemopreventive agents bexarotene (Bex) and carvedilol (Carv) suppresses the zymogen granule protein 16B (ZG16B, PAUF) through an interaction of ARID1A with a proximal enhancer. Bex + Carv also reduced ZG16B levels invivo in normal breast tissue and MDA-MB231 tumor xenografts. The relevance of ZG16B is underscored by ongoing clinical trials targeting ZG16B in pancreatic cancers, but its role in breast cancer development is unclear. In immortalized mammary epithelial cells, secreted recombinant ZG16B stimulated mitogenic kinase phosphorylation, detachment and mesenchymal characteristics, and promoted proliferation, motility and clonogenic growth. Highly concerted induction of specific laminin, collagen and integrin isoforms indicated a shift in matrix properties toward increased density and cell-matrix interactions. Exogenous ZG16B alone blocked Bex + Carv-mediated control of cell growth and migration, and antagonized Bex + Carv-induced gene programs regulating cell adhesion and migration. In breast cancer cells ZG16B induced colony formation and anchorage-independent growth, and stimulated migration in a PI3K/Akt-dependent manner. In contrast, Bex + Carv inhibited colony formation, reduced Ki67 levels, ZG16B expression and glucose uptake in MDA-MB231 xenografts. These data establish ZG16B as a druggable pro-tumorigenic target in breast cell transformation and suggest a key role of the matrisome network in rexinoid-dependent antitumor activity.

TLR3 activation enhances antitumor effects of sorafenib in hepatocellular carcinoma by activating NK cell functions through ERK and NF-κB pathways

Background Sorafenib is a standard therapeutic agent for advanced hepatocellular carcinoma (HCC). However, its efficacy is moderate, as the survival of patients is prolonged for only a few months, and the response rate is low. The mechanism of low efficacy remains unclear. In this study, we investigated the effect of Toll-like receptor 3 (TLR3) on the effects of sorafenib on HCC. Methods Polyinosinic-polycytidylic acid [poly(I: C)] was used as a double-stranded RNA analog and TLR3 agonist in subsequent experiments. After orthotopic implantation of HCC tumors in BALBc nu/nu or C57BL/6 mice, survival time, tumor growth, and metastasis in the abdomen and lungs were analyzed. Flow cytometry and cytotoxicity assays were used to analyze NK cells isolated from the spleen or peripheral blood. ELISA was used to detect the expression of plasma interferon (IFN)-γ and monocyte chemoattractant protein (MCP)-1. In addition, the expression of phosphorylated-extracellular regulated kinase 1/2 (pERK1/2), phosphorylated-protein kinase B (pAKT), ERK1/2 and AKT was analyzed by Western blotting. Results Sorafenib reduced the number and activity of NK cells in tumor-bearing mice and simultaneously decreased the levels of MCP-1 and IFN-γ in the plasma. The combination of sorafenib and poly(I: C) synergistically inhibited tumor growth and metastasis in tumor xenograft mice and prolonged survival. Poly(I: C) not only exerts a direct inhibitory effect on tumor growth and metastasis by targeting the TLR3 receptor on tumor cells but also facilitates the proliferation and activation of NK cells, indirectly impeding tumor progression. Mechanistically, poly(I: C) decreased the sorafenib-induced inhibition of ERK phosphorylation and increased the phosphorylation of IκB in NK cells, thereby enhancing NK cell function. Conclusion Activation of TLR3 can enhance the antitumor effect of sorafenib on HCC. The combination of a TLR3 activator and sorafenib may be a new strategy for the treatment of HCC.

ST2L promotes VEGFA-mediated angiogenesis in gastric cancer by activating TRAF6/PI3K/Akt/NF-κB pathway via IL-33

Suppression of Tumorigenicity 2 (ST2) is a member of the interleukin-1 receptor/ Toll-like receptor superfamily, and its specific ligand is Interleukin-33 (IL-33). IL-33/ ST2 signaling has been implicated in numerous inflammatory and allergic diseases, as well as in promoting malignant behavior of tumor cells and angiogenesis. However, the precise role of ST2 in gastric cancer angiogenesis remains incompletely elucidated. We observed a significant correlation between high expression of ST2 in gastric cancer tissues and poor prognosis, along with various clinicopathological features. In vitro experiments demonstrated that the IL-33/ ST2 axis activates the PI3K/AKT/NF-κB signaling pathway through TRAF6, thereby promoting VEGFA-mediated tumor angiogenesis; meanwhile sST2 acts as a decoy receptor to regulate the IL-33/ST2L axis. Consistent findings were also observed in subcutaneous xenograft tumor models in nude mice. Furthermore, we investigated the molecular mechanism by which IL-33 promotes ST2L expression in GC cells via upregulation of transcription factors YY1 and GATA2 through intracellular signaling pathways.

Design, Synthesis, and Biological Evaluation of Some Novel Retinoid Derivatives

Background: As cancer stands as a significant global health concern, many heterocyclic compounds that are more effective in cancer cells than healthy cells are being investigated for their selective anticancer potentials. One such compound is fenretinide, a synthetic derivative of retinoic acid that has a broad spectrum of cytotoxic activity against primary tumor cells, cell lines, and/or xenografts of various cancers. In this context, bexarotene and its derivatives, synthesized from hybridization of the fenretinide, are expected to possess a potential anticancer activity. Objective: The objective of the present study was to investigate the synthesis of novel amid-derived and bexarotene-based compounds, as well as to assess their cytotoxic effects in different cancer cell lines. Methods: This study involved the synthesis of twelve novel retinoid derivatives (6-17) in a six-step process. The cytotoxic activities of these compounds were assessed against various cancer cell lines, such as A549 (human lung carcinoma), HeLa (human cervical cancer), MCF7 (human breast adenocarcinoma), and WiDr (human colon adenocarcinoma). The chemical structures of these compounds were elucidated through their elemental analysis, mass spectrometry (ESI+, ESI-), as well as 1H-NMR and 13C-NMR spectroscopic data. Results: The obtained cell toxicity results indicated that compounds 6, 8, 11, 12, 13, 14, and 17 were found to exhibit the strongest cytotoxic activity in above mentioned cancer cell lines. The IC50 values for active compounds, 11 and 12, were determined as 2.38μM and 2.29μM, respectively. Remarkably, these compounds displayed higher cytotoxic activity in the WiDr cell line related to positive control, camptothecin (CPT). Moreover, compounds 14 and 17 demonstrated very similar level of cytotoxic activity to CPT, indicating their potential for antitumoral applications upon further studies. Conclusion: While compounds 11, 12, 14, and 17 indicated a very comparable anticancer activity to CPT, compounds 6, 8, 11 and 12 showed more selective anticancer effect against cancer cells than noncancerous cells. In accordance with the findings of the present study, they can be evaluated as primary candidates for further studies, specifically as RXRα-targeted anticancer agents.

Downregulation of C1R promotes hepatocellular carcinoma development by activating HIF-1α-regulated glycolysis.

C1R has been identified to have a distinct function in cutaneous squamous cell carcinoma that goes beyond its role in the complement system. However, it is currently unknown whether C1R is involved in the progression of hepatocellular carcinoma (HCC). HCC tissues were used to examine C1R expression in relation to clinical and pathological factors. Malignant characteristics of HCC cells were assessed through in vitro and in vivo experiments. The mechanism underlying the role of C1R in HCC was explored through RNA-seq, methylation-specific PCR, immuno-precipitation, and dual-luciferase reporter assays. This study found that the expression of C1R decreased as the malignancy of HCC increased and was associated with poor prognosis. C1R promoter was highly methylated through DNMT1 and DNMT3a, resulting in a decrease in C1R expression. Downregulation of C1R expression resulted in heightened malignant characteristics of HCC cells through the activation of HIF-1α-mediated glycolysis. Additionally, decreased C1R expression was found to promote xenograft tumor formation. We found that C-reactive protein (CRP) binds to C1R, and the free CRP activates the NF-κB signaling pathway, which in turn boosts the expression of HIF-1α. This increase in HIF-1α leads to higher glycolysis levels, ultimately promoting aggressive behavior in HCC. Methylation of the C1R promoter region results in the downregulation of C1R expression in HCC. C1R inhibits aggressive behavior in HCC in vitro and in vivo by inhibiting HIF-1α-regulated glycolysis. These findings indicate that C1R acts as a tumor suppressor gene during HCC progression, opening up new possibilities for innovative therapeutic approaches.

Antitumor activities of anti‑CD44 monoclonal antibodies in mouse xenograft models of esophageal cancer.

CD44 is a type I transmembrane glycoprotein associated with poor prognosis in various solid tumors. Since CD44 plays a critical role in tumor development by regulating cell adhesion, survival, proliferation and stemness, it has been considered a target for tumor therapy. Anti‑CD44 monoclonal antibodies (mAbs) have been developed and applied to antibody‑drug conjugates and chimeric antigen receptor‑T cell therapy. Anti-pan‑CD44 mAbs, C44Mab‑5 and C44Mab‑46, which recognize both CD44 standard (CD44s) and variant isoforms were previously developed. The present study generated a mouse IgG2a version of the anti‑pan‑CD44 mAbs (5‑mG2a and C44Mab‑46‑mG2a) to evaluate the antitumor activities against CD44‑positive cells. Both 5‑mG2a and C44Mab‑46‑mG2a recognized CD44s‑overexpressed CHO‑K1 (CHO/CD44s) cells and esophageal tumor cell line (KYSE770) in flow cytometry. Furthermore, both 5‑mG2a and C44Mab‑46‑mG2a could activate effector cells in the presence of CHO/CD44s cells and exhibited complement-dependent cytotoxicity against both CHO/CD44s and KYSE770 cells. Furthermore, the administration of 5‑mG2a and C44Mab‑46‑mG2a significantly suppressed CHO/CD44s and KYSE770 xenograft tumor development compared with the control mouse IgG2a. These results indicate that 5‑mG2a and C44Mab‑46‑mG2a could exert antitumor activities against CD44‑positive cancers and be a promising therapeutic regimen for tumors.

Circ_0081723 enhances cervical cancer progression and modulates CREBRF via sponging miR-545-3p.

CircularRNAs(circRNAs)havebeenconfirmedtobeanimportantmodulatorandtherapeutictargetofcervicalcancer(CC).Theaimofthisstudyistoexploretheroleandmechanismofcirc_0081723inCCprogression. Circ_0081723,microRNA-545-3p(miR-545-3p), and CREB3regulatoryfactor(CREBRF) levels were detected using quantitativereal-timePCR (qRT-PCR) assay. CREBRF, ki-67,Bcl-2 related X protein (Bax), andE-cadherinexpression levels were determined using western blot (WB) and immunohistochemistry (IHC) assays. Cell proliferation was assessed using Cell Counting Kit-8 (CCK-8), cell colony formation, and 5-ethynyl-2'-deoxyuridine (EdU) assays. Flowcytometry was used to measurecellapoptosis. Cell migration and invasion were examined using Transwellassay. Interaction between miR-545-3p and circ_0081723 or CREBRF was verified using dual-luciferasereporterassay and RNAimmunoprecipitation (RIP) assays. The biological role of circ_0081723 on CC growth was examined using the xenograft tumor model in vivo. Circ_0081723 and CREBRF were increased, and miR-545-3p was decreased in CC tissues and cells. Circ_0081723 silencing suppressedCCcellgrowthandmotilitywhereasboostedCCcellapoptosis.Besides,circ_0081723actedasamolecularspongeformiR-545-3p,andcirc_0081723knockdown-inducedeffectswerelargelyreversedbymiR-545-3pdownregulationinCCcells.Moreover,miR-545-3prepressedCCprogressionbytargetingCREBRF.Circ_0081723absenceblockedxenografttumorgrowthinvivo. Circ_0081723stimulatedCCcellmalignantbehaviorsbyregulatingthe miR-545-3p/CREBRFpathway,providingapossiblecircRNA-targetedtherapyforCC.

Neuronatin Promotes the Progression of Non-small Cell Lung Cancer by Activating the NF-κB Signaling.

Understanding the regulatory mechanisms involving neuronatin (NNAT) in non-small cell lung cancer (NSCLC) is an ongoing challenge. This study aimed to elucidate the impact of NNAT knockdown on NSCLC by employing both in vitro and in vivo approaches. To investigate the role of NNAT, its expression was silenced in NSCLC cell lines A549 and H226. Subsequently, various parameters, including cell proliferation, invasion, migration, and apoptosis, were assessed. Additionally, cell-derived xenograft models were established to evaluate the effect of NNAT knockdown on tumor growth. The expression of key molecules, including cyclin D1, B-cell leukemia/lymphoma 2 (Bcl-2), p65, matrix metalloproteinase (MMP) 2, and nerve growth factor (NGF) were examined both in vitro and in vivo. Nerve fiber density within tumor tissues was analyzed using silver staining. Upon NNAT knockdown, a remarkable reduction in NSCLC cell proliferation, invasion, and migration was observed, accompanied by elevated levels of apoptosis. Furthermore, the expression of cyclin D1, Bcl-2, MMP2, and phosphorylated p65 (p-p65) showed significant downregulation. In vivo, NNAT knockdown led to substantial inhibition of tumor growth and a concurrent decrease in cyclinD1, Bcl-2, MMP2, and p-p65 expression within tumor tissues. Importantly, NNAT knockdown also led to a decrease in nerve fiber density and downregulation of NGF expression within the xenograft tumor tissues. Collectively, these findings suggest that neuronatin plays a pivotal role in driving NSCLC progression, potentially through the activation of the nuclear factor-kappa B signaling cascade. Additionally, neuronatin may contribute to the modulation of tumor microenvironment innervation in NSCLC. Targeting neuronatin inhibition emerges as a promising strategy for potential anti-NSCLC therapeutic intervention.

CircVIRMA enhances cell malignant behavior by governing the miR-452-5p/CREBRF pathway in cervical cancer.

Our current study aimed to investigate the role and mechanism of circVIRMA in cervical cancer (CC) progression. CircVIRMA, microRNA-452-5p (miR-452-5p) and CREB3 regulatory factor (CREBRF) mRNA levels were examined in CC via quantitative real-time PCR (qRT-PCR). The protein level of CREBRF in CC was checked by Western blot. Cell Counting Kit-8 (CCK-8), colony formation, 5-Ethynyl-2'-deoxyuridine (EdU) staining, cell cycle, flow cytometry and transwell assays were conducted to estimate the effects of circVIRMA on malignant phenotypes of CC tumors. Western blot was used to measure related marker protein levels. The interaction between miR-452-5p and circVIRMA or CREBRF was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays. Xenograft assay was used to assess the effect of circVIRMA on tumor growth in vivo. Immunohistochemistry (IHC) assay was performed to detect Ki-67 expression in tissues of mice. CircVIRMA and CREBRF levels were upregulated, while miR-452-5p was downregulated in CC tissues and cells. CircVIRMA silencing restrained CC cell proliferation, migration and invasion whereas induced apoptosis in vitro. In addition circVIRMA knockdown markedly attenuated xenograft tumor growth in vivo. circVIRMA was an efficient molecular sponge for miR-452-5p, and negatively regulated miR-452-5p expression. circVIRMA regulated CREBRF expression to modulate CC progression via miR-452-5p. MiR-452-5p downregulation reversed the effects of circVIRMA knockdown on CC progression. MiR-452-5p directly targeted CREBRF, and CREBRF overexpression partly restored the impact of miR-452-5p mimics on CC progression. circVIRMA mediated CC progression via regulating miR-452-5p/CREBRF axis, providing a novel therapeutic target for CC treatment.

Chondroitin polymerizing factor (CHPF) promotes the progression of colorectal cancer through ASB2-mediated ubiquitylation of SMAD9.

Chondroitin polymerizing factor (CHPF) has been reported to play a pivotal role in the progression of multiple cancers, however, the relationship between CHPF and colorectal cancer (CRC) progression has not been fully understood. The current study revealed that CHPF expression was upregulated in patients with CRC and correlated with an unfavorable prognosis. Also, CHPF knockdown effectively suppressed the viability and mobility of CRC cells and the growth of xenograft tumors. Additionally, SMAD9 was identified as a downstream target of CHPF. SMAD9 knockdown successfully abrogated the promotion of CHPF overexpression in CRC progression, indicating that CHPF regulated the development of CRC through SMAD9. Mechanistically, SMAD9 is ubiquitinated by ASB2, and the regulatory effect of CHPF on SMAD9 activity was exerted via its mediation of ASB2. Collectively, CHPF functioned as a promising prognostic biomarker and tumor-promoter of CRC by regulating the ASB2-mediated ubiquitination of SMAD9.

Mechanism of HOXA10 in nasopharyngeal carcinoma cell proliferation through the PTPRG-AS1/USP1 axis.

Nasopharyngeal carcinoma (NPC) is an epithelial carcinoma arising from the nasopharyngeal mucosal lining. The present study sought to analyze the mechanism by which homeobox A10 (HOXA10) affects NPC cell proliferation. The expression levels of HOXA10/long noncoding RNA (lncRNA) PTPRG antisense RNA 1 (PTPRG-AS1)/ubiquitin-specific peptidase 1 (USP1) in NPC tissues and cells were determined. Cell proliferation was evaluated. The enrichment of HOXA10 on the PTPRG-AS1 promoter was determined. The binding of PTPRG-AS1, HuR, and USP1 to each other was analyzed via RNA immunoprecipitation. USP1 mRNA stability was determined after actinomycin D treatment. The role of the PTPRG-AS1/USP1 axis in NPC cell proliferation was analyzed in combined experiments. The role of HOXA10 in vivo was confirmed in xenograft tumor models. The results revealed that HOXA10 was overexpressed in NPC. HOXA10 downregulation reduced NPC cell proliferation. PTPRG-AS1 and USP1 were upregulated in NPC. HOXA10 bound to the PTPRG-AS1 promoter to increase PTPRG-AS1 expression, and the binding of PTPRG-AS1 to HuR increased USP1 expression. PTPRG-AS1 or USP1 overexpression attenuated the inhibitory effects of HOXA10 downregulation on NPC cell proliferation. HOXA10 downregulation inhibited in vivo NPC proliferation through the PTPRG-AS1/USP1 axis. In conclusion, HOXA10 facilitates NPC cell proliferation in vitro and in vivo through the PTPRG-AS1/USP1 axis.