Astaxanthin induces autophagy and apoptosis in murine melanoma B16F10-Nex2 cells and exhibits antitumor activity in vivo

Countless efforts have been made to prevent and suppress the formation and spread of melanoma. Natural astaxanthin (AST; extracted from the alga Haematococcus pluvialis) showed an antitumor effect on various cancer cell lines due to its interaction with the cell membrane. This study aimed to characterize the antitumor effect of AST against B16F10-Nex2 murine melanoma cells using cell viability assay and evaluate its mechanism of action using electron microscopy, western blotting analysis, terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, and mitochondrial membrane potential determination. Astaxanthin exhibited a significant cytotoxic effect in murine melanoma cells with features of apoptosis and autophagy. Astaxanthin also decreased cell migration and invasion in vitro assays at subtoxic concentrations. In addition, assays were conducted in metastatic cancer models in mice where AST significantly decreased the development of pulmonary nodules. In conclusion, AST has cytotoxic effect in melanoma cells and inhibits cell migration and invasion, indicating a promising use in cancer treatment.

Fibroblast-Derived Lysyl Oxidase Increases Oxidative Phosphorylation and Stemness in Cholangiocarcinoma

BACKGROUND & AIMS

Metabolic and transcriptional programs respond to extracellular matrix-derived cues in complex environments, such as the tumor microenvironment. Here, we demonstrate how lysyl oxidase (LOX), a known factor in collagen crosslinking, contributes to the development and progression of cholangiocarcinoma (CCA).

METHODS

Transcriptomes of 209 human CCA tumors, 143 surrounding tissues, and single-cell data from 30 patients were analyzed. The recombinant protein and a small molecule inhibitor of the LOX activity were used on primary patient-derived CCA cultures to establish the role of LOX in migration, proliferation, colony formation, metabolic fitness, and the LOX interactome. The oncogenic role of LOX was further investigated by RNAscope and in vivo using the AKT/NICD genetically engineered murine CCA model.

RESULTS

We traced LOX expression to hepatic stellate cells and specifically hepatic stellate cell-derived inflammatory cancer-associated fibroblasts and found that cancer-associated fibroblast-driven LOX increases oxidative phosphorylation and metabolic fitness of CCA, and regulates mitochondrial function through transcription factor A, mitochondrial. Inhibiting LOX activity in vivo impedes CCA development and progression. Our work highlights that LOX alters tumor microenvironment-directed transcriptional reprogramming of CCA cells by facilitating the expression of the oxidative phosphorylation pathway and by increasing stemness and mobility.

CONCLUSIONS

Increased LOX is driven by stromal inflammatory cancer-associated fibroblasts and correlates with diminished survival of patients with CCA. Modulating the LOX activity can serve as a novel tumor microenvironment-directed therapeutic strategy in bile duct pathologies.

USP40 promotes hepatocellular carcinoma progression through a YAP/USP40 positive feedback loop

Yes-associated protein (YAP) is an essential driver of hepatocellular carcinoma (HCC) progression and the ubiquitin-proteasome system controls its abundance. However, the role of ubiquitin-specific protease 40 (USP40) in YAP stability remains unclear. Here, USP40 was first identified as a novel regulator of YAP abundance and its target genes in HCC cells. USP40 interacted with YAP to remove the lysine 48 (K48)-linked polyubiquitination of YAP at K252 and K315 sites, thereby maintaining YAP stability. USP40 facilitated the proliferation, colony formation, migration and spheroid formation of HCC cells in vitro and promoted HCC growth in vivo in a YAP-dependent manner. In turn, YAP transcriptionally activated USP40 expression in HCC cells. RNA sequencing analysis showed that about 37% of USP40-regulated genes overlapped with YAP-regulated genes. Interestingly, stiffness-induced USP40 upregulation was abolished by YAP knockdown, and USP40 knockdown attenuated stiffness-induced YAP accumulation in HCC cells. Clinical data demonstrated that USP40 was positively associated with YAP expression in HCC tissues and its high expression indicated a poor prognosis. In conclusion, the USP40/YAP positive feedback loop contributes to HCC progression, suggesting that USP40 may be a promising drug target for anti-HCC.

Activation of the FOXM1/ASF1B/PRDX3 axis confers hyperproliferative and antioxidative stress reactivity to gastric cancer

Nucleosome assembly during DNA replication is dependent on histone chaperones. Recent studies suggest that dysregulated histone chaperones contribute to cancer progression, including gastric cancer (GC). Further studies are required to explore the prognostic and therapeutic implications of histone chaperones and their mechanisms of action in GC progression. Here we identified histone chaperone ASF1B as a potential biomarker for GC proliferation and prognosis. ASF1B was significantly upregulated in GC, which was associated with poor prognosis. In vitro and in vivo experiments demonstrated that the inhibition of ASF1B suppressed the malignant characteristics of GC, while overexpression of ASF1B had the opposite effect. Mechanistically, transcription factor FOXM1 directly bound to the ASF1B-promoter region, thereby regulating its transcription. Treatment with thiostrepton, a FOXM1 inhibitor, not only suppressed ASF1B expression, but also inhibited GC progression. Furthermore, ASF1B regulated the mitochondrial protein peroxiredoxin 3 (PRDX3) transcription in a FOXM1-dependent manner. The crucial role of ASF1B-regulated PRDX3 in GC cell proliferation and oxidative stress balance was also elucidated. In summary, our study suggests that the FOXM1-ASF1B-PRDX3 axis is a potential therapeutic target for treating GC.

Ripe papaya pectins inhibit the proliferation of colon cancer spheroids and the formation of chemically induced aberrant crypts in rats colons

Pectins are a class of soluble polysaccharides that can have anticancer properties through several mechanisms. This study aimed to characterize the molecular structure of water-soluble fractions (WSF) derived from ripe and unripe papayas and assess their biological effects in two models: the 3D colon cancer spheroids to measure cell viability and cytotoxicity, and the in vivo model to investigate the inhibition of preneoplastic lesions in rats. WSF yield was slightly higher in ripe papaya, and both samples mainly consisted of pectin. Both pectins inhibited the growth of colon cancer HT29 and HCT116 spheroids. Unripe pectin disturbed HT29/NIH3T3 spheroid formation, decreased HCT116 spheroid viability, and increased spheroid cytotoxicity. Ripe pectin had a more substantial effect on the reduction of spheroid viability for HT29 spheroids. Furthermore, in vivo experiments on a rat model revealed a decrease in aberrant crypt foci (ACF) formation for both pectins and increased apoptosis in colonocytes for ripe papaya pectins. The results suggest potential anticancer properties of papaya pectin, with ripe pectin showing a higher potency.

FTO regulates osteoclast development by modulating the proliferation and apoptosis of osteoclast precursors in inflammatory conditions

Periodontitis is an oral inflammatory disease that causes alveolar bone destruction by activating osteoclast. FTO, a crucial demethylase of N6-methyladenosine(m6A), exerts essential function in maintaining bone homeostasis. However, the effects of FTO on periodontitis-related bone destruction remain unknown. To investigate its role in inflammatory osteoclastogenesis, we overexpressed FTO in osteoclast precursor cells; RNA-seq revealed that differentially expressed genes were mainly enriched in cell cycle, DNA replication, DNA damage response and apoptosis in FTO overexpression cells during RANKL and LPS-stimulated osteoclast differentiation. FTO overexpression upregulated the expression of S phase-related proteins (Cyclin A2, CDK2), and decreased the expression of DNA damage related proteins in osteoclast precursor cells. FTO promoted cell proliferation demonstrated by EdU and CCK8 assay, and reduced apoptotic rate and the expression of apoptosis-related proteins in osteoclast precursor cell. Conversely, FTO inhibitor FB23-2 produced the reverse effect. Mechanistically, FTO overexpression promoted the stability of CyclinA2 and CDK2 mRNA. These results were consistent in m6A binding protein YTHDF2 knockdown cells. Moreover, FB23-2 suppressed osteoclast-related gene expression, osteoclast formation and bone resorption ability. Treatment of FB23-2 reduced the alveolar bone loss in mice of experimental periodontitis. Collectively, our findings revealed that FTO enhanced the mRNA stability and expression of Cyclin A2, CDK2 in a YTHDF2-dependent manner in osteoclast precursor cells, promoted cell proliferation and inhibited cell apoptosis. FB23-2 reduced the formation of osteoclasts, resulted in alleviating the bone destruction in periodontitis mice. These findings indicated that FTO might be the potential target of the treatment of bone loss in periodontitis.

ING3 inhibits the malignant progression of lung adenocarcinoma by negatively regulating ITGB4 expression to inactivate Src/FAK signaling

Lung adenocarcinoma (LUAD) is the most commonly diagnosed subtype of lung cancer worldwide. Inhibitor of growth 3 (ING3) serves as a tumor suppressor in many cancers. This study aimed to elucidate the role of ING3 in the progression of LUAD and investigate the underlying mechanism related to integrin β4 (ITGB4) and Src/focal adhesion kinase (FAK) signaling. ING3 expression in LUAD tissues and the correlation between ING3 expression and prognosis were analyzed by bioinformatics databases. After evaluating ING3 expression in LUAD cells, ING3 was overexpressed to assess the proliferation, cell cycle arrest, migration and invasion of LUAD cells. Then, ITGB4 was upregulated to observe the changes of malignant activities in ING3-overexpressed LUAD cells. The transplantation tumor model of NCI-H1975 cells in nude mice was established to analyze the antineoplastic effect of ING3 upregulation in vivo. Downregulated ING3 expression was observed in LUAD tissues and cells and lower ING3 expression predicated the poor prognosis. ING3 upregulation restrained the proliferation, migration, invasion and induced the cell cycle arrest of NCI-H1975 cells. Additionally, ITGB4 expression was negatively correlated with ING3 expression in LUAD tissue. ING3 led to reduced expression of ITGB4, Src and p-FAK. Moreover, ITGB4 overexpression alleviated the effects of ING3 upregulation on the malignant biological properties of LUAD cells. It could be also found that ING3 upregulation limited the tumor volume, decreased the expression of ITGB4, Src and p-FAK, which was restored by ITGB4 overexpression. Collectively, ING3 inhibited the malignant progression of LUAD by negatively regulating ITGB4 expression to inactivate Src/FAK signaling.

Baicalein targets STMN1 to inhibit the progression of nasopharyngeal carcinoma via regulating the Wnt/β-catenin pathway

BACKGROUNDS

Nasopharyngeal carcinoma is a common malignancy in the head and neck. Baicalein has been reported to exert the anticancer effects on various cancers. In this study, our aim was to explore the function of baicalein in the development of nasopharyngeal carcinoma and further investigate the potential underlying mechanisms.

METHODS

Cell Counting Kit (CCK)-8 assay, EdU assay, sphere formation assay, flow cytometry, and transwell invasion assay were conducted to determine cell proliferation, stemness, apoptosis, and invasion, respectively. Western blot was performed to examine the protein levels of PCNA, MMP9, STMN1, β-catenin, and Wnt3A. The mRNA level of STMN1 was assessed using real-time quantitative polymerase chain reaction (RT-qPCR). Xenograft tumor model was carried out to evaluate the effects of baicalein on tumor growth in vivo. Immunohistochemistry (IHC) assay was used to detect the levels of PCNA, MMP9, and STMN1 in tumor tissues from mice.

RESULTS

Baicalein significantly induced cell apoptosis and impeded cell proliferation, invasion, and stemness of nasopharyngeal carcinoma cells. STMN1 was highly expressed in nasopharyngeal carcinoma, and baicalein could directly downregulate STMN1 expression. STMN1 knockdown hampered the progression of nasopharyngeal carcinoma cells. Moreover, the effects of baicalein on cell proliferation, stemness, invasion, and apoptosis in nasopharyngeal carcinoma cells were harbored by STMN1 overexpression. Baicalein regulated STMN1 to inhibit the activation of the Wnt/β-catenin pathway. SKL2001, an agonist of the Wnt/β-catenin pathway, could reverse the effects of STMN1 knockdown on the progression of nasopharyngeal carcinoma. In addition, baicalein markedly impeded tumor growth in vivo.

CONCLUSION

Baicalein regulated the STMN1/Wnt/β-catenin pathway to restrain the development of nasopharyngeal carcinoma.

PRDX2 regulates stemness contributing to cisplatin resistance and metastasis in bladder cancer

BACKGROUND

Cisplatin (CDDP)-based chemotherapy has emerged as the primary treatment for muscle-invasive bladder cancer and metastatic bladder cancer. Nevertheless, a significant proportion of patients experience rapidly developed chemoresistance, leading to treatment ineffectiveness. Existing evidence suggests that chemoresistance is governed by various factors, including tumor stem cells, epithelial mesenchymal transition, and reactive oxygen species (ROS). However, limited research has been conducted on the role of PRDX2, a crucial ROS scavenger, in the modulation of chemoresistance in bladder cancer.

METHODS

Cisplatin-resistant cell lines were established using the concentration gradient overlay method, and differentially expressed genes in resistant cells were screened through RNA sequencing. The expression of PRDX2 in cells and tissues was assessed using RT-qPCR, Western Blot, and immunohistochemistry. The expression of PRDX2 in bladder cancer and adjacent tissues was evaluated using a bladder cancer tissue microarray. Furthermore, the impact of PRDX2 knockdown on tumor formation and metastasis was investigated in vivo by applying subcutaneous tumor xenografts tail vein metastasis assays.

RESULTS

We demonstrated that PRDX2 is significantly upregulated in bladder tumors and cisplatin-resistant bladder tumor cell lines. Overexpression of PRDX2 can promote tumor proliferation, migration, and invasion both in vitro and in vivo. We have found that knockdown of PRDX2 expression can effectively reverse cell resistance to cisplatin. Mechanistically, our findings suggest that PRDX2 is involved in regulating tumor stemness and epithelial-mesenchymal transition (EMT). Knockdown of PRDX2 affects the PI3K-AKT and mTOR signaling pathways, thereby influencing tumor stemness and EMT, ultimately impacting the chemotherapy resistance of the tumor.

CONCLUSIONS

This study provides a new insight into the regulation of chemotherapy resistance in bladder cancer by PRDX2. Targeting PRDX2 can serve as a potent therapeutic target for chemotherapy resistance.

Novel chiral matrine derivatives as potential antitumor agents: Design, synthesis and biological evaluation

Since the thalidomide incident, research on chiral drugs has escalated immensely. Differences in drug configuration can lead to significant variations in therapeutic efficacy. Matrine, a natural product esteemed for its low toxicity and high water solubility, has garnered significant attention in research endeavors. Nonetheless, its precise target has proven elusive. In this study, we designed and synthesized a novel chiral matrine derivative. Their cytotoxicity against three types of tumor cells was assessed. Comparing the newly synthesized derivatives to the parent matrine, most compounds exhibited significantly enhanced inhibitory effects on cancer cells. Among them, Q12 exhibited the highest activity, with IC50 values of 8.31 μM against rat glioma cells C6, 6.3 μM against human liver cancer cells HepG2 and 7.14 μM against human gastric cancer cells HGC-27, meanwhile showing low toxicity. Based on IC50 values, we constructed a preliminary structure-activity relationship (SAR). Compound Q12 significantly suppressed the cloning and migration of HepG2 cells. Further mechanistic studies indicated that Q12 inhibited Topo I in HepG2 cells, leading to DNA damage, induction of G0/G1 cell cycle arrest and ultimately causing apoptosis. The molecular docking experiments provided a rational binding mode of Q12 with the Topo I-DNA complex. In vivo, experiments demonstrated that Q12 exhibited a higher tumor growth inhibition rate (TGI) compared to the positive control drug Lenvatinib, while maintaining good safety. In summary, it suggests that Topo I might be a potential target for matrine and Q12 represents a promising candidate for cancer treatment.

LRP8 promotes tumorigenesis in ovarian cancer through inhibiting p53 signaling

Ovarian cancer (OC) is the most lethal gynecological malignancy with a high mortality rate. Low-density lipoprotein (LDL) receptor-related protein 8 (LRP8) is a cell membrane receptor belonging LDL receptor family and is involved in several tumor progressions. However, there is limited understanding of how LRP8 mediates OC development. LRP8 expression level was identified in human OC tissues and cells using immunohistochemical staining and quantitative polymerase chain reaction assays, respectively. Functions of LRP8 in OC progression were evaluated by Celigo cell counting, wound healing, transwell and flow cytometry assays, and the xenograft models. The human phospho-kinase array analysis was used for screening potential signaling involved in OC development. We observed that LRP8 was overexpressed in OC tissues, and high expression of LRP8 was associated with poor prognosis of OC patients. Functionally, LRP8 knockdown remarkably reduced proliferation and migration of OC cells, and induced apoptosis and S phase cycle arrest. LRP8 deficiency attenuated in vivo tumor growth of OC cells. Moreover, the addition of p53 inhibitor partially reversed the effects of LRP8 knockdown on OC cell proliferation and apoptosis, indicating the involvement of p53 signaling in LRP8-mediated OC progression. This study confirmed that LRP8/p53 axis contributed to OC progression, which might serve as a novel potential therapeutic target for OC patients.

Alkaloids from the stems of Fissistigma maclurei Merr. inhibit the proliferation of synoviocytes

Two new aporphine-derived alkaloids, aporaloids C and D (1 and 2), along with eight known biogenetically related alkaloids (3-10) were isolated from the stems of Fissistigma maclurei Merr. Their structures were elucidated by detailed analysis of NMR, HRESIMS, MS, IR, UV and Optical rotations data. Compounds 1 and 2 represent a rare example of N-methylol aporphine-derived alkaloids from natural sources. The inhibitory effect of all compounds on the proliferation of primary synovial cells was evaluated. Compound 3 showed potent inhibitory effect on the proliferation of synoviocytes with an IC50 value of 4.8 μM. Compounds 1, 2, 6-9 and 10 exhibited moderate inhibitory activity on synoviocytes, with IC50 values of 36.8, 37.1, 31.2 μM, 32.5, 36.3, 36.8 and 18.2 μM, respectively.

Synthesis, docking study, and antitumor evaluation of benzamides and oxadiazole derivatives of 3-phenoxybenzoic acid as VEGFR-2 inhibitors

Current chemotherapeutic agents have several limitations, including lack of selectivity, the development of undesirable side effects, and chemoresistance. As a result, there is an unmet need for the development of novel small molecules with minimal side effects and the ability to specifically target tumor cells. A new series of 3-phenoxybenzoic acid derivatives, including 1,3,4-oxadiazole derivatives (4a-d) and benzamides derivatives (5a-e) were synthesized; their chemical structures were confirmed by Fourier-transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR), 13C NMR, and mass spectra; and various physicochemical properties were determined. The antiproliferative activities of the new derivatives were evaluated by means of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Three compounds (4b, 4c, and 4d) exhibited cytotoxicity against two of the three cell lines tested, five compounds (3, 4a, 5a, 5b, and 5e) were toxic to one cell line, while two compounds (5c and 5d) were not cytotoxic to any of the three cell lines tested in the current study. Based on docking scores, MTT assay findings, and vascular endothelial growth factor receptor 2 (VEGFR-2) kinase activity data, Compound 4d was selected for further biological investigation. Flow cytometry was used to determine the mode of cell death (apoptosis vs. necrosis) and the effect on cell cycle progression. Compound 4d arrested HepG2 hepatocellular carcinoma cells in the G2/M phase and activated both the intrinsic and extrinsic apoptosis pathways. In conclusion, Compound 4d has shown promising results for future research as a potent VEGFR-2 tyrosine kinase inhibitor.

Alterations in Immune Responses Are Associated with Dysfunctional Intracellular Signaling in Peripheral Blood Mononuclear Cells of Men and Women with Mild Cognitive Impairment and Alzheimer's disease

Deficits in the neuroendocrine-immune network in the periphery associated with the onset and progression of mild cognitive impairment (MCI) and Alzheimer's disease (AD) have not been extensively studied. The present study correlatively examines the association between cell-mediated immune responses, stress hormones, amyloid precursor protein (APP) expression, peripheral blood mononuclear cells (PBMC), and intracellular signaling molecules in the pathophysiology of MCI and AD compared to adults. Serum APP, lymphocyte proliferation, total cholinesterase (TChE), butyrylcholinesterase (BChE) activities, cytokines (IL-2, IFN-γ, IL-6, and TNF-α), and intracellular signaling molecules (p-ERK, p-CREB, and p-Akt) were measured in the PBMCs of adult, old, MCI, and AD men and women initially and after 3 years in the same population. An age- and disease-associated decline in mini-mental state examination (MMSE) scores and lymphocyte proliferation of MCI and AD men and women were observed. An age- and disease-related increase in serum APP, cortisol levels, and TChE activity were observed in men and women. Enhanced production of Th1 cytokine, IL-2, pro-inflammatory cytokines, and suppressed intracellular transcription factors may promote the inflammatory environment in MCI and AD patients. The expression of CREB and Akt was lower in MCI and AD men, while the expression of p-ERK was higher, and p-CREB was lower in MCI and AD women after 3 years. These results suggest that changes in specific intracellular signaling pathways may influence alterations in cell-mediated immunity to promote disease progression in MCI and AD patients.

KDM5B promotes metastasis and epithelial-mesenchymal transition via Wnt/β-catenin pathway in squamous cell carcinoma of the head and neck

Metastasis determines clinical management decision and restricts the therapeutic efficiency in patients with squamous cell carcinoma of the head and neck (SCCHN). Epigenetic factor KDM5B serves as an oncogene in multiple cancers. However, its role in SCCHN metastasis remains unclear. Our previous study showed that KDM5B is significantly elevated in SCCHN tissue and is positively correlated with metastasis and recurrence. KDM5B overexpression predicted a poor prognosis in both disease-free survival and overall survival, which served as an independent prognostic factor in SCCHN patients. This study further investigates the exact impact of KDM5B in metastasis of SCCHN. We found that KDM5B knockdown significantly inhibits the migration and invasion of SCCHN cells both in vitro and in vivo. On the contrary, forced expression of KDM5B leads to enhanced migration and invasion, accompanied by canonical alterations of epithelial-mesenchymal transition (EMT). Mechanism investigations demonstrated that KDM5B activates Wnt/β-catenin pathway, and inhibition of Wnt/β-catenin pathway via a small molecule inhibitor iCRT-14 partially reverses the enhanced migratory and invasive ability caused by KDM5B in SCCHN cells. Together, our data indicate that KDM5B promotes EMT and metastasis via Wnt/β-catenin pathway in SCCHN, suggesting that KDM5B may be a potential therapeutic target and prognosis biomarker in SCCHN.

Pigment epithelium‑derived factor inhibits proliferation, invasion and angiogenesis, and induces ferroptosis of extravillous trophoblasts by targeting Wnt‑β‑catenin/VEGF signaling in placenta accreta spectrum

Placenta accreta spectrum (PAS) is one of the most dangerous complications in obstetrics, which can lead to severe postpartum bleeding and shock, and even necessitate uterine removal. The abnormal migration and invasion of extravillous trophoblast cells (EVTs) and enhanced neovascularization occurring in an uncontrolled manner in time and space are closely related to the abnormal expression of pro‑angiogenic and anti‑angiogenic factors. The pigment epithelium‑derived factor (PEDF) is a multifunctional regulatory factor that participates in several important biological processes and is recognized as the most efficient inhibitor of angiogenesis. The present study aimed to explore the effects of PEDF on EVT phenotypes and the underlying mechanisms in PAS. HTR‑8/SVneo cells were transfected to overexpress or knock down PEDF. Cell proliferation and invasion were assessed using Cell Counting Kit‑8, 5‑ethynyl‑2'‑deoxyuridine and Transwell assays. In vitro angiogenesis was analyzed using tube formation assays. The degree of ferroptosis was assessed by evaluating the levels of lipid reactive oxygen species, total iron, Fe2+, malondialdehyde and reduced glutathione using commercial kits. The expression levels of biomarkers of ferroptosis, angiogenesis, cell proliferation and Wnt signaling were examined by western blotting. PEDF overexpression decreased the proliferation, invasion and angiogenesis, and induced ferroptosis of EVTs. Activation of Wnt signaling with BML‑284 and overexpression of vascular endothelial growth factor (VEGF) reversed the PEDF overexpression‑induced suppression of cell proliferation, invasion and tube formation. PEDF overexpression‑induced ferroptosis was also decreased by Wnt agonist treatment and VEGF overexpression. It was predicted that PEDF suppressed the proliferation, invasion and angiogenesis, and increased ferroptosis in EVTs by decreasing Wnt‑β‑catenin/VEGF signaling. The findings of the present study suggested a novel regulatory mechanism of the phenotypes of EVTs and PAS.

Norcantharidin inhibits the malignant progression of cervical cancer by inducing endoplasmic reticulum stress

The antitumor effect of norcantharidin (NCTD) has been widely reported. However, whether NCTD can inhibit cervical cancer remains unknown. In the present study, it was shown that NCTD inhibited the viability of cervical cancer cells and caused cell cycle arrest in a concentration‑dependent manner. Further analysis revealed that the NCTD‑induced reduction in cell viability could be reversed by the inhibitor of apoptosis z‑VAD‑FMK and by the inhibitor of endoplasmic reticulum (ER) stress, 4‑phenylbutyric acid (4‑PBA). Additionally, NCTD led to the accumulation of reactive oxygen species as well as a decrease in the mitochondrial membrane potential in cervical cancer cells, whereas 4‑PBA pre‑treatment attenuated these alterations. In addition, NCTD increased the expression of the apoptosis‑related proteins Bip, activating transcription factor (ATF) 4 and C/EBP homologous protein in a concentration‑dependent manner. Moreover, NCTD significantly increased the expression of the ER stress‑related signaling molecules protein kinase R‑like ER kinase, inositol‑requiring enzyme 1 and ATF6, but 4‑PBA abolished these effects. In vivo experiments showed that NCTD significantly inhibited the growth of subcutaneous tumors in mice. Additionally, the expression of ER stress‑related molecules and apoptosis‑related proteins increased significantly after NCTD treatment. In conclusion, NCTD induces apoptosis by activating ER stress and ultimately curtails the progression of cervical cancer.

Human papillomavirus-16 E6 activates the pentose phosphate pathway to promote cervical cancer cell proliferation by inhibiting G6PD lactylation

High-risk human papillomaviruses (HPVs) are the causative agents of cervical cancer. Here, we report that HPV16 E6E7 promotes cervical cancer cell proliferation by activating the pentose phosphate pathway (PPP). We found that HPV16 E6 activates the PPP primarily by increasing glucose-6-phosphate dehydrogenase (G6PD) enzyme activity. Mechanistically, HPV16 E6 promoted G6PD dimer formation by inhibiting its lactylation. Importantly, we suggest that G6PD K45 was lactylated during G6PD-mediated antioxidant stress. In primary human keratinocytes and an HPV-negative cervical cancer C33A cells line ectopically expressing HPV16 E6, the transduction of G6PD K45A (unable to be lactylated) increased GSH and NADPH levels and, correspondingly, decreasing ROS levels. Conversely, the re-expression of G6PD K45T (mimicking constitutive lactylation) in HPV16-positive SiHa cells line inhibited cell proliferation. In vivo, the inhibition of G6PD enzyme activity with 6-aminonicotinamide (6-An) or the re-expression of G6PD K45T inhibited tumor proliferation. In conclusion, we have revealed a novel mechanism of HPV oncoprotein-mediated malignant transformation. These findings might provide effective strategies for treating cervical and HPV-associated cancers.

Efficient assembly and anti-tumor evaluation of novel polycyclic [1,2-a]-fused indoles

Structurally diverse cyclopenta[4,5]pyrrolo[1,2-a]indoles heterocycles were smoothly constructed in good to excellent yields (up to 99 %) with excellent diastereoselectivities (>19:1 dr) through a novel and facile strategy based on BF3-catalyzed Friedel-Crafts alkylation/Aldol/Dehydrative cyclization cascade reaction. The anti-proliferative activity of these newly synthesized polycyclic indoles was screened, and all the functionalized reductive derivatives exhibited favorable anti-tumor activity. Notably, compound 4ae displayed the remarkable inhibitory activity against MCF-7 and HeLa cells with IC50 values of 4.62 μM and 7.71 μM, respectively. Mechanistically, the representative compound 4ae could effectively induce apoptosis of MCF-7 cells in crediting to up-regulate the relative expression of apoptotic protein BAX/Bcl-2, subsequently activate Pro-caspase 9 and cleave PARP, simultaneously block the cell cycle through down- and up-regulate the expression of cyclin B1 and p53, respectively. Moreover, compound 4ae also exhibited promising antineoplastic efficacy in subcutaneous MCF-7 xenograft mice which manifest significant shrunken tumors conspicuous nuclear apoptotic signal and minimal systemic toxicity. This strategy not only established a novel and efficient method for the assembly of structurally complex indole heterocycles, but also provided a series of compounds possessing attractive anti-cancer activity, which holds immense potential for future biomedical applications.

Anticancer effect of hUC-MSC-derived exosome-mediated delivery of PMO-miR-146b-5p in colorectal cancer

Antisense oligonucleotide (ASO) is a novel therapeutic platform for targeted cancer therapy. Previously, we have demonstrated that miR-146b-5p plays an important role in colorectal cancer progression. However, a safe and effective strategy for delivery of an ASO to its targeted RNA remains as a major hurdle in translational advances. Human umbilical cord mesenchymal cell (hUC-MSC)-derived exosomes were used as vehicles to deliver an anti-miR-146b-5p ASO (PMO-146b). PMO-146b was assembled onto the surface of exosomes (e) through covalent conjugation to an anchor peptide CP05 (P) that recognized an exosomal surface marker, CD63, forming a complex named ePPMO-146b. After ePPMO-146b treatment, cell proliferation, uptake ability, and migration assays were performed, and epithelial-mesenchymal transition progression was evaluated in vitro. A mouse xenograft model was used to determine the antitumor effect and distribution of ePPMO-146b in vivo. ePPMO-146b was taken up by SW620 cells and effectively inhibited cell proliferation and migration. The conjugate also exerted antitumor efficacy in a xenograft mouse model of colon cancer by systematic administration, where PPMO-146b was enriched in tumor tissue. Our study highlights the potential of hUC-MSC-derived exosomes anchored with PPMO-146b as a novel safe and effective approach for PMO backboned ASO delivery.

BILATERAL DIFFUSE UVEAL MELANOCYTIC PROLIFERATION MISTAKEN FOR NIVOLUMAB-INDUCED VOGT-KOYANAGI-HARADA DISEASE-LIKE SYNDROME

BACKGROUND/PURPOSE

To describe a case of bilateral diffuse uveal melanocytic proliferation (BDUMP) that was mistaken for nivolumab-induced Vogt-Koyanagi-Harada disease-like syndrome.

METHODS

We present the case of a 58-year-old white man with metastatic renal clear cell carcinoma for which he was palliatively treated with IV nivolumab immunotherapy. The patient developed subacute onset of blurry vision and gray spots in the visual fields of both eyes, macular subretinal fluid, thickening of the retinal pigment epithelium, and swollen optic nerve heads. Differential diagnosis included nivolumab-induced Vogt-Koyanagi-Harada disease-like syndrome, and the patient was initially treated with steroids, which gave no improvement. Investigation showed the development of dark-gray patches in the peripheral retina of both eyes and cataract, which prompted reevaluation of the diagnosis, deeming BDUMP most likely. The patient was successfully treated with plasmapheresis.

RESULTS

The initial presentation of the case was incorrectly diagnosed as nivolumab-induced Vogt-Koyanagi-Harada disease-like syndrome. On repeat studies of the patients' symptoms and imaging, we concluded we had missed signs of BDUMP.

CONCLUSION

The diagnosis BDUMP was missed in the first evaluation. We present this case to discuss the similarities and differences between this disease and nivolumab-induced Vogt-Koyanagi-Harada disease-like syndrome. More importantly, we want to highlight that reevaluation of the diagnosis on worsening of a disease was key in this unusual case.

FATP2 activates PI3K/Akt/mTOR pathway by inhibiting ATF3 and promotes the occurrence and development of bladder cancer

Bladder cancer (BLCA) is ranked among the main causes of mortality in male cancer patients, and research into targeted therapies guided by its genomics and molecular biology has been a prominent focus in BLCA studies. Fatty acid transporter protein 2 (FATP2), a member of the FATPs family,is a key contributor to the progression of cancers such as hepatocellular carcinomas and melanomas.However,its role in BLCA remains poorly understand. This study delved into the function of FATP2 in BLCA through a succession of experiments in vivo and in vitro, employing techniques as quantitative real-time polymerase chain reaction (qRT-PCR), RNA sequencing, transwell assays, immunofluorescence, western blot,and others to dissect its mechanistic actions. The findings revealed that an oncogenic function is executed by FATP2 in bladder cancer, significantly impacting the proliferation and migration capabilities, thereby affecting the prognosis of BLCA patients. Furthermore, A suppression that relies on both time and concentration of BLCA proliferation and migration, trigger of apoptosis, and blockage of the cell cycle at the G2/M phase were observed when the inhibitor of FATP2, Lipofermata, was applied. It was unveiled through subsequent investigations that ATF3 expression is indirectly promoted by Lipofermata through the inhibition of FATP2, ultimately inhibiting the signal transduction of the PI3K/Akt/mTOR pathway. This effect was also responsible for the inhibitory impact on BLCA proliferation. Therefore, FATP2 emerges as an auspicious and emerging molecular target with potential applications in precision therapy in BLCA.

METTL3 modification of circStk4 affects mouse glomerular messangial cell autophagy, proliferation and apotosis by regulating miR-133a-3p/C1 axis

OBJECTIVE

The study aimed to explore the impact of N6-methyladenosine (m6A) modification in circStk4 on glomerular mesangial cells (GMCs) autophagy, proliferation and apoptosis.

METHODS

The interactions between circStk4 and miR-133a-3p, miR-133a-3p and C1 were demonstrated through luciferase reporter assays. The circStk4 localization was analyzed using fluorescence in situ hybridization and nuclear/cytosol fractionation assays. Colorimetric assays, MeRIP-qPCR, and western blot (WB) were employed to confirm the m6A modification of circStk4 and identify the key methylation enzyme. RT-qPCR was conducted to determine the impact of METTL3 on the circStk4 RNA expression. Additionally, CCK-8, flow cytometry, transmission electron microscopy, immunofluorescence, WB and RT-qPCR were employed to investigate the effects of METTL3 or circStk4 on the proliferation, autophagy and apoptosis of GMCs. Enzyme-linked immunosorbent assay was utilized to assess the inflammatory factors.

RESULTS

m6A modifications were found in circStk4 and METTL3 was a key methylating enzyme. Furthermore, it was observed that circStk4 competitively bound miR-133a-3p and increased C1 levels. Silencing circStk4 resulted in decreased GMCs proliferation, increased autophagy and apoptosis, and reduced inflammation levels. Additionally, METTL3 played a role in inhibiting GMCs proliferation and promoting autophagy and apoptosis by regulating the circStk4 expression. On verifying the interplay between autophagy, proliferation and apoptosis, and found that the inhibition of autophagy led to an increase in cell proliferation and a decrease in apoptosis.

CONCLUSION

m6A modification of circStk4 mediated by METTL3 influenced circStk4 expression and impacted autophagy, proliferation and apoptosis in GMCs via the miR-133a-3p/C1 axis. This discovery introduces a novel therapeutic approach for CGN treatment.

Beauvericin, produced by Fusarium oxysporum inhibits bisphenol A-induced proliferation of human breast cancer cell line by regulating ERα/p38 pathway

Beauvericin (BEA) is a cyclic depsipeptide secondary metabolite of Fusarium species. It causes chemical hazards in food products and exists in an environment containing soil and various food types. On the other hand, the purified BEA has various biological activities and is regarded as a potential candidate for pharmaceutical research. This study was performed to assess the anti-proliferation activity of BEA against human breast cancer cells by regulating the estrogen receptor-alpha (ERα)/p38 pathway. TA and BA assays verified that BEA is a completed ER antagonist. Additionally, BEA suppressed cell proliferation in the anti-proliferation assay involving ER-positive human breast cancer cells co-treated with BPA and BEA. In respect to an anti-proliferation activity, the BPA-induced phosphorylation of p38 protein was inhibited in the presence of BEA. These results suggested that BEA exerts inhibitory potentials on endocrine disrupting effect and possibly acts as a natural therapeutic material for human estrogen hormonal health.

Bisphenol A promotes cell death in healthy respiratory system cells through inhibition of cell proliferation and induction of G2/M cell cycle arrest

Bisphenol A (BPA) is a substance that can harm the environment and human health by interfering with the normal functioning of the body's hormonal system. It is commonly found in various plastic-based products such as cosmetics, canned foods, beverage containers, and medical equipment and as well as it can also be absorbed by inhalation. There have been limited studies on the effects of BPA on lung fibroblasts, and it is still unclear how high levels of BPA can impact respiratory system cells, particularly the lungs and trachea. In this research, we aimed to investigate the cell cycle disruption potential of BPA on respiratory system cells by examining healthy trachea and lung cells together for the first time. The findings indicated that BPA exposure can alter the healthy cells' morphology, leading to reduced cellular viability that has been assessed by MTT and SRB assays. BPA treatment was able to activate caspase3 as expected, which could cause apoptosis in treated cells. Although the highest dose of BPA did not increase the apoptotic rate of rat trachea cells, it remarkably caused them to become necrotic (52.12%). In addition to quantifying the induction of apoptosis and necrosis by BPA, cell cycle profiles were also determined using flow cytometry. Thereby, BPA treatment unexpectedly inhibited the cell cycle's progression by causing G2/M cell cycle arrest in both lung and tracheal cells, which hindered cell proliferation. The findings of the study suggested that exposure to BPA could lead to serious respiratory problems, even respiratory tract cancers via alterations in the cell cycle.

Hsa_circ_0003356 suppresses gastric cancer progression via miR-556-5p/FKBP5 axis

BACKGROUND

CircRNAs are implicated in the tumorigenesis of various human cancers. This study aims to explore how circ_0003356 contributes to the development of gastric cancer (GC).

METHODS

Circ_0003356 expression was analyzed in GSE184882 dataset and validated in our cohort of GC patients and human GC cell lines. The correlations between circ_0003356 levels and prognostic parameters were analyzed. The contribution of circ_0003356 in GC cell malignant behaviors such as cell survival, apoptosis and invasion were investigated by circ_0003356 overexpression in GC cell lines. The downstream targets of circ_0003356 were predicted and verified in vitro and in vivo. The in vivo function of circ_0003356 was studied as well in a xenograft mouse model.

RESULTS

Circ_0003356 expressed at a low level in human GC tissues and cells, which was closely associated with poor outcome of GC patients. Circ_0003356 overexpression induced GC cell apoptosis while depressed the growing, migration and invasive abilities through miR-556-5p/FKBP5 axis. In vivo model showed retarded tumor growth when circ_0003356-overexpressed cells were inoculated.

CONCLUSION

Circ_0003356 is identified as a potential biomarker of the prognosis of human gastric cancer, and circ_0003356/miR-556-5p/FKBP5 axis could be a promising target in gastric cancer treatment.

DMC triggers MDA-MB-231 cells apoptosis via inhibiting protective autophagy and PI3K/AKT/mTOR pathway by enhancing ROS level

DMC, a kind of compound derived from the dry flower buds of Cleistocalyx operculatus, has been shown to inhibit the growth of various cancer cells, but research on triple-negative breast cancer cells remains scarce. To explore this issue, MDA-MB-231 cells were selected, and the results showed that DMC has strong proliferation inhibit effects on this kind of cells. The inhibit rate of 30 μM DMC incubated for 24 h was 56.25%, and 40.6% cells were arrested under the G2/M phase. The levels of pro-apoptosis protein Bax and active caspase-3, cleaved PARP and cell cycle related proteins, such as p21 and p27 increased, but apoptosis regulators, like Bcl-2, Cdc 2, Cyclin B1, and LC3 II decreased dramatically. In addition, DMC induced the accumulation of autophagosomes and autophagic substrates, and the combination of DMC with CQ promoted apoptosis of MDA-MB-231 cells, which suggested that DMC induced apoptosis partly by blocking autophagy flow. Moreover, the phosphorylation levels of phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), and its mechanistic target of rapamycin kinase (mTOR) were also decreased after 30 μM DMC incubating for 24 h. The proteins play a critical role in cell proliferation, apoptosis, and autophagy modulation. The inhibition of autophagy flow and PI3K/AKT/mTOR pathway could be reversed after being treated with ROS scavenger NAC. Altogether, the results of the present study suggest that DMC effectively induces apoptosis and growth inhibition in MDA-MB-231 cells through blocking autophagy flow and regulating the PI3K/AKT/mTOR pathway by increasing ROS level.

Nasopharyngeal carcinoma with non-squamous phenotype may be a variant of nasopharyngeal squamous cell carcinoma after inhibition of EGFR/PI3K/AKT/mTOR pathway

Nasopharyngeal carcinoma (NPC) is a cancerous tumor that develops in the nasopharynx epithelium and typically has squamous differentiation. The squamous phenotype is evident in immunohistochemistry, with diffuse nuclear positivity for p63 and p40. Nonetheless, a few NPCs have been identified by clinicopathological diagnosis that do not exhibit the squamous phenotype; these NPCs are currently referred to as non-squamous immunophenotype nasopharyngeal carcinomas (NSNPCs). In a previous work, we have revealed similarities between the histological appearance, etiology, and gene alterations of NSNPC and conventional NPC. According to ultrastructural findings, NSNPC still falls under the category of non-keratinized squamous cell carcinoma that is undifferentiated. NSNPC has an excellent prognosis and a low level of malignancy, according to a retrospective investigation. Based on prior research, we investigated the molecular mechanism of NSNPC not expressing the squamous phenotype and its biological behavior. IHC was used to determine the expression of EGFR, PI3K, AKT, p-AKT, mTOR, p-mTOR, Notch, STAT3 and p-STAT3 in a total of 20 NSNPC tissue samples and 20 classic NPC tissue samples. We obtained human NPC cell lines (CNE-2,5-8F) and used EGFR overexpression plasmid and shRNAs to transfect them. To find out whether mRNA and proteins were expressed in the cells, we used Western blotting and qRT-PCR. Cell biological behavior was discovered using the CCK-8 assay, cell migration assay, and cell invasion assay. EGFR, PI3K, p-AKT and p-mTOR proteins were lowly expressed in NSNPC tissues by immunohistochemistry, compared with classical NPC. In the classical NPC cell lines CNE-2 and 5-8F, overexpression EGFR can up-regulate the expression of p63 through the PI3K/AKT/mTOR pathway, and promote the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. At the same time, knockout of EGFR can down-regulate p63 expression through the PI3K/AKT/mTOR pathway, and inhibit the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. The lack of p63 expression in NSNPC was linked with the inhibition of the EGFR/PI3K/AKT/mTOR pathway, and NSNPC may be a variant of classical NPC.

Trps1 predicts poor prognosis in advanced high grade serous ovarian carcinoma

TRPS1 is aberrantly expressed in a variety of tumors, including breast, prostate, and gastric cancers, and is strongly associated with tumorigenesis or prognosis. However, the role of TRPS1 in high grade serous ovarian carcinoma (HGSC) is unknown. We investigated the relationship between TRPS1 expression and clinicopathology in HGSC patients. The tumor-related regulatory mechanisms of TRPS1 was explored through in vivo and vitro experiments. The results showed that TRPS1 was highly expressed in HGSC compared to normal tissues. It was also linked to the cell proliferation index Ki67 and poor prognosis. In vivo experiments showed that knockdown of TRPS1 could inhibit tumor growth. In vitro experiments, knockdown of TRPS1 inhibited the proliferation of ovarian cancer cells. TRPS1 exerted its regulatory role as a transcription factor, binding to the PSAT1 promoter and promoting the expression of PSAT1 gene. Meanwhile, PSAT1 was positively correlated with CCND1 expression. These results suggest that TRPS1 affects HGSC proliferation and cell cycle by regulating PSAT1 and thus CCND1 expression.

Artesunate-loaded solid lipid nanoparticles resist esophageal squamous cell carcinoma by inducing Ferroptosis through inhibiting the AKT/mTOR signaling

Esophageal squamous cell carcinoma (ESCC) is a severe malignancy with high incidence and mortality rate in China, while the application of standard chemotherapeutic drugs for ESCC meets the barriers of high toxicity and multiple drug resistance (MDR). In recent years, the anticancer effects of artesunate (ART), a Chinese medicine monomer have gained extensive attentions due to its characteristics of low toxicity, high potency, and reversal of MDR. In this study, we develop the artesunate-loaded solid lipid nanoparticles (SLNART) to overcome the poor water solubility and bioavailability of ART, further improving the efficiency of ART on ESCC treatment. Especially mentioned, SLNART is shown to present marked inhibitory effects on ESCC development based on the induction of ferroptosis by two pathways included upregulating TFR to increase Fe2+ ions and inhibiting the AKT/mTOR signaling to downregulate GPX4. Collectively, this study is the first to pave a promising approach for ESCC therapy based on a strategy of developing SLNART to induce ferroptosis by mediating Fe2+ ions and AKT/mTOR signaling.

MITF regulates the subcellular location of HIF1α through SUMOylation to promote the invasion and metastasis of daughter cells derived from polyploid giant cancer cells

High concentrations of cobalt chloride (CoCl2) can induce the formation of polyploid giant cancer cells (PGCCs) in various tumors, which can produce daughter cells with strong proliferative, migratory and invasive abilities via asymmetric division. To study the role of hypoxia‑inducible factor (HIF) 1α in the formation of PGCCs, colon cancer cell lines Hct116 and LoVo were used as experimental subjects. Western blotting, nuclear and cytoplasmic protein extraction and immunocytochemical experiments were used to compare the changes in the expression and subcellular localization of HIF1α, microphthalmia‑associated transcription factor (MITF), protein inhibitor of activated STAT protein 4 (PIAS4) and von Hippel‑Lindau disease tumor suppressor (VHL) after treatment with CoCl2. The SUMOylation of HIFα was verified by co‑immunoprecipitation assay. After inhibiting HIF1α SUMOylation, the changes in proliferation, migration and invasion abilities of Hct116 and LoVo were compared by plate colony formation, wound healing and Transwell migration and invasion. In addition, lysine sites that led to SUMOylation of HIF1α were identified through site mutation experiments. The results showed that CoCl2 can induce the formation of PGCCs with the expression level of HIF1α higher in treated cells than in control cells. HIF1α was primarily located in the cytoplasm of control cell. Following CoCl2 treatment, the subcellular localization of HIF1α was primarily in the nuclei of PGCCs with daughter cells (PDCs). After treatment with SUMOylation inhibitors, the nuclear HIF1α expression in PDCs decreased. Furthermore, their proliferation, migration and invasion abilities also decreased. After inhibiting the expression of MITF, the expression of HIF1α decreased. MITF can regulate HIF1α SUMOylation. Expression and subcellular localization of VHL and HIF1α did not change following PIAS4 knockdown. SUMOylation of HIF1α occurs at the amino acid sites K391 and K477 in PDCs. After mutation of the two sites, nuclear expression of HIF1α in PDCs was reduced, along with a significant reduction in the proliferation, migration and invasion abilities. In conclusion, the post‑translation modification regulated the subcellular location of HIF1α and the nuclear expression of HIF1α promoted the proliferation, migration and invasion abilities of PDCs. MITF could regulate the transcription and protein levels of HIF1α and participate in the regulation of HIF1α SUMOylation.

Benzimidazole-oxindole hybrids as multi-kinase inhibitors targeting melanoma

In the current study, a series of benzimidazole-oxindole conjugates 8a-t were designed and synthesized as type II multi-kinase inhibitors. They exhibited moderate to potent inhibitory activity against BRAFWT up to 99.61 % at 10 µM. Notably, compounds 8e, 8k, 8n and 8s demonstrated the most promising activity, with 99.44 to 99.61 % inhibition. Further evaluation revealed that 8e, 8k, 8n and 8s exhibit moderate to potent inhibitory effects on the kinases BRAFV600E, VEGFR-2, and FGFR-1. Additionally, compounds 8a-t were screened for their cytotoxicity by the NCI, and several compounds showed significant growth inhibition in diverse cancer cell lines. Compound 8e stood out with a GI50 range of 1.23 - 3.38 µM on melanoma cell lines. Encouraged by its efficacy, it was further investigated for its antitumor activity and mechanism of action, using sorafenib as a reference standard. The hybrid compound 8e exhibited potent cellular-level suppression of BRAFWT, VEGFR-2, and FGFR-1 in A375 cell line, surpassing the effects of sorafenib. In vivo studies demonstrate that 8e significantly inhibits the growth of B16F10 tumors in mice, leading to increased survival rates and histopathological tumor regression. Furthermore, 8e reduces angiogenesis markers, mRNA expression levels of VEGFR-2 and FGFR-1, and production of growth factors. It also downregulated Notch1 protein expression and decreased TGF-β1 production. Molecular docking simulations suggest that 8e binds as a promising type II kinase inhibitor in the target kinases interacting with the key regions in their kinase domain.

CircAGFG1 absence decreases PKM2 expression to enhance oxaliplatin sensitivity in colorectal cancer in a miR-7-5p-dependent manner

Circular RNA (circRNA) ArfGAP with FG repeats 1 (circAGFG1) contributes to colorectal cancer (CRC) development. However, whether circAGFG1 regulates the resistance of CRC to oxaliplatin (L-OHP) remains unknown. CircAGFG1, microRNA-7-5p (miR-7-5p) and pyruvate kinase M2 (PKM2) RNA expression were quantified by quantitative real-time polymerase chain reaction. Protein expression was detected by western blot assay and immunohistochemistry assay. Glycolysis was analyzed through glucose uptake, lactate production and adenosine triphosphate (ATP) concentration assays. 50% inhibitory concentration of L-OHP was determined by cell counting kit-8 assay. Cell proliferation and apoptotic rate were analyzed by cell colony formation and flow cytometry analysis, respectively. Dual-luciferase reporter assay was used to identify the relationship among circAGFG1, miR-7- 5p and PKM2. The effect of circAGFG1 on L-OHP sensitivity in vivo was further evaluated by a xenograft model assay. CircAGFG1 and PKM2 expression were significantly increased, while miR-7-5p was decreased in L-OHP-resistant CRC tissues and cells. High circAGFG1 expression predicted a poor prognosis of CRC. CircAGFG1 knockdown or PKM2 depletion decreased glycolysis and cell proliferation and increased L-OHP sensitivity and cell apoptosis. PKM2 introduction rescued circAGFG1 silencing-induced effects in CRC cells. In terms of mechanism, circAGFG1 bound to miR-7-5p, which was identified to target PKM2. Also, circAGFG1 regulated PKM2 expression by interacting with miR-7-5p. Further, circAGFG1 knockdown improved the sensitivity of tumors to L-OHP in vivo. CircAGFG1 depletion inhibited L-OHP resistance by regulating the miR-7-5p/PKM2 pathway.

Varying the RGD concentration on a hyaluronic acid hydrogel influences dormancy versus proliferation in brain metastatic breast cancer cells

A majority of breast cancer deaths occur due to metastasis of cancer cells to distant organs. In particular, brain metastasis is very aggressive with an extremely low survival rate. Breast cancer cells that metastasize to the brain can enter a state of dormancy, which allows them to evade death. The brain microenvironment provides biophysical, biochemical, and cellular cues, and plays an important role in determining the fate of dormant cancer cells. However, how these cues influence dormancy remains poorly understood. Herein, we employed hyaluronic acid (HA) hydrogels with a stiffness of ~0.4 kPa as an in vitro biomimetic platform to investigate the impact of biochemical cues, specifically alterations in RGD concentration, on dormancy versus proliferation in MDA-MB-231Br brain metastatic breast cancer cells. We applied varying concentrations of RGD peptide (0, 1, 2, or 4 mg/mL) to HA hydrogel surfaces and confirmed varying degrees of surface functionalization using a fluorescently labeled RGD peptide. Post functionalization, ~10,000 MDA-MB-231Br cells were seeded on top of the hydrogels and cultured for 5 days. We found that an increase in RGD concentration led to changes in cell morphology, with cells transitioning from a rounded to spindle-like morphology as well as an increase in cell spreading area. Also, an increase in RGD concentration resulted in an increase in cell proliferation. Cellular dormancy was assessed using the ratio of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK) to phosphorylated p38 (p-p38) positivity, which was significantly lower in hydrogels without RGD and in hydrogels with lowest RGD concentration compared to hydrogels functionalized with higher RGD concentration. We also demonstrated that the HA hydrogel-induced cellular dormancy was reversible. Finally, we demonstrated the involvement of β1 integrin in mediating cell phenotype in our hydrogel platform. Overall, our results provide insight into the role of biochemical cues in regulating dormancy versus proliferation in brain metastatic breast cancer cells.

Optimizing cryopreservation of nasal polyp tissue for cellular functional studies and single-cell RNA sequencing

KEY POINTS

Mast cell numbers were reduced in samples cryopreserved as whole tissue chunks. Thawed epithelial cells had reduced proliferation rates when preserved as dissociated cell suspensions. The right cryopreservation method to choose may depend on the goals and cell-type focus of the project.

Low UV radiation influenced DNA methylation, gene regulation, cell proliferation, viability, and biochemical differentiation in the cell suspension cultures of Cannabis indica

The effect of low artificial Ultraviolet (UV) on the DNA methylation remains controversial. This study addresses how differential photoperiods of UV radiation affect the biochemical and molecular behaviors of Cannabis indica cell suspension cultures. The cell suspensions were illuminated with the compact fluorescent lamps (CFL), emitting a combination of 10% UVB, 30% UVA, and the rest visible wavelengths for 0, 4, 8, and 16 h. The applied photoperiods influenced cell morphological characteristics. The 4 h photoperiod was the most effective treatment for improving biomass, growth index and cell viability percentage while these indices remained non-significant in the 16 h treatment. The methylation-sensitive amplified polymorphism (MASP) assay revealed that the UV radiation was epigenetically accompanied by DNA hypermethylation. The light-treated cells significantly displayed higher relative expression of the cannabidiolic‌ acid synthase (CBDAS) and delta9-tetrahydrocannabinolic acid synthase (THCAS) genes about 4-fold. The expression of the olivetolic acid cyclase (OAC) and olivetol synthase (OLS) genes exhibited an upward trend in response to the UV radiation. The light treatments also enhanced the proline content and protein concentration. The 4 h illumination was significantly capable of improving the cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) concentrations, in contrast with 16 h. By increasing the illumination exposure time, the activity of the phenylalanine ammonia-lyase (PAL) enzyme linearly upregulated. The highest amounts of the phenylpropanoid derivatives were observed in the cells cultured under the radiation for 4 h. Taken collective, artificial UV radiation can induce DNA methylation modifications and impact biochemical and molecular differentiation in the cell suspensions in a photoperiod-dependent manner.

Brusatol attenuated proliferation and invasion induced by KRAS in differentiated thyroid cancer through inhibiting Nrf2

BACKGROUND

Poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC) can be developed from differentiated thyroid cancer, and this dedifferentiated transformation leads to poor prognosis and high mortality. The role of Nrf2 in the dedifferentiation of differentiated thyroid cancer (DTC) induced by KRAS remains unclear.

METHODS AND MATERIALS

In this study, two DTC cell lines, BCPAP and WRO, were used to evaluate the function of Nrf2 in the dedifferentiation caused by wild-type KRAS (KRAS-WT) and G12V point mutation KRAS (KRAS-G12V).

RESULTS

The overexpression of KRAS-WT and KRAS-G12V increased the proliferative and invasive ability of BCPAP and WRO cells. Aggressive morphology was observed in KRAS-WT and KRAS-G12V overexpressed WRO cells. These results suggested that overexpression of KRAS-WT or KRAS-G12V may induce dedifferentiation in DTC cells. The expression of Nrf2 was increased by KRAS-WT and KRAS-G12V in DTC cells. In addition, compared with normal thyroid tissues, the expression of Nrf2 protein was considerably higher in thyroid cancer tissues on immunohistochemistry (IHC) staining, and the increased expression of Nrf2 indicated a poor prognosis of thyroid cancer. These results indicated that Nrf2 is the KRAS downstream molecule in thyroid cancer. Functional studies showed that the Nrf2 inhibitor Brusatol counteracted the proliferative and invasive abilities induced by KRAS-WT and KRAS-G12V in BCPAP and WRO cells. In addition, the xenograft assay further confirmed that Brusatol inhibits tumor growth induced by KRAS-WT and KRAS-G12V.

CONCLUSION

Collectively, this study suggests that Nrf2 could be a promising therapeutic target in KRAS-mediated dedifferentiation of thyroid cancer.

CircNRCAM up-regulates NRCAM to promote papillary thyroid carcinoma progression

PURPOSE

Papillary Thyroid Carcinoma (PTC) is the most prevalent subtype of Thyroid Carcinoma (THCA), a type of malignancy in the endocrine system. According to prior studies, Neural Cell Adhesion Molecule (NRCAM) has been found to be up-regulated in PTC and stimulates the proliferation and migration of PTC cells. However, the specific mechanism of NRCAM in PTC cells is not yet fully understood. Consequently, this study aimed to investigate the underlying mechanism of NRCAM in PTC cells, the findings of which could provide new insights for the development of potential treatment targets for PTC.

METHODS AND RESULTS

Bioinformatics tools were utilized and a series of experiments were conducted, including Western blot, colony formation, and dual-luciferase reporter assays. The data collected indicated that NRCAM was overexpressed in THCA tissues and PTC cells. Circular RNA NRCAM (circNRCAM) was found to be highly expressed in PTC cells and to positively regulate NRCAM expression. Through loss-of-function assays, both circNRCAM and NRCAM were shown to promote the proliferation, invasion, and migration of PTC cells. Mechanistically, this study confirmed that precursor microRNA-506 (pre-miR-506) could bind with m6A demethylase AlkB Homolog 5 (ALKBH5), leading to its m6A demethylation. It was also discovered that circNRCAM could competitively bind to ALKBH5, which restrained miR-506-3p expression and promoted NRCAM expression.

CONCLUSION

In summary, circNRCAM could up-regulate NRCAM by down-regulating miR-506-3p, thereby enhancing the biological behaviors of PTC cells.

Compound 225# inhibits the proliferation of human colorectal cancer cells by promoting cell cycle arrest and apoptosis induction

Colorectal cancer (CRC) ranks as the second leading cause of cancer‑related death worldwide due to its aggressive nature. After surgical resection, >50% of patients with CRC require adjuvant therapy. As a result, eradicating cancer cells with medications is a promising method to treat patients with CRC. In the present study, a novel compound was synthesized, which was termed compound 225#. The inhibitory activity of compound 225# against CRC was determined by MTT assay, EdU fluorescence labeling and colony formation assay; the effects of compound 225# on the cell cycle progression and apoptosis of CRC cells were detected by flow cytometry and western blotting; and the changes in autophagic flux after the administration of compound 225# were detected using the double fluorescence fusion protein mCherry‑GFP‑LC3B and western blotting. The results demonstrated that compound 225# exhibited antiproliferative properties, inhibiting the proliferation and expansion of CRC cell lines in a time‑ and dose‑dependent manner. Furthermore, compound 225# triggered G2/M cell cycle arrest by influencing the expression of cell cycle regulators, such as CDK1, cyclin A1 and cyclin B1, which is also closely related to the activation of DNA damage pathways. The cleavage of PARP and increased protein expression levels of PUMA suggested that apoptosis was triggered after treatment with compound 225#. Moreover, the increase in LC3‑II expression and stimulation of autophagic flux indicated the activation of an autophagy pathway. Notably, compound 225# induced autophagy, which was associated with endoplasmic reticulum (ER) stress. In accordance with the in vitro findings, the in vivo results demonstrated that compound 225# effectively inhibited the growth of HCT116 tumors in mice without causing any changes in their body weight. Collectively, the present results demonstrated that compound 225# not only inhibited proliferation and promoted G2/M‑phase cell cycle arrest and apoptosis, but also initiated cytoprotective autophagy in CRC cells by activating ER stress pathways. Taken together, these findings provide an experimental basis for the evaluation of compound 225# as a novel potential medication for CRC treatment.

Natural compound Byakangelicin suppresses breast tumor growth and motility by regulating SHP-1/JAK2/STAT3 signal pathway

Byakangelicin mostly obtained from the root of Angelica dahurica and has protective effect on liver injury and fibrosis. In addition, Byakangelicin, as a traditional medicine, is also used to treat colds, headache and toothache. Recent studies have shown that Byakangelicin exhibits anti-tumor function; however, the role of Byakangelicin in breast tumor progression and related mechanism has not yet been elucidated. Our study aims to investigate the role of Byakangelicin in breast tumor progression and the underlying mechanism. To measure the effect of Byakangelicin on JAK2/STAT3 signaling, a dual luciferase reporter assay and a Western blot assay were performed. CCK8, colony formation, apoptosis and cell invasion assays were used to examine the inhibitory potential of Byakangelicin on breast cancer cells. Additionally, SHP-1 was silenced by specific siRNA duplex and the function of SHP-1 on Byakangelicin-mediated inhibition of JAK2/STAT3 signaling was evaluated. Byakangelicin treatment significantly inhibited STAT3 transcriptional activity. In addition, Byakangelicin treatment blocked JAK2/STAT3 signaling in a dose-dependent manner. Byakangelicin-treated tumor cells showed a dramatically reduced proliferation, colony formation and invasion ability. Moreover, Byakangelicin remarkedly induced breast cancer cell apoptosis. Furthermore, Byakangelicin regulated the expression of SHP1.In conclusion, our current study indicated that Byakangelicin, a natural compound, inhibits SHP-1/JAK2/STAT3 signaling and thus blocks tumor growth and motility.

Lnc-PLCB1 is stabilized by METTL14 induced m6A modification and inhibits Helicobacter pylori mediated gastric cancer by destabilizing DDX21

Helicobacter pylori (H. pylori) infection is considered to be an important factor in gastric cancer (GC). Long noncoding RNA (lncRNA) and m6A modification are involved in the occurrence and development of GC, but the role of lncRNA m6A modification in the development of GC mediated by H. pylori is still unclear. Here, we found that H. pylori infection downregulated the expression of lnc-PLCB1 through METTL14-mediated m6A modification and IRF2-mediated transcriptional regulation. Overexpression of lnc-PLCB1 inhibited the proliferation and migration of GC cells, while downregulation of lnc-PLCB1 promoted the proliferation and migration ability of GC cells. In addition, clinical analysis showed that lnc-PLCB1 is lower in GC tissues than in normal tissues. Further study found that lnc-PLCB1 reduced the protein stability of its binding protein DEAD-box helicase 21 (DDX21) and then downregulated the expression of CCND1 and Slug, thereby playing tumour suppressing role in the occurrence and development of GC. In conclusion, the METTL14/lnc-PLCB1/DDX21 axis plays an important role in H. pylori-mediated GC, and lnc-PLCB1 can be used as a new target for GC treatment.

CircUBE3A(2,3,4,5) promotes adenylate-uridylate-rich binding factor 1 nuclear translocation to suppress prostate cancer metastasis

Metastatic progression is the primary cause of mortality in prostate cancer (PCa) patients. Although circular RNAs (circRNAs) have been implicated in cancer progression and metastasis, our current understanding of their role in PCa metastasis remains limited. In this study, we identified that circUBE3A(2,3,4,5), which originated from exons 2, 3, 4 and 5 of the human ubiquitin-protein ligase E3A (UBE3A) gene, was specifically downregulated in PCa tissues and correlated with the Gleason score, bone metastasis, and D'Amico risk classification. Through the in vitro and in vivo experiments, we demonstrated that overexpression of circUBE3A(2,3,4,5) inhibited PCa cell migration, invasion, metastasis, and proliferation. Mechanistically, circUBE3A(2,3,4,5) was found to bind to adenylate-uridylate-rich binding factor 1 (AUF1), promoting the translocation of AUF1 into the nucleus. This led to decreased AUF1 in the cytoplasm, resulting in methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) mRNA instability and a subsequent reduction at the protein level. The downregulation of MTHFD2 further inhibited vimentin expression, thereby suppressing PCa cell epithelial-mesenchymal transition. Additionally, two pairs of the short-inverted repeats (TSIRs) in flanking introns were identified to synergistically facilitate the generation of circUBE3A(2,3,4,5) and other circRNAs. In summary, TSIRs-induced circUBE3A(2,3,4,5) acts as a suppressor of PCa metastasis by enhancing AUF1 nuclear translocation, reducing MTHFD2, and subsequently inhibiting vimentin expression. This study characterizes circUBE3A(2,3,4,5) as a functional circRNA and proposes it as a highly promising target for preventing PCa metastasis.

CD63+ cancer-associated fibroblasts confer CDK4/6 inhibitor resistance to breast cancer cells by exosomal miR-20

Cyclin-dependent kinase 4 (CDK4) and CDK6 inhibitors (CDK4/6i) have rapidly received Food and Drug Administration (FDA) approval as a new type of therapy for patients with advanced hormone receptor-positive breast cancer. However, with the widespread application of CDK4/6i, drug resistance has become a new challenge for clinical practice and has greatly limited the treatment effect. Here, the whole microenvironment landscape of ER+ breast cancer tumors was revealed through single-cell RNA sequencing, and a specific subset of cancer-associated fibroblasts (CD63+ CAFs) was identified as highly enriched in CDK4/6i resistant tumor tissues. Then, we found that CD63+ CAFs can distinctly promote resistance to CDK4/6i in breast cancer cells and tumor xenografts. In addition, it was discovered that miR-20 is markedly enriched in the CD63+ CAFs-derived exosomes, which are used to communicate with ER+ breast cancer cells, leading to CDK4/6i resistance. Furthermore, exosomal miR-20 could directly target the RB1 mRNA 3'UTR and negatively regulate RB1 expression to decrease CDK4/6i sensitivity in breast cancer cells. Most importantly, we designed and synthesized cRGD-miR-20 sponge nanoparticles and found that they can enhance the therapeutic effect of CDK4/6i in breast cancer. In summary, our findings reveal that CD63+ CAFs can promote CDK4/6i resistance via exosomal miR-20, which induces the downregulation of RB1 in breast cancer cells, and suggest that CD63+ CAFs may be a novel therapeutic target to enhance CDK4/6i sensitivity.

LINC02454-CCT complex interaction is essential for telomerase activity and cell proliferation in head and neck squamous cell carcinoma

Telomerase activity is upregulated in head and neck squamous cell carcinoma (HNSCC), yet its regulatory mechanisms remain unclear. Here, we identified a cancer-specific lncRNA (LINC02454) associated with poor prognosis by using LncRNA chip of our HNSCC cohorts and external datasets. Through employing negative-stain transmission electron microscopy (NS-TEM), we discovered an interaction between LINC02454 and CCT complex which would augment telomerase activity for maintaining telomere homeostasis. Supporting this, in the telomerase repeat amplification protocol (TRAP) assay and quantitative fluorescence in situ hybridization (Q-FISH) analysis, LINC02454 depletion significantly reduced telomerase activity and shortened telomere length. Consistently, pathways related to telomerase, mitosis, and apoptosis were significantly impacted upon LINC02454 knockdown in RNAseq analysis. Functionally, LINC02454-deficient cells exhibited a more significant senescence phenotype in β-galactosidase staining, cell cycle, and apoptosis assays. We further confirmed the role of LINC02454 in HNSCC proliferation through a combination of in vitro and in vivo experiments. The therapeutic potential of targeting LINC02454 was verified by adenovirus-shRNA approach in HNSCC patient-derived xenograft (PDX) models. In summary, our findings provided valuable insights into the molecular mechanisms of HNSCC tumorigenesis and potential targets for future treatment modalities.

TIF1γ and SMAD4 regulation in colorectal cancer: impact on cell proliferation and liver metastasis

We investigated the effects of transcriptional intermediary factor 1γ (TIF1γ) and SMAD4 on the proliferation and liver metastasis of colorectal cancer (CRC) cells through knockdown of TIF1γ and/or SMAD4 and knockdown of TIF1γ and/or restoration of SMAD4 expression. Furthermore, we examined TIF1γ and SMAD4 expression in human primary CRC and corresponding liver metastatic CRC specimens. TIF1γ promoted but SMAD4 inhibited the proliferation of CRC cells by competitively binding to activated SMAD2/SMAD3 complexes and then reversely regulating c-Myc, p21, p27, and cyclinA2 levels. Surprisingly, both TIF1γ and SMAD4 reduced the liver metastasis of all studied CRC cell lines via inhibition of MEK/ERK pathway-mediated COX-2, Nm23, uPA, and MMP9 expression. In patients with advanced CRC, reduced TIF1γ or SMAD4 expression was correlated with increased invasion and liver metastasis and was a significant, independent risk factor for recurrence and survival after radical resection. Patients with advanced CRC with reduced TIF1γ or SAMD4 expression had higher recurrence rates and shorter overall survival. TIF1γ and SMAD4 competitively exert contrasting effects on cell proliferation but act complementarily to suppress the liver metastasis of CRC via MEK/ERK pathway inhibition. Thus, reduced TIF1γ or SMAD4 expression in advanced CRC predicts earlier liver metastasis and poor prognosis.

Mefenamic acid exhibits antitumor activity against osteosarcoma by impeding cell growth and prompting apoptosis in human osteosarcoma cells and xenograft mice model

The study investigates the anticancer activity of mefenamic acid against osteosarcoma, shedding light on its underlying mechanisms and therapeutic potential. Mefenamic acid exhibited robust inhibitory effects on the proliferation of MG-63, HOS, and H2OS osteosarcoma cells in a dose-dependent manner. Moreover, mefenamic acid induced cellular toxicity in MG63 cells, as evidenced by LDH leakage, reflecting its cytotoxic impact. Furthermore, mefenamic acid effectively suppressed the migration and invasion of MG-63 cells. Mechanistically, mefenamic acid induced apoptosis in MG-63 cells through mitochondrial depolarization, activation of caspase-dependent pathways, and modulation of the Bcl-2/Bax axis. Additionally, mefenamic acid promoted autophagy and inhibited the PI3K/Akt/mTOR pathway, further contributing to its antitumor effects. The molecular docking studies provide compelling evidence that mefenamic acid interacts specifically and strongly with key proteins in the PI3K/AKT/mTOR pathway, suggesting a novel mechanism by which mefenamic acid could exert anti-osteosarcoma effects. In vivo studies using a xenograft mouse model demonstrated significant inhibition of MG-63 tumor growth without adverse effects, supporting the translational potential of mefenamic acid as a safe and effective therapeutic agent against osteosarcoma. Immunohistochemistry staining corroborated the in vivo findings, highlighting mefenamic acid's ability to suppress tumor proliferation and inhibit the PI3K/AKT/mTOR pathway within the tumor microenvironment. Collectively, these results underscore the promising therapeutic implications of mefenamic acid in combating osteosarcoma, warranting further investigation for clinical translation and development.

High core 1β1,3-galactosyltransferase 1 expression is associated with poor prognosis and promotes cellular radioresistance in lung adenocarcinoma

PURPOSE

Core 1β1,3-galactosyltransferase 1 (C1GALT1) exhibits elevated expression in multiple cancers. The present study aimed to elucidate the clinical significance of C1GALT1 aberrant expression and its impact on radiosensitivity in lung adenocarcinoma (LUAD).

METHODS

The C1GALT1 expression and its clinical relevance were investigated through public databases and LUAD tissue microarray analyses. A549 and H1299 cells with either C1GALT1 knockdown or overexpression were further assessed through colony formation, gamma-H2A histone family member X immunofluorescence, 5-ethynyl-2'-deoxyuridine incorporation, and flow cytometry assays. Bioinformatics analysis was used to explore single cell sequencing data, revealing the influence of C1GALT1 on cancer-associated cellular states. Vimentin, N-cadherin, and E-cadherin protein levels were measured through western blotting.

RESULTS

The expression of C1GALT1 was significantly higher in LUAD tissues than in adjacent non-tumor tissues both at mRNA and protein level. High expression of C1GALT1 was correlated with lymph node metastasis, advanced T stage, and poor survival, and was an independent risk factor for overall survival. Radiation notably upregulated C1GALT1 expression in A549 and H1299 cells, while radiosensitivity was increased following C1GALT1 knockdown and decreased following overexpression. Experiment results showed that overexpression of C1GALT1 conferred radioresistance, promoting DNA repair, cell proliferation, and G2/M phase arrest, while inhibiting apoptosis and decreasing E-cadherin expression, alongside upregulating vimentin and N-cadherin in A549 and H1299 cells. Conversely, C1GALT1 knockdown had opposing effects.

CONCLUSION

Elevated C1GALT1 expression in LUAD is associated with an unfavorable prognosis and contributes to increased radioresistance potentially by affecting DNA repair, cell proliferation, cell cycle regulation, and epithelial-mesenchymal transition (EMT).

Galectin-9, a pro-survival factor inducing immunosuppression, leukemic cell transformation and expansion

Leukemia is a malignancy of the bone marrow and blood originating from self-renewing cancerous immature blast cells or transformed leukocytes. Despite improvements in treatments, leukemia remains still a serious disease with poor prognosis because of disease heterogeneity, drug resistance and relapse. There is emerging evidence that differentially expression of co-signaling molecules play a critical role in tumor immune evasion. Galectin-9 (Gal-9) is one of the key proteins that leukemic cells express, secrete, and use to proliferate, self-renew, and survive. It also suppresses host immune responses controlled by T and NK cells, enabling leukemic cells to evade immune surveillance. The present review provides the molecular mechanisms of Gal-9-induced immune evasion in leukemia. Understanding the complex immune evasion machinery driven by Gal-9 expressing leukemic cells will enable the identification of novel therapeutic strategies for efficient immunotherapy in leukemic patients. Combined treatment approaches targeting T-cell immunoglobulin and mucin domain-3 (Tim-3)/Gal-9 and other immune checkpoint pathways can be considered, which may enhance the efficacy of host effector cells to attack leukemic cells.

CircCOL1A1 promotes proliferation, migration, and invasion of colorectal cancer (CRC) cells and glutamine metabolism through GLS1 up-regulation by sponging miR-214-3p

BACKGROUND

Circular ribose nucleic acids (circRNAs), an abundant type of noncoding RNAs, are widely expressed in eukaryotic cells and exert a significant impact on the initiation and progression of various disorders, including different types of cancer. However, the specific role of various circRNAs in colorectal cancer (CRC) pathology is still not fully understood.

METHODS

The initial step involved the use of quantitative reverse transcription polymerase chain reaction (RT-qPCR) to assess the expression levels of circRNAs and messenger RNA (mRNA) in CRC cell lines and tissues. Subsequently, functional analyses of circCOL1A1 knockdown were conducted in vitro and in vivo through cell counting kit (CCK)-8, colony formation and transwell assays, as well as xenograft mouse model of tumor formation. Molecular expression and interactions were investigated using luciferase reporter assays, Western blot analysis, RNA immunoprecipitation (RIP), and immunohistochemical staining.

RESULTS

The RT-qPCR results revealed elevated levels of circCOL1A1 expressions in CRC tissues and cell lines as compared to the normal counterparts. In addition, circCOL1A1 expression level was found to be correlated with TNM stage, lymph node metastases, distant metastases, and invasion. Knockdown of circCOL1A1 resulted in impaired invasion, migration, and proliferation of CRC cells, and suppressed tumor generation in the animal model. We further demonstrated that circCOL1A1 could act as a sponge for miR-214-3p, suppressing miR-214-3p activity and leading to the upregulation of GLS1 protein to promote glutamine metabolism.

CONCLUSION

These findings suggest that circCOL1A1 functions as an oncogenic molecule to promote CRC progression via miR-214-3p/GLS1 axis, hinting on the potential of circCOL1A1 as a therapeutic target for CRC.

Interleukin 33 supports squamous cell carcinoma growth via a dual effect on tumour proliferation, migration and invasion, and T cell activation

Interleukin (IL)-33 is an important cytokine in the tumour microenvironment; it is known to promote the growth and metastasis of solid cancers, such as gastric, colorectal, ovarian and breast cancer. Our group demonstrated that the IL-33/ST2 pathway enhances the development of squamous cell carcinoma (SCC). Conversely, other researchers have reported that IL-33 inhibits tumour progression. In addition, the crosstalk between IL-33, cancer cells and immune cells in SCC remains unknown. The aim of this study was to investigate the effect of IL-33 on the biology of head and neck SCC lines and to evaluate the impact of IL-33 neutralisation on the T cell response in a preclinical model of SCC. First, we identified epithelial and peritumoural cells as a major local source of IL-33 in human SCC samples. Next, in vitro experiments demonstrated that the addition of IL-33 significantly increased the proliferative index, motility and invasiveness of SCC-25 cells, and downregulated MYC gene expression in SCC cell lines. Finally, IL-33 blockade significantly delayed SCC growth and led to a marked decrease in the severity of skin lesions. Importantly, anti-IL-33 monoclonal antibody therapy increase the percentage of CD4+IFNγ+ T cells and decreased CD4+ and CD8+ T cells secreting IL-4 in tumour-draining lymph nodes. Together, these data suggest that the IL-33/ST2 pathway may be involved in the crosstalk between the tumour and immune cells by modulating the phenotype of head and neck SCC and T cell activity. IL-33 neutralisation may offer a novel therapeutic strategy for SCC.