Cell Lines SiHa Research Articles

Abstract P002: FLASH radiotherapy enhances immune activation and spares lymphocytes tumor draining lymph nodes

Abstract Introduction: Conventional radiotherapy (CRT) causes antagonizing anti-tumor immune responses by depleting circulating immune cells. Given the normal tissue sparing associated with FLASH radiotherapy (FLASH-RT), we hypothesized that FLASH-RT rescues naïve lymphocytes while increasing the immunogenicity of cancer cells. Methods: Murine cancer cell lines TC-1 and MEER as well as the human cancer cell lines Caski, SiHA and SCC153 were irradiated using a Mobetron (IntraOp, Sunnyvale, CA) under FLASH-RT at 270.0 Gy/sec (3.00 Gy per pulse ) or CRT 0.209 Gy/sec dose rates. MEER tumors in immunocompetent C56BL/6 mice were irradiated with 27 Gy in 3 fractions. We assessed expression of immunogenic proteins calreticulin (CALR) and HMGB1 using immunofluorescence and cGAS, STING, IFNalpha and IFNbeta using qRT-PCR. Lymph node immune cells were assessed for CD8, CD4, CD62L and CD44 to assess lymphocyte subpopulations and activation. Tumors were assessed for CD3, CD8, PD1, PD-L1, F4/80 to assess immune cell infiltration 5 days after radiotherapy. Two-way ANOVA and Student’s t-test were used for paired-wise comparisons. Results: Both human and murine positive cell lines showed similar upregulation of CALR and HMGB1 and cGAS-STING family members after FLASH-RT or CRT in vitro. One cell line, TC-1, demonstrated increased expression Hmgb1 (4.2 vs 1.0-fold; p<0.001 ), cGAS (1.9 vs 1.0-fold; p<0.001 ) and STING (2.2 vs 0.9-fold; p<0.001 ) 24h after irradiation to 9 Gy or 12 Gy using FLASH-RT. In mice bearing MEER tumors, draining lymph nodes contained greater CD8+ T cells (P<0.001) and CD4+ T cells (p>0.01) in tumors irradiated with FLASH-RT compared to tumors irradiated with CRT. FLASH-RT was associated with increased CD44+CD62Llo CD8+ (P<0.01) and CD4+ (P<0.05) lymphocytes indicating increased activated T cells in FLASH-RT treated tumors compare to CRT treated tumors. In irradiated tumors, FLASH-RT was associated with increased CD8+ tumor infiltrating lymphocytes, increased PD-1 expression on CD8+ tumor infiltrating lymphocytes and increased PD-L1 on macrophages (P<0.001). Conclusion: Compared to CRT, FLASH-RT spared activated T cells in tumor draining lymph nodes and in tumors but increased checkpoint inhibitor expression in tumors. These results suggest that FLASH-RT may enhance anti-tumor immune responses by maintaining the immunogenic effects of radiotherapy that can be augmented with immune checkpoint blockade. Citation Format: Francisco Saenz, Brett Velasquez, Abagail Delahoussaye, Luke Connell, Nefetiti Mims, Denae Neill, Emil Schüler, Michael Spiotto. FLASH radiotherapy enhances immune activation and spares lymphocytes tumor draining lymph nodes. [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Translating Targeted Therapies in Combination with Radiotherapy; 2025 Jan 26-29; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2025;31(2_Suppl):Abstract nr P002

Effects of Arborvitae (Thuja plicata) Essential Oil on Cervical Cancer Cells: Insights into Molecular Mechanisms.

This study aimed to assess the effects of AEO in an in vitro model of cell lines derived from cervical cancer-namely, HeLa and SiHa-by screening for AEO's cytotoxic properties and examining its influence on the modulation of gene expression. Cervical cancer stands as a prevalent global health concern, affecting millions of women worldwide. The current treatment modalities encompass surgery, radiation, and chemotherapy, but significant limitations and adverse effects constrain their effectiveness. Therefore, exploring novel treatments that offer enhanced efficacy and reduced side effects is imperative. Arborvitae essential oil, extracted from Thuja Plicata, has garnered attention for its antimicrobial, anti-inflammatory, immunomodulatory, and tissue-remodeling properties; however, its potential in treating cervical cancer remains uncharted. The objective of this study was to delve into the molecular mechanisms induced by arborvitae essential oil in order to learn about its anticancer effects on cervical cancer cell lines. The methods used in this study were assessments of cell viability using WST-1 and annexin V- propidium iodide, mRNA sequencing, and subsequent bioinformatics analysis. The findings unveiled a dose-dependent cytotoxic effect of arborvitae essential oil on both HeLa and SiHa cell lines. Minor effects were observed only at very low doses in the HaCaT non-tumorigenic human keratinocyte cells. RNA-Seq bioinformatics analysis revealed the regulatory impact of arborvitae essential oil on genes enriched in the following pathways: proteasome, adherens junctions, nucleocytoplasmic transport, cell cycle, proteoglycans in cancer, protein processing in the endoplasmic reticulum, ribosome, spliceosome, mitophagy, cellular senescence, and viral carcinogenesis, among others, in both cell lines. It is worth noting that the ribosome and spliceosome KEGG pathways are the most significantly enriched pathways in HeLa and SiHa cells. Arborvitae essential oil shows potential as a cytotoxic and antiproliferative agent against cervical cancer cells, exerting its cytotoxic properties by regulating many KEGG pathways.

Therapeutic efficacy of CRISPR RNA nanoparticles on cervical cancer disease using ultrasound elastography imaging

This work aimed to evaluate the therapeutic efficacy of clustered regularly interspaced short palindromic repeats (CRISPR) ribonucleic acid (RNA) nanoparticles (NPs) in the therapy of cervical cancer (CC) using ultrasound elastography imaging. Using poly(β-amino esters) (PBAE), CRISPR RNA NPs encapsulating Human Papillomavirus 16 (HPV16) E7, namely Poly(β-amino ester) (PBAE)/CRISPR16E7-GFP and PBAE/shRNA-16E7, were prepared. The characterization of these NPs was conducted using transmission electron microscopy (TEM) and laser diffraction particle size analysis. The cytotoxicity of PBAE/CRISPR16E7-GFP and PBAE/shRNA-16E7 NPs on CC cell lines SiHa, HeLa, and CaSki was assessed using the cell counting kit-8 (CCK-8) assay. Sixty female Sprague Dawley (SD) rats were rolled into six groups randomlyas follows: the blank Ctrl group (Group A, no treatment), the model group (Group B, CC model), the pSpCas9-GFP plasmid group (Group C, CC model + pSpCas9-GFP), the PBAE/CRISPR-16E7 group (Group D, CC model + PBAE/CRISPR-16E7), the pSIREN-U6-shRNA-CMV-iRFP plasmid group (Group E, CC model + pSIREN-U6-shRNA-CMV-iRFP), and the PBAE/shRNA-16E7 group (Group F, CC model + PBAE/shRNA-16E7), each consisting of 10 rats. The impact of NPs on the expression levels (ELs) of HPV16E7 and RB1 proteins in tumor tissues was assessed using Western Blot (WB) analysis. Additionally, ultrasound elastography imaging was employed to analyze the strain ratio (SR) and shear wave velocity (SWV) in lesions of various rat groups. The results indicated that the PBAE/CRISPR16E7-GFP NPs exhibited a particle size of 125.64 ± 7.8 nm, a zeta potential of 19.17 ± 3.61 mV, and a polydispersity index (PDI) of 0.281 ± 0.03. These NPs demonstrated a regular spherical structure with a compact morphology. The PBAE/shRNA-16E7 NPs displayed a particle size of 112.93 ± 9.1 nm, a zeta potential of 13.54 ± 1.39 mV, and a PDI of 0.185 ± 0.03. They exhibited a uniform distribution of spherical shape with regularity in size. The plasmids within PBAE/CRISPR16E7-GFP and PBAE/shRNA-16E7 NPs exhibited distinct trends of burst and sustained release. The viability of SiHa, HeLa, and CaSki cells remained unaffected by PBAE/CRISPR16E7-GFP NPs. At various mass ratios, neglectable differences (P > 0.05) were observed in cell viability of SiHa, HeLa, and CaSki cells treated with PBAE/CRISPR16E7-GFP and PBAE/shRNA-16E7 NPs relative to Ctrl group. Relative to Group B, both Groups C and E exhibited a drastic decrease in tumor volume, tumor mass, and HPV16E7 protein ELs (P < 0.05), whereas Groups D and F showed a notably greater reduction in tumor volume, tumor mass, and HPV16E7 protein ELs (P < 0.01). The HPV16E7 protein ELs, SR, and SWV values greatly increased (P < 0.001) in tumors of Group B rats while the EL of RB1 protein notably decreased (P < 0.001) versus Group A. Groups C and E demonstrated elevated HPV16E7 ELs, SR, and SWV values (P < 0.05), with a marked decrease in RB1 protein EL (P < 0.001). Group F exhibited a notable reduction in HPV16E7 protein levels, SR, and SWV values (P < 0.001).The CRISPRRNA NPs composed of PBAE encapsulating HPV16 E7, namely PBAE/CRISPR16E7-GFP and PBAE/shRNA-16E7 plasmids, demonstrated a significant role in CC therapy. These NPs hold potential application value in the treatment of HPV-related CC, indicating their importance in addressing this particular disease.

Curcumin enhances ATG3-dependent autophagy and inhibits metastasis in cervical carcinoma

Cervical carcinoma poses a significant health threat, with traditional treatments proving inadequate in advanced stages. Curcumin, a bioactive compound derived from turmeric, exhibits notable anti-inflammatory, antioxidant, and antineoplastic properties, potentially modulating autophagy, and metastasis in cancer cells. This study examines curcumin’s impact on autophagy and metastasis in cervical carcinoma, focusing on its interaction with autophagy-related gene 3 (ATG3). SiHa and HeLa cervical carcinoma cell lines were treated with curcumin, ATG3 knockdown (shATG3), and their combination. Cell migration was evaluated via wound healing assays, while cell proliferation was evaluated with CCK-8 assays. LC3 expression was assessed using immunofluorescence and western blotting. Molecular docking simulations identified curcumin’s binding interactions with key proteins. Curcumin and shATG3 significantly inhibited both cell migration and proliferation, with a synergistic effect observed when combined. LC3 expression was enhanced, indicating increased autophagy. Docking studies revealed curcumin’s potential binding to MMP2, MMP9, TGF-β, ATG3, LC3, and p62, suggesting modulation of these pathways. The combination of curcumin and ATG3 knockdown significantly inhibited cervical carcinoma cell migration and proliferation, while also enhancing autophagy, supporting the potential of curcumin as a therapeutic agent for cervical carcinoma. Further clinical research is needed to validate these findings.Graphical abstract

3-Dimensional multicellular aggregates of human cervical cancer cell line SiHa – getting to the core of their morphologies

3-Dimensional (3D) cultures of cancer cell lines exhibit unique morphologies, a feature that can be utilized for understanding several aspects of solid tumors. This study aims to investigate the morphology and morphometrics of agarose hydrogel-induced 3D aggregates of SiHa cell line. Floating 3D aggregates of SiHa cells were obtained using liquid overlay technique on 1 % agarose hydrogel. The aggregates were monitored daily for its progressive growth and morphology, and documented. The morphometric analysis of the multicellular 3D spheroids were performed on cultures in the late exponential/log phase (the 93rd hour in culture). The morphology exhibited by the 3D aggregates at this stage was “grape-like”. Three morphometric parameters viz. average area, average number, and average roundness of aggregates, were determined and was found that the compactness of the aggregates was the maximum on Day 5 post-seeding. Additionally, the aggregates exhibited multi-acinar structures and extracellular matrix, characteristic of tumour progression. Establishing the morphological parameters of SiHa is an approach to better understand the characteristics of 3D aggregates. Such analysis has a direct bearing on translational benefits towards solid tumour research.

Diagnostic potential of miRNA-135A1 in human papillomavirus associated cervical lesions

Introduction. Human papillomavirus (HPV) infection with high-risk HPVs is an etiological factor in the development of cervical cancer, with HPV type 16 (HPV16) being the most common. The mechanisms leading to disruption of viral oncogene expression and initiation of epithelial cell transformation are poorly understood. Epigenetic regulatory factors, including cellular miRNAs, may play an important role in HPV-induced carcinogenesis, and aberrantly expressed miRNAs may be promising markers for the diagnosis of HPV-associated lesions.Aim. To search for miRNAs involved in the pathogenesis of HPV16-associated cervical cancer and to evaluate their diagnostic potential for the detection of cervical cancer and precancerous lesions.Materials and methods. MiRNA expression in clinical samples was assessed by both next generation sequencing and quantitative stem-loop polymerase chain reaction (sl-qPCR). Plasma miRNAs from patients with precancerous and cancerous lesions and healthy donors were analyzed using sl-qPCR. Loss of heterozygosity in cervical cancer samples was assessed by copy number ratio of MIR135A1 and ACTB genes. A total of 67 patients with cervical cancer, 21 with precancerous cervical lesions and 24 healthy donors were included in the study. The effect of DNA methylation on miRNA-135A1 expression was evaluated after treatment with a demethylating agent of the cervical HPV16-positive SiHa cell line. Changes in the expression of the HPV16 E6 oncogene were analyzed after transfection with synthetic analogues of the mature forms of miRNA-135А1 (miRNA-135a-3p and miRNA-135a-5p).Results. A significant decrease in the expression of miRNA-135A1 and miRNA-135A2 was detected in tumor tissue samples from HPV16-positive cervical cancer, which was confirmed by sl-qPCR in an independent panel of tumor samples. A decrease in miRNA-135A1 expression was shown to result from both loss of heterozygosity of the gene and aberrant DNA methylation. Transfection of mature forms of miRNA-135A1 into SiHa cells resulted in decreased expression of the E6 oncogene of HPV16. Blood plasma samples from patients with cervical cancer and precancerous lesions showed lower levels of miRNA-135a-3p than healthy donors, and ROC analysis indicated its high diagnostic potential.Conclusion. Levels of miRNA-135A1 are significantly reduced in cervical lesions, both in tumor tissue and plasma, and the ability of this miRNA to suppress the expression of the HPV16 E6 oncogene suggests its oncosuppressive properties. Thus, miRNA-135A1 can be used as a promising new marker for the diagnosis of HPV-associated lesions.

Emodin combined with 5-aminolevulinic acid photodynamic therapy inhibits condyloma acuminate angiogenesis by targeting SerRS.

Human papillomavirus (HPV) infection can cause condyloma acuminatum (CA), which is characterized by a high incidence and a propensity for recurrence after treatment. Angiogenesis plays an important role in the occurrence and development of CA. Seryl-tRNA synthetase (SerRS) is a newly identified, potent anti-angiogenic factor that directly binds to the vascular endothelial growth factor (VEGFA) promoter, thereby suppressing its transcription. Emodin is a natural anthraquinone derivative that can promote SerRS expression. This study aimed to investigate the effects of emodin on CA and explore combined treatment strategies. The HPV-infected cell line SiHa was treated with either DMSO, emodin, ALA-PDT or a combination of emodin and ALA-PDT. We observed the effects on cell proliferation, apoptosis and the SerRS-VEGFA pathway. Our findings demonstrated that emodin targets angiogenesis through the SerRS-VEGFA pathway, resulting in the inhibition of SiHa cell proliferation and promotion of apoptosis (p < 0.001). To verify the therapeutic effect of emodin combined with ALA-PDT on HPV-associated tumours invivo, we established an animal xenograft model by subcutaneously inoculating mice with SiHa cells (n = 4). The results showed that the combination of emodin and ALA-PDT significantly inhibited the expression of VEGFA to inhibit angiogenesis (p < 0.001), thus showing an inhibitory effect on tumour (p < 0.001). Furthermore, we determined that the mechanism underlying the decrease in VEGFA expression after emodin combined with ALA-PDT in CA may be attributed to the promotion of SerRS expression (p < 0.001). The combination of emodin and ALA-PDT holds promise as a novel therapeutic target for CA by targeting neovascularization in condyloma tissues.

Casticin suppresses self-renewal related stemness via miR-342-3p-mediated FoxM1 downregulation in cervical cancer cells

BackgroundCasticin (CAS), a natural flavonoid found in Viticis Fructus, Viticis Cannabifoliae Fructus, and Semen Euphorbiae, shows anti-inflammatory activity and efficacy against various cancers. However, its effect on stemness associated with self-renewal in cervical cancer (CC) cells remains unclear, as well as the underlying mechanism. PurposeThe primary objective of this study was to examine the effect of CAS on CC stemness and to explore the underpinning regulatory mechanism. MethodsHeLa cells underwent treatment with varying concentrations of CAS (0, 10, 30, 100 nM). To evaluate the impacts of CAS on CC stemness and tumorigenicity, sphere- and colony-formation assays and a xenograft model were employed. The study involved screening for changes in miRNAs and their target genes. The miRNA array identified an upregulation in miRNAs, whereas the mRNA array detected a downregulation of specific target genes. The latter genes were found to regulate stem cell-related genes through miR-342-3p in HeLa cells administered CAS. Next, whether miR-342-3p directly targets FOXM1 when upregulated by CAS was assessed by the luciferase reporter assay. qRT-PCR was performed to analyze miR-342-3p expression. Additionally, immunoblotting was conducted to assess the protein amounts of FoxM1 and stemness-related factors (CD133, CD49f, Nanog, and Sox2). Function rescue experiments were conducted to determine the mechanism of CAS in stemness regulation. These experiments involved utilizing a miR-342-3p inhibitor and overexpressing FOXM1 in HeLa cells. ResultsCAS decreased in vitro stemness, suppressing sphere- and colony-formation capabilities of CC. It also dose-dependently downregulated the expression of stemness-associated proteins, including CD133, CD49f, Nanog, and Sox2. Moreover, CAS inhibited in vivo carcinogenesis, remarkably reducing tumor growth in mice bearing HeLa cell xenografts. Analysis revealed downregulated FOXM1 expression in HeLa cells treated with CAS. In the luciferase reporter assay, miR-342-3p was found to directly target FOXM1 in CAS-treated HeLa cells. Additionally, miR-342-3p inhibitor transfection successfully rescued CAS’ suppressive impact on stemness. Furthermore, overexpression of FOXM1 did not induce changes in miR-342-3p expression. However, it effectively rescued CAS’ suppressive effects on stemness. Moreover, CAS also inhibited stemness, upregulated miR-342-3p, and lowered FOXM1 expression in the SiHa cell line. ConclusionCAS suppresses self-renewal-associated stemness by targeting FOXM1 via miR-342-3p upregulation. These findings suggest CAS is promising as a novel therapeutic candidate in CC.

Sesamol-mediated targeting of EPHA2 sensitises cervical cancer for cisplatin treatment by regulating mitochondrial dynamics, autophagy, and mitophagy.

Cervical cancer ranks as the fourth most prevalent cancer among women globally, presenting a significant therapeutic challenge due to its resistance to cisplatin. Ephrin type-A receptor 2 (EPHA2) is prominently overexpressed in cervical cancer and plays a vital role in cisplatin resistance, although the underlying mechanisms remain incompletely elucidated. Mitochondrial dynamics, autophagy, and mitophagy are critical in mediating cisplatin resistance. Sesamol, a phytochemical compound, has exhibited promising anticancer properties. This study aims to investigate the regulatory role of EPHA2 in these pathways underlying cisplatin resistance and to investigate the potential of sesamol in overcoming this resistance and inhibiting cervical cancer progression. In this study, we knocked down EPHA2 in the SiHa cell line and evaluated the resulting changes in molecular markers associated with mitochondrial dynamics, mitophagy, and autophagy. Our results indicated that EPHA2 knockdown (EPHA2-KD) led to enhanced mitochondrial fusion and reduced mitochondrial fission, mitophagy, and autophagy. Furthermore, we investigated the effect of EPHA2-KD and sesamol treatment on sensitising cervical cancer to cisplatin treatment. Our data revealed that EPHA2-KD and sesamol treatment significantly increases cellular sensitivity to cisplatin-induced cytotoxicity. Additionally, we demonstrated that sesamol effectively targets EPHA2, as evidenced by decreased EPHA2 expression levels following sesamol treatment. In summary, targeting EPHA2 through knockdown or sesamol treatment enhances cisplatin sensitivity in cervical cancer by modulating mitochondrial dynamics, autophagy and mitophagy, suggesting promising therapeutic strategies to overcome chemoresistance.

Untargeted metabolic analysis of Epaltes mexicana by LC-QTOF-MS: Terpenes with activity against human cancer cell lines

Epaltes mexicana is a plant widely used in traditional medicine and as a food in Mexico; however, its phytochemical and pharmacological studies are limited. This study aimed to identify the active secondary metabolites of Epaltes mexicana and determine its cytotoxic activity on cancer cell lines. Three organic extracts were obtained by maceration using n-hexane, dichloromethane, and methanol. The n-hexane extract was fractioned by simple column chromatography. Eight terpenes were annotated in collection 6 (C6) by LC-QTOF-MS using a gradient elution and Electrospray Ionization (ESI) in positive ion mode: 1) Gibberellin A15, 2) farfugin A, 3) dehydromyodesmone, 4) eremopetasitenin A1, 5) hydroxyisonobilin, 6) anhydrocinnzeylanine, 7) nigakilactone H and 8) taxodione. On the other hand, C6 showed a concentration-dependent cytotoxic effect on cancer cell lines MCF-7 (Emax = 74.69 ± 6.19 % and IC50 = 6.31 μg/mL), MDA-MB-231 (Emax = 79.28 ± 12.12 % and IC50 = 124.21 μg/mL), and SiHa (Emax = 82.96 ± 6.02 % and IC50 = 124.31 μg/mL). The C6 did not show a cytotoxic effect against DU-145 and non-cancerous cells from the mammary glands MCF-10A. These results indicate cytotoxic specificity on cancer cell lines and support the hypothesis that terpenes identified in E. mexicana must be investigated and developed for non-clinical and clinical trials as potential anti-cancer drugs.

Triptolide-induced cuproptosis is a novel antitumor strategy for the treatment of cervical cancer

BackgroundCuproptosis is a unique copper-dependent form of cell death that is highly correlated with the metabolic state of cells. Triptolide exerts pharmacological activity by altering the regulation of metal ions. Cuproptosis is poorly understood in cancer, so in this study, we explored whether triptolide could induce cuproptosis in cervical cancer cells.MethodsThe human cervical cancer cell lines HeLa and SiHa, which primarily rely on oxidative phosphorylation, were treated with triptolide. Cell viability, proliferation and migration, copper levels and cuproptosis-related protein levels were evaluated in these cell lines. The copper ion chelator tetrathiomolybdate (TTM) was administered to determine whether it could reverse the cuproptosis induced by triptolide. In addition, a nude mouse cervical cancer xenograft model was established to determine the effects of triptolide on cuproptosis in isolated tumor tissues.ResultsThe copper concentration increased with triptolide treatment. The levels of cuproptosis -related proteins, such as FDX1, LIAS, and DLAT, in the HeLa and SiHa cell lines decreased with triptolide treatment. XIAP, the target of triptolide, played a role in cuproptosis by regulating COMMD1. The level of copper exporters (ATP7A/B) decreased, but the level of the copper importer (CTR1) did not change with triptolide treatment. Furthermore, triptolide inhibited cervical cancer growth and induced cuproptosis in vivo.ConclusionsIn summary, we report a new antitumor mechanism by which triptolide disrupted intracellular copper homeostasis and induced cuproptosis in cervical cancer by regulating the XIAP/COMMD1/ATP7A/B axis.

Human papillomavirus-16 E6-positive cervical cancer attenuated by potent 2-(4-biphenylyl)-N-(1-ethyl-4-piperidinyl) acetamide second-generation analogs with improved binding affinity.

Human papillomavirus (HPV) infection, particularly HPV16, is a major contributor to the development of cervical cancer. Given the urgent need for novel therapeutic strategies targeting HPV-associated cancers, this study focuses on characterizing second-generation analogs of a lead compound, as a potential inhibitor of HPV16-E6. Protein-ligand docking, Gibbs binding free energy estimation, and molecular dynamics simulations were conducted. HPV16-infected SiHa and CaSki cell lines were used. MTT (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) assay for proliferation and flow cytometry for target inhibition and apoptosis were employed. Computational and cell proliferation analyses revealed that modifications to E6-855, particularly in the piperidinyl group, enhanced binding affinities against HPV16-E6, with E6-272 demonstrating superior binding properties. Molecular dynamics simulations confirmed the stable binding of E6-272 to HPV16-E6, supported by favorable binding energy estimates. E6-272 inhibited the proliferation of SiHa and CaSki cells with GI50 values of 32.56 and 62.09nM, respectively. The compound reduced HPV16-E6-positive population, while inducing the early and late phase apoptosis in these cells. Structural alterations at the piperidinyl group of E6-855 identified E6-272 as a promising inhibitor of HPV16-E6 with improved efficacy against HPV16-E6. Further experimental validation of E6-272 and its analogs warrant to advance its clinical utility in combating HPV-associated cancers.

SIRT4 Has an Anti-Cancer Role in Cervical Cancer by Inhibiting Glutamine Metabolism via the MEK/ERK/C-Myc Axis.

Glutamine metabolism is crucial in cell proliferation, aging, and apoptosis across various cancer types. Existing research indicates that Sirtuin 4 (SIRT4), primarily located in mitochondria, modulates this process. This study aimed to clarify the regulatory relationship between SIRT4 and glutamine metabolism in cervical cancer. SIRT4 mRNA levels and their clinical correlation to cervical cancer were analyzed using the UALCAN database. Immunohistochemistry (IHC) was performed to assess SIRT4 protein expression in tissue samples from cervical cancer patients. Transient transfection was employed to create Hela and Siha cell lines with overexpressed SIRT4, mitogen-activated extracellular signal-regulated kinase (MEK), and glutaminase 1 (GLS1). The impact on cellular functions was studied using MTT, soft agar, transwell, and western blotting assays. Glutamate and ATP levels were also measured to evaluate metabolic changes. Low levels of SIRT4 mRNA in cervical cancer tissues correlated with tumor metastasis and poor survival rates. Overexpression of SIRT4 led to suppressed cell proliferation, colony growth, and motility, along with significant down-regulation of GLS expression, a key contributor to glutamine metabolism. Additionally, SIRT4 overexpression resulted in the inactivation of the MEK/ERK/c-myc signaling pathway, while overexpression of MEK reversed these effects. Notably, the inhibitory effects of SIRT4 on cell proliferation, colony formation, migration, and invasion in Hela and Siha cells were significantly attenuated following GLS1 overexpression. SIRT4 acts as an anti-cancer agent in cervical cancer by inhibiting glutamine metabolism through the MEK/ERK/c-myc signaling pathway, providing a novel sight for cervical cancer therapy.

Synthesis and stabilization of anatase form of biomimetic TiO2 nanoparticles for enhancing anti-tumor potential

Abstract The present study emphasizes the stabilization of the biologically active anatase form of titanium dioxide (TiO2) nanoparticles (NP). TiO2 NP require stringent conditions for chemical synthesis and are usually a mixture of biologically inactive bulk rutile and the active bulk anatase forms. We utilized the culture pellet of the Exiguobacterium aestuarii SBG4 MH185868 to synthesize and stabilize the anatase form of TiO2 NP. The NP showed λ max at ∼350 nm and scanning electron microscope micrographs indicated their oval and spherical shape. Steric stabilized anatase TiO2 NP exhibited substantial cytotoxicity of up to 80% reduction in cell viability at 100 µg against cervical cancer derived HeLa and SiHa cell lines, whereas the rutile form showed least cytotoxicity. Clonogenic inhibition assay of HeLa cells showed dose-dependent decline with a 75% reduction in colony formation at 100 µg TiO2 NP and cell migration assay revealed significant inhibition in recovery of the wound/scratch in presence of anatase form of TiO2 NP (10–33% at 24 h and 42–79% at 48 h). Co-incubation of HeLa cells with anatase TiO2 NP in chorioallantoic membrane of embryonated chick eggs prevented the formation of new capillaries (20 ± 5% compared with control groups), indicating appreciable anti-angiogenic activity of the NP. Further, TiO2 NP tagged with doxorubicin and paclitaxel exhibited enhanced cytotoxicity against cancer cells at very low concentrations of 9 and 120 nM itself, indicating their anti-tumor potential. In conclusion, biomimetic anatase TiO2 NP have significant anti-proliferative and anti-angiogenic activity and can have potential application in tagging with generic anti-cancer drugs for enhanced cytotoxicity against cancer cells.

STAT5 Is Necessary for the Metabolic Switch Induced by IL-2 in Cervical Cancer Cell Line SiHa.

The tumor cells reprogram their metabolism to cover their high bioenergetic demands for maintaining uncontrolled growth. This response can be mediated by cytokines such as IL-2, which binds to its receptor and activates the JAK/STAT pathway. Some reports show a correlation between the JAK/STAT pathway and cellular metabolism, since the constitutive activation of STAT proteins promotes glycolysis through the transcriptional activation of genes related to energetic metabolism. However, the role of STAT proteins in the metabolic switch induced by cytokines in cervical cancer remains poorly understood. In this study, we analyzed the effect of IL-2 on the metabolic switch and the role of STAT5 in this response. Our results show that IL-2 induces cervical cancer cell proliferation and the tyrosine phosphorylation of STAT5. Also, it induces an increase in lactate secretion and the ratio of NAD+/NADH, which suggest a metabolic reprogramming of their metabolism. When STAT5 was silenced, the lactate secretion and the NAD+/NADH ratio decreased. Also, the expression of HIF1α and GLUT1 decreased. These results indicate that STAT5 regulates IL-2-induced cell proliferation and the metabolic shift to aerobic glycolysis by regulating genes related to energy metabolism. Our results suggest that STAT proteins modulate the metabolic switch in cervical cancer cells to attend to their high demand of energy required for cell growth and proliferation.

The Mechanism of HPV-mediated DNA Methylation in the Promoter Region of Long-chain Non-coding RNA MAGI2-AS3 in the Occurrence and Development of Cervical Cancer

Background: Cervical cancer, a malignancy of gynecological origin, typically necessitates a therapeutic approach combining surgery and chemoradiotherapy as the primary intervention. However, the 5-year survival rate remains suboptimal, prompting researchers to explore novel strategies for the early diagnosis and treatment of cervical cancer. This study delves into the investigation of human papillomavirus (HPV)-mediated DNA methylation modifications within the promoter region of the long non-coding RNA MAGI2-AS3 during cervical cancer development. This paper is an experimental study, laboratory based, using cell lines. Methods: A lentivirus overexpression vector encoding HPV16 E6/E7 proteins was established for transfecting cervical epithelial cells. The methylation status of DNA in the MAGI2-AS3 promoter region was assessed using MassARRAY, and the MAGI2-AS3 gene expression was measured through quantitative real time polymerase chain reaction (qRT-PCR). Subsequently, the correlation between methylation levels and gene expression in cervical cancer was analyzed. Results: (1) Relative to the HPV-negative cervical cancer cell line C33A, MAGI2-AS3 expression significantly decreased in the HPV-positive cervical cancer cell line Siha. (2) The methylation rate of 16 CpG sites in the HPV-positive cervical cancer cell line Siha was notably higher compared to the HPV-negative cervical cancer cell line C33A. (3) To further substantiate the regulatory impact on DNA methylation and expression within the MAGI2-AS3 promoter region, we silenced the expression of HPV16 E6 in the HPV-positive cervical cancer cell line Siha using HPV16 E6 siRNA. The ensuing qRT-PCR analysis revealed a significant up-regulation of MAGI2-AS3 expression in the HPV16 E6 siRNA group when contrasted with the negative control group. MassARRAY analysis was employed to gauge the DNA methylation levels in the promoter region of the MAGI2-AS3 gene in HPV-positive cervical cancer cells (Siha) following HPV16 E6 silencing. The results demonstrated a significantly lower methylation rate at the CpG_29 site in the HPV16 E6 siRNA group compared to the HPV16 E6 siRNA group. Conclusions: The study establishes a close association between HPV infection and elevated methylation levels coupled with diminished expression of MAGI2-AS3. The influence of HPV infection on the malignant transformation of cervical epithelial cells is potentially mediated through the regulatory modulation of MAGI2-AS3 expression via DNA methylation.

Bioinformatics Analysis of Human Papillomavirus 16 Integration in Cervical Cancer: Changes in MAGI-1 Expression in Premalignant Lesions and Invasive Carcinoma.

HPV 16 integration is crucial for the onset and progression of premalignant lesions to invasive squamous cell carcinoma (ISCC) because it promotes the amplification of proto-oncogenes and the silencing of tumor suppressor genes; some of these are proteins with PDZ domains involved in homeostasis and cell polarity. Through a bioinformatics approach based on interaction networks, a group of proteins associated with HPV 16 infection, PDZ domains, and direct physical interaction with E6 and related to different hallmarks of cancer were identified. MAGI-1 was selected to evaluate the expression profile and subcellular localization changes in premalignant lesions and ISCC with HPV 16 in an integrated state in cervical cytology; the profile expression of MAGI-1 diminished according to lesion grade. Surprisingly, in cell lines CaSki and SiHa, the protein localization was cytoplasmic and nuclear. In contrast, in histological samples, a change in subcellular localization from the cytoplasm in low-grade squamous intraepithelial lesions (LSIL) to the nucleus in the high-grade squamous intraepithelial lesion (HSIL) was observed; in in situ carcinomas and ISCC, MAGI-1 expression was absent. In conclusion, MAGI-1 expression could be a potential biomarker for distinguishing those cells with normal morphology but with HPV 16 integrated from those showing morphology-related uterine cervical lesions associated with tumor progression.

Identification of exosomal circSLC26A4 as a liquid biopsy marker for cervical cancer.

Circular RNA SLC26A4 (circSLC26A4) functions as an oncogene in the initiation and progression of cervical cancer (CC). However, the clinical role of plasma exosomal circSLC26A4 in CC is poorly known. This study aims to develop an accurate diagnostic method based on circulating exosomal circSLC26A4. In this study, exosomal circSLC26A4 derived from CC cell lines (CaSki, SiHa, and HeLa) and human cervical epithelial cells (HcerEpic) was measured and compared using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Additionally, 56 volunteers, including 18 CC patients, 18 cervical high-grade squamous intraepithelial lesion (HSIL) patients, and 20 healthy volunteers, were enrolled. qRT-PCR was also performed to measure the plasma exosomal circSLC26A4 levels in all participants. The exosomal circSLC26A4 expression level derived from CC cells was significantly elevated compared to it derived from HcerEpic cells. Plasma exosomal circSLC26A4 levels in CC patients were significantly higher than in healthy women and HSIL patients (P < 0.05). In addition, high plasma exosomal circSLC26A4 expression was positively associated with lymph node metastasis and FIGO stage (all P < 0.05). However, no significant correlation was found between plasma exosomal circSLC26A4 expression and age, intravascular cancerous embolus, and perineural invasion (P > 0.05). The high exosomal circSLC26A4 expression is closely related to the occurrence of CC. Plasma exosomal circSLC26A4 can be used as a diagnostic marker for CC.

GuiErBai: a potent inhibitor, exhibiting broadly antitumor effect against cervical cancer in vitro and in vivo.

Introduction: Cervical cancer (CC) ranks as the fourth most prevalent malignant tumor among women worldwide, and is the fourth leading cause of cancer-related mortality. GuiErBai (GEB), a compound preparation developed by our research team, is derived from the ancient Chinese medicine of the Miao nationality and is comprised of podophyllotoxin (PTOX), imperatorin, isoimperatorin, and A. dahurica alkaloids. These individual components have demonstrated notable efficacy in tumor treatment. However, the specific anti-tumor effect of the compound Chinese medicine GEB in the context of CC has yet to be validated. Methods: HeLa and SiHa cell lines were utilized for in vitro experiments and treated with 5mg/mL and 10mg/mL GEB concentrations, respectively. The cell cycle changes after GEB treatment were assessed using flow cytometry. Transmission electron microscopy was employed to observe autophagic bodies and apoptotic bodies, while MDC staining evaluated the occurrence of autophagy. CCK-8 was used to observe the effect of GEB on cell proliferation, and Transwell assays assessed cell migration and invasion. Western blotting detected cell cycle and apoptosis-related protein expression, along with the expression level of autophagy-related protein LC3I/II. Changes in ROS and mitochondrial membrane potential in cervical cancer cells following GEB treatment were determined using ROS detection and mitochondrial membrane potential detection kits. For the in vivo experiment, a nude mouse model of cervical cancer transplantation based on HeLa cells was established. Experimental animals were divided into negative control, positive control, high-dose GEB (10mg/mL), and low-dose GEB (5mg/mL) groups. Results: In HeLa and SiHa cell lines, the G0/G1 phase of tumor cells significantly decreased (p < 0.001), while the G2/M phase increased notably (p < 0.001) following various GEB treatments. Electron microscopy showed GEB promoted apoptotic body and autophagosome formation in both cell lines. Compared to untreated HeLa and SiHa cells, GEB-treated cells exhibited significantly reduced caspase3 protein expression, and substantially increased autophagy-related protein LC3I/II expression. GEB treatment significantly reduced migration and invasion capabilities in both cell lines (p < 0.001), while ROS content and mitochondrial membrane potential were significantly elevated (p < 0.001). GEB effectively inhibited cervical cancer cell proliferation, with the optimal concentration being 10mg/mL. A successful nude mouse model of cervical cancer transplantation was established using HeLa cells. Post-GEB treatment, the tumor volume and weight in nude mice significantly decreased (p < 0.001), with diminished expression of CD34, VEGF, and caspase3 proteins in tumor tissues. Discussion: GEB exhibits a robust antitumor effect against cervical cancer, both in vitro and in vivo, in a concentration-dependent manner, by regulating autophagy and apoptosis of tumor cells.

HPV16-miRNAs exert oncogenic effects through enhancers in human cervical cancer

BackgroundCervical cancer is a human papillomavirus (HPV)-related disease. HPV type 16 (HPV16), which is the predominant cause of cervical cancer, can encode miRNAs (HPV16-miRNAs). However, the role of HPV16-miRNAs in the pathogenesis of cervical cancer remains unclear.MethodsHuman cervical cancer cell lines SiHa (HPV16-positive) and C33A (HPV-negative), and cervical cancer tissues were collected to investigate the expression levels of two HPV16-miRNAs (HPV16-miR-H1 and HPV16-miR-H6). The overexpression and knockdown of HPV16-miR-H1 and HPV16-miR-H6 were performed using the lentiviral vector system and miRNA inhibitors, respectively. RNA-sequencing (RNA-seq) analysis and H3K27ac chromatin immunoprecipitation and sequencing (CHIP-seq) experiments were utilized to explore the roles of HPV16-miR-H1 and HPV16-miR-H6 facilitated by enhancers. CCK8, EdU, transwell, and wound healing assays were performed to verify the effects of HPV16-miR-H1 and HPV16-miR-H6 on cell proliferation and migration.ResultsHPV16-miR-H1 and HPV16-miR-H6 were highly expressed in both SiHa cells and tissue samples from HPV16-positive cervical cancer patients. RNA-seq analysis showed that HPV16-miR-H1 and HPV16-miR-H6 induced the upregulation of numerous tumor progression-associated genes. H3K27ac CHIP-seq experiments further revealed that HPV16-miR-H1 and HPV16-miR-H6 modulated the expression of critical genes by regulating their enhancer activity. The functional study demonstrated that HPV16-miR-H1 and HPV16-miR-H6 increased the migratory capacity of SiHa cells.ConclusionsOur data shed light on the role of HPV16-encoded miRNAs in cervical cancer, particularly emphasizing their involvement in the miRNA-enhancer-target gene system. This novel regulatory mechanism of HPV16-miRNAs provides new insights and approaches for the development of therapeutic strategies by targeting HPV16-positive cervical cancer.