Human Carcinoma Research Articles

The cytotoxic effect of 4 different wavelengths of Low-level laser therapy on squamous cell carcinoma – An invitro study

Background: Low-level laser therapy is a noninvasive method with the potential ability to change the balance of cell mediators and gene expressions. It affects cellular function resulting in beneficial clinical effects. This study aims to assess the effect of low-level light therapy (LLLT) using four different laser wavelengths on oral carcinoma cell viability in vitro. Methods and Material: HN5 human head and neck squamous cell carcinoma cell lines (HNSCC) were cultured and irradiated using four wavelengths of blue (485 nm), green (532nm), red (660 nm), and near Infra-red (810 nm) in a continuous mode with a dose of 1 J/cm2 (0.1W, 10sec) every 24hours for five consecutive days. Cell viability was assessed by evaluating mitochondrial activity by MTT assay. Results: All the wavelengths resulted in reduced viability of these cells compared to the controls. (P<0.05) There were statistically significant differences in cell viability between different wavelengths (P<0.001). The 810 nm laser irradiation showed the highest percentage of cell survival (55.92%) while 660 nm induced the lowest (36.02%). Conclusion: Different laser wavelengths may result in different effects on irradiated cells and red irradiation showed the lowest cell viability and the infrared laser had the highest cell viability results.

Thermosensitivity in HIKESHI Knockout Human Oral Squamous Cell Carcinoma HSC-3 Cells

Thermosensitivity in HIKESHI Knockout Human Oral Squamous Cell Carcinoma HSC-3 Cells

Renal cancer cells acquire immune surface protein through trogocytosis and horizontal gene transfer.

Trogocytosis is an underappreciated phenomenon that shapes the immune microenvironment surrounding many types of solid tumors. The consequences of membrane-bound proteins being deposited from a donor immune cell to a recipient cancer cell via trogocytosis are still unclear. Here, we report that human clear cell renal carcinoma tumors stably express the lymphoid markers CD45, CD56, CD14, and CD16. Flow cytometry performed on fresh kidney tumors revealed consistent CD45 expression on tumor cells, as well as varying levels of the other markers mentioned previously. These results were consistent with our immunofluorescent analysis, which also revealed colocalization of lymphoid markers with carbonic anhydrase 9 (CAIX), a standard kidney tumor marker. RNA analysis showed a significant upregulation of genes typically associated with immune cells in tumor cells following trogocytosis. Finally, we show evidence of chromosomal DNA being transferred from immune cells to tumor cells during trogocytosis. This horizontal gene transfer has transcriptional consequences in the recipient tumor cell, resulting in a fusion phenotype that expressed both immune and cancer specific proteins. This work demonstrates a novel mechanism by which tumor cell protein expression is altered through the acquisition of surface membrane fragments and genomic DNA from infiltrating lymphocytes. These results alter the way in which we understand tumor-immune cell interactions and may reveal new insights into the mechanisms by which tumors develop. Additionally, further studies into trogocytosis will help push the field towards the next generation of immunotherapies and biomarkers for treating renal cell carcinoma and other types of cancers.

Adherence and cytotoxicity of Acinetobacter baumannii on human cervical carcinoma epithelial cells: Exploring the role of anti-OmpA antibodies

We investigated the invasion of Acinetobacter baumannii strains to epithelial cells and elucidated the role of antibodies against outer membrane protein A (OmpA). A. baumannii ATCC 19606 and clinical isolate 58ST were utilized. OmpA was expressed, purified, and administered to BALB/c mice, inducing anti-OmpA antibodies. OmpA cytotoxicity was evaluated. Two A. baumannii strains were selected to infect human cervical HeLa cells. Serum resistance was determined at sera dilutions. Adhesion, internalization, and proliferation of live and killed A. baumannii in HeLa cells were examined with and without anti-OmpA sera. HeLa cell viability was assessed with and without exposure of live A. baumannii strains to anti-OmpA sera. Cytoskeleton inhibitor experiments were conducted on epithelial cells to probe microfilament and microtubule involvement in A. baumannii invasion. OmpA prompted antibody production without toxicity in mice. A. baumannii strains displayed varying cell invasion abilities, notably the clinical strain exhibiting the highest invasion. A. baumannii cells localized within vacuoles during internalization, migrating towards the nucleus, using a zipper-like invasion process. Bacterial proliferation within host cells led to HeLa cell death. Pre-treatment with anti-OmpA antibodies significantly curbed adhesion and invasion of A. baumannii in HeLa cells. Microscopic imaging provided proof of the intracellular presence of A. baumannii in HeLa cells. In conclusion, the OmpA plays a crucial part in A. baumannii - epithelial cell interactions. The results add to our knowledge of pathogenesis during the initial stages of infection by A. baumannii.

Gossypol Inhibits Metastasis of Lung Cell Carcinoma by Reversing Epithelial to Mesenchymal Transition and Suppressing Proteases Activity.

Gossypol, a natural polyphenolic compound, possesses antivirus activity and induces cell death of different types of tumors. However, the efficacy of gossypol on lung carcinoma metastases and epithelial to mesenchymal transition remains unknown. The aim of the present work was to determine the cellular and molecular mechanism of the anti-cancer and anti-metastatic efficacies of gossypol on human lung carcinoma cells. Gossypol showed a marked suppression of the viability, motility, and invasion in H1299 and A549 cells. Zymography assay showed that gossypol was sufficient to suppress the activities of urokinase-type plasminogen activator and matrix metalloproteinase-2. Gossypol reversed TGF-β-induced epithelial to mesenchymal transition. Gossypol reduced vimentin, p-FAK, p-Src and p-paxillin. In vivo studies of gossypol were performed using subcutaneous inoculation and tail vein injection of A549 into immunodeficient BALB/c nude mice and severe combined immunodeficient mice.

PRC1 Protein Subcomplexes Architecture: Focus on the Interplay between Distinct PCGF Subunits in Protein Interaction Networks.

The six PCGF proteins (PCGF1-6) define the biochemical identity of Polycomb repressor complex 1 (PRC1) subcomplexes. While structural and functional studies of PRC1 subcomplexes have revealed their specialized roles in distinct aspects of epigenetic regulation, our understanding of the variation in the protein interaction networks of distinct PCGF subunits in different PRC1 complexes is incomplete. We carried out an affinity purification mass spectrometry (AP-MS) screening of three PCGF subunits, PCGF1 (NSPC1), PCGF2 (MEL18), and PCGF4 (BMI1), to define their interactome and potential cellular function in pluripotent human embryonal carcinoma cell "NT2". The bioinformatic analysis revealed that these interacting proteins cover a range of functional pathways, often involved in cell biology and chromatin regulation. We also found evidence of mutual regulation (at mRNA and protein level) between three distinct PCGF subunits. Furthermore, we confirmed that the disruption of these subunits results in reduced cell proliferation ability. We reveal an interplay between the compositional diversity of the distinct PCGF containing PRC1 complex and the potential role of PCGF proteins within the wider cellular network.

Novel copper-drugs bearing dipodal bis-mercaptobenzimidazoles: Synthesis, crystal structures, in vitro biological activities, DNA binding, DFT calculations and molecular docking

Three novel copper(II) complexes, 1–3, bearing dipodal bis-mercaptobenzimidazole derivatives based on ortho-, meta- or para-xylene (L1, L2, and L3) were successfully prepared and characterized by using various spectral techniques, including elemental analysis, FT-IR, 1H NMR, and UV–Vis spectroscopy, LC-MS spectrometry and TGA. The analysis revealed that the ligand/metal molar ratio in all copper(II) complexes is 1:1 and the ligand coordinates as a neutral N-donor onto metal center. Additionally, the crystal structures of L1, L2, L3, and copper(II) complex 2 were determined using single crystal X-ray diffraction (SC-XRD) analysis. Copper(II) complexes 1–3 displayed significant stability at pH range of 4–10. The antibacterial effect of ligands and complexes was tested against both gram-negative (Escherichia coli, E. coli ATCC 25922 PTCC 1399) and gram-positive (Staphylococcus aureus, S. aureus ATCC 6538 PTCC 1112) bacterial strains. It should be noted that the complexes showed enhanced antibacterial activity (up to 99 %) when compared to their free ligands. The in vitro studies of all synthesized compounds consisted of testing them against the human colorectal carcinoma cancer cell line (HCT-116) using the MTT assay. The findings revealed that the copper(II) complexes exhibited lower CC50 values (CC50 ranging from 0.045 mM to 0.135 mM) compared to their corresponding ligands (CC50 ranging from 0.150 mM to 0.240 mM) and carboplatin (CC50 = 0.165 mM), indicating higher anticancer activity of the complexes. Additionally, DAPI staining and fluorescence spectroscopy (at three different temperatures) were performed to further examine the impact of complexes 1–3 on inducing apoptosis and to explore their interaction with DNA, respectively. The results revealed a dynamic quenching mechanism, with hydrophobic forces playing a dominant role in the binding process. The viscosity measurements indicated that all complexes could interact in a groove binding manner with DNA. Density functional theory (DFT) calculations were employed to support the structural and vibrational studies and to predict the chemical reactivity. Docking simulations were conducted to evaluate their behavior of the synthesized compounds towards DNA (PDB: 1BNA). These results suggested that various elements, including NH groups, imidazole rings, thioetheric sulfur atom and sulfate moieties of ligands and complexes, are involved in groove binding with DNA.

Establishment and biological characteristics of a human buccal mucosa squamous cell carcinoma cell line SCC117

Objective: To establish a human buccal mucosa squamous cell carcinoma (BMSCC) cell line SCC117 in China, analyze and identify its basic biological characteristics. Methods: A 59-year-old Chinese male patient with BMSCC in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology in January 2011 was included in this study, his surgical specimens were primary cultured in vitro by improved tissue block culture method. The BMSCC cell line SCC117 was established after continuous passage and stable growth. The morphological characteristics of the cells were observed by light and electron microscope, and their basic biological characteristics were analyzed by growth curve, chromosome karyotype and xenotransplantation tumorigenicity in nude mice experiment. The expressions of cytokeratin (CK14), tumor-related proteins retinoblastoma tumor suppressor protein (RB), P53, E-cadherin, P21, phosphatase and tensin homolog deleted on chromosome ten (PTEN) were detected by immunohistochemical and human papilloma virus (HPV) were tested by PCR. SCC117 was identified by short tandem repeat (STR) analysis of genomic DNA. Results: SCC117, a human BMSCC cell line, had been continuously subcultured in vitro for more than 150 generations. The cells grew in polygonal mosaic and lost contact inhibition, the typical desmosomes and tensional fibrils were observed by electron microscope, and CK14 was positive by immunohistochemistry. The doubling time was 40.16 h, the chromosome mode of the cell line was concentrated between 67 and 69, hypo-triploid. All 4 nude mice inoculated with SCC117 cells developed tumors, indicating that the SCC117 cell line had the ability of xenogeneic tumorigenesis. The histopathological type of the transplanted tumor in nude mice was consistent with that of the primary tumor tissue, both of which were squamous cell carcinoma. The immunohistochemical results showed that in both human primary tumor and the transplanted tumor tissue in nude mice, RB, P53, and E-cadherin were all positive, P21 was weakly positive, while PTEN was negative. SCC117 was tested negative for the presence of HPV. STR sequence analysis showed that SCC117 cell line originated from primary tumor tissue and was not cross-contaminated by other cell lines. Conclusions: The human BMSCC cell line SCC117 was successfully established in China, which could provide a new experimental model for the study of oral SCC without HPV infection, especially BMSCC.

Synthesis, molecular docking, dynamics study and preliminary cytotoxicity study of some coumarin linked imidazothiadiazoles

A new series of coumarin-linked imidazo[2,1-b][1,3,4]thiadiazoles were synthesized and evaluated for their cytotoxicity inhuman T-lymphocyte (CEM), human cervix carcinoma (HeLa) and murine leukemia cells (L1210). Among the tested compounds, 3-[5‑bromo-2-(thiophen-2-ylmethyl)imidazo[2,1-b][1,3,4]thiadiazol-6-yl]-2H-chromen-2-one 9b exhibited cytotoxicity at 0.77 μM against CEM, 1.6 μM against L1210 and 0.38 μM against HeLa cells. Compound 6-(2-oxo-2H-chromen-3-yl)-2-(thiophen-2-ylmethyl)imidazo[2,1-b][1,3,4]thiadiazol-5-carbaldehyde 10b showed cytotoxicity at 3.5 μM against CEM and at 9.5 μM against HeLa cells. Further, molecular docking simulations performed to evaluate the possibility of these synthesized analogs as inhibitors of heat shock protein 90 (Hsp90), Pdb ID: 1UYL revealing that docking predictions are in good agreement with in-vitro results (-10.7 for 9b and -10.5 for 10b). The in-silico ADME parameters, pharmacokinetics and drug-likeness of all derivatives were examined in detail using the Swiss ADME webserver. By applying molecular dynamics simulation experiments a better stability was observed of compounds 8b, 9a, 10b and 11b.

Preparation of Composite Hydrogels Based on Cysteine-Silver Sol and Methylene Blue as Promising Systems for Anticancer Photodynamic Therapy.

In this study, a novel supramolecular composite, "photogels", was synthesized by mixing of cysteine-silver sol (CSS) and methylene blue (MB). A complex of modern physico-chemical methods of analysis such as viscosimetry, UV spectroscopy, dynamic and electrophoretic light scattering, scanning electron microscopy and energy-dispersive X-ray spectroscopy showed that MB molecules are uniformly localized mainly in the space between fibers of the gel-network formed by CSS particles. Molecules of the dye also bind with the surface of CSS particles by non-covalent interactions. This fact is reflected in the appearance of a synergistic anticancer effect of gels against human squamous cell carcinoma even in the absence of light irradiation. A mild toxic influence of hydrogels was observed in normal keratinocyte cells. Photodynamic exposure significantly increased gel activity, and there remained a synergistic effect. The study of free-radical oxidation in cells has shown that gels are not only capable of generating reactive oxygen species, but also have other targets of action. Flow cytometric analysis allowed us to find out that obtained hydrogels caused cell cycle arrest both without irradiation and with light exposure. The obtained gels are of considerable interest both from the point of view of academics and applied science, for example, in the photodynamic therapy of superficial neoplasms.

Molecular Insights into the Anticancer Activity of Withaferin-A: The Inhibition of Survivin Signaling.

Survivin, a member of the IAP family, functions as a homodimer and inhibits caspases, the key enzymes involved in apoptosis. Several Survivin inhibitors, including YM-155, Debio1143, EM1421, LQZ-7I, and TL32711, have emerged as potential anticancer drugs awaiting validation in clinical trials. Due to the high cost and adverse side effects of synthetic drugs, natural compounds with similar activity have also been in demand. In this study, we conducted molecular docking assays to evaluate the ability of Wi-A and Wi-N to block Survivin dimerization. We found that Wi-A, but not Wi-N, can bind to and prevent the homodimerization of Survivin, similar to YM-155. Therefore, we prepared a Wi-A-rich extract from Ashwagandha leaves (Wi-AREAL). Experimental analyses of human cervical carcinoma cells (HeLa and ME-180) treated with Wi-AREAL (0.05-0.1%) included assessments of viability, apoptosis, cell cycle, migration, invasion, and the expression levels (mRNA and protein) of molecular markers associated with these phenotypes. We found that Wi-AREAL led to growth arrest mediated by the upregulation of p21WAF1 and the downregulation of several proteins (CDK1, Cyclin B, pRb) involved in cell cycle progression. Furthermore, Wi-AREAL treatment activated apoptosis signaling, as evidenced by reduced PARP-1 and Bcl-2 levels, increased procaspase-3, and elevated Cytochrome C. Additionally, treating cells with a nontoxic low concentration (0.01%) of Wi-AREAL inhibited migration and invasion, as well as EMT (epithelial-mesenchymal transition) signaling. By combining computational and experimental approaches, we demonstrate the potential of Wi-A and Wi-AREAL as natural inhibitors of Survivin, which may be helpful in cancer treatment.

Stable Cyclometallated Palladium Complexes of Arylamides: Synthesis, Redox and Anticancer Activities

AbstractAir‐stable cyclometalated palladium(II) complexes with benzamide ligands were synthesized in high yields and characterized by X‐ray diffraction analysis, CVA, 1H NMR, 13C NMR spectroscopy, MALDI‐MS, and ESI‐MS. The electrochemical oxidation of the complexes is reversible in the presence of a quinoline substituent in the ligand and gives Pd (III) species that do not undergo reductive elimination and are detectable by ESR spectroscopy. The complexes showed high cytotoxicity against cervical cancer (M‐HeLa) and duodenal adenocarcinoma (HuTu 80), a human mammary ductal adenocarcinoma line (MCF‐7) and a human lung carcinoma cell line (A549). The possibility of generating reactive oxygen species in solution (such as OH−radicals), which can be responsible for the antitumor activity of the studied complexes, using the ESR method was shown.

Unraveling the molecular basis for effective regulation of integrin α5β1 for enhanced therapeutic interventions

Cell attachment to the extracellular matrix significantly impacts the integrity of tissues and human health. The integrin α5β1 is a heterodimer of α5 and β1 subunits and has been identified as a crucial modulator in several human carcinomas. Integrin α5β1 significantly regulates cell proliferation, angiogenesis, inflammation, tumor metastasis, and invasion. This regulatory role of integrin α5β1 in tumor metastasis makes it an appealing target for cancer therapy. The majority of the drugs targeting integrin α5β1 are limited only to clinical trials. In our study, we have performed 94287 compounds screening to determine potential drugs against α5β1 integrin. We have used ATN-161 as a reference and employed combined bioinformatic methodologies, including molecular modelling, virtual screening, MM-GBSA, cell-line cytotoxicity prediction, ADMET, Density Functional Theory (DFT), Non-covalent Interactions (NCI) and molecular simulation, to identify putative integrin α5β1 inhibitors. We found Taxifolin, PD133053, and Acebutolol that possess inhibitory activity against α5β1 integrin and could act as effective drug for the cancer treatment. Taxifolin, PD133053, and Acebutolol exhibited excellent binding to the druggable pocket of integrin α5β1, and also maintained a unique binding mechanism with extra hydrophobic contacts at molecular level. Overall, our study gives new pharmacological candidates that may act as a potential drug against integrin α5β1.

Modulation with anti-Oma87 antibodies of cytotoxicity, adherence, and internalization of Acinetobacter baumannii in human cervical carcinoma epithelial cells.

BamA, an Omp85 superfamily member, is universally conserved and essential for cell viability. Using anti-Oma87 antibodies, we focus on understanding the effect of Oma87 of Acinetobacter baumannii on pathogenicity. Oma87 was expressed, purified, and used to induce anti-Oma87 antibodies in BALB/c mice. Acute toxicity of the protein was evaluated in mice. HeLa cells were infected with both live and killed A. baumannii 19606 and a clinical isolate. The effects of anti-Oma87 sera on A. baumannii adherence, internalization, and proliferation in HeLa cells were studied. The roles of microfilaments and microtubules in A. baumannii invasion were demonstrated by Actin disruption. Reduced bacterial population and biofilm formation were noted. The ability of A. baumannii to provoke autophagy through Oma87 induction leads to incomplete autophagy and potentially facilitates bacterial replication. Actin-mediated uptake, attachment, and invasion demonstrated A. baumannii survival and multiplication within vacuoles in the host cell. The findings underscore the potential of Oma87 as a therapeutic intervention target in infections caused by A. baumannii. This comprehensive analysis contributes valuable information for understanding the virulence mechanisms of A. baumannii, potentially guiding future strategies to combat infections caused by this pathogen.

Temporal and spatial resolution of magnetosome degradation at the subcellular level in a 3D lung carcinoma model

Magnetic nanoparticles offer many exciting possibilities in biomedicine, from cell imaging to cancer treatment. One of the currently researched nanoparticles are magnetosomes, magnetite nanoparticles of high chemical purity synthesized by magnetotactic bacteria. Despite their therapeutic potential, very little is known about their degradation in human cells, and even less so of their degradation within tumours. In an effort to explore the potential of magnetosomes for cancer treatment, we have explored their degradation process in a 3D human lung carcinoma model at the subcellular level and with nanometre scale resolution. We have used state of the art hard X-ray probes (nano-XANES and nano-XRF), which allow for identification of distinct iron phases in each region of the cell. Our results reveal the progression of magnetite oxidation to maghemite within magnetosomes, and the biosynthesis of magnetite and ferrihydrite by ferritin.Graphical

Polyvinyl Alcohol Capped Silver Nanostructures for Fortified Apoptotic Potential Against Human Laryngeal Carcinoma Cells Hep-2 Using Extremely-Low Frequency Electromagnetic Field.

: Polyvinyl alcohol-capped silver nanostructures (cAgNSs) were investigated in order to enhance the cytotoxicity, pro-apoptotic, and oxidant patterns of in human laryngeal carcinoma Hep-2 cells by employing a 50 mT electromagnetic field (LEMF) for 30 min. Wet chemical reduction was used to synthesize the cAgNSs, and after they had been capped with polyvinyl alcohol, they were specifically examined for particle size analysis and structural morphology. To visualize how the silver may attach to the protein targets, a molecular docking study was conducted. Estimation of cytotoxicity, cell cycle progression supported by mRNA expression of three apoptotic-promoting genes and one apoptotic-resisting. Particle size analysis results were a mean particle size of 157.3±0.5 nm, zeta potential value of -29.6 mV±1.5 mV, and polydispersity index of 0.31±0.05. Significantly reduction of IC50 against Hep-2 cells by around 6-fold was concluded. Also, we obtained suppression of the proliferation of Hep-2 cells, especially in the G0/G1 and S phases. Significant enhanced mRNA expression revealed enhanced induced CASP3, p53, and Beclin-1 mediated pro-apoptosis and induced NF-κB mediated autophagy in Hep-2 cells. Augmented levels of GR, ROS and MDA as oxidative stress biomarkers were also obtained. HE staining of Hep-2 cells exposed to cAgNSs and LEMF confirmed the enhanced apoptotic potential comparatively. By conclusion, the developed nano-sized structures with the aid of extremely-low frequency electromagnetic field were successful to fortify the anti-cancer profile of cAgNSs in Hep-2 cells.

Dendritic cells and vascular endothelial growth factor-C in human oral squamous cell carcinoma

ObjectiveDendritic cells (DCs) are antigen-presenting cells that can activate naive T cells and thus play a role in tumor immunity. Vascular endothelial growth factors (VEGFs) produced and secreted by various cancers have been reported to inhibit DC differentiation from progenitor cells. However, the relationship between VEGF-C and DCs in oral squamous cell carcinoma (OSCC) remains unclear. MethodsFormalin-fixed paraffin-embedded samples of 172 OSCCs were studied. Immunohistological staining was performed to determine the density of S100- and CD1a- positive DCs, D2–40-positive lymphatic vessels, and the grade of VEGF-C expression in OSCCs. OSCC cell lines were cultured and examined for VEGF-C secretion using ELISA. ResultsIn comparison to pathological lymph node-negative (PN-) cases, the density of DCs in cancer tissues was significantly lower in PN-positive (PN+) cases, whereas the lymphatic vessel density of cancer tissues was significantly higher in PN+ cases. The density of DCs decreased significantly with increasing VEGF-C expression, indicating a weak inverse relationship. There was a strong positive correlation between VEGF-C expression and lymphatic vessel density. ELISA revealed VEGF-C secretion in various OSCC cell lines, particularly HSC-3, and this increased over time. ConclusionsThese results indicate that VEGF-C expressed by OSCC may increase lymphangiogenesis and create an environment that promotes lymph node metastasis.

The association between infectious agents and breast cancer: a review of the epidemiologic evidence.

Several viruses have been casually linked to human cancers, including cervical, nasopharyngeal, liver, sarcoma, and Merkel cell carcinomas. However, the etiologic contribution of viral infections to breast cancer, the number one incident cancer among women worldwide, is not well established. Among studies exploring associations of viruses with breast cancer, potential linkages have been identified between breast cancer and five viruses: beta retrovirus, (i.e., mouse mammary tumor virus), human papillomavirus, Epstein Barr virus. bovine leukemia virus, and human cytomegalovirus. In this review, we provide a comprehensive evaluation of epidemiological ecologic, case-control, case-only, and cohort studies investigating these associations. Wediscuss results from several existing reviews and meta-analyses, evaluate epidemiological studies published in the past five years, and assess the relationship between these viruses and breast tumor clinicopathological factors. The strongest epidemiological evidence for a viral role in breast cancer exists for MMTV and HPV, though limitations include lack of prospective studies for MMTV and potential detection bias in HPV studies. Viral detection challenges have limited studies of EBV and HCMV. Fewer studies have evaluated BLV, and though it has been associated with higher risk of breast cancer, sample sizes are quite small. CONCLUSION: While epidemiologic evidence exists for an association between these five viruses and breast cancer, various methodological issues and lack of prospective studies preclude robustconclusions. Future research should prioritize establishing a temporal relationship between infection and disease, minimizing misclassification of detection assays, and further exploring the influence of co-infections.

Antihypertensive agent losartan promotes tongue squamous cell carcinoma cell proliferation via EGFR/ERK1/2/cyclin D1 signaling axis

ObjectiveTo study the effects of losartan, an angiotensin II receptor blocker, in the SCC4 and SCC25 human tongue squamous cell carcinoma cell lines. MethodsCell proliferation was measured by MTS/PMS activity and trypan blue exclusion assays. The levels of the cell proliferation marker, cyclin D1, were analyzed by western blotting. Apoptosis was assessed by caspase-3 activation and Annexin V-FITC/propidium iodide double staining. Activation of epidermal growth factor receptor (EGFR) and ERK1/2 was validated by western blotting. ResultsModerate concentrations of losartan enhanced the proliferation of SCC4 and SCC25 cells. However, high losartan concentrations induced apoptosis in SCC4 cells. Losartan activated the EGFR/ERK1/2/cyclin D1 signaling axis, which in turn promoted cell proliferation. Afatinib (EGFR inhibitor) and U0126 (ERK1/2 inhibitor) abolished losartan-induced cell proliferation. In contrast, UC2288 (p21 inhibitor) enhanced it. ConclusionsLosartan exhibited dual effects on tongue squamous cell carcinoma cells. Moderate losartan concentrations facilitated cell proliferation, whereas high concentrations induced cytotoxicity in tongue carcinoma cells.

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ON THE BACK COVER: DA‐Raf inhibits ERK activation, resulting in the suppression of collective cell migration and invasion of KRAS‐mutant cancer cells. In human pancreatic carcinoma MIA PaCa‐2 cells, phospho‐ERK1/2 (magenta) is suppressed by the expression of EGFP‐DA‐Raf (green). EGFP‐DA‐Raf is concentrated on the plasma membrane.Credit: Aoi Matsuda and Takeshi Endo (Chiba University, Japan) image