Squamous Cell Lines Research Articles

Long non-coding RNA CCAT1/miR-218/ZFX axis modulates the progression of laryngeal squamous cell cancer.

Long non-coding RNAs have been proved to be closely associated with different cancers. This study was designed to elucidate the function and mechanisms of colon cancer-associated transcript-1 in the progression of human laryngeal squamous cell cancer. Expressions of colon cancer-associated transcript-1, microRNA-218, and zinc finger protein, X-linked messenger RNA were measured using quantitative real-time polymerase chain reaction, and the expression level of zinc finger protein, X-linked protein was detected using western blot. Proliferation and invasion of laryngeal squamous cell cancer cell lines were detected by Cell Counting Kit-8 assay and Transwell invasion assay, respectively. Luciferase assay was used to confirm whether microRNA-218 is a target of colon cancer-associated transcript-1 and whether microRNA-218 directly binds to 3'-untranslated region of zinc finger protein, X-linked messenger RNA. Effect of colon cancer-associated transcript-1 on tumor growth was observed through xenograft mice models in vivo. The results showed that expressions of colon cancer-associated transcript-1 and zinc finger protein, X-linked were significantly higher while microRNA-218 expression was significantly lower in the laryngeal squamous cell cancer tissues than those in the adjacent normal tissues. MicroRNA-218 overexpression or zinc finger protein, X-linked silencing significantly suppressed proliferation and invasion of laryngeal squamous cell cancer cells. Moreover, knockdown of colon cancer-associated transcript-1 significantly inhibited proliferation and invasion of laryngeal squamous cell cancer cells, which were reversed by microRNA-218 downregulation or zinc finger protein, X-linked upregulation. Finally, colon cancer-associated transcript-1 silencing inhibited xenograft tumor growth of laryngeal squamous cell cancer in vivo. In conclusion, colon cancer-associated transcript-1 knockdown inhibits proliferation and invasion of laryngeal squamous cell cancer cells through enhancing zinc finger protein, X-linked by sponging microRNA-218, elucidating a novel colon cancer-associated transcript-1-microRNA-218-zinc finger protein, X-linked regulatory axis in laryngeal squamous cell cancer and providing a promising therapeutic target for laryngeal squamous cell cancer patients.

Cell line dependent expression of EpCAM influences the detection of circulating tumor cells with CellSearch.

ObjectivesThe existence of circulating tumor cells has emerged as an important factor for prognosis and survival. The CellSearch method is the only circulating tumor cell detection method approved by the US Food and Drug Administration for clinical use. It relies on the detection of EpCAM (epithelial cell adhesion molecule) and is approved for colon cancer, breast cancer and prostate cancer. We now investigated whether CellSearch can be used to quantify circulating tumor cells in head and neck squamous cell cancer.Study Design and MethodsIn this study, we investigated the expression of EpCAM in 12 head and neck squamous cell cancer cell lines using Western blot and how this affected their detectability with CellSearch in peripheral blood.ResultsWe found a great variation in the expression of EpCAM between our head and neck squamous cell cancer cell lines. This was accompanied by variations in counting efficiency.ConclusionWe suggest that for reliable quantification of circulating tumor cells in blood from patients with head and neck squamous cell cancer cell, an epitope independent method is preferable.Level of EvidenceNA

The PI3K-Akt signaling leads to synergy of erlotinib and crizotinib in wild-type NSCLC.

e20043 Background: Targeted therapies caused a revolution in treatment of non-small cell lung cancer (NSCLC). Response to Epidermal Growth Factor Receptor such as erlotinib, can be predicted by the presence of sensitizing mutations in EGFR. In case of cMET, amplification or exon 14 skipping serve as biomarkers for response to cMET-TKIs, crizotinib. Methods: In this study, we investigated the combination of erlotinib and crizotinib on several squamous NSCLC cell lines wild-type for EGFR and cMET. Growth inhibition was determined using the sulforhodamine B-assay. Combination indexes (CI) were calculated based on the method of Chou and Talalay. A CI below 0.8 was considered synergistic, between 0.8 and 1.2 was considered additive and above 1.2 was considered antagonistic. The influence of treatment on the cell cycle, cell migration, 3D cell cultures and phosphorylation was studied. Results: The H1703 cell line gave an antagonistic (CI = 1.20±0.15), the Calu1 (CI = 0.81±0.04), H520 (CI = 0.87±0.06) and SKMES1 (CI = 0.81±0.02) were additive and LUDLU (CI = 0.39±0.07) was synergistic. A G1 phase arrest occurred after treatment with erlotinib (38 to 76%), whereas crizotinib caused a G2/M phase arrest (13 to 64%). In the combination, the effect of crizotinib was dominant (13 to 52%). A decrease in p-ERK1/2 (Thr202/204), p-PRAS40 (Thr246) and p-GSK3 β (Ser9) was observed. Phospho-PRAS40 showed a decrease after treatment with erlotinib or crizotinib, whereas combination treatment almost abolished p-PRAS40. In the SKMES1 cell line, p-PRAS40 only decreased after the combination, whereas H1703 cells showed no change in p-PRAS40 levels. Phospho-PRAS40 activity is strongly linked to PI3K/Akt signaling. Her3 is able to heterodimerize both with EGFR and cMET, thus activating downstream PI3K/Akt signaling. No expression of Her3 in the antagonistic cell line was detected. In the LUDLU, levels of p-Her3 were not detectable after erlotinib treatment and in the combination, whereas in the SKMES1 levels of p-Her3 slightly decreased only after combination treatment. Conclusions: To conclude, the simultaneous inhibition of both EGFR and cMET leads to a strong inhibition of PI3K/Akt signaling, leading to synergy in the LUDLU wild-type squamous NSCLC cells.

Results of a phase II randomized controlled clinical trial comparing efficacy of cabazitaxel versus docetaxel as second-line or above therapy in recurrent head and neck cancer.

6018 Background: Cabazitaxel has shown activity in squamous cancer cell lines and in taxane resistant cell lines. Hence we planned a randomized phase 2 study to evaluate the efficacy and safety of cabazitaxel against docetaxel in recurrent head and neck cancer, post first line treatment. Methods: This was a phase 2 open label, investigator initiated, randomized controlled trial of Docetaxel (75 mg/m2) versus Cabazitaxel (20 mg/m2), in adult patients with head and neck cancer, ECOG performance status 0-2, with measurable disease, who have been exposed to at least one line of chemotherapy (CTRI/2015/06/005848). 1:1 central randomization was performed and chemotherapy was administered till progressive disease or until patient had intolerable side effects. The sample size of 92 (46 per group) was determined based on an assumption for a difference in disease control rate of 25%, an alpha of 0.05 and 80% power. The data was censored for analysis on 3rd March 2017. Primary analysis of disease control at 6 weeks (CR/PR/SD) was assessed and compared using the chi-square test. Progression free survival (PFS) and overall survival (OS) curves were estimated using the Kaplan-Meier method. Cox proportional hazard model was used for comparison of PFS and OS between the 2 arms. Results: 92 patients were accrued in the study with 46 in each arm. The disease control rate at 6 weeks was better in the docetaxel arm which was statistically significant over the cabazitaxel arm (13.6% versus 52.3%, p = 0.017). The median PFS was 21 days (95% CI 5.28-36.72 days) in the cabazitaxel arm versus 61 days (95% CI 16.21 to 105.79 days) in the docetaxel arm (HR = 1.466, 95% CI 0.923-2.328, p = 0.105). The median OS was 172 days (95% CI 111.78 to 232.22 days) in the cabazitaxel arm versus 188 days (95% CI 134.4 to 241.6 days) in the docetaxel arm (HR-1.408, 95% CI 0.738-2.688, p = 0.299). Conclusion: In this phase 2 study, docetaxel had a superior disease control rate at 6 weeks and PFS compared to cabazitaxel. Clinical trial information: CTRI/2015/06/005848.

Interferon regulatory factor 4 (IRF4) is overexpressed in human non‑small cell lung cancer (NSCLC) and activates the Notch signaling pathway.

The transcription factor, interferon regulatory factor 4 (IRF4), serves an essential role in the regulation of immune responses, and has been reported to act as a diagnostic and prognostic marker for various hematological malignancies. The present study aimed to investigate whether IRF4 could exert effects on human non-small cell lung cancer (NSCLC) and to explore the underlying mechanism. The mRNA and protein expression of IRF4 was detected in NSCLC tissues using reverse-transcription quantitative polymerase chain reaction and western blotting, respectively. In the in vitro experiment, IRF4 expression was knocked down or overexpressed using lentivirus in human lung adenocarcinoma A549 and lung squamous cell carcinoma LC-AI cell lines. Cell proliferation and colony number were analyzed using MTT and colony formation assays, respectively. The expression levels of IRF4 mRNA and protein were significantly higher in NSCLC tissues (n=54) compared with that in adjacent non-tumor tissues. Similarly, the expression levels of Notch1 and Notch2 mRNA were significantly higher in NSCLC tissues. Furthermore, the expression level of IRF4 mRNA was positively correlated with the levels of Notch1 and Notch2 mRNA in NSCLC tissues. Consequently, using NSCLC cell lines, it was demonstrated that the knockdown of IRF4 expression significantly reduced the cell proliferation rate and colony formation, whereas IRF4-overexpression significantly increased them. Notably, the IRF4 knockdown significantly decreased the expression levels of Notch1 and Notch2 mRNA, and phosphorylated protein kinase B (AKT), whereas IRF4 overexpression resulted in the opposite. The results of the present study indicate that IRF4 is overexpressed and serves as a tumor promoter in human NSCLC, at least partially, through activating the Notch-Akt signaling pathway.

Sulfiredoxin May Promote Cervical Cancer Metastasis via Wnt/β-Catenin Signaling Pathway.

The abnormal elevation of sulfiredoxin (Srx/SRXN1)—an antioxidant enzyme whose main function is to protect against oxidative stress—has been shown to be closely correlated with the progression of several types of cancer, including human cervical cancer. However, the molecular mechanism by which Srx promotes tumor progression, especially cancer metastasis in cervical cancer, has not been elucidated. Here, we show that Srx expression gradually increases during the progression of human cervical cancer and its expression level is closely correlated with lymph node metastasis. Our study also reveals a significant positive correlation between the expression of Srx and β-catenin in cervical cancer tissues. Loss-of-function studies demonstrate that Srx knockdown using a lentiviral vector-mediated specific shRNA decreases the migration and invasion capacity in HeLa (human papilloma virus 18 type cervical cancer cell line) and SiHa SiHa (cervical squamous cancer cell line). Notably, the exact opposite effects were observed in gain-of-function experiments in C-33A cells. Mechanistically, downregulation or upregulation of Srx leads to an altered expression of proteins associated with the Wnt/β-catenin signaling pathway. Furthermore, blockage of the Wnt/β-catenin signaling pathway contributed to attenuated Srx expression and resulted in significant inhibition of cell migration and invasion in cervical cancer cell lines. Combined, Srx might be an oncoprotein in cervical cancer, playing critical roles in activating the Wnt/β-catenin signaling pathway; it may therefore be a therapeutic target for cervical cancer.

Susceptibility of Human Oral Squamous Cell Carcinoma (OSCC) H103 and H376 cell lines to Retroviral OSKM mediated reprogramming

Although numbers of cancer cell lines have been shown to be successfully reprogrammed into induced pluripotent stem cells (iPSCs), reprogramming Oral Squamous Cell Carcinoma (OSCC) to pluripotency in relation to its cancer cell type and the expression pattern of pluripotent genes under later passage remain unexplored. In our study, we reprogrammed and characterised H103 and H376 oral squamous carcinoma cells using retroviral OSKM mediated method. Reprogrammed cells were characterized for their embryonic stem cells (ESCs) like morphology, pluripotent gene expression via quantitative real-time polymerase chain reaction (RT-qPCR), immunofluorescence staining, embryoid bodies (EB) formation and directed differentiation capacity. Reprogrammed H103 (Rep-H103) exhibited similar ESCs morphologies with flatten cells and clear borders on feeder layer. Reprogrammed H376 (Rep-H376) did not show ESCs morphologies but grow with a disorganized morphology. Critical pluripotency genes Oct4, Sox2 and Nanog were expressed higher in Rep-H103 against the parental counterpart from passage 5 to passage 10. As for Rep-H376, Nanog expression against its parental counterpart showed a significant decrease at passage 5 and although increased in passage 10, the level of expression was similar to the parental cells. Rep-H103 exhibited pluripotent signals (Oct4, Sox2, Nanog and Tra-1-60) and could form EB with the presence of three germ layers markers. Rep-H103 displayed differentiation capacity into adipocytes and osteocytes. The OSCC cell line H103 which was able to be reprogrammed into an iPSC like state showed high expression of Oct4, Sox2 and Nanog at late passage and may provide a potential iPSC model to study multi-stage oncogenesis in OSCC.

MiRNA-200c enhances radiosensitivity of esophageal cancer by cell cycle arrest and targeting P21

Esophageal squamous cancer is one of the most fatal malignancies and often suffer recurrence after radiotherapy. Downregulation of miRNA-200c is associated with radiotolerance. We aim to investigate the role of miRNA-200c in radiosensitivity and develop a systemic treatment strategy for esophageal squamous cancer. Overexpression of miRNA-200c by transfection was determined by RT-PCR. Radiosensitizing effect of miRNA-200c on esophageal squamous cancer cells was determined by clonogenic assay and xenograft model. Cell cycle was analyzed by flow cytometry. The levels of Cyclin B1, cyclin D1, cyclin E1, CDK2, CDK4, Cdc2 and P21 protein expressions were detected by western blotting. The results of our study revealed that miRNA-200c enhanced the radiosensitivity significantly in esophageal squamous cancer cell line in vitro and in vivo. miRNA-200c induced G2/M and sub-G1 phase arrest and reduced S phase rate of the irradiated Eca-109 cells and downregulated expression levels of Cyclin B1, cdc2 and upregulated P21 expression level. Present results demonstrate that downregulation of miRNA-200c is associated with radiotolerance. miRNA-200c increases radiosensitivity by G2/M and sub-G1 phase arrest through modulating Cyclin B1, cdc2 and P21 expression levels.

Synergistic Cytotoxicity of β-Elemene and Cisplatin in Gingival Squamous Cell Carcinoma by Inhibition of STAT3 Signaling Pathway.

BackgroundCisplatin remains one of the most active agents and is the mainstay of combination chemotherapy regimens against gingival squamous cell carcinoma. However, the efficacy of cisplatin is limited by its high toxicity and the development of drug resistance. β-elemene, isolated from the Chinese herb Rhizoma zedoariahas, is highly effective against malignancies and has low toxicity, but the development of β-elemene sensitizing chemotherapy in targeting the STAT3 signaling pathway remains unexplored in gingival squamous cell carcinoma. The present study was conducted to assess the chemosensitizing effects of β-elemene for enhancing the cytotoxicity of cisplatin in gingival squamous cell carcinoma.Material/MethodsThe gingival squamous cell carcinoma YD-38 cell line was used. MTT assay, clonogenic assay, annexin V/PI apoptosis assay, Western blot analysis, and xenograft model treatment were carried out in vitro and in vivo.Resultsβ-elemene significantly enhanced proliferative inhibition and cisplatin induced apoptosis in gingival squamous cell carcinoma. Cisplatin combined with β-elemene decreased the expressions of p-STAT3, p-JAK2, and Bcl-2, and increased the expressions of Bax and caspase-3 significantly compared to cisplatin only treatment, as well as in the xenograft model.ConclusionsThe results indicated that β-elemene promoted the anti-proliferative and apoptotic effect of cisplatin by inhibiting STAT3 and blocking the JAK2-STAT3 signaling pathway in GSCC in vitro and in vivo.

Upregulation of maspin expression in human cervical carcinoma cells by transforming growth factor β1 through the convergence of Smad and non-Smad signaling pathways.

Mammary serine protease inhibitor (maspin), encoded by the serpin family B member 5 gene, serves as a tumor suppressor through the inhibition of cancer cell invasion and metastasis. Paradoxically, maspin levels are upregulated in a number of types of malignant cells. Therefore, the regulation of maspin expression may depend on the genetic or epigenetic background and the specific microenvironment of carcinoma cells. In the present study, it was demonstrated that transforming growth factor β1 (TGF-β1) induced maspin expression at the transcript and protein levels in the human cervical carcinoma HeLa and human oral squamous carcinoma HSC4 cell lines. The inhibition of the mothers against decapentaplegic homolog (Smad)-dependent pathway by a Smad3-specific inhibitor suppressed maspin induction by TGF-β1 in HeLa cells. Inhibition of the non-Smad pathway by pretreatment with the mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor U0126, or the p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB202190, attenuated the effect of TGF-β1 on maspin upregulation, whereas pretreatment with pyrrolidine dithiocarbamate (a nuclear factor κB inhibitor), wortmannin (a phosphoinositide 3-kinase inhibitor) or SP600125 (a c-Jun N-terminal kinase inhibitor) did not. Notably, none of these inhibitors eliminated the TGF-β1-induced phosphorylation of Smad2. In addition, mutations at p53-binding sites in the maspin promoter suppressed TGF-β1-induced maspin expression, indicating the necessity of intact p53-binding sites on the maspin promoter. In summary, the induction of maspin expression in HeLa cells requires the convergence of TGF-β1-induced Smad and non-Smad signaling pathways, in which the latter acts via the intermediate signaling molecules MEK1/2 and p38 MAPK.

Lipoteichoic acids from Staphylococcus aureus stimulate proliferation of human non-small-cell lung cancer cells in vitro

Pulmonary infections are frequent complications in lung cancer and may worsen its outcome and survival. Inflammatory mediators are suspected to promote tumor growth in non-small-cell lung cancer (NSCLC). Hence, bacterial pathogens may affect lung cancer growth by activation of inflammatory signalling. Against this background, we investigated the effect of purified lipoteichoic acids (LTA) of Staphylococcus aureus (S. aureus) on cellular proliferation and liberation of interleukin (IL)-8 in the NSCLC cell lines A549 and H226. A549 as well as H226 cells constitutively expressed TLR-2 mRNA. Even in low concentrations, LTA induced a prominent increase in cellular proliferation of A549 cells as quantified by automatic cell counting. In parallel, metabolic activity of A549 cells was enhanced. The increase in proliferation was accompanied by an increase in IL-8 mRNA expression and a dose- and time-dependent release of IL-8. Cellular proliferation as well as the release of IL-8 was dependent on specific ligation of TLR-2. Interestingly, targeting IL-8 by neutralizing antibodies completely abolished the LTA-induced proliferation of A549 cells. The pro-proliferative effect of LTA could also be reproduced in the squamous NSCLC cell line H226. In summary, LTA of S. aureus induced proliferation of NSCLC cell lines of adeno- and squamous cell carcinoma origin. Ligation of TLR-2 followed by auto- or paracrine signalling by endogenously synthesized IL-8 is centrally involved in LTA-induced tumor cell proliferation. Therefore, pulmonary infections may exert a direct pro-proliferative effect on lung cancer growth.

Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 17. Photosensitizing properties and cellular effects of ZnII octacationic and ZnII/PtII hexacationic macrocycles in aqueous media: Perspectives of multimodal anticancer potentialities

The photosensitizing activity of two multiply charged porphyrazine derivatives, i.e. the ZnII species [(CH3)8LZn]8+ and the ZnII/PtII heterobimetallic complex [(PtCl2)(CH3)6LZn]6+ (neutralized byI- ions; L=tetrakis-2,3-[5,6-di(2-pyridyl)pyrazino]porphyrazinato dianion) has been examined in the water medium in the presence of SDS under experimental conditions in which the two species are present exclusively in their monomeric form. The determined quantum yield values (ΦΔ) for both complexes, of interest in photodynamic therapy (PDT), are 2.3–2.5 higher than that of the aluminium compound PcAlSmix (Photosens®) used as the reference standard, an encouraging result for the application of the two cationic species as anticancer curative drugs in PDT. Investigation was also extended to explore the cellular effects on the melanoma C8161 and the oral squamous carcinoma CA-1 cell lines like viability, cellular uptake, cell death modality and cell cycle distribution experiments. The IC50 values for the ZnII and ZnII/PtII cations are consistently lower than those of the reference standard, thus the degree of efficiency as anticancer agents being in the order octacation≫hexacation>PcAlSmix. A large prevalence of apoptosis with respect to necrosis is observed for both charged complexes. Thus, all achieved information from photoactivity and in vitro tests in water solution further enhance perspectives for the application of the two ZnII cation [(CH3)8LZn]8+ and the related ZnII/PtII analog [(PtCl2)(CH3)6LZn]6+ as potential bi-multimodal anticancer drugs.

Different functions of DEPTOR in modulating sensitivity to chemotherapy for esophageal squamous cell carcinoma

There have been paradoxical findings regarding the expression of DEP domain-containing mTOR-interacting protein (DEPTOR) and its role in predicting prognosis in esophageal squamous cell carcinoma (ESCC). Here we show that DEPTOR expression was significantly increased in tumor tissues and predicted good survival in early stage ESCC patients but not in advanced stage patients. In vitro，our studies showed that ESCC cell lines could be classified into relatively high and low DEPTOR-expressing subgroups according to esophageal squamous epithelial cell line Het-1A.In our study, different levels of DEPTOR expression absolutely determined the response to chemotherapy. In relatively low-expressing cell lines, DEPTOR increased chemotherapy sensitivity via deactivation of the AKT pathway. In relatively high-expressing cell lines, DEPTOR increased cell survival and chemoresistance by strong feedback activation of the IRS1-PI3K-AKT-survivin pathway that occurred after downregulation of ribosomal protein S6 kinase (S6K). Collectively, our findings highlight the dichotomous nature of DEPTOR functions in modulating chemotherapy sensitivity in different ESCC cells.

Comparative Effects of Non-Thermal Atmospheric Pressure Plasma on Migration and Invasion in Oral Squamous Cell Cancer, by Gas Type

PurposeThe fourth state of matter, plasma is known as an ionized gas with electrons, radicals and ions. The use of non-thermal plasma (NTP) in cancer research became possible because of the progresses in plasma medicine. Previous studies on the potential NTP-mediated cancer therapy have mainly concentrated on cancer cell apoptosis. In the present study, we compared the inhibitory effect of NTP on cell migration and invasion in the oral squamous cancer cell lines.Materials and MethodsWe used oral squamous cancer cell lines (SCC1483, MSKQLL1) and different gases (N2, He, and Ar). To investigate the mechanism of plasma treatment, using different gases (N2, He, and Ar) which induces anti-migration and anti-invasion properties, we performed wound healing assay, invasion assay and gelatin zymography.ResultsThe results showed that NTP inhibits cancer cell migration and invasion of oral squamous cancer cell. In addition, focal adhesion kinase expression and matrix metalloproteinase-2/9 activity were also inhibited.ConclusionThe suppression of cancer cell invasion by NTP varied depending on the type of gas. Comparison of the three gases revealed that N2 NTP inhibited cell migration and invasion most potently via decreased expression of focal adhesion kinase and matrix metalloproteinase activity.

Twist1 Enhances Hypoxia Induced Radioresistance in Cervical Cancer Cells by Promoting Nuclear EGFR Localization.

Twist1 is a crucial transcription factor that regulates epithelial mesenchymal transition and involves in metastasis. Recent evidence suggests that Twist1 plays important role in hypoxia-induced radioresistance, but the underlying mechanism remains elusive. Here we investigated the change of Twist1 expression in human cervical squamous cancer cell line SiHa after hypoxia treatment. We also explored the role of Twist1 in radioresistance by manipulating the expression level of Twist1. We observed that hypoxia treatment elevated the expression of Twist1 in SiHa cells. Knockdown of Twist1 with siRNA increased the radiosensitivity of SiHa cells under hypoxia condition, accompanied by reduced levels of nuclear Epidermal Growth Factor Receptor (EGFR) and DNA-dependent protein kinase (DNA-PK). Conversely, overexpression of Twist1 led to increased radioresistance of SiHa cells, which in turn increased nuclear EGFR localization and expression levels of nuclear DNA-PK. Moreover, concomitant high expression of hypoxia-inducible factor-1α (HIF-1α) and Twist1 in primary tumors of cervical cancer patients correlated with the worse prognosis after irradiation treatment. Taken together, these data provide new insights into molecular mechanism underlying hypoxia-induced radioresistance in cervical cancer cells, and suggest that Twist1 is a promising molecular target to improve the efficacy of cancer radiotherapy.

In vitro Antiproliferative Effect of Earthworm Coelomic Fluid of Eudrilus Eugeniae, Eisenia Foetida, and Perionyx Excavatus on Squamous Cell Carcinoma-9 Cell Line: A Pilot Study.

Introduction:The earthworm coelomic fluid (ECF) has shown proven antiproliferative effect against breast, liver, gastrointestinal, and brain cancer, but it is least explored in oral cancer. The present in vitro study is an attempt to investigate the antiproliferative activity of ECF on oral cancer cell line squamous cell carcinoma (SCC)-9.Materials and Methods:ECF was collected from the species Eudrilus eugeniae (EE), Eisenia foetida (EF), and Perionyx excavatus (PE) stored at −80°C. Percentage inhibition of ECF on squamous cell carcinoma-9 cells in vitro was recorded at 24 h. Protein estimation was done using Bradford protein assay validated by the biuret method. Cytotoxicity was tested at 2.5, 5, 10, 20, 40, and 80 μg/ml concentrations by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay in SCC-9 cells in vitro. GraphPad Prism 7.0 software was used to calculate the inhibitory concentration (IC50). Chi-square test was used to analyze the difference between samples.Results:The test samples EE, EF, and PE inhibited the growth of SCC-9 cells significantly in a dose-dependent manner, and the IC50 values were found to be 4.6, 44.69, and 5.27 μg/ml, respectively. The antiproliferative effect was found to be variable among the three earthworm species with EE showing the most promising effect followed by PE and EF.Conclusion:Establishing the antiproliferative effect of ECF on oral cancer cells could be an initial step toward drug development and future anticancer research. The preliminary investigation has shown that ECF has a promising antiproliferative effect on oral cancer cells in vitro.SUMMARYThe present pilot study evaluated the in vitro antiproliferative effect of earthworm coelomic fluid (ECF) of Eudrilus eugeniae (EE), Eisenia foetida (EF), and Perionyx excavatus (PE) on squamous cell carcinoma-9 cell line. The ECF inhibitory activity was promising at inhibitory concentration values of 4.6, 44.69, and 5.27 μg/ml, respectively. Further studies pertaining to antiproliferative mechanism of EE, EF, and PE have been planned.Abbreviations Used: ECF: Earthworm coelomic fluid, EE: Eudrilus eugeniae, EF: Eisenia foetida, PE: Perionyx excavatus, MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, SCC: Squamous cell carcinoma, BSA: Bovine serum albumin, PBS: Phosphored buffered saline, ATCC: American Type Culture Collection

P2.01-012 Acquired Chemotherapy Resistance in vitro: miRNA Profiles of Chemotherapy Resistant Squamous Lung Cancer Cell Lines

P2.01-012 Acquired Chemotherapy Resistance in vitro: miRNA Profiles of Chemotherapy Resistant Squamous Lung Cancer Cell Lines

Macrolide Antibiotics Exhibit Cytotoxic Effect under Amino Acid-Depleted Culture Condition by Blocking Autophagy Flux in Head and Neck Squamous Cell Carcinoma Cell Lines.

Autophagy, a self-digestive system for cytoplasmic components, is required to maintain the amino acid pool for cellular homeostasis. We previously reported that the macrolide antibiotics azithromycin (AZM) and clarithromycin (CAM) have an inhibitory effect on autophagy flux, and they potently enhance the cytocidal effect of various anticancer reagents in vitro. This suggests that macrolide antibiotics can be used as an adjuvant for cancer chemotherapy. Since cancer cells require a larger metabolic demand than normal cells because of their exuberant growth, upregulated autophagy in tumor cells has now become the target for cancer therapy. In the present study, we examined whether macrolides exhibit cytotoxic effect under an amino acid-starving condition in head and neck squamous cancer cell lines such as CAL 27 and Detroit 562 as models of solid tumors with an upregulated autophagy in the central region owing to hypovascularity. AZM and CAM induced cell death under the amino acid-depleted (AAD) culture condition in these cell lines along with CHOP upregulation, although they showed no cytotoxicity under the complete culture medium. CHOP knockdown by siRNA in the CAL 27 cells significantly suppressed macrolide-induced cell death under the AAD culture condition. CHOP-/- murine embryonic fibroblast (MEF) cell lines also attenuated AZM-induced cell death compared with CHOP+/+ MEF cell lines. Using a tet-off atg5 MEF cell line, knockout of atg5, an essential gene for autophagy, also induced cell death and CHOP in the AAD culture medium but not in the complete culture medium. This suggest that macrolide-induced cell death via CHOP induction is dependent on autophagy inhibition. The cytotoxicity of macrolide with CHOP induction was completely cancelled by the addition of amino acids in the culture medium, indicating that the cytotoxicity is due to the insufficient amino acid pool. These data suggest the possibility of using macrolides for “tumor-starving therapy”.

Development of Highly Selective Fluorescent Probe Enabling Flow-Cytometric Isolation of ALDH3A1-Positive Viable Cells.

Aldehyde dehydrogenase (ALDH) is overexpressed in some subpopulations of stem cells and cancer cells. We have designed and synthesized the first selective fluorescent probe for class 3 ALDH (ALDH3A1). This probe enabled the visualization of ALDH3A1-positive cells by fluorescence microscopy as well as flow-cytometric isolation of ALDH3A1-positive viable cells from a human Caucasian esophageal squamous cell line (OE21) that heterogeneously expresses ALDH3A1.

Cantharidin Induced Oral Squamous Cell Carcinoma Cell Apoptosis via the JNK-Regulated Mitochondria and Endoplasmic Reticulum Stress-Related Signaling Pathways.

Oral cancer is a subtype of head and neck cancer which represents 2.65% of all human malignancies. Most of oral cancer is histopathologically diagnosed as oral squamous cell carcinoma (OSCC). OSCC is characterized by a high degree of local invasion and a high rate of metastasis to the cervical lymph nodes. How to prevention and treatment of OSCC is important and imperative. Here, we investigated the therapeutic effect and molecular mechanism of cantharidin, an active compound isolated from blister beetles, on OSCC in vitro. Results showed that cantharidin significantly decreased cell viability in human tongue squamous carcinoma-derived SAS, CAL-27, and SCC-4 cell lines. The further mechanistic studies were carried out in SAS cells. Cantharidin also significantly increased apoptosis-related signals, including caspase-9, caspase-7 and caspase-3 proteins. Besides, cantharidin decreased mitochondrial transmembrane potential (MMP) and induced cytochrome c and apoptosis inducing factor (AIF) release. Cantharidin also increased Bax, Bid, and Bak protein expressions and decreased Bcl-2 protein expression. Cantharidin could also increase the endoplasmic reticulum (ER) stress signals, including the expressions of phosphorylated eIF-2α and CHOP, but not Grp78 and Grp94. Furthermore, cantharidin reduced pro-caspase-12 protein expression. In signals of mitogen-activated protein kinases, cantharidin increased the phosphorylation of JNK, but not ERK and p38. Transfection of shRNA-JNK to OSCC cells effectively reversed the cantharidin-induced cell apoptotic signals, including the mitochondrial and ER stress-related signaling molecules. Taken together, these findings suggest that cantharidin induces apoptosis in OSCC cells via the JNK-regulated mitochondria and ER stress-related signaling pathways.