The amide derivative of anticopalic acid induces non-apoptotic cell death in triple-negative breast cancer cells by inhibiting FAK activation.

Anticopalic acid (ACP), a labdane type diterpenoid obtained from Kaempferia elegans rhizomes, together with 21 semi-synthetic derivatives, were evaluated for their cancer cytotoxic activity. Most derivatives displayed higher cytotoxic activity than the parent compound ACP in a panel of nine cancer cell lines. Among the tested compounds, the amide 4p showed the highest cytotoxic activity toward leukemia cell lines, HL-60 and MOLT-3, with IC50 values of 6.81 ± 1.99 and 3.72 ± 0.26 µM, respectively. More interestingly, the amide derivative 4l exhibited cytotoxic activity with an IC50 of 13.73 ± 0.04 µM against the MDA-MB-231 triple-negative breast cancer cell line, which is the most aggressive type of breast cancer. Mechanistic studies revealed that 4l induced cell death in MDA-MB-231 cells through non-apoptotic regulated cell death. In addition, western blot analysis showed that compound 4l decreased the phosphorylation of FAK protein in a concentration-dependent manner. Molecular docking simulations elucidated that compound 4l could potentially inhibit FAK activation by binding to a pocket of FAK kinase domain. The data suggested that compound 4l could be a potential FAK inhibitor for treating triple-negative breast cancer and worth being further investigated.

p­STAT3 influences doxorubicin and etoposide resistance of A549 cells grown in an in vitro 3D culture model.

Tumor microenvironment undoubtedly has a significant impact on therapeutic responses. Abundant evidence suggests that the 3D in vitro culture holds great promise for drug discovery and development by bridging the gap between conventional 2D culture and animal models. The present study described 3D basement membrane culture of A549 cells, which mimics the complex 3D arrangement of tumors in vivo and elucidates the underlying mechanisms of microenvironmental influences on cellular functions and therapeutic efficacy. A549 cells cultured in 3D undergo G0/G1 phase arrest and decreased migratory and invasive capacity, indicating dormant cell characteristics. Hypoxia, apoptosis and stemness were demonstrated in the A549 cells in 3D architecture compared with the 2D­cultured counterparts. More importantly, cells in the 3D environment exhibited increased resistance to different classes of anticancer agents. Western blotting revealed changes in the levels of key cancer­associated pathways, phosphorylated (p)­STAT3, p­ERK, and p­Akt, in response to 3D culture compared with 2D monolayer culture. Notably, mechanistic analysis using specific inhibitors showed that the STAT3 inhibitor overcomes the 3D culture­induced doxorubicin and etoposide resistance. These results implicated an important role of p­STAT3 in conferring chemoresistance in 3D­cultured A549 cells, as well as the use of STAT3 inhibitor as a potential chemosensitizer to improve drug sensitivity. Thus, 3D culture systems, that more closely resemble in vivo tumor biology, may be more effective models in searching for novel chemotherapeutic agents and therapeutic targets for cancer treatment.

Acetogenins from the stems of Uvaria micrantha showing antiproliferative effects on HepG2 liver cancer cells.

Five mono-tetrahydrofuran acetogenins: uvamicranins A-E and three known mono-tetrahydrofuran acetogenins; reticulatacin, calamistrin A, and uvarigrin, were isolated from the stems of Uvaria micrantha (Annonaceae). Their structures were elucidated by 2D NMR and high-resolution mass spectral analysis. The absolute configurations of uvamicranins A and B were determined by modified Mosher's method. Evaluation of antiproliferative activity of the isolated compounds showed that they were more potent towards the human hepatocellular carcinoma cell line HepG2, compared to the five other tested cell lines. Among the tested compounds, uvamicranin B (UvB) and uvarigrin (Uv) possessed strong antiproliferative activity with IC50 values of 2.89 ± 0.71 µM and 0.37 ± 0.06 µM, respectively. The antiproliferative mechanism of UvB and Uv, was investigated in HepG2 cell line showing that both compounds marginally induced apoptotic cell death, but exhibited cytostatic effect through induction of cell cycle arrest at the G2/M phase.

JAK2/STAT3­mediated dose­dependent cytostatic and cytotoxic effects of sesquiterpene lactones from Gymnanthemum extensum on A549 human lung carcinoma cells.

Due to drug resistance and disease recurrence, lung cancer remains one of the primary cancer­related causes of death in both men and women worldwide. In addition, lung cancer is clinically silent and thus most patients are at an advanced stage at the time of diagnosis. The limited efficiency of current conventional chemotherapies necessitates the search for novel effective anticancer agents. The present study demonstrated the anti­proliferative effect and apoptosis­inducing activity of three sesquiterpene lactones isolated from Gymnanthemum extensum, vernodalin (VDa), vernolepin (VLe) and vernolide (VLi), on A549 human lung cancer cells. Treatment with sub­cytotoxic doses (cell viability remaining >75%) of VDa, VLe and VLi, arrested progression of the A549 cell cycle at the G0/G1 phase, while cytotoxic doses of the three compounds induced G2/M phase arrest and apoptosis. Mechanistic studies revealed that VDa, VLe and VLi may exert their anti­tumor activity through the JAK2/STAT3 pathway. Molecular docking analysis confirmed that VDa, VLe and VLi formed hydrogen bonds with the FERM domain of JAK2 protein. Overall, the present study highlighted the potential therapeutic value of VDa, VLe and VLi to be further developed as anticancer agents for the treatment of lung cancer.

Identification of potential cervical cancer serum biomarkers in Thai patients.

Cervical cancer is one of the most common causes of cancer-associated mortality in females worldwide. Serum biomarkers are important tools for diagnosis, disease staging, monitoring treatment and detecting recurrence in different types of cancer. However, only a small number of established biomarkers have been used for clinical diagnosis of cervical cancer. Therefore, the identification of minimally invasive, sensitive and highly specific biomarkers for detection of cervical cancer may improve outcomes. In the present pilot study, changes in disease-relevant proteins in 31 patients with cervical cancer were compared with 16 healthy controls. The Human 14 Multiple Affinity Removal system was used to deplete the 14 most abundant serum proteins to decrease sample complexity and to enrich proteins that exhibited decreased levels of abundance in the serum samples. Immunoaffinity-depleted serum samples were analyzed by in-gel digestion, followed by liquid chromatography mass spectrometry analysis and data processing. Automated quantitative western blot assays and receiver operating characteristic (ROC) curves were used to evaluate the differential protein expression levels between the two groups. Capillary electrophoresis-based western blot analysis was performed to quantitatively determine serum levels of the candidate biomarkers. Significantly increased levels of α-1-antitrypsin (A1AT) and pyrroline-5-carboxylate reductase 2 (PYCR2) were detected, whereas the levels of transthyretin (TTR), apolipoprotein A-I (ApoA-I), vitamin D binding protein (VDBP) and multimerin-1 (MMRN1) were significantly decreased in patients with cervical cancer compared with the healthy controls. ROC curve analysis indicated that the sensitivity and specificity was improved through the combination of the 6 candidate biomarkers. In summary, the results demonstrated that 6 candidate biomarkers (A1AT, PYCR2, TTR, ApoA-I, VDBP and MMRN1) exhibited significantly different expression between serum samples from healthy controls and patients with cervical cancer. These proteins may represent potential biomarkers for distinguishing patients with cervical cancer from healthy controls and for differentiation of patient subgroups.

Vernodalidimer L, a sesquiterpene lactone dimer from Vernonia extensa and anti-tumor effects of vernodalin, vernolepin, and vernolide on HepG2 liver cancer cells.

Vernonia extensa, known as "Phim Phai Lin" in Thai, is distributed in most regions of Thailand. The plant has been used in Ayurveda and traditionally used to treat malaria and cancer, and possesses several sesquiterpene lactones. This study aimed to investigate and identify the active constituents by bioactivity-based analysis, as well as to evaluate the cytotoxic activity of V. extensa by MTT or XTT assays in ten cancer cell lines (Liver HepG2 and S102; Bile duct HuCCA-1; Leukemia HL-60 and MOLT-3; Lung A549 and H69AR; Breast MDA-MB-231 and T47D; Cervical HeLa). Bioactivity-guided fractionation and semi-preparative HPLC purification were used to separate the bioactive constituents. Apoptosis-inducing activity and cell cycle inhibitory effect of selected active compounds were determined on HepG2 cells by flow cytometric analysis. Bioactivity-guided fractionation of the CH2Cl2 extract and chemical investigation of the cytotoxic fractions led to the isolation of a new sesquiterpenoid pseudo-dimer named vernodalidimer L, together with eight known sesquiterpenoids from the aerial part of V. extensa. The structures of the isolates were elucidated based on spectroscopic analysis, including 1D and 2D NMR and HRMS. Vernolide has potent broad-spectrum cytotoxicity with IC50 values in the range of 0.91-13.84 µM, against all ten cancer cell lines. The annexin-V flow cytometric analysis showed that vernodalin, vernolepin, and vernolide induced apoptosis on HepG2 cells in a dose dependent manner and these effects correlated with G2/M phase cell cycle arrest. Our results indicated that vernodalin, vernolepin, and vernolide have potential to be used as lead compounds in the development of a therapeutic natural product for treatment of liver cancer.

Urinary biomarkers for the diagnosis of cervical cancer by quantitative label-free mass spectrometry analysis.

Due to the invasive procedure associated with Pap smears for diagnosing cervical cancer and the conservative culture of developing countries, identifying less invasive biomarkers is of great interest. Quantitative label-free mass spectrometry was performed to identify potential biomarkers in the urine samples of patients with cervical cancer. This technique was used to study the differential expression of urinary proteomes between normal individuals and cancer patients. The alterations in the levels of urinary proteomes in normal and cancer patients were analyzed by Progenesis label-free software and the results revealed that 60 proteins were upregulated while 73 proteins were downregulated in patients with cervical cancer. This method could enrich high molecular weight proteins from 100 kDa. The protein-protein interactions were obtained by Search Tool for the Retrieval of Interacting Genes/Proteins analysis and predicted the biological pathways involving various functions including cell-cell adhesion, blood coagulation, metabolic processes, stress response and the regulation of morphogenesis. Two notable upregulated urinary proteins were leucine-rich α-2-glycoprotein (LRG1) and isoform-1 of multimerin-1 (MMRN1), while the 3 notable downregulated proteins were S100 calcium-binding protein A8 (S100A8), serpin B3 (SERPINB3) and cluster of differentiation-44 antigen (CD44). The validation of these 5 proteins was performed by western blot analysis and the biomarker sensitivity of these proteins was analyzed individually and in combination with receiver operator characteristic curve (ROC) analysis. Quantitative mass spectrometry analysis may allow for the identification of urinary proteins of high molecular weight. The proteins MMRN1 and LRG1 were presented, for the first time, to be highly expressed urinary proteins in cervical cancer. ROC analysis revealed that LRG1 and SERPINB3 could be individually used, and these 5 proteins could also be combined, to detect the occurrence of cervical cancer.

Mechanism of ECM-induced dormancy and chemoresistance in A549 human lung carcinoma cells.

It is now widely accepted that the tumor microenvironment influences the fate of cancer cells and plays crucial roles in regulating tumor dormancy and chemoresistance. The standard cell culture system on plastic surfaces does not account for cell interactions with the extracellular matrix (ECM), and is thus a less reliable approach to analyze cellular activity ex vivo. In the present study, A549 lung cancer cells were cultured in a semi-solid growth substrate (Matrigel) to mimic the tumor microenvironment and to investigate the role played by ECM proteins, as well as to evaluate the mechanism of cell-ECM communication. A549 cells embedded in semi-solid Matrigel exhibited dormant cell characteristics, including decreased cell proliferation, migration and invasion rates, compared with the corresponding cells cultured on plastic plates. Exposure of A549 cells to Matrigel leads to resistance against conventional chemotherapeutic drugs (etoposide, paclitaxel, vinblastine, doxorubicin and 2-deoxy-D-glucose). Cell cycle distribution analysis indicated that a larger percentage of the cells embedded within semi-solid Matrigel was arrested in the G0/G1 phase. RT-qPCR analysis revealed that A549 cells cultured in semi-solid Matrigel exhibited a marked decrease in the expression levels of genes that are related to tumor progression and invasion (uPA, uPAR, MMP2, MMP7, MMP9 and CXCR4). The effects of altering various signaling pathways, such as p-ERK, p-Akt and p-STAT3, were evaluated, in order to assess whether these pathways could account for the observed responses of the cells. The inhibition of ERK1/2 and Akt activation using specific inhibitors induced G0/G1 arrest and drug resistance. These results demonstrated that Matrigel drove A549 cells into a drug-resistant dormancy state, most likely through inhibition of the ERK1/2 and PI3K/Akt pathways. Cell culture within semi-solid Matrigel offered a simple in vitro model for studying the mechanisms responsible for tumor dormancy and drug resistance. These studies may lead to therapeutic approaches that can eliminate dormant tumor cells and prevent disease recurrence.

Apigenin inhibits growth and induces apoptosis in human cholangiocarcinoma cells.

A promising nutraceutical, apigenin, was recently revealed to exhibit biological activity in inhibiting several types of cancer. The effects of apigenin on the growth inhibition and apoptosis of the cholangiocarcinoma HuCCA-1 cell line were investigated. Protein alterations subsequent to apigenin treatment were studied using a proteomic approach. The values of 20, 50 and 90% inhibition of cell growth (IC20, IC50 and IC90) were determined by MTT cell viability assay. Apoptotic cell death was detected using two different methods, a flow cytometric analysis (Muse Cell Analyzer) and DNA fragmentation assay. A number of conditions including attached and detached cells were selected to perform two-dimensional gel electrophoresis (2-DE) to study the alterations in the expression levels of treated and untreated proteins and identified by liquid chromatography (LC)/tandem mass spectrometry (MS/MS). The IC20, IC50 and IC90 values of apigenin after 48 h treatment in HuCCA-1 cells were 25, 75 and 200 µM, respectively, indicating the cytotoxicity of this compound. Apigenin induced cell death in HuCCA-1 cells via apoptosis as detected by flow cytometric analysis and exhibited, as confirmed with DNA fragmentation, characteristics of apoptotic cells. A total of 67 proteins with altered expression were identified from the 2-DE analysis and LC/MS/MS. The cleavage of proteins involved in cytoskeletal, cytokeratin 8, 18 and 19, and high expression of S100-A6 and S100-A11 suggested that apoptosis was induced by apigenin via the caspase-dependent pathway. Notably, two proteins, heterogeneous nuclear ribonucleoprotein H and A2/B1, disappeared completely subsequent to treatment, suggesting the role of apigenin in inducing cell death. The present study indicated that apigenin demonstrates an induction of growth inhibition and apoptosis in cholangiocarcinoma cells and the apoptosis pathway was confirmed by proteomic analysis.

Curcumin suppresses vasculogenic mimicry capacity of hepatocellular carcinoma cells through STAT3 and PI3K/AKT inhibition.

BACKGROUND: Vasculogenic mimicry (VM) refers to the process in which highly invasive cancer cells mimic endothelial cells by forming blood channels. In the present study, we investigated the effect of curcumin, a natural product from turmeric, on VM of SK-Hep-1 human hepatocellular carcinoma (HCC) cells. MATERIALS AND METHODS: In vitro VM, cell migration, and matrix metalloproteinase-9 (MMP9) production of HCC cells were determined by Matrigel tube formation assay, Transwell cell migration assay, and gelatin zymography, respectively. Effects of curcumin on AKT, signal transducer and activator of transcription 3 (STAT3), extracellular signal-regulated kinase (ERK) and nuclear factor-κB (NF-κB) signaling pathways were determined by immunoblot analysis. RESULTS: At non-cytotoxic concentrations, curcumin inhibited VM, reduced cell migration and MMP9 production of the HCC cells. Further study revealed that the anti-VM effect of curcumin was due to inhibition of AKT and STAT3 phosphorylation, as confirmed by specific inhibitors. CONCLUSION: Curcumin presents proven potential as an anti-VM agent in HCC cells, through down-regulation of STAT3 and AKT signaling pathways.

Role of mTOR inhibitor in cholangiocarcinoma cell progression.

Cholangiocarcinoma (CCA) is a lethal malignancy of the biliary epithelium. CCA is resistant to currently available chemotherapy; therefore, new drugs as well as new molecular targets must be identified for the development of an effective treatment for CCA. The present study showed that RAD001 (everolimus), a derivative of rapamycin and an orally bioavailable mammalian target of rapamycin (mTOR) inhibitor, exhibits cytotoxic and antimetastatic effects in a CCA cell line, RMCCA-1. Treatment with low concentrations of RAD001 resulted in a significant reduction of in vitro invasion and migration of RMCCA-1, concomitant with a reduction of filopodia and alteration of the actin cytoskeleton. Although, matrix metalloproteinase-9 and -14 activities were unaltered. However, at high concentrations, RAD001 exhibited cytotoxic effects, reducing cell proliferation and inducing apoptotic cell death. Overall, RAD001 exhibits multiple effects mediated by the inhibition of the mTOR, which may serve as a promising agent for the treatment of CCA.

CD24 induces the invasion of cholangiocarcinoma cells by upregulating CXCR4 and increasing the phosphorylation of ERK1/2.

Cholangiocarcinoma is a malignant biliary tract tumor with an extremely poor prognosis. CD24 expression has been linked to the aggressiveness of cholangiocarcinoma cells and the adverse prognosis of cholangiocarcinoma patients. In the present study, the underlying mechanism of aggressive CD24+ cholangiocarcinoma cell behavior was elucidated. The magnetic-activated cell sorting system was used to isolate CD24+ and CD24- cell populations from RMCCA1 cholangiocarcinoma cells. Using a human tumor metastasis PCR array, it was observed that numerous tumor-associated genes were upregulated in the CD24+ cells, including CXC chemokine receptor type 4 (CXCR4). In addition, an intracellular signaling array demonstrated the activation of extracellular signal-regulated kinase (ERK)1/2, which is downstream of the CXCR4 signaling cascade, in the CD24+ cells. Inhibition of CXCR4 or ERK1/2 significantly inhibited the motility and invasiveness of the CD24+ cells. The present study indicates that CXCR4 and ERK1/2 are induced by CD24 and that these proteins are associated with cholangiocarcinoma cell invasion.

Clinical and molecular findings in Thai patients with isolated methylmalonic acidemia.

Isolated methylmalonic acidemia (MMA) is a genetically heterogeneous organic acid disorder caused by either deficiency of the enzyme methylmalonyl-CoA mutase (MCM), or a defect in the biosynthesis of its cofactor, adenosyl-cobalamin (AdoCbl). Herein, we report and review the genotypes and phenotypes of 14 Thai patients with isolated MMA. Between 1997 and 2011, we identified 6 mut patients, 2 cblA patients, and 6 cblB patients. The mut and cblB patients had relatively severe phenotypes compared to relatively mild phenotypes of the cblA patients. The MUT and MMAB genotypes were also correlated to the severity of the phenotypes. Three mutations in the MUT gene: c.788G>T (p.G263V), c.809_812dupGGGC (p.D272Gfs*2), and c.1426C>T (p.Q476*); one mutation in the MMAA gene: c.292A>G (p.R98G); and three mutations in the MMAB gene: c.682delG (p.A228Pfs*2), c.435delC (p.F145Lfs*69), and c.585-1G>A, have not been previously reported. RT-PCR analysis of a common intron 6 polymorphism (c.520-159C>T) of the MMAB gene revealed that it correlates to deep intronic exonization leading to premature termination of the open reading frame. This could decrease the ATP:cobalamin adenosyltransferase (ATR) activity resulting in abnormal phenotypes if found in a compound heterozygous state with a null mutation. We confirm the genotype-phenotype correlation of isolated MMA in the study population, and identified a new molecular basis of the cblB disorder.

Expression of CD24 in cholangiocarcinoma cells is associated with disease progression and reduced patient survival.

Cholangiocarcinoma is frequently found to invade local tissues and metastasize to distal organs. We investigated the expression of CD24 in cholangiocarcinoma samples and its prognostic significance. In addition, the cellular function of CD24 was studied in the RMCCA1 cholangiocarcinoma cell line. High CD24 expression significantly correlated with lymph node metastasis and positive surgical margins in cholangiocarcinoma patients. Univariate and multivariate analyses further demonstrated that CD24 expression was significantly associated with the overall survival of these patients (p=0.007 and p=0.040, respectively). For in vitro studies, the magnetic-activated cell sorting (MACS) system was used to isolate CD24+ and CD24- cell populations from RMCCA1 cells. CD24+ RMCCA1 cells had increased chemoresistance, adhesion (p=0.004), motility (p<0.001), migration (p<0.001) and invasion (p<0.001) capabilities when compared to CD24- cells. The matrix metalloproteinase (MMP)-7 was significantly elevated in CD24+ RMCCA1 cells (p=0.01). We found that inhibition of CD24 using siRNA silencing significantly decreased the invasive capacity of RMCCA1 cells. Both clinical and in vitro studies suggest that expression of CD24 is associated with cholangiocarcinoma disease progression. CD24 may thus serve as a new target for directed molecular therapy of cholangiocarcinoma.

Novel mutations found in two genes of thai patients with isolated methylmalonic acidemia.

Molecular genetic analysis of three patients diagnosed with isolated methylmalonic acidemia (MMA) revealed that one was mut (0) MMA, with a mutation in the MUT gene encoding the L: -methylmalonyl-CoA mutase (MCM), and two were cblB MMA, with mutations in the MMAB gene required for synthesizing the deoxyadenosylcobalamin cofactor of MCM. The mut (0) patient was homozygous for a novel nonsense mutation in MUT, p.R31X (c.167C --> T), and heterozygous for three previously described polymorphisms, p.K212K (c.712A --> G), p.H532R (c.1671A --> G), and p.V671I (c.2087G --> A). The new MMAB mutation, p.E152X (c.454G --> T), was found to be homozygous in one cblB patient and heterozygous in the other patient, who also had four intron polymorphisms in this gene.

Clinical and molecular characterization of an extended family with Fabry disease.

OBJECTIVE: To characterize clinical manifestations, biochemical changes, mutation of alpha-Galactosidase (alpha-Gal A) gene A (GLA), and functional capability of mutant protein. MATERIAL AND METHOD: Seventeen subjects from a family with a newly diagnosed patient with Fabry disease were enrolled in the present study. In each individual, clinical history, physical examination, leukocyte enzyme activity of alpha-Gal A, and mutation analysis were performed. Those with a mutation were further investigated by ophthalmological and audiological evaluations, electrocardiography, echocardiogram, urinalysis, and blood tests to determine renal insufficiency. Expression study of the mutant protein was performed using a Pichia pastoris expression system. RESULTS: Four affected males and five symptomatic female carriers were identified. Clinical manifestations included severe neuropathic pain, acroparesthesia, hypo-/hyper-hidrosis, frequent syncope, ischemic stroke, cardiac hypertrophy, corneal dystrophy and cart-wheel cataract, high frequency sensorineural hearing loss, periorbital edema and subcutaneous edema over hands and interphalangeal joints. None had angiokeratoma or renal symptoms. The authors identified a novel mutation, p.L106R, in the GLA gene. Recombinant expression of the mutant protein gave little or no enzyme activity compared to the normal protein. CONCLUSION: There were intrafamilial clinical variabilities, but consistent findings of the absence of angiokeratoma and renal symptoms, which could represent a unique feature of this particular mutation.

Proteomic profiling of cholangiocarcinoma cell line treated with pomiferin from Derris malaccensis.

Pomiferin, a prenylated isoflavonoid from Derris malaccensis with strong anti-fungal and anti-oxidant activities, showed cytotoxic activity towards human cholangiocarcinoma cells (HuCCA-1), with IC(50) of 0.9 microg/mL. Pomiferin caused apoptosis, detectable by DNA fragmentation. Two-dimensional PAGE showed increased expression of 12 proteins, namely glucose-regulated protein 75 (grp 75), calcyclin (S100A6), degraded cytokeratin 19, ATP synthase D, ribosomal protein P0, degraded cytokeratin 18 (two spots pI/MW 6.03/29.9 and pI/MW 4.66/21.5), cofilin, annexin A1, triose phosphate isomerase, peroxiredoxin-1, calgizzarin, and profilin. In contrast, cytokeratins (CK) 7, 18 and 19 were down-regulated, and were shown by 1-DE immunodetection to be degraded.

The molecular basis of mucopolysaccharidosis type I in two Thai patients.

Two Thai patients diagnosed with Hurler syndrome (mucopolysaccharidosis type 1, MPS I) were found to have no detectable alpha-iduronidase (E.C. 3.2.1.76) activity in leukocytes, while normal Thai children all had significant activity, with a mean of 135 +/- 30 nmol/mg/18h. One patient was heterozygous for A75T (311G>A) and S633L (1986C>T) mutation, previously reported to cause MPS I, together with 9 other heterozygous polymorphisms also found in normal controls. The other patient had the previously described frameshift mutation 252insert C and a new nonsense mutation E299X (983G>T).

Proteomic analysis of cholangiocarcinoma cell line.

Cholangiocarcinoma (CCA), a malignant tumor derived from bile duct epithelium, occurs with a higher incidence in tropical countries, such as Thailand. Distinguishing CCA from hepatocellular carcinoma (HCC) of the liver often requires the use of histochemistry, so molecular markers for diagnosis and prognosis are still required. In this study, the two-dimensional (2-D) protein map of a Thai human bile duct epithelial carcinoma cell line (HuCCA-1) has been compared to human hepatocellular carcinoma cell lines (HepG2 and HCC-S102) and a human breast epithelial cancer cell line (MCF-7). Our results show that HuCCA-1 expressed a unique pattern of proteins. Forty-three major proteins were identified by matching to the map of MCF-7, and by matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and electrospray ionization-tandem MS (ESI-MS/MS). Cytokeratins CK8 and CK18 were overexpressed in both HuCCA-1 and HCC, while CK7 and CK19 were only expressed in HuCCA-1. Four specific proteins with MW/pI 57.2/5.21 (U1, vimentin), 42.2/6.20 (U2), 43.2/6.20 (U3, EF-TU), and 42.2/6.40 (U4, unidentified) were absent from HepG2. U2 showed high expression in HuCCA-1, while U1 and U4 showed high expression in HCC-S102. U2 could be separated in 2 proteins, U2/1 (alpha-enolase) and U2/2 (not identified) by using IPG pH 4-7. Galectin-3 showed high expression level in HuCCA-1 by 1-DE immunodetection, and gave only one spot with MW 32.9 kDa and pI 8.29 on 2-DE immunoblotting, Thus, certain proteins, namely CK7, CK19, U2/2 and galectin-3, may be good markers useful for differential diagnosis of cholangiocarcinoma compared to hepatocellular carcinoma.