Detection of high-risk HPV 16 genotypes in cervical cancers using isothermal DNA amplification with electrochemical genosensor.

Cervical cancer emerges as the third most prevalent types of malignancy among women on a global scale. Cervical cancer is significantly associated with the persistent infection of human papillomavirus (HPV) type 16. The process of diagnosing is crucial in order to prevent the progression of a condition into a malignant state. The early detection of cervical cancer through initial stage screening is of the utmost significance in both the prevention and effective management of this disease. The present detection methodology is dependent on quantitative polymerase chain reaction (qPCR), which necessitates the use of a costly heat cycler instrument. In this study, we report the development of an electrochemical DNA biosensor integrated with an isothermal recombinase polymerase amplification (RPA) reaction for the detection and identification of the high-risk HPV-16 genotype. The electrochemical biosensor exhibited a high degree of specificity and sensitivity, as evidenced by its limit of detection (LOD) of 0.23 copies/µL of HPV-16 DNA. The validity of this electrochemical platform was confirmed through the analysis of 40 cervical tissues samples, and the findings were consistent with those obtained through polymerase chain reaction (PCR) testing. Our straightforward electrochemical detection technology and quick turnaround time at 75 min make the assay suitable for point-of-care testing in low-resource settings.

Identification of Glucose-6 Phosphate Dehydrogenase Deficient Patients Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy Using Partial Least Squares Discriminant Analysis in Aqueous Blood Samples.

Glucose-6 phosphate dehydrogenase (G6PD) deficiency is an X-linked blood disease that affects 400 million people globally and is especially prevalent in malaria-endemic regions. A significant portion of carriers are asymptomatic and undiagnosed posing complications in the eradication of malaria as it restricts the types of drugs used for malaria treatment. A simple and accurate diagnosis of the deficiency is vital in the eradication of malaria. In this study, we investigate the potential of attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) as a diagnostic technique for G6PD deficiency. Venous blood samples were collected in lithium heparin anticoagulant tubes from G6PD partial and fully deficient volunteers, n = 17, and normal volunteers, n = 59, in Khon Kaen, Thailand. Spectra of aqueous and dry samples were acquired of whole blood, plasma, and red blood cells, and modeled using partial least squares discriminant analysis (PLS-DA). PLS-DA modeling resulted in a sensitivity of 0.800 and specificity of 0.800 correctly classifying fully deficient participants as well as a majority of partially deficient females who are often misdiagnosed as normal by current screening methods. The viability of utilizing aqueous samples has always been hindered by the variability of hydration in the sample, but by employing multicurve curve resolution-alternating least squares to subtract water from each sample we are able to produce high-quality spectra with minimized water contributions. The approach shows proof of principle that ATR FT-IR combined with multivariate data analysis could become a frontline screening tool for G6PD deficiency by improving tailored drug treatments and ultimately saving lives.

A Multianalyte Electrochemical Genosensor for the Detection of High-Risk HPV Genotypes in Oral and Cervical Cancers.

Infection with high-risk human papillomavirus (HPV) is a major risk factor for oral and cervical cancers. Hence, we developed a multianalyte electrochemical DNA biosensor that could be used for both oral and cervical samples to detect the high-risk HPV genotypes 16 and 18. The assay involves the sandwich hybridization of the HPV target to the silica-redox dye reporter probe and capture probe, followed by electrochemical detection. The sensor was found to be highly specific and sensitive, with a detection limit of 22 fM for HPV-16 and 20 fM for HPV-18, between the range of 1 fM and 1 µM. Evaluation with oral and cervical samples showed that the biosensor result was consistent with the nested PCR/gel electrophoresis detection. The biosensor assay could be completed within 90 min. Due to its simplicity, rapidity, and high sensitivity, this biosensor could be used as an alternative method for HPV detection in clinical laboratories as well as for epidemiological studies.

Detection of Human Cholangiocarcinoma Markers in Serum Using Infrared Spectroscopy.

Cholangiocarcinoma (CCA) is a malignancy of the bile duct epithelium. Opisthorchis viverrini infection is a known high-risk factor for CCA and in found, predominantly, in Northeast Thailand. The silent disease development and ineffective diagnosis have led to late-stage detection and reduction in the survival rate. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) is currently being explored as a diagnostic tool in medicine. In this study, we apply ATR-FTIR to discriminate CCA sera from hepatocellular carcinoma (HCC), biliary disease (BD) and healthy donors using a multivariate analysis. Spectral markers differing from healthy ones are observed in the collagen band at 1284, 1339 and 1035 cm-1, the phosphate band (vsPO2-) at 1073 cm-1, the polysaccharides band at 1152 cm-1 and 1747 cm-1 of lipid ester carbonyl. A Principal Component Analysis (PCA) shows discrimination between CCA and healthy sera using the 1400-1000 cm-1 region and the combined 1800-1700 + 1400-1000 cm-1 region. Partial Least Square-Discriminant Analysis (PLS-DA) scores plots in four of five regions investigated, namely, the 1400-1000 cm-1, 1800-1000 cm-1, 3000-2800 + 1800-1000 cm-1 and 1800-1700 + 1400-1000 cm-1 regions, show discrimination between sera from CCA and healthy volunteers. It was not possible to separate CCA from HCC and BD by PCA and PLS-DA. CCA spectral modelling is established using the PLS-DA, Support Vector Machine (SVM), Random Forest (RF) and Neural Network (NN). The best model is the NN, which achieved a sensitivity of 80-100% and a specificity between 83 and 100% for CCA, depending on the spectral window used to model the spectra. This study demonstrates the potential of ATR-FTIR spectroscopy and spectral modelling as an additional tool to discriminate CCA from other conditions.

Monitoring the Progression of Liver Fluke-Induced Cholangiocarcinoma in a Hamster Model Using Synchrotron FTIR Microspectroscopy and Focal Plane Array Infrared Imaging.

Cholangiocarcinoma (CCA) is a bile duct cancer that originates in the bile duct epithelium. Northeastern Thailand has the highest incidence of CCA, and there is a direct correlation with liver fluke (Opisthorchis viverrini) infection. The high mortality rate of CCA is a consequence of delayed diagnosis. Fourier transform infrared (FTIR) spectroscopy is a powerful technique that detects the absorbance of molecular vibrations and is perfectly suited for the interrogation of biological samples. In this study, we applied synchrotron radiation-FTIR (SR-FTIR) microspectroscopy and focal plane array (FPA-FTIR) microspectroscopy to characterize periductal fibrosis and bile duct cells progressing to CCA induced by inoculating O. viverrini metacercariae into hamsters. SR-FTIR and FPA-FTIR measurements were performed in liver sections harvested from 1-, 2-, 3-, and 6-month post-infected hamsters compared to uninfected liver tissues. Principal component analysis (PCA) of the tissue samples showed a clear discrimination among uninfected and early-stage (1 and 2 months) and cancerous-stage (3 and 6 months) tissues. The discrimination is based on intensity changes in the phosphodiester band (1081 cm-1), amino acid residue (∼1396 cm-1), and C═O stretching carboxylic esters (1745 cm-1). Infected tissues also show definitive bands at ∼1280, 1234, and 1201 cm-1 characteristic of the collagen triplet and indicative of fibrosis. Hierarchical cluster analysis (HCA) was performed on the FPA data and showed a classification into specific cell types. Hepatocyte, fibrotic lesion, and bile duct (cancer) were classified and HCA mapping showed similar cellular distribution pattern compared to Sirius red staining. This study was also extended to less invasive sample analysis using attenuated total reflectance-FTIR (ATR-FTIR) spectroscopy. Sera from O. viverrini-infected and uninfected hamsters were analyzed using multivariate analysis, including principal component analysis (PCA), and partial least squares-discriminant analysis (PLS-DA). PCA was able to classify spectra of normal, early-stage CCA, and CCA, while the PLS-DA gave 100% accuracy for the validation. The model was established from 17 samples (11 normal, 6 cancer) in the calibration set and 9 samples in the validation set (4 normal, 2 cancer, 3 precancerous). These results indicate that FTIR-based technology is a potential tool to detect the progression of CCA, especially in the early stages of the disease.

Infrared spectroscopy coupled to cloud-based data management as a tool to diagnose malaria: a pilot study in a malaria-endemic country.

BACKGROUND: Widespread elimination of malaria requires an ultra-sensitive detection method that can detect low parasitaemia levels seen in asymptomatic carriers who act as reservoirs for further transmission of the disease, but is inexpensive and easy to deploy in the field in low income settings. It was hypothesized that a new method of malaria detection based on infrared spectroscopy, shown in the laboratory to have similar sensitivity to PCR based detection, could prove effective in detecting malaria in a field setting using cheap portable units with data management systems allowing them to be used by users inexpert in spectroscopy. This study was designed to determine whether the methodology developed in the laboratory could be translated to the field to diagnose the presence of Plasmodium in the blood of patients presenting at hospital with symptoms of malaria, as a precursor to trials testing the sensitivity of to detect asymptomatic carriers. METHODS: The field study tested 318 patients presenting with suspected malaria at four regional clinics in Thailand. Two portable infrared spectrometers were employed, operated from a laptop computer or a mobile telephone with in-built software that guided the user through the simple measurement steps. Diagnostic modelling and validation testing using linear and machine learning approaches was performed against the gold standard qPCR. Sample spectra from 318 patients were used for building calibration models (112 positive and 110 negative samples according to PCR testing) and independent validation testing (39 positive and 57 negatives samples by PCR). RESULTS: The machine learning classification (support vector machines; SVM) performed with 92% sensitivity (3 false negatives) and 97% specificity (2 false positives). The Area Under the Receiver Operation Curve (AUROC) for the SVM classification was 0.98. These results may be better than as stated as one of the spectroscopy false positives was infected by a Plasmodium species other than Plasmodium falciparum or Plasmodium vivax, not detected by the PCR primers employed. CONCLUSIONS: In conclusion, it was demonstrated that ATR-FTIR spectroscopy could be used as an efficient and reliable malaria diagnostic tool and has the potential to be developed for use at point of care under tropical field conditions with spectra able to be analysed via a Cloud-based system, and the diagnostic results returned to the user's mobile telephone or computer. The combination of accessibility to mass screening, high sensitivity and selectivity, low logistics requirements and portability, makes this new approach a potentially outstanding tool in the context of malaria elimination programmes. The next step in the experimental programme now underway is to reduce the sample requirements to fingerprick volumes.

The Upregulation of OCT4 in Acidic Extracellular pH is Associated with Gemcitabine Resistance in Cholangiocarcinoma Cell Lines.

Background: Cholangiocarcinoma (CCA), although is an uncommon liver cancer originating from bile duct epithelial cells, is one of the top 10 most fatal cancers. Chemoresistance is an unmet need always found in CCA patients. Tumor microenvironment conditions such as hypoxia, nutrient starvation and acidic extracellular pH play critical roles in chemoresistance and cancer progression. However, the effect of acidic extracellular pH on cellular response and chemoresistance in CCA has not been studied. Methods: Human CCA cell lines (KKU-M213, KKU-M055 and KKU-100) were cultured under acidic (pH 6.5) or non-acidic (pH 7.4) condition and were used for gene expression, doubling time and cytotoxicity assay. Results: The acidic extracellular pH (pH 6.5) significantly increased doubling times of CCA cell lines compared with non-acidic condition (pH 7.4). Interestingly, extracellular acid condition induced gemcitabine resistance in CCA cell lines. We showed that Octamer-binding transcription factor 4 (Oct4) was upregulated in these cell lines under extracellular acid condition. Conclusion: Our findings demonstrate that CCA cells can adapt to survive in acidic environment after which chemoresistance has been developed. Oct4 may be a key transcriptional regulator which mediates chemoresistance in response to acidic extracellular pH.

The development of simultaneous measurement of viral load and physical status for human papillomavirus 16 and 18 co-infection using multiplex quantitative polymerase chain reaction.

Persistent infection with human papillomavirus (HPV) type 16 and 18 is known to be a major risk factor for cervical cancer. Increased prevalence of co-infection with these high-risk types has been observed in pre-cancerous and cancerous tissues. The determination of physical status and copy numbers of viruses is therefore useful in clinical settings. A simple multiplex quantitative polymerase chain reaction (qPCR) for HPV16/HPV18 co-infection in one tube reaction was established in the present study using TaqMan®-based PCR for E2 and E6 viral DNA. The detection range was up to 106 copies with 100% specificity and high precision (CV of cycle time <0.5%). The analytical accuracy and robustness were verified by competitive assay using an unequal mixture of HPV16/HPV18 DNA. No significant effect was demonstrated when compared with the simplex qPCR. The detection of physical status was evaluated in cervical samples, including 5 pre-cancerous and 15 cancerous samples. No significant difference was observed between simplex and multiplex qPCR (P=0.372). In conclusion, the developed multiplex qPCR method successfully demonstrated the viral status of the common HPV types in one tube. This assay will facilitate viral assessment and monitoring of cervical cancer associated with HPV16 and HPV18 co-infection.

Aberrant methylation of HTATIP2 and UCHL1 as a predictive biomarker for cholangiocarcinoma.

Cholangiocarcinoma (CCA) is the most common primary liver cancer in Northeastern Thailand where liver fluke infection is highly endemic. Although aberrant DNA methylation in CCA has been reported by several investigators, little is known regarding the associations between them. In the present study, the results obtained from our previously published methylation array were analyzed and 10 candidate genes involved in DNA repair [protein phosphatase 4 catalytic subunit (PPP4C)], apoptosis [runt related transcription factor 3 (RUNX3), interferon regulatory factor 4 (IRF4), ubiquitin C­terminal hydrolase L1 (UCHL1) and tumor protein p53 inducible protein 3 (TP53I3)], cell proliferation [cyclin D2 (CCND2) and Ras association domain family member 1 (RASSF1)], drug metabolism [aldehyde dehydrogenase 1 family member A3 (ALDH1A3) and solute carrier family 29 member 1 (SLC29A1)] and angiogenesis [human immunodeficiency virus­1 tat interactive protein 2 (HTATIP2)] were selected for quantification of their methylation levels in 54 CCA and 19 adjacent normal tissues using methylation­sensitive high­resolution melting. The associations between the methylation status of the individual genes and clinical parameters were statistically analyzed. High methylation levels were observed in UCHL1, IRF4, CCND2, HTATIP2 and TP53I3. The median methylation level of UCHL1 was 57.3% (range, 3.15 to 88.7%) and HTATIP2 was 13.6% (range, 7.5 to 36.7%). By contrast, low methylation of HTATIP2 and UCHL1 was identified in adjacent normal tissues. The methylation status of HTATIP2 and UCHL1 was associated with patients' overall survival. CCA patients with high methylation of HTATIP2 and low methylation of UCHL1 exhibited longer overall survival. In addition, multivariate Cox regression analysis demonstrated that UCHL1 methylation was an independent factor for CCA with hazard ratio of 1.81 (95% confidence interval, 1.01­3.25) in high methylation group. The combination of HTATIP2 and UCHL1 methylation status strongly supported their potential predictive biomarker in which patients with CCA who had high methylation of HTATIP2 and low methylation of UCHL1 showed longer overall survival than those with low HTATIP2 methylation and high UCHL1 methylation. In conclusion, the present study revealed the value of aberrant DNA methylation of HTATIP2 and UCHL1, which may serve as a potential predictive biomarker for CCA.

High expression of CCDC25 in cholangiocarcinoma tissue samples.

Cholangiocarcinoma (CCA) is a malignant transformation of biliary epithelial cells. It is a slow growing tumor, but is also highly metastatic with a poor prognosis. Bile acids are known to transactivate the epidermal growth factor receptor (EGFR) in cholangiocytes and induce cyclooxygenase-2 expression. The protein expression profiles of bile acid-treated CCA cells were studied using a proteomic approach. To elucidate the possible mechanisms involved in the bile acid-mediated enhancement of CCA cell migration, the effects of six bile acids, including cholic, deoxycholic, taurocholic, taurodeoxycholic, glycocholic and glycodeoxycholic acid, on the migration of CCA cells were examined in vitro using wound healing assays. Subsequently, the possible proteins involved in enhanced CCA cell migration were investigated using a proteomic approach. Changes to the protein expression profiles of CCA cells following bile acid treatment was examined using two-dimensional electrophoresis and mass spectrometry. The results demonstrated that cholic and deoxycholic acid significantly enhanced the migration of CCA cells, compared with the treated MMNK-1 control cells. CCA cells had 77 overexpressed protein spots following cholic acid treatment, and 50 protein spots following deoxycholic acid treatment, compared with the treated MMNK-1 control cells. Liquid chromatography tandem-mass spectrometry analysis revealed that coiled-coil domain containing 25 (CCDC25) was significantly overexpressed in cholic acid-treated CCA cells compared with in cholic acid-treated control cells. When the expression levels of CCDC25 were investigated using western blot analysis, CCDC25 was demonstrated to be highly expressed in CCA tissues, but not in the adjacent non-cancerous tissue samples. The identified proteins were further analyzed for protein-chemical interactions using STITCH version 3.1 software. CCDC25 protein was identified to be associated with Son of sevenless homolog 1 and growth factor receptor-bound protein 2, which are involved in EGFR signaling. The results of the present study demonstrated that following cholic acid treatment, CCDC25 is overexpressed in CCA cells, which is associated with significantly enhanced cell migration. This suggests that CCDC25 is a potential therapeutic target for the treatment of patients with CCA.

Detection assay for HPV16 and HPV18 by loop­mediated isothermal amplification with lateral flow dipstick tests.

Cervical cancer is the third highest cause of death in developing countries and most commonly results from high­risk human papillomavirus (HR­HPV) infection. Among HR­HPV genotypes, HPV16 and HPV18 are the most prevalent in cervical cancers. Therefore, the present study aimed to develop a detection assay for HPV16 and HPV18 infection using loop­mediated isothermal amplification (LAMP) with lateral flow dipstick (LFD) tests. This assay is a simplified, user­friendly method for the visual detection of HPV genotypes. DNA was extracted from clinical tissue samples, and HPV genotyping was performed using nested polymerase chain reaction (PCR). The clinical samples were demonstrated to include 44 HPV16­positive, 18 HPV18­positive and 80 HPV­negative samples. All DNA samples were also used as templates for a LAMP reaction (30 min at 65˚C), and subsequently, a fluorescein isothiocyanate­labelled probe was hybridized with the reaction product. Finally, the LFD test was performed. The sensitivity of the LAMP­LFD test was higher than LAMP­turbidity, exhibiting up to 100­fold higher sensitivity for HPV16 and 10­fold higher sensitivity for HPV18. All HPV16 and HPV18­positive samples generated positive results in both assays; however, 22 samples detected as HPV­negative by LAMP­turbidity exhibited positive results by LAMP­LFD test (22 of 80 samples). Therefore, these samples were further examined using quantitative (q)PCR. The results demonstrated that 20 out of the 22 samples designated positive by LAMP­LFD, but negative by LAMP turbidity, gave a positive result with qPCR, while the remaining 2 samples were negative by qPCR. The present results suggested that LAMP­LFD provided higher sensitivity than LAMP­turbidity and nested PCR. Thus, the LAMP­LFD test developed in the present study might be useful for the detection of HPV16 and HPV18 in local hospitals.

Classification of Gemcitabine resistant Cholangiocarcinoma cell lines using synchrotron FTIR microspectroscopy.

Cholangiocarcinoma (CCA), a cancer of bile duct epithelium, is a major health problem in Thailand especially in the northeast. Overall treatment outcomes have not shown much improvement because the disease is usually detected at an advanced stage and often shows chemotherapeutic resistance. High-throughput Fourier Transform Infrared (FTIR) microspectroscopy can be used for cell classification and has the potential to diagnose cancer and possibly predict chemo-response. This study was aimed to differentiate gemcitabine-sensitive and gemcitabine-resistant induction in two CCA cell lines (KKU-M139 and KKU-M214) and xenograft tissues using synchrotron-FTIR microspectroscopy. Partial Least Squares Discriminant Analysis (PLS-DA) could discriminate between chemo-sensitive and chemo-resistant cells in the FTIR fingerprint spectral region (1800-1000 cm-1 ) with more than 90% sensitivity and specificity. The chemo-resistant and chemo-sensitive phenotypes were different in protein (amide I, amide II), lipids (carbonyl group and CH3 deformation) and phosphodiester from nucleic acids. Additionally, spectra from xenograft tissues showed similar results to the cell line study with marked differences between chemo-resistant and chemo-sensitive CCA tissues, and PLS-DA could discriminate the chemotherapeutic response with 98% sensitivity and specificity. This is the first study to demonstrate the use of FTIR microspectroscopy to assess chemo-response both in vitro and in vivo.

Thymosin ß10 as a predictive biomarker of response to 5-fluorouracil chemotherapy in cholangiocarcinoma.

UNLABELLED:  Introduction and aim. 5-Fluorouracil (5-FU) is the most commonly used chemotherapeutic drug in the treatment of cholangiocarcinoma (CCA). Since development of drug resistance to 5-FU in CCA patients is the primary cause of treatment failure, a better understanding of the mechanism of drug resistance of this cancer is essential to improve the efficacy of 5-FU in CCA therapy. MATERIAL AND METHODS: A 5-FU resistant CCA cell line (M214-5FUR) for a comparative chemo-resistance study was established. Real time RT-PCR was used to determine gene expression levels. Cell cytotoxicity was measured by the MTT assay. Protein expression levels were detected by the immunofluorescene method. RESULTS: It was found that 5-FU resistance was associated with the overexpression of T?10 in CCA cell lines. 5-FU treatment at various concentrations induced the expressions of T?10 and ABC transporters (ABCB1, ABCG2 ABCA3) in two CCA cell lines, KKU-M055 and KKU-M214. M214-5FUR, a 5-FU-resistant cell line, exhibited a 5-FU resistant phenotype with a 16-fold extremely high expression of T?10 and ABC transporters, as compared to the parental cells, KKU-M214. siRNA targeted to T?10 significantly reduced expression of ABC transporters tested in the M214-5FUR cells (P < 0.05). CONCLUSIONS: The present novel findingsof T?10 connected with drug resistance as shown in this study provides a new insight for the therapeutic value of T?10 as a predictive biomarker of 5-FU chemoresistance. Inhibiting T?10 may be a valuable adjunct for suppression of ABC transporters and sensitizing chemotherapy treatment, especially 5-FU in CCA patients.

Comparison of Automated and Conventional IHC Visual Scoring Analysis for MHC Class I and Tapasin Expression in Cervical Carcinoma.

BACKGROUND: Cervical cancer (CXCA) is the second most common cancer among women in Thailand and worldwide. Immune evasion caused by down-regulation of host immune responsive genes, such as MHC class I and loss of antigen processing machinery (APM), presents a capability leading to cancer development. Immunohistochemical staining (HC) is regarded as a common technique for protein marker detection in clinical laboratories. At present, IHC automation has been launched to facilitate the speed and feasibility to replace conventional IHC. However, evaluation of its use is still limited. OBJECTIVE: This study aimed to evaluate IHC scoring by automated visual analysis compared to conventional IHC analysis. MATERIAL AND METHOD: The paraffin-embedded tissues of 96 invasive CXCA were processed using a tissue microarray (TMA) platform followed by automated IHC staining of the anti-MHC class I (heavy chain, ß2M) and an APM-Tapasin expression. Conventional IHC and automated slide scanning with scoring visual analysis were compared. RESULTS: The results showed significant association between conventional and automated IHC evaluation (p-value > 0.05, Chi-square) for MHC class I and Tapasin stated in percentage of positive cancer cells, whereas intensity was found (p-value < 0.05, Chi-square) with moderate agreement (p-value < 0.001, kappa) 0.434-0.615 and 0.353-0.554, respectively. After calculated values, the results showed significant association between conventional and automated IHC evaluation (p-value > 0.05, Chi-square) for MHC class I and Tapasin with the highest agreement level (p-value < 0.001, kappa) of summation 0.595-0.755 and multiply scoring 0.633-0.689, respectively. CONCLUSION AND DISCUSSION: The automation softwarefor IHC scoring and interpretation can be used for the determination of MHC class I and Tapasin in CXCA. In addition, an antigen presentation pattern must be included to allow an accurate result for MHC class I in clinical use. An appropriate sample size and design of staging coverage as well as clinical prognosis outcomes of progression should be used infurther investigation.

The evaluation of loop-mediated isothermal amplification-quartz crystal microbalance (LAMP-QCM) biosensor as a real-time measurement of HPV16 DNA.

We have previously developed quartz crystal microbalance biosensor integrated with loop-mediated isothermal amplification (LAMP-QCM) for human papillomavirus (HPV) type58 DNA detection. Infection with HPV, particularly HPV16, remains a serious health problem due to its major risk factor contributing to cervical cancer. In the present study, LAMP-QCM biosensor was evaluated in terms of a quantitative assay for copy number of HPV16 DNA in cervical samples compared to quantitative PCR using TaqMan assay (TaqMan-qPCR). The detection limit of LAMP-QCM was found to be 10 fold more sensitive than TaqMan-qPCR with 100% specificity and 7.6% imprecision. Different plot of HPV16 DNA copy number using Bland-Altman analysis revealed 94% correlation between LAMP-QCM and qPCR. We therefore concluded that the developed LAMP-QCM biosensor provides a possible rapid and sensitive assay for HPV16 DNA quantification in a routine laboratory.

Targeting the ∆133p53 isoform can restore chemosensitivity in 5-fluorouracil-resistant cholangiocarcinoma cells.

Lack of the normal p53 transactivation domain, ∆133p53 isoform exhibits anti-p53 function. Many studies report the correlation between ∆133p53 expression and poor survival in various cancers, including cholangiocarcinoma (CCA), which is a cancer of the bile ducts. CCA almost always results in short survival times. The relevance of ∆133p53 to drug resistance in CCA is not yet well understood. This study aimed to demonstrate the association between ∆133p53 and 5-fluorouracil (5-FU) resistance in CCA. ∆133p53 protein was highly expressed in CCA patients with poor outcome compared to favorable outcome but was not statistically significant. However, a significant correlation was found between normalized ∆133p53 levels and 5-FU resistance which was defined by an ex vivo histoculture drug response assay (P=0.019). Two stable 5-FU-resistant CCA cell lines, KKU-M139R (IC50 38.8 µM) and KKU-M214R (IC50 39.5 µM), were used as a model to evaluate the role of ∆133p53. Increased ∆133p53 was correlated with 5-FU in a dose-dependent manner. The transient knockdown of ∆133p53 expression can restore drug sensitivity in both resistant CCA cells with 11- to 45-fold reduction of IC50 compared to control. Upon ∆133p53 silencing, apoptotic signaling was enhanced by the upregulation of Bax and downregulation of Bcl-2. Additionally, p21 and p27 were upregulated, resulting in cell cycle arrest at G2. Inhibition of colony formation and prolong doubling time were also observed. Our findings demonstrated that chemosensitivity can be modulated via targeting of ∆133p53 suggesting the potential use of ∆133p53 as a candidate for targeting therapy in CCA.

Silk fibroin/gelatin-chondroitin sulfate-hyaluronic acid effectively enhances in vitro chondrogenesis of bone marrow mesenchymal stem cells.

Tissue engineering is becoming promising for cartilage repair due to the limited self-repair capacity of cartilage tissue. We previously fabricated and characterized a three-dimensional silk fibroin/gelatin-chondroitin sulfate-hyaluronic acid (SF-GCH) scaffold and showed that it could promote proliferation of human bone marrow mesenchymal stem cells (BM-MSCs). This study aimed to evaluate its biological performance as a new biomimetic material for chondrogenic induction of BM-MSCs in comparison to an SF scaffold and conventional pellet culture. We found that the SF-GCH scaffold significantly enhanced the proliferation and chondrogenic differentiation of BM-MSCs compared to the SF scaffold and pellet culture in which the production of sulfated glycoaminoglycan was increased in concordance with the up-regulation of chondrogenic-specific gene markers. Our findings indicate the significant role of SF-GCH by providing a supportive structure and the mimetic cartilage environment for chondrogenesis which enables cartilage regeneration. Thus, our fabricated SF-GCH scaffold may serve as a potential biomimetic material for cartilage tissue engineering.

Establishment and characterization of gemcitabine-resistant human cholangiocarcinoma cell lines with multidrug resistance and enhanced invasiveness.

To establish and characterize the gemcitabine-resistant cholangiocarcinoma (CCA) cell lines, CCA KKU­M139 and KKU­M214 cell lines were exposed stepwisely to increasing gemcitabine (GEM). The resultant drug-resistant cell lines, KKU­M139/GEM and KKU­M214/GEM, retained the resistant phenotype in drug-free medium at least for 2 months. Sulforhodamine B assay demonstrated that KKU­M139/GEM and KKU­M214/GEM were 25.88- and 62.31-fold more resistant to gemcitabine than their parental cells. Both gemcitabine-resistant cell lines were cross-resistant to 5-fluorouracil (5-FU), doxorubicin and paclitaxel indicating their multidrug-resistant nature. Using reverse transcriptase-polymerase chain reaction (RT-PCR), real-time PCR and western blot analyses, gemcitabine-resistant cells showed upregulation of RRM1 and downregulation of hENT1 and dCK. In relation to multidrug resistance, these cell lines showed upregulation of multidrug resistance protein 1 (MRP1) leading to an increase of drug efflux. Using cell adhesion and Boyden chamber transwell assays, these cell lines also showed higher cell adhesion, migration and invasion capabilities via the activations of protein kinase C (PKC), focal adhesion kinase (FAK), extracellular signal-regulated kinase-1/2 (ERK1/2) and nuclear factor-κB (NF-κB). Higher activity of matrix metalloproteinase-9 (MMP-9) and urokinase plasminogen activator (uPA) was also observed by a gelatin zymography assay and a casein-plasminogen zymography assay. Flow cytometry analysis indicated the G2/M arrest regulated by downregulation of cyclin B1 and cyclin-dependent kinase 1 (Cdk1) resulted in an extended population doubling time. Using Annexin V/propidium iodide staining, evasion of apoptosis via an intrinsic pathway was observed in both cell lines in association with upregulation of Bcl-2 and downregulation of Bax. Interestingly, Fas was additionally downregulated in KKU­M214/GEM supporting the view of its higher GEM resistant characteristics. These findings indicate that long-term exposure of CCA cell lines to gemcitabine induce not only multidrug resistance but also enhance their invasiveness.

DNA methylation level of OPCML and SFRP1: a potential diagnostic biomarker of cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a malignancy of the bile duct epithelium which is caused by liver fluke infection. The clinical symptoms of CCA were revealed as the disease progresses to advanced stage. Thus, specific diagnostic biomarkers are important for this fatal disease. We applied methylation-sensitive high-resolution melting (MS-HRM) to quantify DNA methylation levels of opioid binding protein/cell adhesion molecule-like gene (OPCML) and Secreted frizzled-related protein 1 (SFRP1) in 73 primary CCA and 10 adjacent normal tissues and evaluated the sensitivity, specificity, and accuracy of the assay. The median methylation level of OPCML in CCA was 38.7 % (ranged from 0 to 82.2 %) and of SFRP1 was 31.5 % (ranged from 0 to 86.2 %). Methylation cutoff values of OPCML and SFRP1 derived from adjacent normal tissue were 6.90 and 10.44 %, respectively. With these cutoff values, the area under curve (AUC) of OPCML was 0.932 (95 % CI 0.878-0.986) and of SFRP1 was 0.951 (95 % CI 0.905-0.996). The sensitivity, specificity, and accuracy of OPCML were 89.04, 100, and 90.36 %, respectively, and of SFRP1 were 83.56, 100, and 85.54 %, respectively. In conclusion, the DNA methylation levels of OPCML and SFRP1 could be potential biomarkers for diagnosis of CCA with high specificity, sensitivity, and accuracy, in particular for biopsy specimens. Further validation in noninvasive samples such as serum or plasma is warranted for clinical applicability, especially as early diagnostic biomarkers.

Discrimination of micromass-induced chondrocytes from human mesenchymal stem cells by focal plane array-Fourier transform infrared microspectroscopy.

Rapid and sensitive methods for identifying stem cell differentiation state are required for facilitating future stem cell therapies. We aimed to evaluate the capability of focal plane array-Fourier transform infrared (FPA-FTIR) microspectroscopy for characterising the differentiation of chondrocytes from human mesenchymal stem cells (hMSCs). Successful induction was validated by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis for collagen and aggrecan expression as chondrocyte markers in parallel with the spectroscopy. Spectra derived from chondrocyte-induced cells revealed strong IR absorbance bands attributed to collagen near 1338 and 1234 cm(-1) and proteoglycan at 1245 and 1175-960 cm(-1) compared to the non-induced cells. In addition, spectra from control and induced cells are segregated into separate clusters in partial least squares discriminant analysis score plots at the very early stages of induction and discrimination of an independent set of validation spectra with 100% accuracy. The predominant bands responsible for this discrimination were associated with collagen and aggrecan protein concordant with those obtained from RT-PCR and Western blot techniques. Our findings support the capability of FPA-FTIR microspectroscopy as a label-free tool for stem cell characterization allowing rapid and sensitive detection of macromolecular changes during chondrogenic differentiation.