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Background and Objectives: Cervical cancer is one of the most common types of frequently found cancers in Thailand. One of the causative agents is the infection of the high-risk human papillomavirus (HPV) type 16 and 18. Traditional medicines are rich sources of bioactive compounds which are a valuable source for the development of novel cancer therapies. In this study, the therapeutic effects of 3 traditional medicines, KerraTM, KSTM, and MinozaTM, were studied on HeLa and CaSki cells. Materials and Methods: The effects of KerraTM, KSTM, and MinozaTM on cancer cells were evaluated through cytotoxicity and cell death assays. The infection assay using HPV-16 pseudovirus was also carried out. Results: All traditional medicines efficiently suppressed cell growths of HeLa and CaSki, with KerraTM being the most potent anticancer agent followed by KSTM and MinozaTM. KerraTM at 158 µg/mL and 261 µg/mL significantly increases the percentage inhibition of the HPV-16 pseudovirus infection in a pre-attachment step in a dose-dependent manner, while KSTM at 261 µg/mL efficiently inhibited viral infection in both pre-attachment and adsorption steps. However, KerraTM, KSTM, and MinozaTM at subtoxic concentrations could not reduce the viral E6 mRNA expressions of HPV-16 and HPV-18. Cell death assay by acridine orange/ethidium bromide showed that KerraTM increased population of dead cells in dose-dependent manner in both CaSki and HeLa. The percentage of secondary necrosis in KerraTM-treated CaSki was higher than that of HeLa cells, while the percentage of late apoptotic cells in HeLa was higher than that of CaSki, indicating that HeLa was more susceptible to KerraTM than CaSki. For KSTM and MinozaTM, these extracts at 250 µg/mL promoted autophagy over cell death. At 500 µg/mL, the percentage of dead cells in KerraTM was higher than that of KSTM and MinozaTM. Conclusions: KerraTM is a potent traditional medicine for promoting cancer cell death. KerraTM is possibly useful in the prevention and treatment of cervical cancer. Further investigation will be carried out to gain a better understanding of the biochemical mechanism and the pharmacological activity underlying this effect. [ABSTRACT FROM AUTHOR]

Peroxiredoxin 2 (PRDX2) is upregulated in various cancers including oral squamous cell carcinoma (OSCC). It is a known tumor promoter in some cancers, but its role in OSCC is unclear. This study aimed to investigate the effect of arecoline, an alkaloid of the betel nut, and human papillomavirus type 16 (HPV16) E6/E7 oncoproteins on induction of PRDX2 expression, and also the effects of PRDX2 overexpression in oral cell lines. Levels of PRDX2 protein were determined using western blot analysis of samples of exfoliated normal oral cells (n = 75) and oral lesion cells from OSCC cases (n = 75). Some OSCC cases were positive for HPV infection and some patients had a history of betel quid chewing. To explore the level of PRDX2 by western blot, the proteins were extracted from oral cell lines that were treated with arecoline or retroviruses containing HPV16 E6 gene and HPV16 E6/E7 expressing vector. For analysis of PRDX2 functions, cell proliferation, cell-cycle progression, apoptosis and migration was compared between oral cells overexpressing PRDX2 and cells with PRDX2-knockdown. PRDX2 expression levels tended to be higher in OSCC samples that were positive for HPV infection and had history of betel quid chewing. Arecoline treatment in vitro at low concentrations and overexpression of HPV16 E6 or E6/E7 in oral cells induced PRDX2 overexpression. Interestingly, in oral cells, PRDX2 promoted cell proliferation, cell-cycle progression (G2/M phase), cell migration and inhibited apoptosis. Upregulation of PRDX2 in oral cells was induced by arecoline and HPV16 oncoproteins and promoted growth of OSCC cells. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are small non-coding RNAs that function to down-regulate gene expression involving in various cellular processes related to carcinogenesis. Recently, miR-22 was identified as a tumor-suppressing miRNA in many human cancers. However, the regulatory mechanism and the specific function of this miRNA in cervical cancer remain unclear. In the present study, we carried out gene transfection, western blot and quantitative RT-PCR to explore the regulatory mechanism and the functional role of miR-22 in cervical cancer. We verified that miR-22 was down-regulated in cervical cancer tissues and cervical cancer cell lines relative to matched non-tumor tissues and normal human cervical keratinocyte line (HCK1T). By contrast, histone deacetylase 6 (HDAC6) was inversely correlated with miR-22 in both cervical tissues and cancer cell lines. Mechanically, HDAC6 was down-regulated by miR-22 at the post-transcriptional level, via a specific target site within the 3’UTR, identified by a luciferase reporter assay. Moreover, we also showed that the correlation between miR-22 and HDAC6 expression was regulated by an E6/p53 pathway in HCK1Ts expressing HPV16 E6. For functional study, an ectopic expression of miR-22 could inhibit cell proliferation and migration, and could induce apoptosis of cervical cancer cell lines. These findings demonstrated that miR-22 was down-regulated in cervical cancer and inversely collated with its downstream target HDAC6. MiR-22 acts as tumor suppressor by inhibiting proliferation and migration, and by inducing apoptosis of cervical cancer cell lines by targeting the 3’UTR of HDAC6. This newly identified E6/p53/miR-22/HDAC6 regulatory network might be a candidate therapeutic target for cervical cancer. [ABSTRACT FROM AUTHOR]

MicroRNA-21 (miR-21) is recognized as an oncomir and shows up-regulation in many types of human malignancy. The aim of this study was to investigate the association of miR-21 expression associated with HPV infection in normal and abnormal cervical tissues. Cervical tissue samples with different cytological or histopathological grades were investigated for HPV by PCR and for miR-21 and programmed cell death, protein 4 (PDCD4) expression using quantitative real-time PCR (qRT-PCR). Laser capture microdissection (LCM) of stromal and epithelial tissues and in situ hybridization (ISH) using locked nucleic acid (LNA) probes were performed on a subset of fixed specimens. Cell line experiments were conducted on fibroblasts stimulated in culture media from HeLa cells, which were then assessed for miR-21, PDCD4, IL-6 and α-SMA expression by qRT-PCR. Twenty normal cervical cell, 12 cervicitis, 14 cervical intraepithelial neoplastic I (CIN I), 22 CIN II-III and 43 cervical squamous cell carcinoma (SCC) specimens were investigated. miR-21 levels were significantly lower in normal than in abnormal tissues. The expression of miR-21 in HPV negative normal cytology was significantly lower than in HPV positive samples in abnormal tissue and SCC. The miR-21 expression was significantly higher in HPV negative cervicitis than HPV negative normal cells. LCM and ISH data showed that miR-21 is primarily expressed in the tumor-associated stromal cell microenvironment. Fibroblasts treated with HeLa cell culture media showed up-regulated expression of miR-21, which correlated with increased expression of α-SMA and IL-6 and with down-regulation of PDCD4. These results demonstrate that miR-21 is associated with HPV infection and involved in cervical lesions as well as cervicitis and its up-regulation in tumor-stroma might be involved in the inflammation process and cervical cancer progression. [ABSTRACT FROM AUTHOR]

In the early stages of human papillomavirus (HPV) infection, the viral proteins elicit specific immune responses that can participate to regression of ano-genital lesions. HPV E6 protein for instance can reduce type I interferon (IFN) including IFN-κ that is involved in immune evasion and HPV persistence. To evaluate the role of E2 protein in innate immunity in HPV16-associated cervical lesions, genome-wide expression profiling of human primary keratinocytes (HPK) transduced by HPV16 E2 was investigated using microarrays and innate immunity associated genes were specifically analyzed. The analyses showed that the expression of 779 genes was modulated by HPV16E2 and 92 of them were genes associated with innate immunity. Notably IFN-κ and STING were suppressed in HPK expressing the E2 proteins of HPV16 or HPV18 and the trans-activation amino-terminal domain of E2 was involved in the suppressive effect. The relationship between STING, IFN-κ and interferon stimulated genes (ISGs) in HPK was confirmed by gene silencing and real time PCR. The expression of STING and IFN-κ were further determined in clinical specimens by real time PCR. STING and IFN-κ were down-modulated in HPV positive low grade squamous intraepithelial lesions compared with HPV negative controls. This study demonstrates that E2 proteins of high risk HPV reduce STING and IFN-κ transcription and its downstream target genes that might be an immune evasion mechanism involved in HPV persistence and cervical cancer development. [ABSTRACT FROM AUTHOR]

Background: The variation of human papillomavirus (HPV) genes or HPV variants demonstrates different risks of cervical cancer. Mutation in the long control region (LCR) at YY1-motifs is one of the mechanisms for enhancing viral oncogene expression during the course of cancer cell progression. In Thai women, cervical cancers are almost always associated with HPV16 variant sub-lineage Asian (HPV16As); however, the mechanism involved remains elusive. The aim of this study was to understand further the oncogenic potential of HPV16As. Methods: A total of 82 HPV16-positive specimens from Thai women were selected from formalin-fixed paraffinembedded cervical tissues, and the full length E6 gene of each specimen was amplified and sequenced. LCRs of the HPV16As-positive cases were amplified and sequenced to analyze their polymorphisms. Transcriptional activities of the HPV16As LCRs were then compared with sub-lineage European (EUR), sub-lineage Asian-American 1 (AA1) and HPV16 prototype by insertion of the LCRs into the pGL3-Basic vector. Results: The HPV16 DNA sequences were classified as HPV16 prototype (18.3%), Asian (As, 61%), Asian American-1 (AA1, 8.5%), European (EUR, 7.3%), Asian African-2 (AFR2, 3.7%) and Java-135C (J135C, 1.2%). The prevalence of HPV16As was 30% in low-grade squamous intraepithelial lesion (LSIL), while that in high-grade squamous intraepithelial lesion (HSIL) and squamous cell cervical carcinoma (SCC) were 63.9% and 66.7%, respectively, which demonstrates a significant association of HPV16As with the disease severity. LCR polymorphisms from 43 HPV16As positive cases were analyzed by PCR-sequencing. Thirty-eight nucleotide variation positions spanned nucleotide positions 7157-82. Ten new mutations found in the HPV16As LCRs were located predominantly at the enhancer and proximal to the 3'-end of the early promoter. The LCRs of the common HPV16As, EUR and AA1 showed 5, 13 and 23-fold higher activity than the HPV16 prototype LCR, while those of the new nucleotide variations of As showed 19 (As-sv1) and 30 (As-sv14) -fold higher activity than the HPV16 prototype. Conclusions: HPV16As DNA sequence variation, especially at the proximal to early promoter in the LCR, enhances transcriptional activity. This could be one of the possible mechanisms for HPV16As-associated cervical cancer development. [ABSTRACT FROM AUTHOR]

Aim: This study investigated the utility of visual inspection with acetic acid (VIA) as a method for cervical cancer screening in Thailand and examined the relationship of VIA to high-risk human papillomavirus (HR-HPV) status. Methods: Cervical cells were collected from 160 patients receiving a Pap smear. VIA was performed on the cervix of the patients by application of 5% acetic acid. HPV screening of DNA extracted from cytology samples was performed by PCR using the GP5+/6+ primer system followed by reverse line blot hybridization genotyping. Results: The majority (96.9%) of the patients were diagnosed with normal or inflammatory cytologic changes. 32.8% of normal cytology and 42.0% of inflammation cases showed positive acetowhite staining. 3.1%, 38.1% and 42.5% of subjects were positive for an abnormal Pap test, VIA test, and HPV DNA, respectively. VIA demonstrated 50% sensitivity and 66.7% specificity for abnormal histology with PPV and NPV values of 50% and 66.7%, respectively, whereas HPV DNA test showed 100% sensitivity. HPV16 was the most common (54.4%) and HR-HPV was detected in 36.3% of all cases. 48.5% of HR-HPV positive and 36.8% of HR-HPV negative cervices stained with acetowhite following the VIA test. Conclusion: The VIA test is a simple method for cervical cancer screening; however, a significant proportion of patients with normal or inflammatory cytology were positive by this test. Further, HR-HPV in women without acetowhite staining was demonstrated. Therefore, some form of HR-HPV detection test may be required for combination with cervical cell screening even in low-resource nations. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To compare the clearance rate of HPV infection among women aged older than 30years with biopsy-confirmed cervical low-grade squamous intraepithelial lesions (LSIL) 1year after cryotherapy with the spontaneous clearance rate (observation). Method: HPV DNA typing by polymerase chain reaction and reverse line blot hybridization were used to identify 14 high-risk types and 23 low-risk types. HPV DNA sequencing was also used for other types. Result: Between December 2007 and March 2009, 100 women were recruited to the study and 60 cases had positive results on HPV testing. Twenty-nine patients were randomly allocated to the cryotherapy group and 31 to the observation group. At 1year, 89.7% (26/29; 95% CI, 78.6–100%) of the cryotherapy group and 90.3% (28/31; 95% CI, 79.9–100%) of the observation group had negative results on HPV testing (0.6% difference; 95% CI, –15.8 to 14.6%, P =0.94). Conclusion: Cryotherapy failed to increase the clearance of prevalent HPV infections among women with LSIL, although in both arms the clearance rates were above 80%. However, in coupling with visual inspection with acetic acid as a single visit approach, its effect on prevention of HSIL and cervical cancer is still promising. Therefore, cryotherapy should not be withdrawn from such programs. (ClinicalTrials.gov Identifier: NCT00566579). [Copyright &y& Elsevier]

Regardless of the prophylactic vaccine accessibility, persistent infections of high-risk human papillomaviruses (hr-HPVs), recognized as an etiology of cervical cancers, continues to represent a major health problem for the world population. An overexpression of viral early protein 6 (E6) is linked to carcinogenesis. E6 induces anti-apoptosis by degrading tumor suppressor proteins p53 (p53) via E6-E6-associated protein (E6AP)-mediated polyubiquitination. Thus, the restoration of apoptosis by interfering with the E6 function has been proposed as a selective medicinal strategy. This study aimed to determine the activities of andrographolide (Androg) on the disturbance of E6-mediated p53 degradation in cervical cancer cell lines using a proteomic approach. These results demonstrated that Androg could restore the intracellular p53 level, leading to apoptosis-induced cell death in HPV16-positive cervical cancer cell lines, SiHa and CaSki. Mechanistically, the anti-tumor activity of Androg essentially relied on the reduction in host cell proteins, which are associated with ubiquitin-mediated proteolysis pathways, particularly HERC4 and SMURF2. They are gradually suppressed in Androg-treated HPV16-positive cervical cancer cells. Collectively, the restoration of p53 in HPV16-positive cervical cancer cells might be achieved by disruption of E3 ubiquitin ligase activity by Androg, which could be an alternative treatment for HPV-associated epithelial lesions. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV), Epstein-Barr virus (EBV) and herpes simplex virus (HSV) cause sexually transmitted diseases (STDs) that are frequently found in men who have sex with men (MSM) with human immunodeficiency viral (HIV) infection.Methods: This study investigated the prevalence of infection and anatomical site distribution of these viruses in asymptomatic MSM. DNA, extracted from cells collected from the anorectum, oropharynx and urethra of 346 participants, was investigated for the presence of EBV, HPV and HSV using real-time PCR. Demographic data from the participants were analyzed.Results: All three viruses were found in all sampled sites. EBV was the commonest virus, being detected in the anorectum (47.7% of participants), oropharynx (50.6%) and urethra (45.6%). HPV and HSV were found in 43.9% and 2.9% of anorectum samples, 13.8% and 3.8% of oropharynx samples and 25.7% and 2% of urethra samples, respectively. HPV infection of the anorectum was significantly associated with age groups 21-30 (odds = 3.043, 95% CI = 1.643-5.638 and P = 0.001) and 46-60 years (odds = 2.679, 95% CI = 1.406-5.101 and P = 0.03). EBV infection of the urethra was significantly correlated with age group 21-30 years (odds = 1.790, 95% CI = 1.010-3.173 and P = 0.046). EBV/HPV co-infection of the anorectum (odds = 3.211, 95% CI = 1.271-8.110, P = 0.014) and urethra (odds = 2.816, 95% CI = 1.024-7.740, P = 0.045) was also associated with this age group. Among HIV-positive MSM, there was a significant association between age-group (odds = 21.000, 95% CI = 1.777-248.103, P = 0.016) in HPV infection of the anorectum. A failure to use condoms was significantly associated with HPV infection of the anorectum (odds = 4.095, 95% CI = 1.404-11.943, P = 0.010) and urethra (odds = 7.187, 95% CI = 1.385-37.306, P = 0.019). Similarly, lack of condom use was significantly associated with EBV infection of the urethra (odds = 7.368, 95% CI = 1.580-34.371, P = 0.011).Conclusion: These results indicate that asymptomatic MSM in Northeast Thailand form a potential reservoir for transmission of STDs, and in particular for these viruses. [ABSTRACT FROM AUTHOR]

HPV16 Asian variant (HPV16As) containing E6D25E oncogene, is commonly associated with cervical cancers of Asian populations. To explore a mechanism of E6D25E oncoprotein in carcinogenesis, we compared protein profiles in human keratinocytes expressing E6D25E with E6 of HPV16 prototype (E6Pro). A human cervical keratinocyte cell line, HCK1T, was transduced with retroviruses containing E6D25E or E6Pro genes. Biological properties of E6D25E or E6Pro transduced HCK1T cells were characterized. Protein profiles of the transduced HCK1T cells were analyzed using 2D-PAGE and characterized by mass spectrometry and western blotting. Reactomes of modulated proteins were analyzed by using the Reactome Knowledgebase. The E6D25E and E6Pro oncoproteins were comparable for their abilities to degrade p53 and suppress the induction of p21, and induce cell proliferation. Interestingly, the protein profiles of the HCK1T cells transduced with E6D25E showed specific proteomic patterns different from those with E6Pro. Among altered proteins, more than 1.5-fold up- or down- regulation was observed in E6D25E-expressing cells for gp96 and keratin7 which involved in activation of TLR signaling and transformation of squamocolumnar junction cells, respectively. This report describes new cellular proteins specifically targeted by E6D25E oncoprotein that may contribute to impair immune response against viral infection and cell transformation associated with oncogenic property of HPV16As variant. [ABSTRACT FROM AUTHOR]

Background Persistent infection with EBV has been linked to the development of malignancies including HPV-associated cervical carcinoma. However, the role of EBV in HPV-associated cervical cancer is still poorly understood. Objective To determine the possible contributing role of EBV in HPV-associated cervical carcinogenesis according to HPV genotypes, HPV genome status and EBV localization. Study design Cervical tissues, including 82 with no squamous intraepithelial lesions (noSILs), 85 low-grade SILs (LSILs), 85 high grade SILs (HSILs) and 40 squamous cell carcinoma samples (SCC) were investigated using PCR and dot blot hybridization for EBV detection and PCR and reverse line blot hybridization for HPV genotyping. The amplification of papillomavirus oncogene transcripts assay and in situ hybridization were used to determine HPV physical status and EBV EBER localization, respectively. Results EBV was detected increasingly from noSIL (13.4%), LSIL (29.4%) to HSIL (49.4%) samples. The prevalence of HPV–EBV co-infection was significantly higher in any grade of lesion than in noSIL samples ( p < 0.05) including noSIL (1.2%; 95% confidence intervals [CI] = 0.0–3.6%, relative risk [RR] = 1), LSIL (18.8%, 95% CI = 10.5–27.1%, RR = 15.4), HSIL (41.2%, 95% CI = 30.7–51.6%, RR = 33.8) and SCC (30.0%, 95% CI = 15.8–44.2%, RR = 24.6). Interestingly, HPV–EBV co-infection was more common in cases with episomal forms of high-risk (HR) HPV whereas HPV alone was more common in cases with integrated HR-HPV. In addition, EBER staining demonstrated that EBV was mainly present in infiltrating lymphocytes. Conclusion Infiltrating EBV-infected lymphocytes may play a role in cancer progression of cervical lesion containing episomal HR-HPV. [ABSTRACT FROM AUTHOR]