Zeni Wu

Complete Genome Analysis of Coxsackievirus A2, A4, A5, and A10 Strains Isolated from Hand-Foot-and-Mouth Disease Patients in China Revealing Frequent Recombination of Human Enterovirus A

ABSTRACT Coxsackievirus (CV) strains CVA2, CVA4, CVA5, and CVA10 were isolated from patients with hand, foot, and mouth disease during a 2009 outbreak in China. Full genome sequences for four representative strains, CVA2/SD/CHN/09 (A2SD09), CVA4/SZ/CHN/09 (A4SZ09), CVA5/SD/CHN/09 (A5SD09), and CVA10/SD/CHN/09 (A10SD09), were determined. Phylogenetic and recombination analyses of the isolates by comparison with human enterovirus A prototype strains revealed that genetic recombination occurred during cocirculation of the viruses. The A2SD09 and A4SZ09 strains were most closely related to their corresponding prototype strains in the capsid region but shared noncapsid sequences with each other. Similarly, strains A5SD09 and A10SD09 had serotype-specific homology for the capsid proteins but shared noncapsid sequences with each other. Phylogenetic analyses of the four isolates with homotypic strains showed that CVA2 strains were divided into five genotypes. The A2SD09 strain clustered with Mongolia strains isolated in 2003, forming genotype V. The A4SZ09 strain and other isolates from mainland China and Taiwan clustered with genotype III strains and are likely related to strains that circulated in Europe and Mongolia. The A5SD09 strain is closely related to other Chinese strains isolated in 2008. The A10SD09 isolate, together with other Chinese strains isolated since 2004, formed a distinct lineage that was likely imported from Japan and South Korea. This study shows that natural recombination is a frequent event in human enterovirus A evolution. More comprehensive surveillance of enteroviruses that focus not only on EV71 or CVA16 is needed for us to understand the molecular epidemiology of enteroviruses and to track recombination events which may ultimately affect the virulence of viruses during outbreaks.

Crystal Structures of Enterovirus 71 3C Protease Complexed with Rupintrivir Reveal the Roles of Catalytically Important Residues

ABSTRACT EV71 is the primary pathogenic cause of hand-foot-mouth disease (HFMD), but an effective antiviral drug currently is unavailable. Rupintrivir, an inhibitor against human rhinovirus (HRV), has potent antiviral activities against EV71. We determined the high-resolution crystal structures of the EV71 3Cpro/rupintrivir complex, showing that although rupintrivir interacts with EV71 3Cpro similarly to HRV 3Cpro, the C terminus of the inhibitor cannot accommodate the leaving-group pockets of EV71 3Cpro. Our structures reveal that EV71 3Cpro possesses a surface-recessive S2′ pocket that is not present in HRV 3Cpro that contributes to the additional substrate binding affinity. Combined with mutagenic studies, we demonstrated that catalytic Glu71 is irreplaceable for maintaining the overall architecture of the active site and, most importantly, the productive conformation of catalytic His40. We discovered the role of a previously uncharacterized residue, Arg39 of EV71 3Cpro, that can neutralize the negative charge of Glu71, which may subsequently assist deprotonation of His40 during proteolysis.

Evaluation of p16/Ki-67 dual staining in detection of cervical precancer and cancers: a multicenter study in China

Purpose To analyze the clinical performance of p16/Ki-67 dual-stained cytology identifying high-grade cervical intraepithelial neoplasia (CIN2+) in Chinese women. Methods 1079 women attending ongoing cervical cancer screening and 211 “enriched” women aged ≥30yrs with biopsy-confirmed CIN2+ from five Chinese hospitals were enrolled during year 2014-2015. Cervical specimens were collected for high-risk human papillomavirus (HR-HPV) DNA analysis, Liquid-based cytology (LBC) and p16/Ki-67 dual staining. Colposcopy and biopsy were performed on women with any abnormal result. Results p16/Ki-67 positivity increased with histologic severity. It was 18.4%(183/996) in normal histology, 54.0%(34/63) in CIN1, 81.0%(34/42) in CIN2, 93.3%(111/119) in CIN3, 71.4% (5/7) in adenocarcinoma and 95.2%(60/63) in squamous cell carcinoma. Compared with the HR-HPV negatives, p16/Ki-67 expression was significantly higher in the HPV16/18 positive (OR: 35.45(95%CI: 23.35-53.84)) and other 12 HR-HPV types positive group (OR: 8.01(95%CI: 5.81-11.05). The sensitivity and specificity of p16/Ki-67 to detect CIN2+ in the entire population were 90.9% and 79.5%, respectively. In women with ASC-US and LSIL, sensitivity and specificity for detection of CIN2+ were 87.5% and 66.4%, respectively, with a referral rate of 43.8%. In women who tested positive for HR-HPV, sensitivity and specificity of dual-staining for detection of CIN2+ were 92.7% and 52.7%, respectively, and the referral rate was 68.7%. Conclusions p16/Ki-67 dual-stained cytology provided a high sensitivity and moderate specificity to detect underlying cervical precancer and cancers in various settings, and might be considered as an efficient screening tool in China.

The association between human papillomavirus (HPV) 16, HPV18, and other HR-HPV viral load and the histological classification of cervical lesions: Results from a large-scale cross-sectional study.

The relationship between HPV viral load and histological grades in the development of cervical cancer is in argument. It is helpful to better understand the association by quantitatively detecting viral load of HPV16, 18, and a pool of 12 other high‐risk HPV type (OT) independently on the samples of precancer and cancer. A cross‐sectional study was performed in five medical centers of China. Histological diagnosis made by local pathologists was adjudicated via a pathology expert panel. A fully automated real‐time PCR test was used for the measurement of HPV16, 18, OT, and human β‐globin gene. A total of 2,513 women [1,341 normal, 209 low grade intraepithelial lesion (LSIL), 392 high grade intraepithelial lesion (HSIL), 520 squamous cell carcinoma (SCC), and 51 adenocarcinoma (ADC)] were included. There is a linear increase in the total 14 HPV viral load with histological grade from normal to SCC. This trend was not observed in HPV18 infection but HPV16. The viral load for OT was low in normal, peaked in LSIL and HSIL, and declined in SCC and ADC. In the co‐infection of HPV16 and HPV18, HPV16 viral load was significantly higher than HPV18 in LSIL and HSIL. In co‐infection of HPV16 and OT, higher HPV16 viral load was also seen in SCC and ADC. Viral load of HPV16 increases with cervical lesion grade and is predominant in cervical cancer. HPV18 viral load is low in precancer, but going up in cancer. OT viral load shows inverse trend of HPV18. J. Med. Virol. 89:535–541, 2017.

Elevated Expression of Human Papillomavirus-16/18 E6 Oncoprotein Associates with Persistence of Viral Infection: A 3-Year Prospective Study in China

Background: An association between high-risk human papillomavirus (HR-HPV) oncoprotein expression and viral persistence has been suggested by the outcome of etiology studies, but there are no epidemiologic studies evaluating that link. Methods: We performed a 3-year prospective study in which 2,498 Chinese women ages 25 to 65 years were screened by six screening tests, including the OncoE6 Cervical Test (Arbor Vita Corporation) in 2011 (baseline). Six-hundred and ninety women who were positive for any of the tests and a random sample of 164 women with all negative results received colposcopy, and cervical specimens for the cobas 4800 HPV test (“cobas,” Roche Molecular Systems) were collected before colposcopy; of this group, 737 cervical specimens were collected to perform cobas and OncoE6 Cervical Test in 2014 (follow-up). Twenty-four cases of HPV16/18 E6 positives and 204 selected controls at baseline, 13 cases of HPV16/18 E6 positive and another 204 selected controls at follow-up were analyzed separately using unconditional logistical regression models to estimate ORs and 95% confidence intervals (CI). Results: Compared with women who were HPV16 E6 oncoprotein negative at baseline, women in the E6-positive group had a much higher risk of HPV persistence (adjusted OR, 54.64; 95% CI, 7.19–415.09) at 3-year follow-up; a statistically strong association was also found between HPV16/18 HPV persistence and E6 oncoprotein expression detected at follow-up (adjusted OR, 360.57; 95% CI, 28.30–4,593.55). Conclusions: A single detection of HPV16/18 E6 oncoprotein expression was strongly associated with viral persistence. Impact: HPV16/18 E6 oncoprotein constitutes a marker for risk of HPV persistence. Cancer Epidemiol Biomarkers Prev; 25(7); 1167–74. ©2016 AACR.

Stability Study of Cervical Specimens Collected by Swab and Stored Dry Followed by Human Papillomavirus DNA Detection Using the cobas 4800 Test.

ABSTRACT Safer, more convenient methods for cervical sample collection and storage are necessary to facilitate human papillomavirus (HPV) DNA testing in low-resource settings. Our study aimed to evaluate the stability of cervical specimens collected with dry swabs and stored dry, compared to liquid-based cytology (LBC) samples, as detected by HPV DNA testing. Women with abnormal cytological findings or HPV-positive results at colposcopy were recruited from the West China Second University Hospital, Sichuan University, between October 2013 and March 2014. From each woman, physicians collected cervical specimens with a swab placed into a Sarstedt tube and a CytoBrush placed into LBC medium. Samples were randomly assigned to be stored at uncontrolled ambient temperature for 2, 7, 14, or 28 days and then were tested for 14 high-risk HPV (HR-HPV) types using the cobas HPV test. The rates of agreement between dry swab and LBC samples for any HR-HPV type, HPV16, HPV18, and the 12 pooled HR-HPV types were 93.8%, 97.8%, 99.4%, and 93.2%, respectively, with kappa values of 0.87 (95% confidence interval [CI], 0.83 to 0.91), 0.94 (95% CI, 0.91 to 0.97), 0.94 (95% CI, 0.87 to 1.00), and 0.86 (95% CI, 0.82 to 0.90). The performance of swab samples for detection of cervical precancerous lesions by means of cobas HPV testing was equal to that of LBC samples, even with stratification by storage time. Dry storage of swab-collected cervical samples can last for 1 month without loss of test performance by cobas HPV testing, compared to LBC samples, which may offer a simple inexpensive approach for cervical cancer screening in low-resource settings.

p16/Ki-67 co-expression associates high risk human papillomavirus persistence and cervical histopathology: a 3-year cohort study in China

Purpose To evaluate the association of p16/Ki-67 co-expression and persistence of high-risk human papillomavirus (HR-HPV) infection as well as cervical abnormalities. Methods We performed a 3-year cohort study among which 2498 Chinese women aged 25 to 65 years were screened by different HPV tests in 2011. 690 women who were positive at any of the tests and a random sample of 164 women with all negative results received colposcopy, cervical specimens for cobas HPV test (Roche diagnostics) were collected before colposcopy; of this group, 737 cervical specimens were collected to perform cobas, Liquid-based cytology, HPV E6 test (Arbor Vita Corporation) and p16/Ki-67 dual staining (Roche diagnostics) in 2014. Colposcopy and biopsies was performed on women with any abnormal result. Results Compared to women without HR-HPV persistent infection, women in the HR-HPV persistence group had a higher risk of p16/Ki-67 positive, with an adjusted Odds Ratio(OR) and 95% confidence interval (CI) of 6.29 (4.07-9.72); moreover, adjusted odds ratio for women who had HPV16/18 persistent infection was nearly 4-folder higher than women with other 12 HR-HPV persistent infection (adjusted OR = 17.15, 95% CI: 7.11-41.33 vs adjusted OR = 4.68, 95% CI: 2.89-7.58). Additionally, p16/Ki-67 positivity rate significantly increased with the severity of the cytological and histological abnormalities, and resulted strongly associated with a CIN2+ diagnosis (OR = 16.03, 95% CI: 4.46-57.59). Conclusions p16/Ki-67 co-expressions associated strongly with HR-HPV persistence, especially with HPV16/18, and the presence of a CIN2+ lesion. Therefore, p16/Ki-67 could be considered as a suitable biomarker for cervical cancer screening, particularly in HPV-based screening programs.

Clinical evaluation of human papillomavirus 16/18 oncoprotein test for cervical cancer screening and HPV positive women triage: Evaluation of OncoE6 for screening and triage

HPV‐16 and −18 account for about 80% of cervical cancers. We evaluated the performance of HPV‐16/18 oncoprotein to predict precancer and cancer in corresponding tissue biopsy specimens. 1,008 women attending cervical cancer screening program and 638 women referred to colposcopy with biopsy‐confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+) from 4 hospitals were recruited (1,646 in total). All women were tested OncoE6 (AVC), Liquid‐Based Cytology (Hologic) and cobas HPV test (Roche). Colposcopy was performed on women with any abnormal results. The final diagnoses were based on a consensus panel review of the histology. There were 919 normal, 69 CIN1, 53 CIN2, 91 CIN3,474 squamous cell carcinoma(SCC) and 40 adenocarcinoma (ADC) cases, the prevalence of OncoE6 was 1.7%, 10.1%, 13.2%, 44.0%, 80.4% and 65.0%, respectively. The percent positive for cobas was higher than that of OncoE6 in detection of HPV16/18 in entire population (p < 0.001). However, the disparity of positive rate between these two tests became tiny among cervical cancer patients (CIN2: 26.4% vs. 13.2%, CIN3: 73.6% vs. 44.0%, SCC: 84.0% vs. 80.4%, ADC: 67.5% vs. 65.0%). OncoE6 was less sensitive than cobas (73.9% vs. 93.6%, p < 0.001), but more specific (97.1% vs. 75.4%, p < 0.001) for CIN3+ in entire population; OncoE6 yielded a sensitivity of 77.7% and a specificity of 91.0% for CIN3+ among cobas positive women, which can reduce nearly half of the colposcopy referral numbers. OncoE6 can be considered as a useful tool for cervical cancer screening and a potential powerful biomarker for HPV positive triage.

The association between human papillomavirus 16, 18 DNA load and E6 protein expression in cervical intraepithelial neoplasia and cancer

BACKGROUND It has been reported that high HPV DNA load and elevated E6 protein expression correlate with cervical cancer, but no epidemiological study has been performed. OBJECTIVES To assess the association between type-specific HPV DNA load and presence of E6 protein in cervical intraepithelial neoplasia and cancer. STUDY DESIGN This study was a cross-sectional multicenter study performed between 2013 and 2017. A total of 1717 women (normal histopathology: n = 916; CIN1: n = 94; CIN2: n = 63; CIN3: n = 130; SCC: n = 474; adenocarcinoma: n = 40) were included. HPV DNA load and presence of E6 protein were detected. DNA load was measured as log copies/10,000 cells. RESULTS The HPV16/18-E6 positivity rates increased from negative for DNA to the highest load grade. Compared to the HPV16 DNA negatives, women with low (RR = 31.5, 95%CI = 18.9-52.5), medium-low (RR = 133.5, 95%CI = 77.3-230.7), medium-high (RR = 247.9, 95%CI = 134.9-455.6) and high DNA loads (RR = 677.9, 95%CI = 301.6-1523.7) had increasingly higher relative ratios of HPV16-E6 expression. The association of HPV18-E6 with its DNA load was also significant for low (RR = 27.9, 95%CI = 10.4-74.9), medium-low (RR = 89.0, 95%CI = 32.8-241.3), medium-high (RR = 276.8, 95%CI = 76.7-998.9) and high grade (RR = 441.2, 95%CI = 97.7-1992.4). The positivity rates of both HPV16 DNA and E6 protein increased consistently with the severity of diseases from normal histopathology to SCC. Unlike HPV16, the trends of HPV18 DNA and E6 protein fluctuated consistently among women from normal histopathology to cancer. DNA load in E6-positive women was significantly higher than E6-negative for both types. CONCLUSIONS There is a type-dependent association between HPV16/18 DNA load and E6 protein; our study furthers the understanding of the natural history of cervical cancer.

A cocktail of p16 INK4a and Ki-67, p16 INK4a and minichromosome maintenance protein 2 as triage tests for human papillomavirus primary cervical cancer screening

Most human papillomavirus (HPV) infections are transient and additional triage approaches should be built after HPV-based primary cervical cancer screening. We evaluated the accuracy of p16/Ki-67 and p16/mcm2 dual staining as biomarkers for triaging HPV positive women in China. 4070 participants aged 35 to 64 years attending ongoing cervical cancer screening were enrolled in 2015-2016. Cervical exfoliated cells were collected for HPV DNA analysis and the residual positive specimens were tested for liquid-based cytology and biomarkers. Women infected with HPV 16/18 type or other 12 high-risk HPV types with abnormal cytology results received colposcopy. We found the positive rates of both biomarkers increased significantly with histology severity. p16/Ki-67 positivity in HPV16/18 group, other 12 high-risk HPV group and HPV negative group was 50.0%, 33.7% and 8.9%, respectively. The corresponding p16/mcm2 positivity was 70.0%, 56.3% and 6.7%, respectively. The sensitivity and specificity of p16/Ki-67 for CIN2+ in all HPV-positive women were 91.7% and 63.5%, with a referral rate of 36.2%, while p16/mcm2 were 87.5% and 42.1%, with a referral rate of 58.4%, respectively. The sensitivity of p16/Ki-67 increased to 95.8% for CIN2+ and 100% for CIN3+ when combined with high-grade cytology, without decrease in specificity. Our studies suggest that p16/Ki-67 is an efficient triaging biomarker for HPV-positive women and could reduce colposcopy workload. p16/mcm2 is more sensitive compared with cytology for identifying cervical lesions.