Large-scale proteomics reveals precise biomarkers for detection of ovarian cancer in symptomatic women.

Ovarian cancer is the 8th most common cancer among women and has a 5-year survival of only 30-50%. While the survival is close to 90% for stage I tumours it is only 20% for stage IV. Current biomarkers are not sensitive nor specific enough, and novel biomarkers are urgently needed. We used the Explore PEA technology for large-scale analysis of 2943 plasma proteins to search for new biomarkers using two independent clinical cohorts. The discovery analysis using the first cohort identified 296 proteins that had significantly different levels in malign tumours as compared to benign and for 269 (91%) of these, the association was replicated in the second cohort. Multivariate modelling, including all proteins independent of their association in the univariate analysis, identified a model for separating benign conditions from malign tumours (stage I-IV) consisting of three proteins; WFDC2, KRT19 and RBFOX3. This model achieved an AUC of 0.92 in the replication cohort and a sensitivity and specificity of 0.93 and 0.77 at a cut-off developed in the discovery cohort. There was no statistical difference of the performance in the replication cohort compared to the discovery cohort. WFDC2 and KRT19 have previously been associated with ovarian cancer but RBFOX3 has not previously been identified as a potential biomarker. Our results demonstrate the ability of using high-throughput precision proteomics for identification of novel plasma protein biomarker for ovarian cancer detection.

Toward ovarian cancer screening with protein biomarkers using dried, self-sampled cervico-vaginal fluid.

Early detection is key for increased survival in ovarian cancer, but no general screening program exists today due to lack of biomarkers and overall cost versus benefit over traditional clinical methods. Here, we used dried cervico-vaginal fluid (CVF) as sampling matrix coupled with mass spectrometry for detection of protein biomarkers. We find that self-collected CVF on paper cards yields robust results and is suitable for high-throughput proteomics. Artificial intelligence-based methods were used to identify an 11-protein panel that separates cases from controls. In validation data, the panel achieved a sensitivity of 0.97 (95% CI 0.91-1.00) at a specificity of 0.67 (0.40-0.87). Analyses of samples collected prior to development of symptoms indicate that the panel is informative also of future risk of disease. Dried CVF is used in cervical cancer screening, and our results opens the possibility for a screening program also for ovarian cancer, based on self-collected CVF samples.

Next Generation Plasma Proteomics Identifies High-Precision Biomarker Candidates for Ovarian Cancer.

BACKGROUND: Ovarian cancer is the eighth most common cancer among women and has a 5-year survival of only 30-50%. The survival is close to 90% for patients in stage I but only 20% for patients in stage IV. The presently available biomarkers have insufficient sensitivity and specificity for early detection and there is an urgent need to identify novel biomarkers. METHODS: We employed the Explore PEA technology for high-precision analysis of 1463 plasma proteins and conducted a discovery and replication study using two clinical cohorts of previously untreated patients with benign or malignant ovarian tumours (N = 111 and N = 37). RESULTS: The discovery analysis identified 32 proteins that had significantly higher levels in malignant cases as compared to benign diagnoses, and for 28 of these, the association was replicated in the second cohort. Multivariate modelling identified three highly accurate models based on 4 to 7 proteins each for separating benign tumours from early-stage and/or late-stage ovarian cancers, all with AUCs above 0.96 in the replication cohort. We also developed a model for separating the early-stage from the late-stage achieving an AUC of 0.81 in the replication cohort. These models were based on eleven proteins in total (ALPP, CXCL8, DPY30, IL6, IL12, KRT19, PAEP, TSPAN1, SIGLEC5, VTCN1, and WFDC2), notably without MUCIN-16. The majority of the associated proteins have been connected to ovarian cancer but not identified as potential biomarkers. CONCLUSIONS: The results show the ability of using high-precision proteomics for the identification of novel plasma protein biomarker candidates for the early detection of ovarian cancer.

HPV viral load in self-collected vaginal fluid samples as predictor for presence of cervical intraepithelial neoplasia.

OBJECTIVE: This study was performed to evaluate the use of high-risk HPV (hrHPV) viral load in screening tests for cervical cancer to predict persistent infection and presence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+). METHODS: We followed women between 30 and 60 years of age who performed self-sampling of vaginal fluid and subsequently a hrHPV test. Women who were hrHPV positive in their screening test repeated the hrHPV test 3-6 months later and were included in the present study. RESULTS: Our results show that women with a persistent HPV16 infection had higher HPV viral load in their primary screening test than women with transient infections (p = 5.33e-03). This was also true for sum of viral load for all hrHPV types in the primary screening test (p = 3.88e-07). 48% of women with persistent HPV16 infection and CIN2+ had an increase in HPV16 titer in the follow-up test, as compared to only 20% of women with persistent infection but without CIN2+ lesions. For the sum of all hrHPV types, 41% of women with persistent infection and CIN2+ had an increase in titer as compared to 26% of women without CIN2 + . CONCLUSIONS: The results show that hrHPV viral load in the primary screening HPV test is associated with the presence of CIN2+ and could be used in triaging hrHPV positive women for different follow-up strategies or recall times. Serial testing of hrHPV viral load has the potential to distinguish women with CIN2+ lesions from women with persistent infection but without CIN2+ lesions.

Clinical validation of the HPVIR high-risk HPV test on cervical samples according to the international guidelines for human papillomavirus DNA test requirements for cervical cancer screening.

BACKGROUND: The indicating FTA card is a dry medium used for collection of cervical samples. HPVIR is a multiplex real-time PCR test that detects 12 high-risk human papillomavirus types (hrHPV) and provides single genotype information for HPV16, - 31, - 35, - 39, - 51, - 56, and - 59 and pooled type information for HPV18/45 and HPV33/52/58. The aim of this study was to evaluate whether a strategy with cervical samples collected on the FTA card and subsequently analysed with the HPVIR test complies with the criteria of the international guidelines for a clinically validated method for cervical screening. METHODS: We performed a non-inferiority test comparing the clinical sensitivity and specificity of the candidate test (FTA card and HPVIR) with a clinically validated reference test (Cobas® HPV test) based on liquid-based cytology (LBC) samples. Two clinical samples (LBC and FTA) were collected from 896 participants in population-based screening. For evaluation of the specificity we used 799 women without ≥ CIN2, and for clinical sensitivity we used 67 women with histologically confirmed ≥ CIN2. The reproducibility was studied by performing inter- and intra-laboratory tests of 558 additional clinical samples. RESULTS: The clinical sensitivity and specificity for samples collected on the FTA card and analysed using the HPVIR test were non-inferior to samples analysed with the Cobas® HPV test based on LBC samples (non-inferiority test score, p = 1.0 × 10- 2 and p = 1.89 × 10- 9, respectively). Adequate agreement of > 87% was seen in both the intra- and inter-laboratory comparisons. CONCLUSIONS: Samples collected on the indicating FTA card and analysed with HPVIR test fulfil the requirements of the international guidelines and can therefore be used in primary cervical cancer screening.

Randomised study of HPV prevalence and detection of CIN2+ in vaginal self-sampling compared to cervical specimens collected by medical personnel.

We conducted a randomised study to compare vaginal self-sampling with assisted sampling by medical personnel on the cervix for HPV testing in primary screening. The first aim was to determine if the HPV prevalence is independent of sampling location (vagina versus cervix) and the person performing the sampling. The second aim was to evaluate if the two sampling strategies differed in the detection rate of CIN2+. In total, 19,523 women were randomised into two groups, with 9926 invited to perform self-sampling (SS arm) using the Rover VIBA-brush and 9597 offered assisted sampling using the cytobrush (AS arm). All samples were applied to the indicating FTA elute card and analysed for high-risk HPV using the hpVIR real-time PCR assay. The outcome for the first aim was HPV prevalence and for the second aim the number of CIN2+ based on histology. In the SS arm, 52.7% of invited women participated in the study, as compared to 34.2% in the AS arm. All samples contained sufficient amount of nuclear DNA for a valid HPV result, with vaginal samples having a higher DNA amount than cervical samples (p < 4.62 × 10-11 ). HPV prevalence was 4.6% in the SS arm and 4.1% in the AS arm (p = 5.5 × 10-2 ), and the distribution of HPV types similar between arms. There was no difference in the prevalence of CIN2+ per 1000 women screened between arms (p = 0.86). The results show that vaginal self-sampling is an equivalent alternative to sampling by medical personnel for HPV typing and identification of CIN2+.

Cervical dysplasia in elderly women performing repeated self-sampling for HPV testing.

BACKGROUND: About 30% of the cervical cancer cases in Sweden occur in women older than 60. The primary aim was to evaluate the acceptability of repeated self-sampling at home for HPV-testing in elderly women. The prevalence of HPV and HPV related dysplasia as well as the sensitivity of cytology was evaluated. METHODS: Repeated self-sampling at home for HPV testing was offered 375 women in each of the four age groups 60, 65, 70 and 75 years. Women with two consecutive positive HPV tests were examined with sampling for histology and cytology. FINDINGS: A self-sample was provided by 59.5% (893/1500) of the invited women. The overall prevalence of HPV was 4.4% (95% CI 3.2-6.0, n = 39) in the first test, and 2.5% were persistent positive in the second test (95% C 1.6-3.8, n = 22) collected on average 5.5 months later. Dysplasia, was found in 1.8% (16/893) (95% CI 1.1-3.0) and CIN 2+ in 1.0% (9/893) (95%CI 0.5-2.0) of the women. Of the 16 women with dysplasia in histology, 13 (81.2%) had a normal cytology. INTERPRETATION: Repeated self-sampling at home combined with HPV testing was well accepted among elderly women. A high prevalence of CIN was diagnosed by histology. Cytology showed extremely low sensitivity and should not be recommended for this age group.

Randomised study shows that repeated self-sampling and HPV test has more than two-fold higher detection rate of women with CIN2+ histology than Pap smear cytology.

This corrects the article DOI: 10.1038/bjc.2017.85.