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.

Data-driven analysis of a validated risk score for ovarian cancer identifies clinically distinct patterns during follow-up and treatment.

Background: Ovarian cancer is the eighth most common cancer among women and due to late detection prognosis is poor with an overall 5-year survival of 30-50%. Novel biomarkers are needed to reduce diagnostic surgery and enable detection of early-stage cancer by population screening. We have previously developed a risk score based on an 11-biomarker plasma protein assay to distinguish benign tumors (cysts) from malignant ovarian cancer in women with adnexal ovarian mass. Methods: Protein concentrations of 11 proteins were characterized in plasma from 1120 clinical samples with a custom version of the proximity extension assay. The performance of the assay was evaluated in terms of prediction accuracy based on receiver operating characteristics (ROC) and multiple hypothesis adjusted Fisher's Exact tests on achieved sensitivity and specificity. Results: The assay's performance is validated in two independent clinical cohorts with a sensitivity of 0.83/0.91 and specificity of 0.88/0.92. We also show that the risk score follows the clinical development and is reduced upon treatment, and increased with relapse and cancer progression. Data-driven modeling of the risk score patterns during a 2-year follow-up after diagnosis identifies four separate risk score trajectories linked to clinical development and survival. A Cox proportional hazard regression analysis of 5-year survival shows that at time of diagnosis the risk score is the second-strongest predictive variable for survival after tumor stage, whereas MUCIN-16 (CA-125) alone is not significantly predictive. Conclusion: The robust performance of the biomarker assay across clinical cohorts and the correlation with clinical development indicates its usefulness both in the diagnostic work-up of women with adnexal ovarian mass and for predicting their clinical course.

Incidence of oncogenic HPV and HPV-related dysplasia five years after a negative HPV test by self-sampling in elderly women.

PURPOSE: Cervical cancer prevention for older women can be challenging since there are no specific guidelines for this group. This study aimed to determine the incidence of oncogenic HPV and HPV-related dysplasia in elderly women 5 years after being HPV negative. METHODS: Invited women participated five years earlier in a study where self-sampling for HPV testing was applied, at this time, they were all HPV negative. The women were now, five years later invited to perform self-sampling for HPV testing. Women with a positive result performed a repeat HPV test. Those with a positive repeat HPV test were examined by colposcopy, biopsy and cytology. RESULTS: Of the 804 invited women, 634 (76.9%) agreed to participate in the study and a self-sampling kit was sent to them. Of these, 99.6% (632/634) sent a sample to the HPV laboratory. The participation rate in each age group was 93.3% at age 65, 74.0% at age 70, 80.7% at age 75 and 64.6% at age 80. Overall 18 women (2.8%, 95% CI 3.2 to 6.0) were HPV positive in the first test and 8 (1.3%, 95% CI 0.6 to 2.6) in the second test. Sampling for the second test was done on average 5.4 months after the first test. Fifty per cent (4/8) of the women with a positive repeat test had dysplasia in histology. CONCLUSION: The incidence of HPV in previously HPV-negative elderly women was low. Among women who were HPV positive in a repeat test, there was a high prevalence of low grade dysplasia.

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.

Identification of Candidate Protein Biomarkers for CIN2+ Lesions from Self-Sampled, Dried Cervico-Vaginal Fluid Using LC-MS/MS.

Molecular screening programs for cervical cancer detect the presence of human papilloma virus (HPV) in cell material or vaginal fluids. Persistent infection with high-risk HPV is a necessary pre-requisite, but the majority of infections do not lead to pathological states. Additional biomarkers are needed to increase the specificity of the molecular tests. Here, we have investigated the possibility of detecting protein biomarkers using mass spectrometry from dried self-sampled cervico-vaginal fluid deposited on FTA cards. We found significant intra-individual correlations (p < 2.2 × 10-16), although heterogenous protein profiles were obtained between individuals. Out of 3699 proteins found in total, 169 were detected in at least 95% of the samples. Using a discovery/replication design, 18 proteins were found to be significant in the discovery cohort, with higher values in those cases compared to controls. All of these were found to also have higher levels among the cases in the replication cohort, with one protein (DEAD-Box Helicase) remaining statistically significant. Finally, a predictive 7-protein multivariate model was developed with a sensitivity and specificity of 0.90 and 0.55, respectively. Our results demonstrate that robust measurements of protein biomarkers can be obtained from self-sampled dried CVF and that these could be used to predict cervical cancer pre-stages.

Temporal changes in the vaginal microbiota in self-samples and its association with persistent HPV16 infection and CIN2.

BACKGROUND: The vaginal microbiota has been reported to be associated with HPV infection and cervical cancer. This study was performed to compare the vaginal microbiota at two timepoints in women performing self-sampling and had a persistent or transient HPV16 infection. The women were tested for 12 high-risk HPV (hrHPV) types but only women with single type (HPV16) were included to reduce confounding variables. METHODS: In total 96 women were included in this study. Of these, 26 were single positive for HPV16 in the baseline test and HPV negative in the follow-up test and 38 were single positive for HPV16 in both tests and diagnosed with CIN2+ in histology. In addition, 32 women that were negative for all 12 HPV tested were included. The samples of vaginal fluid were analyzed with the Ion 16S™ Metagenomics Kit and Ion 16S™ metagenomics module within the Ion Reporter™ software. RESULTS: K-means clustering resulted in two Lactobacillus-dominated groups, one with Lactobacillus sp. and the other specifically with Lactobacillus iners. The two remaining clusters were dominated by a mixed non-Lactobacillus microbiota. HPV negative women had lower prevalence (28%) of the non-Lactobacill dominant cluster in the baseline test, as compared to women with HPV16 infection (42%) (p value = 0.0173). Transition between clusters were more frequent in women with persistent HPV16 infection (34%) as compared in women who cleared the HPV16 infection (19%) (p value = 0.036). CONCLUSIONS: The vaginal microbiota showed a higher rate of transitioning between bacterial profiles in women with persistent HPV16 infection as compared to women with transient infection. This indicate an instability in the microenvironment in women with persistent HPV infection and development of CIN2+.

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.

Daily self-sampling for high-risk human papillomavirus (HR-HPV) testing.

BACKGROUND: Self-sampling for HPV as part of primary screening is a well-tolerated method for women not attending organized Pap smear screening and could increase coverage of cervical cancer screening. OBJECTIVE: To investigate if the prevalence of HR-HPV varies from day to day in infected women and if one single sample is reliable for detecting an ongoing infection. STUDY DESIGN: This is a prospective cohort study on 12 premenopausal and 13 postmenopausal women performing daily self-sampling for HR-HPV testing. They were all HR-HPV-positive 1-3 months ago. Postmenopausal women were sampled for 28 days and premenopausal women sampled during bleeding-free days in one menstrual cycle. A possible difference in viral load between the estrogen-dominated proliferative phase and the progesterone-dominated secretory phase was analyzed. RESULTS AND CONCLUSIONS: Consistent results throughout the sampling period were observed for 19 women, with either a daily presence of HPV (14 women) or no HPV at all during the sampling period (5 women). Of 607 samples from 25 women, 596 were consistently positive or negative for HPV during the sampling period and 11 were inconsistent (2%). There was no difference in HPV copy number between the estrogen dominated proliferative or progesterone dominated secretory menstrual cycle phases. The major finding was a high degree of consistency concerning HR-HPV positivity and negativity of HR-HPV in vaginal fluid during a sustained period of daily self-sampling. It does not appear to matter whether the sample is collected in the proliferative or secretory phase.

Comprehensive profiling of the vaginal microbiome in HIV positive women using massive parallel semiconductor sequencing.

Infections by HIV increase the risk of acquiring secondary viral and bacterial infections and methods are needed to determine the spectrum of co-infections for proper treatment. We used rolling circle amplification (RCA) and Ion Proton sequencing to investigate the vaginal microbiome of 20 HIV positive women from South Africa. A total of 46 different human papillomavirus (HPV) types were found, many of which are not detected by existing genotyping assays. Moreover, the complete genomes of two novel HPV types were determined. Abundance of HPV infections was highly correlated with real-time PCR estimates, indicating that the RCA-Proton method can be used for quantification of individual pathogens. We also identified a large number of other viral, bacterial and parasitic co-infections and the spectrum of these co-infections varied widely between individuals. Our method provides rapid detection of a broad range of pathogens and the ability to reconstruct complete genomes of novel infectious agents.

Reduced expression of TAC1, PENK and SOCS2 in Hcrtr-2 mutated narcoleptic dog brain.

BACKGROUND: Narcolepsy causes dramatic behavioral alterations in both humans and dogs, with excessive sleepiness and cataplexy triggered by emotional stimuli. Deficiencies in the hypocretin system are well established as the origin of the condition; both from studies in humans who lack the hypocretin ligand (HCRT) and in dogs with a mutation in hypocretin receptor 2 (HCRTR2). However, little is known about molecular alterations downstream of the hypocretin signals. RESULTS: By using microarray technology we have screened the expression of 29760 genes in the brains of Doberman dogs with a heritable form of narcolepsy (homozygous for the canarc-1 [HCRTR-2-2] mutation), and their unaffected heterozygous siblings. We identified two neuropeptide precursor molecules, Tachykinin precursor 1 (TAC1) and Proenkephalin (PENK), that together with Suppressor of cytokine signaling 2 (SOCS2), showed reduced expression in narcoleptic brains. The difference was particularly pronounced in the amygdala, where mRNA levels of PENK were 6.2 fold lower in narcoleptic dogs than in heterozygous siblings, and TAC1 and SOCS2 showed 4.4 fold and 2.8 fold decrease in expression, respectively. The results obtained from microarray experiments were confirmed by real-time RT-PCR. Interestingly, it was previously shown that a single dose of amphetamine-like stimulants able to increase wakefulness in the dogs, also produce an increase in the expression of both TAC1 and PENK in mice. CONCLUSION: These results suggest that TAC1, PENK and SOCS2 might be intimately connected with the excessive daytime sleepiness not only in dogs, but also in other species, possibly including humans.

Selection for tameness modulates the expression of heme related genes in silver foxes.

BACKGROUND: The genetic and molecular mechanisms of tameness are largely unknown. A line of silver foxes (Vulpes vulpes) selected for non-aggressive behavior has been used in Russia since the 1960's to study the effect of domestication. We have previously compared descendants of these selected (S) animals with a group of non-selected (NS) silver foxes kept under identical conditions, and showed that changes in the brain transcriptome between the two groups are small. Unexpectedly, many of the genes showing evidence of differential expression between groups were related to hemoproteins. RESULTS: In this study, we use quantitative RT-PCR to demonstrate that the activity of heme related genes differ between S and NS foxes in three regions of the brain. Furthermore, our analyses also indicate that changes in mRNA levels of heme related genes can be well described by an additive polygenic effect. We also show that the difference in genetic background between the two lines of foxes is limited, as estimated by mitochondrial DNA divergence. CONCLUSION: Our results indicate that selection for tameness can modify the expression of heme related genes in canid brain regions known to modulate emotions and behavior. The possible involvement of heme related genes in behavior is surprising. It is possible that hemoglobin modulates the behavior of canids by interaction with CO and NO signaling. Another possibility is that hemorphins, known to be produced after enzymatic cleavage of hemoglobin, are responsible for behavioral alterations. Thus, we hypothesize that hemoglobin metabolism can be a functionally relevant aspect of the domestic phenotype in foxes selected for tameness.

Overview and comparison of ortholog databases.

Orthologs are an indispensable bridge to transfer biological knowledge between species, from protein annotations to sophisticated disease models. However, orthology assignment is not trivial. A large number of resources now exist, each with its own idiosyncrasies. The goal of this review is to compare their contents and clarify which database is most suited for a certain task.:

From wild wolf to domestic dog: gene expression changes in the brain.

Despite the relatively recent divergence time between domestic dogs (Canis familiaris) and gray wolves (Canis lupus), the two species show remarkable behavioral differences. Since dogs and wolves are nearly identical at the level of DNA sequence, we hypothesize that the two species may differ in patterns of gene expression. We compare gene expression patterns in dogs, wolves and a close relative, the coyote (Canis latrans), in three parts of the brain: hypothalamus, amygdala and frontal cortex, with microarray technology. Additionally, we identify genes with region-specific expression patterns in all three species. Among the wild canids, the hypothalamus has a highly conserved expression profile. This contrasts with a marked divergence in domestic dogs. Real-time PCR experiments confirm the altered expression of two neuropeptides, CALCB and NPY. Our results suggest that strong selection on dogs for behavior during domestication may have resulted in modifications of mRNA expression patterns in a few hypothalamic genes with multiple functions. This study indicates that rapid changes in brain gene expression may not be exclusive to the development of human brains. Instead, they may provide a common mechanism for rapid adaptive changes during speciation, particularly in cases that present strong selective pressures on behavioral characters.