Cervical cancer cell supernatants induce a phenotypic switch from U937-derived macrophage-activated M1 state into M2-like suppressor phenotype with change in Toll-like receptor profile

Decoding the immune landscape: a comprehensive analysis of immune-associated biomarkers in cervical carcinoma and their implications for immunotherapy strategies

Background and aims

Cervical cancer, a prevalent gynecological malignant tumor, poses a significant threat to women's health and lives. Immune checkpoint inhibitor (ICI) therapy has emerged as a promising avenue for treating cervical cancer. For patients with persistent or recurrent metastatic cervical cancer, If the sequence of dead receptor ligand-1 (PD-L1) is positive, ICI show significant clinical efficacy. PD-L1 expression serves as a valuable biomarker for assessing ICI therapeutic efficacy. However, the complex tumor immune microenvironment (TIME), encompassing immune cell composition and tumor-infiltrating lymphocyte (TIL) status, also exerts a profound influence on tumor immunity and prognosis. Given the remarkable strides made by ICI treatments in improving the survival rates of cervical cancer patients, it becomes essential to identify a comprehensive biomarker that integrates various TIME aspects to enhance the effectiveness of ICI treatment. Therefore, the quest for biomarkers linked to multiple facets of TIME in cervical cancer is a vital pursuit.

Methods

In this study, we have developed an Immune-Associated Gene Prognostic Index (IRGPI) with remarkable prognostic value specifically for cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC). The Cancer Genome Atlas CESC dataset (n = 305) was meticulously analyzed to pinpoint key immune-related genes via weighted gene co-expression network analysis and differential gene expression assays. Subsequently, we employed Cox regression analysis to construct the IRGPI. Furthermore, the composition of immune cells and TIL status were examined using CIBERSORT and TIDE. Tumor expression of Epigen, LCN10, and P73 were determined with immunohistochemistry.

Results

The resulting IRGPI, composed of EPGN, LCN10, and TP73 genes, displayed a strong negative correlation with patient survival. The discovery was validated with a patient cohort from our hospital. The IRGPI not only predicts the composition of immune cell subtypes such as Macrophages M1, NK cells, Mast cells, Plasma cells, Neutrophils, Dendritic cells, T cells CD8, and T cells CD4 within CESC, but also indicates TIL exclusion, dysfunction, and PD-1 and PD-L1 expression. Therefore, the IRGPI emerges as a promising biomarker not only for prognostic assessment but also for characterizing multiple immune features in CESC. Additionally, our results underscored the significant associations between the IRGPI and immune cell composition, TIL exclusion, and dysfunction, along with PD-1 and PD-L1 expression in the TIME.

Conclusion

Consequently, the IRGPI stands out as a biomarker intimately connected to both the survival and TIME status of CESC patients, offering potential insights into immunotherapy strategies for CESC.

Role of Tumor-Associated Macrophages in Cervical Cancer: Integrating Classical Perspectives with Recent Technological Advances

Tumor-associated macrophages (TAMs) play a pivotal role in the tumor microenvironment, influencing cancer progression and contributing to poor prognosis. However, in cervical cancer (CC), their significance and involvement are relatively less studied than in other gynecological cancers such as ovarian and endometrial cancer. This review aims to provide an overview of TAMs, covering their origins and phenotypes and their impact on CC progression, along with major TAM-targeted therapeutic approaches. Furthermore, we advocate for the integration of cutting-edge research methodologies, such as single-cell RNA sequencing and spatial RNA sequencing, to enable in-depth and comprehensive investigations into TAMs in CC, which would be beneficial in leading to more personalized and effective immunotherapy strategies for patients with CC.

Melatonin modulates L-arginine metabolism in tumor-associated macrophages by targeting arginase 1 in lymphoma

L-Arginine metabolism plays a crucial role in determining the M1/M2 polarization of macrophages. The M1 macrophages express inducible nitric oxide synthase (iNOS), while the M2 macrophages express arginase 1 and metabolize arginine into nitric oxide and urea, respectively. The tumor microenvironment promotes M2 macrophage polarization and consequently switches the metabolic fate of arginine from nitric oxide towards urea production. Importantly, infiltration of M2 macrophages or tumor-associated macrophages (TAMs) has been correlated with poor prognosis of various cancer types. Melatonin is well reported to have antitumor and immunomodulatory properties. However, whether and how it impacts the polarization of TAMs has not been elucidated. Considering the crucial role of arginine metabolism in macrophage polarization, we were interested to know the fate of L-arginine in TAMs and whether it can be reinstated by melatonin or not. We used a murine model of Dalton's lymphoma and established an in vitro model of TAMs. For TAMs, we used the ascitic fluid of tumor-bearing hosts to activate the macrophages in the presence and absence of lipopolysaccharide (LPS). In these groups, L-arginine metabolism was evaluated, and then the effect of melatonin was assessed in these groups, wherein the metabolic fate of arginine as well as the expression of iNOS and arginase 1 were checked. Furthermore, in the in vivo system of the tumor-bearing host, the effect of melatonin was assessed. The in vitro model of TAMs showed a Th2 cytokine profile, reduced phagocytic activity, and increased wound healing ability. Upon investigating arginine metabolism, we observed high urea levels with increased activity and expression of arginase 1 in TAMs. Furthermore, we observed reduced levels of LPS-induced nitric oxide in TAMs; however, their iNOS expression was comparable. With melatonin treatment, urea level decreased significantly, while the reduction in nitric oxide level was not as significant as observed in its absence in TAMs. Also, melatonin significantly reduced arginase activity and expression at the transcriptional and translational levels, while iNOS expression was affected only at the translational level. This effect was further investigated in the in vivo system, wherein melatonin treatment reversed the metabolic fate of arginine, from urea towards nitric oxide, within the tumor microenvironment. This effect was further correlated with pro-apoptotic tumor cell death in the in vivo system. Our results reinforced the immunomodulatory role of melatonin and offered a strong prospect for activating the anti-tumor immune response in cancer conditions.

Tumor microenvironment promotes lymphatic metastasis of cervical cancer: its mechanisms and clinical implications

Although previous studies have shed light on the etiology of cervical cancer, metastasis of advanced cervical cancer remains the main reason for the poor outcome and high cancer-related mortality rate. Cervical cancer cells closely communicate with immune cells recruited to the tumor microenvironment (TME), such as lymphocytes, tumor-associated macrophages, and myeloid-derived suppressor cells. The crosstalk between tumors and immune cells has been clearly shown to foster metastatic dissemination. Therefore, unraveling the mechanisms of tumor metastasis is crucial to develop more effective therapies. In this review, we interpret several characteristics of the TME that promote the lymphatic metastasis of cervical cancer, such as immune suppression and premetastatic niche formation. Furthermore, we summarize the complex interactions between tumor cells and immune cells within the TME, as well as potential therapeutic strategies to target the TME.

Biofilm Potentiates Cancer-Promoting Effects of Tumor-Associated Macrophages in a 3D Multi-Faceted Tumor Model

Components of the tumor microenvironment (TME), such as tumor-associated macrophages (TAMs), influence tumor progression. The specific polarization and phenotypic transition of TAMs in the tumor microenvironment lead to two-pronged impacts that can promote or hinder cancer development and treatment. Here, a novel microfluidic multi-faceted bladder tumor model (TAM^PIEB ) is developed incorporating TAMs and cancer cells to evaluate the impact of bacterial distribution on immunomodulation within the tumor microenvironment in vivo. It is demonstrated for the first time that biofilm-induced inflammatory conditions within tumors promote the transition of macrophages from a pro-inflammatory M1-like to an anti-inflammatory/pro-tumor M2-like state. Consequently, multiple roles and mechanisms by which biofilms promote cancer by inducing pro-tumor phenotypic switch of TAMs are identified, including cancer hallmarks such as reducing susceptibility to apoptosis, enhancing cell viability, and promoting epithelial-mesenchymal transition and metastasis. Furthermore, biofilms formed by extratumoral bacteria can shield tumors from immune attack by TAMs, which can be visualized through various imaging assays in situ. The study sheds light on the underlying mechanism of biofilm-mediated inflammation on tumor progression and provides new insights into combined anti-biofilm therapy and immunotherapy strategies in clinical trials.

Comprehensive analysis of different tumor cell-line produced soluble mediators on the differentiation and functional properties of monocyte-derived dendritic cells

Developing dendritic cells (DCs) from monocytes is a sensitively regulated process. One possible way for cancers to avoid immune recognition and antitumor response is the modulation of DC differentiation. Although several studies are available on the examination of tumor-associated macrophages, a comprehensive analysis focusing on the effects of tumor-formed DCs is not known to date. We provide a comparative analysis of the tumor-edited-monocyte derived DCs differentiated in the presence of adenocarcinomas (MDA, HT29, HeLa)- and primary (WM278, WM983A) or metastatic (WM1617, WM983B) melanomas. The immunomodulatory effect of tumors is mediated at least partly by secreted mediators. We investigated the impact of tumor cell-derived conditioned media on the differentiation of DCs from CD14+ monocytes, sequentially determining the phenotype, cytokine production, phagocytic, and the T cell polarizing capacity of moDCs. We completed our observations by analyzing our data with bioinformatic tools to provide objective correlations between phenotypical and functional properties of different tumor-educated moDCs. The correlation analysis revealed significant differences in the characteristics of adenocarcinomas- or melanomas-edited moDCs. We highlight the functional differences in the properties of moDCs differentiated in the presence of various cancer cell lines. We offer new information and options for the in vitro differentiation protocols of various tumor-conditioned moDCs. Our results confirm that various immunomodulatory properties of different tumor cell lines result in multiple manipulations of DC differentiation.

Cervical Cancer Outcome and Tumor-Associated Macrophages: Research Evidence

Inflammation is a key factor in cancer promotion. Tumor-associated macrophages (TAMs), as part of the tumor microenvironment, are often associated with the progression of tumors and a worse prognosis in many cancers, namely on cervical cancer. This work exhaustively summarizes the conclusions of the different studies published concerning TAMs function in cervical cancer, from in vitro studies using cancer cell lines to the clinical perspective (histological samples-based studies). Most studies have led to the conclusion that TAMs increased density is directly related to increased severity of a malignant cervical lesion. Additionally, TAMs are normally polarized into an M2 phenotype, benefiting and promoting tumor progression, resulting in a worse disease outcome. The tumor microenvironment is also a highly critical contributor that not only influences tumor natural history but also modulates the specific immune response.

Cervical Cancer: Emerging Immune Landscape and Treatment

Immune cells are essential for defending the body’s balance and have increasingly been implicated in controlling tumor growth. In cervical cancer (CC), the immune landscape is extensively connected with human papillomavirus (HPV) status. Recent insights from studies have revealed that as a result of infection with HPV, immune cell populations such as lymphocytes or monocytes change during carcinogenesis. Immune therapy, in particular checkpoint inhibitors, those targeting PD-1 or PD-L1, has shown promising efficacy. This article reviews the immune landscape and immunotherapy of CC.

The Formation and Therapeutic Update of Tumor-Associated Macrophages in Cervical Cancer

Both clinicopathological and experimental studies have suggested that tumor-associated macrophages (TAMs) play a key role in cervical cancer progression and are associated with poor prognosis in the respects of tumor cell proliferation, invasion, angiogenesis, and immunosuppression. Therefore, having a clear understanding of TAMs is essential in treating this disease. In this review, we will discuss the origins and categories of macrophages, the molecules responsible for forming and reeducating TAMs in cervical cancer (CC), the biomarkers of macrophages and the therapy development targeting TAMs in CC research.

The supernatant of cervical carcinoma cells lines induces a decrease in phosphorylation of STAT-1 and NF-κB transcription factors associated with changes in profiles of cytokines and growth factors in macrophages derived from U937 cells

Macrophages are presents in the tumor microenvironment and acquire different phenotypic and functional characteristics in response to microenvironmental signals. Macrophages can be differentiated into two phenotypes: M1 or pro-inflammatory (classically activated), and M2 or anti-inflammatory macrophage (alternatively activated). In response to the microenvironment, macrophages activate transcription factors as STAT1 and NF-κB-p65 for M1 macrophages or STAT3 and STAT6 for M2 macrophages; activation impacts on the profile of cytokine, chemokines and growth factors secreted by macrophages. We evaluated the effect of the supernatant of cervical-derived carcinoma cell lines HeLa, SiHa, and C-33A on the phosphorylation of transcriptional factors STAT1, NF-κB-p65, and STAT6, and their impact in the profile of secretion of cytokines and growth factors by macrophages derived from the U937 cell line. The results show that in macrophages, these supernatants induce a decrease in the phosphorylation of NF-κB-p65 and STAT1 in U937-macrophages accompanied by an increase in the secretion of IL-10, IL-6, MCP-1, and IL-8, as well as GM-CSF, G-CSF, PDGF-AA, PDGF-BB, and VEGF. Our results suggest that HeLa, SiHa, and C-33A cell lines down-regulate the activation of transcription factors characteristic of M1 macrophages (STAT1, NF-κB-p65) and induce the secretion of factors that favor tumor growth.

Melatonin and inflammation-Story of a double-edged blade

Melatonin is an immune modulator that displays both pro- and anti-inflammatory properties. Proinflammatory actions, which are well documented by many studies in isolated cells or leukocyte-derived cell lines, can be assumed to enhance the resistance against pathogens. However, they can be detrimental in autoimmune diseases. Anti-inflammatory actions are of particular medicinal interest, because they are observed in high-grade inflammation such as sepsis, ischemia/reperfusion, and brain injury, and also in low-grade inflammation during aging and in neurodegenerative diseases. The mechanisms contributing to anti-inflammatory effects are manifold and comprise various pathways of secondary signaling. These include numerous antioxidant effects, downregulation of inducible and inhibition of neuronal NO synthases, downregulation of cyclooxygenase-2, inhibition of high-mobility group box-1 signaling and toll-like receptor-4 activation, prevention of inflammasome NLRP3 activation, inhibition of NF-κB activation and upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2). These effects are also reflected by downregulation of proinflammatory and upregulation of anti-inflammatory cytokines. Proinflammatory actions of amyloid-β peptides are reduced by enhancing α-secretase and inhibition of β- and γ-secretases. A particular role in melatonin's actions seems to be associated with the upregulation of sirtuin-1 (SIRT1), which shares various effects known from melatonin and additionally interferes with the signaling by the mechanistic target of rapamycin (mTOR) and Notch, and reduces the expression of the proinflammatory lncRNA-CCL2. The conclusion on a partial mediation by SIRT1 is supported by repeatedly observed inhibitions of melatonin effects by sirtuin inhibitors or knockdown.

Melanoma exosomes promote mixed M1 and M2 macrophage polarization

Macrophages are key participants in melanoma growth and survival. In general, macrophages can be classified as M1 or M2 activation phenotypes. Increasing evidence demonstrates that melanoma exosomes also facilitate tumor survival and metastasis. However, the role of melanoma exosomes in directly influencing macrophage function is poorly understood. Herein, we investigated the hypothesis that natural melanoma exosomes might directly influence macrophage polarization. To explore this hypothesis, ELISA, RT-qPCR, and macrophage functional studies were performed in vitro using an established source of melanoma exosomes (B16-F10). ELISA results for melanoma exosome induction of common M1 and M2 cytokines in RAW 264.7 macrophages, revealed that melanoma exosomes do not polarize macrophages exclusively in the M1 or M2 direction. Melanoma exosomes induced the M1 and M2 representative cytokines TNF-α and IL-10 respectively. Further assessment, using an RT-qPCR array with RAW 264.7 and primary macrophages, confirmed and extended the ELISA findings. Upregulation of markers common to both M1 and M2 polarization phenotypes included CCL22, IL-12B, IL-1β, IL-6, i-NOS, and TNF-α. The M2 cytokine TGF-β was upregulated in primary but not RAW 264.7 macrophages. Pro-tumor functions have been attributed to each of these markers. Macrophage functional assays demonstrated a trend toward increased i-NOS (M1) to arginase (M2) activity. Collectively, the results provide the first evidence that melanoma exosomes can induce a mixed M1 and M2 pro-tumor macrophage activation phenotype.

Correlation of Circulating CD64+/CD163+ Monocyte Ratio and stroma/peri-tumoral CD163+ Monocyte Density with Human Papillomavirus Infected Cervical Lesion Severity

HPV infected cervical cells secrete mediators that are gradually changed and have influence on infiltrating M2 phenotypic monocytes in cervical lesions. However, profiles of circulating immune cells in women with cervical lesions and M2 phenotypic monocyte activity in HPV infected cervical lesions are limited. This study aimed to investigate circulating monocyte populations correlated with M2 phenotype density and its activity in HPV infected cervical lesions. HPV DNA was investigated in cervical tissues using PCR. High risk HPV E6/E7 mRNA was detected using in situ hybridization. CD163 immunohistochemical staining was performed for M2 macrophage. CD163 and Arg1 mRNA expression were detected using real-time PCR. Circulating monocyte subpopulations were analyzed using flow cytometry. CD163 and Arg1 mRNA expression were increased according to cervical lesion severity and corresponding with density of M2 macrophage in HSIL and SCC in stroma and peri-tumoral areas. Additionally, the relationship between M2 macrophage infiltration and high risk HPV E6/E7 mRNA expression was found and corresponded with cervical lesion severity. Circulating CD14⁺CD16⁺ and CD14⁺CD163⁺ monocytes were elevated in No-SIL and cervical lesions. Interestingly, CD14⁺CD64⁺ monocyte was greatly elevated in HSIL and SCC, whereas intracellular IL-10⁺ monocytes were not significantly different between cervical lesions. The correlation between increasing ratio of circulating CD64⁺/CD163⁺ monocyte and density of infiltrating CD163⁺ monocytes was associated with severity of HPV infected cervical lesions. The elevated circulating CD64⁺/CD163⁺ monocyte ratio correlates to severity of HPV infected cervical lesions and might be a prognostic marker in cervical cancer progression.

Classical and non-classical HLA class I aberrations in primary cervical squamous- and adenocarcinomas and paired lymph node metastases

Background

Tumors avoid destruction by cytotoxic T cells (CTL) and natural killer (NK) cells by downregulation of classical human leukocyte antigens (HLA) and overexpression of non-classical HLA. This is the first study to investigate HLA expression in relation to histology (squamous cell carcinoma (SCC) vs. adenocarcinoma (AC)), clinicopathological parameters and survival in a large cervical cancer patient cohort.

Methods

Classical (HLA-A and HLA-B/C)- and non-classical HLA molecules (HLA-E and HLA-G) were studied on primary tumors and paired lymph node (LN) metastases from cervical cancer patients (n = 136) by immunohistochemistry. The Chi² test was used for the comparison of clinicopathological characteristics between SCC and AC patients. The Related-Samples Wilcoxon Signed Rank test was used to compare HLA expression between the primary tumor and metastasis in LN. Patient survival rates were analyzed by Kaplan-Meier curves and Log Rank test. The Mann-Whitney U Test was used to compare the distribution of HLA class I expression between SCC and AC.

Results

Decreased expression of HLA-A (SCC P < 0.001), HLA-B/C (SCC P < 0.01; AC P < 0.01) and total classical HLA (SCC P < 0.001; AC P = 0.02) was apparent in metastatic tumor cells compared to the primary tumor. In primary SCC, there was a clear trend towards complete loss of HLA-A (P = 0.05). SCC metastases showed more complete loss of HLA-A, while AC metastases showed more complete loss of HLA-B/C (P = 0.04). In addition, tumor size and parametrium involvement were also related to aberrant HLA class I expression. No significant associations between HLA expression and disease-specific (DSS) or disease-free survival (DFS) were found in this advanced disease cohort. However, in the SCC group, samples showing loss of HLA-A or loss of total classical HLA but positive for HLA-G were linked to poor patient survival (DSS P = 0.001 and P = 0.01; DFS P = 0.003 and P = 0.01, for HLA-A and total classical HLA, respectively).

Conclusion

These results strengthen the idea of tumor immune escape variants leading to metastasis. Moreover, SCC tumors showing downregulation of HLA-A or total classical HLA in combination with HLA-G expression had poor prognosis. Our findings warrant further analysis of HLA expression as a biomarker for patient selection for CTL- and NK- cell based immunotherapeutic intervention.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-016-0184-3) contains supplementary material, which is available to authorized users.

A cancer treatment based on synergy between anti-angiogenic and immune cell therapies

A mathematical model integrating tumor angiogenesis and tumor-targeted cytotoxicity by immune cells was developed to identify the therapeutic window of two distinct modes to treat cancer: (1) an anti-angiogenesis treatment based on the monoclonal antibody bevacizumab that targets tumor vasculature, and (2) immunotherapy involving the injection of unlicensed dendritic cells to boost the anti-tumor adaptive response. The angiogenic cytokine Vascular Endothelial Growth Factor (VEGF) contributes to the immunosuppressive tumor microenvironment, which is responsible for the short-lived therapeutic effect of cancer-targeted immunotherapy. The effect of immunosuppression on the width of the therapeutic window of each treatment was quantified. Experimental evidence has shown that neutralizing immunosuppressive cytokines results in an enhanced immune response against infections and chronic diseases. The model was used to determine treatment protocols involving the combination of anti-VEGF and unlicensed dendritic cell injections that enhance tumor regression. The model simulations predicted that the most effective method to treat tumors involves administering a series of biweekly anti-VEGF injections to disrupt angiogenic processes and limit tumor growth. The simulations also verified the hypothesis that reducing the concentration of the immunosuppressive factor VEGF prior to an injection of unlicensed dendritic cells enhances the cytotoxicity of CD8+ T cells and results in complete tumor elimination. Feasible treatment protocols for tumors that are diagnosed late and have grown to a relatively large size were identified.

Cathepsin D: an Mϕ-derived factor mediating increased endothelial cell permeability with implications for alteration of the blood-retinal barrier in diabetic retinopathy

Inflammation plays an important role in the pathogenesis of diabetic retinopathy (DR). We have previously reported increased monocyte (Mono) trafficking into the retinas of diabetic animals. In this study, we have examined the effect of activated Monos on retinal endothelial cells (ECs). The U937 Mϕ-conditioned medium (CM) significantly decreased the transendothelial resistance of EC monolayers as measured by electric cell-substrate impedance sensing (P= 0.007). The CM was fractioned, and the effective fraction (30-100 kDa) was analyzed by liquid chromatography-mass spectrometry, and cathepsin D (CD) was identified as a major secreted product. Immunoprecipitated CD resulted in decreased resistance in ECs (P= 0.006). The specificity of CD in mediating alterations of the EC barrier was confirmed using small interfering RNA. The decreased resistance correlated with a significantly increased gap between ECs. CD altered the Ras homolog gene family, member A/Rho-associated kinase pathway with increased stress actin filament formation in the EC layer. Increased CD levels were found in the retinas of diabetic mice (3-fold) and serum samples of patients with diabetic macular edema (1.6-fold) measured by Western blot and ELISA. These findings suggest an important role for Mϕ-derived CD in altering the blood-retinal barrier and reveal a potential therapeutic target in the treatment of DR.-Monickaraj, F., McGuire, P. G., Nitta, C. F., Ghosh, K., Das, A. Cathepsin D: an Mϕ-derived factor mediating increased endothelial cell permeability with implications for alteration of the blood-retinal barrier in diabetic retinopathy.

A clinicopathological study of episomal papillomavirus infection of the human placenta and pregnancy complications

Viral infections are known to adversely affect pregnancy, but scant attention has been given to human papilloma virus (HPV) infection. We aimed to determine the molecular and histopathological features of placental HPV infection, in association with pregnancy complications including fetal growth restriction, pre-maturity, pre-eclampsia, and diabetes. Three hundred and thirty-nine placentae were selected based on the presence or absence of pregnancy complications. Five independent methods were used to identify HPV in the placenta, namely, immunohistochemistry for L1 viral capsid, in situ hybridization to high-risk HPV DNA, PCR, western blotting, and transmission electron microscopy. Pregnancy complications and uterine cervical smear screening results were correlated with placental HPV histopathology. In this study, which was deliberately biased towards complications, HPV was found in the decidua of 75% of placentae (253/339) and was statistically associated with histological acute chorioamnionitis (P<0.05). In 14% (35/253) of the HPV positive cases, HPV L1 immunoreactivity also occurred in the villous trophoblast where it was associated with a lymphohistiocytic villitis (HPV-LHV), and was exclusively of high-risk HPV type. HPV-LHV significantly associated with fetal growth restriction, preterm delivery, and pre-eclampsia (all P<0.05). All cases of pre-eclampsia (20/20) in our cohort had high-risk placental HPV. A further 55 cases (22%, 55/253) of HPV positive placentae had minimal villous trophoblast HPV L1 immunoreactivity, but a sclerosing pauci-immune villitis, statistically associated with diabetes (49.1%, 27/55, P<0.05). For women with placental HPV, 33% (69/207) had an HPV-related positive smear result before pregnancy compared with (9.4% 8/85) of women with HPV-negative placentae (P=0.0001). Our findings support further investigations to determine if vaccination of women and men will improve pregnancy outcomes.