Comparison of the basal and glucocorticoid-inducible activities of the upstream regulatory regions of HPV18 and HPV31 in multiple epithelial cell lines

The Interaction of Human Papillomavirus Infection and Prostaglandin E2 Signaling in Carcinogenesis: A Focus on Cervical Cancer Therapeutics

Chronic infection by high-risk human papillomaviruses (HPV) and chronic inflammation are factors associated with the onset and progression of several neoplasias, including cervical cancer. Oncogenic proteins E5, E6, and E7 from HPV are the main drivers of cervical carcinogenesis. In the present article, we review the general mechanisms of HPV-driven cervical carcinogenesis, as well as the involvement of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) and downstream effectors in this pathology. We also review the evidence on the crosstalk between chronic HPV infection and PGE2 signaling, leading to immune response weakening and cervical cancer development. Finally, the last section updates the current therapeutic and preventive options targeting PGE2-derived inflammation and HPV infection in cervical cancer. These treatments include nonsteroidal anti-inflammatory drugs, prophylactic and therapeutical vaccines, immunomodulators, antivirals, and nanotechnology. Inflammatory signaling pathways are closely related to the carcinogenic nature of the virus, highlighting inflammation as a co-factor for HPV-dependent carcinogenesis. Therefore, blocking inflammatory signaling pathways, modulating immune response against HPV, and targeting the virus represent excellent options for anti-tumoral therapies in cervical cancer.

Naturally Occurring Variations Modulate the Activity of the HPV33 Early Promoter and its Affinity for the E2 Transcription Factor

The human papillomavirus (HPV) Long Control Region (LCR) encompasses the early promoter (EP) that drives transcription of the E6 and E7 oncogenes in keratinocytes and HPV-associated cancers. In this study, the transcriptional activities of the HPV33 EP from the prototype LCR and from eight variants representative of the worldwide diversity of the virus were examined in primary human keratinocytes (PHK) and in the HeLa cervical carcinoma cell line by luciferase reporter-gene assays. Remarkably, the two variations with the greatest effect on the EP in PHK were C7732G and a 79-bp deletion that were associated with high-grade cervical lesions and persistent infections, respectively, in epidemiological studies. In contrast, the three variations most active in HeLa cells were C7537A, A7874C and A7879G. A7874C, which lies within an E2-binding sequence, is also shown to increase the activity and binding of E2 at this site. Collectively, these results indicate that naturally-occurring variations affect the HPV33 EP differentially in PHK than in cancer cells and, furthermore, that they can also alter its regulation by E2. These findings provide a molecular basis for rationalizing the results of previous epidemiological studies and for understanding the contribution of LCR polymorphisms to the oncogenicity and persistence of HPV33 infections.

Detection of human papillomavirus-16 DNA in archived clinical samples of breast and lung cancer patients from North Pakistan

PURPOSE

Over the past few decades, human papillomavirus (HPV) has been recorded as a key player in the development of various genital cancers, most notably cervical cancer. It has also been associated with some non-genital cancers. A subset of oropharyngeal cancers are known to be caused by HPV. Its aetiological involvement has been suggested for breast and lung cancer as well. However, reports regarding the HPV DNA detection vary widely from different parts of the world. Due to scarcity of local data in this regard, the current study aimed at retrospective detection of HPV presence in the archival samples of breast and lung cancer patients from north part of the country.

METHODS

A total of 55 formalin-fixed paraffin-embedded tissue sections of invasive ductal carcinoma of breast (n = 46) and lung (n = 9) were collected for this study. Genotyping for HPV16 and 18 was carried out through PCR.

RESULTS

HPV16 DNA was found in both breast and lung carcinoma samples with the prevalence rate of 17 and 11 %, respectively. An interesting association was found between ER/PR (Oestrogen/Progesterone receptor) and HER2/Neu (Human epidermal growth factor receptor-2) positivity with HPV occurrence in breast tumours.

CONCLUSION

Current study shows the presence of HPV16 DNA in archived clinical biopsy sections from breast and lung cancers (17, 11 %), respectively. A positive correlation of HPV16 presence was found with ER/PR and HER2-positive breast cancers. These initial findings warrant further investigation in order to determine HPV prevalence and aetiological role in local cancers, especially in ER/PR/HER2-positive breast cancers on a larger scale.

Human Papilloma Virus Identification in Breast Cancer Patients with Previous Cervical Neoplasia

Purpose

Women with human papilloma virus (HPV)-associated cervical neoplasia have a higher risk of developing breast cancer than the general female population. The purpose of this study was to (i) identify high-risk HPVs in cervical neoplasia and subsequent HPV positive breast cancers which developed in the same patients and (ii) determine if these HPVs were biologically active.

Methods

A range of polymerase chain reaction and immunohistochemical techniques were used to conduct a retrospective cohort study of cervical precancers and subsequent breast cancers in the same patients.

Results

The same high-risk HPV types were identified in both the cervical and breast specimens in 13 (46%) of 28 patients. HPV type 18 was the most prevalent. HPVs appeared to be biologically active as demonstrated by the expression of HPV E7 proteins and the presence of HPV-associated koilocytes. The average age of these patients diagnosed with breast cancer following prior cervical precancer was 51 years, as compared to 60 years for all women with breast cancer (p for difference = 0.001).

Conclusion

These findings indicate that high-risk HPVs can be associated with cervical neoplasia and subsequent young age breast cancer. However, these associations are unusual and are a very small proportion of breast cancers. These outcomes confirm and extend the observations of two similar previous studies and offer one explanation for the increased prevalence of serious invasive breast cancer among young women.

Human Papilloma Viruses and Breast Cancer

PURPOSE

Human papillomaviruses (HPV) may have a role in some breast cancers. The purpose of this study is to fill important gaps in the evidence. These gaps are: (i) confirmation of the presence of high risk for cancer HPVs in breast cancers, (ii) evidence of HPV infections in benign breast tissues prior to the development of HPV-positive breast cancer in the same patients, (iii) evidence that HPVs are biologically active and not harmless passengers in breast cancer.

METHODS

RNA-seq data from The Cancer Genome Atlas (TCGA) was used to identify HPV RNA sequences in breast cancers. We also conducted a retrospective cohort study based on polymerase chain reaction (PCR) analyses to identify HPVs in archival specimens from Australian women with benign breast biopsies who later developed breast cancer. To assess whether HPVs in breast cancer were biologically active, the expression of the oncogenic protein HPV E7 was assessed by immunohistochemistry (IHC).

RESULTS

Thirty (3.5%) low-risk and 20 (2.3%) high-risk HPV types were identified in 855 breast cancers from the TCGA database. The high risk types were HPV 18 (48%), HPV 113 (24%), HPV 16 (10%), HPV 52 (10%). Data from the PCR cohort study indicated that HPV type 18 was the most common type identified in breast cancer specimens (55% of 40 breast cancer specimens) followed by HPV 16 (13%). The same HPV type was identified in both the benign and subsequent breast cancer in 15 patients. HPV E7 proteins were identified in 72% of benign breast specimens and 59% of invasive breast cancer specimens.

CONCLUSION

There were four observations of particular interest: (i) confirmation by both NGS and PCR of the presence of high-risk HPV gene sequences in breast cancers, (ii) a correlation between high-risk HPV in benign breast specimens and subsequent HPV-positive breast cancer in the same patient, (iii) HPVs in breast cancer are likely to be biologically active (as shown by transcription of HPV DNA to RNA plus the expression of HPV E7 proteins), (iv) HPV oncogenic influences may occur early in the development of breast cancer.

Glucocorticoid regulation of a novel HPV-E6-p53-miR-145 pathway modulates invasion and therapy resistance of cervical cancer cells

Glucocorticoids are stress-responsive neuroendocrine mediators and play an important role in malignant progression, especially in solid tumours. We demonstrate a novel mechanism by which glucocorticoids modulate p53-dependent miR-145 expression in HPV-positive cervical cancer cells through induction of E6 proteins. We found that expression of miR-145 was reduced in cervical cancer tissues. Cortisol induced HPV-E6 expression and suppressed p53 and miR-145 in cervical cancer cells. MiR-145 expression in cervical cancer cells was wild-type p53-dependent, and cortisol-induced down-regulation of miR-145 expression prevented chemotherapy-induced apoptosis, whereas over-expression of miR-145 enhanced sensitivity to mitomycin and reversed the chemoresistance induced by glucocorticoids. We also show that miR-145 augments the effects of p53 by suppressing the inhibitors of p53 in cervical cancer cells, suggesting that miR-145 plays a role in p53 tumour suppression. Finally, we demonstrate that miR-145 inhibits both the motility and invasion of cervical cancer cells. Our findings identify a novel pathway through which the neuroendocrine macroenvironment affects cervical tumour growth, invasion and therapy resistance and show that miR-145 may serve as a target for cervical cancer therapy. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Stress management effects on perceived stress and cervical neoplasia in low-income HIV-infected women

OBJECTIVE

Risk for developing cervical neoplastic disease is greatly increased in women infected with oncogenic sexually transmitted human papillomaviruses (HPVs) and who have lowered cellular immunity due to coinfection with human immunodeficiency virus (HIV) infection. The majority of these individuals are low-income minority women. Factors associated with promotion of HPV to cervical neoplasia in HIV-infected populations include degree of immunosuppression as well as behavioral factors such as tobacco smoking and psychological stress. This study examined the effects of a cognitive behavioral stress management (CBSM) intervention on life stress and cervical neoplasia in HIV+ minority women.

METHODS

Participants were 39 HIV+ African-American, Caribbean, and Hispanic women with a recent history of an abnormal Papanicolaou smear. Participants underwent colposcopic examination, psychosocial interview, and peripheral venous blood draw at study entry and 9 months after being randomly assigned to either a 10-week CBSM group intervention (n=21) or a 1-day CBSM workshop (n=18).

RESULTS

Women assigned to the 10-week group-based CBSM intervention reported decreased perceived life stress and had significantly lower odds of cervical neoplasia over a 9-month follow-up. CBSM effects on life stress and neoplasia appeared independent of presence of neoplasia at study entry, HPV type, CD4+CD3+ cell count, HIV viral load, and substance use. Furthermore, CBSM intervention effects on cervical neoplasia were especially pronounced among women with residual life stress at follow-up.

CONCLUSION

These findings suggest that stress management decreases perceived life stress and may decrease the odds of cervical neoplasia in women with HIV and a history of abnormal Papanicolaou smears. Although preliminary, these findings suggest the utility of stress management as a cancer prevention strategy in this high-risk population.

Exploring the relation between human papilloma virus and larynx cancer

Human papilloma virus (HPV) has a role in benign and malignant pathology of the larynx. In this review we present the biological and epidemiological aspects related to these issues.

The oncogenic potential of human papillomaviruses: a review on the role of host genetics and environmental cofactors

Human papillomaviruses (HPVs), with over 100 genotypes, are a very complex group of human pathogenic viruses. In most cases, HPV infection results in benign epithelial proliferations (verrucae). However, oncogenic types of HPV may induce malignant transformation in the presence of cofactors. For example, over 99% of all cervical cancers and a majority of vulval, vaginal, anal and penile cancers are the result of oncogenic HPV types. Such HPV types have been increasingly linked to other epithelial cancers involving the skin, larynx and oesophagus. Although viral infection is necessary for neoplastic transformation, evidence suggests that host and environmental cofactors are also required. Research investigating HPV oncogenesis is complex and quite extensive. The inability to produce mature HPV virions in animal models has been a major limitation in fully elucidating the oncogenic potential and role of associated cofactors in promoting malignant transformation in HPV-infected cells. We have reviewed the literature and provide a brief account of the current understanding of HPV oncogenesis, emphasizing the role of genetic susceptibility, immune response, and environmental and infectious cofactors.

The influence of bio-behavioural factors on tumour biology: pathways and mechanisms

Epidemiological studies indicate that stress, chronic depression and lack of social support might serve as risk factors for cancer development and progression. Recent cellular and molecular studies have identified biological processes that could potentially mediate such effects. This review integrates clinical, cellular and molecular studies to provide a mechanistic understanding of the interface between biological and behavioural influences in cancer, and identifies novel behavioural or pharmacological interventions that might help improve cancer outcomes.

Genetic analysis of the human papillomavirus type 31 differentiation-dependent late promoter

Human papillomaviruses infect stratifying squamous epithelia, causing benign and malignant lesions. Upon differentiation of the host keratinocyte, the virus undergoes a dramatic increase in both DNA replication and transcription from the late promoter, leading to expression of late genes and virion morphogenesis. In human papillomavirus type 31 (HPV31), the late promoter is designated p742 and includes multiple start sites embedded within the E7 gene. In this report, we mapped viral DNA elements that control transcriptional activity from p742. Enhancer elements in the viral upstream regulatory region positively regulate this promoter. The region containing the transcriptional start sites is dispensable for activity, and at least two separate elements in the E6/E7 region are capable of supporting transcription. Of these, we mapped one to a 150-bp region of the E7 open reading frame and designate it the core p742 promoter. Using GF109203X, an inhibitor of protein kinase C signaling, we show that p742 activation is independent of viral genome amplification. Finally, we mapped elements in the region of p742 that confer responsiveness to differentiation and show that the upstream regulatory region does not contribute to the differentiation response of p742. These studies are an important step toward understanding the functioning and regulation of this multiple-start promoter.

Propagation, infection, and neutralization of authentic HPV16 virus

Despite the prevalence of HPV16 in invasive cervical cancers, an in vitro system capable of producing infectious HPV16 is lacking. The organotypic (raft) culture system has allowed for the study of the entire differentiation-dependent life cycle of human papillomaviruses (HPVs). However, the use of this system with the prototype HPV16-containing cell line, W12, has failed to yield infectious virus. Our laboratory has introduced clinically derived HPV16(114/B) genomic DNA into primary keratinocytes, where it subsequently recircularized and maintained episomally at 50-100 copies per cell. Virion morphogenesis occurred after epithelial stratification and differentiation in raft culture. HPV16 virions were isolated that were able to infect keratinocytes in vitro. Infection was neutralized by monoclonal antibodies raised against HPV16 but not by monoclonal antibodies known to neutralize other HPV types.