Patient-Derived Xenograft Models for Ovarian Cancer

Patient-derived xenograft (PDX) models play a crucial role for in vivo research. They maintain the original molecular characteristics of the human tumor and provide a more accurate tumor microenvironment, which cannot be replicated by in vitro models. This chapter describes four different transplantation methods, namely, intra-bursal, intrarenal capsule, intraperitoneal, and subcutaneous, to develop PDX models for ovarian cancer research.

The microtubule inhibitor eribulin demonstrates efficacy in platinum-resistant and refractory high-grade serous ovarian cancer patient-derived xenograft models

Background

Despite initial response to platinum-based chemotherapy and PARP inhibitor therapy (PARPi), nearly all recurrent high-grade serous ovarian cancer (HGSC) will acquire lethal drug resistance; indeed, ~15% of individuals have de novo platinum-refractory disease.

Objectives

To determine the potential of anti-microtubule agent (AMA) therapy (paclitaxel, vinorelbine and eribulin) in platinum-resistant or refractory (PRR) HGSC by assessing response in patient-derived xenograft (PDX) models of HGSC.

Design and methods

Of 13 PRR HGSC PDX, six were primary PRR, derived from chemotherapy-naïve samples (one was BRCA2 mutant) and seven were from samples obtained following chemotherapy treatment in the clinic (five were mutant for either BRCA1 or BRCA2 (BRCA1/2), four with prior PARPi exposure), recapitulating the population of individuals with aggressive treatment-resistant HGSC in the clinic. Molecular analyses and in vivo treatment studies were undertaken.

Results

Seven out of thirteen PRR PDX (54%) were sensitive to treatment with the AMA, eribulin (time to progressive disease (PD) ⩾100 days from the start of treatment) and 11 out of 13 PDX (85%) derived significant benefit from eribulin [time to harvest (TTH) for each PDX with p < 0.002]. In 5 out of 10 platinum-refractory HGSC PDX (50%) and one out of three platinum-resistant PDX (33%), eribulin was more efficacious than was cisplatin, with longer time to PD and significantly extended TTH (each PDX p < 0.02). Furthermore, four of these models were extremely sensitive to all three AMA tested, maintaining response until the end of the experiment (120d post-treatment start). Despite harbouring secondary BRCA2 mutations, two BRCA2-mutant PDX models derived from heavily pre-treated individuals were sensitive to AMA. PRR HGSC PDX models showing greater sensitivity to AMA had high proliferative indices and oncogene expression. Two PDX models, both with prior chemotherapy and/or PARPi exposure, were refractory to all AMA, one of which harboured the SLC25A40-ABCB1 fusion, known to upregulate drug efflux via MDR1.

Conclusion

The efficacy observed for eribulin in PRR HGSC PDX was similar to that observed for paclitaxel, which transformed ovarian cancer clinical practice. Eribulin is therefore worthy of further consideration in clinical trials, particularly in ovarian carcinoma with early failure of carboplatin/paclitaxel chemotherapy.

NETosis as an oncologic therapeutic target: a mini review

Neutrophil Extracellular Traps (NETs) are a key form of pro-inflammatory cell death of neutrophils characterized by the extrusion of extracellular webs of DNA containing bactericidal killing enzymes. NETosis is heavily implicated as a key driver of host damage in autoimmune diseases where injurious release of proinflammatory enzymes damage surrounding tissue and releases 70 known autoantigens. Recent evidence shows that both neutrophils and NETosis have a role to play in carcinogenesis, both indirectly through triggering DNA damage through inflammation, and directly contributing to a pro-tumorigenic tumor microenvironment. In this mini-review, we summarize the current knowledge of the various mechanisms of interaction and influence between neutrophils, with particular attention to NETosis, and cancer cells. We will also highlight the potential avenues thus far explored where we can intercept these processes, with the aim of identifying promising prospective targets in cancer treatment to be explored in further studies.

Epithelial-to-Mesenchymal Transition Supports Ovarian Carcinosarcoma Tumorigenesis and Confers Sensitivity to Microtubule Targeting with Eribulin

Ovarian carcinosarcoma (OCS) is an aggressive and rare tumor type with limited treatment options. OCS is hypothesized to develop via the combination theory, with a single progenitor resulting in carcinomatous and sarcomatous components, or alternatively via the conversion theory, with the sarcomatous component developing from the carcinomatous component through epithelial-to-mesenchymal transition (EMT). In this study, we analyzed DNA variants from isolated carcinoma and sarcoma components to show that OCS from 18 women is monoclonal. RNA sequencing indicated that the carcinoma components were more mesenchymal when compared with pure epithelial ovarian carcinomas, supporting the conversion theory and suggesting that EMT is important in the formation of these tumors. Preclinical OCS models were used to test the efficacy of microtubule-targeting drugs, including eribulin, which has previously been shown to reverse EMT characteristics in breast cancers and induce differentiation in sarcomas. Vinorelbine and eribulin more effectively inhibited OCS growth than standard-of-care platinum-based chemotherapy, and treatment with eribulin reduced mesenchymal characteristics and N-MYC expression in OCS patient-derived xenografts. Eribulin treatment resulted in an accumulation of intracellular cholesterol in OCS cells, which triggered a downregulation of the mevalonate pathway and prevented further cholesterol biosynthesis. Finally, eribulin increased expression of genes related to immune activation and increased the intratumoral accumulation of CD8+ T cells, supporting exploration of immunotherapy combinations in the clinic. Together, these data indicate that EMT plays a key role in OCS tumorigenesis and support the conversion theory for OCS histogenesis. Targeting EMT using eribulin could help improve OCS patient outcomes.

SIGNIFICANCE

Genomic analyses and preclinical models of ovarian carcinosarcoma support the conversion theory for disease development and indicate that microtubule inhibitors could be used to suppress EMT and stimulate antitumor immunity.

Hedgehog inhibition impaired platinum response in high-grade serous ovarian cancer harboring high hedgehog ligand expression and mTOR pathway activation

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Background: Elevated Glioma-associated Oncogene Homolog-1 (Gli1) protein expression is associated with Hedgehog (Hh) pathway activation in high-grade serous ovarian cancer (HGSOC). Inhibition of Hh signaling in Gli1-overexpressing HGSOC patient-derived xenograft (PDX) inhibited tumour growth, particularly in combination with chemotherapy. Early phase HGSOC clinical trials of vismodegib, a potent Hh inhibitor (SMO inhibitor), were disappointing. We identified a HGSOC PDX harboring both Indian Hh ligand-overexpression and bi-allelic deletion of TSC1, which latter event is reported to derepress the mTOR pathway, driving non-cannonical Gli1 expression. We explored the effect of vismodegib in combination with cisplatin or the mTOR inhibitor, everolimus, in this model. Methods: A cell-line was generated from the well-characterised PDX (identity confirmed by PDX-specific p53 mutation). In vitro response to vismodegib was assessed. qRT-PCR was performed to establish Hh-ligand and Gli1 expression with/without SMO inhibition. A PDX was generated from this cell-line and randomized to in vivo treatment with cisplatin, vismodegib, everolimus or vehicle alone, or vismodegib in combination with cisplatin or everolimus. Results: The HGSOC cell-line was sensitive to vismodegib in vitro (EC50 of 3.5µM) and qRT-PCR analysis revealed down-regulation of Hh-ligand and Gli1 expression following in vitro SMO inhibition, confirming on-target vismodegib activity. In vivo treatment with vismodegib or everolimus alone did not result in reproducible in vivo efficacy. The combination of vismodegib + everolimus caused short-lived responses in 3 of 6 mice. Strikingly, in vivo treatment with vismodegib in combination with cisplatin impaired median survival (19 days) when compared with cisplatin treatment alone (43 days; p = 0.039) due to rapid tumour progression. Conclusions: Combining chemotherapy with Hh inhibition in Hh ligand-overexpressing HGSOC PDX with mTOR pathway activation may be detrimental. These findings highlight the importance of an in-depth understanding of tumour biology in order to effectively combine therapeutic approaches.

Retrospective analysis of treatment tolerability in elderly oncological patients receiving cytotoxic therapy in a community setting

e19598

Background: Cancer is highly prevalent in those above the age of 65 years. Elderly oncological patients are under-represented in clinical trials and there is a lack of clinical data to guide treatment decisions in this group of patients. We evaluated the cytotoxic treatment tolerability in this group of patients in a community hospital. Methods: Cytotoxic chemotherapies and tyrosine kinase inhibitors administered in Gold Coast Hospital to patients above 65 years of age between March 2010 and March 2011 were included. Data including number of comorbidities, concurrent medicines, ECOG status and treatment drug dose adjustment were obtained. The outcomes of treatment including treatment completion, early termination and its reason, toxicities and hospital admissions during treatment were also collected. Results: A total of 206 patients were identified. Majority had an ECOG score of 0 to 1 (89%) and number of co-morbidities between 0 and 3 (96%). Eighty percent of patients had initial or subsequent treatment dose reduction. Despite this, 53% of patients (n=109) did not complete the planned treatment; 68% had disease progression but 31% was due to treatment intolerance. There was a high number of reported grade 3 and 4 toxicities (n=84) and hospitalisations during treatment (n=154). Conclusions: There is a high rate of dose reduction and noncompletion of cytotoxic treatments even in a relatively healthy elderly population. We propose further prospective study incorporating in-depth geriatric assessment to evaluate elderly patients suitability for cytotoxic treatments. [Table: see text]

Helicobacter pylori is not the cause of sudden infant death syndrome (SIDS)

OBJECTIVES

The cause of sudden infant death syndrome (SIDS) is unknown, but our previous hypothesis proposed that Helicobacter pylori could be a causative organism. In this study, we aimed to test this hypothesis by examining gastric and tracheal tissues from a prospective cohort of SIDS infants and re-examining previously studied paraffin-fixed tissues for H. pylori.

METHODS

Fresh gastric antral and trachea specimens obtained at postmortem from nine consecutive new cases of SIDS in Perth, Western Australia were studied prospectively. Tissues were evaluated for H. pylori by rapid urease test (CLOtest), bacterial culture, histology (hematoxylin and eosin, Warthin-Starry Silver, and immmunoperoxidase staining), and polymerase chain reaction (PCR). The latter two tests were also used for the re-examination of paraffin-embedded specimens from infants who died from SIDS (n = 17) and other non-SIDS causes (n = 7) in Kansas City, Missouri.

RESULTS

Specimens from nine consecutive SIDS infants in Western Australia showed no evidence of H. pylori by any analyses. In the paraffin-embedded gastric and trachea specimens from Missouri, rod and coccoid-shaped bacteria were seen histologically in 33.3% of the specimens, but these were not typical H. pylori. Upon analysis by PCR, "H. pylori DNA" was detected in 53% (9/17) of SIDS samples versus 57% (4/7) in non-SIDS samples. In all cases the immunoperoxidase stain was negative, suggesting that PCR either 1) gave false positive results in this type of potentially contaminated postmortem specimen or 2) H. pylori DNA was indeed present but not increased in prevalence in SIDS infants.

CONCLUSIONS

H. pylori is unlikely to be an etiological agent in SIDS.

Accurate diagnosis of Helicobacter pylori. Polymerase chain reaction tests

Although PCR has improved considerably the sensitivity of the diagnosis of H. pylori infection, many studies have not shown conclusively the full potential of PCR in clinical diagnosis. In daily clinical practice, PCR does not have to be performed to establish H. pylori infection. PCR is still classified primarily as a research technique in the Helicobacter field. PCR or similar technology will expand in the future when automation and commercialized kits are available to most laboratories. The development of a noninvasive PCR test may prove useful because it may lead ultimately to the determination of the source and route of transmission of this important pathogen.

Culture of Helicobacter pylori from a gastric string may be an alternative to endoscopic biopsy

Helicobacter pylori was isolated from a swallowed string from 32 of 33 adult subjects (97%) with selective culture media. With this method, antibiotic susceptibility testing and molecular epidemiology studies of H. pylori can be carried out without the need for the collection of specimens by endoscopic biopsy.

The transmission/disequilibrium test for linkage on the X chromosome

The transmission/disequilibrium test (TDT), which detects linkage between a marker and disease loci in the presence of linkage disequilibrium, was introduced by Spielman et al. The original TDT requires families in which the genotypes are known for both parents and for at least one affected offspring, and this limits its applicability to diseases with late onset. The sib-TDT, or S-TDT, which utilizes families with affected and unaffected siblings, was introduced as an alternative method, by Spielman and Ewens, and the TDT and S-TDT can be combined in an overall test (i.e., a combined-TDT, or C-TDT). The TDT statistics described so far are for autosomal chromosomes. We have extended these TDT methods to test for linkage between X-linked markers and diseases that affect either males only or both sexes. For diseases of late onset, when parental genotypes are often unavailable, the X-linkage C-TDT may allow for more power than is provided by the X-linkage TDT alone.

Successful recovery of H. pylori from rapid urease tests (CLO tests)

OBJECTIVE

Culture of Helicobacter pylori (H. pylori) and the determination of its antibiotic susceptibility is of increasing importance with the rise in numbers of antibiotic-resistant strains. The aim of this study was to determine whether H. pylori could be successfully isolated from antral biopsies used in Rapid Urease Tests (CLOtests) in clinical practice.

METHODS

Antral biopsies from patients undergoing endoscopy were inserted into the gel of CLOtests to determine the H. pylori status of the patients. If the CLOtest was positive at the end of the endoscopy session, it was kept at ambient temperature until processed. In the laboratory, biopsies were removed from the gel and cultured on selective and nonselective media. In an attempt to enhance the recovery rate of H. pylori, a subset of positive CLOtests were kept at 4 degrees C from the time that the color change was noted until the removal of the biopsy.

RESULTS

One hundred and forty-one positive CLOtests were studied at times between 1 h and 6 h postendoscopy. Culture success was 93% in the 1st hour but fell off sharply after 2 h (p < 0.001). Isolation was also improved if positive CLOtests were stored at 4 degrees C and plated out within 4 h (p < 0.001).

CONCLUSIONS

H. pylori can be successfully cultured from biopsies in CLOtests kept at room temperature within 2 h or within 4 h if kept at 4 degrees C. Thus the antral biopsy in the CLOtest can be usefully retrieved when, in the light of the CLOtest result, the physician wishes to obtain both culture and antibiotic sensitivity results.

Influence of physician attitudes on willingness to perform abortion

OBJECTIVE

To survey attitudes about abortion in a sample of physicians practicing in the Bronx, New York, identify factors associated with those attitudes, and investigate how attitudes about abortion influence willingness to do it.

METHODS

A questionnaire mailed to obstetricians and gynecologists affiliated with a medical school in the Bronx elicited information on attitudes about abortion and the willingness to do it. Attitude scores were measured on a Likert scale ranging from 1 to 5, with 5 indicating a proponent attitude about abortion. The practice score ranged from 0 to 2, with 2 indicating proponent attitude about practicing abortion.

RESULTS

The median attitude score was 3.8. Physicians were receptive to reasons for abortion that were medically indicated. A proponent attitude was found in non-Catholics and those who were trained in residency programs that required observing abortions. The median practice score was 1.2. The most important personal factors influencing a physician's decision not to perform abortions included lack of proper training and ethical and religious beliefs. There was a significant positive correlation between the attitude score and practice score (r = .42, P < .001).

CONCLUSION

Personal beliefs and past experience with abortion are associated with attitudes about abortion that, besides competence doing them, influence physicians' willingness to do them. Offering training in abortion might benefit physicians who are proponents and willing to perform abortions.

Viral characteristics of human papillomavirus infection and antioxidant levels as risk factors for cervical dysplasia

Genital human papillomavirus (HPV) infection is the major causal factor of cervical intraepithelial neoplasia (CIN). The potential role of nutrition as an additional, independent risk factor for CIN has not been appropriately addressed in the context of HPV. This case-control study evaluated the etiologic role of HPV in terms of viral type and load and examined the association between CIN and plasma levels of micronutrients adjusting for HPV. Cases (n = 378) with histo-pathologically confirmed CIN and controls (n = 366) with no history of abnormal Pap smears were recruited from colposcopy and gynecology clinics, respectively. Risk of CIN was significantly increased among women who were infected with multiple HPV types (odds ratio [OR] = 21.06), a high viral load (OR = 13.08) and HPV 16 (OR = 62.49). After adjusting for HPV positivity and demographic factors, there was an inverse correlation between plasma alpha-tocopherol and risk of CIN (OR = 0.15). Plasma ascorbic acid was protective at a high level of > or = 0.803 mg/dl (OR = 0.46). CIN was not associated with plasma retinol and beta-carotene levels. The effect of genital HPV infection on CIN development is highly influenced by oncogenic viral type and high viral load. Vitamins C and E may play an independent protective role in development of CIN that needs to be confirmed in prospective studies.

Development of a multi-item scale to quantitatively assess sexual behaviors and the transmission of high- and low-risk human papillomaviruses

BACKGROUND

Epidemiologic research is frequently hindered by the inherent difficulty in quantifying the risk of sexually transmitted disease (STD) acquisition associated with individual patterns of sexual behavior.

GOAL OF THE STUDY

To develop a quantitative sexual behavior risk scale and demonstrate its predictive validity in an assessment of risk factors for incident infection with human papillomaviruses (HPVs).

STUDY DESIGN

Data from a prospective study of HPV infection in female university students was used to generate quantitative multi-item sexual behavior scales which were used in Cox regression analyses.

RESULTS

Although risk was incurred both in casual sexual encounters and in noncasual relationships, risk in these contexts were only weakly correlated. The construction of separate measurement scales was performed.

CONCLUSIONS

Improved precision of measurement of STD risk demonstrated that significant risk was associated with different patterns of sexual behavior and was incurred in both casual and/or noncasual relationships. Scores on the sexual behavior risk scales were highly predictive of incident infection with HPV types of both high and low oncogenic potential.

HPV 16 and cigarette smoking as risk factors for high-grade cervical intra-epithelial neoplasia

Although genital human papillomavirus (HPV) infection is well established as the etiologic agent for cervical intraepithelial neoplasia (CIN), little is known about the cofactors involved in the development of high-grade lesions or the progression of low-grade to high-grade lesions. In our study of HPV-infected women with CIN (163 CIN I, 51 CIN II and 44 CIN III), women with CIN II or III were compared with those with CIN I for risk factors associated with high-grade lesions. After controlling for age, education, ethnicity and frequency of Pap smear screening, infection with HPV 16, but not high viral load or infection with multiple types, was associated with high-grade lesions (OR for CIN II = 11.96, OR for CIN III = 23.74). Risk of CIN III, but not CIN II, increased with number of cigarettes smoked per day (ORs = 1.49 and 3.35 for < or = 10 and > 10 cigarettes per day, respectively) and decreased with frequency of condom use during sex (ORs = 0.60 and 0.32 for women who used condoms occasionally/sometimes and most/all of the time, respectively). There were no associations between high-grade lesions and plasma levels of micronutrients (retinol, beta-carotene, alpha-tocopherol and reduced ascorbic acid). Our results indicate that infection with HPV 16 is associated with high-grade lesions. Additional cofactors, such as cigarette smoking, may be required as a carcinogen to advance HPV-infected cells toward neoplastic progression.

Plasma concentrations of micronutrients during a nine-month clinical trial of beta-carotene in women with precursor cervical cancer lesions

The effects of oral supplementation of a 30-mg dose of beta-carotene on the plasma levels of carotenoids, tocopherols, and retinol were studied sequentially in 69 patients participating in a nine-month randomized placebo controlled trial conducted to examine efficacy of beta-carotene to induce regression of cervical intraepithelial neoplasia. At each visit (baseline and 1.5, 3, 6, 9, 10.5, and 15 mo), blood samples were collected and the levels of six micronutrients were determined by high-performance liquid chromatography. No limitations or changes were introduced in each participant's dietary habits. Cervico-vaginal lavage samples were also obtained at the same visit and assayed for the presence of human papillomavirus DNA by Southern blot hybridization and polymerase chain reaction. In the supplemented group, mean plasma beta-carotene levels were significantly higher (p = 0.0001) than baseline and remained markedly elevated for 15 months. In the longitudinal analysis of the placebo group, there were no variations among individual mean plasma levels of beta-carotene, alpha-carotene, lycopene, retinol, gamma-tocopherol, or alpha-tocopherol, suggesting absence of seasonal or dietary changes. In the placebo group, cigarette smoking and steroid contraceptive use were significantly associated with low levels of plasma beta-carotene (p = 0.05 and p = 0.012, respectively). However, in contrast, in the beta-carotene-supplemented group, steroid contraceptive use had no influence on the plasma beta-carotene levels. An additional noteworthy finding was that beta-carotene supplementation did not reverse the depletion effect in smokers. There was no association between the plasma levels of these six micronutrients in women with cervical intraepithelial neoplasia and persistent human papillomavirus infection status in the placebo or the supplemented groups. Functional sequential nutrient interactions with each other or with other essential micronutrients and possible long-term toxicity need to be addressed in clinical trials.

Natural history of cervicovaginal papillomavirus infection in young women

BACKGROUND

Genital human papillomavirus (HPV) infection is highly prevalent in sexually active young women. However, precise risk factors for HPV infection and its incidence and duration are not well known.

METHODS

We followed 608 college women at six-month intervals for three years. At each visit, we collected information about lifestyle and sexual behavior and obtained cervicovaginal-lavage samples for the detection of HPV DNA by polymerase chain reaction and Southern blot hybridization. Pap smears were obtained annually.

RESULTS

The cumulative 36-month incidence of HPV infection was 43 percent (95 percent confidence interval, 36 to 49 percent). An increased risk of HPV infection was significantly associated with younger age, Hispanic ethnicity, black race, an increased number of vaginal-sex partners, high frequencies of vaginal sex and alcohol consumption, anal sex, and certain characteristics of partners (regular partners having an increased number of lifetime partners and not being in school). The median duration of new infections was 8 months (95 percent confidence interval, 7 to 10 months). The persistence of HPV for > or =6 months was related to older age, types of HPV associated with cervical cancer, and infection with multiple types of HPV but not with smoking. The risk of an abnormal Pap smear increased with persistent HPV infection, particularly with high-risk types (relative risk, 37.2; 95 percent confidence interval, 14.6 to 94.8).

CONCLUSIONS

The incidence of HPV infection in sexually active young college women is high. The short duration of most HPV infections in these women suggests that the associated cervical dysplasia should be managed conservatively.

Stringent criteria for histological diagnosis of koilocytosis fail to eliminate overdiagnosis of human papillomavirus infection and cervical intraepithelial neoplasia grade 1

Overdiagnosis of HPV infection in cervical biopsies results in increased health care costs and unnecessary surgical procedures. Stringent criteria for histological diagnosis of koilocytosis were evaluated, using molecular detection of HPV DNA (polymerase chain reaction and Southern blot hybridization) as gold standard. Colposcopic biopsy specimens from 511 patients were studied, including 76 with referral diagnoses of negative cervix and 241 with CIN 1 or koilocytosis. Referral diagnoses for low-grade lesions failed to distinguish between HPV-infected and uninfected patients. False-positive rate for prediction of HPV infection was 74.8%. Biopsy specimens reevaluated using stringent diagnostic criteria showed increasing prevalence of HPV infection among patients whose biopsy specimens showed negative (43.7%), minimal (52.4%), or definite (69.5%) features of koilocytosis (P = .001). Similarly, subjects infected with high viral load or oncogenic HPV infection were more likely to be identified (P = .004 and .04, respectively). Despite increased predictive value of stringent diagnostic criteria, significant number of patients diagnosed as having CIN 1/koilocytosis (34.0%) did not in fact have HPV infection. Because most low-grade lesions spontaneously regress, patients with histological diagnosis of CIN 1 or HPV infection should be observed for a period of several months before definitive ablative treatment is undertaken.

Lymphoproliferative responses to human papillomavirus (HPV) type 16 proteins E6 and E7: outcome of HPV infection and associated neoplasia

BACKGROUND

Infection with human papillomavirus (HPV) type 16 (HPV16) is a major cause of high-grade cervical intraepithelial neoplasia (CIN). Experiments were planned to evaluate the role of cell-mediated immunity (e.g., lymphocyte proliferation) against HPV in the natural history of HPV-associated neoplasia and to identify antigenic sequences of the HPV16 proteins E6 and E7 against which an immune response may confer protection.

METHODS

Forty-nine women with abnormal cervical cytology and biopsy-confirmed CIN were followed through one or more clinic visits. Lymphoproliferative responses of peripheral blood mononuclear cells to HPV16 E6 and E7 peptides were assessed in long-term (3-week) cultures. HPV DNA was detected in cervicovaginal lavage by means of polymerase chain reaction and Southern blotting. Disease status was determined by cervical cytologic examination and colposcopy. Reported P values are two-sided.

RESULTS

Subjects with positive lymphoproliferative responses to E6 and/or E7 peptides were more likely to be HPV negative at the same clinic visit than were nonresponders (P = .039). Subjects who were negative for HPV and those with a low viral load were more likely to be responders than were those with a high viral load (P for trend = .037). Responses to N-terminal E6 peptide 369 were associated with absence of HPV infection at the same clinic visit (P = .015). Subjects with positive responses to E6 or E7 peptides at one clinic visit were 4.4 times more likely to be HPV negative at the next visit than were nonresponders (P = .142). Responses to E6 peptide 369 and/or E7 C-terminal peptide 109 were associated with an absence of HPV infection (P = .02 for both) and an absence of CIN (P = .04 and .02, respectively) at the next visit.

CONCLUSIONS

Lymphoproliferative responses to specific HPV16 E6 and E7 peptides appear to be associated with the clearance of HPV infection and the regression of CIN.

PCR detection of human papillomavirus: comparison between MY09/MY11 and GP5+/GP6+ primer systems

Human papillomavirus (HPV) is an etiologic agent of cervical cancer and is the most common sexually transmitted disease in women. PCR amplification of HPV genomes is the most sensitive method for the detection of cervicovaginal HPV. We have compared the two most commonly used PCR primer sets, MY09/MY11 (MY-PCR) and GP5+/GP6+ (GP+-PCR), for the detection of HPV DNA in cervicovaginal lavage samples from 208 women. Oligonucleotide probes for 39 different HPV types were used. Both primer sets amplified a wide spectrum of HPV genotypes and detected similar overall prevalences of 45% (94 of 208) and 43% (89 of 208), respectively. The MY-PCR system detected 27 of 30 (90%) samples with multiple HPV types, whereas the GP+-PCR system detected 14 of 30 (47%) samples with multiple HPV types. Differences in the detection of HPV types 35, 53, and 61 were noted between the two primer systems. Serial dilution of plasmid templates indicated a 3-log decrease in the amplification of HPV type 35 by MY-PCR and HPV types 53 and 61 by GP+-PCR. These results indicate that although the MY-PCR and GP+-PCR identified nearly equivalent prevalences of HPV in a set of clinical samples, differences in the detection of specific types and infections with multiple types were found. Differences in the sensitivities and characteristics of the PCR systems for the detection of HPV within clinical samples should be considered when comparing data between studies and/or in designing new studies or clinical trials.

Effects of beta-carotene and other factors on outcome of cervical dysplasia and human papillomavirus infection

Women with histopathologically confirmed cervical intraepithelial neoplasia (CIN) were followed at 3-month intervals in a randomized double-blinded trial to evaluate the efficacy of beta-carotene to cause regression of CIN. Questionnaire data, plasma levels of micronutrients, and a cervicovaginal lavage for human papillomavirus (HPV) detection were obtained at each visit, and an endpoint biopsy was performed at 9 months. Sixty-nine subjects had a biopsy endpoint evaluation; 9 of 39 (23%) subjects in the beta-carotene group versus 14 of 30 (47%) in the placebo group had regression of CIN (P = 0.039). Independent risk factors for persistent CIN at 9 months included type-specific persistent HPV infection (OR = 11.38, P = 0.006) and continual HPV infection with a high viral load (OR = 14.25, P = 0.007) at baseline and 9 months, an initial diagnosis of > or =CIN II (OR = 6.74, P = 0.016), and older age (OR for > or =25 years = 4.10, P = 0.072). After controlling for these factors, the beta-carotene and placebo groups did not differ in risk for having CIN at 9 months (OR = 1.53, P = 0.550). Resolution of baseline HPV infection was significantly correlated with non-high-risk HPV types (RR = 2.94, P = 0.015), age <25 years (RR = 2.62, P = 0.014), and douching after sexual intercourse (RR = 3.02, P = 0.012), but not with randomization group. Our data indicate that a large proportion of mild CIN lesions regress; age and HPV infection play an important role in the natural course of CIN; and repeated HPV testing may have a value in distinguishing women who need aggressive treatment for CIN versus those who do not. Supplementation of beta-carotene does not appear to have a detectable benefit in treatment of CIN.

Sexual behavior and partner characteristics are the predominant risk factors for genital human papillomavirus infection in young women

Risk factors for cervicovaginal human papillomavirus (HPV) infection were investigated in 604 college women. HPV was detected in 168 (27.8%) of the subjects by L1 consensus primer polymerase chain reaction, Southern blot hybridization, or both. Significant independent risk factors for HPV (P < .05) included age (odds ratios [ORs]: 2.6 for 21-23 years old and 1.6 for > 23, vs. < or = 20), ethnicity (ORs: 3.2 for black, 2.2 for Hispanic, vs. white/other), number of lifetime male vaginal sex partners (ORs: 4.5 for 2, 5.8 for 3 or 4, 10.3 for > or = 5, vs. 1), living with smokers (OR: 1.9), male partner's number of lifetime sex partners (ORs: 2.1 for 2 or 3, 3.1 for 4-10, 2.7 for > or = 11, vs. 1), duration of sexual relationship for > 12 months (OR: 0.6), and male partner currently in college (OR: 0.6). These data demonstrate that the predominant risk factors for genital HPV infection in young women are related not only to their own sexual behaviors but also to those of their male partners.

Persistent genital human papillomavirus infection as a risk factor for persistent cervical dysplasia

BACKGROUND

Cervical dysplasia, also referred to as squamous intraepithelial lesion (SIL) in cytology or cervical intraepithelial neoplasia in histopathology, is thought to have the potential to advance in progressive stages to cervical cancer. However, not all cases of SIL progress, and most of the mild lesions spontaneously regress. Factors that govern regression, persistence, and progression of SIL are poorly understood.

PURPOSE

Our analysis sought to identify factors that determined persistence or regression of SIL.

METHODS

Seventy subjects with histopathologically confirmed cervical dysplasia were followed at 3-month intervals for 15 months. At each visit, the cervix was evaluated by Pap smear and colposcopy, and exfoliated cervicovaginal cells were analyzed for human papillomavirus (HPV) DNA. For each subject, data from every two consecutive visits were grouped as a pair. Persistent SIL was considered present if a lesion was detected at a visit (t) as well as at the next visit (t + 1) and absent if a lesion was detected at visit t but not at visit t + 1. A statistical model for time-dependent data correlated persistent SIL with various risk factors.

RESULTS

Age, ethnicity, education, sexual behavior, smoking, and the use of oral contraceptives did not correlate with persistent SIL. The risk of persistent SIL was associated with continual HPV infection in visits t and t + 1 (HPV positive by Southern blot analysis: odds ratio [OR] = 3.91, and 95% confidence interval [CI] = 1.58-9.65; HPV positive by polymerase chain reaction [PCR]: OR = 2.42, and 95% CI = 1.03-5.67) and a persistent high viral load (OR = 4.07, and 95% CI = 1.35-12.30). When typed by PCR, individuals with type-specific persistent infection in visits t and t + 1, and particularly those with a continual high viral load (OR = 4.97; 95% CI = 1.45-17.02), had the highest risk for persistent SIL compared with those with a low level of type-specific persistent infection or non-type-specific persistent infection. The presence of persistent HPV infection in visits t-1 (the preceding time interval) was also predictive of persistent SIL in visits t and t + 1, although the strength of association was weaker, suggesting that persistent HPV and SIL occur synchronously.

CONCLUSION

HPV infection and its associated cervical lesions tend to occur concurrently, and type-specific persistent HPV infection, particularly with a high viral load, produces chronic cervical dysplasia.

IMPLICATIONS

The natural history of genital HPV infection directly influences the prognosis of cervical dysplasia as measured by persistence of the lesion. Testing for HPV infection may be valuable in the clinical management of women with cervical dysplasia.

Outcome of perinatal hepatitis B virus exposure is dependent on maternal virus load

To evaluate the role of maternal hepatitis B virus (HBV) DNA levels in perinatal infection, two nested case-control studies were done within a cohort of 773 hepatitis B surface antigen (HBsAg)-positive Taiwanese women and their infants. As serum HBV DNA levels increased from < 0.005 to > or = 1.4 ng/mL among the hepatitis B e antigen (HBeAg)-positive mothers, the odds ratio (OR) for having a persistently infected infant increased from 1.0 to 147.0 (P for trend < .001). Among HBeAg-negative mothers, the OR for having a persistently infected infant was 19.2 (95% confidence interval, 2.3-176.6) in mothers with high versus low levels of serum HBV DNA. A logistic regression analysis identified maternal HBV DNA to be a stronger independent predictor of persistent infection than HBeAg status. Thus, perinatal exposure to high levels of maternal HBV DNA is the most important determinant of infection outcome in the infant.

Risk factors for squamous intraepithelial lesions on Pap smear in women at risk for human immunodeficiency virus infection

To determine risk factors for squamous intraepithelial lesions (SIL) on Pap smear, 253 women at risk for human immunodeficiency virus (HIV) infection had Pap smear, HIV antibody testing, CD4+ cell measurements, and human papillomavirus (HPV) genome detection by Southern blot hybridization. Associated with SIL (P < .05) on univariate analysis were genital HPV (SIL prevalence in HPV-positive subjects, 36.3%; odds ratio [OR], 9.3; 95% confidence interval [CI], 4.2-20.3) and HIV infection (SIL prevalence in seropositive subjects, 21.9%; OR, 2.5; 95% CI, 1.2-5.1). No demographic or behavioral variables were associated with risk for SIL. Multivariate analyses identified genital HPV infection (OR, 6.78; 95% CI, 2.9-15.7), detection of known high-risk HPV types (OR, 11.8; 95% CI, 4.1-34.1), strong HPV Southern blot signal strength (OR, 10.8; 95% CI, 3.5-33.7), and severe HIV-related immunosuppression (OR, 3.1; 95% CI, 1.04-9.5) as independent risk factors associated with SIL. Thus, severe immunosuppression due to HIV infection increases the risk for SIL mediated by HPV infection.

Plasma renin predicts success of antihypertensive drug withdrawal

This study examined the relationship of plasma renin activity (PRA) to the likelihood of maintaining blood pressure control after discontinuation of antihypertensive medication. Patients whose blood pressure was previously treated and controlled in the Hypertension Detection and Follow-up Program were enrolled in the Dietary Intervention Study of Hypertension. After stratification by obesity, patients were randomized to discontinue medication with no dietary intervention, sodium restriction, or weight reduction for the obese. Among 496 subjects in the Dietary Intervention Study of Hypertension, 75 were randomly selected for PRA measurement at 4 months after intervention, and all had their blood pressure under control at that time. Patients were followed up for 56 weeks after randomization. The endpoint was return to antihypertensive medication due to elevated diastolic blood pressure. Kaplan-Meier survival analysis showed that subjects with PRA < or = 53.3 ng/100 mL/h, the median level, had a lower cumulative success rate for remaining off antihypertensive drug than those with PRA above the median (P = .046). In Cox regression analysis controlling for 24-h urinary sodium level, baseline diastolic blood pressure, age, sex, race, obesity, and dietary intervention group, a unit decrease in log PRA was associated with a 2.78-fold increase in risk of returning to drug (P = .006); this inverse relationship was independent of dietary intervention and change in diastolic blood pressure in the first 4 months before PRA was measured. The data indicate that patients with low PRA are less likely to maintain blood pressure control without drugs than patients with high PRA.

Risk of genital human papillomavirus infection in women with human immunodeficiency virus-induced immunosuppression

This study examined the risk factors for genital human papillomavirus (HPV) infection, including HIV-related immunosuppression as well as demographic and behavioral factors. Subjects were 207 women with known HIV serologic status, the majority of whom were intravenous drug users recruited from a methadone treatment program in the Bronx, New York. A structured questionnaire interview, cervico-vaginal lavage, and CD4 cell measurements were obtained. HPV genomes in the cervico-vaginal cells were detected by Southern-blot hybridization. HPV prevalence was 23% among HIV seronegatives, 45% among HIV seropositives with CD4 percent > 20 and 61% among HIV seropositives with CD4 percent < or = 20. Multivariate analysis identified the following independent risk factors that were significantly associated with HPV positivity: HIV-related immunosuppression, < 35 years of age, and never used oral contraceptive pills. HIV-related immunosuppression was also associated with a stronger Southern-blot signal strength. HIV infection, however, did not increase the susceptibility to HPV infection with the oncogenic types (16, 18, 31, 33 and 35). Women with HIV infection or immunosuppression had a higher prevalence of HPV infection with the oncogenic types, but they also had an increased prevalence of infection with other HPV types as compared to the HIV-seronegative women. The results suggest that HIV-related immunosuppression increases the risk of genital HPV infection and has an effect on HPV replication.

Women with human immunodeficiency virus infection and abnormal Papanicolaou smears: a prospective study of colposcopy and clinical outcome

OBJECTIVE

To determine the effect of human immunodeficiency virus (HIV) infection on colposcopic and histologic findings and clinical outcome in women who have abnormal Papanicolaou smears.

METHODS

We conducted a prospective study of women with abnormal Papanicolaou smears from among those participating in a longitudinal study of HIV infection, human papillomavirus infection, and genital neoplasia. Women with squamous intraepithelial lesions (SIL) on blindly interpreted Papanicolaou smears were referred for colposcopy and standard gynecologic care. Colposcopic and histologic findings were correlated with cytology, and differences between HIV seropositives and seronegatives were analyzed.

RESULTS

Thirty-eight of 48 women referred underwent colposcopy, of whom 36 (94.7%) had colposcopic or histologic findings no more severe than those suggested by Papanicolaou smear. Seventeen of 25 HIV seropositives (68%) had cervical or vaginal condyloma or neoplasia, compared with three of 13 seronegatives (23%) (odds ratio [OR] 7.1, 95% confidence interval [CI] 1.5-33.0). Among seropositives, seven (28%) had cervical intraepithelial neoplasia (CIN) grade II or III; ten (40%) had cervical or vaginal condyloma, CIN I, or both; and eight (32%) had no vaginal or cervical SIL. There was no case of invasive carcinoma. Seven seropositives (28%) had or developed multicentric disease, compared with no seronegatives (P = .07). Follow-up ranged at 3-37 months and showed that all three treated seronegative women and five of ten treated seropositive women had normal examinations. Three seropositive patients had persistent disease without progression, and two had progression of condyloma. No CIN II, CIN III, or invasive carcinoma was seen during follow-up.

CONCLUSIONS

Among women seropositive for HIV who had SIL on a Papanicolaou smear, colposcopic and histologic findings were predicted reliably by the cytologic smear. Rapid progression of CIN after standard gynecologic care for early genital lesions was not seen.

Markers of health status in an HTLV-I-positive cohort

The health effects of chronic human T-cell lymphotropic virus type I (HTLV-I) infection were examined in a cohort of Japanese men who had emigrated from Okinawa, Japan, and had been participants in a prospective study in Hawaii since 1965. In the present follow-up study carried out in 1987-1988, various health indicators were measured in the subjects, whose mean age was 72.5 years. Participation rates were lower in the HTLV-I seropositives than in the seronegatives (46.7% vs. 76.0%) in the > or = 75-year age group. Lack of participation was significantly correlated with a high HTLV-I antibody titer. Among the participants, seropositive subjects were significantly more likely than the seronegatives to have lymphocytopenia (32.7% vs. 17.7%) and mild anemia (25.5% vs. 14.1%) after adjustment for age and socioeconomic status. The seropositives also had a higher frequency of acupuncture therapy (age-adjusted odds ratios were 2.1 and 4.2 for 1-5 treatments and > or = 6 treatments, respectively). Proportions of subjects who had been hospitalized at least twice were higher among the seropositives in the oldest age groups, 70-74 years and > or = 75 years, but not in those aged 65-69 years. Although specific disease conditions were not identified in this study, hematologic data, treatment histories, and the correlation between participation status and HTLV-I antibody titers suggest that chronic HTLV-I infection may be associated with as yet undefined adverse health effects, particularly in older age groups.

Declining seroprevalence and transmission of HTLV-I in Japanese families who immigrated to Hawaii

This study examined the seroprevalence and transmission of human T cell lymphotropic virus type I (HTLV-I) in Japanese families who originated in Okinawa, an area in which HTLV-I is endemic, and who were currently residing in Hawaii, a nonendemic area. Among a cohort of Japanese men whose sera were collected in Hawaii in 1967-1975, those of Okinawan ancestry had an HTLV-I seroprevalence of 11.4%. This study, conducted in 1987-1988, sampled 142 index subjects from this male cohort and tested them along with their wives, children, and spouses of the children for HTLV-I antibodies. Seropositivity in their wives was 11.4% and 41.2% among the seronegative and seropositive index subjects, respectively; seropositivity also increased from 29.4% to 35.3% to 58.8% with the husbands' increasing antibody levels by tertiles. Elevated antibody levels may be a marker for infectivity, which is associated with more efficient sexual transmission of HTLV-I. The age-adjusted odds ratio for the association of seropositivity between husband and wife, however, was four times lower than that reported among native Okinawans. In addition, a substantially low seroprevalence (1.3%) was found among their offspring. The decline in HTLV-I transmission in this migrant population may be due to low infectivity in the parent generation who live in a nonendemic environment, increasing numbers of offspring marrying outside of the Okinawan community, and improved living circumstances.

Human papillomavirus infection and other risk factors for cervical neoplasia: a case-control study

A case control design has been used to investigate risk factors associated with the development of cervical squamous intraepithelial lesions (SIL) in a population of urban women in which non-affluent minority groups were heavily represented. Eighty-five women with histologically confirmed SIL were compared to a control group of 70 cytologically normal women. HPV infection was determined using both Southern blot hybridization and polymerase chain reaction (PCR) amplification specific for HPV types 16, 18, and 33. When Southern blot was used to detect HPV, logistic regression analysis identified HPV infection (odds ratio (OR) = 17.9, 95% confidence interval (CI) = 6.2-51.6) and low educational achievement (OR = 3.4, 95% CI = 1.2-10.1) as major independent risk factors. When PCR was employed to detect HPV, the logistic regression model suggested that HPV infection (OR = 10.4, 95% CI = 3.6-30.4) and Hispanic ethnicity (OR = 5.0, 95% CI = 1.2-20.5) represented independent risk factors; low educational achievement and Black ethnicity were risk factors of borderline significance. PCR detection of simultaneous co-infection with more than one HPV type was associated with a very high risk of SIL (OR for one type = 7.2, 95% CI = 2.4-21.9; OR for greater than I type = 43.0, 95% CI = 6.9-266.6). Furthermore, increased viral load determined by either method carried an increased risk of disease. HPV infection with viral types previously reported to be related to neoplastic or dysplastic lesions carried the highest risk of SIL. The association of HPV detected by Southern blot and SIL in women less than 35 years old had an OR of 10.1, whereas in women greater than or equal to 35 the OR was 74.5 (p = 0.09 for homogeneity of ORs). We conclude that infection with HPV is the major risk factor for cervical SIL and suggest that targeted HPV screening of women over age 35 may represent an innovative strategy to detect women at high risk of cervical neoplasia.

Human T-cell lymphotropic virus type I (HTLV-I) antibodies in pre-diagnostic serum of patients with familial adult T-cell leukemia/lymphoma (ATL)

In a study of 7498 American men of Japanese ancestry in Hawaii, 26 incident cases of leukemia or non-Hodgkin's lymphoma were identified after a follow-up period of 19 years. Two of the cases, who were brothers, were diagnosed with adult T-cell leukemia/lymphoma (ATL). Both of these brothers had human T-cell lymphotropic virus type I (HTLV-I) antibodies in their stored serum which were obtained 4 and 18 years before diagnosis. None of the 24 patients with other hematologic malignancies or the 26 matched controls were HTLV-I antibody positive. This finding lends further support for a role of HTLV-I in the etiology of adult T-cell leukemia/lymphoma.

The effects of distance from primary treatment centers on survival among patients with multiple myeloma

Twenty-one comprehensive cancer centers participated in a national reporting system of common data items, recording information on all patients seen between 1977 and 1982. There were 240,531 patients who had data abstracted. This report describes 1,479 patients with multiple myeloma. Parameters that may effect the type of treatment given during the initial episode of therapy in the center and the effect of these characteristics on survival were studied. In the univariate analysis, age, treatment, and distance traveled to the center were statistically associated with survival. In a multivariate analysis adjusting for potentially confounding covariates, blacks survive better than whites and the effects of sex and socioeconomic status (SES) on survival approach significance. Survival consistently improved with increasing distance traveled to treatment centers. This may be a serious confounding variable in assessing the results by both single and multiinstitution clinical trials.

Modes of transmission and evidence for viral latency from studies of human T-cell lymphotrophic virus type I in Japanese migrant populations in Hawaii

Human T-cell lymphotrophic virus type I (HTLV-I) seroprevalence was 20% among Hawaiian Japanese migrants (issei) and their offspring (nisei) from Okinawa compared to 35% in similarly aged men who were lifetime residents of Okinawa. A control group of migrants from a nonendemic area of Japan, Niigata, had low rates of HTLV-I antibodies, suggesting that Hawaii per se is not an endemic area for HTLV-I. Factors that were significantly associated with seropositivity in the Okinawa migrant groups were years of residence in Japan before migration (issei) and age for offspring of Okinawa migrants (nisei). Antibody titer was highest in Okinawa lifetime residents, intermediate in migrants (issei), and significantly lower in offspring of Okinawa migrants (nisei), with increasing titer observed with advancing age in the offspring of the migrant group. Based on these data, infection within the household occurring early in life appears to be a major route of HTLV-I transmission and may help to explain the curious geographic clustering of this virus in certain locales. As yet to be defined cofactors, including sexual transmission and/or environmental exposures (e.g., particularly before age 20), also may contribute to HTLV-I seropositivity. The pattern of rising seroprevalence and titer with age in the offspring of migrants who resided all of their lives in Hawaii raises the possibility that HTLV-I infection acquired early in life may become dormant and reexpressed with reactivation of latently infected T cells. The importance of this model in the process of viral leukemogenesis is supported by recent reports of adult T-cell leukemia in offspring (nisei) of Okinawa migrants.