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Michele Follen

Publications and source records attributed to Michele Follen.

At least 55 records · Page 3Linked to original sources

Quality assurance system using statistical process control: an implementation for image cytometry.

AIMS: Optical technologies have shown some promise for improving the care of cervical neoplasia. We are currently evaluating fluorescence and reflectance spectroscopy and quantitative cyto-histopathology for cervical neoplasia screening and diagnosis. Here we describe the establishment and application of a quality assurance (QA) system for detecting system malfunctions and assessing the comparability of four image cytometers used in a multicenter clinical trial. METHODS: Our QA system involves three levels of evaluation based on the periodicity and complexity of the measurements. We implemented our QA system at three image cytometers at the British Columbia Cancer Agency and one at M.D. Anderson Cancer Center. The measurements or tasks were performed daily, monthly, and semi-annually. The current and voltage of the lamp, the calibration image characteristics, and the room temperature were checked daily. Long-term stability over time, short-term variability over time, and spatial response field uniformity were evaluated monthly. Camera linearity was measured semi-annually. Control charts based on statistical process control techniques were used to detect when the system did not perform optimally. RESULTS: Daily measurements have shown good consistency in room temperature, lamp and calibration behaviour. Monthly measurements have shown small coefficients of variation between and within the four devices. There have been greater differences between sessions than within sessions. Comparability among the four systems is reasonably good. Semi-annual measurements have shown stable camera linearity. QA events were detected using the QA system. Multiple examples of event detection leading to correction of system malfunction are described in this report. CONCLUSIONS: QA programs are critical for ensuring data integrity and therefore for the conduct of multicenter clinical trials.

Female↗

Cervical cancer chemoprevention, vaccines, and surrogate endpoint biomarkers.

At the Second International Conference on Cervical Cancer, held April 11-14, 2002, experts in cervical cancer prevention, detection, and treatment reviewed the need for more research in chemoprevention, including prophylactic and therapeutic vaccines, immunomodulators, peptides, and surrogate endpoint biomarkers. Investigators and clinicians noted the need for more rigorous Phase I randomized clinical trials, more attention to the risk factors that can affect study results in this patient population, and validation of optical technologies that will provide valuable quantitative information in real time regarding disease regression and progression. They discussed the role of the human papillomavirus (HPV) in cervical cancer development and the importance of developing strategies to suppress HPV persistence and progression. Results in Phase I randomized clinical trials have been disappointing because few have demonstrated statistically significant regression attributable to the agent tested. Researchers recommended using a transgenic mouse model to test and validate new compounds, initiating vaccine and immunomodulator trials, and developing immunologic surrogate endpoint biomarkers.

Biomarkers, Tumor↗

Optical imaging of the cervix.

Recent advances in fiber optics, sources and detectors, imaging, and computer-controlled instrumentation have stimulated a period of unprecedented growth in the development of photonics technologies for a wide variety of diagnostic and therapeutic clinical applications. These include the application of quantitative optical spectroscopy and imaging for the detection of precancerous lesions in the uterine cervix, a topic of interest at the Second International Conference on Cervical Cancer, which was held April 11-14, 2002. Investigators have applied the Littenberg method of emerging technology assessment to new optical methods used to detect cervical neoplasia. Currently, such technologies as fluorescence spectroscopy (the combination of fluorescence and diffuse reflectance spectroscopy), tri-modal spectroscopy, and light-scattering spectroscopy that probe the spectral characteristics of tissue are being investigated. Optical technologies that create images of subcellular structure without biopsy subsequent to pathology that currently are under investigation include in vivo confocal imaging and optical coherence tomography. Numerous small studies have demonstrated the potential of these optical technologies. What remains to be elucidated are the fundamental biophysical origins of variations in remitted optical signals between normal and dysplastic tissue. Large multicenter randomized controlled trials are needed to confirm the detection and imaging capabilities of optical technology. Furthermore, the development of contrast agents that could boost detection with these technologies is needed, and basic biologic characterization of signals should be pursued. Applying the Littenberg assessment will help ensure that superior, not simply alternative, technologies are implemented.

Cervix Uteri↗

Imaging in cervical cancer.

Cervical cancer traditionally has been staged clinically. Advances in imaging could improve the staging of cervical cancer by facilitating the detection of lymph node metastases and micrometastases in distant organs. Such progress could lead to improvements in treatment selection and therefore increase overall survival rates. At the Second International Conference on Clinical Cancer (Houston, TX, April 11-14, 2002), a panel composed of gynecologic oncologists, radiation oncologists, and diagnostic radiologists reviewed relevant technologies. Advances in lymphangiography, ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and lymphatic mapping were reviewed, along with the impact of these advances on the diagnosis, treatment, and survival of patients with cervical cancer. Few cancer centers still use lymphangiography, but the sensitivity of this method ranges from 28% to 83%, with specificity ranging from 47% to 100%. The roles of transabdominal and transvaginal ultrasonography in evaluating cervical cancer are expected to expand when new contrast agents increase the sensitivity of these techniques to parametrial invasion and lymph node metastases; meanwhile, ultrasonography's most significant contributions may involve the identification of uterine and cervical leiomyomas and the evaluation of urinary tract obstruction. Advances in CT have made it a rival technique to MRI, but limitations prevent CT from providing definitive information on certain parameters. MRI, which is valuable because of its superior soft tissue contrast resolution, multiplanar capabilities, and cost-effectiveness, is used to determine the size of the cervix and to detect certain types of invasion, characteristics of lymph nodes, and the presence of disease in the ureter, lung, and liver. PET with 2-[fluorine-18]fluoro-2-deoxy-D-glucose has been found to detect abnormal lymph node regions better than CT does but PET can also be used in conjunction with CT to measure tumor dimensions. PET also has become a method for identifying tumors that are unresponsive to chemoradiation. When used together with immunohistochemical and molecular techniques as well as conventional stains, sentinel lymph node mapping, an important development in the surgical management of solid tumors, is expected to improve gynecologic cancer management. Advances in imaging methods and in contrast agents, along with advances in the combined use of the two, are expected to make imaging technologies more valuable in cervical cancer assessment.

Diagnostic Imaging↗

Serum levels of insulin-like growth factor I and risk of squamous intraepithelial lesions of the cervix.

Squamous intraepithelial lesions (SILs) are areas of precancerous growth in the cervix that can be indicative of future cervical cancer. Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) have been implicated in cancer development. Recent studies have demonstrated that elevated plasma IGF-I levels are associated with increased risk of prostate, lung, colon, and breast cancers. In this case-control study, we analyzed the relationship between serum levels of IGF-I and IGFBP-3, and SILs of the cervix. The case patients were comprised of 267 women treated at The University of Texas M. D. Anderson Cancer Center Colposcopy Clinic in Houston, Texas for abnormal Pap smears. The clinic serves minority and economically disadvantaged women referred from the County Health Department clinics of Harris County, Texas. The control subjects were 238 healthy women receiving family planning and screening services at two Harris County Health Department clinics. Case patients with either high-grade or low-grade SILs had significantly higher serum levels of IGF-I, IGFBP-3, and molar ratios of IGF-I:IGFBP-3 than the control subjects did. IGF-I levels in the highest quartile were associated with significantly higher risk of SILs compared with the lowest quartile, independent of IGFBP-3 levels. The odds ratio for the fourth quartile of IGF-I level, relative to the first quartile, was 8.54 (95% confidence interval, 4.15-17.60; P < 0.0001) after adjustment for age, ethnicity, smoking status, and IGFBP-3 level. There was a dose-response relationship between risk of SILs and the level of IGF-I: as the level of IGF-I increased, so did the risk of SILs. In addition, the serum level of IGFBP-3 was significantly higher in case patients than in control subjects. However, after adjustment for IGF-I, no relationship was evident between IGFBP-3 level and risk of SILs. Serum levels of IGF-I may be a useful biomarker for assessing risk of SIL development.

Adult↗

Real-time vital optical imaging of precancer using anti-epidermal growth factor receptor antibodies conjugated to gold nanoparticles.

Recent developments in photonic technology provide the ability to noninvasively image cells in vivo; these new cellular imaging technologies have the potential to dramatically improve the prevention, detection, and therapy of epithelial cancers. Endoscope-compatible microscopies, such as optical coherence tomography and reflectance confocal microscopy, image reflected light, providing a three-dimensional picture of tissue microanatomy with excellent spatial resolution (1-10 micro m). However, their ability to image molecular biomarkers associated with cancer is limited. Here, we describe a new class of molecular specific contrast agents for vital reflectance imaging based on gold nanoparticles attached to probe molecules with high affinity for specific cellular biomarkers. The application of gold bioconjugates for vital imaging of precancers is demonstrated using cancer cell suspensions, three-dimensional cell cultures, and normal and neoplastic fresh cervical biopsies. We show that gold conjugates can be delivered topically for imaging throughout the whole epithelium. These contrast agents have potential to extend the ability of vital reflectance microscopies for in vivo molecular imaging. They can potentially enable combined screening, detection, and therapy of disease using inexpensive imaging systems; such tools could allow mass screening of diseases such as cancer in resource-poor settings.

Antibodies, Monoclonal↗

Lymphangioma circumscriptum of the vulva: a review of the literature.

OBJECTIVE: To promote proper identification and management of this rare entity by presenting a review of the literature, a case report, and illustrations of its presentation and pathology. DATA SOURCES: Sources searched included the literature contained in the National Library of Medicine's PubMed database, using the term "lymphangioma circumscriptum" combined with "vulva." Other search terms used were "capillary lymphangioma," "lymphangiectasia," and "dermal lymphangioma." Sources also included articles predating the PubMed database that were cited by other writers. METHODS OF STUDY SELECTION: Selections were restricted to the English-language medical literature published since 1960, and the search resulted in retrieval of 3272 published papers about lymphangioma. TABULATION, INTEGRATION, AND RESULTS: Congenital lymphangioma circumscriptum of the vulva has been reported in 11 patients, including one case reported and illustrated in this paper, and acquired lymphangioma circumscriptum has been reported in 20. It affects females 9-76 years old (mean 42.5 years). Clinically, it is characterized by persistent clusters of thin-walled vesicles filled with clear fluid. The diagnosis is usually made by biopsy, as these lesions often mimic such infectious diseases as molluscum contagiosum. Management options have included surgical excision of the skin and subcutaneous tissue, surface abrasion by laser or sclerosing therapy, and observation. CONCLUSION: From this comprehensive review, which includes the clinicopathologic features of both the congenital and acquired forms, illustrations from the rarest form, and a summary of treatment approaches, we conclude that lymphangioma circumscriptum poses a diagnostic challenge the risks of which are misdiagnosis and mistreatment. These risks would likely be reduced were a database of cases accessible that permitted long-term follow-up and better assessment of presenting characteristics and treatment options.

Adult↗

Transduction of adenovirus-mediated wild-type p53 after radiotherapy in human cervical cancer cells.

OBJECTIVE: Radiotherapy is the mainstay of treatment for advanced cervical cancer and most cervical cancers have evidence of HPV (human papilloma virus) infection, which inactivates the p53 gene. The goal of this study was to determine the effect of combining radiotherapy and Adp53 infection on the growth of cervical carcinoma cells. METHODS: The silta cervical carcinoma cell line contains wild-type p53 and HPV 16 infection. The C33A cell line has a p53 mutation. The Adp53 recombinant adenovirus contains the cytomegalovirus promoter, wild-type p53 cDNA, and a polyadenylation signal in a minigene cassette inserted into the El-deleted region of a modified adenovirus 5. Transduction efficiency was assessed by using an adenovirus containing the Escherichia coli beta-galactosidase gene and expression of wild-type p53 in infected cells was evaluated by Western blot analysis. One group of cells was irradiated prior to infection, the other group received no irradiation, but were either infected with virus or mock-infected. Cells were analyzed for viability 1 to 7 days after infection by using the sulforhodamine B assay. The percentage of cells undergoing apoptosis was determined by using a TUNEL assay. RESULTS: Fifty percent of C33A cells were transduced with 5 muthplicities of infection of virus whereas SiHa cells required 25 multiplicities of infection. Adp53 expression was found 48 h after infection. In the cells treated with both radiation and Adp53 infection growth inhibition was increased compared with inhibition resulting with either treatment alone. The combination treatment also increased the percentage of cells undergoing apoptosis. CONCLUSION: Combining radiotherapy with Adp53 infection increases the inhibition of growth of cervical cancer cells in vitro. This combination treatment has the potential of increasing efficacy and of therapy.

Adenoviridae↗

Biomarkers and their use in cervical cancer chemoprevention.

Cervical cancer chemoprevention agents under study include diet and micronutrients (particularly beta-carotene, folate, and vitamins A, C, and E); medications such as retinoids (retinyl acetate gel, all-trans-retinoic acid, and 4-hydroxyphenylretinamide) that are chemically related to micronutrients; and other chemopreventives meant to affect the carcinogenic process at the cellular level, including such polyamine synthesis inhibitors as alpha-difluoromethylornithine. Agents become reasonable candidates for study when they have a biologic rationale, they are of low toxicity, and they can be taken for a long period of time. Since the human papillomavirus (HPV) is the major etiologic agent, the medication should show activity against HPV-positive preinvasive and invasive cell lines. The medication needs to be of low toxicity because it may be taken for long periods of time and less toxicity is tolerated in the precancerous setting. Until 1995, none of the studies used surrogate end point biomarkers (SEBs), relying instead on histologic and colposcopic regression as end points. All studies typically included subjects with cervical intraepithelial neoplasia. Conclusions to be drawn from these studies include the following: Though micronutrients are logical candidates for chemoprevention, they haven't worked consistently, and the reasons remain unclear. Furthermore, SEBs need to be validated in phase I trials. Finally, a better understanding of the role of HPV needs elucidation, including an understanding of the relationship of the medication to HPV status and of the immunobiology of HPV throughout the trial.

Anti-Inflammatory Agents, Non-Steroidal↗

Patient distress and satisfaction with optical spectroscopy in cervical dysplasia detection.

OBJECTIVE: The aim of this investigation was to evaluate the impact of optical spectroscopy, a new approach for the detection of cervical dysplasia, on patient well-being and satisfaction. STUDY DESIGN: Patient distress and satisfaction with optical spectroscopy compared with the Papanicolaou test and colposcopically directed biopsy were measured in a volunteer sample of 314 women with no history of abnormal Papanicolaou test findings. RESULTS: Participants reported significantly less pain and anxiety (P<.001) during optical spectroscopy than during the Papanicolaou test or colposcopically directed biopsy. Generally, participants found spectroscopy equal to the Papanicolaou test and to biopsy on a variety of questions that measured satisfaction. There were statistically significant differences between spectroscopy and the Papanicolaou test or biopsy on issues such as the discomfort and fear caused by the test, the amount of time taken, the room lighting, and perceptions of accuracy. CONCLUSION: That patients reported less distress during spectroscopy than during a Papanicolaou test, colposcopy, or biopsy suggests the possibility of improved adherence to cervical cancer screening and follow-up in settings in which it is used.

Adult↗

Light scattering from cervical cells throughout neoplastic progression: influence of nuclear morphology, DNA content, and chromatin texture.

A number of noninvasive fiber optic optical technologies are under development for real-time diagnosis of neoplasia. We investigate how the light scattering properties of cervical cells are affected by changes in nuclear morphology, DNA content, and chromatin texture, which occur during neoplastic progression. We used a Cyto-Savant computer-assisted image analysis system to acquire quantitative nuclear features measurements from 122 Feulgen-thionin-stained histopathologic sections of cervical tissue. A subset of the measured nuclear features was incorporated into a finite-difference time-domain (FDTD) model of cellular light scattering. The magnitude and angular distribution of scattered light was calculated for cervical cells as a function of pathologic grade. The nuclear atypia strongly affected light scattering properties. The increased size and elevated DNA content of nuclei in high-grade lesions caused the most significant changes in scattering intensity. The spatial dimensions of chromatin texture features and the amplitude of refractive index fluctuations within the nucleus impacted both the angular distribution of scattering angles and the total amount of scattered light. Cellular scattering is sensitive to changes in nuclear morphology that accompany neoplastic progression. Understanding the quantitative relationships between nuclear features and scattering properties will aid in the development of noninvasive optical technologies for detection of precancerous conditions.

Cell Nucleus↗

Light scattering from normal and dysplastic cervical cells at different epithelial depths: finite-difference time-domain modeling with a perfectly matched layer boundary condition.

The finite-difference time-domain (FDTD) method provides a flexible approach to studying the scattering that arises from arbitrarily inhomogeneous structures. We implemented a three-dimensional FDTD program code to model light scattering from biological cells. The perfectly matched layer (PML) boundary condition has been used to terminate the FDTD computational grid. We investigated differences in angle-dependent scattering properties of normal and dysplastic cervical cells. Specifically, the scattering patterns and phase functions have been computed for normal and dysplastic cervical cells at three different epithelial depths, namely, basal/parabasal, intermediate, and superficial. Construction of cervical cells within the FDTD computational grid is based on morphological and chromatin texture features obtained from quantitative histopathology. The results show that angle-dependent scattering characteristics are different not only for normal and dysplastic cells but also for cells at different epithelial depths. The calculated scattering cross-sections are significantly greater for dysplastic cells. The scattering cross-sections of cells at different depths indicate that scattering decreases in going from the superficial layer to the intermediate layer, but then increases in the basal/parabasal layer. This trend for epithelial cell scattering has also been observed in confocal images of ex vivo cervical tissue.

Algorithms↗

Effects of biographical variables on cervical fluorescence emission spectra.

Diagnostic algorithms can classify tissue samples as diseased or nondiseased based on fluorescence emission collected from the intact cervix. Such algorithms can distinguish high-grade squamous intraepithelial lesions from low-grade squamous intraepithelial lesions. An understanding of the effects of the values of biographical covariates, such as age, race, smoking, or menopausal status on the emission spectra for each patient could improve diagnostic efficiency. The analysis described was performed using data collected from two previously published clinical trials; one study measured spectra from 395 sites in 95 patients referred to a colposcopy clinic with abnormal Pap smears, and the second study measured spectra from 204 sites in 54 patients self-referred for screening and expected to have a normal Pap smear. For this analysis, data about age, race, menstrual cycle, and smoking were collected. The principal components from normalized data were compared. There are clear intensity differences observed with age and menopausal status; postmenopausal patients exhibit higher emission intensities. Differences associated with biographical variables need to be tested in larger studies, which stratify adequately for these variables. The addition of these biographical variables in the preprocessing of data could dramatically improve algorithm performance and applicability.

Adult↗

Use of nuclear morphometry characteristics to distinguish between normal and abnormal cervical glandular histologies.

This is a methodological study exploring the use of quantitative histopathology applied to the cervix to discriminate between normal and cancerous (consisting of adenocarcinoma and adenocarcinoma in situ) tissue samples. The goal is classifying tissue samples, which are populations of cells, from measurements on the cells. Our method uses one particular feature, the IODs-Index, to create a tissue level feature. The specific goal of this study is to find a threshold for the IODs-Index that is used to create the tissue level feature. The main statistical tool is Receiver Operating Characteristic (ROC) curve analysis. When applied to the data, our method achieved promising results with good estimated sensitivity and specificity for our data set. The optimal threshold for the IODs-Index was found to be 2.12.

Adenocarcinoma↗

Detecting the signal of the menstrual cycle in fluorescence spectroscopy of the cervix.

Fluorescence spectroscopy of the cervix has been shown to be an effective noninvasive diagnostic tool for cervical intraepithelial neoplasia (precancer). To assess the effect of the menstrual cycle on fluorescence spectroscopy, daily measurements were made on ten subjects for the length of their cycle. These measurements were analyzed to determine if there was a statistically significant signal associated with the menstrual cycle. A signal was found for emission wavelengths between 425 and 445 nm inclusive--near the main hemoglobin absorption band, the Soret band, at 420 nm. We suspect that the slight displacement of the Soret band is due to the nearby dominant NAD(P)H peak, which increases the signal-to-noise ratio and affects statistical significance. The signal consists of a reduction in fluorescence intensity for the first few days of the cycle. This analysis indicates that hemoglobin absorption is the main menstrual-cycle effect on the use of fluorescence spectroscopy on the cervix. The effect is confined to a small set of excitation/emission wavelengths and to approximately the first 8 days of the cycle. This suggests that any problems from the menstrual cycle can be avoided with a simple requirement that the device not be used during the period of menstrual bleeding.

Adult↗

Microanatomical and biochemical origins of normal and precancerous cervical autofluorescence using laser-scanning fluorescence confocal microscopy.

Clinical studies have shown that in vivo fluorescence spectroscopy can improve the diagnosis of cervical precancer. Recent work suggests that epithelial fluorescence increases, whereas stromal fluorescence decreases, with precancer. However, the microanatomic and biochemical sources of fluorescence in living cervical tissue have not yet been established. This study aims to characterize the origins of living normal and precancerous cervical fluorescence at microscopic levels using laser-scanning fluorescence confocal microscopy. Ten pairs of colposcopically normal and abnormal biopsies were obtained; transverse, 200 microm thick, short-term tissue cultures were prepared and imaged when viable with UV (351-364 nm) and 488 nm excitation before and after addition of the vital dye, Mitotracker Orange. In normal epithelium basal epithelial cells showed cytoplasmic fluorescence; parabasal, intermediate and superficial cells showed fluorescence only at the periphery of the cell. In low-grade precancers cytoplasmic fluorescence was visible in the bottom one-third of the epithelium; in high-grade precancers cytoplasmic fluorescence was visible throughout the lower two-thirds of the epithelium. Cytoplasmic fluorescence was colocalized with the MitoTracker probe and is attributed to mitochondrial reduced form of nicotinamide adenine dinucleotide at UV excitation and mitochondrial flavin adenine dinucleotide at 488 nm excitation. Stromal fluorescence originated from matrix fibers; with the development of precancer the density and fluorescence intensity of matrix fibers decrease. Autofluorescence properties of precancerous cervix reflect an increased number of metabolically active mitochondria in epithelial cells and a reduced stromal fluorescence, which can be an indicator for altered communication between precancerous epithelium and stroma. These changes can explain differences in in vivo fluorescence spectra of normal and precancerous cervical tissue.

Cervix Uteri↗

Relationship between collagen autofluorescence of the human cervix and menopausal status.

The goal of this study was to evaluate the effect of different menopausal states (pre- and post-) on the endogenous fluorescence of normal cervical tissues. In particular, the average fluorescence as well as the interpatient and intrasample variability in the average fluorescence of the epithelium and stroma were evaluated as a function of pre- and postmenopausal states. High-resolution fluorescence images at excitation-emission wavelengths of 440, 520 nm and 365, 465 nm were obtained from epithelia and stroma of freeze-trapped cervical tissue blocks maintained at -196 degrees C. The fluorescence images were recorded using a low temperature optical scanner. Fluorescence images from a normal sample population (n = 27) were quantitatively analyzed, and the average epithelial and stromal fluorescence intensities were obtained. Data grouped according to menopausal status (pre- vs post-) showed statistically significant differences (P < 0.002) in stromal fluorescence. In particular, the cervical stroma of postmenopausal women showed (1) significantly greater average fluorescence and (2) greater interpatient and intrasample variability in the fluorescence, relative to that of premenopausal women. These results provide evidence for changes in collagen cross-linking with menopause.

Adult↗

Effect of 4-hydroxyphenylretinamide on human cervical epithelial and cancer cell lines.

Topical trans-retinoic acid treatment produced a statistically significant regression of cervical intraepithelial neoplasia (CIN) 2, but not CIN 3, in trials. A promising oral retinoid, 4-hydroxyphenylretinamide (4-HPR) induced apoptosis through non-retinoic acid-mediated pathways and is being studied in National Cancer Institute phase II trials in several organ sites. We studied the effects of 4-HPR on cervical cancer cell lines and on cervical epithelial cell lines immortalized by human papillomavirus (HPV). Four immortalized cervical epithelial cell lines (in vitro models of precancerous CIN lesions) and nine cervical carcinoma cell lines were studied. The growth inhibitory effect of 4-HPR was tested in monolayer culture and in semisolid medium, and concentrations required for a 50% growth inhibition within 5 days were determined. The agent 4-HPR inhibited the growth of cervical carcinoma cell lines and HPV-immortalized cell lines in a dose- and time-dependent fashion. Doses of 5 and 10 microM were more effective than 1 microM. The C33A cell line was most sensitive to 4-HPR, and HeLa and HT3 were the least sensitive. Of the HPV-immortalized cell lines, Z132, an HPV-16 immortalized cell line, was sensitive; the HPV 18-immortalized cell lines (Z173, Z183, and TCL-1) were not, although they were sensitive when grown in colonies. The agent 4-HPR is active against several cervical cancer cells lines and HPV-immortalized cervical epithelial cell lines. These findings are consistent with data from other laboratories studying other organ systems. This study helps establish a relevant biologically active dose for clinical trials in the cervix, one corresponding to the 5- and 10-microM tissue doses.

Cell Division↗