Abstract P6-08-09: Incidence and risk factors for congestive heart failure in early breast cancer received anthracycline and/or trastuzumab; big-data analysis of Korean health insurance review and assessment service database

Background: Anthracycline (AC) and/or trastuzumab (T) are the most commonly used for neo-/adjuvant therapy for early breast cancer. However, use of those regimens are limited owing to congestive heart failure (CHF). Although reported incidence from pivotal trials is very low and acceptable, no big data-based population study has not been conducted in Koreans yet. The aim of this study was to analyze the incidence, time to occurrence, and risk factors for CHF in patients with early breast cancer, who were treated with AC and/or T therapy, in Korea.

Methods: We used the Health Insurance Review and Assessment Service database and included women with no prior history of CHF who were aged >19 years and diagnosed as having early breast cancer between 2007 and 2016. Only patients who had received breast cancer surgery and AC and/or T therapy were included. Patients with metastatic cancer codes were excluded.

Result: In total, 86,086 patients were included for this analysis. The incidence and median time to occurrence of CHF according to chemotherapy type were, 3.27% and 683.5 days in the AC only group, 6.39% and 374 days in the AC followed by T group, and 4.43% and 286 days in the T with or without non-AC group, respectively.

The multivariate Cox regression analysis revealed that the adjusted hazard ratio (HR) for CHF was increased with older age; in those aged ≥65 years versus <50 years (HR, 2.79; 95% confidence interval [CI], 2.50–3.12). The HR in the AC followed by T group was significantly higher than that in the AC only group (HR, 2.21; 95% CI, 2.05-2.37). The T with or without non-AC group also showed a significantly higher HR than the AC only group (HR, 1.67; 95% CI, 1.37-2.04). CCI scores of ≥2 were significant predictors of CHF; score 2 versus 0 (HR, 1.30; 95% CI, 1.18-1.45), and score ≥3 versus 0 (HR, 1.87; 95% CI, 1.69-2.06). In addition, preexisting medical conditions were significant predictors for CHF: hypertension (HR, 1.58; 95% CI, 1.45-1.72), diabetes (HR, 1.17; 95% CI, 1.07-1.28), and ischemic heart disease (HR, 1.60; 95% CI, 1.45-1.76).

Conclusion: This is the first big data-based population study in Korea on the development of CHF after treatment with AC and/or T. The overall incidence of CHF was 3% to 6%, with a median time to occurrence of 1 to 2 years. Adjusted HR increased with older age, AC followed by T therapy, CCI scores ≥2, and preexisting conditions.

Table 1. Incidence and median time to occurrence of congestive heart failure according to chemotherapy typeChemotherapy typeTotalCHF event (%)Median time to occurenceAC only66,6992,182 (3.27%)683.5AC followed by T17,0621,090 (6.39%)374T ± non-AC2,325103 (4.43%)286

Table 2. Cox proportional hazards model for congestive heart failure, adjusted for age, chemotherapy type, and Charlson comorbidity index scoreVariableP-valueHR95% CIAge (ref <50 years)   50-64 years<0.00011.541.43-1.66≥65 years<0.00012.792.50-3.12Chemotherapy type (ref AC only)   AC folloewed by T<0.00012.212.05-2.37T ± non-AC<0.00011.671.37-2.04Charlson comorbidity index score (ref 0)   10.12061.080.98-1.192<0.00011.301.18-1.45≥3<0.00011.871.69-2.06

Citation Format: Choi JY, Cho EY, Lee JW, Kim JW, Choi YJ, You JY, Bae SY, Jung SP, Cho KR, Park KH. Incidence and risk factors for congestive heart failure in early breast cancer received anthracycline and/or trastuzumab; big-data analysis of Korean health insurance review and assessment service database [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-09.

Airway management using a supraglottic airway device without endotracheal intubation for positive ventilation of anaesthetized rats

Endotracheal intubation is often necessary for positive pressure ventilation of rats during open thoracic surgery. Since endotracheal intubation in rats is technically difficult and is associated with numerous complications, many techniques using various devices have been described in the scientific literature. In this study, we compared the effectiveness of airway management of a home-made supraglottic airway device (SAD), which is cheap to fabricate and easy to place with that of an endotracheal intubation tube in enflurane-anaesthetized rats. Twenty male Sprague-Dawley rats (200-300 g) were randomly assigned to two equal groups for positive pressure mechanical ventilation using either the SAD or an endotracheal intubation tube. The carotid artery of each rat was cannulated for continuous blood pressure measurements and obtaining blood samples for determination of oxygen tension, carbon dioxide tension, and blood acidity before, during and after SAD placement or endotracheal intubation. Proper placement of the SAD was confirmed by observing chest wall movements that coincided with the operation of the mechanical ventilator. No complications and adverse events were encountered in the rats in which the SAD was placed, during SAD placement and immediate removal, during their mechanical ventilation through the SAD, and one week after SAD removal. From the results of blood gas analyses, we conclude that anaesthetized rats can be successfully ventilated using an SAD for open thoracic surgery.

Intramyocardial transfer of hepatocyte growth factor as an adjunct to CABG: phase I clinical study

The purpose of this phase I clinical trial was to evaluate the safety, tolerability and potential efficacy of VM202, naked DNA expressing two isoforms of hepatocyte growth factor, as an adjunct therapy to coronary artery bypass grafting (CABG) in patients with ischemic heart disease (IHD). Nine patients were assigned to receive increasing doses (0.5 to 2.0 mg) of VM202 injected into the right coronary artery (RCA) territory following completion of CABG for the left coronary artery territory. Patients were evaluated for safety and tolerability, and changes in myocardial functions were monitored via echocardiography, cardiac magnetic resonance imaging and myocardial single photon emission computed tomography throughout 6-month follow-up period. No serious complication related to VM202 was observed throughout the 6-month follow-up period. Global myocardial functions (wall motion score index, P=0.0084; stress perfusion, P=0.0002) improved during the follow-up period. In the RCA region, there was an increase in the stress perfusion (baseline vs 3-month, P=0.024; baseline vs 6-month, P=0.024) and also in the wall thickness of the diastolic and systolic phases. Intramyocardial injection of VM202 can be safely used in IHD patients with the tolerable dose of 2.0 mg. In addition, VM202 might appear to have improved regional myocardial perfusion and wall thickness in the injected region.

P1-01-07: ErbB-2 Peptide Vaccination Suppresses Spontaneous Tumorigenesis and Tumor Stem Cell Expansion in MMTV-PyVT Transgenic Mouse

Immunization targeting ErbB-2 could have considerable therapeutic potential by controlling growth and metastasis of highly aggressive tumor cells in the earlier preclinical and clinical studies. Just a few studies have examined preventive potential of ErbB-2 vaccines in preclinical studies. However, animal model systems used in the previous studies were tumor transplantation or neu-transgenic mouse, which were not relevant to human HER-2 positive breast tumorigenesis. In this study, active immunotherapy against tumor antigen ErbB-2/neu for primary prevention of breast cancer was tested using FVB/N-Tg (MMTV-PyVT) transgenic mice model. Mice were grouped to receive either ErbB-2 peptide vaccine, immune adjuvant only, tetanus toxoid, or PBS every 2 weeks for 3 times and monthly thereafter. The MMTV-PyVT transgenic mice in control groups (PBS, immune adjuvant only, or tetanus toxoid peptide) developed spontaneous mammary adenocarcinomas in 12 to 15 weeks, but vaccination against ErbB-2 strongly suppressed tumor formation by 30 weeks of observation. Further pathologic examination showed complete prevention of tumorigenesis was observed in ErbB-2 vaccinated mice, whereas the mice in control groups developed highly aggressive ErbB-2 overexpressing tumors similar to human breast cancer. The tumor protective effect of peptide vaccination was associated with induction of ErbB-2-specific humoral immune responses as well as T cell responses. Additionally, role of signal through ErbB-2 pathway and the relationship with stemness of cancer cells were determined by Aldefluor assay, mammosphere formation assay using Mouse mammary carcinoma (MMC) cells in vitro, and level of nestin expression determined by Western blot analysis. Further analysis of mammosphere formation capacity of MMC cells using immune sera showed that sera from ErbB2 vaccinated mice had a significant inhibitory effect on mammosphere formation in ErbB-2 overexpressing MMC cells. These results suggest that ErbB-2 targeting by cancer vaccination might be useful adjuvant to standard therapy, helping to prevent relapse in patients with ErbB-2-overexpressing tumors by suppressing stem/progenitor cell population.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-01-07.

Lung injury induced by the pulmonary instillation of povidone-iodine in rats

PURPOSE

Povidone-iodine (polyvinylpyrrolidone iodine, PI), which is commonly used as a pre- and postoperative oral antiseptic, has been reported to cause pneumonia secondary to its pulmonary aspiration. Because no studies have yet investigated the underlying mechanisms of PI-induced pneumonia, we conducted an animal study to analyze the effect of PI on the lung following its pulmonary instillation.

METHODS

The lungs of 61 male Sprague-Dawley rats (150-250 g) were instilled with varying volumes of either phosphate-buffered saline or PI solutions varying in strength from 0.01% to 10%. The lungs were harvested from the rats 1 h or 1, 3, 5, 7, 14, or 21 days after instillation for radiologic examination, macroscopic and light and scanning electron microscopic assessment, and an assessment of pulmonary toxicity using an MTT-based cytotoxicity assay.

RESULTS

Macroscopically, atelectasis was the primary pulmonary lesion after PI instillation. The primary light and scanning electron microscopic findings were an initial inflammatory phase with edema, alveolar rupture, and leukocyte infiltration into the pulmonary interstitium, which progressed into a phase of lung parenchyma loss, and then resolved itself with scar tissue formation. Lung tissue viability following 1-day exposure to 0.01%, 0.1%, 1%, or 5% PI progressively decreased in a significant dose-dependent manner.

CONCLUSIONS

PI aspiration can cause lung injury, including pulmonary fibrosis.

May-Thurner syndrome found incidentally after left femoral catheterization in a pediatric patient

In May-Thurner syndrome, the left common iliac vein is compressed between the overlying right common iliac artery and the underlying vertebral body. Chronic and/or repetitive compressions at this site cause fibrosis of the vein and thus stenosis, potentially occluding the lumen. This report describes a case of May-Thurner syndrome discovered incidentally after femoral catheterization for chemotherapy in a 25-month-old child with juvenile myelomonocytic leukemia (JMML). The patient had no symptoms associated with compression. The syndrome was diagnosed by computed tomography, and there was no evidence of thrombosis. The patient died secondary to sepsis.

Prevention of pain during injection of microemulsion propofol: application of lidocaine mixture and the optimal dose of lidocaine

Background

Similar to lipid emulsion propofol, microemulsion propofol also causes a high incidence of pain during intravenous injection. Various methods have been used to minimize the incidence and severity of pain on injection of lipid emulsion propofol. In this study, we investigated the effect of a lidocaine mixture on pain induced by microemulsion propofol injection, and sought to determine the optimal dose of lidocaine that could reduce pain on injecting a propofol-lidocaine mixture.

Methods

One hundred sixty (n = 160) patients of American Society of Anesthesiologists physical status class I or II were randomly allocated to four groups: Group A, control; Group B, 20 mg lidocaine; Group C, 30 mg lidocaine; Group D, 40 mg lidocaine. In each patient, pain on microemulsion propofol solution injection was graded as none, mild, moderate, or severe.

Results

The incidence of pain in groups A, B, C, and D was 97.5%, 80%, 65%, and 50%, respectively. Increasing the lidocaine dose significantly reduced pain (P < 0.05). One patient in Group D (2.5%) had moderate to severe pain, which was significantly lower than groups B (42.5%) and C (32.5%) (P < 0.05).

Conclusions

The lidocaine and propofol mixture is effective in alleviating pain associated with microemulsion propofol injection. Within this dose range and in this patients population, increasing lidocaine dosage significantly reduced pain during injection of microemulsion propofol.

The effect of propofol on emergence agitation in children receiving sevoflurane for adenotonsillectomy

BACKGROUND

The administration of a single dose of propofol is reported to be effective in decreasing the incidence and severity of emergence agitation (EA) in children following sevoflurane anesthesia. The aim of this study was to investigate the clinical usefulness of a single dose of propofol 1 mg/kg at the end of adenotonsillectomy for reducing the incidence of EA after sevoflurane anesthesia.

METHODS

Ninety children, aged 3-8 years, undergoing adenotonsillectomy were randomized into two groups: the propofol group (n = 45) and the saline group (n = 45), of which 88 children completed the study. Anesthesia was maintained with sevoflurane 2-2.5 vol% and nitrous oxide/oxygen (50%/50%). At the completion of adenotonsillectomy, the propofol group patients were given 1 mg/kg of propofol and the saline group patients were given saline 0.1 ml/kg in the same volume. The incidence of EA was assessed with Aono's four point scale and the severity of EA was assessed with pediatric anesthesia emergence delirium (PAED) scale at 5 min (T5), 15 min (T15) and 30 min (T30) after emergence.

RESULTS

Of the 88 patients, the incidence of EA at T5, T15 and T30 was 61.4%, 27.3%, and 4.5% in the propofol group while in the saline group was 68.2%, 29.5%, and 9.1%, respectively. The incidence and severity of EA were not found to be significantly different between the two groups, but the scales in each group decreased significantly over time.

CONCLUSIONS

The administration of propofol 1 mg/kg at the end of surgery did not have any significant effect in reducing the incidence and severity of EA in children undergoing adenotonsillectomy under sevoflurane anesthesia.

Lambert-Eaton myasthenic syndrome as a cause of persistent neuromuscular weakness after a mediastinoscopic biopsy -A case report-

There are many causes of prolonged postoperative muscle weakness, including drugs, residual anesthetics, cerebrovascular events, electrolyte imbalance, hypothermia, and neuromuscular disease. Neuromuscular diseases are relatively rare, with the most common being myasthenia gravis and Lambert-Eaton myasthenic syndrome (LEMS). We report an unusual case in which a patient who was given a muscle relaxant during mediastinoscopy developed postoperative muscle weakness that was ultimately diagnosed as secondary to LEMS.

Inter-arm arterial pressure difference caused by prone position in the thoracic outlet syndrome patient -A case report-

Thoracic outlet syndrome has neurologic symptoms caused by compression of brachial plexus, blood vessel symptoms are caused by compression of the artery or vein. The authors report a case of sudden decrease in blood pressure of the left arm after turning the patient from supine position to prone position. They confirmed that the patient had thoracic outlet syndrome after performing computed tomography.

Comparison of the effects of acetaminophen to ketorolac when added to lidocaine for intravenous regional anesthesia

BACKGROUND

This study was done to evaluate the effect on pain relief when acetaminophen was added to lidocaine for intravenous regional anesthesia (IVRA).

METHODS

SIXTY PATIENTS UNDERGOING HAND OR FOREARM SURGERY RECEIVED IVRA WERE ASSIGNED TO THREE GROUPS: Group C received 0.5% lidocaine diluted with 0.9% normal saline to a total volume of 40 ml (n = 20), Group P received 0.5% lidocaine diluted with intravenous acetaminophen 300 mg to a total volume of 40 ml (n = 20) and Group K received 0.5% lidocaine diluted with 0.9% normal saline plus ketorolac 10 mg made up to a total volume of 40 ml (n = 20). Sensory block onset time, tourniquet pain onset time, which was defined as the time from tourniquet application to fentanyl administration for relieving tourniquet pain and amount of analgesic consumption during surgery were recorded. Following deflation of tourniquet sensory recovery time, postoperative pain and quantity of analgesic uses in post-anesthesia care unit were assessed.

RESULTS

Sensory block onset time was shorter in Group P compared to Group C (P < 0.05). Tourniquet pain onset time was delayed in Group P when compared with group C (P < 0.05). Postoperative pain and analgesic consumption were reduced in Group P and Group K compared to Group C (P < 0.001).

CONCLUSIONS

The addition of acetaminophen to lidocaine for IVRA shortens the onset time of sensory block and delays tourniquet pain onset time, but not with ketorolac. Both acetaminophen and ketorolac reduce postoperative pain and analgesic consumption.

Unilateral administration of a drug into the lung of a small animal

Background

The selective unilateral administration of drugs into a single lung of a rat is difficult because of the small airway diameter. Therefore, a simple method for unilateral administration into rat lung is needed.

Methods

Rats were assigned to 1 of 2 groups according to the direction of the catheter used for drug administration. Anesthetized rats were intubated, and curved epidural catheters were rotated up to a maximum of 90° toward the left lung (group L) or right lung (group R). Bronchial catheters were then inserted via a tracheal tube and fixed. Methylene blue (0.3 ml) was injected via the epidural catheter. Additionally, to compare survival rates, rats were assigned to one of two groups according to the drug administration route. In group T, bleomycin hydrochloride (20 mg/kg) in 0.3 ml of phosphate-buffered saline (PBS) was administrated into the lung intratracheally via a tracheal tube. In group B, the same dose of bleomycin was administrated into the lung intrabronchially via a bronchial catheter, targeting the left lung.

Results

Gross examination revealed that targeted administration was 100% successful. Methylene blue was observed in the right lung of all rats in the R group and in the left lung of all rats in the L group. The survival rate was higher in group B than in group T.

Conclusions

The intrabronchial method offers an advantage over tracheal administration as it decreases mortality and allows the administration of a drug unilaterally into a single lung or into a localized area without the need for double-lumen tubes or more invasive procedures.

The effects of hemodilution on acute inflammatory responses in a bleomycin-induced lung injury model

Acute normovolemic hemodilution (ANH) can be used in acute lung injury (ALI) patients who refuse blood transfusions. To investigate the effects of hemodilution on the acute inflammatory response in lung injury, the authors studied the effects of ANH in a rat model of bleomycin-induced lung injury. Bleomycin (10 mg/kg) was used to induce lung injury in 2 groups of rats. The treatment groups included a lung injury group with hemodilution (HI), a lung injury group without hemodilution (NHI), and a control group. Hemodilution was performed by removing blood and substituting the same amount of hydroxyethyl starch solution targeted to 7.0 g/dL via the right and left internal jugular veins. At day 3 after bleomycin instillation, systemic hemoglobin concentration was 9.5 +/- 1.1 g/dL. Tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6 levels measured in the bronchoalveolar lavage fluid (BALF), blood, and lung tissue were not significantly different between the HI and NHI groups 3 days after lung injury. Microscopic findings showed fibrosis and inflammation in the HI and NHI groups 28 days after lung injury, but no significant differences were found between the 2 groups. Hemodilution after bleomycin administration did not further affect the acute inflammatory response or lung injury.

Uncontrollable hyperthermia in acute cerebral injury: A case report

A 39 year old man arrived at the hospital with semi-comatose state as a result of spontaneous intracerebral hemorrhage (ICH), intraventricular hemorrhage (IVH) and subarachnoid hemorrhage (SAH). For emergency craniectomy and hematoma removal, general anesthesia with desflurane and vecuronium was planned. Before the induction of anesthesia, the body temperature and end-tidal carbon dioxide (ETCO2) levels were 38.3degrees C and 38 mmHg, respectively. The body temperature and ETCO2 increased during surgery. After 2 hours of anesthesia, the temperature had increased to 41degrees C, despite bladder irrigation and body cooling. After 3 hours of anesthesia, the temperature reached 43.5degrees C and cardiac arrest developed. Cardiopulmonary resuscitation was attempted, but the patient expired.

Predictive value of C-reactive protein for major postoperative complications following off-pump coronary artery bypass surgery: prospective and observational trial

BACKGROUND

To prospectively investigate the predictive value of the preoperative C-reactive protein (CRP) concentration for major postoperative complications following off-pump coronary artery bypass (OPCAB) surgery.

METHODS AND RESULTS

From January 2007 to December 2007, 185 consecutive patients scheduled for elective OPCAB surgery were allocated to a low-CRP group (n=137, CRP <0.3 mg/dl) and a high-CRP group (n=48, CRP > or = 0.3 mg/dl). The incidence of major postoperative complications, defined as postoperative myocardial infarction, and 5 major morbidity endpoints including permanent stroke, renal dysfunction, any cardiac surgery reoperation, ventilation for more than 48 h, and deep sternal wound infection were assessed and compared. Multivariate logistic regression was used to determine the predictors of major postoperative complications. Patients in the high-CRP group had a significantly higher overall incidence of major postoperative complications, particularly renal dysfunction. In the multivariate logistic regression model, adjusting all the significant univariate predictors, baseline CRP >0.3 mg/dl and preoperative chronic renal failure (CRF) remained as significant independent predictors of major postoperative complications.

CONCLUSIONS

Elevated preoperative CRP level and/or preoperative CRF indicate increased risk of developing major postoperative complications, particularly acute postoperative renal dysfunction in patients undergoing OPCAB surgery.

Cell adhesion molecules as tumour suppressors

Cell adhesion molecules, a diverse group of proteins expressed on the cell surface, have been implicated in numerous important cellular functions ranging from controlling morphogenesis to suppressing tumourigenesis. In this article, we discuss evidence supporting the idea that at least some proteins involved in cell adhesion may suppress tumourigenesis through influences on cell growth, differentiation and/or invasion. These studies suggest that some cell adhesion molecules may be encoded by tumour suppressor genes.

Loss of CDX2 expression and microsatellite instability are prominent features of large cell minimally differentiated carcinomas of the colon

Most large bowel cancers are moderately to well-differentiated adenocarcinomas comprised chiefly or entirely of glands lined by tall columnar cells. We have identified a subset of poorly differentiated colon carcinomas with a distinctive histopathological appearance that we term large cell minimally differentiated carcinomas (LCMDCs). These tumors likely include a group of poorly differentiated carcinomas previously described by others as medullary adenocarcinomas. To better understand the pathogenesis of these uncommon neoplasms, we compared molecular features of 15 LCMDCs to those present in 25 differentiated adenocarcinomas (DACs) of the colon. Tumors were examined for alterations commonly seen in typical colorectal carcinomas, including increased p53 and beta-catenin immunoreactivity, K-ras gene mutations, microsatellite instability, and loss of heterozygosity of markers on chromosomes 5q, 17p, and 18q. In addition, tumors were evaluated by immunohistochemistry for CDX2, a homeobox protein whose expression in normal adult tissues is restricted to intestinal and colonic epithelium. Markedly reduced or absent CDX2 expression was noted in 13 of 15 (87%) LCMDCs, whereas only 1 of the 25 (4%) DACs showed reduced CDX2 expression (P < 0.001). Nine of 15 (60%) LCMDCs had the high-frequency microsatellite instability phenotype, but only 2 of 25 (8%) DACs had the high-frequency microsatellite instability phenotype (P = 0.002). Our findings provide support for the hypothesis that the molecular pathogenesis of LCMDCs is distinct from that of most DACs. CDX2 alterations and DNA mismatch repair defects have particularly prominent roles in the development of LCMDCs.

Diverse mechanisms of beta-catenin deregulation in ovarian endometrioid adenocarcinomas

Clinical and molecular findings suggest that the four major histological subtypes of ovarian carcinoma (serous, clear cell, mucinous, and endometrioid) likely represent distinct disease entities. Prior studies have shown that ovarian endometrioid adenocarcinomas (OEAs) often carry mutations in the CTNNB1 gene, which encodes beta-catenin, a critical component of the Wnt signaling pathway. However, the nature of other defects in the Wnt signaling pathway in ovarian carcinomas remains largely unknown. Thus, in 45 primary OEAs and two OEA-derived cell lines, we sought to comprehensively address the prevalence of and mechanisms underlying beta-catenin and Wnt pathway deregulation. CTNNB1 missense mutations were detected in 14 primary tumors. All mutations affected the NH(2)-terminal regulatory domain of beta-catenin, presumably rendering the mutant proteins resistant to degradation. Immunohistochemical studies revealed nuclear accumulation of beta-catenin in all but two tumors with CTNNB1 mutations. Two primary tumors lacking CTNNBI mutations showed strong nuclear immunoreactivity for beta-catenin. In one of the two tumors, biallelic inactivation of the APC gene was found. In the remaining 29 primary OEAs, unequivocal nuclear beta-catenin immunoreactivity was not observed, though a nonsense mutation in AXIN1 was observed in one tumor and a truncating frameshift mutation in AXIN2 was seen in another case. Both OEA-derived cell lines studied (TOV-112D and MDAH-2774) had elevated constitutive T-cell factor/lymphoid enhancer factor transcriptional activity. TOV-112D cells were shown to harbor mutant beta-catenin, whereas a missense AXIN1 sequence alteration was identified in MDAH-2774 cells. Collectively, our findings demonstrate frequent defects of the Wnt signaling pathway in a particular subtype of ovarian carcinomas, i.e., OEAs. Although mutations in the CTNNB1 gene are the most common mechanism of beta-catenin deregulation in OEAs, beta-catenin deregulation may also result from mutations in the APC, AXIN1, and AXIN2 genes.

Glial implants in gliomatosis peritonei arise from normal tissue, not from the associated teratoma

Metaplasia of subcoelomic mesenchyme has been implicated, but not proven, in the pathogenesis of common gynecological diseases such as endometriosis and rarer entities such as leiomyomatosis peritonealis disseminata and gliomatosis peritonei (GP). GP is associated with ovarian teratomas and is characterized by numerous peritoneal and omental implants composed of glial tissue. Two theories to explain the origin of GP have been proposed. In one, glial implants arise from the teratoma, whereas in the other, pluripotent Müllerian stem cells in the peritoneum or subjacent mesenchyme undergo glial metaplasia. To address the origin of GP, we exploited a unique characteristic of many ovarian teratomas: they often contain a duplicated set of maternal chromosomes and are thus homozygous at polymorphic microsatellite (MS) loci. In contrast, DNA from matched normal or metaplastic tissue (containing genetic material of both maternal and paternal origin) is expected to show heterozygosity at many of these same MS loci. DNA samples extracted from paraffin-embedded normal tissue, ovarian teratoma and three individual laser-dissected glial implants were studied in two cases of GP. In one case, all three implants and normal tissue showed heterozygosity at each of three MS loci on different chromosomes, whereas the teratoma showed homozygosity at the same MS loci. Similar results were observed in the second case. Our findings indicate that glial implants in GP often arise from cells within the peritoneum, presumably pluripotent Müllerian stem cells, and not from the associated ovarian teratoma. This finding has important implications for more common gynecological entities with debatable pathogenesis, such as endometriosis, by definitively demonstrating the metaplastic potential of stem cells within the peritoneal cavity.

Coordinately up-regulated genes in ovarian cancer

A better understanding of the molecular circuitry in normal ovarian tissues and in ovarian cancer will likely provide new targets for diagnosis and therapy. Recently, much has been learned about the genes expressed in ovarian cancer through studies with cDNA arrays and serial analysis of gene expression. However, these methods do not allow highly quantitative analysis of gene expression on a large number of specimens. Here, we have used quantitative real-time RT-PCR in a panel of 39 microdissected ovarian carcinomas of various subtypes to systematically analyze the expression of 13 genes, many of which were previously identified as up-regulated in a subset of ovarian cancers by serial analyses of gene expression. The genes analyzed are glutathione peroxidase 3 (GPX3), apolipoprotein J/clusterin, insulin-like growth factor-binding protein 2, epithelial cell adhesion molecule/GA733-2, Kop protease inhibitor, matrix gla protein, tissue inhibitor of metalloproteinase 3, folate receptor 1, S100A2, signal transducer and activator of transcription 1, secretory leukocyte protease inhibitor, apolipoprotein E, and ceruloplasmin. All of the genes were found overexpressed, some at extremely high levels, in the vast majority of ovarian carcinomas irrespective of the subtype. Interestingly, GPX3 was found at much higher levels in tumors with clear cell histology and may represent a biomarker for this subtype. Some of the genes studied here may thus represent targets for early detection ovarian cancer. The gene expression patterns were not associated with age at diagnosis, stage, or K-ras mutation status in ovarian cancer. We find that several genes are coordinately regulated in ovarian cancer, likely representing the fact that many genes are activated as part of common signaling pathways or that extensive cross-talk exists between several pathways in ovarian cancer. A statistical analysis shows that genes commonly up-regulated in ovarian cancer may result from the aberrant activation of a limited number of pathways, providing promising targets for novel therapeutic strategies.

Somatic mutations of fibroblast growth factor receptor 3 (FGFR3) are uncommon in carcinomas of the uterine cervix

Germline mutations of the gene encoding human fibroblast growth factor receptor 3 (FGFR3) have been shown to be responsible for several related autosomal dominant forms of syndromic craniosynostosis and short limb dwarfism. Somatic activating mutations of FGFR3 were recently reported to occur in three of 12 (25%) uterine cervical carcinomas and nine of 26 (35%) bladder carcinomas, suggesting that constitutive activation of FGFR3 may be an important mechanism underlying the development and/or progression of these common epithelial malignancies. In order to investigate further a possible role for FGFR3 mutations in cervical carcinogenesis, we performed sequence-based mutational analysis of FGFR3 in 51 primary cervical carcinomas and seven cervical carcinoma-derived cell lines. The regions analysed (exons 7, 10, 13, 15, and 19) encompassed all previously described FGFR3 mutations. A single nucleotide substitution at codon 249, predicting a serine to cysteine amino acid substitution (S249C) in the FGFR3 extracellular domain, was identified in one primary tumor. Only wild type FGFR3 alleles were identified in the remaining tumors and cell lines. The S249C mutation is the only FGFR3 mutation described to date in cervical carcinomas. These findings suggest that while activating mutations of FGFR3 occur in cervical cancer, they may not be as common as initially reported.

Large-scale serial analysis of gene expression reveals genes differentially expressed in ovarian cancer

Difficulties in the detection, diagnosis, and treatment of ovarian cancer result in an overall low survival rate of women with this disease. A better understanding of the pathways involved in ovarian tumorigenesis will likely provide new targets for early and effective intervention. Here, we have used serial analysis of gene expression (SAGE) to generate global gene expression profiles from various ovarian cell lines and tissues, including primary cancers, ovarian surface epithelia cells, and cystadenoma cells. The profiles were used to compare overall patterns of gene expression and to identify differentially expressed genes. We have sequenced a total of 385,000 tags, yielding >56,000 genes expressed in 10 different libraries derived from ovarian tissues. In general, ovarian cancer cell lines showed relatively high levels of similarity to libraries from other cancer cell lines, regardless of the tissue of origin (ovarian or colon), indicating that these lines had lost many of their tissue-specific expression patterns. In contrast, immortalized ovarian surface epithelia and ovarian cystadenoma cells showed much higher similarity to primary ovarian carcinomas than to primary colon carcinomas. Primary tissue specimens therefore appeared to be a better model for gene expression analyses. Using the expression profiles described above and stringent selection criteria, we have identified a number of genes highly differentially expressed between nontransformed ovarian epithelia and ovarian carcinomas. Some of the genes identified are already known to be overexpressed in ovarian cancer, but several represent novel candidates. Many of the genes up-regulated in ovarian cancer represent surface or secreted proteins such as claudin-3 and -4, HE4, mucin-1, epithelial cellular adhesion molecule, and mesothelin. Interestingly, both apolipoprotein E (ApoE) and ApoJ, two proteins involved in lipid homeostasis, are among the genes highly up-regulated in ovarian cancer. Selected serial analysis of gene expression results were further validated through immunohistochemical analysis of ApoJ, claudin-3, claudin-4, and epithelial cellular adhesion molecule in archival material. These experiments provided additional evidence of the relevance of our findings in vivo. The publicly available expression data reported here should stimulate and aid further research in the field of ovarian cancer.

Loss of fhit expression in invasive cervical carcinomas and intraepithelial lesions associated with invasive disease

Allelic losses involving chromosome 3p are frequently observed in cervical cancers. Deletion mapping studies of primary cervical carcinomas have localized common regions of deletion to 3p14.2 and 3p21. The candidate tumor suppressor gene FHIT has been mapped to 3p14.2, and previous studies have demonstrated reduced or aberrant FHIT transcripts and reduced or absent Fhit protein expression in a large percentage of cervical cancer-derived cell lines and primary cervical carcinomas. To expand these observations to preinvasive cervical epithelial lesions and to determine whether loss of Fhit protein expression might be associated with tumor progression, immunohistochemical methods were used to examine Fhit expression in 95 invasive cervical carcinomas, 33 high-grade squamous intraepithelial lesions (HSILs) associated with concurrent invasive cancer, 38 HSILs unassociated with invasive cancer, 24 low-grade squamous intraepithelial lesions, and 22 normal cervix samples. All normal cervical epithelia and low-grade squamous intraepithelial lesions exhibited diffuse cytoplasmic immunostaining of moderate to strong intensity. Fhit protein expression was markedly reduced or absent in 67 of 95 (71%) invasive cancers, 17 of 33 (52%) HSILs associated with invasive cancer, and 8 of 38 (21%) HSILs without associated invasive cancer. The results confirm that Fhit protein expression is reduced or absent in the majority of cervical carcinomas and suggest that loss of Fhit expression often accompanies cervical tumor progression. Moreover, absent or reduced Fhit protein is observed at a significantly higher frequency in HSILs associated with progression to invasive cancer than in HSILs with unknown risk for progression (P = 0.012). These findings suggest that loss of Fhit expression in HSILs could serve as a useful marker of high-grade preinvasive lesions that have an increased likelihood of progression to invasive carcinoma.

gamma-catenin is regulated by the APC tumor suppressor and its oncogenic activity is distinct from that of beta-catenin

beta-Catenin and gamma-catenin (plakoglobin), vertebrate homologs of Drosophila armadillo, function in cell adhesion and the Wnt signaling pathway. In colon and other cancers, mutations in the APC tumor suppressor protein or beta-catenin's amino terminus stabilize beta-catenin, enhancing its ability to activate transcription of Tcf/Lef target genes. Though beta- and gamma-catenin have analogous structures and functions and like binding to APC, evidence that gamma-catenin has an important role in cancer has been lacking. We report here that APC regulates both beta- and gamma-catenin and gamma-catenin functions as an oncogene. In contrast to beta-catenin, for which only amino-terminal mutated forms transform RK3E epithelial cells, wild-type and several amino-terminal mutated forms of gamma-catenin had similar transforming activity. gamma-Catenin's transforming activity, like beta-catenin's, was dependent on Tcf/Lef function. However, in contrast to beta-catenin, gamma-catenin strongly activated c-Myc expression and c-Myc function was crucial for gamma-catenin transformation. Our findings suggest APC mutations alter regulation of both beta- and gamma-catenin, perhaps explaining why the frequency of APC mutations in colon cancer far exceeds that of beta-catenin mutations. Elevated c-Myc expression in cancers with APC defects may be due to altered regulation of both beta- and gamma-catenin. Furthermore, the data imply beta- and gamma-catenin may have distinct roles in Wnt signaling and cancer via differential effects on downstream target genes.

Restored expression of fragile histidine triad protein and tumorigenicity of cervical carcinoma cells

BACKGROUND

Allelic losses in the short arm of chromosome 3 are common in cervical carcinomas. The fragile histidine triad (FHIT) gene at chromosome region 3p14.2 is a candidate tumor suppressor gene that may play a role in cervical tumorigenesis. We and others have identified aberrant FHIT transcripts and frequent loss of Fhit protein expression in primary cervical cancers and high-grade noninvasive lesions but not in normal cervical tissues. The altered expression of FHIT may be due to somatic mutations or integration of human papillomavirus DNA at the FHIT locus. The purpose of this study was to determine whether ectopic expression of Fhit can suppress the tumorigenic properties of cervical cancer cells.

METHODS

We employed infection with recombinant retroviruses as well as transfection of plasmid DNA to restore Fhit protein expression in cervical cancer cell lines lacking full-length FHIT transcripts and endogenous Fhit protein. The effects of Fhit expression on tumor cell morphology, anchorage-independent growth, and tumorigenicity in nude mice were examined.

RESULTS

Stable overexpression of Fhit had no discernible effect on the tumorigenic properties of two cervical carcinoma cell lines or on a lung carcinoma cell line previously reported by others to be suppressed for tumorigenicity by Fhit.

CONCLUSIONS

Restoration of Fhit expression does not suppress anchorage-independent growth or tumorigenicity of cervical carcinoma cell lines. However, it remains possible that FHIT inactivation may be important early in cervical tumor progression or that FHIT may suppress tumorigenesis in ways distinct from those measured by the assays employed in this study.

Somatic mutations in the STK11/LKB1 gene are uncommon in rare gynecological tumor types associated with Peutz-Jegher's syndrome

Peutz-Jegher's syndrome (PJS) is a rare autosomal dominant disorder characterized by mucocutaneous pigmentation, hamartomatous polyposis, and predisposition to benign and malignant tumors of the gastrointestinal tract, breast, ovary, uterine cervix, and testis. Germline-inactivating mutations in one allele of the STK11/LKB1 gene at chromosome 19p13.3 have been found in most PJS patients. Although ovarian sex cord tumors with annular tubules (SCTATs) and minimal deviation adenocarcinomas (MDAs) of the uterine cervix are very rare in the general population, both tumor types occur with increased frequency in women with PJS. An earlier report indicated that the 19p13.3 region containing the STK11 gene was affected by loss of heterozygosity (LOH) in nearly 50% of MDAs of the uterine cervix. We investigated the role of STK11 mutations and LOH of the 19p13.3 region in two PJS-associated SCTATs and in five SCTATs and eight MDAs of the uterine cervix, which occurred in patients lacking features of PJS (referred to here as "sporadic" cases). Germline mutations in the STK11 gene, accompanied by LOH of markers near the wild-type STK11 allele, were found in the two PJS-associated SCTATs. Somatic mutations in the coding region of STK11 were not found in any of the sporadic SCTATs or MDAs studied, although LOH of the 19p13.3 region was seen in three of eight MDAs. Our findings indicate that STK11, like other tumor suppressor genes, is affected by biallelic inactivation in gynecological tumors of PJS patients. In addition, although LOH of the 19p13.3 region was seen in sporadic MDAs, somatic STK11 mutations are rare. A yet-to-be-defined tumor suppressor gene in the 19p13.3 region may be the specific target of inactivation in these tumors.

Neural toxicity induced by accidental intrathecal vincristine administration

Described here is a case of accidental intrathecal administration of vincristine with pathologic findings in the central nervous system. A 3-year-old boy with acute lymphoblastic leukemia, was given his ninth course chemotherapy. Vincristine was accidentally injected intrathecally. The clinical course was rapidly progressive (6-day course) and resulted in death. An autopsy was done. The brain and spinal cord was grossly edematous and congested without any specific feature. Histologically, profound loss of neuron was noted in the spinal cord. Remaining neurons in the spinal cord, particularly anterior horn cells were markedly swollen. The spinal nerves show diffuse axonal degeneration and myelin loss. The upstream portion of the spinal cord (brain stem, cerebellum, cerebrum) showed patchy loss of neurons, especially Purkinje cells and granular cells of the cerebellar cortex. Many neurons showed axonal reaction (chromatolysis) with swelling. Several neurons show intracytoplasmic eosinophilic inclusion body. Myelin loss, axonal swelling and enlargement of perivascular spaces were seen throughout the white matter of central nervous system.

Somatic mutations of the PPP2R1B candidate tumor suppressor gene at chromosome 11q23 are infrequent in ovarian carcinomas

Previous studies have demonstrated frequent allelic losses of distal chromosome 11q in ovarian carcinomas. The tumor suppressor gene(s) presumably targeted by these losses have not yet been identified. PPP2R1B is a candidate tumor suppressor gene at 11q23 that has recently been shown to be mutated in a subset of colorectal and lung cancers. We evaluated 5 ovarian carcinoma cell lines and 27 primary ovarian carcinomas for allelic losses of 11q23 and for mutations in the open reading frame of PPP2R1B. We also evaluated the primary tumors for allelic losses at 17p13, another chromosomal region frequently affected by losses of heterozygosity (LOH) in ovarian cancers. 11q23 and 17p13 allelic losses were identified in 25% and 74% of the carcinomas, respectively. No mutations within PPP2R1B coding sequences were found. These findings indicate that mutations of the PPP2R1B gene are infrequent in ovarian cancer and that deletions affecting the distal portion of chromosome 11q in ovarian cancer likely target inactivation of other genes.

The Cox-Maze III procedure for atrial fibrillation associated with rheumatic mitral valve disease

BACKGROUND

The surgical results of the Cox-Maze III procedure (CM-III) for atrial fibrillation (AF) associated with rheumatic mitral valve (MV) disease are not as good as the results from surgery for AF alone.

METHODS

To assess the efficacy and safety of the CM-III in AF associated with rheumatic MV disease, we retrospectively analyzed 75 patients who underwent the CM-III combined with a rheumatic MV procedure between April 1994 and December 1997. Fourteen cases were reoperations because of prosthetic valve failure.

RESULTS

Mean aortic cross-clamp (ACC) times and cardiopulmonary bypass (CPB) times were 151+/-43 and 251+/-73 min, respectively. Concomitant procedures were mitral valve replacement (MVR) in 25 patients, MVR and aortic valve replacement (AVR) in 14 patients, MV repair in 10 patients, MVR and tricuspid annuloplasty (TAP) in 6 patients, MVR and AV repair in 3 patients, MVR and coronary artery bypass grafting (CABG) in 2 patients, MVR and AVR and CABG in 1 patient, redo-MVR in 8 patients, redo-MVR and TAP in 4 patients, and redo-MVR and redo-AVR in 2 patients. There were two in-hospital mortalities (2 of 75, 2.7%). Seventy-three survivors were followed for a mean duration of 30+/-13 months (12-56 months). Normal sinus rhythm was restored in 90.4% (66 of 73). Three patients remained in AF and 2 patients were in junctional rhythm. Permanent pacemakers were implanted in 2 patients due to sick sinus syndrome. Right atrial (RA) contractility was demonstrable in 100% (66 of 66) and left atrial (LA) contractility in 62.1% (41 of 66) of the patients in the latest follow-up echocardiography. RA and LA contractilities were restored a mean 69+/-93 and 126+/-136 days after the operation, respectively. LA contractility was restored significantly later at a lower rate than RA contractility in rheumatic MV disease. There were no differences in ACC time, CPB time, incidence of postoperative bleeding complications, and sinus conversion rates between non-redo and redo cases in spite of the significantly longer duration of preoperative AF in redo cases (p<0.05).

CONCLUSIONS

The CM-III for AF associated with rheumatic MV disease demonstrated a high sinus conversion rate with acceptable operative risk even in cases of reoperation.

Molecular genetic evidence supporting the clonality and appendiceal origin of Pseudomyxoma peritonei in women

Pseudomyxoma peritonei (PMP) is a poorly understood condition characterized by mucinous ascites and multifocal peritoneal mucinous tumors. Women with PMP often have mucinous tumors involving both the appendix and the ovaries. Several previous histopathological and immunohistochemical studies of PMP have suggested that most, if not all, cases of PMP in women are derived from mucinous adenomas of the appendix rather than from primary ovarian tumors. A few studies of the molecular genetics of PMP have been recently reported. However, these studies analyzed only a small number of cases and some included a heterogeneous group of mucinous tumors, including both benign and malignant appendiceal and ovarian tumors. We analyzed K-ras mutations and allelic losses of chromosomes 18q, 17p, 5q, and 6q in a substantial number of morphologically uniform cases of PMP with synchronous ovarian and appendiceal tumors as well as in appendiceal mucinous adenomas (MAs) and ovarian mucinous tumors of low malignant potential (MLMPs) unassociated with PMP. Each of the 16 PMP cases (100%) analyzed demonstrated identical K-ras mutations in the appendiceal adenoma and corresponding synchronous ovarian tumor. K-ras mutations were identified in 11 of 16 (69%) appendiceal MAs unassociated with PMP and in 12 of 16 (75%) ovarian MLMPs unassociated with PMP. Two PMP cases showed identical allelic losses in the matched ovarian and appendiceal tumors. A discordant pattern of allelic loss between the ovarian and appendiceal tumors at one or two of the loci tested was observed in six PMP cases. In all but one instance, LOH was observed in the ovarian tumor, whereas both alleles were retained in the matched appendiceal lesion, suggesting tumor progression in a secondary (metastatic) site. Our findings strongly support the conclusion that mucinous tumors involving the appendix and ovaries in women with PMP are clonal and derived from a single site, most likely the appendix.

Atypical immature metaplasia (AIM) of the cervix: is it related to high-grade squamous intraepithelial lesion (HSIL)?

Atypical immature metaplasia (AIM) is a poorly characterized cervical lesion with uncertain biological and clinical significance. AIM shares some, but not all, morphological features of squamous intraepithelial lesions (SILs). SILs are characterized by human papillomavirus (HPV) positivity and increased cellular proliferation, but these features have not been fully evaluated in AIM. Genomic DNA was extracted from 27 microdissected cervical biopsy specimens diagnosed as AIM. HPV DNA was detected by polymerase chain reaction (PCR), using two different sets of L1 gene consensus primers. HPV types were identified by sequence analysis of PCR products and comparison with published HPV sequences. The cell proliferation index was assessed by immunohistochemical staining for Ki-67 (MIB-1) antigen and expressed as the percentage of Ki-67-positive cells. Comparison groups included normal cervix (n = 10) and low-grade (LSILs, n = 19) and high-grade squamous intraepithelial lesions (HSILs, n = 11). Intermediate- or high-risk HPV DNA was detected in 67% (18 of 27) of AIM cases. Low-risk HPV DNA was not detected in any of the specimens. The Ki-67 index in AIM (mean, 33.0 +/- 20.3; median, 29) was comparable to that of LSILs (mean, 21.4 +/- 4.6; median, 21) and was significantly higher than that of normal cervix (mean, 11.0 +/- 2.1; median, 11) (P< .01) and lower than that of HSILs (mean, 60.4 +/- 13.2; median, 60) (P < .01). Of the cases with available follow-up, HPV-positive AIMs were significantly more likely to have a concurrent or subsequent diagnosis of typical HSIL (12 of 15, 80%) than HPV-negative AIMs (one of six, 45%) (P = .014). The wide range of Ki-67 indices and variable HPV status in AIM suggest that AIM represents a heterogeneous group of lesions including bona fide HSILs (high-risk HPV-positive, high Ki-67 index), antecedents (precursors?) of HSILs (high-risk HPV-positive, low to moderate Ki-67 index), and benign reactive conditions (HPV-negative, variable Ki-67 index). HPV testing may be useful in the assessment of atypical epithelial proliferations of the cervix for which a diagnosis of AIM is considered.

Reproducibility of the diagnosis of endometrial hyperplasia, atypical hyperplasia, and well-differentiated carcinoma

Many studies have attempted to identify histologic features that aid in the distinction of atypical hyperplasia (AH) from hyperplasia without atypia and well-differentiated endometrioid carcinoma, but few have evaluated the reproducibility of these diagnoses. Five pathologists independently reviewed 100 endometrial biopsy and curettage specimens chosen to represent the entire spectrum of proliferative lesions of the endometrium, including proliferative endometrium (PEM), hyperplasia without atypia, AH, and well-differentiated endometrioid carcinoma. Slides were reviewed twice for diagnosis, with an intervening evaluation of a checklist of histologic features. Intraobserver and interobserver agreement were assessed using the kappa statistic. Intraobserver kappa values ranged from 0.67 to 0.89 (76% to 89% agreement). Interobserver kappa values by diagnostic category were: proliferative endometrium: 0.86; hyperplasia without atypia: 0.60; AH: 0.47; well-differentiated endometrioid carcinoma: 0.83; with a kappa value of 0.69 for all cases combined. Associations between the selected histologic features and the given diagnoses for each pathologist were analyzed using multiple logistic regressions to identify features that were useful for distinguishing among diagnostic categories. Histologic features determined by univariable and multivariable analyses that were found to be most associated with distinguishing diagnostic categories were: proliferative endometrium versus hyperplasia without atypia: gland crowding (univariable, multivariable), and gland branching (univariable); hyperplasia without atypia versus AH: presence of nucleoli (univariable, multivariable), nuclear enlargement (univariable), vesicular chromatin change (univariable), nuclear pleomorphism (univariable), chromatin irregularities (univariable), and loss of polarity (univariable); hyperplasia without atypia versus carcinoma: glandular confluence/complex cribriform pattern (univariable, multivariable), stromal alteration (univariable, multivariable), and necrosis (univariable). In summary, interobserver agreement was good but was lowest for AH. Only the presence of nucleoli was strongly associated with distinction of AH from hyperplasia without atypia. Individual pathologists use additional features to diagnose atypia, but these features are not consistently associated with that diagnosis. Cribriform architectural pattern and stromal alteration were associated with the distinction of well-differentiated endometrioid carcinoma from AH.

Micropapillary serous carcinoma of the ovary: an immunohistochemical and mutational analysis of p53

Micropapillary serous carcinoma (MPSC) has recently been described as a distinct ovarian neoplasm that shares histologic features with both serous borderline tumors (SBTs) and typical serous carcinomas of the ovary. To further define the relationship of MPSC to these two neoplasms, we evaluated all three tumor types for expression of the p53 protein and p53 gene mutations. The majority of MPSCs demonstrated positive, but only moderately intense, p53 immunostaining in >50% of the cells, whereas SBTs showed very weak staining in a small number of cells. In contrast, the majority of serous carcinomas displayed diffuse, very intense staining and those that did not stain completely lacked any staining for p53. This pattern of p53 immunostaining in MPSCs can be distinguished from the pattern observed in SBTs and in serous carcinomas. Both the MPSCs and the SBTs lacked p53 mutations in the cases analyzed, whereas all immunopositive serous carcinomas were found to have mutations in p53. In addition, one of the immunonegative cases of serous carcinoma had a frameshift mutation resulting in a truncated protein, providing a likely explanation for the lack of detectable p53 protein. These findings provide support for classifying MPSC as a distinct neoplasm of the ovary and suggest that increased expression of wild-type p53 may play a role in its pathogenesis.

Loss of FHIT expression in cervical carcinoma cell lines and primary tumors

Allelic deletions involving the short arm of chromosome 3 (3p13-21.1) have been observed frequently in cervical carcinomas. Recently, a candidate tumor suppressor gene, FHIT (Fragile Histidine Triad), was cloned and mapped to this chromosomal region (3p14.2). Abnormal FHIT transcripts have been identified previously in a variety of tumor cell lines and primary carcinomas, although their significance and the molecular mechanisms underlying their origin remain incompletely defined. In addition, integration of human papillomavirus DNA has been identified at a fragile site (FRA3B) within the FHIT locus in cervical cancer. These observations motivated us to evaluate FHIT mRNA and protein expression in cervical cancer cell lines, primary cervical carcinomas, and normal tissues. Transcripts of the expected size and sequence were the predominant species identified by reverse transcription (RT)-PCR in cultured keratinocytes and all normal tissues evaluated. In contrast, aberrant FHIT transcripts were readily demonstrated in 6 of 7 cervical carcinoma cell lines and 17 of 25 (68%) primary cervical carcinomas. Northern blot analyses demonstrated reduced or absent FHIT expression in the cervical carcinoma cell lines, particularly those with aberrant RT-PCR products. Immunohistochemical analysis of Fhit expression in cervical tissues revealed strong immunoreactivity in nonneoplastic squamous and glandular cervical epithelium and marked reduction or loss of Fhit protein in 25 of 33 (76%) primary cervical carcinomas. In those cervical cancer cell lines and primary tumors with exclusively aberrant or absent FHIT transcripts by RT-PCR, Fhit protein expression was always markedly reduced or absent. The frequent alterations in FHIT expression in many cervical carcinomas, but not in normal tissues, suggest that FHIT gene alterations may play an important role in cervical tumorigenesis.

Mutations in PTEN are frequent in endometrial carcinoma but rare in other common gynecological malignancies

Loss of heterozygosity of chromosome 10q has been reported in approximately 40% of endometrial carcinomas. PTEN, a candidate tumor suppressor gene located at chromosome 10q23.3, was recently identified and found to be homozygously deleted or mutated in several different types of human tumors. To determine if PTEN is a target of 10q loss of heterozygosity in carcinomas of the endometrium, we examined 32 primary endometrial carcinomas for mutations in PTEN. The tumors included the two major histopathological types of endometrial carcinoma: endometrioid (n = 26; 14 microsatellite instability (MI)-positive and 12 MI-negative) and serous (n = 6). Overall, mutations were detected in 50% of the endometrial carcinomas we analyzed. Mutations were present in 12 of 14 (86%) MI-positive and 4 of 12 (33%) MI-negative endometrioid tumors. Furthermore, mutations were found in all three histological grades of MI-positive endometrioid carcinoma. All six serous endometrial carcinomas lacked detectable mutations. To evaluate the role of PTEN in other common malignancies of the female genital tract, 12 serous ovarian carcinomas and 10 squamous cervical carcinomas were analyzed and were negative for mutations. Our results support PTEN as a tumor suppressor gene and suggest that mutations in PTEN play a significant role in the pathogenesis of the endometrioid type of endometrial carcinoma.

p53 gene mutations are common in uterine serous carcinoma and occur early in their pathogenesis

Uterine serous carcinoma (USC) is an uncommon but aggressive type of endometrial cancer associated with rapid progression of disease and a poor prognosis. Both USC and its recently described putative precursor, endometrial intraepithelial carcinoma (EIC), demonstrate strong p53 overexpression by immunohistochemistry, suggesting alteration of the p53 gene in their pathogenesis. In the present study, we evaluated 21 USCs and 9 EICs for mutations in the p53 gene using direct sequence analysis and found that 90% of USCs and 78% of EICs contain mutations. Significantly, mutations were found in 3 cases of EIC without associated invasive carcinoma and identical mutations were detected in cases with synchronous USC and EIC. Strong p53 immunoreactivity was seen in the majority of USCs and EICs and correlated with p53 gene mutation, although lack of reactivity did not always indicate the absence of a gene mutation. Loss of heterozygosity of chromosome 17p was observed in 100% of USCs and in 43% of EICs, demonstrating that loss of the wild-type p53 allele occurs early in the development of serous carcinoma. Overall, our results reveal that p53 mutations are very common in USC and EIC. The presence of p53 gene mutations in EIC further suggests that p53 alteration plays an important role early in the pathogenesis of serous carcinoma, possibly accounting for its aggressive biological behavior.

DCC genetic alterations and expression in endometrial carcinoma

DCC (Deleted in Colorectal Carcinoma) is a candidate tumor suppressor gene located on the long arm of chromosome 18. DCC was initially identified and cloned during a search for the target gene located in a region of 18q that demonstrated loss of heterozygosity (LOH) in 70 to 80% of colorectal cancers. More recently, the region of 18q harboring the DCC gene has been shown to undergo LOH in approximately 14 to 30% of endometrial carcinomas. These findings suggest that DCC may be a target of LOH in at least some endometrial carcinomas and, therefore, may have a role in the pathogenesis of this common malignancy of the female genital tract. To address this possibility, we analyzed 26 cases of endometrioid endometrial carcinoma for DCC LOH and alterations in an AT microsatellite repeat located in an intron of the DCC gene. LOH was detected in one case (4%). Allelic shifts at the DCC AT repeat were detected in five (19%) additional cases. We also evaluated DCC protein expression by immunohistochemical analysis in normal, hyperplastic, and neoplastic endometrial tissues. Three proliferative and five secretory endometria and one simple endometrial hyperplasia demonstrated staining for DCC. Four of the 26 endometrioid endometrial carcinomas for which frozen tissue was available, including at least one from each histologic grade, and a case of endometrioid carcinoma confined to the endometrium completely lacked detectable staining for DCC. Although DCC LOH was infrequent in endometrial carcinomas, alterations of the gene (LOH or AT repeat alterations) were not uncommon (23% of our cases). In addition, DCC was expressed in normal endometrial tissue, whereas expression was lost in all of the five endometrial carcinomas. The combination of the genetic alterations and loss of DCC protein expression suggests that inactivation of the DCC gene may play a role in the pathogenesis of endometrial carcinoma.

Microsatellite instability is uncommon in uterine serous carcinoma

Thirty-four uterine serous carcinomas, a type of endometrial carcinoma with aggressive behavior and a high frequency (90%) of p53 gene mutations, were analyzed for microsatellite instability (MI). Genomic DNA isolated from paired normal and tumor tissue was analyzed at eight microsatellite loci (D2S119, D2S123, D2S147, D10S197, D13S175, D18S58, D18S69, and ATn) located on four different chromosomes. All 34 tumors failed to meet the criteria for MI, defined as an alteration in the size of at least two of the microsatellite loci in tumor DNA when compared with normal DNA. Only three tumors demonstrated a shift in the size of a single microsatellite locus. Previously we reported MI in 20% of uterine endometrioid carcinomas, the most common type of endometrial carcinoma. The observed difference in the MI frequency between endometrioid and serous carcinoma is statistically significant (P = 0.003). Our data demonstrate that MI is uncommon in uterine serous carcinoma and support that different pathogenetic mechanisms are involved in the development of the two most common types of endometrial carcinoma.

Human papillomavirus E6 and E7 oncoproteins alter cell cycle progression but not radiosensitivity of carcinoma cells treated with low-dose-rate radiation

PURPOSE

Low-dose-rate radiation therapy has been widely used in the treatment of urogenital malignancies. When continuously exposed to low-dose-rate ionizing radiation, target cancer cells typically exhibit abnormalities in replicative cell-cycle progression. Cancer cells that arrest in the G2 phase of the cell cycle when irradiated may become exquisitely sensitive to killing by further low-dose-rate radiation treatment. Oncogenic human papillomaviruses (HPVs), which play a major role in the pathogenesis of uterine cervix cancers and other urogenital cancers, encode E6 and E7 transforming proteins known to abrogate a p53-dependent G1 cell-cycle checkpoint activated by conventional acute-dose radiation exposure. This study examined whether expression of HPV E6 and E7 oncoproteins by cancer cells alters the cell-cycle redistribution patterns accompanying low-dose-rate radiation treatment, and whether such alterations in cell-cycle redistribution affect cancer cell killing.

METHODS AND MATERIALS

RKO carcinoma cells, which contain wild-type P53 alleles, and RKO cell sublines genetically engineered to express HPV E6 and E7 oncoproteins, were treated with low-dose-rate (0.25-Gy/h) radiation and then assessed for p53 and p21WAF1/CIP1 polypeptide induction by immunoblot analysis, for cell-cycle redistribution by flow cytometry, and for cytotoxicity by clonogenic survival assay.

RESULTS

Low-dose-rate radiation of RKO carcinoma cells triggered p53 polypeptide elevations, p21WAF1/CIP1 induction, and arrest in the G1 and G2 phases of the cell cycle. In contrast, RKO cells expressing E6 and E7 transforming proteins from high-risk oncogenic HPVs (HPV 16) arrested in G2, but failed to arrest in G1, when treated with low-dose-rate ionizing radiation. Abrogation of the G1 cell-cycle checkpoint activated by low-dose-rate radiation exposure appeared to be a characteristic feature of transforming proteins from high-risk oncogenic HPVs: RKO cells expressing E6 from a low-risk nononcogenic HPV (HPV 11) exposed to low-dose-rate radiation arrested in both G1 and G2. Surprisingly, despite differences in cell-cycle redistribution accompanying low-dose-rate radiation treatment associated with high-risk HPV transforming protein expression, no consistent differences in clonogenic survival following low-dose-rate radiation treatment were found for RKO cell sublines expressing high-risk HPV oncoproteins and arresting only in G2 during low-dose-rate radiation exposure vs. RKO cell sublines exhibiting both G1 and G2 cell-cycle arrest when irradiated.

CONCLUSION

The results of this study demonstrate that neither HPV oncoprotein expression nor loss of the radiation-activated G1 cell-cycle checkpoint alter the sensitivity of RKO carcinoma cell lines to low-dose-rate radiation exposure in vitro. Perhaps for urogenital malignancies associated with oncogenic HPVs in vivo, HPV oncoprotein-mediated abrogation of the G1 cell-cycle checkpoint may not limit the potential efficacy of low-dose-rate radiation therapy.

Expression of HPV16 E6 or E7 increases integration of foreign DNA

In most invasive cervical carcinomas, high-risk human papillomavirus (HPV) DNA is integrated into the host genome, while in pre-invasive cervical lesions the viral genome is typically maintained exclusively as an episome. In contrast, integration of low-risk HPV DNA is rare, as is the association of low-risk HPVs with carcinomas. High-risk HPV integration is associated with a selective growth advantage of affected cells, and hence, integration is likely to be an important genetic alteration contributing to cervical tumor progression. Expression of high-risk, but not low-risk, HPV E6 or E7 proteins disrupts the p53-dependent G1 arrest that cells normally display in response to DNA damage. Absence of this cell cycle checkpoint may predispose cells containing high-risk HPVs to genetic instability and to the accumulation of the genetic alterations that appear to be required for HPV-associated cervical tumor progression. We hypothesized that integration of high-risk HPV DNA into the host cell genome may be facilitated by E6- and/or E7-mediated disruption of the normal DNA damage response pathway. To test this hypothesis, we assessed the integration frequency of a reporter plasmid (pHyGal) in RKO cells expressing individual E6 or E7 genes of either high-risk (HPV16) or low-risk (HPV6, HPV11) type viruses. Cells expressing HPV16 E6 or HPV16 E7 exhibited a significantly increased frequency of pHyGal integration in comparison to RKO control cells or cells expressing low-risk HPV E6 or E7. Thus, expression of high-risk, but not low-risk, E6 and E7 proteins increases the frequency of foreign DNA integration into the host genome. These findings suggest that at least some of the difference in oncogenic potential observed between high-risk and low-risk HPV types may be determined by the increased ability of high-risk HPVs to integrate into host DNA.

DPC4 gene in various tumor types

We recently identified a novel tumor-suppressor gene, DPC4, at chromosome 18q21.1 and found that both alleles of DPC4 were inactivated in nearly one-half of the pancreatic carcinomas. Here, we analyzed 338 tumors, originating from 12 distinct anatomic sites, for alterations in the DPC4 gene. Sixty-four specimens were selected for the presence of the allelic loss of 18q and were further analyzed for DPC4 sequence alterations. An alteration of the DPC4 gene sequence was identified in one of eight breast carcinomas and one of eight ovarian carcinomas. These results indicate that whereas DPC4 inactivation is prevalent in pancreatic carcinoma (48%), it is distinctly uncommon (< 10%) in the other tumor types examined. The tissue restriction of alterations in DPC4, as in many other tumor-suppressor genes, emphasizes the complexity of rate-limiting checkpoints in human tumorigenesis.

p53 mutations and clonality in vulvar carcinomas and squamous hyperplasias: evidence suggesting that squamous hyperplasias do not serve as direct precursors of human papillomavirus-negative vulvar carcinomas

Previous studies of vulvar carcinomas have shown two distinct subsets with respect to several clinicopathologic features. In younger women, the tumors are frequently human papillomavirus (HPV) positive, are usually of basaloid or warty histology, and are associated with vulvar intraepithelial neoplasia. In older women, the tumors are usually HPV negative, are typical keratinizing squamous carcinomas, and are associated with squamous hyperplasia--a lesion that has been purported to serve as a precursor to HPV-negative invasive carcinoma. In squamous carcinomas of the cervix, p53 inactivation (through gene mutation or interaction with the HPV E6 oncoprotein) occurs in most cases. Comparatively few studies have assessed p53 mutation and HPV status in vulvar carcinomas, and none has used molecular markers to evaluate squamous hyperplasias as direct precursors of HPV-negative invasive cancers. Of 18 invasive squamous carcinomas analyzed, seven (39%) were found to be HPV positive. Four p53 gene mutations were identified--all in HPV-negative tumors. DNA was subsequently prepared from microdissected archival tissues from all four specimens showing p53 gene mutations. DNA was separately isolated from normal squamous epithelium, invasive squamous carcinoma, and associated squamous hyperplasia. In each specimen, the p53 mutation was confirmed in the invasive tumor and absent in both normal and hyperplastic epithelium. To further investigate squamous hyperplasia as a potential precursor of HPV-negative invasive carcinoma, the authors determined the clonality of hyperplastic lesions adjacent to invasive carcinomas with p53 mutation. Clonality analyses were performed using a polymerase chain reaction (PCR)-based assay for X chromosome inactivation. Although all three informative carcinomas tested were monoclonal, corresponding normal epithelia and hyperplastic lesions were polyclonal. These findings underscore the heterogeneity of vulvar cancers with respect to loss of wild type p53 function either by interaction with the HPV E6 oncoprotein or somatic mutation of p53, and suggest that squamous hyperplasias do not serve as direct precursors of HPV-negative squamous carcinomas.