Stromal invasion pattern identifies patients at lowest risk of lymph node metastasis in HPV-associated endocervical adenocarcinomas, but is irrelevant in adenocarcinomas unassociated with HPV.

OBJECTIVE: The Silva invasion pattern-based classification system stratifies endocervical adenocarcinomas (ECAs) into 3 categories corresponding to risk of metastasis and recurrence, but has only been evaluated for HPV-associated ECAs of usual type. We examined whether the Silva system is applicable to all endocervical adenocarcinomas, especially those not associated with HPV. METHODS: Complete slide sets from 341 surgical specimens of ECA were collected from 7 institutions worldwide. All specimens were associated with clinical records covering at least 5 years of follow-up. Tumors were classified as HPV-associated (HPVA) or not (NHPVA) by both morphology and detection of HPV using in situ hybridization. Recurrence and survival were analyzed by multivariate Mantel-Haenszel methods. RESULTS: Most specimens (292; 85.6%) were HPVA, while 49 (14.3%) were NHPVA. All NHPVAs were Silva pattern C, while 76.0% of HPVAs were pattern C, 14.7% pattern A, and 9.3% pattern B. Including both HPVAs and NHPVAs, lymphovascular invasion (LVI) was detected in 0% of pattern A, 18.5% of pattern B and 62.6% of pattern C cases (p < 0.001). None of the pattern A or B cases were associated with lymph node metastases (LNM), in contrast to pattern C cases (21.8%). Among patients with Silva pattern C ECA, those with HPVA tumors had a lower recurrence rate and better survival than those with NHPVA; however, when adjusted for stage at diagnosis, the difference in recurrence and mortality was small and not statistically significant. CONCLUSIONS: Application of the Silva system is only relevant in HPVA cervical adenocarcinoma.

Adjuvant chemotherapy in patients with stage I endometrioid or clear cell ovarian cancer in the platinum era: a Surveillance, Epidemiology, and End Results Cohort Study, 2000-2013.

BACKGROUND: We sought to evaluate the impact of adjuvant chemotherapy on overall survival (OS) in patients with stage I endometrioid epithelial ovarian cancer (EEOC) or ovarian clear cell cancer (OCCC) using a national database. PATIENTS AND METHODS: The Surveillance, Epidemiology, and End Results database was used to identify patients diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I EEOC or OCCC from 2000 to 2013. We sought to identify predictors of chemotherapy use and to assess the impact of chemotherapy on OS in these patients. OS was compared using the log-rank test and the Cox proportional hazards model. RESULTS: In all, 3552 patients with FIGO stage I EEOC and 1995 patients with stage I OCCC were identified. Of the 1600 patients (45%) with EEOC who underwent adjuvant chemotherapy, the 5-year OS rate was 90%, compared with 89% for those who did not undergo adjuvant chemotherapy (P = 0.807). Of the 1374 (69%) patients with OCCC who underwent adjuvant chemotherapy, the 5-year OS rate was 85%, compared with 83% (P = 0.439) for those who did not undergo adjuvant chemotherapy. Chemotherapy use was associated with younger age, higher substage, and more recent year of diagnosis for both the EEOC and OCCC groups. Only in the subgroup of patients with FIGO substage IC, grade 3 EEOC (n = 282) was chemotherapy associated with an improved 5-year OS-81% compared with 62% (P = 0.003) in untreated patients (HR: 0.583; 95% CI: 0.359-0.949; P = 0.030). In patients with OCCC, there was no significant effect of adjuvant chemotherapy on OS in any substage. CONCLUSIONS: Adjuvant chemotherapy was associated with improved OS only in patients with substage IC, grade 3 EEOC. In stage I OCCC, adjuvant chemotherapy was not associated with improved OS.

Assessment of DNA Ploidy in the ProMisE molecular subgroups of endometrial cancer.

OBJECTIVE: We sought to determine whether DNA ploidy correlates with the four molecular subgroups of endometrial carcinoma (EC) as determined using ProMisE (Proactive Molecular Risk Classifier for Endometrial Cancer). METHODS: 90 cases of EC previously characterized by clinicopathological parameters, outcomes, and ProMisE molecular subgroup (POLE EDM, MMR-D, p53 wt or p53 abn) were assessed for DNA ploidy using image cytometry. Associations of ploidy with traditional clinicopathological parameters were also tested. RESULTS: Abnormal DNA ploidy status differed amongst the ProMisE groups (p<0.001) and was found in 80.9% (17/21) of p53 abn, 37.0% (10/27) of p53 wt, 28.6% (4/14) of POLE EDM and 14.3% (4/28) of MMR-D. Abnormal DNA content was significantly associated with lower BMI (p=0.034) and grade 3 tumors (p=0.001). In the entire cohort, abnormal DNA content was significantly associated with worse progression free survival (p=0.0094) but not disease specific survival (p=0.249) or overall survival (p=0.187). When examining ploidy within each of the ProMisE groups, abnormal DNA content correlated with worse overall survival (p=0.041) and progression free survival (p=0.011) in the MMR-D group. No statistically significant relationship was seen in the remaining 3 groups. CONCLUSION: Abnormal DNA ploidy status did correlate with the molecular subgroups of EC; abnormal DNA content was seen in the large majority of p53 abn cases. Abnormal ploidy however was also seen in smaller numbers in the p53 wt, POLE EDM and MMR-D groups; therefore abnormal DNA content was not a specific marker for any one molecular group. The addition of ploidy to the ProMisE molecular categories conferred additional prognostic value within the MMR-D group, which merits further study.

The performance of BRCA1 immunohistochemistry for detecting germline, somatic, and epigenetic BRCA1 loss in high-grade serous ovarian cancer.

BACKGROUND: BRCA1 expression can be lost by a variety of mechanisms including germline or somatic mutation and promotor hypermethylation. Given the potential importance of BRCA1 loss as a predictive and prognostic biomarker in high-grade serous ovarian cancer, we sought to evaluate the utility of BRCA1 immunohistochemistry (IHC) in screening for BRCA1 loss by germline, somatic, and epigenetic mechanisms. PATIENTS AND METHODS: Patients with advanced high-grade serous ovarian cancer who had previously undergone germline BRCA1 testing were identified. Samples from each tumor were stained for BRCA1 and reviewed independently by two pathologists blinded to BRCA status. Tumors with abnormal BRCA1 IHC and wild-type germline testing underwent further evaluation for somatic BRCA1 mutations and promoter hypermethylation. McNemar's test was used to determine the association of BRCA1 IHC with germline BRCA1 mutations and BRCA1 loss through any mechanism. Kaplan-Meier methods were used to estimate overall survival (OS), and the log-rank test was used to assess differences between groups. RESULTS: Inter-rater reliability between the two pathologists on BRCA IHC interpretation was very good (kappa coefficient 0.865, P = 0.16; McNemar's test). BRCA1 IHC was abnormal in 36% (48/135) of cases. When compared with germline BRCA1 status, BRCA1 IHC had a high negative predictive value (95.4%) but a low positive predictive value (PPV, 52.1%). When accounting for promoter hypermethylation and somatic mutations as alternative methods of BRCA1 loss, the PPV rose to 87.5%. Five-year OS rate was 49.6% [95% confidence interval (CI) 26.3% to 69.3%] for patients with germline BRCA1 mutations, 50.4% (95% CI 27.5% to 69.5%) for germline wild-type BRCA1 and abnormal IHC, and 52.1% (95% CI 38.4% to 64.2%) for germline wild-type BRCA1 and normal IHC (P = 0.92). CONCLUSIONS: BRCA1 IHC interpretation was a highly reproducible and accurate modality for detecting germline, somatic, or epigenetic mechanisms of BRCA1 loss. These results support further development of BRCA1 IHC as a potential biomarker for BRCA1 loss in high-grade serous ovarian cancer.

Impact of incorporating an algorithm that utilizes sentinel lymph node mapping during minimally invasive procedures on the detection of stage IIIC endometrial cancer.

OBJECTIVE: To determine whether the frequency of cases diagnosed with stage IIIC endometrial cancer is affected by the incorporation of a modified surgical lymph node assessment. METHODS: Since 2008, we have increasingly utilized a modified nodal assessment using an algorithm that incorporates SLN mapping. For this analysis, we identified all cases of newly diagnosed endometrial cancers undergoing a minimally invasive staging procedure not requiring conversion to laparotomy from 1/1/08 to 12/31/10. Procedures were categorized as standard, modified, and hysterectomy only. Differences were based on time period: 2008 (Y1), 2009 (Y2), and 2010 (Y3). Appropriate statistical tests were used. RESULTS: We identified a total of 507 cases. The distribution of cases was 143 (Y1), 190 (Y2), and 174 (Y3). Tumor grade (P=0.05) and high-risk histologies (P=0.8) did not differ during the 3 time periods. A standard staging procedure was performed in the following cases: Y1 (93/143; 65%), Y2 (66/166; 35%), and Y3 (40/164; 23%) (P<0.001). Median operative times were as follows: Y1 (218 min), Y2 (198 min), and Y3 (176.5 min) (P<0.001). The median numbers of total lymph nodes removed among cases with at least 1 node retrieved were: Y1 (20); Y2 (10); Y3 (7) (P<0.001). Cases diagnosed as stage IIIC were as follows: Y1 (10/143; 7%), Y2 (15/166; 7.9%), and Y3 (13/164; 7.5%) (P=1.0). CONCLUSIONS: The incorporation of a modified staging approach utilizing the SLN mapping algorithm reduces the need for standard lymphadenectomy and does not appear to adversely affect the rate of stage IIIC detection.

Accuracy of frozen section diagnosis of ovarian borderline tumor.

OBJECTIVE: The objective of this study was to determine the incidence of invasive cancer in ovarian masses diagnosed as borderline tumor (BT) at the time of frozen section. METHODS: We performed a retrospective review of all patients diagnosed with ovarian BT on frozen section (FS) at our institution between 2000 and 2010. Clinical and pathologic data were extracted. Univariate and multivariate analyses were performed using standard two-sided statistical tests. RESULTS: A total of 120 patients were identified, of which 104 (86.7%) had BT on frozen section that was confirmed on final pathology. In 15 (12.5%) patients, BT was diagnosed on FS but was reclassified as invasive cancer on final pathology. One patient (0.8%) had BT on FS but benign pathology on final diagnosis. Histologies included serous in 79 (65.8%), seromucinous in 13 (10.8%), mucinous in 21 (17.5), endometrioid in 5 (4.2%), and clear cell in 2 (1.7%) patients. Reclassification of pathologic diagnosis was related to histologic subtype, but only for endometrioid and clear cell tumors (P<0.001). The rate of invasive cancer for serous micropapillary tumors on frozen section was 42.8% compared with 2.8% for serous non-micropapillary tumors (P<0.001). Tumor size >8 cm was associated with a 22.4% incidence of invasive cancer on final pathology compared to 3.2% in tumors ≤ 8 cm (P=0.004). CONCLUSION: Comprehensive surgical staging can be considered in BT >8 cm in diameter, as well as those with micropapillary serous, endometrioid, and clear cell histology diagnosed at the time of frozen section analysis.

Clinicopathologic significance of DNA mismatch repair protein defects and endometrial cancer in women 40years of age and younger.

BACKGROUND: The hereditary basis of endometrial cancer is apparent in young women with endometrial cancer. The objective of this study was to examine risk factors and outcomes in patients 40 years of age and younger with endometrial cancer. METHODS: We performed a retrospective cohort study of patients aged 40 years or less who were diagnosed with endometrial carcinoma between 1/93 and 5/08. Clinical and pathologic data were extracted from medical records. Paraffin-embedded slides from hysterectomy specimens were obtained and DNA mismatch repair (MMR) immunohistochemistry was performed. Cases were analyzed according to the presence of DNA MMR protein defects. Standard two-sided statistical tests were performed. RESULTS: Of the 56 identified patients, the median age was 36 years (range, 24-40). The majority of the endometrial carcinomas were of endometrioid histology (91%), stage I (71%), and FIGO grade 1 (59%). Abnormal DNA MMR was found in 9 cases (16%). Cases with abnormal DNA MMR had lower body mass index (BMI) (P=0.05), and had a family history suggestive of Lynch syndrome (P=0.001). Tumors were more likely to have advanced stage disease (P<0.001), be high grade (P<0.001), have deep myometrial invasion (P<0.001), and have lymphovascular invasion (P=0.002). Cases with abnormal DNA MMR had significantly worse overall survival (P=0.028) and progression-free survival (P=0.042). CONCLUSIONS: Endometrial cancer is rare in women aged 40 years or less. In this group of patients, loss of DNA MMR was associated with lower BMI, worse clinicopathologic factors, and worse outcome. These results may have implications when young women diagnosed with endometrial cancer are counseled regarding prognosis.

A nomogram for predicting overall survival of women with endometrial cancer following primary therapy: toward improving individualized cancer care.

OBJECTIVES: Traditionally we have relied mainly on final FIGO stage to estimate overall oncologic outcome in endometrial cancer patients. However, it is well known that other patient factors may play equally important roles in outcome. Our objective was to develop a clinically useful nomogram in the hope of providing a more individualized and accurate estimation of overall survival (OS) following primary therapy. METHODS: Using a prospectively maintained endometrial cancer database, 1735 patients treated between 1993 and 2008 were analyzed. Characteristics known to predict OS were collected. For each patient, points were assigned to each of these 5 variables. A total score was calculated. The association between each predictor and the outcome was assessed by multivariable modeling. The corresponding 3-year OS probabilities were then determined from the nomogram. RESULTS: The median age was 62 years (range, 25-96). Final grade included: G1 (471), G2 (622), G3 (634), and missing (8). Stage included: IA (501), IB (590), IC (141), IIA (36), IIB (75), IIIA (116), IIIB (6), IIIC (135), IVA (7), and IVB (128). Histology included: adenocarcinoma (1376), carcinosarcoma (100), clear cell (62), and serous (197). Median follow-up for survivors was 29.2 months (0-162.2 months). Concordance probability estimator for the nomogram is 0.746+/-0.011. CONCLUSION: We developed a nomogram based on 5 easily available clinical characteristics to predict OS with a high concordance probability. This nomogram incorporates other individualized patient variables beyond FIGO stage to more accurately predict outcome. This new tool may be useful to clinicians in assessing patient risk when deciding on follow-up strategies.

Lynch syndrome (hereditary non-polyposis colorectal cancer) and endometrial carcinoma.

Women with hereditary non-polyposis colorectal cancer (HNPCC)/Lynch syndrome have a high risk for endometrial cancer (EC) and frequently present with a gynaecological cancer as their first or sentinel malignancy. Identification of these patients is important given their personal and family risk for synchronous and metachronous tumours. Modalities to detect ECs for the possibility of HNPCC include microsatellite instability assay, immunohistochemistry for DNA mismatch repair proteins, MLH1 promoter hypermethylation assay and mutational analysis of DNA mismatch repair genes. The revised Bethesda guidelines provide screening criteria for HNPCC in colorectal cancers (CRCs). However, there are currently no such screening recommendations for women with endometrial carcinoma. While age and family history are useful screening criteria, their sensitivity has been shown to be low for detection of HNPCC in EC. Expansion of these criteria to include tumour morphology (presence of tumour infiltrating lymphocytes and tumour heterogeneity including dedifferentiated/undifferentiated ECs) and topography (lower uterine segment localisation) as well as presence of synchronous ovarian clear cell carcinomas may significantly enhance the detection of patients with EC at risk for HNPCC. Consideration should be given to incorporating these screening criteria into a revision of the Bethesda guidelines for detecting EC patients at highest risk for HNPCC.

A phase 2 trial of oral imatinib in patients with epithelial ovarian, fallopian tube, or peritoneal carcinoma in second or greater remission.

PURPOSE OF INVESTIGATION: To determine the effect of imatinib on progression-free survival in patients with epithelial ovarian cancer in second or greater complete clinical remission (CCR). METHODS: 35 patients were enrolled between 10/2002 and 1/2005. Eligible patients received imatinib at 400 mg daily orally. RESULTS: One patient withdrew consent, and two patients received protocol therapy in first remission and were excluded. Five patients were removed for possibly related toxicity. No associations were seen between PDGF-R staining and PFS. CONCLUSIONS: Treatment with imatinib for patients with ovarian cancer in second CCR or greater did not prolong the PFS beyond the historical estimate.

Tumor promoting properties of the ETS protein MEF in ovarian cancer.

We have previously shown that MEF (myeloid ELF1-like factor, also known as ELF4) functions as a transcriptional activator of the interleukin (IL)-8, perforin, granulocyte macrophage-colony stimulating factor (GM-CSF) and IL-3 genes in hematopoietic cells. MEF is also expressed in non-hematopoietic tissues including certain ovarian cancer cells. To define the function of MEF in these cells, we examined primary human ovarian epithelial tumors and found that MEF is expressed in a significant proportion of ovarian carcinomas, and in the CAOV3 and SKOV3 ovarian cancer cell lines, but not in normal ovarian surface epithelium. Manipulating MEF levels in these cell lines altered their behavior; reducing MEF levels, using short hairpin RNA expressing vectors, significantly inhibited the proliferation of SKOV3 and CAOV3 cells in culture, and impaired the anchorage-independent growth of CAOV3 cells. Overexpression of MEF in SKOV3 cells (via retroviral transduction) significantly increased their growth rate, enhanced colony formation in soft agar and promoted tumor formation in nude mice. The oncogenic activity of MEF was further shown by the ability of MEF to transform NIH3T3 cells, and induce their tumor formation in nude mice. MEF is an important regulator of the tumorigenic properties of ovarian cancer cells and could be used a therapeutic target in ovarian cancer.

Clinicopathologic features of early adenocarcinoma of the cervix initially managed with cervical conization.

OBJECTIVE: To evaluate the clinicopathologic features of microinvasive adenocarcinoma of the cervix in order to guide the management of patients with this disease. MATERIALS AND METHODS: A retrospective review was conducted of patients diagnosed with early invasive, 1 mm and 2 mm and 3 mm and 4 mm and

Histologic characteristics of the endometrium predicts success when utilizing autologous endometrial coculture in patients with IVF failure.

PURPOSE: To analyze the success of autologous endometrial coculture (AECC) in improving embryo quality and pregnancy outcome based on the histologic characteristic of the biopsy. METHODS: Prospective study of 86 consecutive patients undergoing IVF utilizing AECC. RESULTS: The patients were on average 37.4+/-4.0 years with a history of 2.6+/-1.8 failed previous attempts. An overall clinical pregnancy rate of 45.3% per ET was found. The embryos grown in AECC were of an improved quality in comparison to those grown in conventional media. 33.7% (29/86) of the biopsies were out of phase (>3 days). In-phase (IP) and OOP (out of phase) specimens both demonstrated an improvement in embryo quality. However, OOP endometrial biopsies that displayed significant retarded endometrial development (< cycle day 19) did not demonstrate an improvement in embryos grown on AECC as compared to IP endometrial biopsies or OOP endometrial biopsies that demonstrated at least an endometrial development of cycle day 19. CONCLUSIONS: We have demonstrated a significant improvement in embryo quality with AECC. We have also demonstrated that histologic dating of the endometrium is predictive of IVF outcome when utilizing AECC.

p53, epidermal growth factor, and platelet-derived growth factor in uterine leiomyosarcoma and leiomyomas.

Uterine leiomyosarcoma (ULMS) is an aggressive gynecological disease. Although ULMS are often found in association with benign leiomyoma (LMA), little is known regarding the relationship between these benign and malignant smooth muscle neoplasms. The objective of this study was to evaluate the expression of epidermal growth factor (EGFR), platelet-derived growth factor (PDGFR), and p53 in ULMS specimens, their prognostic relevance, and the expression of these molecular markers when compared to benign LMA specimens. Between 1991 and 2001, 25 patients were identified with high-grade primary ULMS and for whom tissue was available. Tissue microarray was created with three representative cores from each of the ULMS cases as well as from 19 patients with benign uterine leiomyomata. Immunohistochemical (IHC) staining was performed for EGFR, PDGFR, and p53. Negative and positive IHC staining was scored for each marker. Outcome analysis was performed only for ULMS. Survival was determined from the time of initial diagnosis to last follow-up. Twelve (48%) ULMS expressed p53 compared to none of the LMA (P < 0.001), and 15 (60%) ULMS cases showed PDGFR expression compared to 32% of LMA samples (P= 0.08). EGFR expression did not differ between ULMS and LMA groups. ULMS patients with p53 expression had a poorer survival compared to ULMS patients with negative expression (P= 0.07). ULMS tumor stage had the strongest association with overall survival (P= 0.05). Our study supports previous investigations indicating that p53 expression may serve as a prognostic marker for ULMS patients. The difference in PDGFR expression between ULMS and LMA demonstrated a trend toward significance. EGFR was not commonly expressed in ULMS. These uniquely expressed markers may assist in stratifying patients by survival and identify novel therapeutic markers. Clearly, further investigation is needed.

High frequency of beta-catenin mutations in borderline endometrioid tumours of the ovary.

Some low-grade endometrioid carcinomas arise from a background of endometrioid tumours of borderline malignancy. To determine the molecular mechanisms involved in the initiation of endometrioid carcinoma, the present study investigated whether the genetic alterations reported in these tumours (mutations in PTEN, KRAS, and beta-catenin genes, and microsatellite instability) are already present in endometrioid tumours of borderline malignancy. Eight endometrioid tumours of borderline malignancy were studied. By immunohistochemistry, beta-catenin was expressed in the nuclei of all tumours, suggesting the presence of stabilizing beta-catenin mutations. By mutational analysis, five different beta-catenin mutations were found in seven of eight cases (90%), affecting codons 32, 33, and 37. In contrast, only one tumour harboured a PTEN mutation, which affected codon 130. Neither KRAS mutations nor microsatellite instability was detected. A review of the literature indicated that beta-catenin mutations are characteristic of well-differentiated endometrioid carcinomas, since they were present in nearly 60% of grade I but in less of 3% of grade III tumours. In conclusion, the present study identifies beta-catenin mutation as a nearly constant molecular alteration in borderline endometrioid tumours, whereas PTEN and KRAS mutations and microsatellite instability are very infrequent. The findings in the present study, and previously reported data, strongly suggest that beta-catenin mutation is an early event in endometrioid ovarian carcinogenesis, and that it is involved in the development of low-grade endometrioid tumours.

Characterization of cyclooxygenase-2 (COX-2) during tumorigenesis in human epithelial cancers: evidence for potential clinical utility of COX-2 inhibitors in epithelial cancers.

Increased prostaglandins (PGs) are associated with many inflammatory pathophysiological conditions; and are synthesized from arachidonic acid by either of 2 enzymes, cyclooxygenase-1 (COX-1) or -2 (COX-2). Recent epidemiologic, expression, and pharmacologic studies suggest COX-2 derived metabolites also play a functional role in the maintenance of tumor viability, growth and metastasis. Archival and/or prospectively collected human tissues were prepared for immunohistochemistry, and representative cases assayed via Western blot, RT-PCR, or TAQman analysis. Consistent overexpression of COX-2 was observed in a broad range of premalignant, malignant, and metastatic human epithelial cancers. COX-2 was detected in ca. 85% of the hyperproliferating, dysplastic, and neoplastic epithelial cells, and in the existing and angiogenic vasculature within and adjacent to hyperplastic/neoplastic lesions. These data collectively imply COX-2 may play an important role during premalignant hyperproliferation, as well as the later stages of invasive carcinoma and metastasis in various human epithelial cancers.

Inducible microsomal prostaglandin E synthase is overexpressed in colorectal adenomas and cancer.

Recently, an inducible microsomal human prostaglandin E synthase (mPGES) was identified. This enzyme converts the cyclooxygenase (COX) product prostaglandin (PG) H(2) to PGE(2), an eicosanoid that has been linked to carcinogenesis. Increased amounts of PGE(2) have been observed in many tumor types including colorectal adenomas and cancers. To further elucidate the mechanism responsible for increased levels of PGE(2) in colorectal tumors, we determined the amounts of mPGES and COX-2 in 18 paired samples (tumor and adjacent normal) of colorectal cancer. With immunoblot analysis, mPGES was overexpressed in 83% of colorectal cancers. COX-2 was also commonly up-regulated in these tumors; marked differences in the extent of up-regulation of mPGES and COX-2 were observed in individual tumors. Immunohistochemistry revealed increased mPGES immunoreactivity in neoplastic cells in both colorectal adenomas and cancers compared with adjacent normal colonic epithelium. Cell culture was used to investigate the regulation of mPGES and COX-2. Chenodeoxycholate markedly induced COX-2 but not mPGES in colorectal cancer cells. Tumor necrosis factor-alpha induced both mPGES and COX-2, but the time course and magnitude of induction differed. As reported previously for COX-2, overexpressing Ras caused a several-fold increase in mPGES promoter activity. Taken together, our results suggest that overexpression of mPGES in addition to COX-2 contributes to increased amounts of PGE(2) in colorectal adenomas and cancer. The mechanisms controlling the expression of these two enzymes are not identical.

Duodenal reflux induces cyclooxygenase-2 in the esophageal mucosa of rats: evidence for involvement of bile acids.

BACKGROUND & AIMS: Reflux of duodenal contents including bile acids is believed to contribute to esophageal injury and Barrett's esophagus. Cyclooxygenase (COX)-2, an inducible form of COX, has been implicated in both inflammation and carcinogenesis. In this study, we investigated the effects of bile acids and duodenal reflux on COX-2 expression in cultured esophageal cells and tissue, respectively. METHODS: Immunoblotting and Northern blotting were used to assess the effects of bile acids on COX-2 expression in esophageal cell lines. Immunoblotting and immunohistochemistry were performed to evaluate the effects of duodenal reflux on COX-2 expression and cell proliferation in esophageal tissue. RESULTS: Unconjugated bile acids were about fivefold more potent inducers of COX-2 messenger RNA, COX-2 protein, and prostaglandin synthesis than conjugated bile acids. Acidifying the culture medium sensitized esophageal cells to bile acid-mediated induction of COX-2. The induction of COX-2 by bile acids was mediated by phosphatidylinositol-3 kinase and extracellular signal-regulated kinase 1/2 mitogen-activated protein kinases. In experimental animals, duodenoesophageal reflux led to esophagitis, marked thickening of the esophageal mucosa, and enhanced expression of COX-2. Increased immunoreactivity for Ki-67 and cyclin D1 indicated that enhanced cell proliferation contributed to mucosal thickening. CONCLUSIONS: Reflux of duodenal contents into the esophagus led to increased COX-2 expression and mucosal thickening. Bile acids are likely to contribute to these effects.

Enhanced cyclooxygenase-2 expression in sporadic and familial adenomatous polyposis of the human colon.

BACKGROUND: The cyclooxygenase (COX) enzymes exist in two related but unique isoforms (COX-1 and COX-2) and catalyze the formation of prostaglandins (PGs). COX-1 is constitutively expressed, and is responsible for the synthesis of PGs necessary for gastroprotection and normal renal function. The COX-2 isoform is important in a variety of pathophysiological conditions such as inflammation and tumorigenesis. Numerous studies report that regular use of non-steroidal anti-inflammatory drugs (NSAIDs) can decrease the incidence of some tumor types, including gastrointestinal polyposis. METHODS: In this study, we evaluated COX-1 and COX-2 expression in 30 polyps collected from 10 patients with familial adenomatous polyposis (FAP) and in 18 polyps collected from 18 patients with sporadic adenomatous polyposis (SAP) using COX-1 or COX-2 isoform-specific antibodies. All tissues were formalin-fixed and paraffin-embedded. Immunoreactivity was detected using tyramide signal amplification and evaluated utilizing an immunohistochemical scoring system. RESULTS: COX-2 was minimally detected in the distant non-neoplastic epithelium, which also served as an internal negative control. In comparison, all polyps collected from SAP or FAP patients overexpressed COX-2 in the neoplastic epithelial cells (P < or = 0.002). Additionally, pronounced COX-2 expression was observed in the stromal cells underlying and adjacent to adenomatous lesions. COX-1 immunoreactivity was weak to mild throughout each tissue evaluated and did not change in the neoplastic or stromal cells of the polyps. CONCLUSIONS: COX-2 expression is upregulated in the adenomatous epithelium of SAP and FAP, while the COX-1 isoform appears to be constitutively expressed at low levels in both neoplastic and non-neoplastic regions. The differential expression of COX-1 and COX-2 in these neoplasms suggests that COX-2 rather than COX-1 may play a role in adenoma formation and/or growth in cases of SAP and FAP in humans.

Acidic fibroblast growth factor is expressed sequentially in the progression from Barrett's esophagus to esophageal adenocarcinoma.

Acidic fibroblast growth factor 1 (FGF-1) is sequentially accumulated in Barrett's esophagus and its expression in glandular dysplasias is independent of esophageal adenocarcinoma. This suggests that FGF-1 immunohistochemistry could be used as an adjunct to the routine histopathologic diagnosis of dysplasia in Barrett's esophagus. The data also underscore the important role of fibroblast growth factors in tumorigenesis.