Expression of fibroblast activation protein-α in human deep vein thrombosis.

BACKGROUND: Fibroblast activation protein-α (FAP), a type-II transmembrane serine protease, is associated with wound healing, cancer-associated fibroblasts, and chronic fibrosing diseases. However, its expression in deep vein thrombosis (DVT) remains unclear. Therefore, this study investigated FAP expression and localization in DVT. METHODS: We performed pathological analyses of the aspirated thrombi of patients with DVT (n = 14), classifying thrombotic areas in terms of fresh, cellular lysis, and organizing reaction components. The organizing reaction included endothelialization and fibroblastic reaction. We immunohistochemically examined FAP-expressed areas and cells, and finally analyzed FAP expression in cultured dermal fibroblasts. RESULTS: All the aspirated thrombi showed a heterogeneous mixture of at least two of the three thrombotic areas. Specifically, 83 % of aspirated thrombi showed fresh and organizing reaction components. Immunohistochemical expression of FAP was restricted to the organizing area. Double immunofluorescence staining showed that FAP in the thrombi was mainly expressed in vimentin-positive or α-smooth muscle actin-positive fibroblasts. Some CD163-positive macrophages expressed FAP. FAP mRNA and protein levels were higher in fibroblasts with low-proliferative activity cultured under 0.1 % fetal bovine serum (FBS) than that under 10 % FBS. Fibroblasts cultured in 10 % FBS showed a significant decrease in FAP mRNA levels following supplementation with hemin, but not with thrombin. CONCLUSIONS: The heterogeneous composition of venous thrombi suggests a multistep thrombus formation process in human DVT. Further, fibroblasts or myofibroblasts may express FAP during the organizing process. FAP expression may be higher in fibroblasts with low proliferative activity.

An Extragastrointestinal Tumor Diagnosed as a Vaginal Mass during Pregnancy.

We report a case of an extragastrointestinal stromal tumor diagnosed as a vaginal mass during pregnancy. The mass was detected during routine examination at 24 weeks of gestation. At 26 weeks, the patient underwent transvaginal ultrasonography and magnetic resonance imaging, which revealed a blood flow-rich mass of approximately 50 × 30 mm in the rectovaginal septum. At 29 weeks of gestation, we resected the mass vaginally and the pathological diagnosis was a gastrointestinal stromal tumor. Chemotherapy was withheld until after full-term birth because the proliferation index of the tumor cells was low. The patient delivered a healthy infant. Imatinib was commenced at 1 month postpartum, with no recurrence or metastasis after 2.5 years. An extragastrointestinal stromal tumor as a vaginal mass in pregnancy has not been reported; however, our case suggests that the tumor should be considered a differential diagnosis of a vaginal mass in pregnancy.

Tissue factor expression and tumor-infiltrating T lymphocytes in ovarian carcinomas and their association with venous thromboembolism.

Ovarian cancer is a known risk factor of venous thromboembolism (VTE). Thrombogenic factor expression and lymphocytic infiltrate have been reported in endometriosis and ovarian cancers. We reviewed 30 cases of ovarian carcinomas (high grade serous carcinoma, 10; endometrioid carcinoma, 10; clear cell carcinoma (CCC), 10) and 16 endometriotic lesions. We immunohistochemically investigated the expressions of tissue factor (TF), podoplanin, P-selectin, and number of CD4 and CD8 positive lymphocytes in cancer tissue and endometriotic lesions, along with their relationship with VTE. The expression of TF was higher in CCC. The TF expression and the number of CD8 positive cells were higher in cancer tissues with VTE than in those without VTE. The podoplanin or P-selectin expression did not differ among histological types or between cases with and without VTE. Our results demonstrated a high TF expression and intraepithelial CD8 cells in CCC, which were associated with VTE. The results suggest that infiltrating lymphocytes may affect TF expression that, in turn, influences VTE.

CD39 downregulation in chronic intervillositis of unknown etiology.

Chronic intervillositis of unknown etiology (CIUE) is a rare placental lesion associated with infiltration of mononuclear inflammatory cells into the intervillous space, poor perinatal outcomes (intrauterine fetal demise or fetal growth restriction), and high rates of recurrence. CD39 is the ectonucleotidase that protects tissues from inflammatory stress and cell injury, which is localized on the surface of villi in normal placentas; however, its expression and role in CIUE are unknown. The aims of this retrospective study were to determine the expression of CD39 in CIUE and its significance in pregnancy outcomes. We compared the number of CD68- and CD3-positive cells, CD39 expression, and complement 4d (C4d) and fibrin deposition in placental tissues from patients with CIUE (n = 22) and gestational age-matched controls (n = 20), and between CIUE pregnancies with poor and good outcomes. The numbers of CD68- or CD3-positive cells were significantly higher (P < 0.0001), whereas CD39 expression on the surface of villi and endothelial cells of the stem villi was significantly lower in the CIUE group than that in controls (45% vs. 95%, P < 0.0001 and 77% vs. 96%, P < 0.001, respectively). C4d and fibrin deposition were also significantly increased in CIUE compared with those of controls. Furthermore, CD39 downregulation and the number of CD68 cells were strongly associated with poor pregnancy outcomes (P < 0.01 and P < 0.05, respectively), but other histological parameters (CD3, C4d, and fibrin) did not show this association. Our study suggests that CD39 downregulation is a useful marker of CIUE and is associated with poor pregnancy outcomes in patients with CIUE.

Expression of protease-activated receptor-2 (PAR-2) is related to advanced clinical stage and adverse prognosis in ovarian clear cell carcinoma.

Recent studies demonstrated that protease-activated receptor-2 (PAR-2) correlates with tumor progression in various tissues. On the other hand, oxidative stress arising from endometriosis has been considered a cause of carcinogenesis in ovarian clear cell carcinoma (OCCC). We previously demonstrated that oxidative stress up-regulates PAR-2 expression, and we conducted the present study to investigate the PAR-2 expression and its relation to clinicopathological factors and oxidative stress in OCCC. We performed an immunohistochemical evaluation in 95 cases of OCCC. For the evaluation of oxidative stress markers, 31 cases of ovarian endometrioid carcinoma (OEC) were also examined. No significant differences in the expression of cyclooxygenase-2 and inducible nitric oxide synthase were observed between OCCC and OEC. Sixty-two percent of the OCCC cases showed high 8-hydroxydeoxyguanosine expression, whereas all of the OEC cases showed almost negative immunoreactivities. The presence of endometriosis did not affect the expression of these oxidative stress markers or prognosis. High PAR-2 expression was observed in 20% (14/71) of the early International Federation of Gynecology and Obstetrics (FIGO) stage cases and 58% (14/24) of the advanced FIGO stage cases. High PAR-2 expression was significantly correlated with advanced FIGO stage and shorter overall survival. We found no correlations between PAR-2 expression and oxidative stress in OCCC. Our results suggest that PAR-2 plays an important role in the progression of OCCC. The expression of 8-hydroxydeoxyguanosine is a characteristic finding of OCCC, indicating that the injury of DNA by oxidative stress may be involved in the carcinogenesis of OCCC.

Endocervical Adenocarcinoma With Morphologic Features of Both Usual and Gastric Types: Clinicopathologic and Immunohistochemical Analyses and High-risk HPV Detection by In Situ Hybridization.

The fourth edition of the World Health Organization classification set up new entities of endocervical adenocarcinoma (ECA), namely the "usual type" and "gastric type." These 2 types are considered to be distinct histogenetically because of their differing immunophenotypes, human papillomavirus (HPV) status, and prognoses. Usual-type ECAs (U-ECAs) are virtually always associated with high-risk human papillomavirus (HR-HPV) infection. Gastric-type ECAs (G-ECAs) are believed not to be associated with HR-HPV infection. Morphologically, U-ECA cells are characterized by mucin-poor and eosinophilic cytoplasm, resembling endometrioid carcinoma (a pseudoendometrioid feature). G-ECA cells are characterized by abundant clear or pale, mucinous cytoplasm and distinct cell borders. However, in routine practice we noticed that some ECAs contain morphologically usual type-like components and gastric type-like components in a single tumor; we have named these "G+U" ECAs. The histogenesis of such tumors has not been investigated. We conducted the present study to clarify the clinicopathologic and immunohistochemical features and HPV status of G+U ECAs, and to determine whether G+U ECAs are genuine G-ECAs mimicking U-ECAs or genuine U-ECAs with gastric type-like morphology. We retrospectively analyzed a series of 70 consecutive cases of ECA diagnosed as mucinous ECA, endocervical type, and we reclassified them on the basis of the latest World Health Organization classification. We identified 48 (69%) pure U-ECAs, 9 pure G-ECAs, and 13 G+U ECAs. Ten of the 13 G+U ECAs (77%) showed no HR-HPV infection by in situ hybridization (HPV-unrelated G+U ECAs) and showed frequent HIK1083 expression and aberrant p53 expression in both usual type-like and gastric type-like components. The other 3 G+U ECAs showed HR-HPV infection (HPV-related G+U EACs) and frequent p16+/p53-/HIK1083- immunophenotype in both usual type-like and gastric type-like components. The U-ECAs were characterized by HR-HPV infection detected by in situ hybridization and frequent p16+/p53-/HIK1083- immunophenotype, similar to that of the HPV-related G+U ECAs. In contrast, the pure G-ECAs were characterized by the absence of HPV infection and frequent HIK1083 expression and aberrant p53 expression, similar to that of HPV-unrelated G+U ECAs. G+U ECAs thus represent a heterogenous group composed of genuine G-ECAs and genuine U-ECAs. Most of the G+U ECAs we examined were genuine HPV-unrelated G-ECAs with usual type-like components showing mucin-poor, eosinophilic cytoplasm (pseudoendometrioid morphology). A small population of G+U ECAs was genuine HPV-related U-ECAs with gastric type-like components showing mucin-rich, voluminous cytoplasm. Thus, both types of ECAs can occasionally display patterns of differentiation suggesting a component of the other type but true mixed tumors do not appear to exist. Ancillary techniques (immunohistochemical analysis of p16, p53, and HPV DNA detection assays) should be used to assure proper classification of tumors with mixed morphologic features.

Activated phosphoinositide 3-kinase δ syndrome presenting with gut-associated T-cell lymphoproliferative disease.

A 13-year-old boy was admitted to our hospital because of persistent diarrhea, abdominal pain, and bloody stools. The patient had experienced repeated hospitalizations for the treatment of respiratory infections since early childhood. Colonoscopic and pathological studies led to a diagnosis of gut-associated T-cell lymphoproliferative disease (T-cell LPD). Laboratory data showed T-lymphocytopenia (492/µl), increased serum IgG levels (1,984 mg/dl), and low serum antibody titers for specific pathogens. Combined immunodeficiency accompanied by T-LPD suggested the diagnosis of activated PI3Kδ syndrome (APDS). Genetic analyses identified a heterozygous mutation of the PIK3CD gene (c.1573 G to A p.Glu525Lys). Although prednisolone and cyclosporine therapy has controlled the T-cell LPD, this patient awaits allogeneic hematopoietic cell transplantation to achieve a complete cure of his APDS.

Is Invasive Micropapillary Serous Carcinoma a Low-grade Carcinoma?

"Invasive micropapillary serous carcinoma" has been proposed as a synonym for low-grade serous carcinoma by some expert pathologists. In contrast, Singer and colleagues reported that some serous carcinomas with conspicuous invasive micropapillary pattern (SC-IMPs) can show high-grade nuclear atypia. However, the molecular features of such tumors have not been well documented. The aim of this study was to demonstrate and emphasize the fact that high-grade serous carcinoma confirmed by immunohistochemistry and molecular analysis can show conspicuous invasive micropapillary pattern. We selected 24 "SC-IMPs" and investigated: (1) their morphologic features; (2) the immunostaining pattern of p53 protein; and (3) KRAS/BRAF/TP53 gene mutations. The 24 SC-IMPs were subdivided into low-grade and high-grade tumors based primarily on the nuclear atypia, with the mitotic rate used as a secondary feature: low grade (n=5) and high grade (n=19). Low-grade SC-IMPs were characterized by low-mitotic activity, absence of abnormal mitosis, presence of serous borderline tumor, occasional BRAF mutation, and infrequent TP53 mutation. High-grade SC-IMPs were characterized by high-mitotic activity, presence of abnormal mitosis, conventional high-grade serous carcinoma, frequent TP53 mutation, and lack of KRAS/BRAF mutation. We demonstrated that high-grade serous carcinoma confirmed by aberrant p53 immunostaining and molecular analysis can show conspicuous invasive micropapillary pattern, validating Singer and colleague's report. Serous carcinoma with conspicuous invasive micropapillary pattern should not be readily regarded as low-grade serous carcinoma. Nuclear grade is the most important diagnostic feature in the SC-IMPs.

Ovarian high-grade serous carcinoma with a noninvasive growth pattern simulating a serous borderline tumor.

Ovarian serous borderline tumors (SBTs) being a precursor of low-grade serous carcinomas are morphologically characterized by noninvasive growth and low-grade cytology. On the other hand, many pathologists regard cytologically high-grade, noninvasive (HG-noninv) ovarian serous tumors resembling SBTs in low magnification as conventional high-grade serous carcinomas (HGSCs) by personal experiences. Nonetheless, there are no established molecular characteristic of such tumors. In this study, therefore, we attempted to provide the molecular evidence. We selected 37 ovarian serous tumors that exhibited a cytologically HG-noninv growth pattern, including 36 tumors that coexisted with conventional invasive HGSC components (HG-inv) and a single tumor exclusively composed of pure HG-noninv. Histologically, all HG-noninv showed many mitotic figures, and serous tubal intraepithelial carcinomas were identified in 3 tumors with HG-noninv. Immunohistochemically, most HG-noninv showed aberrant p53 expression, frequent IMP3 positivity, p16 overexpression, a high MIB-1 labeling index, and infrequent PAX2. By molecular analysis, the pure HG-noninv and 13 HGSCs with HG-noninv showed TP53 mutations, but KRAS/BRAF mutations were not detected in any of them. In 1 tumor, we detected an identical TP53 mutation in both HG-noninv and HG-inv components by using laser capture microdissection. These immunohistochemical and molecular features of HG-noninv were similar to those of conventional invasive HGSCs but different from those of SBTs. In conclusion, our results showed that a cytologically HG-noninv growth pattern simulating an SBT is a morphological spectrum of HGSC, but not a true SBT.

Ovarian transitional cell carcinoma represents a poorly differentiated form of high-grade serous or endometrioid adenocarcinoma.

Ovarian transitional cell tumors include Brenner tumors (BTs) and transitional cell carcinoma (TCC; non-BTs) according to the most recent World Health Organization classification. However, it remains a matter of debate whether TCC represents a distinct entity or a morphologic variant of high-grade serous adenocarcinoma (HG-SC). The purpose of this study was to resolve the above question by clarifying the morphologic, immunohistochemical, and molecular features of TCC. We reviewed 488 cases of epithelial ovarian carcinomas and reclassified them on the basis of the most recent World Health Organization classification with the modifications proposed by Köbel and colleagues, and 35 cases of TCC were identified; 25 and 6 TCCs were admixed with HG-SC and endometrioid adenocarcinoma (EC), respectively, and the remaining 4 cases were pure TCC. TCC components were not observed in any clear cell carcinomas or mucinous adenocarcinomas. Only 2 cases of malignant BT were identified. In addition to TCCs, malignant BTs, and related adenocarcinomas, benign and borderline BTs were included in the following immunohistochemical and molecular analyses. Immunohistochemically, pure TCCs, TCCs admixed with HG-SC, and pure HG-SCs were characterized by frequent aberrant p53 expression (diffuse or null pattern) and WT1+/ER+/PR+/IMP2+ immunophenotype, whereas BTs, including benign, borderline, and malignant BTs, were characterized by lack of aberrant p53 expression and WT1-/ER-/PR-/IMP2- immunophenotype. In contrast to the BTs, pure ECs and TCCs admixed with EC showed an ER+/PR+ immunophenotype. Nearly all the tumors with a TP53 gene mutation by molecular analysis showed aberrant p53 staining patterns. In conclusion, TCC is not a distinct entity but a poorly differentiated form of serous or EC, as (1) most TCCs coexist with HG-SC (mostly) or EC (occasionally), and (2) the immunophenotype and molecular features are similar to those of HG-SC or EC but different from those of BTs.

"Piling up" clear cells in müllerian-type mucinous and mixed cell-type borderline tumor do not represent concomitant clear cell neoplasms.

The nature of "piling up" proliferation of clear cells in müllerian mucinous/mixed borderline tumor has not been well characterized. The purpose of this study was to clarify whether or not such clear cells represent concomitant clear cell neoplasms. First, we carefully reviewed hematoxylin and eosin slides taken from 139 ovarian tumors diagnosed as clear cell carcinoma (112 cases) and müllerian mucinous/mixed borderline tumor (27 cases) to clarify (1) the frequency of piling-up clear cells in müllerian mucinous/mixed borderline tumor and (2) the frequency of the coexistence of typical clear cell carcinoma and müllerian mucinous/mixed borderline tumor. Second, we investigated the immunohistochemical expression of estrogen receptor, hepatocyte nuclear factor-1ß, and glypican-3 in proliferating clear cells in both tumors. We identified piling-up clear cells in 56% of müllerian mucinous/mixed borderline tumors. Such clear cells lacked the severe nuclear atypia, complex branching, and dense hyalinized cores of typical clear cell carcinoma. We did not find coexistence of typical clear cell carcinoma and müllerian mucinous/mixed borderline tumor in any tumors. Piling-up clear cells and endocervical-like mucinous cells were positive for estrogen receptor but negative for hepatocyte nuclear factor-1ß and glypican-3. Most clear cell carcinomas showed a hepatocyte nuclear factor-1ß-positive/estrogen receptor-negative immunophenotype, and about half of them were glypican-3 positive. In conclusion, piling-up clear cells in müllerian mucinous/mixed borderline tumor do not represent concomitant clear cell neoplasms because clear cell carcinoma and müllerian mucinous/mixed borderline tumor hardly ever coexist and because such clear cells in both tumors are immunophenotypically distinct.

E-cadherin nuclear staining is useful for the diagnosis of ovarian adult granulosa cell tumor.

We recently have demonstrated nuclear localization of E-cadherin in ovarian adult granulosa cell tumors (Histopathology 2011;58:423). The purpose of the present study is to investigate the diagnostic utility of E-cadherin nuclear staining for the differential diagnosis between ovarian adult granulosa cell tumor and its morphological mimics. Tissue samples taken from 81 ovarian tumors and 20 extraovarian tumors were immunohistochemically stained using monoclonal anti-E-cadherin antibody recognizing cytoplasmic domain (clone 36 supplied by BD Biosciences, San Jose, CA). The ovarian tumors consisted of 30 adult granulosa cell tumors, 3 Sertoli-stromal cell tumors, 14 fibrothecomas, 5 carcinoid tumors, 1 large cell neuroendocrine carcinoma, 18 endometrioid adenocarcinomas, and 10 poorly differentiated serous adenocarcinomas. Extraovarian tumors consisted of 16 uterine endometrial stromal neoplasms and 4 pulmonary small cell carcinomas. Only tumor cells with nuclear staining were considered positive in this study. Ninety percent of adult granulosa cell tumors, 67% of Sertoli-stromal cell tumors, 64% of fibrothecomas, 75% of endometrial stromal neoplasms, 75% of small cell carcinomas, and the one large cell neuroendocrine carcinoma showed E-cadherin nuclear expression, whereas all the ovarian carcinoid tumors, endometrioid adenocarcinomas, and poorly differentiated serous adenocarcinomas were negative. E-cadherin nuclear staining is useful in distinguishing between adult granulosa cell tumors and ovarian adenocarcinomas or carcinoid tumors. However, it is of limited use for distinguishing between adult granulosa cell tumors and endometrial stromal neoplasms or small cell carcinomas. E-cadherin should be included in the immunohistochemical panel for an accurate diagnosis of ovarian adult granulosa cell tumors.

Enhancement of trypsin-induced contraction by in vivo treatment with 17beta-estradiol and progesterone in rat myometrium.

We have previously reported that the contractile response to thrombin and trypsin was enhanced in the pregnant rat myometrium. We herein determined whether or not sex hormones contribute to this enhancement and the expression of protease-activated receptors (PARs). The nonpregnant rats received daily injections of either 17beta-estradiol or progesterone, and then the contractile response of the myometrium was examined ex vivo. Treatment with either 17beta-estradiol or progesterone had almost no significant enhancing effect on the high K(+)- or oxytocin-induced contraction. On the other hand, both 17beta-estradiol and progesterone dose-dependently enhanced the contractile response to trypsin. A maximal enhancement was obtained at 25 and 40 mg kg weight(-1) day(-1) for 17beta-estradiol and progesterone, respectively. The extent of the enhancement of the trypsin-induced contraction seen in the sex hormone-treated rats in the present study was comparable to that reported in the pregnant rats. However, the contractile response to thrombin and PAR1/PAR2-AP, SFLLRNP was not enhanced either by progesterone or 17beta-estradiol. PAR2-AP and PAR4-AP failed to induce contraction under any conditions. PAR1 mRNA was scarcely detected in the control myometrium by an RT-PCR analysis, while it slightly increased only in the progesterone-treated rats. Neither PAR2 nor PAR4 mRNA was detected. We thus conclude that the responsiveness to trypsin, but not thrombin, is controlled by sex hormones. A novel type of receptor, other than PAR1, PAR2 or PAR4, is suggested to mediate the trypsin-induced contraction as in the case of the pregnant rat myometrium.