Knowledge, fatigue, and cognitive factors as predictors of lymphoedema risk-reduction behaviours in women with cancer.

OBJECTIVE: To identify social-cognitive factors predicting lymphoedema risk-reduction behaviours (hereafter, self-care) after discharge among patients in Japan with breast or gynaecological cancers, using the extended model of the theory of planned behaviour. METHODS: A cross-sectional questionnaire study was conducted in an oncology hospital. Items measured were (1) knowledge about self-care; (2) the Cancer Fatigue Scale; (3) social-cognitive factors in the theory of planned behaviour (attitudes, subjective norms, and perceived behavioural control); (4) self-care (limb hygiene, observation, articular movement, recommended risk-reduction behaviours in daily life, and diet and weight control); and (5) demographics. Of 202 respondents, 147 who had not been diagnosed with lymphoedema were eligible for statistical analysis (65.3% with gynaecological cancer, 34.7% with breast cancer). RESULTS: Structural equation modelling was used to examine a hypothesised model based on the theory of planned behaviour. The results revealed that a longer time since surgery, higher levels of fatigue, less knowledge, higher expected efficacy of self-care, and lower perceived behavioural control directly and significantly predicted less self-care behaviour. CONCLUSIONS: Besides education about self-care behaviour, levels of fatigue and perceived behavioural control should be taken into account to encourage female patients with cancer to perform self-care after discharge. Continuous psycho-educational programmes after discharge may help to facilitate self-care behaviours among long-term female cancer survivors.

Identifying selection criteria for non-radical hysterectomy in FIGO stage IB cervical cancer.

AIM: This retrospective study sought to identify the selection criteria required for a non-radical hysterectomy with minimal parametrectomy in patients with International Federation of Gynecology and Obstetrics (FIGO) stage IB invasive cervical cancer. METHODS: Overall, 461 patients with FIGO stage IB cervical cancer who underwent a radical hysterectomy were reviewed clinicopathologically according to pathological tumor size (≤2 cm, >2 - ≤4 cm, and > 4 cm). RESULTS: The pathological parametrial involvement rate in the less than equal to 2 cm group (2%) was significantly lower than in greater than 2-less than equal to 4 cm (13%) or greater than 4 cm (29%) groups (both P < 0.001). The 5-year overall survival rate was significantly higher in the less than equal to 2 cm group (97%, 95% confidence interval [CI] 94-99%) compared with greater than 2-less than equal to 4 cm (90%, 95% CI 94-86%) and greater than 4 cm (70%, 95% CI 79-60%) groups (both P < 0.001). Cox model analysis identified tumor size to be an independent prognostic factor for survival (95% CI 1.33-5.78) and recurrence (95% CI 1.31-5.66) compared to other pathological factors. However, a significant difference between the three groups was not found in rates of Grade 3 or 4 adverse events following radical hysterectomy (P = 0.19). CONCLUSIONS: Tumor size is an independent prognostic factor for survival in patients with FIGO stage IB invasive cervical cancer. This retrospective study suggests that FIGO stage IB patients with a less than equal to 2 cm tumor size are optimal candidates for non-radical hysterectomy with minimal parametrectomy, and without resulting bladder dysfunction.

Information-seeking, information sources and ongoing support needs after discharge to prevent cancer-related lymphoedema.

OBJECTIVES: To compare gynaecological and breast cancer patients in their information-seeking behaviours, usefulness of information sources and ongoing care needs after discharge to prevent the onset of lymphoedema. METHODS: We conducted a consecutive cross-sectional survey in an oncology hospital. Adult patients with stage I, II or III gynaecological or breast cancer who had undergone lymph node dissection and had not been diagnosed with lymphoedema were eligible for inclusion. The survey explored physical health status, knowledge of self-care, information-seeking behaviours, information sources and need for ongoing care from an oncology hospital and/or community health centre. RESULTS: Among 254 patients recruited, 202 responded (79.5% response rate). In total, 147 patients were eligible for statistical analysis. Irrespective of cancer type, the most commonly sought information was lymph drainage. Information on preventing weight gain was sought more often by breast cancer patients than gynaecological cancer patients. Regardless of cancer type, the most common information sources were nurses at an oncology hospital. Gynaecological cancer patients perceived nurses at the oncology hospital as useful for understanding risks, symptoms and prevention of lymphoedema. Irrespective of cancer type, ongoing need for help with lymphoedema prevention was reported both from the oncology hospital and the community centre. Limb symptoms, poor health status and poor knowledge affected the ongoing needs of gynaecological cancer patients at the oncology hospital, whereas poor health status affected ongoing needs in community health centres among both types of cancer patients. CONCLUSIONS: Both gynaecological and breast cancer patients reported ongoing care needs, but that details of information-seeking behaviours differed.

Density Gradient Centrifugation for the Isolation of Cells of Multiple Lineages.

We recently developed a simple strategy for the enrichment of mesenchymal stem cells (MSCs) with the capacity for osteoblast, chondrocyte, and adipocyte differentiation. On transplantation, the progenitor-enriched fraction can regenerate bone with multiple lineages of donor origin. Although comprising multiple precursor cell types, the population is enriched >100-fold in osteoprogenitors, hence the name "highly purified osteoprogenitors" (HipOPs). To establish a new modified method of purifying pure MSCs, it is useful to know the expression patterns of surface markers on heterogeneous MSCs and committed cells such as osteoblasts, adipocytes, and chondrocytes. However, calcium deposition by osteoblasts is a critical obstacle in visualizing the expression patterns of surface markers. We now report a new method of separating differentiated osteoblastic HipOPs (OB-HipOPs) from calcium deposits using the Percoll density gradient centrifugation technique. After centrifuge separation, calcium deposits were observed at the bottom of the centrifuge tube, and living OB-HipOPs were harvested from the 10-70% fractions. However, there were no living cells in the 70-80% fraction. We concluded that living OB-HipOPs are separated by one 10-70% Percoll gradient. Furthermore, we analyzed the expression patterns of putative MSC markers on differentiated HipOPs. FACS analysis revealed that Sca-1, CD44, CD73, CD105, and CD106 were decreased in OB-HipOPs. In adipogenic- and chondrogenic-HipOPs, Sca-1, CD73, CD105, and CD106 were decreased. This new technique is a helpful tool to identify MSC surface markers and to clarify in more detail the differentiation stages of osteoblasts.

LIF/STAT3/SOCS3 signaling pathway in murine bone marrow stromal cells suppresses osteoblast differentiation.

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine that belongs to the interleukin-6 family and is expressed by multiple tissue types. This study analyzed the effect of LIF on osteoblast differentiation using primary murine bone marrow stromal cells (BMSCs). Colony-forming unit-osteoblast formation by BMSCs was significantly suppressed by LIF treatment. To clarify the mechanism underlying the LIF suppressive effect on osteoblast differentiation, we analyzed the downstream signaling pathway of LIF. LIF/signal transducer and activator of transcription 3 (STAT3) signaling induces the expression of suppressor of cytokine signaling 3 (SOCS3). SOCS3 knockdown experiments have previously demonstrated that short-hairpin SOCS3-BMSCs reversed the LIF suppressive effect. Our results demonstrated that LIF suppresses osteoblast differentiation through the LIF/STAT3/SOCS3 signaling pathway.

Systematization of the protein sequence diversity in enzymes related to secondary metabolic pathways in plants, in the context of big data biology inspired by the KNApSAcK motorcycle database.

Biology is increasingly becoming a data-intensive science with the recent progress of the omics fields, e.g. genomics, transcriptomics, proteomics and metabolomics. The species-metabolite relationship database, KNApSAcK Core, has been widely utilized and cited in metabolomics research, and chronological analysis of that research work has helped to reveal recent trends in metabolomics research. To meet the needs of these trends, the KNApSAcK database has been extended by incorporating a secondary metabolic pathway database called Motorcycle DB. We examined the enzyme sequence diversity related to secondary metabolism by means of batch-learning self-organizing maps (BL-SOMs). Initially, we constructed a map by using a big data matrix consisting of the frequencies of all possible dipeptides in the protein sequence segments of plants and bacteria. The enzyme sequence diversity of the secondary metabolic pathways was examined by identifying clusters of segments associated with certain enzyme groups in the resulting map. The extent of diversity of 15 secondary metabolic enzyme groups is discussed. Data-intensive approaches such as BL-SOM applied to big data matrices are needed for systematizing protein sequences. Handling big data has become an inevitable part of biology.

Sequence-specific error profile of Illumina sequencers.

We identified the sequence-specific starting positions of consecutive miscalls in the mapping of reads obtained from the Illumina Genome Analyser (GA). Detailed analysis of the miscall pattern indicated that the underlying mechanism involves sequence-specific interference of the base elongation process during sequencing. The two major sequence patterns that trigger this sequence-specific error (SSE) are: (i) inverted repeats and (ii) GGC sequences. We speculate that these sequences favor dephasing by inhibiting single-base elongation, by: (i) folding single-stranded DNA and (ii) altering enzyme preference. This phenomenon is a major cause of sequence coverage variability and of the unfavorable bias observed for population-targeted methods such as RNA-seq and ChIP-seq. Moreover, SSE is a potential cause of false single-nucleotide polymorphism (SNP) calls and also significantly hinders de novo assembly. This article highlights the importance of recognizing SSE and its underlying mechanisms in the hope of enhancing the potential usefulness of the Illumina sequencers.

Establishment of a novel 70K Mac-2 binding protein antibody through screening of fucosylation-related antibodies.

Mac-2 binding protein (Mac-2bp) is a serum glycoprotein that contains seven N-glycans, and Mac-2bp serum levels are increased in patients with several types of cancer and liver disease. Mac-2bp glycosylation isomer has been applied as a clinical biomarker of several diseases, including liver fibrosis. In the present study, we identified fucosylated Mac-2bp in the conditioned medium of cancer cells resistant to anticancer therapies using glycoproteomic analyses. Fucosylation is one of the most important types of glycosylation involved in carcinogenesis and cancer stemness. To establish a next-generation glycan antibody for fucosylated Mac-2bp, we used fucosylation-deficient HEK293T cells to prepare reference Mac-2bp antigens and performed antibody screening. Unexpectedly, the 19-8H mAb obtained with our screen recognized 70K Mac-2bp, which is C-terminus-truncated product, rather than specifically recognizing fucosylated Mac-2bp. We performed immunocytochemistry using our novel 19-8H mAb, which resulted in strong cell surface staining of anticancer drug-resistant cancer cells. Therefore, our novel 19-8H mAb represents a valuable tool for cancer biology research that can help elucidate the biological function of 70K Mac-2bp.

Clinicopathological and prognostic impact of human epidermal growth factor receptor type 2 (HER2) and hormone receptor expression in uterine papillary serous carcinoma.

Uterine papillary serous carcinoma (UPSC) is a rare and aggressive variant of endometrial carcinoma. Little is known about the pathological and biological features of this tumor. Human epidermal growth factor receptor 2 (HER2) and hormone receptor (HR) expression have an important role in tumor behavior and clinical outcome, but their relevance in UPSC is not clear. In the present study, the immunohistochemical expression of HER2 and HR was assessed in 27 patients with Stage I disease, 13 with Stage II disease, 25 with Stage III disease, and 6 with Stage IV disease. Correlations between HER2 and HR expression and the clinicopathological parameters of UPSC were evaluated using Cox's univariate and multivariate analyses. For all patients, the 5-year recurrence-free survival (RFS) and overall survival (OS) rates were 51% and 66%, respectively; in patients with Stage I, II, III and IV disease, the RFS and OS were 67%/81%, 59%/77%, 43%/54% and 0%/0%, respectively. Of all 71 patients, 14% (10/71) were positive for HER2 and 52% (37/71) were positive for HR. Overexpression of HER2 was correlated with lower OS (P = 0.01), whereas HR overexpression was correlated with higher OS (P = 0.008). In multivariate models, HER2, HR, and histologic subtype were identified as independent prognostic indicators for RFS (P = 0.022, P = 0.018, and P = 0.01, respectively), but HR was the only independent factor associated with OS (P = 0.044). Thus, HER2 and HR are prognostic variables in UPSC, with HR an independent prognostic factor for OS.

KNApSAcK family databases: integrated metabolite-plant species databases for multifaceted plant research.

A database (DB) describing the relationships between species and their metabolites would be useful for metabolomics research, because it targets systematic analysis of enormous numbers of organic compounds with known or unknown structures in metabolomics. We constructed an extensive species-metabolite DB for plants, the KNApSAcK Core DB, which contains 101,500 species-metabolite relationships encompassing 20,741 species and 50,048 metabolites. We also developed a search engine within the KNApSAcK Core DB for use in metabolomics research, making it possible to search for metabolites based on an accurate mass, molecular formula, metabolite name or mass spectra in several ionization modes. We also have developed databases for retrieving metabolites related to plants used for a range of purposes. In our multifaceted plant usage DB, medicinal/edible plants are related to the geographic zones (GZs) where the plants are used, their biological activities, and formulae of Japanese and Indonesian traditional medicines (Kampo and Jamu, respectively). These data are connected to the species-metabolites relationship DB within the KNApSAcK Core DB, keyed via the species names. All databases can be accessed via the website http://kanaya.naist.jp/KNApSAcK_Family/. KNApSAcK WorldMap DB comprises 41,548 GZ-plant pair entries, including 222 GZs and 15,240 medicinal/edible plants. The KAMPO DB consists of 336 formulae encompassing 278 medicinal plants; the JAMU DB consists of 5,310 formulae encompassing 550 medicinal plants. The Biological Activity DB consists of 2,418 biological activities and 33,706 pairwise relationships between medicinal plants and their biological activities. Current statistics of the binary relationships between individual databases were characterized by the degree distribution analysis, leading to a prediction of at least 1,060,000 metabolites within all plants. In the future, the study of metabolomics will need to take this huge number of metabolites into consideration.

Prognostic impact of the history of breast cancer and of hormone therapy in uterine carcinosarcoma.

OBJECTIVE: Recent studies reveal an association between hormone therapy for breast cancer (BC), such as tamoxifen (TAM) and toremifene (TOR), and uterine carcinosarcoma (UCS). The aim of this study was to investigate the characteristics and prognosis of patients with UCS after BC and hormone therapy. METHODS: Between January 1997 and December 2007, we treated 51 patients with UCS. The medical records of these patients were reviewed, and factors that influenced their survival were retrospectively analyzed using univariate and multivariate analyses. RESULTS: Ten (19.6%) of the 51 patients had a history of BC; 6 (11.8%) had received hormone therapy with TAM or TOR. The characteristics of the patients with UCS were similar regardless of whether they had a history of BC or hormone therapy. On univariate analysis, age greater than 56 years, elevated serum lactate dehydrogenase levels, residual tumors, FIGO (International Federation of Gynecology and Obstetrics) stage higher than stage IIIa, and non-endometrioid carcinomatous components were identified as prognostic factors. On multivariate analysis, in addition to residual tumors, FIGO stage higher than stage IIIa, and non-endometrioid carcinomatous components, a history of BC (relative risk, 0.14), a history of TAM use (relative risk, 15.9), and a history of TOR use (relative risk, 16.9) were also identified as independently significant prognostic factors. CONCLUSIONS: Our data suggest that a history of BC and hormone therapy for BC is a risk factor for developing UCS without obvious impacts on the characteristics of UCS. Both of these factors had statistically significant impacts on the prognosis of patients with UCS. Further studies are necessary to clarify and validate these associations.

Serous adenocarcinoma of the uterine cervix: a clinicopathological study of 12 cases and a review of the literature.

BACKGROUND/AIMS: To determine the clinicopathological characteristics and potentially associated outcomes in patients diagnosed with serous adenocarcinoma of the uterine cervix. METHODS: The records of surgically-treated patients with pathological stage pT1b-2b serous adenocarcinoma were reviewed. RESULTS: Of 12 patients with serous adenocarcinoma who underwent radical hysterectomy, five had pT1b1N0 disease, two pT1b1N1, two pT1b2N0, and three pT2bN1. The 5-year overall survival rate for patients with or without parametrial involvement (pT2b vs. pT1b) was 0 and 89%, respectively. The 3-year recurrence-free survival rate for those with or without parametrial involvement was 33 and 89%, respectively. Four patients suffered recurrence, namely one of those who had pT1b (1/9, 11%) and 3 of those who had pT2b disease (100%). The sites of recurrence of pT2b disease were outside the pelvis in all 3 patients. Of these, 2 (67%) had peritoneal spread and 1 distant node metastasis. CONCLUSION: While patients with pathological stage pT1b disease may have a relatively favorable outcome after radical surgery, those with more advanced disease have a poor prognosis because of extra-pelvic recurrence.

Combination of squamous cell carcinoma-antigen, carcinoembryonic antigen, and carbohydrate antigen 19-9 predicts positive pelvic lymph nodes and parametrial involvement in early stage squamous cell carcinoma of the uterine cervix.

AIM: We examined the correlations between the pretreatment values of four tumor markers (squamous cell carcinoma [SCC]-antigen, carcinoembryonic antigen [CEA], carbohydrate antigen [CA]19-9, and CA125) and postsurgical high-risk factors (parametrial involvement and positive pelvic lymph nodes) in women with SCC of the uterine cervix who had International Federation of Gynecology and Obstetrics clinical stage IB and IIA disease and underwent radical hysterectomy. MATERIAL AND METHODS: In this retrospective study, we reviewed 291 patients between April 1989 and December 2008. The first 200 subjects, studied between 1989 and 2001, served as the training set, and another 91 subjects, studied between 2002 and 2008, comprised the test set. To evaluate the correlations between pretreatment tumor markers and postsurgical high-risk factors, the χ²-test and logistic regression analysis were used for univariate and multivariate analysis, respectively. RESULTS: Multivariate analysis with receiver-operator curves showed that the combination of SCC-antigen, CEA, and CA19-9 strongly predicted postsurgical high-risk factors. Analysis of the training set showed that 66.7% (95% confidence interval, 52.6-84.8%) of patients who tested positive for at least two of these three tumor markers had postsurgical high-risk factors. Similar results were obtained with the test set. CONCLUSIONS: Preoperative levels of SCC-antigen, CEA, and CA19-9 are useful for predicting the status of postsurgical high-risk factors in women with SCC of the uterine cervix who undergo radical hysterectomy.

Bone marrow-derived HipOP cell population is markedly enriched in osteoprogenitors.

We recently succeeded in purifying a novel multipotential progenitor or stem cell population from bone marrow stromal cells (BMSCs). This population exhibited a very high frequency of colony forming units-osteoblast (CFU-O; 100 times higher than in BMSCs) and high expression levels of osteoblast differentiation markers. Furthermore, large masses of mineralized tissue were observed in in vivo transplants with this new population, designated highly purified osteoprogenitors (HipOPs). We now report the detailed presence and localization of HipOPs and recipient cells in transplants, and demonstrate that there is a strong relationship between the mineralized tissue volume formed and the transplanted number of HipOPs.

Uterine Cervical Adenosarcoma Showing an Endophytic Growth Pattern.

Adenosarcomas are biphasic neoplasms that usually originate in the uterine corpus and comprise a benign epithelial component and a malignant stromal component. Uterine adenosarcomas typically present with abnormal genital bleeding, an enlarged uterus, and a tumor that protrudes into the endometrial cavity. These tumors rarely protrude through the cervical os and are often misdiagnosed as cervical polyps. We present the case of a patient with cervical adenosarcoma with characteristics different from those reported in previous cases. This tumor showed endophytic growth, which is rare in cervical adenosarcomas. No watery discharge or obvious genital bleeding was noted. Although the tumor measured 4 cm, vaginal bleeding was noted only once at 6 months before diagnosis and was in the form of faint brown discharge.

Tumor necrosis factor-alpha regulates transforming growth factor-beta-dependent epithelial-mesenchymal transition by promoting hyaluronan-CD44-moesin interaction.

Aberrant epithelial-mesenchymal transition (EMT) is involved in development of fibrotic disorders and cancer invasion. Alterations of cell-extracellular matrix interaction also contribute to those pathological conditions. However, the functional interplay between EMT and cell-extracellular matrix interactions remains poorly understood. We now show that the inflammatory mediator tumor necrosis factor-alpha (TNF-alpha) induces the formation of fibrotic foci by cultured retinal pigment epithelial cells through activation of transforming growth factor-beta (TGF-beta) signaling in a manner dependent on hyaluronan-CD44-moesin interaction. TNF-alpha promoted CD44 expression and moesin phosphorylation by protein kinase C, leading to the pericellular interaction of hyaluronan and CD44. Formation of the hyaluronan-CD44-moesin complex resulted in both cell-cell dissociation and increased cellular motility through actin remodeling. Furthermore, this complex was found to be associated with TGF-beta receptor II and clathrin at actin microdomains, leading to activation of TGF-beta signaling. We established an in vivo model of TNF-alpha-induced fibrosis in the mouse eye, and such ocular fibrosis was attenuated in CD44-null mice. The production of hyaluronan and its interaction with CD44, thus, play an essential role in TNF-alpha-induced EMT and are potential therapeutic targets in fibrotic disorders.

A rare case of recurrent ovarian cancer presenting as a round ligament metastasis.

We report a rare case of recurrent ovarian cancer presenting as a round ligament metastasis. A 44-year-old woman presented with a lower abdominal mass. Computed tomography showed a pelvic mass. Primary surgery was performed. A histopathological examination showed an ovarian serous adenocarcinoma of Stage IIIb. The patient received 6 cycles of paclitaxel and carboplatin. Almost 2 years after the initial operation, the patient noticed a left inguinal mass. Computed tomography showed a left inguinal mass, 18 mm in size. An excisional biopsy was performed and the tumor was found to originate in the left round ligament. A histopathological examination showed serous adenocarcinoma and there was no evidence of lymph node tissue. Recurrence of ovarian cancer in the round ligament is extremely rare. This unique case suggests, however, that the round ligament in rare cases may be a recurrence site for ovarian cancer, and that accurate differentiation including confirmation by diagnostic imaging and excisional biopsy, is necessary for a definitive pathological diagnosis.

Renal Subcapsular Hematoma Formation Due to Hydronephrosis Caused by Recurrent Uterine Cervical Cancer.

Most non-traumatic renal subcapsular hematomas are found in the presence of primary or metastatic renal tumors, or in the presence of vascular disease of the renal blood vessels. We managed an asymptomatic renal subcapsular hematoma that formed due to uterine cervical cancer that metastasized to the left common iliac lymph nodes. A 48-year-old woman with stage IB1 cervical cancer underwent neoadjuvant chemotherapy and concurrent chemoradiation following a radical hysterectomy. Six months after the completion of her first treatment, she developed left-sided hydronephrosis, a left subcapsular hematoma and left common iliac lymph nodes enlargement as demonstrated with contrast-enhanced computed tomography. Although a renal subcapsular hematoma is rarely a symptom of cervical cancer recurrence, it should be considered if other neoplastic or vascular diseases are ruled out.

WAPL induces cervical intraepithelial neoplasia modulated with estrogen signaling without HPV E6/E7.

Since cervical cancer still afflicts women around the world, it is necessary to understand the underlying mechanism of cervical cancer development. Infection with HPV is essential for the development of cervical intraepithelial neoplasia (CIN). In addition, estrogen receptor signaling is implicated in the development of cervical cancer. Previously, we have isolated human wings apart-like (WAPL), which is expected to cause chromosomal instability in the process of HPV-infected precancerous lesions to cervical cancer. However, the role of WAPL in the development of CIN is still unknown. In this study, in order to elucidate the role of WAPL in the early lesion, we established WAPL overexpressing mice (WAPL Tg mice) and HPV E6/E7 knock-in (KI) mice. WAPL Tg mice developed CIN lesion without HPV E6/E7. Interestingly, in WAPL Tg mice estrogen receptor 1 (ESR1) showed reduction as compared with the wild type, but cell growth factors MYC and Cyclin D1 controlled by ESR1 expressed at high levels. These results suggested that WAPL facilitates sensitivity of ESR1 mediated by some kind of molecule, and as a result, affects the expression of MYC and Cyclin D1 in cervical cancer cells. To detect such molecules, we performed microarray analysis of the uterine cervix in WAPL Tg mice, and focused MACROD1, a co-activator of ESR1. MACROD1 expression was increased in WAPL Tg mice compared with the wild type. In addition, knockdown of WAPL induced the downregulation of MACROD1, MYC, and Cyclin D1 but not ESR1 expression. Furthermore, ESR1 sensitivity assay showed lower activity in WAPL or MACROD1 downregulated cells than control cells. These data suggested that WAPL increases ESR1 sensitivity by activating MACROD1, and induces the expression of MYC and Cyclin D1. Therefore, we concluded that WAPL not only induces chromosomal instability in cervical cancer tumorigenesis, but also plays a key role in activating estrogen receptor signaling in early tumorigenesis.

Role of an ER stress response element in regulating the bidirectional promoter of the mouse CRELD2 - ALG12 gene pair.

BACKGROUND: Recently, we identified cysteine-rich with EGF-like domains 2 (CRELD2) as a novel endoplasmic reticulum (ER) stress-inducible gene and characterized its transcriptional regulation by ATF6 under ER stress conditions. Interestingly, the CRELD2 and asparagine-linked glycosylation 12 homolog (ALG12) genes are arranged as a bidirectional (head-to-head) gene pair and are separated by less than 400 bp. In this study, we characterized the transcriptional regulation of the mouse CRELD2 and ALG12 genes that is mediated by a common bidirectional promoter. RESULTS: This short intergenic region contains an ER stress response element (ERSE) sequence and is well conserved among the human, rat and mouse genomes. Microarray analysis revealed that CRELD2 and ALG12 mRNAs were induced in Neuro2a cells by treatment with thapsigargin (Tg), an ER stress inducer, in a time-dependent manner. Other ER stress inducers, tunicamycin and brefeldin A, also increased the expression of these two mRNAs in Neuro2a cells. We then tested for the possible involvement of the ERSE motif and other regulatory sites of the intergenic region in the transcriptional regulation of the mouse CRELD2 and ALG12 genes by using variants of the bidirectional reporter construct. With regards to the promoter activities of the CRELD2-ALG12 gene pair, the entire intergenic region hardly responded to Tg, whereas the CRELD2 promoter constructs of the proximal region containing the ERSE motif showed a marked responsiveness to Tg. The same ERSE motif of ALG12 gene in the opposite direction was less responsive to Tg. The direction and the distance of this motif from each transcriptional start site, however, has no impact on the responsiveness of either gene to Tg treatment. Additionally, we found three putative sequences in the intergenic region that antagonize the ERSE-mediated transcriptional activation. CONCLUSIONS: These results show that the mouse CRELD2 and ALG12 genes are arranged as a unique bidirectional gene pair and that they may be regulated by the combined interactions between ATF6 and multiple other transcriptional factors. Our studies provide new insights into the complex transcriptional regulation of bidirectional gene pairs under pathophysiological conditions.