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51.
Luteinizing hormone induces progesterone receptor gene expression in cultured porcine granulosa cells. 总被引:4,自引:0,他引:4
M Iwai K Yasuda M Fukuoka T Iwai K Takakura S Taii S Nakanishi T Mori 《Endocrinology》1991,129(3):1621-1627
We have examined the effect of LH on the regulation of the progesterone receptor (PR) in cultured porcine granulosa cells. In this study we used the RNase protection assay to evaluate the PR mRNA levels with a porcine cDNA clone isolated by the polymerase chain reaction (PCR) method. This clone was regarded as part of the porcine PR cDNA because of its 98.3% and 95.7% homology to the hormone-binding domain of human PR cDNA in amino acid and nucleotide sequences, respectively. Treatment with LH (500 ng/ml) increased porcine PR mRNA to a maximum level of 8.6 +/- 1.1-fold (mean +/- SE) after 3-h exposure. This induction was mimicked by (Bu)2cAMP as well as by FSH and hCG, and the increased PR caused by LH and (Bu)2cAMP occurred in a dose-dependent manner. Basal and LH-induced PR mRNA levels were not affected by progesterone (100 ng/ml), estrogen (100 ng/ml), and RU 486 (10 ng/ml) at 3 h. The mechanism of the increased PR mRNA levels was studied in the presence of actinomycin-D and cycloheximide. While inhibition of RNA synthesis with actinomycin-D blocked LH-induced PR mRNA expression, inhibition of protein synthesis with cycloheximide increased basal and LH-induced PR mRNA levels. These results indicate that the expression of PR mRNA is positively regulated by LH, and this induction does not require ongoing protein synthesis. There may be a cycloheximide-sensitive mechanism that modulates PR mRNA stability. From our results we suspect that progesterone modulates ovarian function through LH-induced PR in granulosa cells. 相似文献
52.
CD7+ and CD56+ Myeloid/Natural Killer Cell Precursor Acute Leukemia: A Distinct Hematolymphoid Disease Entity 总被引:11,自引:0,他引:11
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Toru Aoyama Takaki Yoshikawa Hirohito Fujikawa Tsutomu Hayashi Takashi Ogata Haruhiko Cho Takanobu Yamada Shinichi Hasegawa Kazuhito Tsuchida Norio Yukawa Takashi Oshima Yasushi Rino Munetaka Masuda 《International surgery》2014,99(6):835-841
The aim of the present study was to explore the unfavorable subset of patients with Stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0). Recurrence-free survival rates were examined in 52 patients with stage T1N2-3M0 and stage T3N0M0 gastric cancer between January 2000 and March 2010. Univariate and multivariate analyses were performed to identify risk factors using a Cox proportional hazards model. The recurrence-free survival (RFS) rates of the patients with stages T1N2, T1N3, and T3N0 cancer were 80.0, 76.4, and 100% at 5 years, respectively. The only significant prognostic factor for the survival rates of the patients with stage pT1N2-3 cancer measured by univariate and multivariate analyses was pathological tumor diameter. The 5-year RFS rates of the patients with stage pT1N2-3 cancer were 60.0%, when the tumor diameters measured <30 mm, and 88.9% when the tumor diameters measured >30 mm (P = 0.0248). These data may suggest that pathological tumor diameter is associated with poor survival in patients with small T1N2-3 tumors. Because our study was a retrospective single-center study with a small sample size, a prospective multicenter study is necessary to confirm whether small tumors are risk factor for the RFS in T1N2-3 disease.Key words: Gastric cancer, Stage II, Adjuvant chemotherapyEvery year, more than 934,000 people develop gastric cancer worldwide. After lung cancer, gastric cancer is the second most frequent cancer-related cause of death.1 Complete resection is essential to cure gastric cancer. Patients with stage II or stage III gastric cancer often develop tumor recurrence, even after complete curative resections.In 2007, the Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer (ACTS-GC) phase III trial demonstrated that S-1 is effective as adjuvant chemotherapy in Japanese patients who have undergone curative D2 gastrectomy for advanced gastric cancer.2 In general, patients eligible for ACTS-GC were those diagnosed with pathological stages II and III. However, patients classified with pathological (p) stages T1N2M0, T1N3M0, and T3N0M0—which are classified as part of stage II—were excluded from the ACTS-GC trial. Because in the prior phase III studies comparing surgery alone and adjuvant chemotherapy, patients with stages T1N+ and T2-3/N0 cancer had excellent prognoses with 5-year overall survival (OS) rates of more than 80% from surgery alone,3,4 these patients were excluded from receiving adjuvant chemotherapy. Japanese Gastric Cancer Association (JGCA) guidelines clearly state that the standard treatment for these patients is surgery alone.5Therefore, patients with stage II gastric cancer have been divided into two groups: one for whom the standard treatment is surgery alone, and the other for whom the standard treatment is surgery and adjuvant chemotherapy with S-1. Before the advent of ACTS-GC, survival rates were poorer in the latter group than in the former. However, treatment with adjuvant chemotherapy with S-1 has reversed this trend. Now, patients in the latter group receiving S-1 adjuvant chemotherapy have 5-year OS rates of 84.2%.6 Therefore, it may be old rationale that dictates that patients in the former group should be excluded from receiving adjuvant chemotherapy, because the 5-year OS rates are now more than 80% by S-1 adjuvant chemotherapy in the latter group. Five-year OS rates of 80% would not be obtained by surgery alone. Among those patients with stage II gastric cancer assigned to the surgery alone group, some may have a poor prognosis and be good candidates for adjuvant chemotherapy. The aim of the present study was to explore the unfavorable subset of patients among those with stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0). 相似文献
55.
VEGF-B selectively regenerates injured peripheral neurons and restores sensory and trophic functions
Victor H. Guaiquil Zan Pan Natalia Karagianni Shima Fukuoka Gemstonn Alegre Mark I. Rosenblatt 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(48):17272-17277
VEGF-B primarily provides neuroprotection and improves survival in CNS-derived neurons. However, its actions on the peripheral nervous system have been less characterized. We examined whether VEGF-B mediates peripheral nerve repair. We found that VEGF-B induced extensive neurite growth and branching in trigeminal ganglia neurons in a manner that required selective activation of transmembrane receptors and was distinct from VEGF-A–induced neuronal growth. VEGF-B–induced neurite elongation required PI3K and Notch signaling. In vivo, VEGF-B is required for normal nerve regeneration: mice lacking VEGF-B showed impaired nerve repair with concomitant impaired trophic function. VEGF-B treatment increased nerve regeneration, sensation recovery, and trophic functions of injured corneal peripheral nerves in VEGF-B–deficient and wild-type animals, without affecting uninjured nerves. These selective effects of VEGF-B on injured nerves and its lack of angiogenic activity makes VEGF-B a suitable therapeutic target to treat nerve injury.Nerves can be damaged either through trauma or disease. Nerves from the peripheral nervous system (PNS) have significantly greater capacity to regenerate and reinnervate their original targets after injury, compared with nerves from the CNS. The successful regeneration of PNS neurons requires a number of intrinsic and extrinsic factors, as well as a permissive microenvironment for axonal regrowth (1). Among the numerous growth factors able to induce nerve regeneration, the family of VEGFs has been implicated as a potent mediator of developmental neurogenesis and adult nerve regeneration (2–4). VEGF-A is a well-characterized and potent angiogenic factor but is also a strong inducer of nerve growth. Several studies have demonstrated that both VEGF-A and -B are expressed during peripheral nerve injury (2, 5). In the setting of injury, VEGF-B plays a role in cell survival, nerve protection, and growth (5, 6). The survival effect of VEGF-B on brain cortical neurons, retinal neurons, and motor neurons in the spinal cord is indicative of its pleiotropic role (5). VEGF-B treatment reduced stroke volume in a middle cerebral artery ligation model and increased survival of retinal ganglion cells in an optic nerve crush injury model (7), and VEGF-B knockout mice suffered severe strokes and exacerbated retinal ganglion cell death in both injury models (7–9). VEGF-B has also been used with promising results in Parkinson’s disease (10) and amyotrophic lateral sclerosis models (11).Given the ability of VEGF-B to regulate both vascular endothelial cells (angiogenesis) as well as axonal growth and survival after injury, it is unclear whether VEGF-B exerts its effects on nerve regeneration through the increase in blood supply or through direct effects on nerve tissue. Indeed, specific studies on its role on peripheral neurons independent of its vascular role are lacking. We have previously reported that VEGF-A can stimulate trigeminal neuronal cell growth and enhance cornea nerve regeneration, resulting in anatomical and functional recovery of peripheral injured nerves independently of its angiogenic effects (12). Here we studied the neuro-regenerative potential of VEGF-B in an avascular model of peripheral nerve injury in mice and the signaling elements involved in the induction of nerve growth. Our results demonstrated tha (i) peripheral nerve regeneration is impaired in mice lacking VEGF-B, (ii) VEGF-B can restore the anatomic and function innervation of target tissues by induction of nerve growth and nerve regeneration, (iii) the effects of VEGF-B are specific for injured nerves and are independent of any vascular effect, and (iv) the effects of VEGF-B on nerve regeneration are distinct from those observed for VEGF-A. 相似文献
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59.
Shinichi Hasegawa MD Takaki Yoshikawa MD PhD Yasushi Rino MD Takashi Oshima MD PhD Toru Aoyama MD Tsutomu Hayashi MD Tsutomu Sato MD Norio Yukawa MD Yoichi Kameda MD PhD Takeshi Sasaki MD PhD Hidetaka Ono MD PhD Kazuhito Tsuchida MD Haruhiko Cho MD Chikara Kunisaki MD PhD Munetaka Masuda MD PhD Akira Tsuburaya MD 《Annals of surgical oncology》2013,20(13):4252-4259
Objective
The purpose of this study was to clarify the priority of nodal dissection in Siewert types II and III adenocarcinoma of the esophagogastric junction (AEG).Methods
The priority of nodal dissection was evaluated based on the therapeutic value index calculated by multiplying of the frequency of metastasis to each station and the 5-year survival rate of patients with metastasis to that station.Results
A total of 176 patients (95 type II and 81 type III) were examined. Among the lymph nodes that had a metastatic incidence exceeding 10 %, the stations showing the first to fourth highest index were the paracardial and lesser curvature nodes (Nos. 1, 2, and 3) and the node at the root of the left gastric artery (No. 7) in the total cohort, as well as in each type. The next station was the lower thoracic paraesophageal lymph node (No. 110), followed by the nodes along the proximal splenic artery (No. 11p) in type II, whereas it was the nodes along the proximal splenic artery (No. 11p) followed by the para-aortic nodes (No. 16a2), the nodes at the celiac artery (No. 9), and the nodes around the splenic hilum (No. 10) in type III.Conclusions
These results suggest that the highest priority nodal stations to be dissected were the paracardial and lesser curvature nodes (Nos. 1, 2, and 3) and the nodes at the root of the left gastric artery (No. 7), regardless of the Siewert subtype, but the subsequent priority was different depending on the subtype. 相似文献60.
Shigeoka Y Igishi T Matsumoto S Nakanishi H Kodani M Yasuda K Hitsuda Y Shimizu E 《Journal of cancer research and clinical oncology》2004,130(3):146-152
Cell migration is essential for invasive and metastatic phenotypes of cancer cells. Potential chemopreventive agents of cancer—sulindac sulfide, caffeic acid phenethyl ester (CAPE), curcumin, and (+)-catechin—have been reported to interfere with several types of intracellular signaling. In this study, we examined the effects of these agents on transforming growth factor-(TGF-)-induced motility and Akt phosphorylation in A549 cells. Judged by gold particle phagokinesis assay, sulindac sulfide, CAPE, and curcumin suppressed the motility of A549 cells promoted by TGF-. LY294002, a specific inhibitor of phosphatidylinositol 3-kinase(PI3K)/Akt signaling, also suppressed TGF--induced motility and Akt phosphorylation. Sulindac sulfide and CAPE, but not curcumin, suppressed TGF--induced Akt phosphorylation. We conclude that sulindac sulfide and CAPE suppress the motility promoted by TGF- in lung adenocarcinoma cells through the suppression of Akt. Our observations raise the possibility that these agents, except for (+)-catechin, can be applied not only as chemopreventive agents but also as anti-metastatic therapy.Abbreviations CAPE
Caffeic acid phenethyl ester
- TGF-
Transforming growth factor-
- FAK
Focal adhesion kinase
- MMP-2
Matrix metalloproteinase-2 相似文献