Organopalladium catalyst on S-terminated GaAs(001)-(2×6) surface

Organopalladium molecules, such as Pd(CH3COO)2 ({Pd}), immobilized on the S-terminated GaAs(001), termed GaAs–S–{Pd} have high catalytic activity and cycle durability in the Mizoroki–Heck reaction. It is thought that the presence of Ga–S bonds in the single atomic layer S-termination is essential for these catalytic properties despite the much higher thickness (~100 nm) of the {Pd} films. In this study, the authors demonstrate the retention of Ga–S bonds in ultrathin GaAs–S–{Pd} by using reflection high-energy electron diffraction and scanning tunneling microscopy (STM). The ultrathin GaAs–S–{Pd} was prepared by using a vapor-deposition technique. Deposited {Pd} was observed as ~1 nm dotlike structures with STM. The adsorption rate of {Pd} was also investigated

A potential diagnostic biomarker: Proteasome LMP2/b1i-differential expression in human uterus neoplasm

Uterine leiomyosarcoma (ULMS) develops more often in the muscle tissue layer of the uterine body than in the uterine cervix. The development of gynecologic tumors is often correlated with female hormone secretion; however, the development of uterine ULMS is not substantially correlated with hormonal conditions, and the risk factors are not yet known. Importantly, a diagnostic-biomarker which distinguishes malignant ULMS from benign tumor leiomyoma (LMA) is yet to be established. Accordingly, it is necessary to analyze risk factors associated with uterine ULMS, to establish a treatment method. Proteasome low-molecular mass polypeptide 2(LMP2)/b1i-deficient mice spontaneously develop uterine LMS, with a disease prevalence of ~40% by 14 months of age. We found LMP2/b1i expression to be absent in human LMS, but present in human LMA. Therefore, defective-LMP2/b1i expression may be one of the risk factors for ULMS. LMP2/b1i is a potential diagnostic-biomarker for uterine ULMS, and may be a targeted-molecule for a new therapeutic approach

Versatile and Enantioselective Preparation of Planar-Chiral Metallocene-Fused 4-Dialkylaminopyridines and Their Application in Asymmetric Organocatalysis

A series of ferrocene-fused planar-chiral N-tosyl-4-pyridones (S)-2b-d were prepared in enantiomerically pure forms. Starting with the chiral ferrocenyl acetals, 1-[(2S,4S)-4-methoxymethyl-1,3-dioxan-2-yl]-1',2',3',4',5'-R5-ferrocenes ((–)-3b, R = Me; (–)-3c, R = Ph; (–)-3d, R = Bn), N-tosylamino and formyl groups were introduced at the 1- and 2-positions of the ferrocene cores in (S)-11b-d with control of the planar chirality. After the reaction with ethynylmagnesium bromide, generated propargyl alcohol derivatives (S)-17 were treated with MnO2 and catalytic TBAI to give the planar-chiral pyridones by the iodide-catalyzed cyclization. This method is highly practical with a shorter and higher-yield sequence without using noble metal catalysts. Planar-chiral ferroco-pyridones (S)-2b-d were reacted with various Me3Si-NR'2 to give a library of ferrocene-fused 4-dialkylaminopyridines ((S)-1, DAAPs) in high yields as single-enantiomers by the detosylative amination. The cymantrene-fused DAAPs were also prepared in the same way. The library of the chiral DAAPs were examined in the two asymmetric reactions as organocatalysts, and some newly prepared Fc-DAAPs showed better enantioselectivity than the known species

Molecular Approach to Uterine Leiomyosarcoma: LMP2-Deficient Mice as an Animal Model of Spontaneous Uterine Leiomyosarcoma

Uterine leiomyosarcoma (LMS) develops more often in the muscle tissue layer of the uterine body than in the uterine cervix. The development of gynecologic tumors is often correlated with female hormone secretion; however, the development of uterine LMS is not substantially correlated with hormonal conditions, and the risk factors are not yet known. Importantly, a diagnostic-biomarker which distinguishes malignant LMS from benign tumor leiomyoma (LMA) is yet to be established. Accordingly, it is necessary to analyze risk factors associated with uterine LMS, in order to establish a treatment method. LMP2-deficient mice spontaneously develop uterine LMS, with a disease prevalence of ~40% by 14 months of age. We found LMP2 expression to be absent in human LMS, but present in human LMA. Therefore, defective LMP2 expression may be one of the risk factors for LMS. LMP2 is a potential diagnostic-biomarker for uterine LMS, and may be targeted-molecule for a new therapeutic approach

Identification Of Novel Biomarker For Human Uterine Leiomyosarcoma

Sarcomas are neoplastic malignancies that typically arise in tissues of mesenchymal origin. The identification of novel molecular mechanisms leading to sarcoma formation and the establishment of new therapies has been hampered by several critical factors. Human uterine leiomyosarcoma (Ut-LMS) develops more frequently in the muscle tissue layer of the uterine body than in the uterine cervix. Although the development of gynecologic tumors is often correlated with the secretion of female hormones; that of human Ut-LMS does not and its risk factors remain unknown. Importantly, a diagnostic biomarker that can distinguish malignant Ut-LMS from benign tumor uterine leiomyoma (LMA) has yet to be established. Therefore the risk factor(s) associated with human Ut-LMS to establish a diagnosis and novel therapeutic method. Proteasome b-ring subunit LMP2/b1i-deficient mice spontaneously develop Ut-LMS, with a disease prevalence of ~40% by 14 months of age. We shown that LMP2/b1i expression was absent in human Ut-LMS, but present in other human uterine mesenchymal tumors including uterine LMA. Therefore, defective-LMP2/b1i expression may be one of the risk factors for human Ut-LMS. LMP2/b1i is a potential diagnostic biomarker for human Ut-LMS, and may be a targeted-molecule for a new therapeutic approach

Pathobiology of Human Uterine Leiomyosarcoma for Development of Novel Diagnosis and Clinical Therapy

Uterine sarcomas comprise a group of rare tumours with differing tumour pathobiology, natural history and response to clinical treatment. Diagnosis is often made following surgical treatment for presumed malignant mesenchymal tumours and benign tumours. Currently pre-operative diagnosis does not reliably distinguish between malignant mesenchymal tumours, Uterine Leiomyosarcoma (U-LMS) and benign tumours including Leiomyomas (LMA). U-LMS is the most common sarcoma but other subtypes include endometrial stromal sarcoma (low grade and high grade), undifferentiated uterine sarcoma and adeno sarcoma. Clinical trials have shown no definite survival benefit for adjuvant radiotherapy or chemotherapy, and have been hampered by the rarity and heterogeneity of these tumour types. There is a role of adjuvant treatment in carefully selected cases following multidisciplinary discussion at U-LMS reference centres. In patients with metastatic LMS then systemic chemotherapy can be considered. Accordingly, it is necessary to analyse risk factors associated with human U-LMS, in order to establish a treatment method. Proteasome β-subunit 9 (PSMB9)/β1i-deficient mice spontaneously develop U-LMS, with a disease prevalence of ~37% by 12 months of age. We found PSMB9/β1i expression to be absent in human U-LMS, but present in human LMA. Therefore, defective PSMB9/β1i expression may be one of the risk factors for human U-LMS. PSMB9/β1i is a potential diagnostic-biomarker for human U-LMS, and may be targeted-molecule for a new therapeutic approach. Keywords: PSMB9/β1i; Diagnosis; Mesenchymal tumour; Leiomyosarcoma; Leiomyom

Peritoneal dissemination of high-grade serous ovarian cancer: pivotal roles of chromosomal instability and epigenetic dynamics

Epithelial ovarian cancer remains the lethal gynecological malignancy in women. The representative histotype is high-grade serous carcinoma (HGSC), and most patients with HGSC present at advanced stages with peritoneal dissemination. Since the peritoneal dissemination is the most important factor for poor prognosis of the patients, complete exploration for its molecular mechanisms is mandatory. In this narrative review, being based on the clinical, pathologic, and genomic findings of HGSC, chromosomal instability and epigenetic dynamics have been discussed as the potential drivers for cancer development in the fallopian tube, acquisition of cancer stem cell (CSC)-like properties, and peritoneal metastasis of HGSC. The natural history of carcinogenesis with clonal evolution, and adaptation to microenvironment of peritoneal dissemination of HGSC should be targeted in the novel development of strategies for prevention, early detection, and precision treatment for patients with HGSC

Tumor Immunoediting, from T Cell-Mediated Immune Surveillance to Tumor-Escape of Uterine Leiomyosarcoma

The majority of smooth muscle tumors found in the uterus are benign, but uterine leiomyosarcomas (LMSs) are extremely malignant, with high rates of recurrence and metastasis. The development of gynecologic tumors is often correlated with female hormone secretion; however, the development of uterine LMS is not substantially correlated with hormonal conditions, and the risk factors are not clearly understood. The presentation of antigenic peptides by major histocompatibility complex (MHC) class I molecules is important for tumor rejection by cytotoxic T-lymphocytes (CTLs). Such antigenic peptides are generated as a result of the degradation of intracellular proteins by the proteasome pathway, a process that is influenced by the interferon (IFN)-γ-inducible low molecular mass polypeptide-2 (LMP2) subunit of the 20S proteasome. Homozygous deficient mice for LMP2 are now known to spontaneously develop uterine LMS. LMP2 expression is reportedly absent in human uterine LMS, but present in human myometrium. Further studies revealed a few infiltrating CD56+ NK cells in human uterine LMS tissues. This review aims at summarizing recent insights into the regulation of NK cell function and the T cell-mediated immune system as tumor immune surveillance, first attempts to exploit NK cell activation to improve immunity to tumors

The somatic mutations in Interferon-γ signal molecules in human uterine leiomyosarcoma

Human uterine leiomyosarcoma (U-LMS) is neoplastic malignancy that typically arises in tissues of mesenchymal origin. The identification of novel molecular mechanism leading to human U-LMS formation and the establishment of new therapies has been hampered by several critical points. We earlier reported that mice with a homozygous deficiency for proteasome beta subunit 9 (Psmb9)/β1i, an interferon (IFN)-γ inducible factor, spontaneously develop U-LMS. The use of research findings of the experiment with mouse model has been successful in increasing our knowledge and understanding of how alterations, in relevant oncogenic, tumour suppressive, and signaling pathways directly impact sarcomagenesis. The IFN-γ pathway is important for control of tumour growth and invasion and has been implicated in several malignant tumours. In this study, experiments with human tissues revealed a defective expression of PSMB9/β1i in human U-LMS that was traced to the IFN-γ pathway and the specific effect of somatic mutations of JANUS KINASE (JAK) 1 molecule or promoter region on the locus cording PSMB9/β1i gene. Understanding the molecular mechanisms of human U-LMS may lead to identification of new diagnostic candidates or therapeutic targets against human U-LMS