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Metastasis accounts for most cancer-associated deaths; yet, this complex process remains poorly understood, particularly the relationship between distant metastasis and primary site-derived cells. Here, we modified the classical MMTV–PyMT breast carcinoma model to trace the fate of mammary-derived carcinoma cells. We show that within the lung, when the metastatic breast carcinoma cells are conditionally depleted, transformed lung epithelial cells generate new metastases. Metastatic breast carcinoma cells transmit H19 long noncoding (lnc) RNA to lung epithelial cells through exosomes. SF3B1 bearing mutations at arginine-625 alternatively splices H19 lncRNA in lung epithelial cells, which selectively acts like a molecular sponge to sequester let-7a and induces Myc upregulation. Under the conditional elimination of primary site-derived breast carcinoma cells, lung malignant cells expressing the mutated SF3B1 splice variant dominate the newly created tumors. Our study suggests that these new carcinoma cells originating from within the colonized organ can replace the primary site-derived malignant cells whenever their expansion is abrogated using an inducible diphtheria toxin receptor in our designed system. These findings should call for a better understanding of metastatic tumors with the specific origin during cancer metastasis. [ABSTRACT FROM AUTHOR]

Four polycyclic norditerpenoids, cephalotanins A-D ( 1- 4) representing three unprecedented carbon skeletons with highly rigid ring systems, were isolated from Cephalotaxus sinensis and structurally characterized by a combination of various methods. Compounds 1 and 2 are new skeletal norditerpenoid trilactones, while 3 and 4 are two norditerpenoids featuring different new carbon skeletons. Biosynthetic pathways for 1- 4 were proposed by involving diverse and very fascinating chemical events with the coexisting cephalotane troponoids as the precursors. Compound 1 exhibited good NF- κB inhibition with an IC50 value of 4.12±0.61 μΜ. [ABSTRACT FROM AUTHOR]

Threelimonoids, trichiconin A (1) possessing a newcarbon skeleton of a rearranged A,B-ring system and trichiconins B(2) and C (3) featuring an unprecedentedA,B,D-secoskeleton, were isolated from the twigsof Trichilia connaroides. The carbon scaffold oftrichiconin A is designated as trichiconane. Their structures withabsolute stereochemistry were determined by spectroscopic data, X-raycrystallography, and CD analysis. Compounds 2and 3showed modest anti-HIV activities. [ABSTRACT FROM AUTHOR]

Two unprecedented ent -18,19-dinoricetexane diterpenoid glycosides, named abieshanesides A (1) and B (2), together with seven known compounds, have been isolated from the dead trunks and branches of Abies beshanzuensis M.H. Wu. To our knowledge, abieshanesides A and B represent the first ent -18,19-dinoricetexane diterpenoid glycosides found in natural sources. Their structures and absolute configurations were elucidated by using a combination of spectroscopic techniques and comparison of experimental and calculated electronic circular dichroism (ECD) data. The MTT experiments showed that (E)-resveratrol (7) could inhibit viability of MH7A cells with the IC 50 value of 12.5 μM. Compound 7 was able to block MH7A cell proliferation and was associated with G 0 /G 1 -phase cell cycle arrest. Flow cytometric analysis showed that the treatment by 7 significantly induced the proliferation of MH7A cells in a dose-dependent manner. [Display omitted] • Two diterpenoid glycosides and seven known compounds were isolated from Abies beshanzuensis M.H. Wu. • Abieshanesides A (1) and B (2) represent the first ent -18,19-dinoricetexane diterpenoid glycosides found in natural sources. • (E)-Resveratrol (7) could inhibit viability of MH7A cells with the IC 50 value of 12.5 μM and was able to block MH7A cell proliferation and was associated with G 0 /G 1 -phase cell cycle arrest. [ABSTRACT FROM AUTHOR]

Cytisine derivatives are a group of alkaloids containing the structural core of cytisine, which are mainly distributed in Fabaceae plants with a wide range of pharmacological activities, such as resisting inflammation, tumors, and viruses, and affecting the central nervous system. At present, a total of 193 natural cytisine and its derivatives have been reported, all of which are derived from L-lysine. In this study, natural cytisine derivatives were classified into eight types, namely cytisine type, sparteine type, albine type, angustifoline type, camoensidine type, cytisine-like type, tsukushinamine type, and lupanacosmine type. This study reviewed the research progress on the structures, plant sources, biosynthesis, and pharmacological activities of alkaloids of various types.

Purpose: To investigate the regulation of long non-coding RNA (LncRNA) RUNX1-IT1 on microrna (mir-195)/CyclinD1 (CyclinD1) in malignant pleomorphic adenoma (MPA)., Methods: The MPA tissues and para-carcinoma tissues were collected and the expression levels of LncRNA RUNX1-IT1, miR-195 and CyclinD1 mRNA were detected, the correlation and clinical pathology of MPA was analyzed and compared. MPA cell line SM-AP1 was cultured and transfected with negative control(NC) siRNA, LncRNA RUNX1-IT1siRNA, miR-NC and miR-195 inhibitor. Cell proliferation level A490 and expression levels of miR-195 and CyclinD1 were detected. LncRNA RUNX1-IT1 targeting miR-195 and miR-195 targeting CyclinD1 were analyzed by dual luciferase reporter gene assay. SPSS 21.0 software package was used for data analysis., Results: The expression level of LncRNA RUNX1-IT1 and CyclinD1 in MPA were higher than those in para tumor tissues, and the expression level of miR-195 was lower than that in para tumor tissues(P＜0.05). LncRNA RUNX1-IT1was negatively correlated with miR-195, positively correlated with CyclinD1, and miR-195 was negatively correlated with CyclinD1. The expression of LncRNA RUNX1-IT1 and CyclinD1 in MPA tissue with tumor diameter≥3 cm, recurrence and distant metastasis increased(P＜0.05), while the expression of miR-195 decreased(P＜0.05). After knockdown of LncRNA RUNX1-IT1, A490 level and CyclinD1 expression level decreased, while miR-195 expression level increased(P＜0.05). miR-195 decreased the fluorescence activity of LncRNA RUNX1-IT1 and CyclinD1 reporter genes(P＜0.05). After miR-195 was inhibited, the effect of LncRNA RUNX1-IT1 knockdown on decreasing A490 level and CyclinD1 expression level weakened(P＜0.05)., Conclusions: LncRNA RUNx1-IT1 may participate in the development of MPA by regulating the expression of miR-195/CyclinD1.

Silica gel, octadecyl-silica(ODS), Sephadex LH-20, and semi-preparative high performance liquid chromatography(HPLC) was performed to isolate nine cephalotaxine-type alkaloids from Cephalotaxus sinensis: 8-oxodeoxyharringtonine(1), 8-oxonordeoxyharringtonine(2), cephafortunine A(3), 8-oxocephalotaxine(4), deoxyharringtonine(5), acetylcephalotaxine(6), cephalotaxine(7), epicephalotaxine(8), and cephalotaxinone(9). Compounds 1 and 2 were identified for the first time and their structures were determined by high-resolution-electrospray ionization-mass spectrometry(HR-ESI-MS), nuclear magnetic resonance(NMR), and electronic circular dichroism(ECD). Compounds 1-3 and 5 significantly inhibited the transcription of nuclear factor kappa B(NF-κB), with the half-maximal inhibitory concentration(IC_(50)) of(3.91±0.70),(2.99±0.45),(7.84±0.51), and(1.46±0.17) μmol·L~(-1), respectively.

Calycanthaceae family comprises of four genera including Chimonanthus, Sinocalycanthus, Calycanthus, and Idiospermum. The plants of Calycanthaceae are popular ornamental shrubs and used as foods and medicines, which are mainly distributed in China, North America, and Australia. The plants of Calycanthaceae are rich in volatile components, alkaloids, sesquiterpenes and coumarins. Dimeric piperidinoquinoline and dimeric pyrrolidinoindoline alkaloids, dimeric and/or trimeric coumarins are characteristic compositions in these plants. In order to provide timely reference for further investigation and development of Calycanthaceae plants, we made a systemic review on chemical constituents, i.e. alkaloids, terpenoids, flavonoids, coumarins, and steroids, from Calycanthaceae plants, focusing on their chemical structures and pharmacological activities., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Fourteen new diterpenoids including clerodane (1-12), labdane (13), and norlabdane (14) types, as well as nine known analogues were isolated from the aerial parts of Croton laui. Their structures were established on the basis of spectroscopic analysis, and that of crotonolide H (11) was confirmed by single-crystal X-ray crystallography. Crotonolide A (1) exhibited moderate cytotoxicity against two tumor cell lines, HL-60 (human premyelocytic leukemia, IC50 9.42 μM) and P-388 (murine leukemia, IC50 7.45 μM), and crotonolide G (10) displayed significant antibacterial activity against a panel of Gram-positive bacteria.