LINC00174 triggers the malignant development of breast cancer by negatively regulating miR-1827 level.

OBJECTIVE: Long non-coding RNAs (lncRNAs) are extensively involved in tumor development. In-depth researches on cancer-associated lncRNAs provide a theoretical basis for developing prognostic hallmarks and individualized therapeutic targets in breast cancer (BCa). This study aims to detect expression characteristics of LINC00174 in BCa and its biological role in regulating BCa cell phenotypes. PATIENTS AND METHODS: LINC00174 levels in BCa and adjacent normal tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The influence of LINC00174 on pathological indicators of BCa was analyzed. In MCF-7 and MDA-MB-231 cells with LINC00174 knockdown, proliferative and migratory abilities were examined by cell counting kit-8 (CCK-8), colony formation and transwell assay, respectively. At last, molecular mechanisms of LINC00174 and its downstream gene miR-1827 in regulating BCa development were explored by Luciferase assay and rescue experiments. RESULTS: LINC00174 was upregulated in BCa tissues than adjacent normal ones. High level of LINC00174 predicted advanced tumor staging, high metastasis rate and poor prognosis in BCa. Knockdown of LINC00174 attenuated proliferative and migratory abilities in BCa cells. MiR-1827 was the target gene binding LINC00174, showing a negative correlation between each other. Silence of miR-1827 abolished the regulatory effects of LINC00174 on proliferative and migratory abilities in BCa cells. CONCLUSIONS: LINC00174 is upregulated in BCa samples. It is closely linked to tumor staging, metastasis and prognosis in BCa. By negatively regulating miR-1827 level, LINC00174 aggravates the malignant development of BCa.

Natural killer cell-derived exosome-entrapped paclitaxel can enhance its anti-tumor effect.

OBJECTIVE: To study the effectiveness of natural killer cell-derived exosome (NK-Exos)-entrapped paclitaxel (PTX-NK-Exos) in enhancing its anti-tumor effect. MATERIALS AND METHODS: The NK-Exos were isolated through ultra-high-speed centrifugation, and the PTX-NK-Exos system was constructed via electroporation. The morphology, particle size, Zeta potential and entrapment rate of PTX-NK-Exos were evaluated using transmission electron microscope (TEM), dynamic light scattering (DLS), Western blotting and high-performance liquid chromatography (HPLC), respectively. The uptake of Exos in human breast cancer MCF-7 cells was observed under a laser confocal microscope. Moreover, the effect of PTX-NK-Exos on MCF-7 cell viability was determined through methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and 4',6-diamidino-2-phenylindole (DAPI) staining. The effects of PTX-NK-Exos on messenger ribonucleic acid (mRNA) and protein expressions of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax) and Caspase-3 in MCF-7 cells were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting, respectively. RESULTS: The NK-Exos were successfully isolated via ultra-high-speed centrifugation, and they had uniform particle size and high expression of markers for Exos. MCF-7 cells could take up Exos. The PTX-NK-Exos drug delivery system was successfully prepared using electroporation. In PTX group and NK-Exos group, the proliferation of MCF-7 cells declined, the nuclear apoptosis was evident and the apoptosis rate of MCF-7 cells rose compared with those in Control group. In PTX group and PTX-NK-Exos group, the migration of MCF-7 cells declined compared with that in Control group. According to the results of qRT-PCR and Western blotting, PTX-NK-Exos exerted an anti-tumor effect through inducing the up-regulation of Bax and Caspase-3 in the apoptotic signaling pathway in tumor cells. CONCLUSIONS: Exos isolated through ultra-high-speed centrifugation can be used to prepare the PTX-NK-Exos drug delivery system through electroporation. Drug-loaded Exos can effectively inhibit proliferation and induce apoptosis of tumor cells, thereby exerting an anti-tumor effect.

LncRNA TERC alleviates the progression of osteoporosis by absorbing miRNA-217 to upregulate RUNX2.

OBJECTIVE: To elucidate the role of telomerase RNA elements (TERC) in alleviating osteoporosis (OP) by absorbing microRNA-217 (miRNAs-217) to regulate runt-related transcription factor 2 (RUNX2) level. MATERIALS AND METHODS: The serum levels of TERC and miRNA-217 in OP patients and healthy controls were determined. During the osteogenic process, the relative levels of alkaline phosphatase (ALP), RUNX2, and Osterix were determined in hMSCs. The regulatory effects of TERC, miRNA-217, and RUNX2 on ALP and RUNX2 levels in hMSCs were examined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot. In addition, the changes in ALP activity and calcification ability in hMSCs influenced by them were assessed through ALP activity determination and alizarin red staining, respectively. The interaction of TERC/miRNA-217/RUNX2 regulatory loop and its role in influencing hMSCs osteogenesis were assessed by Dual-Luciferase Reporter Gene Assay and a series of rescue experiments, respectively. RESULTS: The downregulated TERC and upregulated miRNA-217 were identified in the serum of the OP patients. Consistently, the downregulated TERC and upregulated miRNA-217 were discovered in in vitro osteogenic process of hMSCs. The silence of TERC, or RUNX2 downregulated ALP and RUNX2 levels, decreased ALP activity and attenuated the calcification ability in hMSCs. The overexpression of miRNA-217 gave similar results. The binding relationship in TERC/miRNA-217/RUNX2 regulatory loop was verified. At last, rescue experiments suggested that TERC accelerated hMSCs osteogenesis by absorbing miRNA-217 to upregulate RUNX2. CONCLUSIONS: The serum level of TERC is lowly expressed in OP patients. TERC influences hMSCs osteogenesis by absorbing miRNA-217 to upregulate RUNX2, thus alleviating the progression of OP.

Effects of alendronate on osteoporosis treatment and levels of related cytokines.

Alendronate regulates the activity of osteoclasts and healing of osteoporosis. This study investigated the effect of alendronate on bone healing and changes in the levels of cytokines. Bilateral ovaries of 10 adult female rabbits were removed surgically in aseptic condition to establish the animal model of osteoporosis. Five rabbits in group A were treated with alendronate (1.15 mg·kg-1·week-1) once a week by a stomach tube, whereas the remaining 5 in group B were treated with physiological saline. The success of the animal model establishment and the efficacy of alendronate treatment were evaluated by the sports ability score and the Basso, Beattie, and Bresnahan (BBB) score; the healing degree of osteoporosis was determined by X-ray analysis and measurement of biomechanical properties; the changes in the levels of related cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining. Treatment improved dyskinesia of the animals in group A than that in group B, with significant improvement occurring in the 4th week of treatment. The BBB score of the group A animals revealed movements similar to normal, but that of the group B animals exhibited significant motor disturbance (P < 0.01). X-ray examination showed that with time, the X-ray ratings increased. Measurement of the biomechanical properties further showed that alendronate had a positive effect on osteoporosis healing. The results of ELISA and immunohistochemistry showed that the levels of ALP, BMP-2, bFGF, and IGF-1 were upregulated in group A. In conclusion, alendronate accelerated osteoporosis healing probably via certain cytokine-related mechanism.

Lifestyle, environmental pollution and lung cancer in cities of Liaoning in northeastern China.

Several studies were conducted in cities of Liaoning Province, one of the areas of China with heavy concentrations of industry, to investigate the effects of life-style factors and environmental pollutants on lung cancer causation. A case-control study involving 1249 lung cancer patients and 1345 population-based controls was conducted in 1985-1988 in Shenyang, the capital of Liaoning. Cigarette smoking was found to be the principal cause of lung cancer in this population, accounting for 55% of the disease in males and 37% in females. There was also a significant increase in lung cancer risk associated with an overall index of indoor air pollution due to coal-burning emission. The population attributable risk (PAR) for indoor air pollution was 13% for males and 17% for females. Risks were significantly increased for workers in the non-ferrous smelter (odds ratio (OR) = 2.6, 95% CI, 1.3-5.1), chemical and drug manufacturing (OR = 3.0, 95% CI, 1.0-8.0), and the glass and pottery industry (OR = 1.6, 95% CI, 1.0-2.5). Studies in the Anshan Iron-Steel Complex showed a significant excess of lung cancer for workers exposed to a variety of dusts. A standardized proportional mortality ratio (SPMR) study of 8887 deaths during 1980-1989 among male workers of the complex indicated a 37% excess risk of lung cancer compared to residents of the city. A nested case-control study was then conducted in that complex. A total of 610 cases of lung cancer diagnosed during 1987-1993 and 959 randomly selected controls from 196 993 active and retired employees of the complex were interviewed. Historical monitoring records for dust and benzo(a)pyrene (B(a)P) were collected from 1956-1992 to calculate cumulative exposure for each person. Results suggested that risks were increased for all occupations in which there was exposure to dusts, with the highest risks seen among coke oven workers (OR = 3.5, 95% CI, 2.0-6.4) and fire-resistant brick makers (OR = 2.9, 95% CI, 1.9-4.4). Significant dose-response patterns between cumulative total dust, cumulative total B(a)P and lung cancer risk were observed. The findings suggest that smoking and environmental pollution combine to account for elevated rates of lung cancer in cities of northeastern China.

Inhibition of substance P-induced vascular leakage in rat by N-acetyl-neurotensin-(8-13).

Substance P (SP) administered 40 micrograms/kg s.c. to pentobarbital-anesthetized rats induced salivation and leakage of plasma constituents into the skin, muscle, trachea, esophagus and bladder, as measured by Monastral blue B labeling of small blood vessels or by extravasation of Evans blue dye into tissues. These SP effects were inhibited by N-acetyl-neurotensin-(8-13) (Ac-NT-(8-13)) and by CP-96,345, a nonpeptide SP receptor antagonist. Intralumenal injection of Ac-NT-(8-13) or CP-96,345 into the bladder reduced SP-induced leakage of Evans blue dye but not dye leakage into the pawskin, indicating a localised drug action. Ac-NT-(8-13) appears to act directly on discrete sites in skin and in mucous membranes to functionally antagonize the inflammatory effects of SP.

Potencies of various neurotensin-(8-13) analogs for inhibition of heat-induced edema in the anesthetized rat.

Peptides of the neurotensin (NT) and xenopsin (XP) families inhibit vascular leakage in various models of tissue injury. In this study, we measured the potency of NT fragments, NT analogs and NT-(8-13) analogs for inhibition of thermal edema induced by immersion of the anesthetized rat's paw in 58 degrees C water for 1 min. The pattern of anti-edema potencies seen with sixteen NT-(8-13) analogs correlated well with the pattern of activities obtained in binding measurements to rat brain membrane preparations and to activities in isolated organ preparations. Replacement of Tyr11 with Trp in NT-(8-13) and Arg8 with D-Arg resulted in an analog [D-Arg8, Trp11]NT-(8-13) which was 5-times more potent than NT-(8-13). Substitution of D-Arg for Arg8 and Arg9 in NT-(8-13) produced analogs that retained anti-edema activity but with decreased effects on gut motility and hypotension.

Xenopsin, neurotensin, neurotensin(8-13) and N-acetyl-neurotensin(8-13) inhibit vascular leakage in rats after tissue injury.

Swelling, edema and leakage of proteins from the vascular compartment are immediate inflammatory responses of living tissues to local injury. Xenopsin, neurotensin (NT), NT(8-13) and NAcNT(8-13) administered to male rats anesthetized with sodium pentobarbital 60 mg/kg i.p. inhibited swelling and edema in the paw induced by immersion in 58 degrees water for 1 min. The ED50 values for xenopsin. NT, NAcNT(8-13) and NT(8-13) for reducing heat-induced edema were 0.9, 1.5, 1.9 and 2.1 nmol/kg i.v., respectively. NAcNT(8-13) was chosen as a prototype for further studies because, compared to NT, it had minimal hypotensive effects. NAcNT(8-13), 4 nmol/kg i.v., injected 10 min before mechanical injury to muscle, produced by a 4 cm midline surgical incision in the rectus abdominis, or before freeze injury to the cortex, produced by applying a cold probe (-50 degrees C) to the skull for 4 min, reduced vascular leakage, measured as area of Monastral blue staining of the injured tissues. NAcNT(8-13), 4 nmol/kg i.v., also attenuated pulmonary edema induced by epinephrine bitartrate 10 micrograms/kg i.v. The ability of NAcNT(8-13) to inhibit vascular leakage was not linked to its transient hypotensive effects and it was not blocked by alpha-helical-CRF(9-41), a putative CRF receptor antagonist, or by chlorpheniramine, a H1-histamine receptor antagonist.

Peripheral anti-inflammatory actions of corticotropin-releasing factor.

Swelling, oedema, and loss of fluids and protein from the vascular compartment are immediate responses seen in living tissues after severe injury. Peptides of the corticotropin-releasing factor (CRF) superfamily have the unusual property of preventing the vascular leakage that occurs in tissues after damage. For example, CRF decreased protein extravasation, oedema and swelling in the anaesthetized rat's paw after exposure to heat or to extreme cold, in tracheal mucosa after exposure to formaldehyde, in skeletal muscle after a knife cut, and in brain cortex after freezing. The anti-inflammatory actions of CRF were independent of steroid release or hypotensive effects. CRF was a functional antagonist of inflammatory mediators such as histamine and substance P. It inhibited neurogenic inflammation, but interactions with unmyelinated sensory neurons did not account for the wide range of CRF's anti-inflammatory activities. Localized application of CRF prevented histamine-induced leaks in the hamster cheek pouch, and displaceable binding sites to iodinated CRF were found on blood vessels and on epithelial cells in close proximity to sites of vascular leakage. These results indicated peripheral sites of action. CRF may be the first example of a peptide hormone demonstrated to have potent anti-inflammatory agonist actions in vivo.

Corticotropin-releasing factor inhibition of substance P-induced vascular leakage in rats: possible sites of action.

Substance P (SP), 40 micrograms/kg SC, induced protein leakage in the skin, muscle, trachea and esophagus of the anesthetized rat as measured by Monastral blue B labeling of small blood vessels. CRF, 30 micrograms/kg SC, injected 30 min before SP, decreased the SP-induced dye leakage. To locate where CRF might act, autoradiographic studies of [125I]-CRF binding to esophageal segments were conducted and displaceable binding of [125I]-CRF to submucosal elements in the esophageal epithelium were revealed, suggesting that CRF acts on selective sites to reduce vascular leakage.

Corticotropin-releasing factor: an inhibitor of vascular leakage in rat skeletal muscle and brain cortex after injury.

Corticotropin-releasing factor (CRF) and other peptides of the corticoliberin superfamily inhibit development of edema in skin and mucosa after noxious stimuli. Here, the breadth of CRFs protective activity on small blood vessels was examined after injury to skeletal muscle or to brain cortex. Male rats (243 +/- 15 g) were anesthetized with sodium pentobarbital 60 mg/kg i.p. and Monastral blue 60 mg/kg i.v. was injected 3 min before mechanical injury to muscle produced by a 4 cm midline surgical incision in the rectus abdominis or before freeze injury to the cortex produced by applying a cold probe (-50 degrees C) to the skull for 4 min. Vascular leakage, measured as area of dye staining multiplied by its light intensity, was quantified with an image-analysis system. CRF, having the human/rat sequence, 30 micrograms/kg s.c., injected once (30 min) or twice (30 min and 10 min) before injury to muscle or to brain, inhibited the lesion size by 58% and 55%, respectively (tissues taken at 0.5 and 1 h). Microscopy showed that CRF inhibited Monastral blue labeling of small blood vessels. The ED50 (95% C.L.) of CRF for reducing vascular leakage in muscle after celiotomy was 24 (9 to 64) micrograms/kg s.c. h/rCRF injected 30 micrograms/kg s.c. 2 h before celiotomy inhibited vascular leakage after celiotomy in adrenalectomized rats and this effect was not obtained with dexamethasone phosphate, 1 mg/kg s.c. alpha-Helical CRF (9-41), a CRF receptor antagonist, attenuated the actions of CRF on celiotomy. Laser-Doppler flowmeter measurements of skeletal muscle showed that the anti-inflammatory effects of CRF occurred when there were no significant concurrent changes in blood flow. From these results, we surmise that CRF has a versatile protective effect on small blood vessels when it inhibits leakage within different vascular beds.