31 research outputs found

    Intrinsic genetic characteristics determine tumor-modifying capacity of fibroblasts: matrix metalloproteinase-3 5A/5A genotype enhances breast cancer cell invasion

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    Background Stromal fibroblasts can contribute to tumor invasion through the release of matrix metalloproteinases (MMPs). Population studies have suggested that single nucleotide polymorphisms (SNPs) in MMP genes influence levels of expression and may be associated with breast cancer risk and with disease progression. This study directly examined the impact of MMP SNP genotype on the ability of host fibroblasts to promote tumor cell invasion. Methods Primary breast fibroblasts were isolated from patients with (n = 13) or without (n = 19) breast cancer, and their ability to promote breast cancer cell invasion was measured in in vitro invasion assays. Fibroblast invasion-promoting capacity (IPC) was analyzed in relation to donor type (tumor or non-tumor patient), MMP-1, MMP-3, and MMP-9 SNP genotype and MMP activity using independent samples t test and analysis of variance. All statistical tests were two-sided. Results Tumor-derived fibroblasts promoted higher levels of invasion than normal fibroblasts (p = 0.041). When IPC was related to genotype, higher levels of IPC were generated by tumor fibroblasts with the high-expressing MMP-3 5A/5A genotype compared with the 5A/6A and 6A/6A genotypes (p = 0.05 and 0.07, respectively), and this was associated with enhanced MMP-3 release. The functional importance of MMP-3 was demonstrated by enhanced invasion in the presence of recombinant MMP-3, whereas reduction occurred in the presence of a specific MMP-3 inhibitor. An inverse relationship was demonstrated between fibroblast IPC and the high-expressing MMP-1 genotype (p = 0.031), but no relationship was seen with MMP-9 SNP status. In contrast, normal fibroblasts showed no variation in IPC in relation to MMP genotype, with MMP-3 5A/5A fibroblasts exhibiting significantly lower levels of IPC than their tumor-derived counterparts (p = 0.04). Conclusion This study has shown that tumor-derived fibroblasts exhibit higher levels of IPC than normal fibroblasts and that the MMP-3 5A/5A genotype contributes to this through enhanced MMP-3 release. Despite a high-expressing genotype, normal fibroblasts do not exhibit higher IPC or enhanced MMP release. This suggests that more complex changes occur in tumor-derived fibroblasts, enabling full expression of the MMP SNP genotype and these possibly are epigenetic in nature. The results do suggest that, in women with breast cancer, a high-expressing MMP-3 genotype may promote tumor progression more effectively

    Chemical Defense by the Native Winter Ant (Prenolepis imparis) against the Invasive Argentine Ant (Linepithema humile)

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    The invasive Argentine ant (Linepithema humile) is established worldwide and displaces native ant species. In northern California, however, the native winter ant (Prenolepis imparis) persists in invaded areas. We found that in aggressive interactions between the two species, P. imparis employs a potent defensive secretion. Field observations were conducted at P. imparis nest sites both in the presence and absence of L. humile. These observations suggested and laboratory assays confirmed that P. imparis workers are more likely to secrete when outnumbered by L. humile. Workers of P. imparis were also more likely to secrete near their nest entrances than when foraging on trees. One-on-one laboratory trials showed that the P. imparis secretion is highly lethal to L. humile, causing 79% mortality. The nonpolar fraction of the secretion was chemically analyzed with gas chromatography/mass spectrometry, and found to be composed of long-chain and cyclic hydrocarbons. Chemical analysis of dissected P. imparis workers showed that the nonpolar fraction is derived from the Dufour's gland. Based on these conclusions, we hypothesize that this chemical defense may help P. imparis to resist displacement by L. humile

    Effect of cryopreservation on sperm apoptotic deoxyribonucleic acid fragmentation in patients with oligozoospermia

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    Objective: To verify of the increase in sperm apoptotic DNA fragmentation during cryopreservation is greater in oligozoospermic patients than in normozoospermic controls.Design: Controlled prospective study.Setting: patients in an academic research environment.Patient(s): Forty-seven patients with oligozoospermia (concentration < 10 x 10(6) sperm/mL) and 30 normozoospermic men.Intervention(s): Sperm cryopreservation using a standard protocol with a test-yolk buffer, glycerol as the cryoprotectant.Main Outcome Measure(s): Rate of apoptotic sperm DNA fragmentation as assessed by the terminal deoxynucleotidyl-mediated deoxyuridine triphosphate nickend labeling (TUNEL) assay, graded in apoptotic or nonapoptotic, before and after cryopreservation.Result(s): An increase in apoptotic DNA fragmentation was observed in all the groups, regardless of sperm concentration. Normozoospermic men presented a smaller rate of apoptotic DNA fragmentation than oligozoospermic patients, both in pre- and postcryopreservation samples. the increase in DNA fragmentation was similar in both groups.Conclusion(s): Cryopreservation induces apoptotic sperm DNA fragmentation in men, regardless of sperm concentration. Men with oligozoospermia present with higher precryopreservation and postcryopreservation apoptotic sperm DNA fragmentation. the increase in DNA fragmentation is similar in both groups.Universidade Federal de São Paulo, Dept Surg, Div Urol, BR-04038032 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Med, Div Nephrol, BR-04038032 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Surg, Div Urol, BR-04038032 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Med, Div Nephrol, BR-04038032 São Paulo, BrazilWeb of Scienc

    Use of honey associated with Ananas comosus (Bromelin) in the treatment of acute irritative cough

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    Abstract Objective: To evaluate the immediate improvement rate of irritative cough in patients treated with the combination of Ananas comosus extract and honey (Bromelin®) compared with the use of honey alone (placebo group). Methods: Pragmatic, double-blind, randomized, parallel-group study with children aged between 2 and 15 years, with irritative cough for at least 24hours. The double-blind assessment of cough was through the number of observed coughing episodes and intensity score for a period of 10minutes of observation. The decrease of one point in the mean total score was considered as a therapeutic effect. Results: There was a reduction in coughing episodes in both groups, as well as in the cough score after 30minutes of drug or honey administration. The change in clinical score above two points, which could indicate marked improvement, occurred in five patients in the bromelin group and only in one in the placebo group, but without significant difference. There were no adverse events. Conclusions: The immediate improvement rate of irritative cough was similar in patients treated with combination of Ananas comosus extract and honey (Bromelin®) compared with the use of honey alone (placebo group). It is possible that honey has a therapeutic effect on mucus and cough characteristics (Clinical Trials: NCT01356693)
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