RESUMO
The betaretrovirus Mouse Mammary Tumor Virus (MMTV) is the well characterized etiological agent of mammary tumors in mice. In contrast, the etiology of sporadic human breast cancer (BC) is unknown, but accumulating data indicate a possible viral origin also for these malignancies. The presence of MMTVenv-like sequences (MMTVels) in the human salivary glands and saliva supports the latter as possible route of inter-human dissemination. In the absence of the demonstration of a mouse-man transmission of MMTV, we considered the possibility that a cross-species transmission could have occurred in ancient times. Therefore, we investigated MMTVels in the ancient dental calculus, which originates from saliva and is an excellent material for paleovirology. The calculus was collected from 36 ancient human skulls, excluding any possible mouse contamination. MMTV-like sequences were identified in the calculus of 6 individuals dated from the Copper Age to the 17th century. The MMTV-like sequences were compared with known human endogenous betaretroviruses and with animal exogenous betaretroviruses, confirming their exogenous origin and relation to MMTV. These data reveal that a human exogenous betaretrovirus similar to MMTV has existed at least since 4,500 years ago and indirectly support the hypothesis that it could play a role in human breast cancer.
Assuntos
Betaretrovirus/isolamento & purificação , Neoplasias da Mama/virologia , Transformação Celular Viral , Infecções por Retroviridae/transmissão , Infecções Tumorais por Vírus/transmissão , Zoonoses Virais/transmissão , Adolescente , Adulto , Animais , Betaretrovirus/genética , Neoplasias da Mama/história , Neoplasias da Mama Masculina/história , Neoplasias da Mama Masculina/virologia , DNA Viral/genética , Feminino , História do Século XV , História do Século XVI , História do Século XVII , História Antiga , História Medieval , Humanos , Masculino , Vírus do Tumor Mamário do Camundongo/genética , Pessoa de Meia-Idade , Filogenia , Infecções por Retroviridae/história , Infecções por Retroviridae/virologia , Infecções Tumorais por Vírus/história , Infecções Tumorais por Vírus/virologia , Zoonoses Virais/história , Zoonoses Virais/virologia , Adulto JovemRESUMO
A new telemetric system for the electrochemical monitoring of dissolved oxygen is showed. The device, connected with two amperometric sensors, has been successfully applied to the wireless detection of the extracellular oxygen in the central complex of freely-walking Gromphadorhina portentosa. The unit was composed of a potentiostat, a two-channel sensor conditioning circuit, a microprocessor module, and a wireless serial transceiver. The amperometric signals were digitalized and sent to a notebook using a 2.4 GHz transceiver while a serial-to-USB converter was connected to a second transceiver for completing the communication bridge. The software, running on the laptop, allowed to save and graph the oxygen signals. The electronics showed excellent stability and the acquired data was linear in a range comprised between 0 and -165 nA, covering the entire range of oxygen concentrations. A series of experiments were performed to explore the dynamics of dissolved oxygen by exposing the animals to different gases (nitrogen, oxygen and carbon dioxide), to low temperature and anesthetic agents (chloroform and triethylamine). The resulting data are in agreement with previous O2 changes recorded in the brain of awake rats and mice. The proposed system, based on simple and inexpensive components, can constitute a new experimental model for the exploration of central complex neurochemistry and it can also work with oxidizing sensors and amperometric biosensors.
Assuntos
Técnicas Biossensoriais/instrumentação , Baratas/fisiologia , Oxigênio/análise , Tecnologia de Sensoriamento Remoto/instrumentação , Animais , Dióxido de Carbono/metabolismo , Clorofórmio/metabolismo , Baratas/metabolismo , Desenho de Equipamento , Etilaminas/metabolismo , Masculino , Nitrogênio/metabolismo , Software , Caminhada , Tecnologia sem FioRESUMO
BACKGROUND: Most authors have evaluated the location of lower leg arterial perforators, but little is still known about the relationship between the arterial network and great saphenous vein (GSV) and saphenous nerve (SN). The aim of this study is to evaluate the relationship between the arterial network of the posterior tibial artery perforators, the cutaneous nerves, and the superficial venous system in the lower one third of the leg. METHODS: Eighteen lower limbs from cadavers were used for this study. The arterial and venous compartment were selectively injected with a mixture of barium sulfate and epoxy. The specimen were CT scanned and the superficial veins, nerves, and the arterial perforators were dissected. RESULTS: A large perforator of the posterior tibial artery was found at a mean distance of 6.23 cm ± 0.88, with a 95% CI: 5.79-6.67, from the medial malleolus. The average diameter was 0.9 mm ± 0.17, with a 95% CI: 0.81-0.99. In 67% the connection of the venae comitantes to the superficial venous system was established with the GSV, in the other cases, with Leonardo's vein. Both dissection and imaging studies showed perineural interperforator connections along the branches of SN in all the specimens examined. CONCLUSIONS: The distribution pattern of posterior tibial artery perforators followed the superficial nerves in this region. There is an interperforator anastomotic network along the SN. The various patterns of the venous drainage system, in relationship to the distribution of the branches of posterior tibial artery perforators, have been clarified.
Assuntos
Anatomia Regional/métodos , Perna (Membro)/cirurgia , Retalho Perfurante/irrigação sanguínea , Retalho Perfurante/inervação , Veia Safena/inervação , Veia Safena/fisiologia , Tíbia/cirurgia , Artérias da Tíbia/fisiologia , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Cadáver , Dissecação , Feminino , Humanos , Hiperemia/etiologia , Perna (Membro)/irrigação sanguínea , Perna (Membro)/diagnóstico por imagem , Perna (Membro)/inervação , Masculino , Retalho Perfurante/efeitos adversos , Procedimentos de Cirurgia Plástica , Tíbia/irrigação sanguínea , Tíbia/diagnóstico por imagem , Tíbia/inervação , Tomografia Computadorizada por Raios XRESUMO
Metals have strong toxic effects in humans and can act as immunoregulatory factors. The purpose of our study was to determine whether the concentrations of metals are associated with the clinical course of nasal polyposis (NP). We measured the concentrations of 10 metals and non-metal (Zn, Mn, Se, Fe, Cr, Ni, Pb, Al, Cd, and Cu) in 58 patients with NP, and 29 controls with a healthy nasal mucosa. We used electron microscopy to compare the ultrastructural features of the nasal mucosa between NP patients and healthy controls. Concentrations of metals in nasal polyps and healthy mucosa were determined by mass spectrometry. Transmission electron microscopic (TEM) and scanning electron microscopic (SEM) images of the nasal mucosa were obtained. The mean tissue concentrations of all 10 metals and non-metal were significantly lower in NP patients than in healthy controls (P < 0.05).TEM and SEM revealed changes in the mucosal ultrastructure in NP with progressive fibrosis, devascularisation, and inflammation. Tissue concentrations of metals were lower in NP patients than in healthy controls, and this was particularly evident in massive polyposis.
Assuntos
Metais Pesados/análise , Mucosa Nasal/química , Pólipos Nasais/química , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Itália , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Mucosa Nasal/patologia , Pólipos Nasais/patologiaRESUMO
The presence of cancer stem cells (CSCs) or tumor-initiating cells can lead to cancer recurrence in a permissive cell-microenvironment interplay, promoting invasion in glioblastoma (GBM) and neuroblastoma (NB). Extracellular matrix (ECM) small leucine-rich proteoglycans (SLRPs) play multiple roles in tissue homeostasis by remodeling the extracellular matrix (ECM) components and modulating intracellular signaling pathways. Due to their pan-inhibitory properties against receptor tyrosine kinases (RTKs), SLRPs are reported to exert anticancer effects in vitro and in vivo. However, their roles seem to be tissue-specific and they are also involved in cancer cell migration and drug resistance, paving the way to complex different scenarios. The aim of this study was to determine whether the SLRPs decorin (DCN) and lumican (LUM) are recruited in cell plasticity and microenvironmental adaptation of differentiated cancer cells induced towards stem-like phenotype. Floating neurospheres were generated by applying CSC enrichment medium (neural stem cell serum-free medium, NSC SFM) to the established SF-268 and SK-N-SH cancer cell lines, cellular models of GBM and NB, respectively. In both models, the time-dependent synergistic activation of DCN and LUM was observed. The highest DCN and LUM mRNA/protein expression was detected after cell exposure to NSC SFM for 8/12 days, considering these cells as SLRP-expressing (SLRP+) CSC-like. Ultrastructural imaging showed the cellular heterogeneity of both the GBM and NB neurospheres and identified the inner living cells. Parental cell lines of both GBM and NB grew only in soft agar + NSC SFM, whereas the secondary neurospheres (originated from SLRP+ t8 CSC-like) showed lower proliferation rates than primary neurospheres. Interestingly, the SLRP+ CSC-like from the GBM and NB neurospheres were resistant to temozolomide (TMZ) at concentrations >750 µM. Our results suggest that GBM and NB CSC-like promote the activation of huge quantities of SLRP in response to CSC enrichment, simultaneously acquiring TMZ resistance, cellular heterogeneity, and a quiescent phenotype, suggesting a novel pivotal role for SLRP in drug resistance and cell plasticity of CSC-like, allowing cell survival and ECM/niche modulation potential.
Assuntos
Neoplasias Encefálicas/patologia , Proteoglicanas de Sulfatos de Condroitina/fisiologia , Dacarbazina/análogos & derivados , Decorina/fisiologia , Glioblastoma/patologia , Sulfato de Queratano/fisiologia , Células-Tronco Neoplásicas/patologia , Neuroblastoma/patologia , Microambiente Tumoral , Dacarbazina/uso terapêutico , Humanos , Lumicana , TemozolomidaRESUMO
Industrialisation, the proximity of factories to cities, and human work activities have led to a disproportionate use of substances containing heavy metals, such as cadmium (Cd), which may have deleterious effects on human health. Carcinogenic effects of Cd and its relationship with breast cancer, among other tumours, have been reported. 5-Fluorouracil (5-FU) is a fluoropyrimidine anticancer drug used to treat solid tumours of the colon, breast, stomach, liver, and pancreas. The purpose of this work was to study the effects of Cd on cell cycle, apoptosis, and gene and protein expression in MCF-7 breast cancer cells treated with 5-FU. Cd altered the cell cycle profile, and its effects were greater when used either alone or in combination with 5-FU compared with 5-FU alone. Cd significantly suppressed apoptosis of MCF-7 cells pre-treated with 5-FU. Regarding gene and protein expression, bcl2 expression was mainly upregulated by all treatments involving Cd. The expression of caspase 8 and caspase 9 was decreased by most of the treatments and at all times evaluated. C-myc expression was increased by all treatments involving Cd, especially 5-FU plus Cd at the half time of treatment. Cd plus 5-FU decreased cyclin D1 and increased cyclin A1 expression. In conclusion, our results indicate that exposure to Cd blocks the anticancer effects of 5-FU in MCF-7 cells. These results could have important clinical implications in patients treated with 5-FU-based therapies and who are exposed to high levels of Cd.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Cloreto de Cádmio/farmacologia , Interações Medicamentosas , Fluoruracila/farmacologia , Antimetabólitos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Caspase 8/biossíntese , Caspase 9/biossíntese , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina A1/biossíntese , Ciclina D1/biossíntese , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-myc/biossínteseRESUMO
Ultrasound-targeted microbubbles (MBs) offer new opportunities to enhance the capabilities of diagnostic ultrasound (US) imaging to specific pathological tissue. Herein, we report on the design and development of a novel prototype of US contrast agent based on polymeric MBs targeted to prostate-specific membrane antigen (PSMA) for use in the diagnosis of prostate cancer (PCa). First, a set of air-filled MBs by a variety of biocompatible polymers were prepared and characterized in terms of morphology and echogenic properties after exposure to US. MBs derived from poly(D,L-lactic-co-glycolic acid) (PLGA)-poly(ethylene glycol) (PEG) copolymer resulted as the most effective in terms of reflectivity. Such polymer was therefore preconjugated with a urea-based PSMA inhibitor molecular probe (DCL), and the obtained MBs were investigated in vitro for their targeting efficacy toward PSMA positive PCa (LNCaP) cells. Fluorescence microscopy proved a specific and efficient adhesion of targeted MBs to LNCaP cells. To our knowledge, this work reports the first model of polymeric MBs appropriately engineered to target PSMA, which might be further optimized and used for PCa diagnosis and potential carriers for selective drug delivery.
Assuntos
Antígenos de Superfície/metabolismo , Meios de Contraste/química , Glutamato Carboxipeptidase II/metabolismo , Microbolhas , Polímeros/química , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Meios de Contraste/metabolismo , Humanos , Masculino , UltrassonografiaRESUMO
Molecular targeted cancer therapy mediated by nanoparticles (NPs) is a promising strategy to overcome the lack of specificity of conventional chemotherapeutic agents. In this context, the prostate-specific membrane antigen (PSMA) has demonstrated a powerful potential for the management of prostate cancer (PCa). Cancer chemoprevention by phytochemicals is emerging as a suitable approach for the treatment of early carcinogenic processes. Since (-)-epigallocatechin 3-gallate (EGCG) has shown potent chemopreventive efficacy for PCa, we designed and developed novel targeted NPs in order to selectively deliver EGCG to cancer cells. Herein, to explore the recent concept of "nanochemoprevention", we present a study on EGCG-loaded NPs consisting of biocompatible polymers, functionalized with small molecules targeting PSMA, that exhibited a selective in vitro efficacy against PSMA-expressing PCa cells. This approach could be beneficial for high risk patients and would fulfill a significant therapeutic need, thus opening new perspectives for novel and effective treatment for PCa.
Assuntos
Anticarcinógenos/administração & dosagem , Catequina/análogos & derivados , Dipeptídeos/síntese química , Portadores de Fármacos , Nanopartículas , Poliésteres/síntese química , Neoplasias da Próstata/patologia , Anticarcinógenos/química , Anticarcinógenos/farmacologia , Domínio Catalítico , Catequina/administração & dosagem , Catequina/química , Catequina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dipeptídeos/química , Humanos , Cinética , Masculino , Terapia de Alvo Molecular , Poliésteres/química , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/metabolismoRESUMO
BACKGROUND: Development of molecules chemically modifying the expression of crucial orchestrator(s) of stem cell commitment may have significant biomedical impact. We have recently developed hyaluronan mixed esters of butyric and retinoic acids (HBR), turning cardiovascular stem cell fate into a high-yield process. The HBR mechanism(s) remain still largely undefined. METHODOLOGY/PRINCIPAL FINDINGS: We show that in both mouse embryonic stem (ES) cells and human mesenchymal stem cells from fetal membranes of term placenta (FMhMSCs), HBR differentially affected the patterning of Smad proteins, one of the major conductors of stem cell cardiogenesis. Real-time RT-PCR and Western blot analyses revealed that in both cell types HBR enhanced gene and protein expression of Smad1,3, and 4, while down-regulating Smad7. HBR acted at the transcriptional level, as shown by nuclear run-off experiments in isolated nuclei. Immunofluorescence analysis indicated that HBR increased the fluorescent staining for Smad1,3, and 4, confirming that the transcriptional action of HBR encompassed the upregulation of the encoded Smad proteins. Chromatin immune precipitation and transcriptional analyses showed that HBR increased the transcription of the cardiogenic gene Nkx-2.5 through Smad4 binding to its own consensus Smad site. Treatment of mouse ES cells and FMhMSCs with HBR led to the concomitant overexpression of both Smad4 and α-sarcomeric actinin. Smad4 silencing by the aid of lentiviral-mediated Smad4 shRNA confirmed a dominant role of Smad4 in HBR-induced cardiogenesis. CONCLUSIONS/SIGNIFICANCE: The use of HBR may pave the way to novel combinatorial strategies of molecular and stem cell therapy based on fine tuning of targeted Smad transciption and signaling leading to a high-throughput of cardiogenesis without the needs of gene transfer technologies.
Assuntos
Células-Tronco Embrionárias/metabolismo , Ácido Hialurônico/farmacologia , Células-Tronco Mesenquimais/metabolismo , Proteínas Smad/metabolismo , Animais , Western Blotting , Ácido Butírico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células-Tronco Embrionárias/citologia , Ésteres , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Ácido Hialurônico/química , Células-Tronco Mesenquimais/citologia , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/genética , Proteína Smad1/genética , Proteína Smad1/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismo , Tretinoína/farmacologiaRESUMO
The mechanism of formation of the maxillary sinuses is not elucidated as yet, although their morphology during embryogenesis is well described. In the prenatal period, the pneumatization hypothesis is not valid. As the molecular approach to this problem is difficult to apply to human samples, we decided to apply immunohistochemical reactions to analyse the synthesis of selected molecules involved in the rebuilding of tissues. Hematoxylin-eosin staining and immunohistochemical reactions for the detection of MMPs (matrix metalloproteinases), one of their inhibitor TIMP 1 (tissue inhibitor of MMPs), BMP 6 (bone morphogenetic protein 6) and TGF-beta (transforming growth factor beta) were performed in the epithelium the mucosa of the maxillary sinuses of several human foetuses from the collection of the Anatomical Institute. The age of the foetuses was 8, 11, 15, 16, 17, 18 and 22 weeks. An intense positive reaction for MMPs 1, 2 and 3 was found in the mucosal epithehum of developing sinuses in the whole series of foetuses was found. The reaction was more intense in advanced stages of foetal development. Tissue derived inhibitor TIMP was hardly detectable, regardless of the age of samples. However, the intensity of the reaction for TGFbeta was strong in both young and more mature sinus epithelium. The presence of BMP 6, a member of the superfamily of TGFbeta, was detected although the intensity of this reaction in the epithelium was rather weak. Both TGFbeta and BMP 6 are well known as regulators of differentiation in the course of organogenesis. Results of the histochemical analysis suggest the possible involvement of the epithelium in the growth and formation of the maxillary sinuses. The main argument for this is intense reaction for MMP proteases which, as in bone, regulate the turnover and rebuilding processes of the extracellular matrix (ECM).