Leptin Modulates Mitochondrial Function, Dynamics and Biogenesis in MCF-7 Cells.

The adipokine leptin, known for its key role in the control of energy metabolism, has been shown to be involved in both normal and tumoral mammary growth. One of the hallmarks of cancer is an alteration of tumor metabolism since cancerous cells must rewire metabolism to satisfy the demands of growth and proliferation. Considering the sensibility of breast cancer cells to leptin, the objective of this study was to explore the effects of this adipokine on their metabolism. To this aim, we treated the MCF-7 breast cancer cell line with 50 ng/mL leptin and analyzed several features related to cellular and mitochondrial metabolism. As a result, leptin increased cell proliferation, shifted ATP production from glycolysis to mitochondria and decreased the levels of the glycolytic end-product lactate. We observed an improvement in ADP-dependent oxygen consumption and an amelioration of oxidative stress without changes in total mitochondrial mass or specific oxidative phosphorylation (OXPHOS) complexes. Furthermore, RT-PCR and western blot showed an up-regulation for genes and proteins related to biogenesis and mitochondrial dynamics. This expression signature, together with an increased mitophagy observed by confocal microscopy suggests that leptin may improve mitochondrial quality and function. Taken together, our results propose that leptin may improve bioenergetic efficiency by avoiding the production of reactive oxygen species (ROS) and conferring benefits for growth and survival of MCF-7 breast cancer cells.

Genistein modulates proliferation and mitochondrial functionality in breast cancer cells depending on ERalpha/ERbeta ratio.

Breast cancer is the most common malignancy in women of developed countries. The aim of this study was to investigate whether genistein, a soy phytoestrogen, and 17ß-estradiol (E2) could have effects on the cell cycle and mitochondrial function and dynamics. Three human breast cancer cell lines with different estrogen receptor alpha (ERα) and estrogen receptor beta (ERß) ratio were used: MCF-7 (high ERα/ERß ratio), T47D (low ERα/ERß ratio) and MDA-MB-231 (ER-negative). Cell proliferation, cell cycle, mitochondrial functionality, and mitochondrial dynamics parameters were analyzed. E2 and genistein treatment induced cell proliferation and apoptosis inhibition in MCF-7, but not in T47D and MDA-MB-231. Moreover, genistein treatment produced an up-regulation of ERß and a rise in cytochrome c oxidase activity in T47D cells, decreasing the ATP synthase/cytochrome c oxidase ratio. Finally, genistein treatment produced a drop in mitochondrial dynamics only in MCF-7 cells. In summary, the beneficial effects of genistein consumption depend on the ERα/ERß ratio in breast cells. Therefore, genistein treatment produces cell cycle arrest and an improvement of mitochondrial functionality in T47D cells with a low ERα/ERß ratio, but not in MCF-7 (high ERα/ERß ratio) and MDA-MB-231 (ER-negative) ones.

Effect of xanthohumol and 8-prenylnaringenin on MCF-7 breast cancer cells oxidative stress and mitochondrial complexes expression.

Xanthohumol (XN) and 8-prenylnaringenin (8PN) are hop (Humulus lupulus L.) polyphenols studied for their chemopreventive effects on certain cancer types. The breast cancer line MCF-7 was treated with doses ranging from 0.001 to 20 µM of XN or 8PN in order to assess the effects on cell viability and oxidative stress. Hoechst 33342 was used to measure cell viability and reactive oxygen species (ROS) production was determined by 2',7'-dichlorofluorescein diacetate. Catalase, superoxide dismutase, and glutathione reductase enzymatic activities were determined and protein expression of sirtuin1, sirtuin3, and oxidative phosphorylation system (OXPHOS) were done by Western blot. Treatments XN 0.01, 8PN 0.01, and 8PN 1 µM led to a decrease in ROS production along with an increase of OXPHOS and sirtuin expression; in contrast, XN 5 µM gave rise to an increase of ROS production accompanied by a decrease in OXPHOS and sirtuin expression. These results suggest that XN in low dose (0.01 µM) and 8PN at all assayed doses (0.001-20 µM) presumably improve mitochondrial function, whereas a high dose of XN (5 µM) worsens the functionality of this organelle.

Genistein modulates oxidative stress in breast cancer cell lines according to ERα/ERß ratio: effects on mitochondrial functionality, sirtuins, uncoupling protein 2 and antioxidant enzymes.

Genistein is a biologically active isoflavone with estrogenic activity and can be found in a variety of soy products. This natural compound displays a wide array of biological activities, but it is best known for its ability to inhibit cancer progression, especially for hormone-related ones such as breast cancer. Genistein has been shown to bind both the estrogen receptor alpha (ERα) and the estrogen receptor beta (ERß), although it has a higher affinity for the ERß. The ERα/ERß ratio is a prognostic marker for breast tumors, and ERß expression could indicate the presence of tumors more benign in state, whereas ERα indicates malignant tumors. The objective of the present study was to investigate the effects of genistein on oxidative stress and mitochondrial functionality through its interaction with the estrogen receptor in breast cancer cell lines with different ERα/ERß ratios. The lower ERα/ERß ratio T47D cell line showed lower oxidative stress and greater mitochondrial functionality, along with an up-regulation of uncoupling protein 2 and sirtuins. On the other hand, genistein-treated MCF-7 cell line, with the highest ERα/ERß ratio, reported no changes for the control situation. On the whole, our results show different genistein effects depending on ERα/ERß ratio for oxidative stress regulation, mitochondrial functionality, and modulation of UCPs, antioxidant enzymes and sirtuins in breast cancer cell lines. Effects of genistein on oxidative stress and mitochondria could be due at least in part, to a higher ERß presence, but could also be due to up-regulation of ERß caused by the genistein treatment.

GOLD: estrategia mundial para la enfermedad pulmonar obstructiva crónica (EPOC) / GOLD: world-wide strategy for chronic obstructive pulmonary disease (COPD)

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MRI findings in lingual venous malformations.

OBJECTIVES: To describe the plain and enhanced MRI findings of lingual venous malformations and to discuss the importance of contrast medium in the differential diagnosis of high intensity lesions of the tongue on T(2) weighted images. METHODS: The clinical records and MR images of eight patients affected by a lingual venous malformation were retrospectively reviewed. Patients presented with a palpable submucosal bluish-red soft mass in the tongue. MRI examinations were performed on a 0.5 T superconducting unit. Plain and enhanced SE (spin echo) T(1) weighted and FSE (fast spin echo) T(2) weighted images were acquired in axial, sagittal and coronal planes. Axial SPGR (spoiled gradient recalled echo) T(1) weighted images were also obtained before and after intravenous (i.v.) injection of paramagnetic contrast medium. RESULTS: Five of eight venous malformations were located at the tip of the tongue. The other three involved the whole tongue and had an extralingual extent; two extended into the submandibular space and one into the glossoepiglottic valleculae. The largest diameter ranged from 2.5 cm to 8 cm. All lingual venous malformations presented as lobulated masses that were slightly hyperintense or isointense on T(1) weighted images and highly hyperintense on T(2) weighted images with respect to normal tongue and/or surrounding muscles. They showed a slow and homogeneous filling following iv injection of contrast medium. Millimetre-sized hypointense foci and linear hypointense strands were sometimes noticed, which were owing to phleboliths, flow void or septation. CONCLUSION: Knowledge of MRI findings of lingual venous malformations is useful for differential diagnosis with other high intensity lingual lesions on T(2) weighted images. This discrimination is achievable using iv paramagnetic contrast medium.

Intra-articular osteoid osteoma: diagnostic imaging in three cases.

PURPOSE: To report our experience pertaining to three cases of intra-articular osteoid osteoma assessed by means of integrated imaging and review of literature. MATERIALS AND METHODS: Medical records, radiologic and nuclear medicine findings pertaining to three cases of intra-articular osteoid osteoma were retrospectively evaluated and compared with those of surgery. All the patients (2 males, one female; age range 8-38 ys) affected by intra-articular osteoid osteoma respectively of the elbow, tibio-talar joint and hip were evaluated by means of radiographic examination and Magnetic Resonance Imaging (MRI). SE T1-w and T2-w, GRE T2*-w, GRE 3D T1-w and STIR pulse sequences were used and axial, coronal and sagittal images were acquired. Two patients underwent CT scan. One patient underwent skeletal scintigraphy. All the patients underwent surgery. RESULTS: In 2 out of 3 cases plain radiography allowed the radiologist to suspect the presence of the lesion. In the remaining one, plain radiography failed to detect both the nidus and the perilesional osteosclerosis; nevertheless, a small osteochondral erosion of the humeral condyle suggested the presence of joint inflammation, thus leading to further investigation. CT scan well depicted the presence of the nidus and, in one case, the presence of joint effusion. MRI was always able to detect the nidus, which presented as lesion of low to intermediate signal in T1-w images, low signal in the T2-w images in one patient and high signal in the remaining two; in these latter STIR images showed high intensity nidus and edema of neighbouring cancellous bone. Furthermore, in all patients MRI clearly depicted joint effusion. Skeletal scintigraphy demonstrated both the lesion and the inflammatory involvement of neighbouring soft tissue. In all patients histologic specimen confirmed the diagnosis of osteoid osteoma with joint inflammation and synovitis. CONCLUSIONS: According to our results and literature data the pre-surgical diagnosis of osteoid osteoma is very difficult to achieve. Indeed, only the combination of clinical information and radiologic and nuclear medicine findings enables the radiologist to make the right diagnosis.

[Helical CT without contrast media as alternative to other methods in urolithiasis]. / La Tc spirale senza mdc in alternativa alle altre metodiche nella urolitiasi.

PURPOSE: During the last five years the use of unenhanced helical CT (HTC) has been proposed as a preliminary diagnostic approach in patients with typical renal colics or with nonspecific flank pain. The aim of this study was to describe our experience in this field. MATERIAL AND METHODS: 130 consecutive patients (82 men and 48 women, with an average age of 54 years) were studied; 94 of them presented typical renal colics, while 36 presented acute flank pain. The parameters used were: 5-mm-thick sections, a pitch of 1.6, a reconstruction interscan spacing at 3 mm, an examination area extending from the kidneys to the base of the bladder. Depending on the case, examinations were carried out using urography in the instrumental or surgical pretreatment phase, ultrasonography to check urinary dilatation and juxtavesical calculi, pyeloMR, ureteroscopic extraction, surgical operation, extracorporeal lithotripsy, and finally the expulsion of the calculi was checked. RESULTS: 81 cases of urolithiasis, 6 cases of renal abnormalities and other renal pathologies, 23 cases of extraurinary pathologies correlated to the symptoms, 5 cases of extraurinary pathologies not correlated to the symptoms and 15 normal cases, were diagnosed. The results obtained were a) a sensitivity of 96.8%, a specificity of 98.4% and a diagnostic accuracy of 97.6% in identifying ureteral calculi; b) a diagnostic accuracy of 100% in identifying urinary tract dilatation; c) a sensitivity of 100% and a specificity of 96.7% in determining the level of obstruction; d) a sensitivity of 92.9% and a specificity of 100% in determining the cause of obstruction. CONCLUSIONS: Confirming the data in the medical literature, helical CT has yielded for more reliable results than the other procedures in identifying the following: calculi, acute obstruction of the urinary tract and other urinary and extraurinary pathologies correlated to the symptoms. Therefore helical CT, where available, must be accepted as the method of preliminary evaluation in all patients with typical renal colics or with nonspecific flank pain.

Experience of total wrist arthroplasty with silastic implants plus grommets.

The experience with radiocarpal joint reconstruction in rheumatoid arthritis using silastic implants and titanium grommets is reported. Forty-one implants were placed in 36 patients from 1986 to 1992, with a followup of 32 implants in 29 patients ranging from 2.5 years to 8 years. After a brief review of the crucial points of the procedure, including indications and surgical technique, the results were examined using a protocol derived from the one proposed in 1988 for an international multicenter study. The procedure, when correct indications are selected and correct surgical steps are performed, allows predictable results with a satisfying recovery of wrist function. Preservation of wrist function through the years seems enhanced by titanium grommets.

[Chronic osteomyelitis of the long bones: magnetic resonance imaging]. / Osteomielite cronica delle ossa lunghe: aspetti con Risonanza Magnetica.

To investigate MR capabilities in assessing the extent of disease in chronic osteomyelitis of long bones, we examined 6 consecutive patients, 4 men and 2 women (age range: 27-67 years; mean: 42 years), with posttraumatic chronic osteomyelitis diagnosed at clinics, US, CT and radiography. The diagnosis had surgical or bioptical confirmation. MR studies were performed with an 0.5 T superconducting magnet, a surface coil and T1-weighted SE sequences-before and after Gd-DTPA administration-STIR and T2-weighted SE sequences, on the axial and coronal or sagittal planes. The signal intensity of the inflammation area was hypointense on short TR and TE images and hyperintense on long TR and TE images. After Gd-DTPA administration, granulation tissue surrounding the infection was enhanced in all cases and also the areas of vascularized inflammation within bone marrow were enhanced in two cases. MRI provided accurate and detailed information as to soft tissue and medullary canal involvement depicted sinus tracts in 5 cases and confirmed the presence of sequestrum in 5 cases, in agreement with previous CT findings. In our experience, MRI proved to be a reliable tool to assess the intramedullary and extracompartmental extent of osteomyelitis and also to plan surgery. MR specificity, which is often affected by post-traumatic or postoperative changes, improves markedly if some morphological features typical of the condition are also considered, such as sequestrum and sinus tracts.

[Biomechanical correlations of lesions associated with traumatic diseases of the anterior cruciate ligament. Analysis with magnetic resonance]. / Correlazioni biomeccaniche delle lesioni associate alle malattie traumatiche del legamento crociato anteriore. Analisi mediante risonanza magnetica.

To investigate the correlations between traumatic injuries of the anterior cruciate ligament and other ligamentous, meniscal and bone traumatic injuries, a series of 193 patients with anterior cruciate ligament injuries studied with MRI between January 1992 and December 1994, was retrospectively reviewed. MR results were compared with arthroscopic and/or surgical findings in most (181) patients; in the remaining 12 patients, clinical follow-up was performed. We used two 0.5 superconductive MR units, with dedicated coils and T1-weighted spin-echo and T2*-weighted gradient-echo sequences on the axial, sagittal and coronal planes. Anterior cruciate ligament injuries were associated with other ligamentous, meniscal and bone injuries in 78% of patients. The patients were classified in 5 groups depending on biomechanics and the association of injuries: -group I: isolated injury of the anterior cruciate ligament (41 patients), most frequently caused by forced extension stress associated with "kissing contusions" of the anterior portion of the lateral femoral condyle and of the lateral tibial plateau; this type of injury is less frequently caused by forced flexion stress associated with avulsion fracture of the tibial eminence; -group II: associated injury of the anterior cruciate ligament and medial compartment (62 patients), caused by forced flexion-external rotation stress (abduction, valgism and external rotation). The classic association of this mechanism was the injury of the anterior cruciate ligament, medial collateral ligament and medial meniscus (O'Donoghue triad) (9 patients). Valgus stress and the pivot-shift phenomenon can impact the tibial and femoral articular surfaces, with consequent osteochondral contusion; -group III: associated injury of the anterior cruciate ligament and lateral compartment (26 patients), caused by forced flexion-internal rotation stress (adduction, varism and internal rotation). This mechanism can cause, as a typical bone lesion, Segond fractures; -group IV: associated injury of the anterior cruciate ligament, lateral and medial compartments observed in 52 patients with different associations of varus-valgus and rotatory stress; -group V: in 5 patients, anterior cruciate ligament injury was associated with traumatic injury of the posterior cruciate ligament; in this case, posterior displacement of the tibia and knee hyperextension were the most common mechanisms of injury. In conclusion, our results demonstrate that anterior cruciate ligament injuries due to traumatic sprains of the knee are rarely isolated (21%). Thus, it is important to know the biomechanics of knee trauma to read MR images in order to detect possibly associated injuries. The final goal is to assess the actual extent of the traumatic damage for best subsequent clinical-therapeutic management.