16 research outputs found
Cooperative antitumor activities of carnosic acid and Trastuzumab in ERBB2+ breast cancer cells
Background: ERBB2 is overexpressed in up to 20\u201330% of human breast cancers (BCs), and it is associated with
aggressive disease. Trastuzumab (Tz), a humanized monoclonal antibody, improves the prognosis associated with
ERBB2-amplified BCs. However, the development of resistance remains a significant challenge. Carnosic acid
(CA) is a diterpene found in rosemary and sage, endowed with anticancer properties. In this in vitro study,
we have investigated whether Tz and CA have cooperative effects on cell survival of ERBB2 overexpressing
(ERBB2+) cells and whether CA might restore Tz sensitivity in Tz-resistant cells.
Methods: We have studied BC cell migration and survival upon CA and Tz treatment. In particular, migration
ability was assessed by transwell assay while cell survival was assessed by MTT assay. In addition, we have performed cell
cycle and apoptosis analysis by high-resolution DNA flow cytometry and annexin-V, resazurin and sytox blue staining by
flow cytometry, respectively. The expression of proteins involved in cell cycle progression, ERBB2 signaling
pathway, and autophagy was evaluated by immunoblot and immunofluorescence analysis. Cellular structures
relevant to the endosome/lysosome and autophagy pathways have been studied by immunofluorescence and
transmission electron microscopy.
Results: We report that, in ERBB2+ BC cells, CA reversibly enhances Tz inhibition of cell survival, cooperatively
inhibits cell migration and induces cell cycle arrest in G0/G1. These events are accompanied by ERBB2 downregulation,
deregulation of the PI3K/AKT/mTOR signaling pathway and up-regulation of both CDKN1A/p21WAF1
and CDKN1B/p27KIP1. Furthermore, we have demonstrated that CA impairs late autophagy and causes derangement of
the lysosomal compartment as shown by up-regulation of SQSTM1/p62 and ultrastructural analysis. Accordingly, we
have found that CA restores, at least in part, sensitivity to Tz in SKBR-3 Tz-resistant cell line.
Conclusions: Our data demonstrate the cooperation between CA and Tz in inhibiting cell migration and survival of
ERBB2+ BC cells that warrant further studies to establish if CA or CA derivatives may be useful in vivo in the treatment
of ERBB2+ cancers
ERBB1- and ERBB2-Positive Medullary Thyroid Carcinoma: A Case Report
Medullary thyroid carcinomas (MTCs) are rare thyroid tumors occurring in both sporadic and hereditary forms, whose pathogenesis is related to RET proto-oncogene alterations. MTCs originate from parafollicular cells, which produce calcitonin that represents the biochemical activity of MTC. Total thyroidectomy is the main treatment for MTC and often cures patients with confined diseases. In the presence of metastasis, the therapeutic approach depends on the rate of disease progression. We report a case of a 54-year-old female with a single, incidentally discovered, thyroid nodule of 1 cm, classified as suspicious MTC after a stimulation test with intravenous (iv) calcium. After surgery, we examined the nodule using immunohistochemistry, immunofluorescence, and electron microscopy. In addition to calcitonin, we found that it expressed intracellular positivity for the tyrosine kinase RTK receptors ERBB1 and ERBB2. Consistently with MTC features, the ultrastructural examination of the tumor displayed heterogeneous spindle-shaped cells containing two groups of secretory granules. Because of the significant correlation found between high ERBB1/ERBB2 levels in MTCs and extrathyroidal growth, the detection of ERBB1 and ERBB2 expression suggests that the two oncoproteins may be involved in the tumor proliferative responses and/or in the differentiation of parafollicular C-cells. The biological, prognostic, and therapeutic significance of these patterns would merit further investigations
Training in laparoscopic surgery: face validity of a low cost virtual simulator
Aim of this study is to investigate the importance of acquiring basic and advanced laparoscopic skills using a virtual reality low cost simulator in laparoscopic surgery in a defined theathre, a Medical Simulation Centre.
The study shows and describes the Medical Simulation Centre in terms of utilization and activities. The article describes also the technical features of the system and its validation process about the basic skills using a primary method: the face validity. It consents to evaluate the structural simulator characteristics through a specific questionnaire, used after the system testing (we have chosen a basic skill training).
A sample of 40 participants was selected: 20 post graduate students, 20 expert surgeons.
The groups were divided into two homogeneous subgroups according to the level of confidence with the use of video games, consolles, smartphones (a questionnaire has been used before the practical phase of training). We analyzed the results of the face validity obtained by comparing the two groups reported impressions. The simulator appears ergonomically satisfactory and its structural features are adapted to the laparoscopic training
A nonfunctioning parathyroid carcinoma misdiagnosed as a follicular thyroid nodule.
Parathyroid carcinoma (PC) is a rare endocrine malignancy. The tumor is mostly functioning, causing severe primary hyperparathyroidism, with high serum calcium and parathyroid hormone (PTH) levels. Nonfunctioning PC is extremely rare. We report a 50-year-old male patient who was referred to our Department for a right thyroid nodule, incidentally detected on carotid Doppler ultrasound scan, with a fine-needle aspiration cytology showing a follicular lesion. At the time of our evaluation, neck ultrasound showed a 1.3 cm right hypoechoic thyroid nodule with irregular margins and the absence of enlarged bilateral cervical lymph nodes. Thyroid function tests were normal. Serum calcium was normal and plasma PTH slightly above the upper limit of the normal range. The patients underwent right lobectomy. The intraoperative frozen-section pathological examination raised the suspicion of a PC. Definitive histology showed a markedly irregular infiltrative growth of the tumor with invasion of the thyroid tissue and cervical soft tissues. Immunostaining for thyroglobulin was negative, whereas staining for chromogranin A and PTH showed a strong reactivity. Based on the microscopic findings and the immunohistochemical profile, the tumor was diagnosed as a PC. Postoperative serum calcium and phosphate levels were in the normal range. One month after surgery, serum calcium and PTH were normal. Neck ultrasound and total body computed tomography scan were negative for local and metastatic disease. Eight months later, serum calcium was normal and plasma PTH level remained around the upper limit of normal range. Neck ultrasound did not show any pathological lesions. This is the first case of a nonfunctioning sporadic PC misdiagnosed prior of surgery as a follicular thyroid nodule. The parathyroid nature of the neck lesion could not be suspected before surgery. Fine-needle aspiration cytology (FNAC) may fail to distinguish a parathyroid tumor from a benign thyroid nodule because at FNAC, parathyroid and thyroid lesions have some morphological similarities. Histological criteria are not always sufficient for the differential diagnosis, which can definitely be established using immunohistochemistry
PUPPET MENTORING: A NEW SIMULATION SCENARIO FOR LEARNING SURGICAL ABILITIES
Surgical simulators are now able to teach in a way that the learning curve of young surgeons can progress in a lab faster than when using other teaching models (cadaveric or animal) or real patients. The impact of surgical simulators is confirmed by the fact that, in the US, standardized training courses are needed to acquire the Board of Surgery certification. The virtual simulator set up at the University of Genoa (eLaparo4D) is based on two key features: a convincing haptic feedback and a limited cost. Nevertheless, the main issue of eLaparo4D is the \u201csimplicity\u201d of the virtual scenario. To improve it, a new model of simulation is proposed in this project: the \u201cpuppet mentoring\u201d, that might enhance its characteristics. The \u201cpuppet mentoring\u201d is based on the
recording of the movements of the surgeon in the real clinical scenario, that are transferred to the virtual machine. The apprentice, in his learning session, could be led through the operation by the simulator itself, in a scenario and in a way is the same of the real one
Bcl-2 phosphorylation by p38 MAPK: Identification of target sites and biologic consequences
The antiapoptotic role of Bcl-2 can be regulated by its phosphorylation in serine and threonine residues located in a nonstructured loop that links BH3 and BH4 domains. p38 MAPK has been identified as one of the kinases able to mediate such phosphorylation, through direct interaction with Bcl-2 protein in the mitochondrial compartment. In this study, we identify, by using mass spectrometry techniques and specific anti-phosphopeptide antibodies, Ser(87) and Thr(56) as the Bcl-2 residues phosphorylated by p38 MAPK and show that phosphorylation of these residues is always associated with a decrease in the antiapoptotic potential of Bcl-2 protein. Furthermore, we obtained evidence that p38 MAPK-induced Bcl-2 phosphorylation plays a key role in the early events following serum deprivation in embryonic fibroblasts. Both cytochrome c release and caspase activation triggered by p38 MAPK activation and Bcl-2 phosphorylation are absent in embryonic fibroblasts from p38 alpha knock-out mice (p38 alpha(-/-) MEF), whereas they occur within 12 h of serum withdrawal in p38 alpha(-/-) MEF; moreover, they can be prevented by p38 MAPK inhibitors and are not associated with the synthesis of the proapoptotic proteins Bax and Fas. Thus, Bcl-2 phosphorylation by activated p38 MAPK is a key event in the early induction of apoptosis under conditions of cellular stress
Bcl-2 Phosphorylation by p38 MAPK: identification of target sites and biologic consequences
The antiapoptotic role of Bcl-2 can be regulated by its phosphorylation in serine and threonine residues located in a nonstructured loop that links BH3 and BH4 domains. p38 MAPK has been identified as one of the kinases able to mediate such phosphorylation, through direct interaction with Bcl-2 protein in the mitochondrial compartment. In this study, we identify, by using mass spectrometry techniques and specific anti-phosphopeptide antibodies, Ser(87) and Thr(56) as the Bcl-2 residues phosphorylated by p38 MAPK and show that phosphorylation of these residues is always associated with a decrease in the antiapoptotic potential of Bcl-2 protein. Furthermore, we obtained evidence that p38 MAPK-induced Bcl-2 phosphorylation plays a key role in the early events following serum deprivation in embryonic fibroblasts. Both cytochrome c release and caspase activation triggered by p38 MAPK activation and Bcl-2 phosphorylation are absent in embryonic fibroblasts from p38 alpha knock-out mice (p38 alpha(-/-) MEF), whereas they occur within 12 h of serum withdrawal in p38 alpha(-/-) MEF; moreover, they can be prevented by p38 MAPK inhibitors and are not associated with the synthesis of the proapoptotic proteins Bax and Fas. Thus, Bcl-2 phosphorylation by activated p38 MAPK is a key event in the early induction of apoptosis under conditions of cellular stress
Bcl-2 phosphorylation by p38 MAPK: Identification of target sites and biologic consequences.
The antiapoptotic role of Bcl-2 can be regulated by its phos- phorylation in serine and threonine residues located in a non- structured loop that links BH3 and BH4 domains. p38 MAPK has been identified as one of the kinases able to mediate such phosphorylation, through direct interaction with Bcl-2 protein in the mitochondrial compartment. In this study, we identify, by using mass spectrometry techniques and specific anti-phos- phopeptide antibodies, Ser87 and Thr56 as the Bcl-2 residues phosphorylated by p38 MAPK and show that phosphorylation of these residues is always associated with a decrease in the antiapo- ptotic potential of Bcl-2 protein. Furthermore, we obtained evi- dence that p38 MAPK-induced Bcl-2 phosphorylation plays a key role in the early events following serum deprivation in embryonic fibroblasts. Both cytochrome c release and caspase activation trig- gered by p38 MAPK activation and Bcl-2 phosphorylation are absent in embryonic fibroblasts from p38- knock-out mice, whereas they occur within 12 h of serum with- drawal in p38--/- MEF; moreover, they can be prevented by p38 MAPK inhibitors and are not associated with the synthesis of the proapoptotic proteins Bax and Fas. Thus, Bcl-2 phosphorylation by activated p38 MAPK is a key event in the early induction of apopto- sis under conditions of cellular stress
Additional file 3: Figure S3. of Cooperative antitumor activities of carnosic acid and Trastuzumab in ERBB2+ breast cancer cells
CA and Tz cooperative inhibition of ERBB2+ cell survival is transient. Blue lines represent cell survival of SKBR-3 and BT474 cells continuously cultured with CA + Tz (cultures #2). Red lines represent cell survival of SKBR-3 and BT474 cells cultured for up to 6d with CA + Tz and for further 8d with control medium (cultures #1). Cell survival is expressed as arbitrary units (A.U.) after exposure of cultures to Alamar Blue for 4 h. The arrow represents the time point at which the medium containing the two drugs was replaced with control medium in cultures #1. Mean values and standard deviation (indicated as vertical bars) from four independent replicates (n = 4) are shown. P < 0.001 (***) (TIFF 817 kb