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Biomedical subjects

A Luini

Publications and source records attributed to A Luini.

At least 37 records · Page 2Linked to original sources

Very young women (<35 years) with operable breast cancer: features of disease at presentation.

BACKGROUND: Breast cancer rarely occurs in young women. Our knowledge about disease presentation, prognosis and treatment effects are largely dependent upon older series. MATERIALS AND METHODS: We evaluated biological features and stage at presentation for 1427 consecutive premenopausal patients aged < or = 50 years with first diagnosis of invasive breast cancer referred to surgery at the European Institute of Oncology from April 1997 to August 2000. A total of 185 patients (13%) were aged < 35 years ('very young') and 1242 (87%) were aged 35-50 years ('less young'). The expression of estrogen receptors (ER), progesterone receptors (PgR), presence of vascular invasion (VI), grading (G), expression of Ki-67, HER2/neu overexpression, pathological stage according to TNM staging system (pTNM), pathological tumor size and number of axillary lymph node involvement were evaluated. RESULTS: Compared with less young patients, the very young patient group had a higher percentage of tumors classified as ER negative (P < 0.001), PgR negative (P = 0.001), higher expression of Ki-67 > or = 20% of cells stained; 62.2% versus 53%, (P < 0.001), vascular or lymphatic invasion (48.6% versus 37.3%, P = 0.006), and pathological grade 3 (P < 0.0001). There was no difference between the two groups for pT, pathological tumor size (pN) and number of positive lymph nodes. CONCLUSIONS: We conclude that compared with less young premenopausal patients, very young women have a greater chance of having an endocrine-unresponsive tumor, and are more likely to present with a higher grade, more extensively proliferating and vessel invading disease. Pathological tumor size, nodal status and number of positive axillary lymph-nodes have a similar distribution among the younger and the older cohorts, thus not supporting previous data indicating more advanced disease in younger patients at diagnosis of operable disease.

Adult↗

Radioguided occult lesion localisation (ROLL) and surgical biopsy in breast cancer. Technical aspects.

BACKGROUND: The surgical management of non-palpable breast lesions remains controversial. At our Institute we have introduced a new technique, radioguided occult lesion localisation (ROLL) to replace standard methods and overcome their disadvantages. In this paper technical aspects of ROLL and results on a large series of patients are reported. METHODS: We analysed 812 consecutive patients with 816 non-palpable breast lesions detected mammographically or ultrasonically. (99m)Tc-labelled particles of human serum albumin (7-10 MBq) in 0.2 ml saline were injected into the lesion under stereotactic mammographic or ultrasonic guidance. Mammography and scintigraphy were then performed. With ultrasound guidance only scintigraphic control was necessary. The excision biopsy was carried out with the aid of a hand-held gamma-detecting probe, and entire removal of the lesion was verified by X-ray of the specimen. RESULTS: The tracer was correctly positioned initially in 772/816 (94.6%) cases and at second attempt in another 2. In 42/816 (5.1%) cases, lesion localisation had to be repeated using a traditional approach. X-ray demonstrated the lesion was entirely removed in 770/774 (99.5%) cases. Pathological examination revealed 367 (47.4%) benign lesions and 407 (52.6%) cancers. The cancers were treated by conservative breast surgery in 99.5% of cases. CONCLUSIONS: We concluded that ROLL enables the surgeon to remove occult breast lesions easily and reliably.

Adult↗

Small cargo proteins and large aggregates can traverse the Golgi by a common mechanism without leaving the lumen of cisternae.

Procollagen (PC)-I aggregates transit through the Golgi complex without leaving the lumen of Golgi cisternae. Based on this evidence, we have proposed that PC-I is transported across the Golgi stacks by the cisternal maturation process. However, most secretory cargoes are small, freely diffusing proteins, thus raising the issue whether they move by a transport mechanism different than that used by PC-I. To address this question we have developed procedures to compare the transport of a small protein, the G protein of the vesicular stomatitis virus (VSVG), with that of the much larger PC-I aggregates in the same cell. Transport was followed using a combination of video and EM, providing high resolution in time and space. Our results reveal that PC-I aggregates and VSVG move synchronously through the Golgi at indistinguishable rapid rates. Additionally, not only PC-I aggregates (as confirmed by ultrarapid cryofixation), but also VSVG, can traverse the stack without leaving the cisternal lumen and without entering Golgi vesicles in functionally relevant amounts. Our findings indicate that a common mechanism independent of anterograde dissociative carriers is responsible for the traffic of small and large secretory cargo across the Golgi stack.

Animals↗

Histologic detection and clinical implications of micrometastases in axillary sentinel lymph nodes for patients with breast carcinoma.

BACKGROUND: Sentinel lymph node (SLN) biopsy is used increasingly in patients with clinically lymph node negative, early-stage breast carcinoma, because it can spare axillary dissection when the sentinel lymph nodes are negative. The question arises, however, whether complete axillary lymph node dissection (ALND) also is necessary in patients with only micrometastases (< or = 2 mm in greatest dimension) in axillary SLNs. The authors carried out the current study to ascertain the risk of non-SLN axillary metastases in such patients and to assess the detection rate of SLN micrometastases in relation to the sectioning interval and the number of sections examined. METHODS: The authors examined 109 patients with micrometastatic SLNs from a series of 634 patients with carcinoma of the breast who underwent SLN biopsy and complete ALND as part of the surgical treatment for their disease. The SLNs were sectioned completely at 50-microm intervals, and the sections were examined intraoperatively. RESULTS: The overall frequency of metastases in axillary non-SLNs was 21.8%. The frequency was correlated significantly with the size of the SLN micrometastatic focus (P = 0.02): 36.4% of patients with foci > 1 mm had metastases in axillary lymph nodes--a percentage approaching 44.7% of patients with macrometastatic SLNs--whereas only 15.6% of patients with micrometastases < or = 1 mm had other involved axillary lymph nodes. CONCLUSIONS: Outside of clinical trials, patients with T1 and small T2 breast carcinoma and micrometastatic SLNs should undergo complete ALND for adequate staging. However, patients with SLN micrometastases up to 1 mm in greatest dimension have a significantly lower risk of additional axillary metastases, raising the question of whether ALND may be avoided in this subgroup of patients.

Adult↗

A preliminary report of intraoperative radiotherapy (IORT) in limited-stage breast cancers that are conservatively treated.

Local recurrences after breast conserving surgery occur mostly in the quadrant harbouring the primary carcinoma. The main objective of postoperative radiotherapy should be the sterilisation of residual cancer cells in the operative area, while irradiation of the whole breast may be avoided. We have developed a new technique of intra-operative radiotherapy (IORT) of a breast quadrant after the removal of the primary carcinoma. A mobile linear accelerator (linac) with a robotic arm is utilised delivering electron beams able to produce energies from 3 to 9 MeV. Through a perspex applicator, the radiation is delivered directly to the mammary gland and to spare the skin from the radiation, the skin margins are stretched out of the radiation field. To protect the thoracic wall, an aluminium-lead disc is placed between the gland and the pectoralis muscle. Different dose levels were tested from 10 to 21 Gy without important side-effects. We estimated that a single fraction of 21 Gy is equivalent to 60 Gy delivered in 30 fractions at 2 Gy/fraction. Seventeen patients received a dose of IORT of 10 to 15 Gy as an anticipated boost to external radiotherapy, while 86 patients received a dose of 17-19-21 Gy intra-operatively as their whole treatment. The follow-up time of the 101 patients varied from 1 to 17 months (mean follow-up time was 8 months). The IORT treatment was very well accepted by all of our patients, either due to the rapidity of the radiation course in cases where IORT was given as the whole treatment or to the shortening of the subsequent external radiotherapy in cases where IORT was given as an anticipated boost. We believe that single dose IORT after breast resection for small mammary carcinomas may be an excellent alternative to the traditional postoperative radiotherapy. However, a longer follow-up is needed for a better evaluation of the possible late side-effects.

Adult↗

Timing of breast cancer surgery in relation to the menstrual cycle: an update of developments.

It is well-established that hormones have multiple effects on breast cancer. Some, but not all studies indicate that the phase of the menstrual cycle (and hence hormonal status) at the time of breast surgery may influence survival. In this paper we review the literature in this area, explore how it is possible that such an association may occur, and note that randomised studies which unambiguously determined the phase of the cycle at the time of the operation are lacking. We go on to describe an ongoing self-randomised trial designed to address this problem and present preliminary results which show that only about 75% of the women ovulated during the cycle in which the operation took place, and that the established prognostic factor Ki-67 varied with the phase of the cycle in women who ovulated. It is too early to assess the significance of this finding.

Breast Neoplasms↗

Radiotherapy after breast-conserving surgery in small breast carcinoma: long-term results of a randomized trial.

BACKGROUND: Breast-conserving surgery followed by radiotherapy is a widely accepted form of treatment in patients with breast cancer of limited extent. Many attempts have been made to identify subgroups of patients who might avoid radiotherapy. PATIENTS AND METHODS: Between 1987 and 1989, 579 women with carcinoma of the breast were randomly assigned to quadrantectomy, axillary dissection and radiotherapy (299) and to quadrantectomy with axillary dissection without radiotherapy (280). Eligible patients were women with a breast carcinoma less than 2.5 cm in maximum diameter up to 70 years of age. Primary endpoints were intra-breast tumour reappearance (IBTR) and all-cause mortality. RESULTS: The number of IBTRs was significantly higher in patients treated with surgery alone (59 cases out of 273; 10-year crude cumulative incidence of 23.5%) than in patients treated with surgery plus radiotherapy (16 cases out of 294; 10-year crude cumulative incidence of 5.8%). The difference in IBTR frequency between the two treatments appeared to be particularly high in women up to 45 years of age, tending to decrease with increasing age up to no apparent difference in women older than 65 years. Overall survival curves for the two groups, did not differ significantly (P = 0.326). However, a limited survival advantage was evident after radiotherapy for node-positive women. CONCLUSIONS: After breast-conserving surgery radiotherapy appears indicated in all patients up to 55 years of age, in patients with positive axillary nodes, and in patients with extensive intraductal component at histology. The data suggest that radiotherapy may be avoided in patients older than 65, and may be optional in women aged 56-65 years with negative nodes.

Adult↗

The GM130 and GRASP65 Golgi proteins cycle through and define a subdomain of the intermediate compartment.

Integrating the pleomorphic membranes of the intermediate compartment (IC) into the array of Golgi cisternae is a crucial step in membrane transport, but it is poorly understood. To gain insight into this step, we investigated the dynamics by which cis-Golgi matrix proteins such as GM130 and GRASP65 associate with, and incorporate, incoming IC elements. We found that GM130 and GRASP65 cycle via membranous tubules between the Golgi complex and a constellation of mobile structures that we call late IC stations. These stations are intermediate between the IC and the cis-Golgi in terms of composition, and they receive cargo from earlier IC elements and deliver it to the Golgi complex. Late IC elements are transient in nature and sensitive to fixatives; they are seen in only a fraction of fixed cells, whereas they are always visible in living cells. Finally, late IC stations undergo homotypic fusion and establish tubular connections between themselves and the Golgi. Overall, these features indicate that late IC stations mediate the transition between IC elements and the cis-Golgi face.

Animals↗

The Veronesi quadrantectomy: an established procedure for the conservative treatment of early breast cancer.

A little more than 100 years ago Halsted pioneered a surgical approach that led, for the first time, to the cure of breast cancer in some patients. Veronesi's contribution was to offer the same possibility while considerably reducing the mutilation that went with cure. This article reviews the development of the conservative surgical approach in breast cancer and synoptically presents the results of large-scale clinical trials conducted by Veronesi's group in Milan in the 1970s and 1980s to demonstrate the efficacy of quadrantectomy, radiotherapy and axillary dissection (QUART) as conservative treatment for small size breast cancer. These studies set in motion the world-wide trend to conservative surgery in all forms of cancer. The article goes on to describe the surgical procedures of quadrantectomy and complete axillary dissection as developed by Veronesi, and outlines new indications for, and developments of this established conservative technique.

Axilla↗

Correlative light-electron microscopy reveals the tubular-saccular ultrastructure of carriers operating between Golgi apparatus and plasma membrane.

Transport intermediates (TIs) have a central role in intracellular traffic, and much effort has been directed towards defining their molecular organization. Unfortunately, major uncertainties remain regarding their true structure in living cells. To address this question, we have developed an approach based on the combination of the green fluorescent protein technology and correlative light-electron microscopy, by which it is possible to monitor an individual carrier in vivo and then take a picture of its ultrastructure at any moment of its life-cycle. We have applied this technique to define the structure of TIs operating from the Golgi apparatus to the plasma membrane, whose in vivo dynamics have been characterized recently by light microscopy. We find that these carriers are large (ranging from 0.3-1.7 microm in maximum diameter, nearly half the size of a Golgi cisterna), comprise almost exclusively tubular-saccular structures, and fuse directly with the plasma membrane, sometimes minutes after docking to the fusion site.

Animals↗

Visualizing membrane traffic in vivo by combined video fluorescence and 3D electron microscopy.

In studies of dynamic cellular processes, it would be ideal to be able to combine the capability of in vivo fluorescence video microscopy with the power of resolution of electron microscopy (EM). This article describes an approach based on the association of these two techniques, by which an individual intracellular structure can be monitored in vivo, typically through the use of markers fused with green-fluorescent protein, and then analysed by EM and three-dimensional reconstruction methods, resulting in a 'snapshot' of its fine structure at any chosen time in its life cycle. The potential of this approach is discussed in relation to various aspects of cell biology and especially to the question of the morpho-functional organization of the intracellular membrane trafficking pathways.

Animals↗

Use of technetium-99m-labeled colloid albumin for preoperative and intraoperative localization of nonpalpable breast lesions.

BACKGROUND: Management of clinically occult breast lesions is still a major point of debate. Several techniques (eg, skin projection, guidewire localization) have been proposed, but all of them have technical limitations. STUDY DESIGN: The aim of this study was to assess the efficacy of a new method to locate occult breast lesions using technetium-99m (99mTc)-labeled colloid particles of human serum albumin (radioguided occult lesion localization). We studied 647 consecutive patients (mean age 51.3 years; range 25 to 77 years) with nonpalpable breast lesions detected mammographically or by ultrasonography. Within 24 hours before operation, 3.7 MBq (0.1 mCi) of 99mTc-labeled colloid was injected directly into the center of the lesion using stereotactic mammographic guidance (when only microcalcifications were present) or ultrasonographic guidance (for opacities). Excision biopsy was performed with a gamma-detecting probe. After excision, the area was checked for residual radioactivity and the specimen was radiographed to verify complete removal of the lesion. The material was then sent for pathologic examination. The absorbed dose to the inoculated area and the external irradiation to staff were also determined. RESULTS: In all 647 patients, the "hot spot" was located easily and quickly. X-ray and scintigraphy of the specimen verified the presence and centricity of the lesion in all patients but three (99.5%). Pathologic examination revealed 340 cancer lesions (52.6%). Of these patients, 339 (99.7%) were treated by breast-conserving operations and one (0.3%) received a modified radical mastectomy. No major surgical or postoperative complications were encountered. No recurrences were documented during follow-up. The absorbed dose to the breast and other tissue was negligible (0.03 +/- 0.02 mGy/MBq), as was the dose to the surgeon's hands (7.5 +/- 5.0 microSv/h). The latter dose represents 0.015% and 0.002% of the recommended limits of the European Community for the general population and for exposed workers, respectively. CONCLUSIONS: Radioguided occult lesion localization seems to offer a simple and reliable method to locate occult breast lesions with a gamma-detecting probe, allowing complete removal of the lesion in 99.5% of patients. Because of the small quantity of radioactivity, the procedure is safe for both patients and medical staff.

Adult↗

The lysosomal protease cathepsin D is efficiently sorted to and secreted from regulated secretory compartments in the rat basophilic/mast cell line RBL.

Basophils and mast cells contain a peculiar class of inflammatory granules that discharge their content upon antigen-mediated crosslinking of IgE-membrane receptors. The pathways for granule biogenesis and exocytosis in these cells are still largely obscure. In this study we employed the rat basophilic leukemia (RBL)/mast cell line to verify the hypothesis that inflammatory granules share common bioactive molecules and functional properties with lysosomes. We demonstrate that inflammatory granules, as identified by the monoclonal 5G10 antibody (which recognises an integral membrane protein) or by Toluidine Blue staining, have an intralumenal acidic pH, possess lysosomal enzymes and are accessible by fluid-phase and membrane endocytosis markers. In addition, we studied the targeting, subcellular localisation and regulated secretion of the lysosomal aspartic protease cathepsin D (CD) as affected by IgE receptor stimulation in order to obtain information on the pathways for granule biogenesis and exocytosis. Stimulation with DNP-BSA of specific IgE-primed RBL cells led to a prompt release of processed forms of CD, along with other mature lysosomal hydrolases. This release could be prevented by addition of EGTA, indicating that it was dependent on extracellular calcium influx. Antigen stimulation also induced exocytosis of immature CD forms accumulated by ammonium chloride, suggesting the existence of an intermediate station in the pathway for granule biogenesis still sensitive to regulated exocytosis. The targeting of molecules to secretory granules may occur via either a mannose-6-phosphate-dependent or mannose-6-phosphate-independent pathway. We conclude that endosomes and lysosomes in basophils/mast cells can act as regulated secretory granules or actually identify with them.

Animals↗

Regulation of protein sorting at the TGN by plasma membrane receptor activation.

We show that in the rat basophilic leukemia cell line RBL, the physiological stimulation of the IgE receptor or direct activation of PKC leads to the missorting of proteins to the plasma membrane, diverting them from their normal intracellular destination. This is demonstrated for two classes of proteins that are normally targeted to the secretory lysosomes via completely different mechanisms, i.e. proteoglycans and the aspartic protease cathepsin D. In the latter case, normal processing of the enzyme is also affected, leading to secretion of the immature form of cathepsin. The present study shows how completely different sorting mechanisms, such as those for delivering proteoglycans and cathepsin D to secretory lysosomes, might share common regulatory signals and are similarly affected when the levels of these signals are perturbed. Finally, protein kinase C appears to be a major player in the signal transduction pathways, leading to proteoglycan and cathepsin D missorting.

Animals↗

CtBP/BARS induces fission of Golgi membranes by acylating lysophosphatidic acid.

Membrane fission is essential in intracellular transport. Acyl-coenzyme As (acyl-CoAs) are important in lipid remodelling and are required for fission of COPI-coated vesicles. Here we show that CtBP/BARS, a protein that functions in the dynamics of Golgi tubules, is an essential component of the fission machinery operating at Golgi tubular networks, including Golgi compartments involved in protein transport and sorting. CtBP/BARS-induced fission was preceded by the formation of constricted sites in Golgi tubules, whose extreme curvature is likely to involve local changes in the membrane lipid composition. We find that CtBP/BARS uses acyl-CoA to selectively catalyse the acylation of lysophosphatidic acid to phosphatidic acid both in pure lipidic systems and in Golgi membranes, and that this reaction is essential for fission. Our results indicate a key role for lipid metabolic pathways in membrane fission.

Acyl Coenzyme A↗

PDMP blocks the BFA-induced ADP-ribosylation of BARS-50 in isolated Golgi membranes.

We reported that an inhibitor of sphingolipid biosynthesis, D, L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), blocks brefeldin A (BFA)-induced retrograde membrane transport from the Golgi complex to the endoplasmic reticulum (ER) (Kok et al., 1998, J. Cell Biol. 142, 25-38). We now show that PDMP partially blocks the BFA-induced ADP-ribosylation of the cytosolic protein BARS-50. Moreover, PDMP does not interfere with the BFA-induced inhibition of the binding of ADP-ribosylation factor (ARF) and the coatomer component beta-coat protein to Golgi membranes. These results are consistent with a role of ADP-ribosylation in the action of BFA and with the involvement of BARS-50 in the regulation of membrane trafficking.

Adenosine Diphosphate↗