The ancient claudin Dni2 facilitates yeast cell fusion by compartmentalizing Dni1 into a membrane subdomain.

Dni1 and Dni2 facilitate cell fusion during mating. Here, we show that these proteins are interdependent for their localization in a plasma membrane subdomain, which we have termed the mating fusion domain. Dni1 compartmentation in the domain is required for cell fusion. The contribution of actin, sterol-dependent membrane organization, and Dni2 to this compartmentation was analysed, and the results showed that Dni2 plays the most relevant role in the process. In turn, the Dni2 exit from the endoplasmic reticulum depends on Dni1. These proteins share the presence of a cysteine motif in their first extracellular loop related to the claudin GLWxxC(8-10 aa)C signature motif. Structure-function analyses show that mutating each Dni1 conserved cysteine has mild effects, and that only simultaneous elimination of several cysteines leads to a mating defect. On the contrary, eliminating each single cysteine and the C-terminal tail in Dni2 abrogates Dni1 compartmentation and cell fusion. Sequence alignments show that claudin trans-membrane helixes bear small-XXX-small motifs at conserved positions. The fourth Dni2 trans-membrane helix tends to form homo-oligomers in Escherichia plasma membrane, and two concatenated small-XXX-small motifs are required for efficient oligomerization and for Dni2 export from the yeast endoplasmic reticulum. Together, our results strongly suggest that Dni2 is an ancient claudin that blocks Dni1 diffusion from the intercellular region where two plasma membranes are in close proximity, and that this function is required for Dni1 to facilitate cell fusion.

Traffic Through the Trans-Golgi Network and the Endosomal System Requires Collaboration Between Exomer and Clathrin Adaptors in Fission Yeast.

Despite its biological and medical relevance, traffic from the Golgi to the plasma membrane (PM) is one of the least understood steps of secretion. Exomer is a protein complex that mediates the trafficking of certain cargoes from the trans-Golgi network/early endosomes to the PM in budding yeast. Here, we show that in Schizosaccharomyces pombe the Cfr1 and Bch1 proteins constitute the simplest form of an exomer. Cfr1 co-immunoprecipitates with Assembly Polypeptide adaptor 1 (AP-1), AP-2, and Golgi-localized, gamma-adaptin ear domain homology, ARF-binding (GGA) subunits, and cfr1+ interacts genetically with AP-1 and GGA genes. Exomer-defective cells exhibit multiple mild defects, including alterations in the morphology of Golgi stacks and the distribution of the synaptobrevin-like Syb1 protein, carboxypeptidase missorting, and stress sensitivity. S. pombe apm1Δ cells exhibit a defect in trafficking through the early endosomes that is severely aggravated in the absence of exomer. apm1Δ cfr1Δ cells exhibit a dramatic disorganization of intracellular compartments, including massive accumulation of electron-dense tubulovesicular structures. While the trans-Golgi network/early endosomes are severely disorganized in the apm1Δ cfr1Δ strain, gga21Δ gga22Δ cfr1Δ cells exhibit a significant disturbance of the prevacuolar/vacuolar compartments. Our findings show that exomer collaborates with clathrin adaptors in trafficking through diverse cellular compartments, and that this collaboration is important to maintain their integrity. These results indicate that the effect of eliminating exomer is more pervasive than that described to date, and suggest that exomer complexes might participate in diverse steps of vesicle transport in other organisms.

The long life of an endocytic patch that misses AP-2.

Endocytosis is the process by which cells regulate extracellular fluid uptake and internalize molecules bound to their plasma membrane. This process requires the generation of protein-coated vesicles. In clathrin-mediated endocytosis (CME) the assembly polypeptide 2 (AP-2) adaptor facilitates rapid endocytosis of some plasma membrane receptors by mediating clathrin recruitment to the endocytic site and by connecting cargoes to the clathrin coat. While this adaptor is essential for early embryonic development in mammals, initial results suggested that it is dispensable for endocytosis in unicellular eukaryotes. The drastic effect of depleting AP-2 in metazoa and the mild effect of deleting AP-2 subunits in Saccharomyces cerevisiae have prevented a detailed analysis of the dynamics of endocytic patches in the absence of this adaptor. Using live-cell imaging of Schizosaccharomyces pombe endocytic sites we have shown that eliminating AP-2 perturbs the dynamics of endocytic patches beyond the moment of coat assembly. These perturbations affect the cell growth pattern and cell wall synthesis. Our results highlight the importance of using different model organisms to address the study of conserved aspects of CME.

Rehabilitación oral integral en un niño con secuela de cirugía de linfangioma de piso de boca y lengua / Integral oral rehabilitation in a child with lymphangioma sequel surgery on floor of the mouth and tongue

Los linfangiomas son malformaciones del desarrollo caracterizadas por una proliferación benigna de los vasos linfáticos y representan hamartomas de los linfáticos malformados y tienen una marcada predilección por la región de la cabeza y el cuello. La localización más frecuente en la boca es el dorso de la lengua, seguido por los labios, la mucosa bucal, el paladar blando y el piso de la boca. Se presenta un caso clínico de una paciente con secuela de cirugías de linfangioma de piso de boca y lengua, con pérdida prematura de piezas dentarias y caries de aparición temprana, y su rehabilitación completa con restauraciones de resina, coronas de celuloide y mantenedores de espacio tipo prótesis parcial superior e inferior...

Lymphangiomas are developmental malformations wich are characterized by a benign proliferation of lymphatic vessels. They represent hamartomas of malformed lymphatics and have a strong predilection for the region of the head and neck. The most common location in the mouth is the dorsum of the tongue, followed by the lips, buccal mucosa, soft palate and fIoor of the mouth. The following case report is of a patient with lymphangioma sequel surgerie on fIoor of mouth and tongue, with premature loss of teeth and early childhood caries, and her complete rehabilitation with resin restorations, strip crowns, and removable space maintainers with artificial tooth...

The tetraspan protein Dni1p is required for correct membrane organization and cell wall remodelling during mating in Schizosaccharomyces pombe.

In fungi, success of mating requires that both cells agglutinate, modify their extracellular envelopes, and fuse their plasma membranes and nuclei to produce a zygote. Here we studied the role of the Schizosaccharomyces pombe Dni1 protein in the cell fusion step of mating. Dni1p is a tetraspan protein bearing a conserved cystein motif similar to that present in fungal claudin-related proteins. Dni1p expression is induced during mating and Dni1p concentrates as discrete patches at the cell-cell contact area and along the mating bridge. Proper Dni1p localization depends on Fus1p, actin and integrity of lipid rafts. In dni1Delta mutants, cell differentiation and agglutination are as efficient as in the wild-type strain, but cell fusion is significantly reduced at temperatures above 25 degrees C. We found that the defect in cell fusion was not associated with an altered cytoskeleton, with an abnormal distribution of Fus1p, or with a defect in calcium accumulation, but with a severe disorganization of the plasma membrane and cell wall at the area of cell-cell contact. These results show that Dni1p plays a relevant role in co-ordinating membrane organization and cell wall remodelling during mating, a function that has not been described for other proteins in the fission yeast.

The Schizosaccharomyces pombe Map4 adhesin is a glycoprotein that can be extracted from the cell wall with alkali but not with beta-glucanases and requires the C-terminal DIPSY domain for function.

SUMMARY: In fungi, cell adhesion is required for flocculation, mating and virulence, and it is mediated by covalently bound cell wall proteins termed adhesins. Map4, an adhesin required for mating in Schizosaccharomyces pombe, is N-glycosylated and O-glycosylated, and is an endogenous substrate for the mannosyl transferase Oma4p. Map4 has a modular structure with an N-terminal signal peptide, a serine and threonine (S/T)-rich domain that includes nine repeats of 36 amino acids (rich in serine and threonine residues, but lacking glutamines), and a C-terminal DIPSY domain with no glycosylphosphatidyl inositol (GPI)-anchor signal. Map4 can be extracted from cell walls with SDS/mercaptoethanol sample buffer or with mild alkali solutions. After extensive extraction with hot sample buffer, no more protein can be released by beta-glucanases or alkali. Additionally, none of the cysteine residues of the protein is required for its retention at the cell wall. These results show that Map4 is not directly bound to beta-glucans and point to the existence of alkali- and SDS/mercaptoethanol-sensitive linkages between cell wall proteins. The N-terminal S/T-rich regions are required for cell wall attachment, but the C-terminal DIPSY domain is required for agglutination and mating in liquid and solid media.

Fijación de radioyodo en huesos maxilares simulando metástasis en pacientes con Carcinoma Diferenciado de Tiroides (CDT): False- Positive images in patients with Differentiated Thyroid Carcinoma. (DTC) / Uptake of 131-I in maxillary bones mimicking salivary glands

En estudios centellográficos con 131I (CCT) para seguimiento, postablación o tratamiento de pacientes portadores de carcinoma diferenciado de tiroides (CDT) se observan frecuentemente en tiempos precoces áreas de captación del radiotrazador en macizo facial. Estas áreas corresponden, generalmente, a glándulas salivares y extremo anterior de mucosa nasal y se mantienen durante las primeras 48 horas y no son observadas generalmente a las 72 horas. Pero con menor frecuencia se presentan otras que persisten durante varias semanas; estas áreas fueron consideradas como posibles retención en glándulas salivares, en tejido tiroideo ectópico en piso de boca, o proteínas yodas entre otras causas. En 1996 Valdivieso y col. (Cong. Arg. Biol. Med. Nuclear, Mar del Plata) y Gutiérrez y col. (SLAT, Chile) consideraron además de las mencionadas posibilidades, que la fijación se podría realizar en hueso maxilar en relación con procesos dentales y esta idea se vio favorecida por dos presentaciones sobre pocos casos que coincidían con la idea sobre el lugar de fijación del radioelemento con producción de imágenes falsas-positivas de enfermedad metastática. Con el propósito de determinar la frecuencia de observación de estas imágenes se procedió a la revisión de 636 CCT efectuados entre el 1 de enero de 2002 y el 31 de diciembre de 2007 en 502 pacientes. En el 31,5 % de los pacientes se observaron áreas activas en maxilares que persistían por varias semanas; la intensidad de concentración fue del 0,3 al 1,2 % de la actividad administrada. En 10 pacientes se efectuaron áreas de interés sobre las zonas activas que se controlaron durante 3 semanas, determinándose el T ½ efectivo registrándose valores promedio de 6,87 ± 0,94 días muy próximos al T ½ físico del 131I, indicando fuerte unión del compuesto radiactivo formado. La intensidad de concentración del radioyodo es variable dependiendo de la intensidad de la lesión dental, (caries, prótesis, pulpitis, granulomas periapicales) y en especial se incrementa en pacientes provenientes del interior que habitaban en zonas con aguas con contenido de flúor o arsénico. Seis pacientes tratados con actividades altas de radioyodo de entre 5,55 y 11,1 MBQ (150 a 300 mCi) mostraron lesiones actínicas en mucosa bucal y lingual. En 5 pacientes se efectuaron inmediatamente después del CCT con radioyodo, estudios panorámicos de Rx maxilar y de centellograma óseo coincidiendo las imágenes maxilares positivas de ambos estudios con las áreas positivas con radioyodo, confirmándose la localización de las mismas. En 13 pacientes que se sometieron a intensos tratamientos odontológicos, en estudios de CCT posteriores se apreció la disminución de intensidad de las imágenes o su desaparición. Ninguno de los pacientes presentó metástasis de CDA en las áreas activas maxilares. Estos hallazgos confirman la concentración del radioyodo en hueso maxilar en relación con alteraciones, dentales debiendo efectuarse investigaciones más profundas sobre la naturaleza de la molécula formada y los mecanismo de fijación de la misma. Deberá tenerse en cuenta el estado de salud dentario del pacientes antes de someterlo a tratamiento de metástasis o ablaciones, en especial cuando las actividades de radioyodo a utilizar sean mayores de 3,7 GBq (100 mCi) y aún indicar tratamiento de las lesiones dentales en forma previa.

In the whole body scans (WBS) with 131I in the follow-up or treatment of patients bearing DTC it is observed frequently fixation areas of the tracer apparently in relation with salivary glands. These areas generally belong to the salivary glands and are present during the first 48/72 hours, but others are kept during more than 3 weeks. These latter ones were considered as possible uptake in ectopic thyroid cells in the mouth floor, iodized proteins, retention of salivary glands and other assertions. Valdivieso et al (Cong. Arg. Biol. Med. Nuclear, 1996) and Gutiérrez et al (SLAT,Chile, 1997) considered that the fixation took place also in maxillary bones probably in areas in relation with dental illness (inflammation, pulpitis, dental caries, perionditis, periapical granuloma, periapical cyst and resorption of surrounding bone seen radiologically as periapical radiolucency). This presumption was sustained for two publications (Clin. Nucl. Med. 1998;23. 747-749, and Clin. Nucl. Med. 2000; 23; 314-315). This end the review of 638 131I WBS carried out between January 1st, 2002 and December 31st of 2007 in 502 patients that were studied for ablation, treatment of metastasis or relapses or follow up. In 31,5% of the patients were observed areas of activity in maxilla. The intensity of concentration of the tracer was 0.3 to 1.2 % of the activity administered. In 10 patients was determinate the effective T ½ and in 5 a panoramic Rx of the maxilla and a bone scintigraphy with 99mTc-MDP; there were correlation between both images, the 131I one an the 99mTc-MDP with radiology. The effective T½ mean value was 6,87 days ± 0,94 (S.D.) very close to the physical T ½ of the radioiodine tracer indicating a strongly labeled molecule. In 6 patients treated with high activities of radioiodine (5,55 to 11,1 MBq - 150 to 300 mCi) actinic lesions were observed in mouth and lingual mucous membrane, including ulcers. The intensity of the images and of the lesions correlate with the intensity of the administered activity of radioiodine, the previous condition of dental integrity and in patients living in the interior of our country in zones of "bad" water containing tracers of arsenic and fluorine. In 13 patients submitted to intense treatment of dental problems posterior WBS showed a decrease of the positive maxilla areas or they were not found. The presence of metastasis in the active maxilla area was in all cases negative. Our observations confirm that radioiodine is deposited in maxillary bone in relation of dental lesions and that this 131I move in a very slow place. This mechanism of fixation has to be determined. We fully recommended taking into account the existence of dental illness or incomplete dental treatments when the administration of higher activities than 3.7 GBq (150 mCi).

Segmentation of pulmonary nodules in thoracic CT scans: a region growing approach.

This paper presents an efficient algorithm for segmenting different types of pulmonary nodules including high and low contrast nodules, nodules with vasculature attachment, and nodules in the close vicinity of the lung wall or diaphragm. The algorithm performs an adaptive sphericity oriented contrast region growing on the fuzzy connectivity map of the object of interest. This region growing is operated within a volumetric mask which is created by first applying a local adaptive segmentation algorithm that identifies foreground and background regions within a certain window size. The foreground objects are then filled to remove any holes, and a spatial connectivity map is generated to create a 3-D mask. The mask is then enlarged to contain the background while excluding unwanted foreground regions. Apart from generating a confined search volume, the mask is also used to estimate the parameters for the subsequent region growing, as well as for repositioning the seed point in order to ensure reproducibility. The method was run on 815 pulmonary nodules. By using randomly placed seed points, the approach was shown to be fully reproducible. As for acceptability, the segmentation results were visually inspected by a qualified radiologist to search for any gross miss-segmentation. 84% of the first results of the segmentation were accepted by the radiologist while for the remaining 16% nodules, alternative segmentation solutions that were provided by the method were selected.

Maintenance of cell integrity in the gas1 mutant of Saccharomyces cerevisiae requires the Chs3p-targeting and activation pathway and involves an unusual Chs3p localization.

Chitin synthase III is essential for the increase in chitin level and for cell integrity in cells lacking Gas1p, a beta(1,3)-glucanosyltransferase. In order to discover whether the upregulation of chitin synthesis proceeds through the canonical transport and activation pathway of Chs3p or through an alternative one, here we studied the effects of the inactivation of the GAS1 and CHS4-5-6-7 genes. All the double-null mutants showed a temperature-sensitive cell lysis phenotype that could be suppressed by the presence of an osmotic stabilizer. In liquid YEPD at 30 degrees C, chs4 delta gas1 delta, chs5 delta gas1 delta, chs6 deltagas1 delta and chs7 delta gas1 delta mutants were unable to grow, whereas they grew very slowly in minimal medium and showed low viability. High osmolarity suppressed the defective phenotype and restored growth. In chs4 gas1, chs5 gas1 and chs7 gas1, chitin levels did not increase and were reduced to only 10%, while in chs6 gas1 the value of gas1 was reduced to 20-40%. To investigate at which level the upregulation of chitin synthesis could occur, mRNA levels were monitored. The expression of CHS4-5-6-7 did not change significantly in gas1 delta. In strains expressing HA-tagged forms, the localization of Chs3p and Chs5p was examined. In the gas1 mutant the fluorescence pattern was affected and the proteins appeared abnormally present in the bud. The results indicate that: (a) the function of the CHS4-7 genes is required for chitin hyperaccumulation in gas1 mutant and for cell integrity; (b) homologous genes do not replace their function; (c) the regulation of CHS4-7 genes does not occur at transcriptional level. Control of the position of chitin synthesis could be important in protecting the bud from lysis.

[Osteosarcoma and brain metastasis]. / Osteosarcoma y metástasis cerebral.

INTRODUCTION: Since the advent of multimodal therapy, survival among patients with osteosarcoma in general and among those with aggressive tumors has improved. Consequently, the pattern of relapse is also changing. Brain metastasis is considered to be a rare event in osteosarcoma, although recent reports suggest that the incidence of this complication may be increasing. CASE REPORT: We report two girls with osteoblastic osteosarcoma of the femur with poor response to preoperative chemotherapy. Both patients developed brain metastasis concurrent with or after the development of lung metastasis. Clinical manifestations of brain metastasis were symptoms of intracranial hypertension in one patient, and a complex partial seizure in the other. DISCUSSION: We advocate periodic neurologic examination and neuroradiologic screening for the early detection of brain involvement in patients whose disease recurs within 1 year of diagnosis, in those with metastasis at diagnosis and in those with a poor histologic response to preoperative chemotherapy.

[Ocular infiltration in the anterior chamber in a female infant with acute non-lymphoblastic leukemia]. / Infiltración de la cámara anterior ocular en una paciente con leucemia no linfoblástica aguda.

Unlike myeloid sarcoma, ocular involvement is unusual in acute non-lymphoblastic leukemia.A 9-month-old female infant with acute non-lymphoblastic leukemia M5 and evidence of active central nervous system (CNS) disease showed infiltration of the anterior chamber during therapy. At that time, the CNS disease was in completed remission. She was treated with topical corticosteroids, chemotherapy and bilateral ocular radiotherapy (total dose 1,000 cGy). The ocular manifestations responded well to treatment but hematologic response was poor. The patient died a few months later. Any ophthalmic manifestation in children with leukemia should be detected and treated early. Radiotherapy is warranted in infiltration of the anterior chamber of the eye. The presence of ocular, central CNS or bone marrow involvement indicates poor prognosis in acute childhood leukemia.

A phase II study of weekly alternating chemotherapy in extensive-stage small cell lung cancer.

Despite the recent development of new chemotherapeutic agents with activity in small cell lung cancer (SCLC), the long-term prognosis of patients with extensive-stage disease remains poor and has not improved in the past 20 years. The present study was designed to evaluate the activity and toxicity of weekly, alternating-regimen chemotherapy in patients with extensive-stage SCLC. Patients with previously untreated extensive-stage SCLC and performance status 0-2 were treated with cyclophosphamide 250 mg/m2, etoposide 100 mg/m2, and cisplatin 50 mg/m2 on day 1; vincristine 1 mg/m2 on day 8; and ifosfamide 1.2 gm/m2 on days 8 and 9 with the entire treatment repeated every 14 days. Eighteen patients received chemotherapy for a median of 14 weeks (range, 1-35 weeks). Seventeen patients (94%) required dose delays and 16 patients (89%) required at least one dose reduction due to toxicity. Twelve patients (67%) exhibited an objective response (1 complete response, 11 partial response) with a median duration of response of 18 weeks (range, 8-32 weeks). Median survival was 33 weeks (range, 1-57 weeks) with a 1-year survival rate of 22%. Toxicity was primarily hematologic, including grade 3-4 leukopenia (82% of patients) and anemia (53% of patients). Only 2 patients developed grade 3 peripheral neuropathy and none exhibited grade 3-4 renal insufficiency. This regimen of weekly alternating combination chemotherapy resulted in tolerable toxicity as well as response and survival rates comparable to those achieved with standard chemotherapy in patients with extensive-stage SCLC. However, weekly chemotherapy regimens for the treatment of SCLC remain investigational.

Chronic oral administration of CI-994: a phase 1 study.

OBJECTIVES: CI-994 (N-acetyl dinaline, PD 123654) is a novel oral agent active in a broad variety of murine and human tumor xenografts. While cytotoxic in the Brown Norway (BN) rat leukemia model, growth inhibition in other murine and human tumor xenografts is predominantly cytostatic. Its specific mechanism of action remains unknown. Following CI-994 administration, inhibition of both histone deacetylation and cellular proliferation at the G1 to S transition phase of the cell cycle are observed. This Phase 1 study in patients with solid tumors was carried out to determine a maximum tolerated daily oral dose (MTD) for CI-994 administered on a chronic basis. METHODS: Fifty-three patients received CI-994 daily for treatment durations ranging from 2 to 10 weeks. Dosage escalation proceeded in 2 phases; an Acute Dosing Phase (n = 11) to define the MTD for CI-994 administered over 2 weeks and a Chronic Dosing Phase (n = 29) to define the MTD for daily administration for 8 weeks. Upon completion of the Chronic Dosing Phase, a third cohort of patients (n = 13) received CI-994 at the recommended Phase 2 dose and schedule with 2 additional single doses of drug administered separated by a 1-week washout to assess the effect of food on CI-994 pharmacokinetics. RESULTS: Thrombocytopenia was dose limiting at the MTD of 8 mg/m2/day for 8 weeks. Other toxicities included fatigue and gastrointestinal effects such as nausea, vomiting, diarrhea, constipation and mucositis. Pharmacokinetic studies revealed that peak plasma levels and AUC's generally increased with dose and that food intake did not affect the rate or extent of drug absorption. One patient with heavily pre-treated adenocarcinoma of the lung achieved a Partial Response (PR) lasting over 2 years and 3 additional patients achieved Stable Disease (SD), 1 each with non-small cell lung, colorectal, and renal cancer. CONCLUSIONS: The recommended Phase 2 starting dose is 8 mg/m2/day for 8 weeks repeated after a 2-week drug-free interval.

[Neurocutaneous melanosis]. / Melanosis neurocutánea.

Neurocutaneous melanosis (NCM) is a rare congenital syndrome characterized by large or multiple congenital melanocytic nevi and excessive proliferation of melanotic cells in the leptomeninges. We report the case of a girl with a giant hairy nevus and numerous small nevi since birth. Within the first 2 years of life she developed clinical features of increased intracranial pressure and West s syndrome. At 2 years of age she presented a right facial palsy and myelopathy. Brain and spinal magnetic resonance imaging demonstrated meningeal infiltration. Diagnosis of NCM was established by a detailed cytologic analyses of the cerebrospinal fluid that revealed melanocytic cells. She received palliative treatment. The girl died 2 months after. Patients with large or multiple congenital melanocytic nevi should be carefully followed up with clinical examination and neuroimaging to detect NCM. At present there is no curative treatment. The association of NCM and West s syndrome has not been previously described.

Chitin synthesis in a gas1 mutant of Saccharomyces cerevisiae.

The existence of a compensatory mechanism in response to cell wall damage has been proposed in yeast cells. The increase of chitin accumulation is part of this response. In order to study the mechanism of the stress-related chitin synthesis, we tested chitin synthase I (CSI), CSII, and CSIII in vitro activities in the cell-wall-defective mutant gas1 delta. CSI activity increased twofold with respect to the control, a finding in agreement with an increase in the expression of the CHS1 gene. However, deletion of the CHS1 gene did not affect the phenotype of the gas1 delta mutant and only slightly reduced the chitin content. Interestingly, in chs1 gas1 double mutants the lysed-bud phenotype, typical of chs1 null mutant, was suppressed, although in gas1 cells there was no reduction in chitinase activity. CHS3 expression was not affected in the gas1 mutant. Deletion of the CHS3 gene severely compromised the phenotype of gas1 cells, despite the fact that CSIII activity, assayed in membrane fractions, did not change. Furthermore, in chs3 gas1 cells the chitin level was about 10% that of gas1 cells. Thus, CSIII is the enzyme responsible for the hyperaccumulation of chitin in response to cell wall stress. However, the level of enzyme or the in vitro CSIII activity does not change. This result suggests that an interaction with a regulatory molecule or a posttranslational modification, which is not preserved during membrane fractionation, could be essential in vivo for the stress-induced synthesis of chitin.

A phase II study of mitomycin C, etoposide, and cisplatin in advanced non-small cell lung cancer.

Standard chemotherapeutic regimens, such as cisplatin and etoposide, may improve quality of life and prolong survival in patients with incurable non-small cell lung cancer (NSCLC). This trial was designed to evaluate the activity and toxicity of a regimen combining three of the most active agents against advanced-stage NSCLC: mitomycin C, etoposide, and cisplatin (MEP). Sixty-eight patients with stage IIIB (pleural effusion) or IV NSCLC received cisplatin 80 mg/m2 i.v. on day 1 and etoposide 80 mg/m2 i.v. on days 1, 2, and 3 every 3 weeks along with mitomycin C 10 mg/m2 i.v. on day 1 of the first and third cycles for a median of four cycles (range, 1-11). Median age was 59 years, and nine patients were enrolled after relapse from previously treated early-stage NSCLC. Eighty-eight percent of patients had stage IV disease, and 14 (21%) had brain metastases at diagnosis. Palliative radiotherapy was given to 10 patients (15%) before MEP and to 17 (25%) concurrent with MEP. The major toxicity of MEP was myelosuppression, with grade 3-4 neutropenia in 74% of patients. Sixteen patients (24%) had documented infections, and there were eight (12%) treatment-related deaths. Partial response was observed in 24 patients (35%) with a median duration of 4.4 months, (range 1.4-13 months). Median survival was 8.1 months (range, 1-34 months), and 1-year survival was 32%. The addition of mitomycin C to cisplatin and etoposide resulted in response and survival rates comparable with those achieved with standard regimens in patients with advanced NSCLC but was associated with substantial hematologic toxicity and unacceptable treatment-related mortality.

Etoposide-induced pulmonary toxicity.

After treatment with etoposide, two patients with lung cancer developed interstitial infiltrates and respiratory failure. Of the two, one patient responded rapidly to steroid therapy and developed recurrent symptoms on re-challenge with etoposide. Both patients had histopathologic findings consistent with drug-induced pulmonary toxicity. Etoposide-induced lung disease needs to be considered in patients who develop subacute dyspnea and interstitial infiltrates during treatment with this agent.

Phase I trial of concurrent thoracic radiation and continuous infusion cisplatin and etoposide in stage III non-small cell lung cancer.

OBJECTIVE: Although combined modality therapy appears to be superior to radiotherapy alone for the treatment of locally advanced non-small cell lung cancer (NSCLC), the optimal treatment regimen has not been determined. We designed this trial to determine the maximal tolerated doses (MTD) of continuous intravenous infusion (CI) cisplatin and etoposide that could be administered concurrently with thoracic irradiation. METHODS: 19 patients with stage IIIA or IIIB NSCLC were treated at three different dose levels of CI cisplatin and etoposide with concurrent single daily fraction thoracic radiotherapy to 4500 cGy. This chemoradiotherapy phase of treatment was followed by a 1500-2000 cGy radiotherapy boost and three cycles of standard intermittent bolus cisplatin 80 mg/m2 i.v. on day 1 and etoposide 80 mg/m2 i.v. on days 1, 2 and 3. RESULTS: The MTD of CI chemotherapy was determined to be cisplatin 5 mg/m2/day plus etoposide 18 mg/m2/day for 5 days per week over 5 weeks along with thoracic irradiation. Overall, 37% of patients required breaks in the chemoradiotherapy course and 32% required attenuation of the planned duration of CI chemotherapy. Only 42% of patients received all three planned cycles of bolus chemotherapy and 16% received < 6000 cGy of thoracic irradiation. The major toxicities during concurrent chemoradiotherapy were grade 3-4 esophagitis (42%) and myelosuppression (47%). Subsequent chemotherapy was complicated by grade 3-4 myelosuppression in 38% of patients. An objective response was documented in 58% of patients (CR 11%, PR 47%). Median survival was 18 months with 2- and 5-year survival rates of 42 and 11%, respectively. CONCLUSIONS: These results demonstrate that CI cisplatin and etoposide can be administered safely to patients with locally advanced NSCLC, and that such potentially radiosensitizing strategies deserve further evaluation in this setting.