Laser-activable murine ferritin nanocage for chemo-photothermal therapy of colorectal cancer.

Chemotherapy, as a conventional strategy for tumor therapy, often leads to unsatisfied therapeutic effect due to the multi-drug resistance and the serious side effects. Herein, we genetically engineered a thermal-responsive murine Ferritin (mHFn) to specifically deliver mitoxantrone (MTO, a chemotherapeutic and photothermal agent) to tumor tissue for the chemotherapy and photothermal combined therapy of colorectal cancer, thanks to the high affinity of mHFn to transferrin receptor that highly expressed on tumor cells. The thermal-sensitive channels on mHFn allowed the effective encapsulation of MTO in vitro and the laser-controlled release of MTO in vivo. Upon irradiation with a 660 nm laser, the raised temperature triggered the opening of the thermal-sensitive channel in mHFn nanocage, resulting in the controlled and rapid release of MTO. Consequently, a significant amount of reactive oxygen species was generated, causing mitochondrial collapse and tumor cell death. The photothermal-sensitive controlled release, low systemic cytotoxicity, and excellent synergistic tumor eradication ability in vivo made mHFn@MTO a promising candidate for chemo-photothermal combination therapy against colorectal cancer.

Magnetically modified-mitoxantrone mesoporous organosilica drugs: an emergent multimodal nanochemotherapy for breast cancer.

BACKGROUND: Chemotherapy, the mainstay treatment for metastatic cancer, presents serious side effects due to off-target exposure. In addition to the negative impact on patients' quality of life, side effects limit the dose that can be administered and thus the efficacy of the drug. Encapsulation of chemotherapeutic drugs in nanocarriers is a promising strategy to mitigate these issues. However, avoiding premature drug release from the nanocarriers and selectively targeting the tumour remains a challenge. RESULTS: In this study, we present a pioneering method for drug integration into nanoparticles known as mesoporous organosilica drugs (MODs), a distinctive variant of periodic mesoporous organosilica nanoparticles (PMOs) in which the drug is an inherent component of the silica nanoparticle structure. This groundbreaking approach involves the chemical modification of drugs to produce bis-organosilane prodrugs, which act as silica precursors for MOD synthesis. Mitoxantrone (MTO), a drug used to treat metastatic breast cancer, was selected for the development of MTO@MOD nanomedicines, which demonstrated a significant reduction in breast cancer cell viability. Several MODs with different amounts of MTO were synthesised and found to be efficient nanoplatforms for the sustained delivery of MTO after biodegradation. In addition, Fe3O4 NPs were incorporated into the MODs to generate magnetic MODs to actively target the tumour and further enhance drug efficacy. Importantly, magnetic MTO@MODs underwent a Fenton reaction, which increased cancer cell death twofold compared to non-magnetic MODs. CONCLUSIONS: A new PMO-based material, MOD nanomedicines, was synthesised using the chemotherapeutic drug MTO as a silica precursor. MTO@MOD nanomedicines demonstrated their efficacy in significantly reducing the viability of breast cancer cells. In addition, we incorporated Fe3O4 into MODs to generate magnetic MODs for active tumour targeting and enhanced drug efficacy by ROS generation. These findings pave the way for the designing of silica-based multitherapeutic nanomedicines for cancer treatment with improved drug delivery, reduced side effects and enhanced efficacy.

Cancer Cell Membrane-Biomimetic Nanoparticles Based on Gelatin and Mitoxantrone for Synergetic Chemo-Photothermal Therapy of Metastatic Breast Cancer.

The purpose of this paper is to develop a cancer cell membrane biomimetic nanodrug delivery system (NDDS) to achieve an enhanced chemo-photothermal synergistic antitumor effect. The biomimetic NDDSs are composed of mitoxantrone (MIT)-loaded gelatin nanoparticles and IR820-encapsulated 4T1 cancer cell membrane-derived vesicles. The biomimetic NDDS displayed excellent stability and photothermal conversion efficiency. Compared to naked nanoparticles, the cell membrane-coated nanoparticles improved 4T1 cell uptake through homologous targeting and effectively reduced internalization of macrophages. In vivo photothermal imaging results further showed that the NDDS could be enriched at the tumor site for 48 h and could raise the temperature of the tumor area to 60 °C within 5 min under 808 nm laser irradiation. Finally, NDDS successfully inhibited primary tumor growth (over 89% inhibition) and significantly inhibited lung metastasis. This study may provide a new strategy for personalized chemotherapy-photothermal combination therapy of metastatic breast cancer using tumor cell membranes from cancer patients as drug carriers.

Evaluation of a multiagent chemotherapy protocol combining vincristine, cyclophosphamide, mitoxantrone and prednisolone (CMOP) for treatment of feline intermediate-large cell lymphoma.

OBJECTIVES: The aim of this study was to determine response rates, median progression-free intervals (PFIs) and median survival times (MSTs) for cats with intermediate-large cell lymphoma treated with a vincristine, cyclophosphamide, mitoxantrone and prednisolone (CMOP) protocol. A secondary objective was to determine the tolerability of mitoxantrone used within this multiagent protocol. METHODS: The medical records of 31 cats treated at a single institution between 2009 and 2022 were reviewed to identify suitable cases. Cats were included in the study if they had a confirmed diagnosis of intermediate-large cell lymphoma, had received a CMOP protocol as first-line treatment and had completed at least one 4-week cycle of this protocol. Modifications allowed in the protocol included the use of l-asparaginase, vinblastine substitution for vincristine, chlorambucil substitution for cyclophosphamide and dexamethasone or methylprednisolone substitution for prednisolone. RESULTS: The overall response rate was 74% (n = 23), with 45% (n = 14) achieving complete remission (CR), 29% (n = 9) achieving partial remission (PR) and 26% (n = 8) achieving stable disease (SD). The Kaplan-Meier median PFI and MST were 139 days and 206 days, respectively. Responders (CR or PR) had a significantly longer (P <0.001) median PFI and MST compared with non-responders (SD) (176 days vs 62 days, and 251 days vs 61 days, respectively). Cats that achieved CR had a significantly longer median PFI and MST (P <0.001) at 178 days and 1176 days, respectively. The 6-month and 1- and 2-year survival rates in cats with CR were 64%, 57% and 35%, respectively. Treatment with mitoxantrone was generally well tolerated, with no cats experiencing Veterinary Cooperative Oncology Group adverse effects above grade 2. CONCLUSIONS AND RELEVANCE: The CMOP protocol is an alternative and well-tolerated treatment for cats with intermediate-large cell lymphoma. As demonstrated with previous chemotherapy protocols, cats that respond to treatment, particularly those that achieve CR, are likely to have more durable responses.

Intracerebral haemorrhage in multiple sclerosis: assessing the impact of disease-modifying medications.

Multiple Sclerosis (MS) is a complex autoimmune disorder that significantly impacts the central nervous system, leading to a range of complications. While intracranial haemorrhage (ICH) is a rare but highly morbid complication, more common CNS complications include progressive multifocal leukoencephalopathy (PML) and other CNS infections. This severe form of stroke, known for its high morbidity and mortality rates, presents a critical challenge in the management of MS. The use of disease-modifying drugs (DMDs) in treating MS introduces a nuanced aspect to patient care, with certain medications like Dimethyl Fumarate and Fingolimod showing potential in reducing the risk of ICH, while others such as Alemtuzumab and Mitoxantrone are associated with an increased risk. Understanding the intricate relationship between these DMDs, the pathophysiological mechanisms of ICH, and the individualised aspects of each patient's condition is paramount. Factors such as genetic predispositions, existing comorbidities, and lifestyle choices play a crucial role in tailoring treatment approaches, emphasising the importance of a personalised, vigilant therapeutic strategy. The necessity for ongoing and detailed research cannot be overstated. It is crucial to explore the long-term effects of DMDs on ICH occurrence and prognosis in MS patients, aiming to refine clinical practices and promote patient-centric, informed therapeutic decisions. This approach ensures that the management of MS is not only comprehensive but also adaptable to the evolving understanding of the disease and its treatments.

Intensive Reinduction Chemotherapy Followed by Early Allogeneic Hematopoietic Cell Transplantation for Relapsed/Refractory High-Grade Myeloid Neoplasms.

Outcomes for adults with relapsed/refractory (R/R) high-grade myeloid neoplasms remain poor, with allogeneic hematopoietic cell transplantation (HCT) the sole therapy likely to result in cure. We conducted the present study to determine the feasibility of early HCT-within 60 days of beginning reinduction chemotherapy-to see whether getting patients to HCT in an expeditious manner would expand the number of patients being offered this curative option. In this proof-of-principle feasibility study, we included adults age 18 to 75 years with R/R myeloid malignancies with ≥10% blood/marrow blasts at diagnosis who were eligible for a reduced-intensity HCT. Subjects received reinduction chemotherapy with cladribine, cytarabine, mitoxantrone, and filgrastim (CLAG-M) and proceeded to HCT with reduced-intensity conditioning (fludarabine/ melphalan). We enrolled 30 subjects, all of whom received CLAG-M reinduction, although only 9 underwent HCT within 60 days (<15, the predetermined threshold for feasibility "success"), with a median time to HCT of 48 days (range, 42 to 60 days). Eleven additional subjects received HCT beyond the target 60 days (off-study), with a median time to transplantation of 83 days (range, 53 to 367 days). Barriers to early HCT included infection, physician preference, lack of an HLA-matched donor, logistical delays, and disease progression, all of which may limit the real-world uptake of such early-to-transplantation protocols.

Mitoxantrone and abacavir: An ALK protein-targeted in silico proposal for the treatment of non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is a type of lung cancer associated with translocation of the EML4 and ALK genes on the short arm of chromosome 2. This leads to the development of an aberrant protein kinase with a deregulated catalytic domain, the cdALK+. Currently, different ALK inhibitors (iALKs) have been proposed to treat ALK+ NSCLC patients. However, the recent resistance to iALKs stimulates the exploration of new iALKs for NSCLC. Here, we describe an in silico approach to finding FDA-approved drugs that can be used by pharmacological repositioning as iALK. We used homology modelling to obtain a structural model of cdALK+ protein and then performed molecular docking and molecular dynamics of the complex cdALK+-iALKs to generate the pharmacophore model. The pharmacophore was used to identify potential iALKs from FDA-approved drugs library by ligand-based virtual screening. Four pharmacophores with different atomistic characteristics were generated, resulting in six drugs that satisfied the proposed atomistic positions and coupled at the ATP-binding site. Mitoxantrone, riboflavin and abacavir exhibit the best interaction energies with 228.29, 165.40 and 133.48 KJoul/mol respectively. In addition, the special literature proposed these drugs for other types of diseases due to pharmacological repositioning. This study proposes FDA-approved drugs with ALK inhibitory characteristics. Moreover, we identified pharmacophores sites that can be tested with other pharmacological libraries.

Remission induction versus immediate allogeneic haematopoietic stem cell transplantation for patients with relapsed or poor responsive acute myeloid leukaemia (ASAP): a randomised, open-label, phase 3, non-inferiority trial.

BACKGROUND: Whether high-dose cytarabine-based salvage chemotherapy, administered to induce complete remission in patients with poor responsive or relapsed acute myeloid leukaemia scheduled for allogeneic haematopoietic stem-cell transplantation (HSCT) after intensive conditioning confers a survival advantage, is unclear. METHODS: To test salvage chemotherapy before allogeneic HSCT, patients aged between 18 and 75 years with non-favourable-risk acute myeloid leukaemia not in complete remission after first induction or untreated first relapse were randomly assigned 1:1 to remission induction with high-dose cytarabine (3 g/m2 intravenously, 1 g/m2 intravenously for patients >60 years or with a substantial comorbidity) twice daily on days 1-3 plus mitoxantrone (10 mg/m2 intravenously) on days 3-5 or immediate allogeneic HSCT for the disease control group. Block randomisation with variable block lengths was used and patients were stratified by age, acute myeloid leukaemia risk, and disease status. The study was open label. The primary endpoint was treatment success, defined as complete remission on day 56 after allogeneic HSCT, with the aim to show non-inferiority for disease control compared with remission induction with a non-inferiority-margin of 5% and one-sided type 1 error of 2·5%. The primary endpoint was analysed in both the intention-to-treat (ITT) population and in the per-protocol population. The trial is completed and was registered at ClinicalTrials.gov, NCT02461537. FINDINGS: 281 patients were enrolled between Sept 17, 2015, and Jan 12, 2022. Of 140 patients randomly assigned to disease control, 135 (96%) proceeded to allogeneic HSCT, 97 (69%) after watchful waiting only. Of 141 patients randomly assigned to remission induction, 134 (95%) received salvage chemotherapy and 128 (91%) patients subsequently proceeded to allogeneic HSCT. In the ITT population, treatment success was observed in 116 (83%) of 140 patients in the disease control group versus 112 (79%) of 141 patients with remission induction (test for non-inferiority, p=0·036). Among per-protocol treated patients, treatment success was observed in 116 (84%) of 138 patients with disease control versus 109 (81%) of 134 patients in the remission induction group (test for non-inferiority, p=0·047). The difference in treatment success between disease control and remission induction was estimated as 3·4% (95% CI -5·8 to 12·6) for the ITT population and 2·7% (-6·3 to 11·8) for the per-protocol population. Fewer patients with disease control compared with remission induction had non-haematological adverse events grade 3 or worse (30 [21%] of 140 patients vs 86 [61%] of 141 patients, χ2 test p<0·0001). Between randomisation and the start of conditioning, with disease control two patients died from progressive acute myeloid leukaemia and zero from treatment-related complications, and with remission induction two patients died from progressive acute myeloid leukaemia and two from treatment-related complications. Between randomisation and allogeneic HSCT, patients with disease control spent a median of 27 days less in hospital than those with remission induction, ie, the median time in hospital was 15 days (range 7-64) versus 42 days (27-121, U test p<0·0001), respectively. INTERPRETATION: Non-inferiority of disease control could not be shown at the 2·5% significance level. The rate of treatment success was also not statistically better for patients with remission induction. Watchful waiting and immediate transplantation could be an alternative for fit patients with poor response or relapsed acute myeloid leukaemia who have a stem cell donor available. More randomised controlled intention-to-transplant trials are needed to define the optimal treatment before transplantation for patients with active acute myeloid leukaemia. FUNDING: DKMS and the Gert and Susanna Mayer Stiftung Foundation.

Machine Learning Analysis Using RNA Sequencing to Distinguish Neuromyelitis Optica from Multiple Sclerosis and Identify Therapeutic Candidates.

This study aims to identify RNA biomarkers distinguishing neuromyelitis optica (NMO) from relapsing-remitting multiple sclerosis (RRMS) and explore potential therapeutic applications leveraging machine learning (ML). An ensemble approach was developed using differential gene expression analysis and competitive ML methods, interrogating total RNA-sequencing data sets from peripheral whole blood of treatment-naïve patients with RRMS and NMO and healthy individuals. Pathway analysis of candidate biomarkers informed the biological context of disease, transcription factor activity, and small-molecule therapeutic potential. ML models differentiated between patients with NMO and RRMS, with the performance of certain models exceeding 90% accuracy. RNA biomarkers driving model performance were associated with ribosomal dysfunction and viral infection. Regulatory networks of kinases and transcription factors identified biological associations and identified potential therapeutic targets. Small-molecule candidates capable of reversing perturbed gene expression were uncovered. Mitoxantrone and vorinostat-two identified small molecules with previously reported use in patients with NMO and experimental autoimmune encephalomyelitis-reinforced discovered expression signatures and highlighted the potential to identify new therapeutic candidates. Putative RNA biomarkers were identified that accurately distinguish NMO from RRMS and healthy individuals. The application of multivariate approaches in analysis of RNA-sequencing data further enhances the discovery of unique RNA biomarkers, accelerating the development of new methods for disease detection, monitoring, and therapeutics. Integrating biological understanding further enhances detection of disease-specific signatures and possible therapeutic targets.

Mitoxantrone ameliorates ineffective erythropoiesis in a ß-thalassemia intermedia mouse model.

ABSTRACT: ß-thalassemia is a condition characterized by reduced or absent synthesis of ß-globin resulting from genetic mutations, leading to expanded and ineffective erythropoiesis. Mitoxantrone has been widely used clinically as an antitumor agent considering its ability to inhibit cell proliferation. However, its therapeutic effect on expanded and ineffective erythropoiesis in ß-thalassemia is untested. We found that mitoxantrone decreased α-globin precipitates and ameliorated anemia, splenomegaly, and ineffective erythropoiesis in the HbbTh3/+ mouse model of ß-thalassemia intermedia. The partially reversed ineffective erythropoiesis is a consequence of effects on autophagy as mitochondrial retention and protein levels of mTOR, P62, and LC3 in reticulocytes decreased in mitoxantrone-treated HbbTh3/+ mice. These data provide significant preclinical evidence for targeting autophagy as a novel therapeutic approach for ß-thalassemia.

Un caso de leucemia cutánea / A case of cutaneous leukemia

Leucemia cutánea es una manisfestación extramedular de Leucemia. La frecuencia y edad de distribución depende del subtipo de leucemia1. Usualmente se presenta después que la enfermedad sistémica se ha manifestado y sugiere recaída o resistencia al tratamiento 11,12. Los hallazgos clínicos y morfológicos tienen una amplia variedad de manifestaciones y se pueden presentar en lesiones nodulares y placas. Raras manifestaciones incluyen máculas eritomatosas, ampollas y úlceras que pueden ocurrir solas o en combinación. A partir de una manifestación solitaria o en grupo, la leucemia cutis puede presentarse con rash eritematoso en un patrón clinicamente polimórfico. Consecuentemente , la leucemia cutánea debe distinguirse de diferentes diagnósticos diferenciales como por ejemplo: metástasis cutáneas o malignidades viscerales, linfoma, erupciones por fármacos, infecciones virales, sifilis, úlceras de varios orígenes. En la mucosa oral, hiperplasia gingival es el principal diagnóstico diferencial.1 El conocimiento de la morfologia clinica es de tremenda importancia en casos en donde la Leucemia no fuera conocida.1 Se presenta el caso poco frecuente de una paciente con diagnóstico de leucemia mieloide aguda que desarrolla una leucemia cutánea durante su seguimiento en Consulta Externa...(AU)

Cutaneous leukemia is an extramedullary manifestation of Leukemia. The frequency and age distribution depends on the subtype of leukemia1. It usually occurs after the systemic disease has manifested and suggests relapse or resistance to treatment 11,12. The clinical and morphological findings have a wide variety of manifestations and can occur in nodular lesions and plaques. Rare manifestations include erythematous macules, blisters and ulcers that can occur alone or in combination. From a solitary or group manifestation, leukemia cutis can present with erythematous rash in a clinically polymorphic pattern. Consequently, cutaneous leukemia must be distinguished from different differential diagnoses such as: cutaneous metastases or visceral malignancies, lymphoma, drug eruptions, viral infections, syphilis, ulcers of various origins. In the oral mucosa, gingival hyperplasia is the main differential diagnosis.1 The knowledge of the clinical morphology is of tremendous importance in cases where the Leukemia was not known.1 The rare case of a patient diagnosed with acute myeloid leukemia is presented that develops a cutaneous leukemia during its follow-up in Outpatient Consultation ... (AU)  

Trasplante de médula ósea alogénico en un paciente con fusariosis diseminada y leucemia mieloide aguda / Allogeneic hematopoietic cell transplantation in a patient with disseminated fusariosis and acute myeloid leukemia

La infección diseminada por Fusarium se ha convertido en un problema creciente en las personas con neoplasias hematológicas malignas, principalmente en pacientes con leucemias agudas; se describen cada vez más casos en aquellos sometidos a un trasplante de médula ósea. No existe un tratamiento óptimo establecido para la fusariosis diseminada. La mortalidad global comunicada de esta infección oscila entre el 50 y el 80%. Se presenta a continuación el caso de un paciente de sexo masculino de 29 años, con diagnóstico de leucemia mieloide aguda, que presenta como complicación una fusariosis diseminada, y logra sobrellevar un trasplante alogénico de médula ósea en el Hospital Italiano de San Justo (Argentina) de forma exitosa. (AU)

Disseminated fusariosis has become an increasing problem in people with hematopoietic neoplasms, mainly in patients affected by acute leukemias, and even more in those who undergo hematopoietic cell transplantation. There is not an optimal treatment for disseminated fusariosis. The global mortality described in the literature is between 50% and 80%. We introduce a case of a 29 year old patient with diagnosis of acute myeloid leukemia complicated with disseminated fusariosis, who copes with an allogeneic hematopoietic cell transplantation with a successful outcome in the "Hospital Italiano de San Justo" (Argentina). (AU)

Acute myeloid leukaemia induced by mitoxantrone: case report

Mitoxantrone (MX) é uma agente imunossupressor utilizado nas formas progressivas secundárias de esclerose múltipla (EM) ou formas surto-remissão sem resposta com outras formas de tratamento (p.ex. beta-interferon, acetato de glatirâmer). Com o uso desta medicação, ocorre uma incidência maior, embora pequena, de desenvolvimento de leucemia mielóide aguda induzida por quimioterápicos. Descrevemos o caso de uma paciente com forma progressiva secundária de EM, submetida a uma dose única de MX de 15mg e que 30 meses após desenvolveu quadro fulminante de leucemia promieloblástica aguda (M3), com trombocitopenia grave. A paciente faleceu por hemorragia intracerebral maciça. É feita revisão de outros casos relatados na literatura e os possíveis mecanismos de desenvolvimento desta complicação grave secundária ao uso do MX.

Rabdomiosarcoma embrionario nasal: actualización / Nasal embryonal rhabdomyosarcoma: update

El rabdomiosarcoma no es sólo el sarcoma de tejidos blandos más común en los niños menores de 15 años, sino también en adolescentes y adultos jóvenes. Presentamos el caso de un paciente de sexo masculino de 12 años de edad, quien desarrolló un tumor polipoideo que protruía en la fosa nasal derecha, diagnosticándose rabdomiosarcoma embrionario. Se realiza tratamiento quirúrgico y quimioterápico con muy buen resultado. El paciente después de dos años de su diagnóstico se encuentra libre de enfermedad. Realizamos una revisión de esta variante histopatológica de rabdomiosarcoma, su pronóstico y tratamiento

Nueva combinación terapéutica en cáncer de mama / New combination therapy in breast cancer

Se expone la experiencia 36 pacientes con cáncer de mama tratados con mitoxantrona y metrotexate, seguidos de leucovorina durante 24 horas por vía oral. Se destaca su excelente tolerancia y su efectiva acción citostática

Quimioterapia intraperitoneal no tratamento do câncer do ovário: revisäo da literatura / Intraperitoneal chemotherapy in the management of the ovarian cancer: review of the literature

O artigo revisa a literatura intraperitoneal, com atençäo para a farmacologia das drogas, princípios gerais, abordagem prática as técnicas de administraçäo, os problemas comuns aos dois cateteres mais utilizados, as drogas antineoplásicas disponíveis e a droga de escolha

Esquemas de quimioterapia y bacteriemias en pacientes adultos con leucemia aguda / Chemotherapy schedules and bacteremias in adult patients with acute leukemia

En un estudio efectuado para evaluar la utilidad de la profilaxis con fluoroquinolonas en pacientes neutropénicos afebriles, se encontró una asociación inesperada entre el esquema de poliquimioterapia utilizado y la posterior documentación de bacteriemias durante los episodios de neutropenia y fiebre. Se analizaron 25 episodios de neutropenia febril secundaria a quimioterapia antileucémica. Los pacientes recibieron etoposide y mitoxantrona o bien citarabina - en dosis estándar, intermedia o alta - asociada a daunomicina o mitoxantrona. El análisis de los datos microbiológicos demostró una mayor incidência de bacteriemias con el uso combinado de antraciclinas y citarabina en dosis intermedia o alta en comparación con la administración de etoposide y mitoxantrona (p = 0,000387). Ambos grupos de pacientes desarrollaron una neutropenia igualmente veloz y severa con una mucositis digestiva equivalente. El esquema de poliquimioterapia fue el único dato que se asoció con la aparición o no de bacteriemias en el episodio de neutropenia febril subsiguiente. Se concluye en que otros efectos - además de la aplasia medular y la mucositis digestiva - podrían ser relevantes en la susceptibilidad a las infecciones que originan los citostáticos.

Tratamiento del cáncer avanzado de la glándula mamaria con mitoxantrona, s-fluorouracilo y ciclofosfamida / Advanced breast cancer treatment with a combination of mitoxantrona, s-fluorouracil and ciclophosfamide

La combinación de mitoxantrona (M), 5-fluorouracilo (F) y ciclofosfamida (C), se administró como tratamiento inicial a 180 pacintes con cáncer avanzado de la glándula mamaria. Este estudio no comparativo se llevó a cabo en 7 diferentes instituciones médicas de Argentina, Brasil y México. Las dosis utilizadas fueron: mitoxantrona 12 mg/m2 i.v. día 1-21; 5-fluorouracilo 500 mg'm2 i.v. días 1-8-21 y ciclofosfamida 500 mg/m2 i.v. día 1-21. Las dosis se modificaron de acuerdo a la toxicidad presentada. En el 37% de los 1026 ciclos se presentó leucopenia <2000/mm3 y trombocitopenia <100,000/mm3 en el 16%. Náusea y vómito se presentaron en 82%, diarrea en el 27% y alopecia en el 74%. Respuesta global se observó en 88 de 147 pacientes valorables (60%); respuesta completa en 32 (21.8%) y respuesta parcial en 56 (38%), nos e observaron cambios en 38 (25.9%) y progresión en 21 (14.3%). La sobrevida promedio en este grupo fue de 25 meses; actualmente continúan con vida y sin evidencia de actividad tumoral, a más de 6 años, 24 (16.3%) de las pacientes. Aparte de la mielosupesión, en su mayoría neutropenia, la combinación MFC generalmente fue efectiva y bien tolerada con una baja incidencia de efectos secundarios. Se concluye que mitoxantrona en combinación con 5-fluorouracilo y ciclofosfamida, contribuyen a prolongar la sobrevida de las enfermas con cáncer mamario avanzado, mejorando la calidad de vida en un número importante de ellas. Se recomienda la combinación de MFC como esquema de priemra línea.

Tratamiento del mieloma múltiple refractario o en recaída con mitoxantrona y altas dosis de dexametasona: estudio del mecanismo de resistencia a drogas inducido por glicoproteina-P 170 / Treatment refractory multiple myeloma or in relapse with mitoxantrone and high doses dexamethasone a study of the mechanism of drug resistence induced by P-glycoprotein 170

Treatment of refractory or relapsed multiple myeloma withmitoxantrone and high dose dexamethasone. Study of the mechanism of drug resistance induced by p-glycoprotein 170. One of the most studied mechanism of drug resistance is the induction of a gene (MDR) codifying for a protein (gp-170), which acts by decreasing the intracellular accumulation of various citotoxic drugs. The mechanisms of resistance for mitoxantrone are not yet well understood. As the prognosis of patients with multiple myeloma not responding initially to chemotherapy, or relapsing after achieving a response, is generally poor, the purpose of the present study is to evaluate the activity of mitoxantrone in refractory or relapsed multiple myeloma, as well as to study the ability of this agent to induce drug resistance through the mechanism of p-glycoprotein. Patients will be studied before and at the end of therapy for the expression of p-glycoprotein. Chemotherapy consists of mitoxantrone 12 mg/m²iv, day 1 plus dexamethasone 40 mg iv, daily for 4 days, in six monthly cycles.