Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytostatic chemotherapy instead of supralethal total body irradiation (TBI) has been increasingly used as an alternative myeloablative regimen before bone marrow transplantation (BMT). While irreversible azoospermia/amenorrhoea seems to occur less frequently with such conditioning, graft-versus-host disease (GVHD) remains unaffected. Five-year disease-free survival in accelerated chronic granulocytic leukemia (CGL), after BMT with matched sibling grafts has been 0.10-0.30. Mitobronitol, cytosine arabinoside, and cyclophosphamide were used for conditioning. Patients were transplanted with unmanipulated HLA/MLC identical sibling bone marrow. For recovery, a pathogen-low room was available without air filtering and laminar airflow. Seven of eight accelerated-CGL patients were engrafted: full allogeneic reconstitution was detected in four and mixed chimerism in three patients. Five out of the seven engrafted patients survived at least nine months (median = 42 months), two are considered cured (8-9 years survival). The four leukemia-free survivors displayed full allogeneic reconstitution and presented symptoms of chronic GVHD. One patient became a genetically verified father. Acute GVHD and veno-occlusive liver disease (VOLD) were absent in all patients, diffuse interstitial pneumonitis (IP) occurred in one case. Non-supralethal conditioning with mitobronitol/cytarabine/cyclophosphamide in accelerated-CGL allows allogeneic bone marrow reconstitution with survival and cure rates comparable to those achieved with other protocols using TBI or busulphan conditioning. Unlike the latter treatments, however, our protocol leads to fewer transplant-related complications including acute GVHD, IP, VOLD, and azoospermia/amenorrhoea.
Leukemia 1993 Jul
PMID:Non-supralethal mitobronitol/cytarabine/cyclophosphamide conditioning without irradiation before bone marrow transplantation for accelerated chronic granulocytic leukemia: apparent absence of acute graft-versus-host disease. 832 Oct 45

The major challenge for this generation of children's cancer specialists is to sustain the significant improvement in survival rates, while at the same time minimising treatment-induced late adverse effects. The available evidence suggests that, following first line treatment of acute lymphoblastic leukaemia (ALL), current treatment regimens used in the UK are unlikely to cause sterilisation in either gender. For men who are treated for Hodgkin's disease with 6 or more courses of antineoplastic therapy, azoospermia is the rule. Childhood studies have clearly indicated that the prepubertal testis is not protected from antineoplastic therapy that is potentially sterilising. The interpretation of tests of ovarian function in women treated for cancer in childhood is difficult, but there is increasing evidence of ovarian dysfunction in children treated for Hodgkin's disease. Reassuringly there is no evidence of an increased risk of miscarriage following antineoplastic therapy or an increased number of abnormalities in the offspring. The growth patterns and requirement for growth hormone replacement therapy in children treated for ALL are still unclear. There is good evidence that the intensity and duration of combination cytotoxic antineoplastic therapy received by children with ALL influences the pattern of growth, and that adjuvant antineoplastic therapy for children treated for a brain tumour is an important factor in final height achieved. A child who has been treated for cancer should not be discharged from follow-up. Late effects may have significant implications in later life, and an understanding of these effects is essential to enable balanced decisions to be made regarding the benefits and risks of currently available agents.
 ...
PMID:Late effects of antineoplastic therapy in childhood on growth and endocrine function. 894 94

The improved survival in recent years of young males suffering from cancer, and an understanding of the gonadotoxic effects of chemotherapy treatment, have motivated patients and clinicians to preserve fertility potential before embarking on adjuvant therapy. Among 231 men (mean age 28.0; range 15-56 years) diagnosed with malignant disease and referred to our unit for semen cryopreservation, 112 patients (49.8%) had reduced sperm quality of <10 x 10(6) motile spermatozoa per ejaculate; however, most had sufficient suitable spermatozoa for freezing. In 40 patients (17.3 %) the semen samples were not frozen because of complete azoospermia (n = 32) or only immotile sperm in the ejaculate (n = 2), while six men were unable to produce a single sample. Some 79 men had testicular tumours (group I), 121 suffered from haematological malignancy (leukaemia or lymphoma; group II), and 27 had cancer of different causes (group III). Men in group I had significantly lower (P < 0.001) sperm quality compared with groups II and III. There was no difference between patients with seminoma and non-seminoma tumours. In the haematological malignancy group there was no difference in sperm parameters between leukaemia (n = 12) and lymphoma (n = 77) patients, but patients with Hodgkin's lymphoma had significantly lower sperm quality compared with non-Hodgkin's lymphoma. Following chemotherapy, six couples attended the clinic for assisted conception treatment using the frozen semen. Two had successful intrauterine insemination cycles which each resulted in delivery of a healthy girl; one couple had conceived in their first in-vitro fertilization (IVF) attempt, followed by delivery of healthy twins. Two women conceived after intracytoplasmic sperm injection treatment and the sixth woman achieved only biochemical pregnancy after numerous IVF and frozen embryo replacement cycles. We recommend that a properly designed programme for semen cryopreservation for cancer patients should be developed in leading tertiary assisted conception centres, which have adequate facilities and experience for cryopreservation and can offer the whole range of appropriate assisted reproductive treatment and counselling.
 ...
PMID:A programme of semen cryopreservation for patients with malignant disease in a tertiary infertility centre: lessons from 8 years' experience. 985 91

110 children with malignant diseases (leukemia excepted) who survived 5-20 years (median 9) post-therapy were followed (1996-1998). Median age during follow-up was 15 years (range 5-23). The most common malignancies were brain tumors, lymphoma, retinoblastoma and Wilm's tumor. The 174 late side-effects included endocrine disorders (19%), cognitive impairment (14%), orthopedic dysfunction (12%), alopecia (12%), dental damage (11%), psychological (8%) and neurological (8%) disturbances, and azoospermia or amenorrhea (5%). There was no cardiac or renal damage and no second malignancy. 29% of side-effects were severe. There was significant reduction in quality of life in 54 (49%), in 27 of whom it was severe enough to require psychological intervention. Treatment of brain tumor caused 98 late side-effects in 28 patients (sequelae-to-patient ratio [SPR] 3.3). Most cognitive, endocrine and neurological disorders, and most cases of alopecia, dental and psychological difficulties were in these patients. There were frequent late complications in those treated for retinoblastoma (SPR 1.8), and bone or soft tissue sarcomas (SPR 0.8). Those treated for Wilm's tumor had few side-effects (SPR 0.4). Late side effects were most frequent after radiation, reaching as high as SPR 2.4. It averaged only 0.5 in those treated with chemotherapy alone or in combination with surgery. Reduction of late side-effects in these patients requires using less toxic modalities, as long as cure rate is not compromised. When considering secondary strategies, screening for early detection of late complications would enable immediate solutions, such as hormonal replacement or providing compensating skills for post-treatment disability.
 ...
PMID:[Long-term sequelae of malignant tumors in childhood: consequences of late side-effects]. 1124 36

Testicular cancer is the most common solid tumour among young males aged 15-35 years. Cisplatin-based combination chemotherapy has changed the outlook of this disease. Disseminated testicular cancer, once uniformly fatal, now has a cure rate of more than 80% with combination chemotherapy. Systematic randomised trials have shown that cisplatin, etoposide and bleomycin (PEB) combination chemotherapy remains the mainstay of treatment. While there is a high cure rate with chemotherapy in patients with this disease, some long-term complications from chemotherapy have now been recognised, including secondary leukaemia, therapy-related solid tumours, nephrotoxicity, neurotoxicity, pulmonary toxicity, vascular toxicity and infertility. Etoposide, a DNA topoisomerase II inhibitor, is a significant risk factor for developing leukaemia; the risk appears to be correlated with the total dose given. Patients receiving cisplatin-based combination chemotherapy for testicular cancer also appear to have a higher relative risk for developing second non-germ cell malignancies; the greatest risks for therapy-related solid tumours were seen with a combination of radiation therapy plus chemotherapy. Long-term vascular toxicities associated with chemotherapy include Raynaud's phenomenon, acute myocardial infarction and cerebrovascular events. Bleomycin is thought to be the most important drug in the pathogenesis of Raynaud's phenomenon, while cisplatin is the most likely agent involved in myocardial infarction. Peripheral neuropathy is the most common form of neurotoxicity observed with cisplatin-based chemotherapy. Risk factors for the development of neural damage include a high cumulative dose of cisplatin, the use of vinblastine and the concomitant development of Raynaud's phenomenon. Cisplatin is also well known to cause significant nephrotoxicity. Approximately 25% of patients present with azoospermia after undergoing combination chemotherapy with a follow up of 2-5 years. Physician awareness of complications associated with chemotherapy is vital to maximise efficacy, minimise toxicity, and preserve quality of life after treatment. Sperm cryopreservation should be considered for patients who desire children. Close monitoring during therapy allows for the early diagnosis of complications, and close follow up of patients after the completion of therapy is necessary to monitor for relapse and development of long-term complications such as myelodysplastic syndrome and leukaemia. Despite these complications, given the potential for cure rates in this young group of patients, the benefits far outweigh the risks.
 ...
PMID:Long-term complications of chemotherapy for germ cell tumours. 1288 63

The importance of cryopreserving semen for young male cancer patients is illustrated in three case descriptions. A 28-year-old man with chronic myeloid leukaemia that resulted in azoospermia, later fathered a child with his semen that had been stored prior to chemotherapy. In an 18-year-old adolescent with non-Hodgkin lymphoma the possibility to store cryopreserved semen was only raised after chemotherapy had been started and had caused azoospermia. This caused the patient serious regret. A 14-year-old boy with acute lymphatic leukaemia had his semen stored despite initial hesitations due to his young age. The cancer hardly ever affects the semen quality to the extent that cryopreservation of the semen becomes impossible. The aim should be to obtain several ejaculates prior to the cancer therapy and to store multiple portions, so that later a number of fertilisation attempts are possible. The primary attending physician is initially responsible for raising the possibility of semen cryopreservation. Ideally, however, all health professionals involved should be aware of this aspect. There is a need for multidisciplinary protocols for oncology centres and sperm banks, so that the timely informing of patients is guaranteed, responsibilities are recorded--with appropriate procedures to prevent unnecessary delay--and procedures that concur with legal requirements and financial constraints are established.
 ...
PMID:[Cryopreservation of semen of adolescents and young adult men with cancer]. 1552 35

We analyzed the TS-2 acute lymphoblastic leukemia (ALL) cell line that contains a t(1;19)(q23;p13.3) but lacks E2A-PBX1 fusion typically present in leukemias with this translocation. We found that the t(1;19) in TS-2 fuses the 19p13 gene DAZAP1 (Deleted in Azoospermia-Associated Protein 1) to the 1q23 gene MEF2D (Myocyte Enhancer Factor 2D), leading to expression of reciprocal in-frame DAZAP1/MEF2D and MEF2D/DAZAP1 transcripts. MEF2D is a member of the MEF2 family of DNA binding proteins that activate transcription of genes involved in control of muscle cell differentiation, and signaling pathways that mediate response to mitogenic signals and survival of neurons and T-lymphocytes. DAZAP1 is a novel RNA binding protein expressed most abundantly in the testis. We demonstrate that MEF2D/DAZAP1 binds avidly and specifically to DNA in a manner indistinguishable from that of native MEF2D and is a substantially more potent transcriptional activator than MEF2D. We also show that DAZAP1/MEF2D is a sequence-specific RNA-binding protein. MEF2D has been identified as a candidate oncogene in murine retroviral insertional mutagenesis studies. Our data implicate MEF2D in human cancer and suggest that MEF2D/DAZAP1 and/or DAZAP1/MEF2D contribute to leukemogenesis by altering signaling pathways normally regulated by wild-type MEF2D and DAZAP1.
Leukemia 2005 May
PMID:Cloning and functional characterization of MEF2D/DAZAP1 and DAZAP1/MEF2D fusion proteins created by a variant t(1;19)(q23;p13.3) in acute lymphoblastic leukemia. 1574 50

AF5q31 (also called MCEF) was identified by its involvement in chromosomal translocation with the gene MLL (mixed lineage leukemia), which is associated with infant acute lymphoblastic leukemia. Several potential roles have been proposed for AF5q31 and other family genes, but the specific requirements of AF5q31 during development remain unclear. Here, we show that AF5q31 is essential for spermatogenesis. Although most AF5q31-deficient mice died in utero and neonatally with impaired embryonic development and shrunken alveoli, respectively, 13% of AF5q31-deficient mice thrived as wild-type mice did. However, the male mice were sterile with azoospermia. Histological examinations revealed the arrest of germ cell development at the stage of spermiogenesis, and virtually no spermatozoa were seen in the epididymis. AF5q31 was found to be preferentially expressed in Sertoli cells. Furthermore, mutant mice displayed severely impaired expression of protamine 1, protamine 2, and transition protein 2, which are indispensable to compact the haploid genome within the sperm head, and an increase of apoptotic cells in seminiferous tubules. Thus, AF5q31 seems to function as a transcriptional regulator in testicular somatic cells and is essential for male germ cell differentiation and survival. These results may have clinical implications in the understanding of human male infertility.
 ...
PMID:Infertility with defective spermiogenesis in mice lacking AF5q31, the target of chromosomal translocation in human infant leukemia. 1602 15

Male contraception has focused, to a great extent, on approaches that induce azoospermia or severe oligospermia through accelerated germ cell apoptosis. Understanding the specific steps in the germ cell apoptotic pathways that are affected by male contraceptives will allow more specific targeting in future contraceptive development. In this study, we have used a nonhuman primate model to characterize the key apoptotic pathway(s) in germ cell death after mild testicular hyperthermia, hormonal deprivation, or combined interventions. Groups of 8 adult (7- to 10-year-old) cynomolgus monkeys (Macaca fascicularis) received one of the following treatments: 1) two empty silastic implants; 2) two 5.5-cm testosterone (T) implants; 3) daily exposure of testes to heat (43 degrees C for 30 min) for 2 consecutive days; and 4) two T implants plus testicular heat exposure for two consecutive days. Testicular biopsies were performed before and at Days 3, 8, and 28 of treatment. Treatment with T, heat, or both led to sustained activation of both mitogen-activated protein kinase (MAPK) 1/3 and MAPK14. Activation of MAPK1/3 and MAPK14 were accompanied by an increase in B-cell leukemia/lymphoma (BCL) 2 levels in both cytosolic and mitochondrial fractions of testicular lysates (BAX levels remained unaffected) and cytochrome c and DIABLO release from mitochondria. These treatments also resulted in inactivation of BCL2 through phosphorylation at serine 70, thereby favoring the death pathway. We conclude that the serine phosphorylation of BCL2 and activation of the MAPK14-mediated mitochondria-dependent pathway are critical for male germ cell death in monkeys.
 ...
PMID:Signaling pathways for germ cell death in adult cynomolgus monkeys (Macaca fascicularis) induced by mild testicular hyperthermia and exogenous testosterone treatment. 1737 39

The number of men surviving cancer at a young age has increased dramatically in the past 20 years as a result of early detection and improved cancer treatment protocols; more than 75% of young cancer patients nowadays are long-term survivors. Quality of life has become an important issue in childhood and adult cancer patients. The commonest cancers in patients of reproductive age are leukaemia, Hodgkin's lymphomas and testicular germ cell tumors. Fertility is often impaired after chemotherapy and radiation therapy. Cryopreservation of semen before cancer treatment starts is currently the only method to preserve future male fertility. In some malignancies, especially in germ cell tumors, sperm quality is already abnormal at the time of diagnosis. In approximately 12% of men, no viable spermatozoa are present for cryopreservation before the start of chemotherapy. Cytotoxic therapy influences spermatogenesis at least temporarily and in some cases permanently. The amount of damage inflicted by chemotherapy on spermatogenesis depends on the combination of drugs used and on the cumulative dose given for cancer treatment. Alkylating agents, such as cyclophosphamide and procarbazine, are most detrimental to germ cells. Radiation therapy, especially whole-body irradiation, is also associated with the risk of permanent sterility. Besides the cancer treatment, tumor type and pretreatment fertility are of prognostic value for future fertility in male cancer survivors. After cancer treatment, many men need artificial reproductive techniques to achieve fatherhood; usually in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) is indicated for successful treatment. About 15% of men will use their cryopreserved semen because of persistent azoospermia after cancer treatment. Treatment results with cryopreserved semen are generally good and comparable to general IVF and ICSI results. So far, no studies have reported an increased rate of congenital abnormalities or malignancies in children born from fathers who had cancer treatment is the past, but close follow up is warranted, especially in children born after IVF/ICSI.
 ...
PMID:Male infertility in cancer patients: Review of the literature. 2020


1 2 Next >>