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International Braz J Urol : Official... 2016Improved targeted therapies for rheumatic diseases were developed recently resulting in a better prognosis for affected patients. Nowadays, patients are living longer... (Review)
Review
BACKGROUND
Improved targeted therapies for rheumatic diseases were developed recently resulting in a better prognosis for affected patients. Nowadays, patients are living longer and with improved quality of life, including fertility potential. These patients are affected by impaired reproductive function and the causes are often multifactorial related to particularities of each disease. This review highlights how rheumatic diseases and their management affect testicular function and male fertility.
MATERIALS AND METHODS
A systematic review of literature of all published data after 1970 was conducted. Data was collected about fertility abnormalities in male patients with systemic lupus erythematosus, rheumatoid arthritis, dermatomyositis, ankylosing spondylitis, Behçet disease and gout. Two independent researchers carried out the search in online databases.
RESULTS
A total of 19 articles were included addressing the following diseases: 7 systemic lupus erythematosus, 6 Behçet disease, 4 ankylosing spondylitis, 2 rheumatoid arthritis, 2 dermatomyositis and one gout. Systemic lupus erythematosus clearly affects gonadal function impairing spermatogenesis mainly due to antisperm antibodies and cyclophosphamide therapy. Behçet disease, gout and ankylosing spondylitis patients, including those under anti-TNF therapy in the latter disease, do not seem to have reduced fertility whereas in dermatomyositis, the fertility potential is hampered by disease activity and by alkylating agents. Data regarding rheumatoid arthritis is scarce, gonadal dysfunction observed as consequence of disease activity and antisperm antibodies.
CONCLUSIONS
Reduced fertility potential is not uncommon. Its frequency and severity vary among the different rheumatic diseases. Permanent infertility is rare and often associated with alkylating agent therapy.
Topics: Alkylating Agents; Behcet Syndrome; Dermatomyositis; Gout; Humans; Infertility, Male; Lupus Erythematosus, Systemic; Male; Rheumatic Diseases; Spondylitis, Ankylosing
PubMed: 27120778
DOI: 10.1590/S1677-5538.IBJU.2014.0595 -
Analytical Chemistry Jan 2018
Review
Topics: Alkylating Agents; Amines; Animals; Chemistry Techniques, Analytical; DNA; DNA Adducts; DNA Damage; Heterocyclic Compounds; Humans; Reactive Oxygen Species
PubMed: 29084424
DOI: 10.1021/acs.analchem.7b04247 -
The Netherlands Journal of Medicine Apr 2011Cyclophosphamide is an alkylating agent used in antineoplastic and immunosuppressive therapies. Symptomatic hyponatraemia is a rare but life-threatening complication in...
Cyclophosphamide is an alkylating agent used in antineoplastic and immunosuppressive therapies. Symptomatic hyponatraemia is a rare but life-threatening complication in patients treated with cyclophosphamide. We report the case of a 64-year-old woman with breast cancer who developed severe symptomatic hyponatraemia with a generalised seizure and convulsions after a second cycle of adjuvant chemotherapy with 5-fluouracil, epirubicin and cyclophosphamide. She completely recovered after correction of the serum sodium concentration without neurological deficits. Physicians prescribing cyclophosphamide, irrespective of the treatment indication and dosage, should be aware of this potentially life-threatening complication.
Topics: Antimetabolites, Antineoplastic; Antineoplastic Agents, Alkylating; Breast Neoplasms; Cyclophosphamide; Epirubicin; Female; Fluorouracil; Humans; Hyponatremia; Middle Aged; Seizures
PubMed: 21527808
DOI: No ID Found -
Health Technology Assessment... Dec 2011Multiple myeloma (MM) is the second most common haematological cancer in the UK. MM is not curable but can be treated with a combination of supportive measures and... (Review)
Review
The clinical effectiveness and cost-effectiveness of bortezomib and thalidomide in combination regimens with an alkylating agent and a corticosteroid for the first-line treatment of multiple myeloma: a systematic review and economic evaluation.
BACKGROUND
Multiple myeloma (MM) is the second most common haematological cancer in the UK. MM is not curable but can be treated with a combination of supportive measures and chemotherapy that aim to extend the duration and quality of survival. The majority of patients are not able to withstand intensive treatment, such as high-dose chemotherapy with autologous stem cell transplantation (SCT), and so they are offered single-agent or combination chemotherapy. Combination therapies typically include chemotherapy with an alkylating agent and a corticosteroid. More recently, combination therapies have incorporated drugs such as thalidomide (Thalidomide Celgene®, Celgene) and bortezomib (Velcade®, Janssen-Cilag).
OBJECTIVE
To assess the clinical effectiveness and cost-effectiveness of bortezomib or thalidomide in combination chemotherapy regimens with an alkylating agent and a corticosteroid for the first-line treatment of MM.
DATA SOURCES
Electronic bibliographic databases, including MEDLINE, EMBASE and The Cochrane Library, were searched from 1999 to 2009 for English-language articles. Bibliographies of articles, grey literature sources and manufacturers' submissions were also searched. Experts in the field were asked to identify additional published and unpublished references.
REVIEW METHODS
Titles and abstracts were screened for eligibility by two reviewers independently. The inclusion criteria specified in the protocol were applied to the full text of retrieved papers by one reviewer and checked independently by a second reviewer. Data extraction and quality assessment were undertaken by one reviewer and checked by a second reviewer. Differences in opinion were resolved through discussion at each stage. A cost-utility decision-analytic model was used to compare the cost-effectiveness estimates of bortezomib in combination with melphalan and prednisolone/prednisone (VMP), thalidomide in combination with cyclophosphamide and attenuated dexamethasone (CTDa), and thalidomide in combination with melphalan and prednisolone/prednisone (MPT) versus melphalan and prednisolone/prednisone (MP).
RESULTS
A total of 1436 records were screened and 40 references were retrieved for the systematic review of clinical effectiveness. Five randomised controlled trials (RCTs) met the inclusion criteria for the review: one RCT evaluated VMP, three evaluated MPT and one evaluated CTDa. The comparator in all of the included trials was MP. The review found that VMP and MPT can both be considered more clinically effective than MP for the first-line treatment of MM in people for whom high-dose therapy and SCT would not be appropriate. CTDa was more effective than MP in terms of complete response but data on survival outcomes did not meet the inclusion criteria. Cost-effectiveness analysis indicated that MPT has a greater probability of being cost-effective than either VMP or CTDa.
LIMITATIONS
For most RCTs, details needed to judge study quality were incompletely reported. All studies stated that the analyses followed intention-to-treat principles but none adequately reported data censoring. Only one RCT contributed data on VMP and the published peer-reviewed follow-up data were immature. For MPT, overall survival data from two trials were eligible for inclusion but the doses of thalidomide differed between the trials and the treatment period was not reflective of current UK practice so the generalisability of the findings was uncertain. Two RCTs had a maintenance phase with thalidomide that did not meet the inclusion criteria so some of these results were not eligible for the review. Limited evidence on health-related quality of life (HRQoL) was provided by the single trial of VMP versus MP.
CONCLUSIONS
Service provision is unlikely to change greatly. As uncertainties remain, further research is needed regarding the use of bortezomib- and thalidomide-containing combination regimens. Head-to-head trials of bortezomib- and thalidomide-containing combination regimes are required, including assessments of patient HRQoL in response to treatment.
FUNDING
The National Institute for Health Research Health Technology Assessment programme.
Topics: Adrenal Cortex Hormones; Alkylating Agents; Antineoplastic Combined Chemotherapy Protocols; Boronic Acids; Bortezomib; Cost-Benefit Analysis; Cyclophosphamide; Humans; Immunosuppressive Agents; Melphalan; Multiple Myeloma; Pyrazines; Quality of Life; Quality-Adjusted Life Years; Randomized Controlled Trials as Topic; Survival Analysis; Thalidomide
PubMed: 22146234
DOI: 10.3310/hta15410 -
International Journal of Molecular... Feb 2023Nitrosamines occur widespread in food, drinking water, cosmetics, as well as tobacco smoke and can arise endogenously. More recently, nitrosamines have been detected as... (Review)
Review
Nitrosamines occur widespread in food, drinking water, cosmetics, as well as tobacco smoke and can arise endogenously. More recently, nitrosamines have been detected as impurities in various drugs. This is of particular concern as nitrosamines are alkylating agents that are genotoxic and carcinogenic. We first summarize the current knowledge on the different sources and chemical nature of alkylating agents with a focus on relevant nitrosamines. Subsequently, we present the major DNA alkylation adducts induced by nitrosamines upon their metabolic activation by CYP450 monooxygenases. We then describe the DNA repair pathways engaged by the various DNA alkylation adducts, which include base excision repair, direct damage reversal by MGMT and ALKBH, as well as nucleotide excision repair. Their roles in the protection against the genotoxic and carcinogenic effects of nitrosamines are highlighted. Finally, we address DNA translesion synthesis as a DNA damage tolerance mechanism relevant to DNA alkylation adducts.
Topics: Nitrosamines; DNA Damage; Alkylation; DNA Repair; Alkylating Agents; DNA Adducts
PubMed: 36902118
DOI: 10.3390/ijms24054684 -
MBio Apr 2022Unique DNA repair enzymes that provide self-resistance against therapeutically important, genotoxic natural products have been discovered in bacterial biosynthetic gene...
Unique DNA repair enzymes that provide self-resistance against therapeutically important, genotoxic natural products have been discovered in bacterial biosynthetic gene clusters (BGCs). Among these, the DNA glycosylase AlkZ is essential for azinomycin B production and belongs to the HTH_42 superfamily of uncharacterized proteins. Despite their widespread existence in antibiotic producers and pathogens, the roles of these proteins in production of other natural products are unknown. Here, we determine the evolutionary relationship and genomic distribution of all HTH_42 proteins from and use a resistance-based genome mining approach to identify homologs associated with known and uncharacterized BGCs. We find that AlkZ-like (AZL) proteins constitute one distinct HTH_42 subfamily and are highly enriched in BGCs and variable in sequence, suggesting each has evolved to protect against a specific secondary metabolite. As a validation of the approach, we show that the AZL protein, HedH4, associated with biosynthesis of the alkylating agent hedamycin, excises hedamycin-DNA adducts with exquisite specificity and provides resistance to the natural product in cells. We also identify a second, phylogenetically and functionally distinct subfamily whose proteins are never associated with BGCs, are highly conserved with respect to sequence and genomic neighborhood, and repair DNA lesions not associated with a particular natural product. This work delineates two related families of DNA repair enzymes-one specific for complex alkyl-DNA lesions and involved in self-resistance to antimicrobials and the other likely involved in protection against an array of genotoxins-and provides a framework for targeted discovery of new genotoxic compounds with therapeutic potential. Bacteria are rich sources of secondary metabolites that include DNA-damaging genotoxins with antitumor/antibiotic properties. Although produce a diverse number of therapeutic genotoxins, efforts toward targeted discovery of biosynthetic gene clusters (BGCs) producing DNA-damaging agents is lacking. Moreover, work on toxin-resistance genes has lagged behind our understanding of those involved in natural product synthesis. Here, we identified over 70 uncharacterized BGCs producing potentially novel genotoxins through resistance-based genome mining using the azinomycin B-resistance DNA glycosylase AlkZ. We validate our analysis by characterizing the enzymatic activity and cellular resistance of one AlkZ ortholog in the BGC of hedamycin, a potent DNA alkylating agent. Moreover, we uncover a second, phylogenetically distinct family of proteins related to Escherichia coli YcaQ, a DNA glycosylase capable of unhooking interstrand DNA cross-links, which differs from the AlkZ-like family in sequence, genomic location, proximity to BGCs, and substrate specificity. This work defines two families of DNA glycosylase for specialized repair of complex genotoxic natural products and generalized repair of a broad range of alkyl-DNA adducts and provides a framework for targeted discovery of new compounds with therapeutic potential.
Topics: Alkylating Agents; Anti-Bacterial Agents; Biological Products; DNA; DNA Adducts; DNA Glycosylases; Mutagens; Streptomyces
PubMed: 35311535
DOI: 10.1128/mbio.03297-21 -
Nature Reviews. Cancer Jan 2012Alkylating agents constitute a major class of frontline chemotherapeutic drugs that inflict cytotoxic DNA damage as their main mode of action, in addition to collateral... (Review)
Review
Alkylating agents constitute a major class of frontline chemotherapeutic drugs that inflict cytotoxic DNA damage as their main mode of action, in addition to collateral mutagenic damage. Numerous cellular pathways, including direct DNA damage reversal, base excision repair (BER) and mismatch repair (MMR), respond to alkylation damage to defend against alkylation-induced cell death or mutation. However, maintaining a proper balance of activity both within and between these pathways is crucial for a favourable response of an organism to alkylating agents. Furthermore, the response of an individual to alkylating agents can vary considerably from tissue to tissue and from person to person, pointing to genetic and epigenetic mechanisms that modulate alkylating agent toxicity.
Topics: Alkylating Agents; Base Pair Mismatch; DNA Damage; DNA Repair; Humans
PubMed: 22237395
DOI: 10.1038/nrc3185 -
Clinics (Sao Paulo, Brazil) 2012Temozolomide is an alkylating agent used in the treatment of gliomas and, more recently, aggressive pituitary adenomas and carcinomas. Temozolomide methylates DNA and,... (Review)
Review
Temozolomide is an alkylating agent used in the treatment of gliomas and, more recently, aggressive pituitary adenomas and carcinomas. Temozolomide methylates DNA and, thereby, has antitumor effects. O6-methylguanine-DNA methyltransferase, a DNA repair enzyme, removes the alkylating adducts that are induced by temozolomide, thereby counteracting its effects. A Medline search for all of the available publications regarding the use of temozolomide for the treatment of pituitary tumors was performed. To date, 46 cases of adenohypophysial tumors that were treated with temozolomide, including 30 adenomas and 16 carcinomas, have been reported. Eighteen of the 30 (60%) adenomas and 11 of the 16 (69%) carcinomas responded favorably to treatment. One patient with multiple endocrine neoplasia type 1 and an aggressive prolactin-producing adenoma was also treated and demonstrated a good response. No significant complications have been attributed to temozolomide therapy. Thus, temozolomide is an effective treatment for the majority of aggressive adenomas and carcinomas. Evidence indicates that there is an inverse correlation between levels of O6-methylguanine-DNA methyltransferase immunoexpression and therapeutic response. Alternatively, high-level O6-methylguanine-DNA methyltransferase immunoexpression correlates with an unfavorable response. Here, we review the use of temozolomide for treating pituitary neoplasms.
Topics: Adenoma; Antineoplastic Agents, Alkylating; Carcinoma; Dacarbazine; Humans; Pituitary Neoplasms; Temozolomide
PubMed: 22584716
DOI: 10.6061/clinics/2012(sup01)20 -
Cellular and Molecular Life Sciences :... Nov 2010O (6)-methylguanine-DNA methyltransferase (MGMT) repairs the cancer chemotherapy-relevant DNA adducts, O (6)-methylguanine and O (6)-chloroethylguanine, induced by... (Review)
Review
O (6)-methylguanine-DNA methyltransferase (MGMT) repairs the cancer chemotherapy-relevant DNA adducts, O (6)-methylguanine and O (6)-chloroethylguanine, induced by methylating and chloroethylating anticancer drugs, respectively. These adducts are cytotoxic, and given the overwhelming evidence that MGMT is a key factor in resistance, strategies for inactivating MGMT have been pursued. A number of drugs have been shown to inactivate MGMT in cells, human tumour models and cancer patients, and O (6)-benzylguanine and O (6)-[4-bromothenyl]guanine have been used in clinical trials. While these agents show no side effects per se, they also inactivate MGMT in normal tissues and hence exacerbate the toxic side effects of the alkylating drugs, requiring dose reduction. This might explain why, in any of the reported trials, the outcome has not been improved by their inclusion. It is, however, anticipated that, with the availability of tumour targeting strategies and hematopoetic stem cell protection, MGMT inactivators hold promise for enhancing the effectiveness of alkylating agent chemotherapy.
Topics: Animals; Antineoplastic Agents, Alkylating; Clinical Trials as Topic; Enzyme Inhibitors; Humans; Neoplasms; O(6)-Methylguanine-DNA Methyltransferase
PubMed: 20717836
DOI: 10.1007/s00018-010-0491-7 -
Medical Oncology (Northwood, London,... May 2014Recently, bendamustine has become an important agent in the treatment for patients with lymphoid malignancies. Although the drug has received approval for second-line... (Review)
Review
Recently, bendamustine has become an important agent in the treatment for patients with lymphoid malignancies. Although the drug has received approval for second-line therapy in indolent lymphoma, a growing body of evidence suggests its efficacy and safety in first-line use. The results of randomised and observational studies with bendamustine as front-line therapy in non-Hodgkin lymphoma (NHL) with emphasis on efficacy and toxicity are presented. Furthermore, completed and ongoing clinical trials evaluating upfront bendamustine effectiveness in combination with other agents are discussed. The review refers mainly to indolent lymphoma, mantle cell lymphoma and aggressive lymphoma, as the most commonly diagnosed NHL types. Finally, we elaborated on the safety profile of bendamustine and the perspectives of using the drug as a first-line therapy.
Topics: Antineoplastic Agents, Alkylating; Bendamustine Hydrochloride; Humans; Lymphoma, Non-Hodgkin; Nitrogen Mustard Compounds; Prognosis
PubMed: 24752517
DOI: 10.1007/s12032-014-0944-1