China
Africa
Explore chapters and articles related to this topic
The Scientific Basis of Medicine
Published in John S. Axford, Chris A. O'Callaghan, Medicine for Finals and Beyond, 2023
Chris O'Callaghan, Rachel Allen
At their site of action, drugs interact with molecules termed drug ‘receptors’ or ‘targets’. These are often actual biological receptors, such as hormone receptors, but they may also be any other type of molecule, such as an enzyme or membrane channel. The affinity of a drug-receptor interaction is a measure of how tightly the two molecules bind. An agonist is a substance that has an effect on a specific drug receptor, causing activation of the function of the receptor molecule. A partial agonist has the same type of effect on the function of the receptor molecule, but even at the maximal effect of the drug, the function of the receptor molecule is not activated to its maximal level. An antagonist is a drug that binds, to but opposes, the natural activity of the receptor molecule. Competitive antagonists compete with agonists for the same receptor, but they do not exert an agonist effect themselves and so reduce the effect of any agonist present. In these circumstances, the overall effect will depend on the relative concentrations of agonist and antagonist. A non-competitive antagonist does not compete for the same site but opposes the effect of the agonist by another mechanism. Finally, an irreversible antagonist is an antagonist that inactivates the receptor molecule permanently once it has bound. This effect cannot be reversed, even at high concentration of agonist. Many drug receptors are bound by naturally occurring agonists and antagonists, including hormones and neurotransmitters.
Overview of Traditional Methods of Diagnosis and Treatment for Women-Associated Cancers
Published in Shazia Rashid, Ankur Saxena, Sabia Rashid, Latest Advances in Diagnosis and Treatment of Women-Associated Cancers, 2022
Malika Ranjan, Namyaa Kumar, Safiya Arfi, Shazia Rashid
In the past, most cancers were treated with surgery, radiation, and chemotherapy, however, with the passage of time and advances in diagnosis and treatment modalities, combination of treatments was observed to be more effective. Currently, precision cancer treatment (targeted therapy) and immune-mediated therapies including cancer vaccines, engineered immune cells, and checkpoint inhibitors and gene therapy have been introduced for the treatment of different women-associated cancers [3–5]. Similarly, hormonal therapies are helpful in treating hormone receptors positive cancer such as breast cancer by limiting hormonal growth factors [6]. Also, recent advances in genetic engineering and stem cell research have created the foundation for genetically engineering stem cells with anti-tumour effects as therapeutic vehicles besides dendritic cell-based immunotherapy [4,7].
Oncology
Published in Kaji Sritharan, Jonathan Rohrer, Alexandra C Rankin, Sachi Sivananthan, Essential Notes for Medical and Surgical Finals, 2021
Kaji Sritharan, Jonathan Rohrer, Alexandra C Rankin, Sachi Sivananthan
Growth of some tumours is ‘hormone-dependent’; their cells express hormone receptors which can be targeted in treatment. Important examples include breast cancer – anti-oestrogens (e.g. tamoxifen) and aromatase inhibitors (e.g. exemestane); and prostate cancer – anti-androgens (e.g. zoladex).
Psychometric properties of the French Hot Flash Related Daily Interference Scale (HFRDIS)
Published in Climacteric, 2023
I. Cavadias, R. Rouzier, M. Milder, C. Bonneau, J. Mullaert, D. Hequet
Breast cancer is the most frequently diagnosed cancer in women in the world and the first cause of cancer death in developed countries. The predominant form is characterized by positive hormone receptors (HR+, more than 70% of breast cancers). Hormone therapy thus plays a key role in the strategy of management of these cancers. The two types of hormone therapy used are selective estrogen receptor modulators (exclusive tamoxifen in this indication) and aromatase inhibitors. Like any long-term treatment, hormone therapy requires good patient compliance. Unfortunately, adherence to treatment is often suboptimal. In a large study of a cohort of 8769 patients with localized breast cancer requiring hormone therapy, only 49% of patients took hormone therapy for the recommended duration [4]. Younger women were most at risk of non-compliance. The main reasons for this lack of compliance, especially in young women, might be the significant side effects associated with this type of treatment such as hot flashes, asthenia, anxiety and any other symptoms mimicking menopause. Recently, the side effects of hormone therapy, including hot flashes, were reported in a large French prospective cohort of 4262 patients followed for 5 years, emphasizing the significant impact of these on the daily lives of patients [5].
Efficacy and safety of PARP inhibitors in the treatment of BRCA-mutated breast cancer: an updated systematic review and meta-analysis of randomized controlled trials
Published in Expert Review of Clinical Pharmacology, 2023
Xiaoyu Sun, Suying Xu, Yiming Li, Xuemei Lv, Minjie Wei, Miao He
Additionally, our meta-analysis provides perspectives on the patients who may benefit more from PARPis. In previous meta-analyses, only patients with TNBC achieved statistically significant improvement in PFS based on a subgroup analysis of the hormone receptor status [41]. However, our results suggest that patients with hormone-receptor-positive tumors also benefit in the form of better PFS (HR 0.66 [95%CI, 0.54 to 0.80], p < 0.00001) and ORR (RR 2.99 [95%CI, 1.81 to 4.93], p < 0.0001). According to the guidelines, platinum-based chemotherapy is the preferred option for patients with advanced breast cancer associated with gBRCAm [44]. It is important to note that PFS results were significantly improved compared to PARPis and chemotherapy in patients with or without prior platinum-based therapy, which also differs from what has been reported in previous meta-analyses [41,42].
Hypothesis-driven weight of evidence evaluation indicates styrene lacks endocrine disruption potential
Published in Critical Reviews in Toxicology, 2023
In this WoE methodology, specificity is also addressed by the requirement to evaluate the pattern of the responses relevant to each MoA and to interpret patterns inconsistent with the response expected of known effectors and inhibitors as unlikely to indicate activity via that pathway. Although it is theoretically possible for an agonist or antagonist of a particular hormonal pathway to exhibit a novel pattern of endpoint responses, consistent with the “selective response modifier” concept of hormone receptor interactions, a finite number of response types have been identified for the various hormone receptor systems, each consistent with ligand-receptor affinities, potencies, and the tissue distribution of hormone receptors (see Borgert et al. 2018 and references therein). Assessment approaches that fail to appreciate this basic feature of hormonal action, such as the key characteristic approach proposed by La Merrill et al. (2020), have little utility for identifying potential endocrine disruptors.