Nausea and vomiting are well known side effects related to chemotherapy. Indeed, nausea and vomiting are the most distressing side effects of chemotherapy in cancer patients. Dopamine, serotonin... Show moreNausea and vomiting are well known side effects related to chemotherapy. Indeed, nausea and vomiting are the most distressing side effects of chemotherapy in cancer patients. Dopamine, serotonin and neurokinin1 are thought to be the neurotransmitters that play role in the pathophysiology of Chemotherapy Induced Nausea Vomiting (CINV). Thus, the antagonists of those neurotransmitters are considered as prophylactic antiemetics for CINV. In the 1990s, the use of 5-Hydroxytriptamine receptor antagonists (5-HT3RAs) highly improved the patients__ response rate to antiemetic drugs. In addition, the combination of a neurokinin 1 antagonist, a 5HT3RA and a corticosteroid can further increase the response rate up by 15% in acute phase and 20% in delayed phase. Thus, the international guideline of clinical oncology recommend this combination as prophylactic antiemetic drugs in the acute phase and a combination of dexamethasone __ metoclopramide as prophylactic antiemetics in the delayed phase. However, when the standard antiemetic drug regimens are administered to patients, there are still 20-30% patients in the acute phase and 40% patients in the delayed phase experiencing CINV. Thus, there is a high interindividual variability in response to antiemetic drugs in oncology patients. Some patient characteristics such as female gender, younger patients and history of alcohol drinking could increase the risk of CINV from 20% to 70%. Therefore, individualizing of the use of antiemetics could start by considering the patient characteristics. This thesis focuses on determining the impact of CINV on QoL in Indonesian cancer patients and optimizing the prevention and treatment of CINV by exploration of pharmacogenetic biomarkers. Show less
Perwitasari, D.A.; Straaten, R.J.H.M. van der; Mustofa, M.; Wessels, J.A.M.; Gelderblom, H.; Guchelaar, H.J. 2012
Background: The 5-hydroxytryptamine (5-HT3) receptor is a ligand-operated ion channel with five different receptor subunits (5-HT3A, B, C, D, and E) found in humans. Activation of 5-HT3 receptors... Show moreBackground: The 5-hydroxytryptamine (5-HT3) receptor is a ligand-operated ion channel with five different receptor subunits (5-HT3A, B, C, D, and E) found in humans. Activation of 5-HT3 receptors influences various effects such as drug-induced emesis and causes behavioral problems such as anxiety, depression and cognitive disorders. To explore interethnic differences in the response to 5-HT3 antagonists, we studied haplotype frequencies in the gene encoding the 5-HT3B receptor in Asians and Caucasians.?Methods: Three single nucleotide polymorphisms (SNPs) of the 5-HT3B receptor gene, i.e., deletion AAG at the 5'-UTR position, 18792A>G at the intron position, and 46698G>A at the 3' near gene position, were selected and genotyped in 165 Indonesian cancer patients and 188 Caucasian healthy volunteers. Haplotypes were set with gPlink, whereas the differences in haplotype frequencies between Indonesians and Caucasians were compared using multivariate analysis.?Results: The haplotype profiles based on the deletion AAG, 18792A>G and 46698G>A were AAGAA, AAGAG, AAGGG, and deletion AG in both Indonesians and Caucasians. The frequency of the AAGAG haplotype was 54.8% in Indonesians and 39.9% in Caucasians (p<0.05). The frequency of the AAGGG haplotype was 14.3% in Indonesians and 29.3% in Caucasians. Moreover, there were significant differences in the frequencies of haplotype pairs between Indonesians and Caucasians (p<0.001).?Conclusion: Indonesian cancer patients had significantly different AAGAG and AAGGG haplotype frequencies of the gene encoding the 5-HT3B receptor compared to healthy Caucasians. This finding could be useful for understanding interethnic differences in the response to drugs targeting the 5-HT3B receptor in cancer-treatment-related emesis. Show less
Perwitasari, D.A.; Wessels, J.A.M.; Straaten, R.J.H.M. van der; Baak-Pablo, R.F.; Mustofa, M.; Hakimi, M.; ... ; Guchelaar, H.J. 2011