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PXR, CAR and HNF4alpha genotypes and their association with pharmacokinetics and pharmacodynamics of docetaxel and doxorubicin in Asian patients

Hor SY, Lee SC, Wong CI, Lim YW, Lim RC, Wang LZ, et al.

Pharmacogenomics J, 2008 Apr;8(2):139-46.
PMID: 17876342

Previously studied candidate genes have failed to account for inter-individual variability of docetaxel and doxorubicin disposition and effects. We genotyped the transcriptional regulators of CYP3A and ABCB1 in 101 breast cancer patients from 3 Asian ethnic groups, that is, Chinese, Malays and Indians, in correlation with the pharmacokinetics and pharmacodynamics of docetaxel and doxorubicin. While there was no ethnic difference in docetaxel and doxorubicin pharmacokinetics, ethnic difference in docetaxel- (ANOVA, P=0.001) and doxorubicin-induced (ANOVA, P=0.003) leukocyte suppression was observed, with Chinese and Indians experiencing greater degree of docetaxel-induced myelosuppression than Malays (Bonferroni, P=0.002, P=0.042), and Chinese experiencing greater degree of doxorubicin-induced myelosuppression than Malays and Indians (post hoc Bonferroni, P=0.024 and 0.025). Genotyping revealed both PXR and CAR to be well conserved; only a PXR 5'-untranslated region polymorphism (-24381A>C) and a silent CAR variant (Pro180Pro) were found at allele frequencies of 26 and 53%, respectively. Two non-synonymous variants were identified in HNF4alpha (Met49Val and Thr130Ile) at allele frequencies of 55 and 1%, respectively, with the Met49Val variant associated with slower neutrophil recovery in docetaxel-treated patients (ANOVA, P=0.046). Interactions were observed between HNF4alpha Met49Val and CAR Pro180Pro, with patients who were wild type for both variants experiencing least docetaxel-induced neutropenia (ANOVA, P=0.030). No other significant genotypic associations with pharmacokinetics or pharmacodynamics of either drug were found. The PXR-24381A>C variants were significantly more common in Indians compared to Chinese or Malays (32/18/21%, P=0.035) Inter-individual and inter-ethnic variations of docetaxel and doxorubicin pharmacokinetics or pharmacodynamics exist, but genotypic variability of the transcriptional regulators PAR, CAR and HNF4alpha cannot account for this variability.

Matched MeSH terms: Doxorubicin/administration & dosage
Fulltext Modified methods of nanoparticles synthesis in pH-sensitive nano-carriers production for doxorubicin delivery on MCF-7 breast cancer cell line

Hamidu A, Mokrish A, Mansor R, Razak ISA, Danmaigoro A, Jaji AZ, et al.

Int J Nanomedicine, 2019;14:3615-3627.
PMID: 31190815 DOI: 10.2147/IJN.S190830

Purpose: Modified top-down procedure was successfully employed in the synthesis of aragonite nanoparticles (NPs) from cheaply available natural seawater cockle shells. This was with the aim of developing a pH-sensitive nano-carrier for effective delivery of doxorubicin (DOX) on MCF-7 breast cancer cell line. Methods: The shells were cleaned with banana pelts, ground using a mortar and pestle, and stirred vigorously on a rotary pulverizing blending machine in dodecyl dimethyl betane solution. This simple procedure avoids the use of stringent temperatures and unsafe chemicals associated with NP production. The synthesized NPs were loaded with DOX to form DOX-NPs. The free and DOX-loaded NPs were characterized for physicochemical properties using field emission scanning electron microscopy, transmission electron microscopy, zeta potential analysis, Fourier transform infrared spectroscopy, and X-ray diffraction. The release profile, cytotoxicity, and cell uptake were evaluated. Results: NPs had an average diameter of 35.50 nm, 19.3% loading content, 97% encapsulation efficiency, and a surface potential and intensity of 19.1±3.9 mV and 100%, respectively. A slow and sustained pH-specific controlled discharge profile of DOX from DOX-NPs was observed, clearly showing apoptosis/necrosis induced by DOX-NPs through endocytosis. The DOX-NPs had IC50 values 1.829, 0.902, and 1.0377 µg/mL at 24, 48, and 72 hrs, while those of DOX alone were 0.475, 0.2483, and 0.0723 µg/mL, respectively. However, even at higher concentration, no apparent toxicity was observed with the NPs, revealing their compatibility with MCF-7 cells with a viability of 92%. Conclusions: The modified method of NPs synthesis suggests the tremendous potential of the NPs as pH-sensitive nano-carriers in cancer management because of their pH targeting ability toward cancerous cells.

Matched MeSH terms: Doxorubicin/administration & dosage*
Fulltext Synergistic inhibition of melanoma xenografts by Brequinar sodium and Doxorubicin

Dorasamy MS, Ab A, Nellore K, Wong PF

Biomed Pharmacother, 2019 Feb;110:29-36.
PMID: 30458345 DOI: 10.1016/j.biopha.2018.11.010

Malignant melanoma continues to be a fatal disease for which novel and long-term curative breakthroughs are desired. One such innovative idea would be to assess combination therapeutic treatments - by way of combining two potentially effective and very different therapy. Previously, we have shown that DHODH inhibitors, A771726 and Brequinar sodium (BQR) induced cell growth impairment in melanoma cells. Similar results were seen with DHODH RNA interference (shRNA). In the present study, we showed that combination of BQR with doxorubicin resulted in synergistic and additive cell growth inhibition in these cells. In addition, in vivo studies with this combination of drugs demonstrated an almost 90% tumor regression in nude mice bearing melanoma tumors. Cell cycle regulatory proteins, cyclin B1 and its binding partner pcdc-2 and p21 were significantly downregulated and upregulated respectively following the combined treatment. Given that we have observed synergistic effects with BQR and doxorubicin, both in vitro and in vivo, these drugs potentially represent a new combination in the targeted therapy of melanoma.

Matched MeSH terms: Doxorubicin/administration & dosage*
Treatment options for locally advanced breast cancer--experience in an Asian tertiary hospital

Chong HY, Taib NA, Rampal S, Saad M, Bustam AZ, Yip CH

Asian Pac J Cancer Prev, 2010;11(4):913-7.
PMID: 21133600

BACKGROUND: Locally advanced breast cancer (LABC) is characterized by the presence of a large primary tumour (>5 cm) associated with or without skin or chest-wall involvement (T4) or with fixed (matted) axillary lymph nodes in the absence of any evidence of distant metastases. These cancers are classified as stage IIIA and IIIB according to the AJCC Staging System. Treatment of choice involves combinations of surgery, chemotherapy, radiotherapy and/or hormonal therapy. Current guidelines recommend primary surgery or neoadjuvant therapy followed by surgery. The primary objective of this study was to compare the outcome of LABC patients subjected to neoadjuvant chemotherapy before surgery and those who underwent surgery as the primary treatment and to determine prognostic predictors. Secondary objectives were to evaluate the response after neoadjuvant therapy and to determine the treatment compliance rate.
METHODS: This retrospective study of Stage III breast cancer patients was conducted over a 5 year period from 1998 to 2002. The survival data were obtained from the National Registry of Births and Deaths with the end-point of the study in April 2006. The Kaplan Meier method was applied for survival analysis. Cox regression analysis by stepwise selection was performed to identify important prognostic factors.
RESULTS: Out of a 155 evaluable patients, 74 (47.7%) had primary surgery, 62 (40%) had neoadjuvant chemotherapy, 10 patients (6.5%) were given Tamoxifen as the primary treatment, while 9 patients (5.8%) defaulted any form of treatment. After neoadjuvant chemotherapy, 9 patients defaulted further treatment, leaving 53 evaluable patients. Out of these 53 evaluable patients, 5 patients (9.4%) had complete pathological response, 5 (9.4%) a complete clinical response, and 26 (49.1%) had partial response after neoadjuvant chemotherapy. The 5-year survival in the primary surgery group was 56.7 % compared to 44.7% in the neoadjuvant chemotherapy group (p<0.01). The important prognostic factors were race, size of tumour, nodal status, estrogen receptor status and response to neoadjuvant chemotherapy.
CONCLUSION: Patients who had primary surgery had better survival than those who underwent neoadjuvant chemotherapy, which may be due to bias in the selection of patients for neoadjuvant chemotherapy. Out of a total of 155 patients, 25.1% defaulted part of the treatment, or did not receive optimal treatment, emphasizing the importance of psychosocial support and counselling for this group of patients.

Matched MeSH terms: Doxorubicin/administration & dosage
Hemodynamic effects of HPMA copolymer based doxorubicin conjugate: A randomized controlled and comparative spectral study in conscious rats

Cheah HY, Šarenac O, Arroyo JJ, Vasić M, Lozić M, Glumac S, et al.

Nanotoxicology, 2017 03;11(2):210-222.
PMID: 28098511 DOI: 10.1080/17435390.2017.1285071

Conjugation of Doxorubicin (DOX) to N-(2-hydroxypropyl) methylacrylamide copolymer (HPMA) has significantly reduced the DOX-associated cardiotoxicity. However, the reports on the impact of HPMA-DOX conjugates on the cardiovascular system such as blood pressure (BP) and heart rate (HR) were in restrained animals using tail cuff and/or other methods that lacked the resolution and sensitivity. Herein, we employed radiotelemetric-spectral-echocardiography approach to further understand the in vivo cardiovascular hemodynamics and variability post administration of free DOX and HPMA-DOX. Rats implanted with radio-telemetry device were administered intravenously with DOX (5 mg/kg), HPMA-DOX (5 mg DOX equivalent/kg) and HPMA copolymer and subjected to continuous cardiovascular monitoring and echocardiography for 140 days. We found that DOX-treated rats had ruffled fur, reduced body weight (BW) and a low survival rate. Although BP and HR were normal, spectral analysis indicated that their BP and HR variabilities were reduced. All rats exhibited typical signs of cardiotoxicity at histopathology. In contrast, HPMA-DOX rats gained weight over time and survived. Although BP, HR and related variabilities were unaffected, the left ventricular end diastolic volume (EDV) of these rats, as well as of the HPMA copolymer-treated rats, was found increased at the end of observation period. Additionally, HPMA copolymer caused microscopic injury of the heart tissue. All of these suggest the necessity of caution when employing HPMA as carrier for prolonged drug delivery. The current study also indicates the potential of radiotelemetric-spectral-echocardiography approach for improved preclinical cardiovascular risk assessment of polymer-drug conjugate and other nano-sized-drug constructs.

Matched MeSH terms: Doxorubicin/administration & dosage
Outcome of treatment in adult acute lymphoblastic leukaemia in an Asian population: comparison with previous multicentre German study

Bosco I, Teh A

Leukemia, 1995 Jun;9(6):951-4.
PMID: 7596183

Reports on the outcome of treatment in ALL in Asian (non-Caucasian) adults have been few, and published results compare very unfavourably with results of treatment from 'Western' centres. Seventy-four newly diagnosed Malaysian patients with ALL between the ages of 15 and 69 were treated from 1986 to 1990. The clinical features and prognostic factors were similar to those reported in 'Western' series. The chemotherapy protocol utilized was adapted from the one used by Hoelzer et al in the multicentre German study. The complete remission rate was 73%. The probability of continuous complete remission at 5 years was 29% with a median duration of remission of 15 months. This compares with Hoelzer's initial results of 77% CR rate and 35% CCR at 5 years. Patients with an initial white cell count of less than 30 x 10(9)/l at presentation were found to have a significantly better disease-free survival than those with a count of more than 30 x 10(9)/l (35 vs 22%, P = 0.026, univariate analysis). There was no difference in leukaemia-free survival according to age, sex, ethnic group, or immunophenotype. These results show that the use of moderately intensive chemotherapy protocols in Asian (non-Caucasian) patients achieves similar results to those used in Caucasians. We also showed that the difficulties in 'curing' approximately 70% of adult patient with ALL are universal.

Matched MeSH terms: Doxorubicin/administration & dosage
Fulltext pH-responsive Virus-like Nanoparticles with Enhanced Tumour-targeting Ligands for Cancer Drug Delivery

Biabanikhankahdani R, Alitheen NBM, Ho KL, Tan WS

Sci Rep, 2016 11 24;6:37891.
PMID: 27883070 DOI: 10.1038/srep37891

Multifunctional nanocarriers harbouring specific targeting moieties and with pH-responsive properties offer great potential for targeted cancer therapy. Several synthetic drug carriers have been studied extensively as drug delivery systems but not much information is available on the application of virus-like nanoparticles (VLNPs) as multifunctional nanocarriers. Here, we describe the development of pH-responsive VLNPs, based on truncated hepatitis B virus core antigen (tHBcAg), displaying folic acid (FA) for controlled drug delivery. FA was conjugated to a pentadecapeptide containing nanoglue bound on tHBcAg nanoparticles to increase the specificity and efficacy of the drug delivery system. The tHBcAg nanoparticles loaded with doxorubicin (DOX) and polyacrylic acid (PAA) demonstrated a sustained drug release profile in vitro under tumour tissue conditions in a controlled manner and improved the uptake of DOX in colorectal cancer cells, leading to enhanced antitumour effects. This study demonstrated that DOX-PAA can be packaged into VLNPs without any modification of the DOX molecules, preserving the pharmacological activity of the loaded DOX. The nanoglue can easily be used to display a tumour-targeting molecule on the exterior surface of VLNPs and can bypass the laborious and time-consuming genetic engineering approaches.

Matched MeSH terms: Doxorubicin/administration & dosage*
Targeted polymeric nanoparticle for anthracycline delivery in hypoxia-induced drug resistance in metastatic breast cancer cells

Almoustafa HA, Alshawsh MA, Chik Z

Anticancer Drugs, 2021 Aug 01;32(7):745-754.
PMID: 33675612 DOI: 10.1097/CAD.0000000000001065

Poly lactic-co-glycolic acid (PLGA) nanoparticles are intensively studied nanocarriers in drug delivery because of their biodegradability and biochemical characteristics. Polyethylene glycol (PEG) coating for nanocarriers gives them long circulation time in blood and makes them invisible to the reticuloendothelial system. Breast cancer cells have greater uptake of hyaluronic acid compared to normal cells as it binds to their overexpressed CD44 receptors. Since hypoxia plays an important role in cancer metastasis; we formulated PEG-PLGA nanoparticles coated with hyaluronic acid as targeted delivery system for doxorubicin (DOX) using nanoprecipitation method, and characterized them for chemical composition, size, surface charge, shape, and encapsulation efficiency. Then we tested them in vitro on hypoxia-optimized metastatic breast cancer cells. The nanoparticles were spherical with an average size of about 106 ± 53 nm, a negative surface charge (-15 ± 3 mV), and high encapsulation efficiency (73.3 ± 4.1%). In vitro investigation with hypoxia-elevated CD44 MDA-MB-231 cells showed that hyaluronic acid-targeted nanoparticles maintained their efficacy despite hypoxia-induced drug resistance unlike free DOX and nontargeted nanoparticles. In conclusion, this study revealed a simple third generation nanoparticle formulation for targeted treatment of hypoxia-induced drug resistance in breast cancer metastatic cells. Further, optimization is needed including In vivo efficacy and nanoparticle-specific pharmacokinetic studies.

Matched MeSH terms: Doxorubicin/administration & dosage
Fulltext Primary non-Hodgkin's lymphoma presenting as a uterine cervical mass

Ab Hamid S, Wastie ML

Singapore Med J, 2008 Mar;49(3):e73-5.
PMID: 18362991

We report a 43-year-old woman who presented with post-coital bleeding. Pelvic examination revealed a uterine cervical mass, which confirmed to be large B cell lymphoma on histopathological examination. Computed tomography showed a primary lesion in the uterine cervix with no lymph node or other extranodal involvement. The patient responded to CHOP (cyclophosphamide, adriamycin, vincristine and prednisolone) chemotherapy regime with no major side effects.

Matched MeSH terms: Doxorubicin/administration & dosage