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2.
J Oncol ; 2022: 2183055, 2022.
Article in English | MEDLINE | ID: mdl-36059801

ABSTRACT

Background: Lung cancer is the leading cause of cancer death in Aotearoa New Zealand, killing over 1,700 people each year. Despite the burden of lung cancer in Aotearoa New Zealand, the popular press has referred to it as the cancer type that no one talks about. Here, we investigate one factor that may contribute to this state of affairs: lung cancer stigma. Methods: Participants were university students and members of the general public. University students were recruited via an online experiment participation system in 2021. Members of the public were recruited via social media. All participants completed the Cancer Stigma Scale (CSS) for one of five cancer types (lung, cervical, breast, skin, or bowel). The CSS is a 25-item scale with six subscales: awkwardness, avoidance, severity, policy opposition, personal responsibility, and financial discrimination. Results: The mean age of participants was 24.3 (Standard Deviation = 10.4). Data from each subscale were submitted to an analysis of covariance (ANCOVA), with cancer type as a between-participant factor (5: lung, cervical, breast, skin, or bowel) and stigma as the dependent variable. Relative to most other cancer types, people were more likely to avoid someone with lung cancer, view interacting with someone with lung cancer as more awkward, and view people with lung cancer as being responsible for their condition. Conclusion: The Health Research Council of New Zealand recently funded the very first trial of lung cancer screening in Aotearoa New Zealand. The current study suggests that addressing stigma will be essential for the success of such programs, with stigma likely influencing those who engage in such trials.

3.
Curr Cancer Drug Targets ; 22(2): 97-107, 2022.
Article in English | MEDLINE | ID: mdl-34994310

ABSTRACT

Mathematical modelling of tumour mutation dynamics has suggested that cancer drug targets that have different resistance mechanisms should be good candidates for combination treatment. This is because the development of mutations that cause resistance to all drugs at once should arise relatively infrequently. However, it is difficult to identify drug targets fulfilling this requirement for particular cancers. Here we present four experimental criteria that we argue are necessary (but not sufficient) conditions that drug combinations should meet in order to be considered for combination drug treatment aimed at delaying or overcoming cancer drug resistance. We present the results of our own experiments - guided by these criteria - using anaplastic lymphoma kinase mutated lung cancer cells. Each set of experiments demonstrate results for different drug combinations. We conclude that the combination of ALK and MEK inhibitors come closest to meeting all our criteria.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Drug Combinations , Drug Resistance, Neoplasm , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mutation , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
4.
Pharmacol Res ; 175: 105986, 2022 01.
Article in English | MEDLINE | ID: mdl-34800627

ABSTRACT

During cardiac reperfusion after myocardial infarction, the heart is subjected to cascading cycles of ischaemia reperfusion injury (IRI). Patients presenting with this injury succumb to myocardial dysfunction resulting in myocardial cell death, which contributes to morbidity and mortality. New targeted therapies are required if the myocardium is to be protected from this injury and improve patient outcomes. Extensive research into the role of mitochondria during ischaemia and reperfusion has unveiled one of the most important sites contributing towards this injury; specifically, the opening of the mitochondrial permeability transition pore. The opening of this pore occurs during reperfusion and results in mitochondria swelling and dysfunction, promoting apoptotic cell death. Activation of mitochondrial ATP-sensitive potassium channels (mitoKATP) channels, uncoupling proteins, and inhibition of glycogen synthase kinase-3ß (GSK3ß) phosphorylation have been identified to delay mitochondrial permeability transition pore opening and reduce reactive oxygen species formation, thereby decreasing infarct size. Statins have recently been identified to provide a direct cardioprotective effect on these specific mitochondrial components, all of which reduce the severity of myocardial IRI, promoting the ability of statins to be a considerate preconditioning agent. This review will outline what has currently been shown in regard to statins cardioprotective effects on mitochondria during myocardial IRI.


Subject(s)
Cardiotonic Agents/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Myocardial Reperfusion Injury/drug therapy , Animals , Cardiotonic Agents/pharmacology , Glycogen Synthase Kinase 3 beta/antagonists & inhibitors , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Mitochondria, Heart/drug effects , Mitochondria, Heart/physiology , Mitochondrial Permeability Transition Pore/metabolism , Mitophagy/drug effects , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/physiopathology , Potassium Channels/physiology
5.
J Histochem Cytochem ; 69(10): 627-631, 2021 10.
Article in English | MEDLINE | ID: mdl-34617806

ABSTRACT

Histochemistry of tumor sections is a widely employed technique utilized to examine cell death in preclinical xenograft animal models of cancer. However, this is under the assumption that tumors are homogeneous, leading to practices such as automatic cell counting across the entire section. We have noted that in our experiments the core of the tumor is largely or partially necrotic, and lacks evidence of vascularization (in contrast to the outer areas of the tumor). We note that this can bias and confound immunohistochemical analyses that do not take care to sample areas of interest in a way to take this into account. Design-based stereology with image analysis techniques is an alternative process that could be used to measure the volume of the necrotic region compared to the volume of the whole tumor.


Subject(s)
Image Processing, Computer-Assisted , Neovascularization, Pathologic/pathology , Animals , Apoptosis , Immunohistochemistry , Male , Mice , Mice, Nude , Neoplasms, Experimental/pathology
6.
ChemMedChem ; 16(8): 1308-1315, 2021 04 20.
Article in English | MEDLINE | ID: mdl-33320428

ABSTRACT

A second-generation enantiospecific synthesis of spiroleucettadine is described. The original reported antibacterial activity was not observed when the experiment was repeated on the synthetic samples; however, significant anti-proliferative activity was uncovered for both enantiomers of spiroleucettadine. Comparison of the optical rotational data and ORD-CD spectra of both enantiomers and the reported spectrum from the natural source have not provided a definitive answer regarding the absolute stereochemistry of naturally occurring spiroleucettadine. Efforts then focussed on alteration at the C-4 and C-5 positions of the slightly more active (-)-spiroleucettadine. Ten analogues were synthesised, with three analogues found to possess similar anti-proliferative profiles to spiroleucettadine against the H522 lung cancer cell line.


Subject(s)
Antineoplastic Agents/pharmacology , Imidazoles/pharmacology , Spiro Compounds/pharmacology , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Humans , Imidazoles/chemical synthesis , Spiro Compounds/chemical synthesis , Stereoisomerism
7.
Pharmacology ; 105(11-12): 715-718, 2020.
Article in English | MEDLINE | ID: mdl-32460299

ABSTRACT

Crizotinib is a tyrosine kinase inhibitor used to treat anaplastic lymphoma kinase-positive lung cancer. There is in vitro evidence that crizotinib may auto-inhibit cytochrome P450 3A (CYP3A) activity, with important implications for crizotinib pharmacokinetics. In order to test whether crizotinib treatment alters CYP3A activity in vivo, mice were treated with 5 and 25 mg/kg crizotinib (p.o.) daily for 14 days. Results showed that crizotinib treatment did not alter CYP3A activity as determined by erythromycin N-demethylation. In addition, CYP3A polypeptide expression as measured by Western blot was unchanged. Therefore, our results do not support CYP3A inhibition by crizotinib in vivo.


Subject(s)
Crizotinib/pharmacology , Cytochrome P-450 CYP3A/metabolism , Protein Kinase Inhibitors/pharmacology , Animals , Male , Mice , Mice, Inbred BALB C , Microsomes, Liver/enzymology , Microsomes, Liver/metabolism
8.
Med Hypotheses ; 134: 109434, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31634772

ABSTRACT

Dexamethasone has been observed to cause night-time wakefulness without accompanying fatigue. It is proposed here that the drug interrupts a sleep signal, and that although sleep has an ultimate ecological function, this signal is a proximate mechanism but not an ultimate physiological necessity, such that sleep is not a necessity.


Subject(s)
Models, Neurological , Sleep/physiology , Adaptation, Physiological , Cytokines/physiology , Dexamethasone/pharmacology , Fatigue/drug therapy , Fatigue/physiopathology , Humans , Sleep/drug effects , Sleep Deprivation/physiopathology , Wakefulness/physiology , Wakefulness-Promoting Agents/pharmacology , Wakefulness-Promoting Agents/therapeutic use , gamma-Aminobutyric Acid/physiology
9.
Eur J Pharmacol ; 865: 172749, 2019 Dec 15.
Article in English | MEDLINE | ID: mdl-31654622

ABSTRACT

Non-small cell lung cancer with ALK rearrangements can be targeted effectively with ALK inhibitors such as crizotinib. However, cancer progression typically occurs within a year as drug resistance develops. One strategy to overcome this drug resistance is to determine if novel cytotoxic agents retain the ability to kill lung cancer cells that have developed ALK inhibitor resistance. We therefore examined curcumin, a drug with anticancer properties, and 2 s-generation curcumin derivatives (1-methyl-3,5-bis[(E)-4-pyridyl) methylidene]-4-piperidone (RL66) and 1-isopropyl-3,5-bis[(pyridine-3-yl) methylene]piperidin-4-one (RL118)) in lung cancer cell lines. The cytotoxicity of curcumin, RL66, and RL118 were tested in both ALK+ lung cancer cells (H3122), crizotinib resistant ALK+ cells (CR-H3122) and ALK- lung cancer cells (A549), both alone and in combination with crizotinib. ALK+ cells were 2-3x more sensitive to RL66 and RL118 than ALK- cells, with the drugs' eliciting IC50 values in the range of 0.7-1 µM in H3122 cells. Retained cytotoxic potency of the curcumin derivatives in crizotinib resistant cells indicated that mechanisms of resistance to the two drug types are independent, with resistance to ALK inhibitors not necessarily causing cross-resistance to curcumin derivatives. This was further corroborated by drug combination analysis where the effect of the drugs in combination was consistent with Bliss additivity, consistent with independent targets for crizotinib and curcumin derivatives. Results from Western blotting showed that RL118 (2 µM) inhibited p-ALK/ALK by ~50%, which was not as potent as the 90% inhibition elicited by crizotinib (0.25 µM). Since this is the primary mechanism of crizotinib cytotoxicity this provides further evidence of independent mechanisms of toxicity.


Subject(s)
Anaplastic Lymphoma Kinase/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Carcinoma, Non-Small-Cell Lung/drug therapy , Crizotinib/pharmacology , Curcumin/analogs & derivatives , Curcumin/pharmacology , Lung Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Anaplastic Lymphoma Kinase/metabolism , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Drug Resistance, Neoplasm , Drug Synergism , Humans , Lung Neoplasms/metabolism
10.
F1000Res ; 8: 190, 2019.
Article in English | MEDLINE | ID: mdl-31448098

ABSTRACT

Lung cancer drug development requires screening in animal models. We aimed to develop orthotopic models of human non-small lung cancer using A549 and H3122 cells delivered by tail vein injection. This procedure has been used previously for a mouse lung cancer (Lewis lung carcinoma) and as a model of human breast cancer metastasis to lung. We report that the procedure led to poor animal condition 7-8 weeks after injection, and produced lesions in the lungs visible at necropsy but we were unable identify individual cancer cells using immunohistochemistry. We conclude that if this method is to produce a model that can be used in drug experiments, improvements are required for cancer cell detection post mortem, such as by using of a fluorescently tagged human lung cancer cell line.


Subject(s)
Carcinoma, Lewis Lung , Lung Neoplasms , Neoplasm Transplantation , A549 Cells , Animals , Disease Models, Animal , Humans , Mice
11.
N Z Med J ; 132(1494): 49-56, 2019 05 03.
Article in English | MEDLINE | ID: mdl-31048824

ABSTRACT

As New Zealand considers cannabis legal reform, we ask: what exactly is medicinal cannabis, and why does this matter? Cannabis is not a single entity but comes in diverse forms with various active ingredients. This contrasts with the legal and pharmaceutical definitions of medicines, with wide-ranging implications for quality control, prescriber practice and the assessment of clinical evidence. We argue that what is considered a medicine in the legal and pharmaceutical sense should not be changed in an ad hoc way to accommodate cannabis, but that cannabis products should be held to the same standards as other medicines.


Subject(s)
Marijuana Use/legislation & jurisprudence , Medical Marijuana , Humans , New Zealand
12.
Curr Drug Res Rev ; 11(1): 33-39, 2019.
Article in English | MEDLINE | ID: mdl-30829178

ABSTRACT

BACKGROUND: The degree to which cannabis use causes long term harm to mental functioning is contentious. OBJECTIVE: To determine the evidence for residual and long term effects of cannabis use on mental functions. METHOD: Comprehensively review human studies addressing detrimental effects on human mental and life functioning. RESULTS: Heavy use causes immediate effects on perception, mood and sedation, but also deficits in cognitive ability. But cessation following heavy use has withdrawal effects and is associated with residual effects on cognition that may last for several weeks. Heavy use also raises the risk of impoverishment of life outcomes and a decline in socioeconomic status as well as the risk of mental health problems. Young age at the start of heavy cannabis use causes a risk of lifelong detrimental effects, and as a worst case together with genetic vulnerability exacerbate a predisposition to schizophrenia. CONCLUSION: Heavy regular use of cannabis that begins in adolescence heightens the risk of longterm impairment of life and mental functioning.


Subject(s)
Brain/drug effects , Cognition/drug effects , Marijuana Abuse/complications , Marijuana Use/adverse effects , Mental Disorders/etiology , Humans , Marijuana Abuse/psychology , Marijuana Use/psychology , Mental Disorders/psychology , Social Class
14.
J Cardiovasc Pharmacol ; 72(4): 191-194, 2018 10.
Article in English | MEDLINE | ID: mdl-30080756

ABSTRACT

Cannabinoid CB2 receptor agonists are under investigation for clinical use. At the same time, synthetic cannabinoids have been implicated in a number of deaths. One cause of death is thought to be cardiac arrest subsequent to extreme tachycardia. Central mechanisms are thought to play a role in this, with CB1 but not CB2 receptors thought to mediate central effects. However, the direct effects of cannabinoids on the heart are less well understood. We therefore tested the effects of cannabinoids on isolated rat atria to test whether activation of myocardial CB1 and CB2 receptors could contribute to tachycardia. Although we found a moderate effect that can be attributed to CB1 receptors, we did not find any evidence for chronotropic effects by a CB2 receptor activation. Our results indicate that cannabinoid cardiotoxicity may partially involve CB1 receptors in the myocardium, and that CB2 receptor agonists are unlikely to have significant effects on the heart.


Subject(s)
Arachidonic Acids/pharmacology , Atrial Function/drug effects , Benzoxazines/pharmacology , Cannabinoid Receptor Agonists/pharmacology , Cannabinoids/pharmacology , Heart Atria/drug effects , Morpholines/pharmacology , Naphthalenes/pharmacology , Receptor, Cannabinoid, CB1/agonists , Receptor, Cannabinoid, CB2/agonists , Animals , Arachidonic Acids/toxicity , Benzoxazines/toxicity , Cannabinoid Receptor Agonists/toxicity , Cannabinoids/toxicity , Cardiotoxicity , Heart Atria/metabolism , Heart Atria/physiopathology , Heart Rate/drug effects , In Vitro Techniques , Macrophage Activation/drug effects , Male , Mice , Morpholines/toxicity , Myocardial Contraction/drug effects , Naphthalenes/toxicity , RAW 264.7 Cells , Rats, Wistar , Receptor, Cannabinoid, CB1/metabolism , Receptor, Cannabinoid, CB2/metabolism , Signal Transduction/drug effects , Tachycardia/chemically induced , Tachycardia/metabolism , Tachycardia/physiopathology
15.
Med Hypotheses ; 113: 27-29, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29523288

ABSTRACT

The claim has been made that it can be proven that most published findings in medical, biological, and allied sciences are false and that the reason for this can be proven and explained with a mathematical model. It has not, however, been mathematically proven that most research findings are false, and this can be proven. The model used in the proof is incoherent and has been falsified. Furthermore, advice to researchers derived from the model is misleading and distracts from more important issues in experimental standards.


Subject(s)
Biomedical Research/methods , Research Design , Biomedical Research/trends , Models, Theoretical , Reproducibility of Results
16.
Curr Drug Targets ; 19(11): 1344-1349, 2018.
Article in English | MEDLINE | ID: mdl-28641517

ABSTRACT

Although ß2-receceptor agonists are powerful bronchodilators and are at the forefront of asthma symptom relief, patients who use them frequently develop partial resistance to them. This can be a particularly serious problem during severe attacks, where high dose ß2-agonist treatment is the front line therapy. Alternative bronchodilators are urgently needed. In this article we review the evidence for the bronchodilator effects of the cannabinoid CB1 receptor tetrahydrocannabinol (THC) and suggest that the mechanisms of action for these effects are sufficiently independent of the mechanisms of standard bronchodilators to warrant clinical investigation. Specifically, clinical trials testing the bronchodilator effects of THC in ß2 agonist resistant asthmatic patients would show whether THC could fill the role of rescue bronchodilator in cases of ß2 agonist resistance.


Subject(s)
Asthma/drug therapy , Bronchodilator Agents/pharmacology , Dronabinol/pharmacology , Drug Resistance/drug effects , Adrenergic beta-2 Receptor Agonists/therapeutic use , Asthma/metabolism , Bronchodilator Agents/therapeutic use , Clinical Trials as Topic , Dronabinol/therapeutic use , Humans , Molecular Targeted Therapy , Receptor, Cannabinoid, CB1/metabolism
17.
Anticancer Agents Med Chem ; 18(3): 367-374, 2018.
Article in English | MEDLINE | ID: mdl-29110626

ABSTRACT

There is now a considerable body of evidence for sildenafil possessing anticancer properties. In this article, we argue the case for testing sildenafil as a lung cancer therapy chemoadjuvant. Currently, lung cancer is a disease with insufficient treatment options, with only 20% of patients responding to systemic chemotherapy, and even incremental potential improvements should be explored. We review the literature concerning the biochemical, physiological and metabolic effects on cancer cells by sildenafil alone, and when combined with chemotherapeutic agents. Most studies have shown that sildenafil is cytotoxic to cancer cells, both as a monotherapy and as a chemoadjuvant. Sildenafil enhances cancer cell apoptosis when used as a chemoadjuvant both in vitro and in vivo. In particular, in rodent experiments sildenafil has decreased tumour size compared to chemotherapy alone. Sildenafil has also been proven as an agent to decrease drug-efflux by cancer cells and increases blood perfusion to lung tissue, which can potentially increase the dosage of chemotherapeutic agents delivered to lung cancer cells compared to healthy tissue. In addition, the proven clinical effects of sildenafil on other lung diseases suggest that it could improve other patient outcomes, such as right ventricular function and quality of life. Sildenafil may also extend the half-life of docetaxel and some small molecule inhibitors used in lung cancer treatment by acting as an inhibitor of CYP3A4. We conclude that the evidence strongly warrants clinical investigation into the use of sildenafil as an agent for the treatment of lung-cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Drug Repositioning , Lung Neoplasms/drug therapy , Phosphodiesterase 5 Inhibitors/pharmacology , Sildenafil Citrate/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Cytochrome P-450 CYP3A/metabolism , Humans , Lung Neoplasms/pathology
18.
Sci Rep ; 7(1): 13955, 2017 10 24.
Article in English | MEDLINE | ID: mdl-29066738

ABSTRACT

ALK positive non-small cell lung cancer is highly responsive to ALK inhibitors such as crizotinib, but drug resistance typically develops within a year of treatment. In this study we investigated whether IGF-1R is an independent druggable target in ALK-positive lung cancer cells. We confirmed that combination ALK and IGF-1R inhibitor treatment is synergistically cytotoxic to ALK-positive lung cancer cells and that this remains the case for at least 12 days after initial exposure to crizotinib. ALK-positive cells with acquired resistance to crizotinib did not acquire cross-resistance to IGF-1R inhibition, though combination treatment in the resistant cells gave additive rather than synergistic cytotoxicity. We concluded that IGF-1R is an independent druggable target in ALK-positive lung cancer and support the trial of combination treatment.


Subject(s)
Anaplastic Lymphoma Kinase/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Crizotinib/pharmacology , Drug Resistance, Neoplasm/drug effects , Lung Neoplasms/pathology , Molecular Targeted Therapy , Receptor, IGF Type 1/metabolism , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Clinical Trials as Topic , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism
19.
Neurosci Lett ; 614: 39-42, 2016 Feb 12.
Article in English | MEDLINE | ID: mdl-26762784

ABSTRACT

Cannabinoids produce analgesia through a variety of mechanisms. It has been proposed that one mechanism is by modulating the release of CGRP in the spinal cord pain pathways. Previous studies have reported that cannabinoids, particularly CB2 receptor agonists, can modulate CGRP release in the isolated rat spinal cord. In our experiments, the TRPV1 agonist capsaicin evoked CGRP release and this was supressed by the TRPV1 antagonist capsazepine and by the opioid receptor agonist DAMGO. However, none of the cannabinoid receptor agonists that we tested were able to modulate evoked CGRP release; including WIN 55,212-2, methanandamide, and GW405833. These results question the role of spinal cord cannabinoid receptors in the regulation of CGRP signaling.


Subject(s)
Calcitonin Gene-Related Peptide/metabolism , Cannabinoids/pharmacology , Spinal Cord/drug effects , Animals , Arachidonic Acids/pharmacology , Benzoxazines/pharmacology , Cannabinoid Receptor Agonists/pharmacology , Capsaicin/analogs & derivatives , Capsaicin/pharmacology , Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology , In Vitro Techniques , Indoles/pharmacology , Lumbosacral Region , Male , Morpholines/pharmacology , Naphthalenes/pharmacology , Rats, Wistar , Receptors, Opioid/agonists , Sciatic Nerve/drug effects , Sciatic Nerve/metabolism , Spinal Cord/metabolism , TRPV Cation Channels/agonists , TRPV Cation Channels/antagonists & inhibitors
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