Phase I and pharmacological study of the broad-spectrum tyrosine kinase inhibitor JNJ-26483327 in patients with advanced solid tumours

Background:

JNJ-26483327 is an oral, potent, multi-targeted tyrosine kinase inhibitor, inhibiting kinases of epidermal growth factor receptor (EGFR)-1, -2 and -4, rearranged during transfection (RET) receptor, vascular endothelial growth factor receptor (VEGFR)-3 and Src family (Lyn, Fyn, Yes) at low nanomolar concentrations. This phase I, accelerated titration study assessed maximum tolerated dose, safety, pharmacokinetics and pharmacodynamic effects of JNJ-26483327.

Methods:

Nineteen patients with advanced cancers received JNJ-26483327 continuous twice daily (BID) in escalating dose cohorts ranging from 100 to 2100 mg. Pharmacodynamic effects were assessed in paired skin biopsies and blood.

Results:

JNJ-26483327 was well tolerated in doses up to 1500 mg BID, with target-inhibition-related toxicity such as diarrhoea and skin rash, and other common reported toxicities being nausea, vomiting, anorexia and fatigue. At 2100 mg, two episodes of dose-limiting toxicity were observed, consisting of grade 3 anorexia and a combination of grade 3 anorexia and fatigue, respectively. Pharmacokinetics were dose proportional up to 1500 mg in which plasma levels were obtained showing anti-tumour activity in xenograft mouse models. Pharmacodynamic analysis did not show a substantial effect on expression of Ki-67, p27^kip1, phosphorylated mitogen-activated protein kinase, phosphorylated Akt and EGFR, and serum levels of sVEGFR-2, VEGF-C and VEGF-D remained unchanged. Stable disease was noted in six patients (32%).

Conclusion:

JNJ-26483327 is well tolerated and shows a predictable pharmacokinetic profile; the recommended dose for further studies is 1500 mg BID.     

Dietary acrylamide intake and estrogen and progesterone receptor-defined postmenopausal breast cancer risk

Acrylamide, a potential human carcinogen, has been discovered in a variety of heat-treated carbohydrate-rich food products. Previously, dietary acrylamide intake was shown to be associated with endocrine-related cancers in humans. We assessed the association between dietary acrylamide intake and risk of postmenopausal breast cancer stratified by estrogen and progesterone receptor status. This study was embedded within the Netherlands Cohort Study on diet and cancer, which was initiated in 1986 enrolling 62,573 women aged 55–69 years at baseline. After 13.3 years of follow-up, 2225 incident breast cancer cases were ascertained, with hormone receptor status information for 43%. Cox proportional hazards analysis was applied to determine hazard ratios in quintiles of dietary acrylamide intake stratifying on estrogen receptor (ER) and progesterone receptor (PR) and smoking status. No association was observed for overall breast cancer or receptor-negative breast cancer risk, irrespective of smoking status. A statistically non-significantly increased risk of ER positive, PR positive and joint receptor-positive breast cancer was found in never-smoking women. The multivariable-adjusted hazard ratios were 1.31 (95% CI: 0.87–1.97, P _trend = 0.26) for ER+, 1.47 (0.86–2.51, P _trend = 0.14) for PR+, and 1.43 (0.83–2.46, P _trend = 0.16) for ER+PR+, when comparing women in the highest quintile of acrylamide intake (median 36.8 μg/day) to women in the lowest (median 9.5 μg/day). This study showed some indications of a positive association between dietary acrylamide intake and receptor-positive breast cancer risk in postmenopausal never-smoking women. Further studies are needed to confirm or refute our observations.     

Age- and gender-specific risk of death after first hospitalization for heart failure

Background  

Hospitalization for heart failure (HF) is associated with high-in-hospital and short- and long-term post discharge mortality. Age and gender are important predictors of mortality in hospitalized HF patients. However, studies assessing short- and long-term risk of death stratified by age and gender are scarce.     

Radiation induced cell loss in rat submandibular gland and its relation to gland function

Purpose : To understand early and late radiation-induced loss of function of the submandibular gland, changes in cell number were documented and correlated with data on gland function. Modulation of the radiation effect by sialogogues was used to investigate possible mechanisms of action. Materials and methods : Rats were irradiated with a single dose of 15 Gy of X-rays after pre-treatment with either saline, the muscarinic receptor agonists methacholine or pilocarpine, the adrenergic receptor agonist phenylephrine or methacholine plus phenylephrine. Before and 1-240 days after irradiation, submandibular saliva flow rate was measured. At the same time points and from comparable animals submandibular glands were carefully extirpated, weighed and prepared for light microscopic examination. Results : Soon after irradiation (<30 days) no significant loss of cells was observed, whereas the gland function was severely compromized. Sialogogue pre-treatment attenuated the radiation-induced loss of gland function. At later intervals a considerable loss of acinar cells and to a lesser extent loss of granular convoluted tubule cells were observed. Gland function subsequently declined slowly. Pre-treatment with sialogogues gave transient protection against cell loss and loss of gland function. Conclusions : The lack of cell loss observed soon after irradiation indicates that the observed reduction in gland function was caused by a compromised functioning of the acini. The later loss of cells is probably due to death of cells that normally proliferate, leading to a further reduced secretory capacity. Protection of gland morphology and function by sialogogues at later times must therefore involve resistance of progenitor cells to radiation-induced cell death.     

Membrane Radiosensitivity of Fatty Acid Supplemented Fibroblasts as Assayed by the Loss of Intracellular Potassium

Summary

Leakage of potassium from mouse fibroblast LM cells, X-irradiated at 0°C with doses up to 400 Gy is shown to be related to plasma membrane lipid composition. Fatty acid supplemented cells, containing about 40 per cent polyunsaturated fatty acids (PUFA) in their membranes were much more sensitive to radiation, as measured by increased permeability, than normal cells, which contained 7 per cent PUFA. The damage observed after irradiation at 0°C was partially repaired during a post-irradiation incubation at 22°C. The o.e.r. for potassium leakage was about 4 for normal fibroblasts and 8 for the PUFA-supplemented cells. No oxygen-dependent radiation damage could be observed in cells treated with high amounts of vitamin E. Depletion of glutathione in PUFA cells sensitized oxic cells to radiation damage, resulting in an increase of the o.e.r. from 8 to 17. No lipid peroxidation (malondialdehyde production and disappearance of fatty acyl chains) could be demonstrated. While PUFA, normal and vitamin E grown cells showed a differential sensitivity in radiation-induced potassium leakage and trypan blue uptake (high doses, interphase death), no difference in radiation-induced clonogenic ability (reproductive death) could be observed after the different cell treatments. The experiments reported are supportive of a role of membranes in the mechanism of radiation-induced interphase death and show that increased damage may be expected when high amounts of polyunsaturated membrane lipids are present under conditions of low amounts of appropriate antioxidants.     

Effect of Hyperthermia on DNA Loop-size in HeLa S3 Cells

Summary

Nuclear matrices of heated and non-heated HeLa S3 cells were isolated and average DNA loop-sizes were compared. Heat treatment (30 min at 45°C) resulted in an ultimate survival level of the cells of about 10 per cent. The loop-size determinations were done on nuclear material isolated from the cells directly after heat treatment. In the nuclear matrices isolated from the heated cells about 1·8 times more protein was bound as compared to the matrices from control cells. Enzymatic analysis using DNase I digestion, followed by centrifugation on neutral sucrose gradients, was performed. Also, halo visualization was combined with autoradiography. Both methods revealed no gross alterations in DNA loop-sizes. The possible function of DNA loop organization in the effect of hyperthermic interference with DNA-related processes is discussed.     

Contrasting Dose-rate Effects of γ-irradiation on Rat Salivary Gland Function

The aim of this study was to investigate the effects of ⁶⁰Co irradiation delivered at high (HDR) and low (LDR) dose-rates on rat salivary gland function. Total-body irradiation (TBI; total doses 7·5, 10 and 12·5 Gy) was applied from a ⁶⁰Co source at dose-rates of 1 cGy/min (LDR) and 40 cGy/min (HDR) followed by syngeneic bone marrow rescue. Four days before and 1–30 days after TBI, submandibular and parotid saliva samples were collected in male albino Wistar rats using Lashley cups. Lag phase and flow rate were recorded, and [Na⁺] and [K⁺] were measured. The severity of salivary gland dysfunction for each dose-rate was dependent on total TBI dose in all parameters. LDR irradiation significantly enhanced the increase of lag phase, while it tended to further decrease flow rate during days 0–3. At later times the reverse effect was seen with significant LDR sparing in most cases. The changes in [Na⁺] and [K⁺] showed similar trends; LDR had an enhancing effect for early damage, while beyond day 3 it consistently produced less damage. From this dose-rate study it is concluded that the early postirradiation changes in salivary gland function are probably predominantly caused by irradiation damage to membrane structures and are less the result of reproductive failure. The later changes in salivary gland function are probably mainly dependent on repopulation of surviving stem cells.     

Familial aggregation of malignant mesothelioma in former workers and residents of Wittenoom,Western Australia

Clustering of cases of malignant mesothelioma within families has often been observed, but disentangling genetic and exposure effects has not been done. Former workers and residents exposed to crocidolite at Wittenoom, Western Australia, where many families shared exposure to asbestos, have had high rates of mesothelioma. Our study aimed to estimate the additional risk of mesothelioma in relatives, after allowance for common exposure to crocidolite. More than 11,000 former asbestos workers and residents from Wittenoom have been followed up in cancer and death registries. Levels of exposure for all members of the Wittenoom cohorts have been estimated previously. Relationships between family members of all mesothelioma cases were established from questionnaires, birth and death certificates. Expected numbers of cases of mesothelioma were estimated by fitting a Weibull survival model to all data, based on time from first asbestos exposure, duration and intensity of exposure and age. For each family group, the earliest case was considered the index case. Predicted risk was estimated for each subject from the time of diagnosis of the index case. Familial risk ratios were estimated by dividing observed cases by the sum of risks of all same degree relatives of index cases. There were 369 family groups with at least one case of mesothelioma and a further 25 cases of mesothelioma among relatives in the same families, with 12.9 expected. The risk ratio for blood relatives was 1.9 (95% confidence interval [CI] = 1.3–2.9, p = 0.002). These findings suggest an important, but not large, genetic component in mesothelioma, similar to many other cancers.     

Acute irradiation effects on morphology and function of rat submandibular glands

In this study the morphologic and functional changes were compared after irradiation (single dose, 15 Gy) of rat submandibular salivary glands. Before and 1-10 days after local irradiation of the gland region, samples of submandibular saliva were collected after stimulation by pilocarpine. At the same time-points and also 3 h postirradiation submandibular glands were carefully extirpated and prepared for histocytologic examination (LM, TEM). Maximal increase of the lag phase and decrease of the flow rate were observed 3 days after irradiation, while [K+] and [Na+] increased and decreased, respectively, from days 1 and 3 after irradiation. Morphologic changes were observed from the third hour after irradiation, were maximal 3 days after irradiation and had partially recovered by day 10. Three hours and 1 day after irradiation degranulation of convoluted granulated tubes (CGT) was observed. Three days after irradiation the most striking morphologic changes in serous and mucous cells were distension of the cisternae of the RER, degeneration of mitochondria and vacuolization of the cytoplasm. Fibril-like condensations of electron dense material in the mucous granules were observed 3 h, 1 and 6 days after irradiation. Regranulation of CGT cells was observed from day 6. From this study it is concluded that changes in salivary gland function can be observed before major morphologic changes occur. Functional changes persist after the morphologic changes seem to have virtually returned to normal.     

ANTIBODIES TO SACCHAROMYCES CEREVISIAE and ANTINEUTROPHIL CYTOPLASMIC AUTOANTIBODIES IN INFLAMMATORY BOWEL DISEASE: ASSESSMENT and RELEVANCE IN AN AUSTRALIAN POPULATION USING TWO DIFFERENT ASCA ASSAY KITS

A number of North American and European studies have elucidated a relationship between antibodies to the yeast Saccharomyces cerevisiae (ASCA) and Crohn's disease (CD).
Aims  (1) To ascertain whether this relationship is relevant to Australian patients; (2) To compare the results with two different commercial ASCA kits; (3) To examine the usefulness of this test in combination with perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) for distinguishing Crohn's disease from ulcerative colitis (UC).
Methods  Serum samples were obtained from 28 patients with CD, 27 patients with UC and 22 non-IBD patients presenting for investigation of other gastroenterological illnesses. ASCA IgG and IgA were determined by enzyme immunoassay using the two test kits. pANCA was detected by indirect immunofluorescence.
Results  Using the Medizym test kit, the presence of either IgG or IgA ASCA was 50% sensitive and 93% specific for CD. The QUANTA Lite kit yielded a higher sensitivity of 79% but specificity of 74%. The sensitivity of pANCA for UC was 48% but was 100% specific. Used in combination, ASCA+ve/pANCA–ve was only 50% sensitive but 100% specific for CD using the Medizym kit compared with 79% sensitivity and 93% specificity using QUANTA Lite. The combination of ASCA–ve/pANCA+ve was 41% sensitive and 100% specific for ulcerative colitis using the Medizym kit compared with 30% sensitive and 100% specific using QUANTA Lite.
Conclusions  At least 50% of Australian patients with CD have ASCA detectable in serum, confirming the results of overseas studies. Sensitivity was greater with the QUANTA Lite kit whereas the Medizym kit was slightly more specific. ASCA may aid in the diagnosis of CD. When used in combination with pANCA it may also help distinguish CD from UC in difficult cases.