A Multiplexed Approach to Assess Small Cell Lung Cancer Subtype Heterogeneity in Primary and Patient-Derived Tumor Samples

Unlocking the heterogeneity of cancers is crucial for developing therapeutic approaches that effectively eradicate disease. As our understanding of markers specific to cancer subclones or subtypes expands, there is a growing demand for advanced technologies that enable the simultaneous investigation of multiple targets within an individual tumor sample. Indeed, multiplex approaches offer distinct benefits, particularly when tumor specimens are small and scarce. Here we describe the utility of two fluorescence-based multiplex approaches; fluorescent Western blots, and multiplex immunohistochemistry (Opal™) staining to interrogate heterogeneity, using small cell lung cancer as an example. Critically, the coupling of Opal™ staining with advanced image quantitation, permits the dissection of cancer cell phenotypes at a single cell level. These approaches can be applied to patient biopsies and/or patient-derived xenograft (PDX) models and serve as powerful methodologies for assessing tumor cell heterogeneity in response to therapy or between metastatic lesions across diverse tissue sites.

Trabid patient mutations impede the axonal trafficking of adenomatous polyposis coli to disrupt neurite growth

ZRANB1 (human Trabid) missense mutations have been identified in children diagnosed with a range of congenital disorders including reduced brain size, but how Trabid regulates neurodevelopment is not understood. We have characterized these patient mutations in cells and mice to identify a key role for Trabid in the regulation of neurite growth. One of the patient mutations flanked the catalytic cysteine of Trabid and its deubiquitylating (DUB) activity was abrogated. The second variant retained DUB activity, but failed to bind STRIPAK, a large multiprotein assembly implicated in cytoskeleton organization and neural development. Zranb1 knock-in mice harboring either of these patient mutations exhibited reduced neuronal and glial cell densities in the brain and a motor deficit consistent with fewer dopaminergic neurons and projections. Mechanistically, both DUB-impaired and STRIPAK-binding-deficient Trabid variants impeded the trafficking of adenomatous polyposis coli (APC) to microtubule plus-ends. Consequently, the formation of neuronal growth cones and the trajectory of neurite outgrowth from mutant midbrain progenitors were severely compromised. We propose that STRIPAK recruits Trabid to deubiquitylate APC, and that in cells with mutant Trabid, APC becomes hyperubiquitylated and mislocalized causing impaired organization of the cytoskeleton that underlie the neuronal and developmental phenotypes.

Treatment of severe acute respiratory syndrome with lopinavir/ritonavir: a multicentre retrospective matched cohort study

OBJECTIVES

To investigate the possible benefits and adverse effects of the addition of lopinavir/ritonavir to a standard treatment protocol for the treatment of severe acute respiratory syndrome.

DESIGN

Retrospective matched cohort study.

SETTING

Four acute regional hospitals in Hong Kong.

PATIENTS AND METHODS

Seventy-five patients with severe acute respiratory syndrome treated with lopinavir/ritonavir in addition to a standard treatment protocol adopted by the Hospital Authority were matched with controls retrieved from the Hospital Authority severe acute respiratory syndrome central database. Matching was done with respect to age, sex, the presence of co-morbidities, lactate dehydrogenase level and the use of pulse steroid therapy. The 75 patients treated with lopinavir/ritonavir were divided into two subgroups for analysis: lopinavir/ritonavir as initial treatment, and lopinavir/ritonavir as rescue therapy. These groups were compared with matched cohorts of 634 and 343 patients, respectively. Outcomes including overall death rate, oxygen desaturation, intubation rate, and use of pulse methylprednisolone were reviewed.

RESULTS

The addition of lopinavir/ritonavir as initial treatment was associated with a reduction in the overall death rate (2.3%) and intubation rate (0%), when compared with a matched cohort who received standard treatment (15.6% and 11.0% respectively, P<0.05) and a lower rate of use of methylprednisolone at a lower mean dose. The subgroup who had received lopinavir/ritonavir as rescue therapy, showed no difference in overall death rate and rates of oxygen desaturation and intubation compared with the matched cohort, and received a higher mean dose of methylprednisolone.

CONCLUSION

The addition of lopinavir/ritonavir to a standard treatment protocol as an initial treatment for severe acute respiratory syndrome appeared to be associated with improved clinical outcome. A randomised double-blind placebo-controlled trial is recommended during future epidemics to further evaluate this treatment.

Intensive insulin therapy with insulin lispro: a randomized trial of continuous subcutaneous insulin infusion versus multiple daily insulin injection

OBJECTIVE

To evaluate glycemic control, hypoglycemic events, and quality of life in patients treated with continuous subcutaneous insulin infusion (CSII) and multiple daily insulin injection (MDI), with insulin lispro as the principal insulin.

RESEARCH DESIGN AND METHODS

This clinical trial enrolled 27 patients with type 1 diabetes. They were randomly assigned to CSII (n = 13) or MDI (n = 14) treatment regimens. Glycemic control (HbA(1c) level) was the primary outcome and was measured monthly for 9 months. Secondary outcomes were patient reports of hypoglycemic events (recorded monthly for 9 months) and quality of life assessed at 9 months using the Diabetes Quality of Life (DQOL) questionnaire.

RESULTS

A significant decrease in HbA(1c) from baseline was shown for both groups. However, the overall treatment effect (CSII - MDI) for HbA(1c) was +0.08% (95% CI -0.23 to +0.39, P > 0.10). This was significantly less than the a priori limit of +/-0.5% (P = 0.004). The relative treatment effect ([CSII - MDI]/MDI) for the overall number of hypoglycemic events was +9% (95% CI -37 to +87, P > 0.10). There were no statistically significant differences between treatment groups for any of the DQOL subscales.

CONCLUSIONS

No statistically significant differences in glycemic control, reported hypoglycemic events, or quality of life were found in this study. Furthermore, a clinically significant difference of more than +/-0.5% HbA(1c) between the two regimens can be confidently ruled out. We conclude that the choice of intensive insulin therapy should be a matter of patient preference, consistent with lifestyle.

Effect of intensive therapy on early macrovascular disease in young individuals with type 1 diabetes. A systematic review and meta-analysis

OBJECTIVE

We conducted a systematic review of randomized controlled trials (RCTs) of intensive insulin therapy (IIT) in type 1 diabetes to determine the effect on macrovascular complications.

RESEARCH DESIGN AND METHODS

MEDLINE (1966-1996), Citation Index, reference lists, and personal files were used to identify RCTs of > 2 years' duration comparing IIT to conventional therapy (CT) in type 1 diabetes. Two independent reviewers applied selection criteria and identified 11 studies; 5 were subsequently excluded because no data were available for macrovascular complications. Data were extracted on macrovascular disease and cardiovascular risk factors. Macrovascular disease was defined as angina, myocardial infarction, angioplasty, coronary artery bypass graft, stroke, claudication, or peripheral bypass. The first event of each type was counted.

RESULTS

IIT decreased the number of macrovascular events (odds ratio [OR] 0.55, [95% CI 0.35-0.88], P = 0.015) but had no significant effect on the number of patients developing macrovascular disease (OR 0.72, [95% CI 0.44-1.17], P = 0.22) or on macrovascular mortality (OR 0.91, [95% CI 0.31-2.65], P = 0.93).

CONCLUSIONS

IIT decreases the extent of early macrovascular disease in young individuals with type 1 diabetes but has no effect on the number of patients affected or on macrovascular mortality. These data suggest that IIT may stabilize macrovascular disease or prevent progression in those at risk.

Glucose production, utilization, and cycling in response to moderate exercise in obese subjects with type 2 diabetes and mild hyperglycemia

The glucoregulatory and hormonal responses to moderate-intensity exercise (50% VO2max for 45 min) were examined in subjects with type 2 diabetes and mild hyperglycemia. We studied seven obese subjects with type 2 diabetes and seven lean and seven obese control subjects (fasting plasma glucose levels, 7.5 +/- 0.5, 4.8 +/- 0.1, and 5.2 +/- 0.1 mmol/l, respectively). Glucose production, utilization, and cycling (flux between glucose and glucose-6-phosphate [G-6-P]) were measured with [6-(3)H]glucose and [2-(3)H]glucose using the constant specific-activity method. Insulin levels decreased normally during exercise in diabetic subjects. Plasma glucose levels decreased in diabetic subjects, but remained constant in control subjects. Basal glucose production was not different among groups and increased similarly during exercise. The decrease in plasma glucose in diabetic subjects was due to greater glucose utilization (867 +/- 83 vs. 726 +/- 143 micromol x m(-2) x min(-1); P < 0.05). This was a consequence of the mass effect of hyperglycemia, since glucose metabolic clearance increased similarly in all groups. Glucose cycling, expressed as a percentage of total glucose output (i.e., flux through G-6-P) was elevated at rest (P < 0.01), but decreased during exercise (P < 0.01). The catecholamine response to exercise was blunted in diabetic subjects, presumably indicating autonomic dysfunction. In conclusion, during moderate-intensity exercise in obese diabetic subjects with mild hyperglycemia, 1) insulin secretory responses were normally regulated; 2) glucose homeostasis was different from that in nondiabetic subjects because glucose levels decreased during exercise; 3) the decrease in plasma glucose was due to greater-than-normal rates of glucose utilization, which were sustained by hyperglycemia; and 4) elevated basal rates of glucose cycling decreased during exercise, presumably because exercise simultaneously lowered plasma glucose, was associated with a blunted catecholamine response, and accentuated an underlying defect in hepatic glucokinase activity in type 2 diabetes.

Insulin lispro in CSII: results of a double-blind crossover study

Insulin lispro is a human insulin analog that dissociates more rapidly than human regular insulin after subcutaneous injection, resulting in higher insulin levels at an earlier point in time and a shorter duration of action. The aim of the study was to evaluate if this pharmacokinetic difference would translate into better postprandial and overall control in 30 IDDM patients (age, 35.1 +/- 1.5 years; male-female ratio, 17:13; BMI, 24.8 +/- 0.5 kg/m2; HbA1c, 8.03 +/- 0.13% at baseline) treated with continuous subcutaneous insulin infusion (CSII; Disetronic H-TRON V100) in a double-blind crossover clinical study. Patients were randomized to insulin lispro or human regular insulin for 3 months before crossing over to the other insulin for another 3 months. All meal boluses were given immediately before breakfast, lunch, and supper. An eight-point blood glucose profile was measured once weekly, and HbA1c levels were measured monthly. At the end of the 3-month treatment period, HbA1c levels were significantly lower with insulin lispro, compared with human regular insulin: 7.66 +/- 0.13 vs. 8.00 +/- 0.16% (P = 0.0041). While preprandial, bedtime, and 2:00 A.M. values for blood glucose were not significantly different, 1-h postprandial blood glucose was significantly improved after breakfast, lunch, and dinner with insulin lispro, compared with human regular insulin: 8.35 vs. 9.79 mmol/l (P = 0.006), 7.58 vs. 8.74 mmol/l (P = 0.049), and 7.85 vs. 9.01 mmol/l (P = 0.03). The incidence of hypoglycemia per 30 days (blood glucose levels, <3.0 mmol/l) was 8.4 +/- 1.3 before randomization, decreasing to 6.0 +/- 0.9 for insulin lispro and to 7.6 +/- 1.3 for regular insulin during the last month of the study. Two patients in each group reported insulin precipitation. We conclude that insulin lispro improves glycemic control in CSII without increasing the risk of hypoglycemia.

Disseminated skeletal tuberculosis with skull involvement

We report a patient with widespread osteolytic lesions, including extensive involvement of the skull, due to Mycobacterium tuberculosis. Response to treatment with antituberculosis drugs was slow with appearance of new lesions while on therapy despite a sensitive organism. Excision of diseased skull bone was eventually done, after which no new lesions appeared in the ensuing 14 months.

Release of tumor necrosis factor alpha by human peritoneal macrophages in response to toxic shock syndrome toxin-1

We examined the release in vitro of tumor necrosis factor-alpha (TNF-alpha) by peritoneal macrophages and peripheral blood monocytes following incubation with toxic shock syndrome toxin-1 (TSST-1). We obtained peritoneal macrophages from 22 women at laparoscopy and peripheral blood monocytes from four healthy women during both the midfollicular and midluteal phases of the menstrual cycle. The samples were incubated for 24 hours at 37 C with 10(-2)-10(4) ng/mL of TSST-1 or 10(4) ng/mL of bacterial endotoxin. Tumor necrosis factor-alpha activity was determined with a bioassay using an actinomycin D-sensitized WEHI-164 murine fibrosarcoma cell line. Twenty-four-hour incubation with TSST-1 resulted in a dose-dependent release of TNF-alpha by both peritoneal macrophages (maximal response 554 +/- 97 U of activity) and peripheral blood monocytes (maximal response 478 +/- 81 U of activity). We observed enhanced TNF-alpha release by peritoneal macrophages from women with endometriosis, compared with those without endometriosis, at a concentration of 10(4) ng/mL of TSST-1 (704 +/- 134 versus 354 +/- 103 U of activity; P less than .05). These data support the theory that the metabolic and physiologic derangements of perimenstrual toxic shock syndrome may be partially mediated by TNF-alpha released by peritoneal macrophages as a result of exposure to TSST-1.

Successful treatment of focal hepatic candidiasis in a patient with acute myeloid leukaemia

A 38-year-old woman with acute myeloid leukaemia developed focal hepatic candidiasis. Ultrasonography and computerised tomography revealed the hepatic lesion and definite diagnosis was established by percutaneous liver biopsy. The use of a cumulative dose of 6.6 g of amphotericin B in combination with 5-fluorocytosine resulted in successful eradication of the fungus. The difficulties in making an antemortem diagnosis are well recognised and optimal therapy of the condition remains to be defined.

Development of gamma-glutamylcysteine synthetase and oxoprolinase in rat kidney

gamma-Glutamylcysteine synthetase is present in barely detectable amounts in foetal kidney. Its activity starts to increase in postnatal life. In contrast, oxoproline is already found in significant quantities in the foetal tissue. Both enzymes show marked elevation in activities during the weaning period.

Transverse section imaging of mean clearance time

Transverse sections representing the magnitude of clearance rates or the mean transit time of radionuclide flow through known volumes of interest are computed from angular projections. First the integrated counts for all time intervals at each projection bin for each angle are computed. These modified projection sums are convolved with a filter and backprojected to form an integrated event image. A second image is formed by backprojected the sum over time of the projected values for each angle weighted time. The ratio of the second image to the first image gives a mean clearance time image with high signal to noise and accuracy after thresholding to remove noise in zero-flow regions. The algorithm is verified by computer simulations and has a major benefit in the savings of computational time by a factor of 10 for anticipated clinical studies of brain and kidney blood flow and lung ventilation and perfusion.