The effects inhibiting the proliferation of cancer cells by far-infrared radiation (FIR) are controlled by the basal expression level of heat shock protein (HSP) 70A

We developed a tissue culture incubator that can continuously irradiate cells with far-infrared radiation (FIR) of wavelengths between 4 and 20 μm with a peak of 7–12 μm, and found that FIR caused different inhibiting effects to five human cancer cell lines, namely A431 (vulva), HSC3 (tongue), Sa3 (gingiva), A549 (lung), and MCF7 (breast). Then, in order to make clear the control system for the effect of FIR, the gene expression concerned to the inhibition effect by FIR were analyzed. In consequence, basal expression level of HSP70A mRNA was higher in A431 and MCF7 cells than in the FIR-sensitive HSC3, Sa3, and A549 cells. Also, the over expression of HSP70 inhibited FIR-induced growth arrest in HSC3 cells, and an HSP70 siRNA inhibited the proliferation of A431 cells by irradiation with FIR. These results indicate that the effect of a body temperature range of FIR suppressing the proliferation of some cancer cells is controlled by the basal expression level of heat shock protein (HSP) 70A. This finding suggested that FIR should be very effective medical treatment for some cancer cells which have a low level of HSP70. Still more, if the level of HSP70 in any cancer of a patient was measured, the effect of medical treatment by FIR can be foreseen for the cancer

Down-regulation of GRP78 is associated with the sensitivity of chemotherapy to VP-16 in small cell lung cancer NCI-H446 cells

<p>Abstract</p> <p>Background</p> <p>Chemotherapy resistance remains a major obstacle for the treatment of small cell lung cancer (SCLC). Glucose-regulated protein 78 (GRP78), an endoplasmic reticulum chaperone, plays a critical role in chemotherapy resistance in some cancers. However, whether the suppression of the chaperone can enhance the sensitivity of chemotherapy in SCLC is still unclear.</p> <p>Methods</p> <p>The SCLC NCI-H446 cells were divided into three groups: BAPTA-AM→A23187-treated group, A23187-treated group and control-group. Immunofluorescence, western blot and RT-PCR were used to assess the expression of GRP78 at both protein and mRNA levels. Cell apoptosis and the cell cycle distributions of the cells were analyzed by flow cytometry in order to evaluate the therapeutic sensitivity to VP-16.</p> <p>Results</p> <p>The expression of GRP78 at both protein and mRNA levels in the BAPTA-AM→A23187-treated cells dramatically decreased as compared to that in both A23187-treated and control groups. After treatment by VP-16, the percentage of apoptotic cells in BAPTA-AM→A23187-treated cells were: 33.4 ± 1.01%, 48.2 ± 1.77%, 53.0 ± 1.43%, 56.5 ± 2.13%, respectively, corresponding to the concentrations of BAPTA-AM 10, 15, 25, 40 μM, which was statistically significant high in comparison with the A23187-treated group and untreated-group (7.18 ± 1.03% and 27.8 ± 1.45%, respectively, p < 0.05). The results from analysis of cell cycle distribution showed that there was a significantly decreased in G₁phase and a dramatically increased in S phase for the BAPTA-AM→A23187-treated cells as compared with the untreated cells.</p> <p>Conclusion</p> <p>BAPTA-AM is a strong inhibitor of GRP78 in the NCI-H446 cell line, the down-regulation of GRP78 can significantly increase the sensitivity to VP-16. The suppression of GRP78 may offer a new surrogated therapeutic approach to the clinical management of lung cancer.</p

Induction of cancer-specific cytotoxicity towards human prostate and skin cells using quercetin and ultrasound

Bioflavonoids, such as quercetin, have recently emerged as a new class of chemotherapeutic drugs for the treatment of various cancer types, but are marred by their low potency and poor selectivity. We report that a short application of low-frequency ultrasound selectively sensitises prostate and skin cancer cells against quercetin. Pretreatment of cells with ultrasound (20 kHz, 2 W cm−2, 60 s) selectively induced cytotoxicity in skin and prostate cancer cells, while having minimal effect on corresponding normal cell lines. About 90% of the viable skin cancer cell population was lost within 48 h after ultrasound-quercetin (50 μM) treatment. Ultrasound reduced the LC50 of quercetin for skin cancer cells by almost 80-fold, while showing no effect on LC50 for nonmalignant skin cells

Novel Mitochondrial Substrates of Omi Indicate a New Regulatory Role in Neurodegenerative Disorders

The mitochondrial protease OMI (also known as HtrA2) has been implicated in Parkinson's Disease (PD) and deletion or protease domain point mutations have shown profound neuropathologies in mice. A beneficial role by OMI, in preserving cell viability, is assumed to occur via the avoidance of dysfunctional protein turnover. However relatively few substrates for mitochondrial Omi are known. Here we report our identification of three novel mitochondrial substrates that impact metabolism and ATP production. Using a dual proteomic approach we have identified three interactors based upon ability to bind to OMI, and/or to persist in the proteome after OMI activity has been selectively inhibited. One candidate, the chaperone HSPA8, was common to each independent study. Two others (PDHB subunit and IDH3A subunit) did not appear to bind to OMI, however persisted in the mito-proteome when OMI was inhibited. Pyruvate dehydrogenase (PDH) and isocitrate dehydrogenase (IDH) are two key Kreb's cycle enzymes that catalyse oxidative decarboxylation control points in mitochondrial respiration. We verified both PDHB and IDH3A co-immunoprecipitate with HSPA8 and after elution, were degraded by recombinant HtrA2 in vitro. Additionally our gene expression studies, using rotenone (an inhibitor of Complex I) showed Omi expression was silenced when pdhb and idh3a were increased when a sub-lethal dose was applied. However higher dose treatment caused increased Omi expression and decreased levels of pdhb and idh3a transcripts. This implicates mitochondrial OMI in a novel mechanism relating to metabolism

Heat Shock Protein-27, -60 and -90 expression in gastric cancer: association with clinicopathological variables and patient survival

<p>Abstract</p> <p>Background</p> <p>Heat shock proteins (HSPs) are ubiquitous, highly conserved proteins across all the species and play essential roles in maintaining protein stability within the cells under normal conditions, while preventing stress-induced cellular damage. HSPs were also overexpressed in various types of cancer, being associated with tumor cell proliferation, differentiation and apoptosis. The aim of the present study was to evaluate the clinical significance of HSP -27, -60, and -90 expression in gastric carcinoma.</p> <p>Methods</p> <p>HSP -27, -60, and -90 proteins expression was assessed immunohistochemically in tumoral samples of 66 gastric adenocarcinoma patients and was statistically analyzed in relation to various clinicopathological characteristics, tumor proliferative capacity and patients' survival.</p> <p>Results</p> <p>HSP-27, -60, -90 proteins were abundantly expressed in gastric adenocarcinoma cases examined. HSP-27 expression was significantly associated with tumor size (pT, P = 0.026), the presence of organ metastases (pM, P = 0.046) and pStage (P = 0.041), while HSP-27 staining intensity with nodal status (pN, P = 0.042). HSP-60 expression was significantly associated with patients' sex (P = 0.011), while HSP-60 staining intensity with patients' age (P = 0.027) and tumor histopathological grade (P = 0.031). HSP-90 expression was not associated with any of the clinicopathological parameters examined; however, HSP-90 staining intensity was significantly associated with tumor size (pT, P = 0.020). High HSP-90 expression was significantly associated with longer overall survival times in univariate analysis (log-rank test, P = 0.033), being also identified as an independent prognostic factor in multivariate analysis (P = 0.026).</p> <p>Conclusion</p> <p>HSP-27, -60, and -90 were associated with certain clinicopathological parameters which are crucial for the management of gastric adenocarcinoma patient. HSP-90 expression may also be an independent prognostic indicator in gastric adenocarcinoma patients.</p

Heat stress causes spatially-distinct membrane re-modelling in K562 leukemia cells

Cellular membranes respond rapidly to various environmental perturbations. Previously we showed that modulations in membrane fluidity achieved by heat stress (HS) resulted in pronounced membrane organization alterations which could be intimately linked to the expression and cellular distribution of heat shock proteins. Here we examine heat-induced membrane changes using several visualisation methods. With Laurdan two-photon microscopy we demonstrate that, in contrast to the enhanced formation of ordered domains in surface membranes, the molecular disorder is significantly elevated within the internal membranes of cells preexposed to mild HS. These results were compared with those obtained by anisotropy, fluorescence lifetime and electron paramagnetic resonance measurements. All probes detected membrane changes upon HS. However, the structurally different probes revealed substantially distinct alterations in membrane heterogeneity. These data call attention to the careful interpretation of results obtained with only a single label. Subtle changes in membrane microstructure in the decision-making of thermal cell killing could have potential application in cancer therapy

Haploinsufficiency of the E3 Ubiquitin Ligase C-Terminus of Heat Shock Cognate 70 Interacting Protein (CHIP) Produces Specific Behavioral Impairments

The multifunctional E3 ubiquitin ligase CHIP is an essential interacting partner of HSP70, which together promote the proteasomal degradation of client proteins. Acute CHIP overexpression provides neuroprotection against neurotoxic mitochondrial stress, glucocorticoids, and accumulation of toxic amyloid fragments, as well as genetic mutations in other E3 ligases, which have been shown to result in familial Parkinson's disease. These studies have created a great deal of interest in understanding CHIP activity, expression and modulation. While CHIP knockout mice have the potential to provide essential insights into the molecular control of cell fate and survival, the animals have been difficult to characterize in vivo due to severe phenotypic and behavioral dysfunction, which have thus far been poorly characterized. Therefore, in the present study we conducted a battery of neurobehavioral and physiological assays of adult CHIP heterozygotic (HET) mutant mice to provide a better understanding of the functional consequence of CHIP deficiency. We found that CHIP HET mice had normal body and brain weight, body temperature, muscle tone and breathing patterns, but do have a significant elevation in baseline heart rate. Meanwhile basic behavioral screens of sensory, motor, emotional and cognitive functions were normative. We observed no alterations in performance in the elevated plus maze, light-dark preference and tail suspension assays, or two simple cognitive tasks: novel object recognition and spontaneous alternation in a Y maze. Significant deficits were found, however, when CHIP HET mice performed wire hang, inverted screen, wire maneuver, and open field tasks. Taken together, our data indicate a clear subset of behaviors that are altered at baseline in CHIP deficient animals, which will further guide whole animal studies of the effects of CHIP dysregulation on cardiac function, brain circuitry and function, and responsiveness to environmental and cellular stress

The Early Clinical Features of Dengue in Adults: Challenges for Early Clinical Diagnosis

Dengue infection in adults has become increasingly common throughout the world. As most of the clinical features of dengue have been described in children, we undertook a prospective study to determine the early symptoms and signs of dengue in adults. We show here that, overall, dengue cases presented with high rates of symptoms listed in the WHO 1997 or 2009 classification schemes for probable dengue fever thus resulting in high sensitivities of these schemes when applied for early diagnosis. However, symptoms such as myalgia, arthralgia, retro-orbital pain and mucosal bleeding were less frequently reported in older adults. This trend resulted in reduced sensitivity of the WHO classification schemes in older adults even though they showed increased risks of hospitalization and severe dengue. Instead, we suggest that older adults who present with fever and leukopenia should be tested for dengue, even in the absence of other symptoms. This could be useful for early clinical diagnosis in older adults so that they can be monitored and treated for severe dengue, which is especially important when an antiviral drug becomes available

Forced, not voluntary, exercise effectively induces neuroprotection in stroke

Previous treadmill exercise studies showing neuroprotective effects have raised questions as to whether exercise or the stress related to it may be key etiologic factors. In this study, we examined different exercise regimens (forced and voluntary exercise) and compared them with the effect of stress-only on stroke protection. Adult male Sprague-Dawley rats (n = 65) were randomly assigned to treatment groups for 3 weeks. These groups included control, treadmill exercise, voluntary running wheel exercise, restraint, and electric shock. Levels of the stress hormone, corticosterone, were measured in the different groups using ELISA. Animals from each group were then subjected to stroke induced by a 2-h middle cerebral artery (MCA) occlusion followed by 48-h reperfusion. Infarct volume was determined in each group, while changes in gene expression of stress-induced heat shock proteins (Hsp) 27 and 70 were compared using real-time PCR between voluntary and treadmill exercise groups. The level of corticosterone was significantly higher in both stress (P < 0.05) and treadmill exercise (P < 0.05) groups, but not in the voluntary exercise group. Infarct volume was significantly reduced (P < 0.01) following stroke in rats exercised on a treadmill. However, the amelioration of damage was not duplicated in voluntary exercise, even though running distance in the voluntary exercise group was significantly (P < 0.01) longer than that of the forced exercise group (4,828 vs. 900 m). Furthermore, rats in the electric shock group displayed a significantly increased (P < 0.01) infarct volume. Expression of both Hsp 27 and Hsp 70 mRNA was significantly increased (P < 0.01) in the treadmill exercise group as compared with that in the voluntary exercise group. These results suggest that exercise with a stressful component, rather than either voluntary exercise or stress alone, is better able to reduce infarct volume. This exercise-induced neuroprotection may be attributable to up-regulation of stress-induced heat shock proteins 27 and 70