Prognostic value of oxygen consumption and ventilatory equivalent slope in female candidates referred for heart transplantation--experience of a single Asian center

BACKGROUND

Ventilatory equivalent (ventilation/CO2 production, VE/VCO2) slope has been suggested to be a much more accurate predicator than peak oxygen consumption (VO2) during exercise for prognosis in patients with heart failure. However, patients tested were predominately male.

METHODS

To investigate whether peak VO2 and VE/VCO2 slope predict the prognosis of female patients with heart failure, we retrospectively collected data of 39 female candidates referred for heart transplantation (HTx) from 2004 to 2011. Both peak VO2 and VE/VCO2 slope were obtained from the results of an exercise pulmonary function test. The outcome was death or mechanical devices implantation or HTx. Logistic regression was used for data analysis.

RESULTS

Mean age and heart failure survival score were 55.8 ± 13.7 years and 7.3 ± 0.7, respectively. Each increment of VE/VCO2 slope decreased 2-year event-free rate (odds ratio [OR] = 0.88, 95% confidence interval [CI] = 0.79 to 0.98) in the female group. The predictions of VE/VCO2 slope for 1-year event-free survival did not reach statistical significance (OR = 0.92, 95% CI = 0.84 to 1.00). On the other hand, peak VO2 was not a strong predictor for 1- and 2-year event-free survival (OR = 1.22 and 1.16, 95% CI = 0.96 to 1.55 and 0.94 to 1.44, respectively).

CONCLUSIONS

Impairment in exercise ventilation holds a clinical and long-term prognostic impact in female patients with heart failure. The role of peak VO2 during exercise in prognostic prediction among the cohort should be further investigated.

Does airway integrated nasal packing after septal surgery improve body oxygenation?

BACKGROUND

Airway integrated nasal packing reportedly improves body oxygenation after septal surgery. This randomized controlled study examined the effect of airway integrated nasal packing on oxygen saturation.

METHODS

Eighty patients with septal deviation and hypertrophic turbinate were randomly divided into two groups: Group 1 patients were postoperatively packed with airway integrated Nasopore, and Group 2 patients were postoperatively packed with Nasopore without airway integration. The haemodynamic parameters and SpO2 (oxyhemoglobin saturation levels when measured using pulse oximetry) were sequentially checked. Nasal pain sensations were recorded using a visual analog scale.

RESULTS

SpO2 was not significantly different between Groups 1 and 2. Nasal pain levels were significantly higher in Group 1 than in Group 2 at both 4 (p = 0.034) and 6 (p = 0.001) hours postoperatively. There were no significant differences between the two groups in the incidences of septal haematoma, perforation, or bleeding, or in sequentially checked heart rate, mean blood pressure, or respiration rate.

CONCLUSION

It was not evident that integrated airways improved the reduction of SpO2. However, Group 1 patients, with integrated airways, had more pain than did Group 2 patients, without integrated airways.

EVIDENCE LEVEL

1b.

Promising antimicrobial capability of thin film metallic glasses

Thin film metallic glasses (TFMGs) are demonstrated to exhibit excellent surface flatness, high corrosion resistance and satisfactory hydrophobic properties. Moreover, the antimicrobial and biocompatibility abilities of TFMGs are examined and the results are compared with the behavior of pure Ag and 316L stainless steel. Three TFMGs, Al48Ag37Ti15, Zr54Ti35Si11, and Zr59Ti22Ag19, are prepared by sputtering to assess the antimicrobial performance against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, which are the most common nosocomial infection pathogens. Experimental results show that the antimicrobial effect of the Al- or Ag-containing AlAgTi and ZrTiAg TFMGs is similar to that of the pure Ag coating. The ZrTiSi TFMG with no Ag or Al shows poor antimicrobial capability. The physical properties of highly smooth surface and hydrophobic nature alone are not sufficient to result in promising antimicrobial ability. The chemical metal ion release still plays a major role, which should be born in mind in designing biomedical devices.

The impact of abnormal muscle tone from hemiplegia on reclining wheelchair positioning: a sliding and pressure evaluation

BACKGROUND

Little is known about the influence of existing muscle tone abnormality on the sitting posture of stroke patients in reclining wheelchairs.

AIM

To investigate the impact of muscle tone abnormality from hemiplegia on the forward sliding and pressure of stroke patients while sitting in reclining wheelchairs.

DESIGN

Experimental study.

SETTING

The Assistive Devices/Technology Center at the Rehabilitation Department of hospital.

POPULATION

14 able-bodied elders and nonambulatory elderly stroke patients with flaccid (N.=12) or spastic hemiplegia (N.=13) participated in this study. Of the 12 patients with flaccid hemiplegia, 8 suffered from left-sided hemiplegia and 4 from right-sided hemiplegia. Of the 13 patients with spastic hemiplegia, 6 suffered from left-sided hemiplegia and 7 from right-sided hemiplegia.

METHODS

We performed 3 reclining cycles in wheelchairs with conventional seats and V-shaped seats for each participant. The sliding along the backrest (BS) plane and the seat (SS) plane, mean sitting pressure (MP), and sacral peak pressure (SPP) of the participants were recorded. The Kruskal-Wallis test was used to compare the difference in BS, SS, MP, and SPP between able-bodied elders and stroke patients.

RESULTS

The BS, SS, and SPP during repetitive reclining were generally greatest in flaccid hemiplegic participants, followed by spastic hemiplegic participants, and finally by able-bodied participants. There was no significant difference in MP among three subject groups on both conventional seats and V-shaped seats in most comparisons. Able-bodied participants' buttocks tended to slide forward on conventional seats but backward on V-shaped seats, whereas hemiplegic participants' buttocks slid forward on both seat types.

CONCLUSION

Stroke patients with flaccid hemiplegia are the most vulnerable to sacral sitting and higher sacral pressure in reclining wheelchairs, followed by patients with spastic hemiplegia. There is a difference in the displacement pattern between participants with normal muscle tone and those with abnormal muscle tone during wheelchair positioning. People who have hemiplegia with spasticity do not have incremental forward sliding with repetitive reclining in the same way as those who have a flaccid hemiplegia.

CLINICAL REHABILITATION IMPACT

The findings are valuable for wheelchair prescription and caregiver education.

Synthesis of an organophilic ZIF-71 membrane for pervaporation solvent separation

For the first time, an organophilic ZIF-71 membrane was prepared and used for pervaporation separation of liquid alcohol-water and dimethyl carbonate-methanol mixtures. The ZIF-71 membrane exhibits good performance in separation of methanol-water and dimethyl carbonate-methanol mixtures.

The role of GABAergic signalling in stress-induced suppression of gonadotrophin-releasing hormone pulse generator frequency in female rats

Stress exerts profound inhibitory effects on reproductive function by suppressing the pulsatile release of gonadotrophin-releasing hormone (GnRH) and therefore luteinising hormone (LH). This effect is mediated in part via the corticotrophin-releasing factor (CRF) system, although another potential mechanism is via GABAergic signalling within the medial preoptic area (mPOA) because this has known inhibitory influences on the GnRH pulse generator and shows increased activity during stress. In the present study, we investigated the role of the preoptic endogenous GABAergic system in stress-induced suppression of the GnRH pulse generator. Ovariectomised oestradiol-replaced rats were implanted with bilateral and unilateral cannulae targeting toward the mPOA and lateral cerebral ventricle, respectively; blood samples (25 μl) were taken via chronically implanted cardiac catheters every 5 min for 6 h for the measurement of LH pulses. Intra-mPOA administration of the specific GABA(A) receptor antagonist, bicuculline (0.2 pmol each side, three times at 20-min intervals) markedly attenuated the inhibitory effect of lipopolysaccharide (LPS; 25 μg/kg i.v.) but not restraint (1 h) stress on pulsatile LH secretion. By contrast, restraint but not LPS stress-induced suppression of LH pulse frequency was reversed by application of the selective GABA(B) receptor antagonist, CGP-35348, into the mPOA (1.5 nmol each side, three times at 20-min intervals). However, intra-mPOA application of either bicuculline or CGP-35348 attenuated the inhibitory effect of CRF (1 nmol i.c.v.) on the pulsatile LH secretion. These data indicate a pivotal and differential role of endogenous GABAergic signalling in the mPOA with respect to mediating psychological and immunological stress-induced suppression of the GnRH pulse generator.

Localized joule heating as a mask-free technique for the local synthesis of ZnO nanowires on silicon nanodevices

We report a mask-free technique for the local synthesis of ZnO nanowires (NWs) on polysilicon nanobelts and polysilicon NW devices. First, we used localized joule heating to generate a poly(methyl methacrylate) (PMMA) nanotemplate, allowing the rapid and self-aligned ablation of PMMA within a short period of time (ca. 5 μs). Next, we used ion-beam sputtering to prepare an ultrathin Au film and a ZnO seed layer; a subsequent lift-off process left the seed layers selectively within the PMMA nanotemplate. Gold nanoparticles and ZnO NWs were formed selectively in the localized joule heating region.

The role of the bed nucleus of the stria terminalis in stress-induced inhibition of pulsatile luteinising hormone secretion in the female rat

The bed nucleus of the stria terminalis (BNST) occupies a central position in the neural circuitry regulating the hypothalamic-pituitary-adrenocortical axis response to stress. The potential role of the BNST in stress-induced suppression of the gondotrophin-releasing hormone (GnRH) pulse generator, the central regulator of the reproductive system, was assessed by examining the effects of micro-infusion of corticotrophin-releasing factor (CRF) or its antagonist into the BNST on pulsatile luteinising hormone (LH) secretion or stress-induced inhibition of LH pulses, respectively. Ovariectomised oestrogen-treated rats were implanted chronically with bilateral cannulae in the dorsolateral BNST and i.v. catheters. CRF (25, 50 or 100 pmol in 200 nl of artificial cerebrospinal fluid) administered bilaterally into the BNST resulted in a dose-dependent decrease in LH pulse frequency, and induced Fos expression in glutamic acid decarboxylase immunostained neurones in the medial preoptic area. These results suggest that the activation of hypothalamic GABAergic neurones in response to intra-BNST administration of CRF may be involved in the suppression of LH pulses. Furthermore, administration of CRF antagonist (280 pmol astressin-B, three times at 20-min intervals) into the BNST effectively blocked the suppression of pulsatile LH secretion in response to restraint (1 h) but not hypoglycaemic (0.25 U insulin/kg, i.v.) stress. These data suggest that CRF innervation of the dorsolateral BNST plays a key, but differential, role in stress-induced suppression of the GnRH pulse generator.

Corticotrophin-releasing factor alters the timing of puberty in the female rat

Puberty is a developmental process that is dependent upon activation of the hypothalamic gonadotrophin-releasing hormone (GnRH) pulse generator. It is well established that the stress neuropeptide, corticotrophin-releasing factor (CRF), has a profound inhibitory action on GnRH pulse generator frequency. Although stress is known to affect the timing of puberty, the role of CRF is unknown. The present study aimed to test the hypothesis that CRF plays a critical role in the timing of puberty. On postnatal day (pnd) 28, female rat pups were chronically implanted with i.c.v. cannulae and received 14 days of administration of either CRF, CRF receptor antagonist (astressin-B) or artificial cerebrospinal fluid via an osmotic mini-pump. A separate group of rats served as nonsurgical controls. As a marker of puberty, rats were monitored for vaginal opening and first vaginal oestrus. Levels of CRF, CRF receptor types 1 and 2 (CRF-R1, CRF-R2) mRNA expression in micropunches of the medial preoptic area (mPOA), hypothalamic paraventricular nucleus (PVN) and arcuate nucleus (ARC) were determined across pubertal development; brain tissue was collected from a naive group of rats on pnd 14, 32, on the day of vaginal opening, and pnd 77 (Adult). Administration of CRF resulted in a delay in the onset of puberty, whereas astressin-B advanced pubertal onset. Additionally, CRF and CRF-R1 mRNA expression was reduced in the mPOA, but not ARC, at puberty. In the PVN, expression of CRF, but not CRF-R1 mRNA, was reduced at the time of puberty. These data support the hypothesis that CRF signalling may play an important role in modulating the timing of puberty in the rat.

Reduced duodenal cytochrome P450 3A protein expression and catalytic activity in patients with cirrhosis

The small intestine and liver express high levels of cytochrome P450 3A (CYP3A), an enzyme subfamily that contributes significantly to drug metabolism. In patients with cirrhosis, reduced metabolism of drugs is typically attributed to decreased liver function, but it is unclear whether drug metabolism in the intestine is also compromised. In this study, we compared CYP3A protein expression and in vitro midazolam hydroxylation in duodenal mucosal biopsies from subjects with normal liver function (controls; n = 20) and subjects with various levels of severity of cirrhosis (n = 23). In samples from subjects with cirrhosis, duodenal CYP3A expression and total midazolam hydroxylation were lower by 47 and 34%, respectively, as compared with samples from controls. Greater decreases in CYP3A expression were seen in subjects with more severe cirrhosis. Therefore, patients with advanced cirrhosis may have greater drug exposure following oral dosing as a result of both impaired liver function and decreased intestinal CYP3A expression and activity.

Laser action in Tb(OH)3/SiO2 photonic crystals

Photonic crystals of Tb(OH)(3)/SiO(2) core/shell nanospheres with different periodicities were used as a resonant cavity to explore laser action. By changing the particle size, the optical stop band of the photonic crystals can be tuned to coincide with the multiple emission bands of terbium ions. An overlap of the stop band on the multiple emissions of the active materials embedded inside the photonic crystals offered a good chance for resonance. Lasing emissions arising from terbium ions occurred near the band edge of the PCs were demonstrated.

Variability of albumin adducts of 1,4-benzoquinone, a toxic metabolite of benzene, in human volunteers

A putative haematotoxic and leukaemogenic metabolite of benzene, 1,4-benzoquinone (1,4-BQ), reacts rapidly with macromolecules. The authors previously characterized levels of the albumin (Alb) adduct (1,4-BQ-Alb) of this reactive species in populations of workers exposed to benzene. Since high levels of 1,4-BQ-Alb were also measured in unexposed workers from those investigations, the current study was initiated to determine potential sources of 1,4-BQ in the general population. A single blood sample was collected from 191 healthy subjects from the Research Triangle area, NC, USA, to determine the baseline 1,4-BQ-Alb levels and contributing sources. The median 1,4-BQ-Alb at baseline was 550?pmol?g(-1) Alb (interquartile range 435-814?pmol?g(-1)). A second blood sample was collected approximately 3 months later from a subgroup of 33 subjects to estimate the within- and between-person variation in 1,4-BQ-Alb. Standardized questionnaires were administered to collect information about demographic, dietary and lifestyle factors. Multiple linear regression models identified several significant contributors to 1,4-BQ-Alb levels, including gender, body mass index (BMI), the gender-BMI interaction, automobile refuelling, smoking status, and consumption of fruit and the artificial sweetener, aspartame. The authors predicted that these background levels of 1,4-BQ-Alb were equivalent to occupational exposures between 1 and 3 parts per million of benzene. Mixed effects linear models indicated that the random variation in adduct levels was about equally divided between and within subjects. The observations indicate that levels of 1,4-BQ-Alb cover a wide range in the general population, and they support the hypotheses that demographic, diet and lifestyle factors are contributing sources.

Relationships between levels of volatile organic compounds in air and blood from the general population

The relationships between levels of volatile organic compounds (VOCs) in blood and air have not been well characterized in the general population where exposure concentrations are generally at parts per billion levels. This study investigates relationships between the levels of nine VOCs, namely, benzene, chloroform, 1,4-dichlorobenzene, ethylbenzene, methyl tert-butyl ether (MTBE), tetrachloroethene, toluene, and m-/p- and o-xylene, in blood and air from a stratified random sample of the general US population. We used data collected from 354 participants, including 89 smokers and 265 nonsmokers, aged 20-59 years, who provided samples of blood and air in the National Health and Nutrition Examination Survey (NHANES) 1999-2000. Demographic and physiological characteristics were obtained from self-reported information; smoking status was determined from levels of serum cotinine. Multiple linear regression models were used to investigate the relationships between VOC levels in air and blood, while adjusting for effects of smoking and demographic factors. Although levels of VOCs in blood were positively correlated with the corresponding air levels, the strength of association (R(2)) varied from 0.02 (ethylbenzene) to 0.68 (1,4-DCB). Also the blood-air relationships of benzene, toluene, ethylbenzene, and the xylenes (BTEX) were influenced by smoking, exposure-smoking interactions, and by gender, age, and BMI, whereas those of the other VOCs were not. Interestingly, the particular exposure-smoking interaction for benzene was different from those for toluene, ethylbenzene, and the xylenes. Whereas smokers retained more benzene in their blood at increasing exposure levels, they retained less toluene, ethylbenzene, and xylenes at increasing exposure levels. Investigators should consider interaction effects of exposure levels and smoking when exploring the blood-air relationships of the BTEX compounds in the general population.

Thallium-201 SPECT predicts response to intensity-modulated radiation therapy for recurrent oral squamous cell carcinoma

The aim of this study was designed to investigate the usefulness of thallium-201 single photon emission computed tomography (SPECT) in predicting response of intensity-modulated radiation therapy (IMRT) for recurrent oral squamous cell carcinoma (OSCC).

PATIENTS, METHODS

Thirty-one patients with histologically proven recurrent OSCC were recruited. Before IMRT, all patients underwent SPECT at 15 min and 120 min after intravenous injection 111 MBq of thallous chloride ((201)Tl). Tumour uptake was measured with the semiquantitative early ratio (ER), delayed ratio (DR), and retention index (RI). The patients were classified into responder (complete response and partial response) and non-responder (stable disease and progressive disease) groups according to the tumour response evaluated by the Response Evaluation Criteria in Solid Tumors guidelines.

RESULTS

As comparing DR and RI between the two groups, both parameters were significantly higher in the responder group. When a DR of 1.75 was used as a cutoff value for the responders, the receiver operating characteristic (ROC) analyses revealed sensitivity and specificity of 79% and 75%, respectively. At a cutoff value for the responders of a RI of 78.5%, the ROC analyses showed sensitivity and specificity of 95% and 83%, respectively.

CONCLUSION

Our results suggest that (201)Tl-SPECT, as measured by the DR or RI has clinical potential in predicting response of IMRT for patients with recurrent OSCC. The ROC curve analyses further suggest that RI may be superior to DR in distinguishing responders from non-responders.

Molecular signatures of metaplastic carcinoma of the breast by large-scale transcriptional profiling: identification of genes potentially related to epithelial-mesenchymal transition

Metaplastic carcinoma of the breast (MCB) is a poorly understood subtype of breast cancer. It is generally characterized by the coexistence of ductal carcinomatous and transdifferentiated sarcomatous components, but the underlying molecular alterations, possibly related to epithelial-mesenchymal transition (EMT), remain elusive. We performed transcriptional profiling using half-a-genome oligonucleotide microarrays to elucidate genetic profiles of MCBs and their differences to those of ductal carcinoma of breasts (DCBs) using discarded specimens of four MCBs and 34 DCBs. Unsupervised clustering disclosed distinctive expression profiles between MCBs and DCBs. Supervised analysis identified gene signatures discriminating MCBs from DCBs and between MCB subclasses. Notably, many of the discriminator genes were associated with downregulation of epithelial phenotypes and with synthesis, remodeling and adhesion of extracellular matrix, with some of them have known or inferred roles related to EMT. Importantly, several of the discriminator genes were upregulated in a mutant Snail-transfected MCF7 cell known to exhibit features of EMT, thereby indicating a crucial role for EMT in the pathogenesis of MCBs. Finally, the identification of SPARC and vimentin as poor prognostic factors reinforced the role of EMT in cancer progression. These data advance our understanding of MCB and offer clues to the molecular alterations underlying EMT.

Ceramide in apoptotic signaling and anticancer therapy

Ceramide, a product of sphingolipid metabolism, is generated in response to various stress stimuli, such as tumor necrosis factor-alpha, CD95/Fas, chemotherapeutic agents, and irradiation. Ceramide may modulate the biochemical and cellular processes that lead to apoptosis. However, the mechanisms by which ceramide regulates apoptotic events are not fully defined. It is believed that the biological effect of ceramide depends on its concentration, the activation or differentiation status of the cell, and the time frame of action. Here, we discuss the metabolism and cell apoptotic signaling of ceramide. The involvement of protein kinases (i.e. PI3K/Akt and GSK-3beta) and protein phosphatases (i.e. PP1 and PP2A), Bcl-2 family proteins, mitochondrial damage, and caspase cascade activation are demonstrated. Further, ceramide and its derivatives have recently been incorporated into strategies for anticancer therapies. An understanding of the apoptotic signaling pathways mediated by ceramide may shed light on its potential for therapeutic intervention.

Air samples versus biomarkers for epidemiology

BACKGROUND

It has been speculated on theoretical grounds that biomarkers are superior surrogates for chemical exposures to air samples in epidemiology studies.

METHODS AND RESULTS

Biomarkers were classified according to their position in the exposure-disease continuum-that is, parent compound, reactive intermediate, stable metabolite, macromolecular adduct, or measure of cellular damage. Because airborne exposures and these different biomarkers are time series that vary within and between persons in a population, they are all prone to measurement error effects when used as surrogates for true chemical exposures. It was shown that the attenuation bias in the estimated slope characterising a log exposure-log disease relation should decrease as the within- to between-person variance ratio of a given set of air or biomarker measurements decreases. To gauge the magnitudes of these variance ratios, a database of 12,077 repeated observations was constructed from 127 datasets, including air and biological measurements from either occupational or environmental settings. The within- and between-person variance components (in log scale, after controlling for fixed effects of time) and the corresponding variance ratios for each set of air and biomarker measurements were estimated. It was shown that estimated variance ratios of biomarkers decreased in the order short term (residence time < or =2 days) > intermediate term (2 days < residence time < or =2 months) > long term biomarkers (residence time >2 months). Overall, biomarkers had smaller variance ratios than air measurements, particularly in environmental settings. This suggests that a typical biomarker would provide a less biasing surrogate for exposure than would a typical air measurement.

CONCLUSION

Epidemiologists are encouraged to consider the magnitudes of variance ratios, along with other factors related to practicality and cost, in choosing among candidate surrogate measures of exposure.

Antibody to severe acute respiratory syndrome (SARS)-associated coronavirus spike protein domain 2 cross-reacts with lung epithelial cells and causes cytotoxicity

Both viral effect and immune-mediated mechanism are involved in the pathogenesis of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection. In this study, we showed that in SARS patient sera there were autoantibodies (autoAbs) that reacted with A549 cells, the type-2 pneumocytes, and that these autoAbs were mainly IgG. The autoAbs were detectable 20 days after fever onset. Tests of non-SARS-pneumonia patients did not show the same autoAb production as in SARS patients. After sera IgG bound to A549 cells, cytotoxicity was induced. Cell cytotoxicity and the anti-epithelial cell IgG level were positively correlated. Preabsorption and binding assays indicated the existence of cross-reactive epitopes on SARS-CoV spike protein domain 2 (S2). Furthermore, treatment of A549 cells with anti-S2 Abs and IFN-gamma resulted in an increase in the adherence of human peripheral blood mononuclear cells to these epithelial cells. Taken together, we have demonstrated that the anti-S2 Abs in SARS patient sera cause cytotoxic injury as well as enhance immune cell adhesion to epithelial cells. The onset of autoimmune responses in SARS-CoV infection may be implicated in SARS pathogenesis.

Sentinel node detection with radiocolloid lymphatic mapping in early invasive cervical cancer

We assessed the feasibility of sentinel lymph node detection using technicium-99 radiocolloid lymphatic mapping for predicting lymph node metastases in early invasive cervical cancer. Thirty patients with cervical cancer (stages IA2-IIA) underwent preoperative lymphoscintigraphy using technicium-99 intracervical injection and intraoperative lymphatic mapping with a handheld gamma probe. After dissection of the sentinel nodes, the standard procedure of pelvic lymph node dissection and radical hysterectomy was performed as usual. The sentinel node detection rate was 100% (30/30). There were seven (23.3%) cases of microscopic lymph node metastases on pathologic analysis. All of them had sentinel node involvement. Therefore, the sensitivity of sentinel node identification for prediction of lymph node metastases was 100%, and no false negative was found. Preoperative lymphoscintigraphy, coupled with intraoperative lymphatic mapping, located the sentinel nodes accurately in our study patients. This sentinel node detection method appears to be feasible for predicting lymph node metastases.

Double-clad Cr4+:YAG crystal fiber amplifier

A novel double-clad Cr4+:YAG crystal fiber is demonstrated by use of a codrawing laser-heated pedestal growth method. Up to 10 dB of gross gain at a wavelength of 1.52 microm is achieved at a pump power of 0.83 W, which, to our knowledge, is the first Cr4+-doped fiber amplifier in the optical fiber communication band.

Elevated serum levels of a c-erbB-2 oncogene product in oral squamous cell carcinoma patients

OBJECTIVES

Amplification of the proto-oncogene c-erbB-2 (HER-2/neu) has been shown to be a prognostic marker in many kinds of cancer including oral squamous cell carcinoma (OSCC). In order to obtain further information on the c-erbB-2 gene product p185, it is necessary to quantify expression levels. In this study we used an enzyme-linked immunosorbent assay (ELISA) for the extracellular domain of p185 to determine whether a soluble oncoprotein fragment can be detected in the serum of OSCC patients.

METHOD

Sera from 84 OSCC patients, 51 breast cancer patients (as positive controls), and 15 healthy controls were assayed in an ELISA. To study c-erbB-2 overexpression in OSCC, and breast cancer tissue samples we used an immunohistochemical technique.

RESULTS

The mean serum value (ng/ml, mean/SD) for the normal controls was 8.46/1.29. We chose the 95% level of normal controls as a cut-off to distinguish individuals with elevated levels. The breast cancer patients' and OSCC patients' serum values were 13.83/6.82 and 13.1/4.56, respectively. Significant differences (P < 0.0001) were observed between normal control and OSCC, normal control and the breast cancer group. Immunohistochemically detectable p185 (intermediate to high) was noted in 30 of 61 OSCC, and 24 of 51 breast cancer patients. There was a trend of association of serum oncoprotein fragment levels with tumor stages, but not with tumor sizes, nodal stages, metastases, and oral habits including betel quid chewing, alcohol drinking and smoking in the OSCC group.

CONCLUSION

The results of the present study raise the possibility that soluble c-erbB-2 protein levels in serum is a useful parameter for monitoring the disease status as well as the effect of therapy on patients with OSCC.