Probing the global potential energy minimum of (CH2O)2: THz absorption spectrum of (CH2O)2 in solid neon and para-hydrogen.

The true global potential energy minimum configuration of the formaldehyde dimer (CH2O)2, including the presence of a single or a double weak intermolecular CH⋯O hydrogen bond motif, has been a long-standing subject among both experimentalists and theoreticians as two different energy minima conformations of Cs and C2h symmetry have almost identical energies. The present work demonstrates how the class of large-amplitude hydrogen bond vibrational motion probed in the THz region provides excellent direct spectroscopic observables for these weak intermolecular CH⋯O hydrogen bond motifs. The combination of concentration dependency measurements, observed isotopic spectral shifts associated with H/D substitutions and dedicated annealing procedures, enables the unambiguous assignment of three large-amplitude infrared active hydrogen bond vibrational modes for the non-planar Cs configuration of (CH2O)2 embedded in cryogenic neon and enriched para-hydrogen matrices. A (semi)-empirical value for the change of vibrational zero-point energy of 5.5 ± 0.3 kJ mol-1 is proposed for the dimerization process. These THz spectroscopic observations are complemented by CCSD(T)-F12/aug-cc-pV5Z (electronic energies) and MP2/aug-cc-pVQZ (force fields) electronic structure calculations yielding a (semi)-empirical value of 13.7 ± 0.3 kJ mol-1 for the dissociation energy D0 of this global potential energy minimum.

Competition between weak OH⋯π and CH⋯O hydrogen bonds: THz spectroscopy of the C2H2-H2O and C2H4-H2O complexes.

THz absorption spectra have been recorded for the weakly bound molecular complexes of H2O with C2H4 and C2H2 embedded in cryogenic neon matrices at 2.8 K. The observation and assignment of a large-amplitude acceptor OH librational mode of the C2H2-H2O complex at 145.5 cm-1 confirms an intermolecular CH⋯O hydrogen-bonded configuration of C2v symmetry with the H2O subunit acting as the hydrogen bond acceptor. The observation and assignment of two large-amplitude donor OH librational modes of the C2H4-H2O complex at 255.0 and 187.5 cm-1, respectively, confirms an intermolecular OH⋯π hydrogen-bonded configuration with the H2O subunit acting as the hydrogen bond donor to the π-cloud of C2H4. A (semi)-empirical value for the change of vibrational zero-point energy of 4.0-4.1 kJ mol-1 is proposed and the combination with quantum chemical calculations at the CCSD(T)-F12b/aug-cc-pVQZ level provides a reliable estimate of 7.1 ± 0.3 kJ mol-1 for the dissociation energy D0 of the C2H4-H2O complex. In addition, tentative assignments for the two strongly infrared active OH librational modes of the ternary C2H4-HOH-C2H4 complex having H2O as a doubly OH⋯π hydrogen bond donor are proposed at 213.6 and 222.3 cm-1. The present findings demonstrate that the relative stability of the weak hydrogen bond motifs is not entirely rooted in differences of electronic energy but also to a large extent by differences in the vibrational zero-point energy contributions arising from the class of large-amplitude intermolecular modes.

In vitro Monocyte IL-6 Secretion Levels Following Stimulation with Autologous Spheroids Derived from Tumour or Benign Mucosa Predict Long-term Survival in Head and Neck Squamous Cell Carcinoma Patients.

MCP-1/IL-6 in vitro monocyte secretion upon coculture with autologous fragment spheroids was studied in relation to patient 5- and 10-year overall survival rates in head and neck squamous cell carcinoma (HNSCC) patients (n = 65) diagnosed between 1998 and 2005, nine of whom had an human papilloma virus (HPV) tumour infection. The spheroids were harvested from malignant or benign tissue during primary surgery. Two weeks following surgery, freshly isolated autologous monocytes and benign or malignant spheroids were cocultured 24 h in vitro. The IL-6 secretion was expressed as a fraction of the lipopolysaccharide (LPS) response from the same batch of monocytes. HPV status was obtained by employing PCR analyses of primary diagnostic blocks. IL-6/MCP-1 response levels were not found to be dependent on HPV infection status. MCP-1 secretion did not predict prognosis, nor did in vitro IL-6 monocyte background or LPS-stimulated IL-6 secretion. At 5-year observation, dichotomized IL-6 levels following monocyte coculture, with both malignant and benign spheroids, showed a strong trend towards predicting survival, that is a low monocyte malignant coculture response showed a survival of 31 ± 17 versus 58 ± 17% with a high such response (P = 0.057). When studying monocyte IL-6 coculture responses evaluating benign and malignant spheroid results statistically together, a prediction of survival up to 10 years was found (hazard ratio = 0.48; confidence interval = 0.24-0.96; P < 0.05) with double low IL-6 responses. This survival prediction was also present after an adjustment for HPV tumour infection status. In conclusion, monocyte IL-6 in vitro secretion in cocultures with autologous spheroids/serum from HNSCCs predicted 5- and 10-year survivals, both with and without tumour HPV tumour adjustment.

Spectroscopic identification of ethanol-water conformers by large-amplitude hydrogen bond librational modes.

The far-infrared absorption spectra have been recorded for hydrogen-bonded complexes of water with ethanol embedded in cryogenic neon matrices at 2.8 K. The partial isotopic H/D-substitution of the ethanol subunit enabled by a dual inlet deposition procedure enables the observation and unambiguous assignment of the intermolecular high-frequency out-of-plane and the low-frequency in-plane donor OH librational modes for two different conformations of the mixed binary ethanol/water complex. The resolved donor OH librational bands confirm directly previous experimental evidence that ethanol acts as the O⋯HO hydrogen bond acceptor in the two most stable conformations. In the most stable conformation, the water subunit forces the ethanol molecule into its less stable gauche configuration upon dimerization owing to a cooperative secondary weak O⋯HC hydrogen bond interaction evidenced by a significantly blue-shift of the low-frequency in-plane donor OH librational band origin. The strong correlation between the low-frequency in-plane donor OH librational motion and the secondary intermolecular O⋯HC hydrogen bond is demonstrated by electronic structure calculations. The experimental findings are further supported by CCSD(T)-F12/aug-cc-pVQZ calculations of the conformational energy differences together with second-order vibrational perturbation theory calculations of the large-amplitude donor OH librational band origins.

The influence of large-amplitude librational motion on the hydrogen bond energy for alcohol-water complexes.

The far-infrared absorption spectra have been recorded for hydrogen-bonded complexes of water with methanol and t-butanol embedded in cryogenic neon matrices at 2.8 K. The partial isotopic substitution of individual subunits enabled by a dual inlet deposition procedure provides for the first time unambiguous assignments of the intermolecular high-frequency out-of-plane and low-frequency in-plane donor OH librational modes for mixed alcohol-water complexes. The vibrational assignments confirm directly that water acts as the hydrogen bond donor in the most stable mixed complexes and the tertiary alcohol is a superior hydrogen bond acceptor. The class of large-amplitude donor OH librational motion is shown to account for up to 5.1 kJ mol(-1) of the destabilizing change of vibrational zero-point energy upon intermolecular OHO hydrogen bond formation. The experimental findings are supported by complementary electronic structure calculations at the CCSD(T)-F12/aug-cc-pVTZ level of theory.

The effect of hydrogen bonding on torsional dynamics: a combined far-infrared jet and matrix isolation study of methanol dimer.

The effect of strong intermolecular hydrogen bonding on torsional degrees of freedom is investigated by far-infrared absorption spectroscopy for different methanol dimer isotopologues isolated in supersonic jet expansions or embedded in inert neon matrices at low temperatures. For the vacuum-isolated and Ne-embedded methanol dimer, the hydrogen bond OH librational mode of the donor subunit is finally observed at ~560 cm(-1), blue-shifted by more than 300 cm(-1) relative to the OH torsional fundamental of the free methanol monomer. The OH torsional mode of the acceptor embedded in neon is observed at ~286 cm(-1). The experimental findings are held against harmonic predictions from local coupled-cluster methods with single and double excitations and a perturbative treatment of triple excitations [LCCSD(T)] and anharmonic. VPT2 corrections at canonical MP2 and density functional theory (DFT) levels in order to quantify the contribution of vibrational anharmonicity for this important class of intermolecular hydrogen bond vibrational motion.

Communication: THz absorption spectrum of the CO2-H2O complex: observation and assignment of intermolecular van der Waals vibrations.

Terahertz absorption spectra have been recorded for the weakly bound CO2-H2O complex embedded in cryogenic neon matrices at 2.8 K. The three high-frequency van der Waals vibrational transitions associated with out-of-plane wagging, in-plane rocking, and torsional motion of the isotopic H2O subunit have been assigned and provide crucial observables for benchmark theoretical descriptions of this systems' flat intermolecular potential energy surface. A (semi)-empirical value for the zero-point energy of 273 ± 15 cm(-1) from the class of intermolecular van der Waals vibrations is proposed and the combination with high-level quantum chemical calculations provides a value of 726 ± 15 cm(-1) for the dissociation energy D0.

Co-culture of head and neck squamous cell carcinoma spheroids with autologous monocytes predicts prognosis.

Co-culture of monocytes with autologous fragment (F) spheroids originating from malignant (M) tumour or benign (B) control mucosa of head and neck squamous cell carcinoma (HNSCC) yields interleukin (IL)-6 and monocyte chemo-attractant protein (MCP)-1 secretion. This study investigates the association between this cytokine co-culture response and prognosis. Analysis of IL-6 and MCP-1 content of supernatants from monocytes in vitro co-culture with autologous MF- or BF-spheroids was investigated in a cohort of HNSCC patients (n = 65) diagnosed between 1998 and 2005, all of whom were treated with curative intent by primary surgery. The IL-6 response was expressed as a fraction of the lipopolysaccharid response of the same batch of monocytes. Recurrence, survival and causes of death were then established following the second part of 2005. MCP-1 levels did not predict prognosis. We found that increased levels of IL-6 from autologous monocytes in co-culture with MF-spheroids predicted recurrence with a hazard ratio (HR) of 1.5 [confidence interval (CI): 1.01-2.60; P = 0.05] and co-culture with BF-spheroids and monocytes predicted recurrence (HR = 4.17; CI: 1.54-11.29; P = 0.005). The same results where obtained in addition with TNM stage of the patients. Simultaneous analysis of BF- and MF-spheroid co-culture IL-6 responses as well as adjustment for age and TNM stage of the patients allowed prediction of total survival (HR = 3.1; CI: 1.11-8.56; P = 0.03) based on BF co-culture levels. IL-6 secreted upon in vitro co-culture with monocytes and BF-spheroids predicts recurrence and prognosis, whereas co-culture with monocytes and MF-spheroids predicts recurrence.

The effect of tracheostomy on outcome in intensive care unit patients.

BACKGROUND: Percutaneous dilatation tracheostomy (PDT) is increasingly being used in the intensive care unit (ICU), and has probably increased the number of procedures performed. The primary aim of this study was to document the short- and long-term outcome of patients with a tracheostomy performed during an ICU stay. METHODS: Patients in our ICU who underwent an unplanned tracheostomy between 1997 and 2003 were included in this analysis. The type of tracheostomy (PDT or surgical tracheostomy) and time of the procedure were registered prospectively in our ICU database. Survival was followed using the People's Registry of Norway and morbidity data from the individual hospital record. These patients were also compared with a group of ICU patients ventilated for more than 24 h, but managed without a tracheostomy. We also compared patients who had early tracheostomy (less than median time to procedure) with those who had late tracheostomy. RESULTS: Of the 2844 admissions (2581 patients), unplanned tracheostomy was performed during 461 admissions (16.2%) on 454 patients (17.6%). The median time to tracheostomy was 6 days. The ICU, hospital and 1-year mortality rates were 10.8, 27.1 and 37.2%, respectively, significantly less than those of the group ventilated without tracheostomy. The median time to decannulation was 14 days. Patients who had early tracheostomy had a more favourable long-term survival than those who had late tracheostomy. No procedure-related mortality was registered. CONCLUSIONS: In our ICU, having a tracheostomy performed was associated with a favourable long-term outcome with regard to survival, and early tracheostomy improved survival in addition to consuming less ICU resources.

Gene expression profile in oral squamous cell carcinomas and matching normal oral mucosal tissues from black Africans and white Caucasians: the case of the Sudan vs. Norway.

Expression profile of 588 known genes relating to tumour biology, was examined between oral squamous cell carcinomas (OSCCs) and matching normal oral mucosal tissues (NOMTs) obtained from Sudanese (n=11) and Norwegian (n=11) patients. cDNA probes were synthesised from total RNA and hybridised with the Atlas human cancer cDNA expression array membranes. RT-PCR and immunohistochemistry were applied to confirm the expression pattern of a subset of the 588 genes. Differences in expression of the genes examined were found between the OSCCs and the NOMTs on the Atlas membranes. Several of these genes were either up- or down-regulated 1.6-fold or higher in the OSCCs compared to the NOMTs in the cases from the two populations. We found that 181 (31%) and 195 (33%) genes were either up-regulated or down-regulated in the OSCCs from the Sudan and Norway, respectively. From the total number of genes (n=376) found expressed in the OSCCs investigated from the two countries, 53 genes (14%) showed common expression profile [35 (66%) were up-regulated and 18 (34%) were down-regulated] and 70 genes (19%) showed opposite regulation status. Results of the RT-PCR and immunohistochemistry confirmed the hybridisation data. These findings may provide an OSCCs-specific gene expression profile in patients from the two countries, suggesting that alterations of 123 genes are common in these OSCCs regardless of ethnic differences or other socio-cultural risk factors between the patients from the two countries. The findings might further suggest that specific genes are frequently involved in these OSCCs, which may provide novel clues as diagnostic, prognostic biomarkers and/or targets for therapy. The Atlas human cancer cDNA expression array technique can be useful to examine and describe the expression profile of known genes frequently involved in OSCCs from different populations.

Mechanisms for monocyte activation in co-culture with autologous tumor spheroids.

Biopsies from carcinoma tissue and benign control mucosa from head and neck squamous cell carcinoma patients were used to establish fragment (F)-spheroids in vitro. We have previously shown that autologous monocytes co-cultured with F-spheroids in vitro secrete interleukin (IL)-6 upon 24h in co-culture. Presently, the aim was to study the mechanisms of this monocyte secretion. Paraformaldehyde (0.1% for 2min) or actinomycin-D (1 microg/ml for 24h) pre-treatment of the F-spheroids abolished the monocyte IL-6 co-culture response. Addition of glucose (100mM) or mannose (100mM), and to some extent galactose (100mM), but not fructose (100mM) to the co-cultures, partly inhibited the monocyte IL-6 co-culture response, but such addition did not inhibit the in vitro monocyte lipopolysaccharide (LPS)-generated IL-6 secretion. When mannose was added to the co-cultures, monocyte IL-6 mRNA expression was eradicated in malignant co-cultures and reduced to a low level in benign co-cultures. Addition of mouse anti-human beta(1)-integrin (anti-CD29) antibody (2 microg/ml) diminished the IL-6 co-culture response but not the monocyte LPS-generated IL-6 response. In conclusion, the monocyte IL-6 co-culture response is dependent on live spheroids and to some extent on direct contact with the F-spheroids, possibly via lectin-like receptor(s), the mannose receptor and beta(1)-integrin.

Voice results in patients with T1a glottic cancer treated by radiotherapy or endoscopic measures.

Early squamous cell carcinomas of the glottis can be treated effectively by means of surgery or external beam radiotherapy. The curability rate is about the same for both treatment modalities, but differing results have been reported regarding functional results. We selected 24 patients from a larger group of patients who had been treated for T1a glottic laryngeal cancer without the involvement of the anterior commissure. Fifteen patients were treated endoscopically and nine by radiotherapy. During a routine control videolaryngostroboscopy at an outpatient clinic, an objective and a subjective voice analysis were performed. The objective and subjective voice analyses showed no differences between the two treatment modalities. Videolaryngostroboscopy showed a significantly more pronounced glottic wave at the side that was originally affected by the tumour in the radiotherapy group. This difference disappeared when we looked at both vocal cords. Significant differences between the two treatment modalities were not found in any of the other parameters. Thus, this study shows no difference in the voice quality of patients treated by irradiation or by endoscopy. Therefore, the post-treatment voice quality is not a reason to favour radiotherapy for small T1a glottic squamous cell cancers without involvement of the anterior commissure.

Monocyte and monocyte-derived macrophage secretion of MCP-1 in co-culture with autologous malignant and benign control fragment spheroids.

This study was performed in order to determine how monocytes and macrophages in co-culture with autologous head and neck squamous cell carcinoma (HNSCC) tumor tissue regulate the secretion of monocyte chemotactic protein-1 (MCP-1). The levels of MCP-1 were measured when autologous monocytes or monocyte-derived macrophages (MDMs) were co-cultured in vitro with autologous fragment (F)-spheroids established from HNSCC tumors or benign mucosa serving as control. MCP-1 secretion from co-culture stimulated monocytes and MDMs was increased compared to spontaneous MCP-1 secretion. With prolonged co-culture, MDMs showed a steady-state MCP-1 secretion above background levels for up to 96 h, even with change of co-culture media every 24 h. Addition of an anti-MCP-1 antibody to the medium decreased co-culture-induced monocyte IL-6 secretion. Addition of lipopolysaccharide (LPS) (1 [microg/ml) reduced MCP-1 secretion compared to spontaneous secretion in monocyte cultures. F-spheroids also secrete MCP-1, but at insignificant levels compared to the MCP-1 secretion from monocytes and MDMs. MCP-1 secretion from monocytes/MDMs is regulated differently when co-culture stimulation is compared to LPS-stimulation. Monocytes and MDMs expressed MCP-1 mRNA at a high level in all tested conditions: stimulated in co-culture, not stimulated or stimulated with LPS, indicating post-transcriptional regulation of MCP-1 secretion. The secretion of MCP-1 from tumor-derived F-spheroids, and the maintenance of co-culture MCP-1 secretion from MDMs in vitro, suggests that tumor-associated macrophages are a source of MCP-1 in HNSCC tumors.

Human autologous monocytes and monocyte-derived macrophages in co-culture with carcinoma F-spheroids secrete IL-6 by a non-CD14-dependent pathway.

The secretion of interleukin (IL)-1 beta, IL-6 and tumour necrosis factor (TNF)-alpha were compared when freshly isolated autologous monocytes or monocytederived macrophages (MDMs) were co-cultured in vitro with autologous fragment (F)-spheroids established from a series of head and neck squamous cell carcinoma (HNSCC) patients. F-spheroids were generated from the malignant tumour (M-spheroids) or from benign mucosa (B-spheroids) from which the tumour originated control. If monocytes maturated towards MDMs before co-culture, the IL-6 secretion declined dependent on the extent of the MDM maturation by both M- and B-spheroid stimulation. When MDMs maturated in continuous co-culture, a steady-state secretion of IL-6 continued for several days but diminished when the culture medium was changed every 24 h. No co-culture-induced IL-1 beta or TNF-alpha was determined. Both the cytokine secretion and the mRNA gene expression revealed a different monocyte/MDM activation when co-culture and lipopolysaccharide (LPS)-stimulation were compared. Addition of anti-CD14 (10 microg/ml) decreased monocyte LPS-stimulated, but increased monocyte co-culture stimulated IL-6 secretion. In conclusion, M- and B-spheroids similarly stimulated monocytes and to a lesser extent MDMs. MDMs that maturated with F-spheroids present, retained responsiveness at the monocyte level. Co-culture-induced monocyte stimulation, as measured by IL-6 secretion, was not dependent on activation via the CD14 molecule.

Monocytes secrete interleukin-6 when co-cultured in vitro with benign or malignant autologous fragment spheroids from squamous cell carcinoma patients.

Biopsies from tumour and benign mucosa were removed from patients with head and neck squamous-cell carcinoma (HNSCC), chopped into cubes and transferred to a nonadhesive culture system where in vitro fragment (F)-spheroids were established. The F-spheroids stabilized within 14 days of culture in vitro with epithelial cells and fibroblasts on the surface. F-spheroids were co-cultured with freshly isolated autologous monocytes. The monocytes of 10 of 11 patients secreted interleukin (IL)-6 at a level similar to that of the average monocyte endotoxin-stimulated response. Secreted IL-1beta or tumour necrosis factor-alpha (TNF-alpha) levels greater than 0.1 times the endotoxin-stimulated secretion were determined in one and two of the 11 co-culture experiments, respectively. This different monocyte response to F-spheroids compared with endotoxin stimulation was also present at the mRNA expression level. HNSCC monocytes secreted no IL-6 after co-culture with autologous fibroblasts. When monocytes and F-spheroids were cultured separated by a semipermeable membrane, the IL-6 supernatant level was only approximately 25% of that observed during co-culture with direct contact. F-spheroids secreted only trace amounts of IL-6. In conclusion, monocytes of HNSCC patients generally secrete IL-6, but not IL-1beta or TNF-alpha, after stimulation with epithelial-associated components of F-spheroids upon direct contact and in part by a soluble substance.

Peripheral blood T-lymphocyte and monocyte function and survival in patients with head and neck carcinoma.

OBJECTIVES/HYPOTHESIS: To determine if the T-lymphocyte and monocyte functions of peripheral blood mononuclear cells (PBMCs) from patients with head and neck squamous cell carcinomas (HNSCC) are predictive factors for outcome. STUDY DESIGN: A prospective study describing the outcome, as to total survival and death by disease after at least 40 months observation, of 81 previously untreated male HNSCC patients in relation to PBMC T-lymphocyte and monocyte function. METHODS: T-lymphocyte mitogenesis and the cytokine level in culture supernatants of PBMC as well as monocytes were analyzed. These parameters were related to survival by Cox regression and Kaplan-Meier survival analysis. RESULTS: When patients with high versus low T-lymphocyte mitogen-stimulated proliferations were compared, a decreased proliferation was seen to be related to worse outcome. The predictive value of T-lymphocyte proliferation was shown to be an independent prognostic factor when adjusted for stage and stratified for anatomic location in survival analysis. The predictive value was also retained when the serum values of the major serum proteins and hormones and scores based on the smoking and alcohol history were added to the survival analysis with lymphocyte proliferation. Supernatant levels of gamma-interferon, interleukin (IL)-2, or IL-4 in PBMC cultures were not related to outcome. Monocyte function measured by endotoxin-stimulated IL-1beta, IL-6, IL-12, and tumor necrosis factor-alpha secretion did not relate to outcome of the patients. CONCLUSION: The PBMC T-lymphocyte-stimulated proliferation is an independent prognostic factor for male HNSCC patients.

Ex vivo interleukin (IL)-1 beta, IL-6, IL-12 and tumor necrosis factor-alpha responsiveness with monocytes from patients with head and neck carcinoma.

Seventy newly diagnosed Caucasian male patients with head and neck squamous cell carcinomas (HNSCC) were included in the study. All patients were less than 80 years of age, with no cachexia or auto-immune disease, and they were not taking immuno-active medications. Monocytes from these patients were cultured in vitro and supplemented with autologous serum under ex vivo conditions or cultured with serum-free medium. Comparison was made to monocytes from 59 patients with benign HN diseases. Similar physical activity levels prior to testing as well as a minimum stress load were ensured in both groups. Increased monocyte supernatant levels were determined under ex vivo conditions of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumor necrosis factor (TNF)-alpha, but not of interleukin-12 (IL-12) with endotoxin stimulated monocytes of HNSCC patients compared to control conditions. Increased monokine levels were not present with mononuclear cell cultures stimulated with a T-cell general stimulatory agent or with purified monocytes not specifically stimulated. With endotoxin-stimulated monocytes under in vitro conditions, an increased supernatant was shown for TNF-alpha, but not IL-6. With serum from the different patients cultured with monocytes employed from a healthy control, no difference between the groups was shown in the IL-6 and TNF-alpha response to endotoxin stimulation. The differences in IL-1 beta and TNF-alpha, but not IL-6 levels were differentiated statistically from the smoking and alcohol histories of the patients. These findings suggest that the function of monocytes in general, and thus possibly all mononuclear phagocyte system cells in HNSCC patients, are altered.

Peripheral blood mononuclear cell (PBMC) responsiveness in patients with head and neck cancer in relation to tumour stage and prognosis.

We have previously shown an increased T lymphocyte and monocyte responsiveness in peripheral blood mononuclear cells (PBMC) from patients with head and neck squamous cell carcinoma (HNSCC) compared with PBMC from control patients. This study reports T lymphocyte function of PBMC of 81 patients with HNSCC dependent on disease stage and prognosis. Males with HNSCC under 80 years of age without cachexia, with no auto-immune disease or previous cancer and on no immuno-active medication were included at the time of diagnosis of disease. The follow-up was for at least 18 months. When cells from patients with early vs late stage disease according to the T, N or T + N stage of HNSCC were compared, decreased in vitro mitogen-stimulated and spontaneous T cell proliferation was seen with increasing tumour stage. When patients were studied according to disease-specific survival, a decreased T lymphocyte mitogen-stimulated proliferation was observed to be associated with a poorer prognosis. No changes in prognosis were noticed related to decreased gamma-IFN, IL-2 or IL-4 level of the supernatants of the T lymphocyte-stimulated PBMC in vitro cultures. With stratification for disease stage, we determined that PBMC in vitro T lymphocyte-stimulated proliferation predicted outcome for the HNSCC patients. The results were similar for both laryngeal and oral cavity/pharyngeal cancers. The present investigation provides evidence to support the idea that the relationship between HNSCC and the immune system of the host may provide clinically useful information about prognosis.

Disease stage related in vitro responsiveness of peripheral blood T-lymphocytes in patients with head and neck carcinoma.

The in vitro responsiveness of peripheral blood mononuclear cells (PBMC) T lymphocytes was studied in 81 patients with limited or extended head and neck squamous cell carcinoma (HNSCC), as judged by T, N and T + N stages. Patients included in the study were males below 80 years of age, without auto-immune disease or cachexia, who were not taking any immuno-active medication at the time of diagnosis. The patients were divided into groups according to TNM stage T0-2 vs T3-4, N0-1 vs N2-3 or T + N0-3 vs T + N4-7. When cells from patients with early and late stage, according to T, N or T + N stage, were compared, we found a decreased level of mitogen stimulated T-cells and decreased spontaneous proliferation with increasing disease stage. The same was true if the in vitro mitogenesis of T-cells was analysed separately, depending on the laryngeal or oral cavity/pharyngeal origin of the patients' tumours. If the patients were divided into two groups based on N stage, decreased gamma-interferon, and to some extent interleukin (IL-2), but not IL-4 levels, were found to be related to the disease stage.

In vitro T-lymphocyte function in head and neck cancer patients.

T-lymphocyte cell function was studied in vitro in peripheral blood mononuclear cells (PBMC) from 61 male patients with head and neck squamous cell carcinomas compared to 46 control patients. Patients older than 80 years or with reduced tumor-related performance status as measured by Karnofsky score less than 75 were excluded. In contrast to previous similar studies, control subjects ensured a minimum stress load by sampling all patients on the day of either diagnostic or therapeutic surgery. PBMC were separated by density-gradient centrifugation and subsequently cultured with autologous sera in vitro. The mitogen concanavalin A (Con A), which stimulates all T-cell clones, was employed. Findings showed that increased Con A stimulation and PBMC proliferation occurred with PBMC from cancer patients compared to that from control patients. In contrast, no differences could be detected with respect to the stimulated supernatant level of interleukin-2, interleukin-4 or interferon-gamma between the groups. These results suggest that T-lymphocytes from PBMC are generally affected by neoplastic disease through either a supporting cell or serum factor.