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P Rhys-Evans

Publications and source records attributed to P Rhys-Evans.

34 records · Page 2Linked to original sources
PubMed2000

Expression and regulation of c-ERBB ligands in human head and neck squamous carcinoma cells.

We recently reported that multiple c-erbB ligands differentially modulate in vitro proliferation, invasion and expression of matrix metalloproteinases in human head and neck squamous carcinoma cells (HNSCC). In order to evaluate further the importance of c-erbB ligands in tumor progression, the expression and regulation of this growth factor family in HNSCC cells was studied. We demonstrate that mRNAs for the 6 major c-erbB ligands, namely, epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), betacellulin (BTC), heparin-binding epidermal growth factor-like growth factor (HB-EGF), amphiregulin (AR) and heregulin (HRG), are expressed in a large panel of HNSCC cell lines. In addition to TGF-alpha, other ligands (notably BTC and HRG-beta1) are involved in the autocrine growth regulation of these cells. Each c-erbB ligand when applied exogenously, induced mRNA expression of both itself and the remaining family members and a differential response in the kinetics of induction was found. HB-EGF and HRG mRNAs were induced rapidly (within 1 hr) and to a greater extent (3.2-6.2- and 4.8-7. 3-fold increase) than TGF-alpha, BTC and AR mRNAs (1.6-2.7, 1.8-3.6- and 1.6-4.2-fold, respectively). This pattern was observed for all inducing ligands tested. Analysis of mRNA stability, and concurrent treatment with BTC (as an inducing ligand) and cycloheximide (to inhibit protein synthesis) suggested both transcriptional and post-transcriptional regulatory mechanisms. These results support and extend previous observations of c-erbB receptor signaling as a critical element in the pathogenesis and progression of HNSCC, and emphasize the role of autocrine ligand production.

Amphiregulin↗
PubMed2000

Overexpression of epidermal growth factor receptor in human head and neck squamous carcinoma cell lines correlates with matrix metalloproteinase-9 expression and in vitro invasion.

Numerous reports have shown an association between overexpression of the epidermal growth factor receptor (EGFR), and poor prognosis in head and neck squamous cell carcinomas (HNSCC), however, the underlying mechanisms are still unclear. In the present study, we set out to determine whether EGFR expression was associated with in vitro invasive capacity in a panel of four established and ten newly derived HNSCC lines. Ten of the cell lines expressed high levels of EGFR as determined by a ligand-binding assay and dot blot analysis, whereas the remaining four showed weak overexpression or normal levels of EGFR. The ability of cells to invade through Matrigel was found to be higher in the EGFR overexpressing cell lines (p < 0. 0001). Expression levels of matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, MMP-10, MMP-11, MMP-13, MT1-MMP) and tissue inhibitors of MMP (TIMP-1, TIMP-2) were evaluated by semiquantitative RT-PCR, substrate zymography and western blot. We found a strong positive correlation between EGFR levels and the expression of MMP-9 mRNA (r(2) = 0.95; p < 0.0001), MMP-9 enzyme activity (r(2) = 0.8099; p < 0.0001) and an inverse correlation with TIMP-1 (r(2) = 0.48; p = 0.0059). In six selected HNSCC lines, in vitro invasion was assayed in the presence of an anti-EGFR monoclonal antibody, ICR62. A significant reduction of invasion in four selected EGFR-overexpressing cell lines was found with 30 nM ICR62 (from 50% to 70%; p < 0.001) but there was no effect in two cell lines with normal EGFR levels. Our results show that the in vitro invasive phenotype of HNSCC lines correlates with high EGFR and MMP-9 expression, and it is therefore suggested that the EGFR signaling pathway might play an important role in the invasive behavior of HNSCC via specific upregulation of MMP-9 and downregulation of TIMP-1.

Carcinoma, Squamous Cell↗
PubMed2000

Epidermal growth factor-like ligands differentially up-regulate matrix metalloproteinase 9 in head and neck squamous carcinoma cells.

Head and neck squamous cell carcinomas (HNSCCs) are characterized by a marked propensity for local invasion and dissemination to cervical lymph nodes, with distant metastases developing in 30-40% of cases. Overexpression of the epidermal growth factor receptor (EGFR/c-erbB-1) and/or its ligands and high levels of certain matrix metalloproteinases (MMPs) have been associated with poor prognosis. The aim of this study was to examine the effects of EGFR ligands on gelatinase expression and invasion in HNSCC cell lines. We tested epidermal growth factor (EGF), transforming growth factor alpha, betacellulin, heparin-binding EGF, and amphiregulin and measured expression of gelatinases MMP-9 and MMP-2 in an established squamous carcinoma cell line (Detroit-562) and in two cell lines newly derived from patients with head and neck cancers (SIHN-005A and SIHN-006). Incubation of the cell lines with EGF-like ligands up-regulated MMP-9 (but not MMP-2) expression as measured by semiquantitative reverse transcription-PCR in a dose-dependent manner, with the effects being most marked in cells with high EGFR levels and undetectable in cells with low levels. Maximum stimulation was obtained in a concentration range of 10-100 nM. In addition, we confirmed by zymography that gelatinolytic activity consistent with MMP-9 (Mr 92,000) was up-regulated in parallel with increases in gene expression. Betacellulin (which binds both to EGFR and c-erbB-4 receptors) consistently increased MMP-9 expression and activation to a significantly greater degree than the other four ligands when tested at equimolar concentrations. In parallel with MMP-9 up-regulation, all EGF-like ligands increased tumor cell invasion through Matrigel in in vitro Transwell assays. These activities were independent of ligand effects on cell proliferation. Antagonist (ICR62) or agonist (ICR9) anti-EGFR monoclonal antibodies, respectively, inhibited or potentiated MMP-9 activity and tumor cell invasion induced by all ligands. Furthermore, a monoclonal antibody that neutralizes MMP-9 activity (Abl) also inhibited ligand-induced invasion of HNSCC. We confirmed that tumor cell lines used in these studies (and a larger series not reported here) generally expressed multiple c-erbB receptors and ligands. These results indicate that autocrine or paracrine signaling through EGFR potentiates the invasive potential of HNSCC via the selective up-regulation and activation of MMP-9. Furthermore, ligands such as betacellulin (which is commonly expressed in HNSCC), which can bind to and activate other c-erbB receptors, may be especially potent in this regard.

Antibodies, Monoclonal↗
PubMed2000

Vascular endothelial growth factor family members are differentially regulated by c-erbB signaling in head and neck squamous carcinoma cells.

Aberrant expression of tyrosine kinases such as c-erbB and EGFR contributes to the progression of head and neck squamous cell carcinomas (HNSCCs). One mechanism may be potentiation of angiogenesis, since upregulation of vascular endothelial growth factor (VEGF) expression by activation of epidermal growth factor receptor (EGFR) and/or c-erbB-2 has been described. Firstly, we demonstrated expression of all 4 members of the VEGF family in a panel of 15 HNSCC cell lines which over-express one or more c-erbB receptors. We then explored the regulatory roles of three major ligands with different selectivity of binding to c-erbB receptors (namely transforming growth factor-alpha (TGF-alpha), betacellulin (BTC) and heregulin-beta1 (HRG-beta1)) on VEGF-A, B, C and D expression in selected HNSCC lines. Using semi-quantitative reverse transcription-PCR, we showed that all three c-erbB ligands up-regulated VEGF-A mRNA (all isoforms) and VEGF-C (BTC max at 1-10 nM; TGF-alpha and HRG-beta1 max at 10-100 nM) but had no effect on VEGF-B. Interestingly, all ligands simultaneously down-regulated the expression of VEGF-D mRNA. A monoclonal antibody (mAb) which blocks EGFR ligand binding (ICR62) down-regulated the basal levels of VEGF-A (all isoforms) and VEGF-C, had no detectable effects on VEGF-B and increased VEGF-D. ICR62 also reversed the effects of all three erbB ligands (TGF-alpha, BTC and HRG-beta1) on VEGF-A, VEGF-C and VEGF-D expression. An anti-c-erbB-2 mAb (ICR12) showed similar effects on basal or ligand-modulated expression of VEGF in these cell lines, although to a lesser extent. Our results reveal that the four VEGF genes are regulated by c-erbB signaling pathways in a strikingly different manner, suggesting that they serve distinct, although perhaps complimentary (VEGF-A and VEGF-C) or antagonistic (VEGF-D) functions. The EGFR and c-erbB-2 signaling pathway(s) plays a role in VEGF regulation in HNSCC, although EGFR would appear to be dominant in this cell type.

Antibodies, Monoclonal↗
PubMed2000

Investigating lymphadenopathy--report on the first 12 months of the lymph node diagnostic clinic at the Royal Marsden Hospital.

The lymph node diagnostic clinic was set up at the Royal Marsden Hospital to provide a direct access service for general practitioners. In the first year 82 patients were seen. The malignancy pick-up rate was 19.5% which compares very favourably to rates in breast and colorectal clinics. Patient and general practitioner satisfaction with the service was high.

Adolescent↗
PubMed1999

Differential modulation of proliferation, matrix metalloproteinase expression and invasion of human head and neck squamous carcinoma cells by c-erbB ligands.

Evidence suggests that there is an association between the abnormal expression of members of the c-erbB receptor tyrosine kinase family and poor prognosis in head and neck squamous cell carcinomas (HNSCC). Until now, the relative contributions of different c-erbB ligands to HNSCC progression have not been clearly defined. In this paper we examined the effects of ligands with different c-erbB receptor specificities in terms of their stimulation of HNSCC proliferation, expression of matrix metalloproteinases (MMPs) and invasion. Heregulin-beta1 (HRG-beta1; selective c-erbB3/B4 ligand) was found to stimulate proliferation in the majority of cell lines, whereas epidermal growth factor (EGF; EGFR ligand) and betacellulin (BTC; EGFR/B4 ligand) induced variable responses. All three ligands up-regulated multiple MMPs including collagenases, stromelysins, matrilysin and gelatinase B (MMP-9) but had minimal or no effects on gelatinase A (MMP-2), MT1-MMP and tissue inhibitors of MMPs (TIMPs). MMP-9 mRNA was induced to a higher level than other MMPs, although with slower kinetics. HRG-beta1 was less active than EGF and BTC at the optimal concentration (relative potency of EGF:BTC:HRG = 3:4:1). In vitro invasion through Matrigel was also increased by all three ligands in proportion to their MMP up-regulation. A specific anti-EGFR monoclonal antibody (mAb ICR62) inhibited MMP up-regulation, migration and invasion induced by all three ligands, whereas an anti-c-erbB-2 mAb ICR12 inhibited mitogenic and motogenic responses following ligand stimulation but had no effect on MMP expression. These results suggest that c-erbB ligands may differentially potentiate the invasive phenotype of HNSCC via co-operative induction of cell proliferation, migration and proteolysis. The EGFR signalling pathway appears to be the dominant component controlling the proteolytic and invasive phenotype in HNSCC, whereas the c-erbB-2 signalling pathway is responsible, in part, for the mitogenic and motogenic effects of ligands.

Antibodies, Monoclonal↗
PubMed1998

Excision and low-dose radiotherapy for refractory laryngeal granuloma.

Laryngeal granulomas are uncommon lesions of an inflammatory origin. They are conventionally managed by simple excision with the occasional use of adjuvant treatment depending on the aetiological factors. Unfortunately, recurrences can occur, requiring repeated excision. Some lesions are refractory to this approach and alternative management approaches include excision and immediate adjuvant radiotherapy. The use of radiotherapy in the management of benign disease can be limited by the risk of induction of late malignancy and informed consent of a patient must include an assessment of this risk. We describe a case of refractory laryngeal granuloma successfully treated by excision and immediate radiotherapy in a patient occupationally dependent upon his voice.

Combined Modality Therapy↗
PubMed1997

Cisplatin and 5-fluorouracil for symptom control in advanced salivary adenoid cystic carcinoma.

Adenoid cystic carcinoma is a relatively rare tumour which arises in the parotid and submandibular salivary glands. Initial management is surgical, often with post-operative radiotherapy, but local relapse is common and distant metastasis not infrequent. Chemotherapy is generally reserved for cases where symptoms are not controlled by other means, since the tumour is slow growing and the response rate frequently disappointing. Cisplatin and 5-fluorouracil (5-FU) both show single agent activity in this disease but had not been previously investigated in combination. All patients referred for palliative chemotherapy of metastatic, symptomatic, histologically confirmed adenoid cystic carcinoma between November 1990 and February 1994 were considered for this study. The drugs were administered as follows: cisplatin 100 mg/m2 with appropriate pre- and post-hydration and 5-FU on a 4-day schedule of 1 g/m2/day. A total of 11 patients (7 male, 4 female) with median age 53 years (range 34-69) received 46 courses of chemotherapy (median four, range one to six). All patients had prior surgery and 8 had previously received radiotherapy. There were no objective responses of > 50% reduction in tumour size. 3 patients had a minor response and two progressed on treatment. The symptomatic response rate, however, was 64%, which compares favourably with other previously reported regimens. Toxicity was manageable. The median time to tumour progression was 9 months (range 0-38) and median survival was 12 months (range 1-65). This cisplatin/5-FU regimen would appear to produce a low rate of objective response but useful palliative benefits in advanced symptomatic adenoid cystic carcinoma. Prior series suggest that a higher objective response rate may be possible with a platinum/anthracycline/fluorouracil combination, and investigation of such a regimen is warranted.

Adult↗
PubMed1997

Chemotherapy for symptom control in recurrent squamous cell carcinoma of the head and neck.

BACKGROUND: The role of chemotherapy in patients with recurrent squamous cell carcinomas of the head and neck (SCCHN) is unclear. The aim of this study was to assess the ability of combination chemotherapy to control symptoms in this setting. PATIENTS AND METHODS: Using a prospectively accrued database all patients referred for chemotherapy with symptomatic relapse following surgery were identified. Objective response was recorded using standard criteria and maximum symptom response was assessed retrospectively from case notes using a published scoring scale. RESULTS: A total of 57 (median age 56, range 37-85) patients were studied who had received mainly cisplatin/5-fluorouracil combinations. Thirty-seven had previously received radiotherapy. Fifty-two patients had evaluable disease; 18 (35%) had objective responses (14 PRs and 4 CRs). There were a total of 103 symptoms recorded with eight different individual symptoms. Forty-four (43%) symptoms improved on treatment, 52 (50%) were unchanged and 7 (7%) worsened. The number of patients with improvement in the most frequently recorded symptoms were as follows: pain 11/28 (39%), swelling 12/23 (52%) and dysphagia 6/18 (33%). Sixty-seven percent of patients with objective response also had an improvement in their symptoms but a significant proportion (33%) of non-responders had a symptomatic response. Lack of objective response was not correlated with worsening symptoms. Grade 3/4 toxicity was uncommon (6%-17%) and there were no toxic deaths. A majority of patients (82%) experienced either no change or an improvement in performance status. CONCLUSION: These results demonstrate that chemotherapy improves many of the symptoms associated with recurrent SCCHN, without deterioration in performance status. Symptomatic improvement is more likely if there is evidence of significant tumour shrinkage, but even non-responding patients can benefit.

Adult↗
PubMed1993

Head and neck sarcomas: prognostic factors and implications for treatment.

One hundred and thirty patients with soft tissue sarcoma of the head and neck were treated at the Royal Marsden Hospital between 1944 and 1988. Pathological review was possible in 103 of these cases; only pathologically reviewed cases have been analysed. The median age at presentation was 36 years, and 53% were male. Four had neurofibromatosis type I, and one previous bilateral retinoblastoma. Six had undergone previous radiotherapy, 12 to 45 years prior to developing sarcoma. The tumours were < or = 5 cm in 78% of cases and high grade in 48%. Only one patient presented with lymph node metastases and only one with distant metastases (to lung). Malignant fibrous histiocytoma was the commonest histological type, occurring in 30 cases. The overall 5 year survival was 50% (95% CI 39-60). Local tumour was the cause of death in 63% of cases and 5 year local control was only 47% (95% CI 36-58) with local recurrence occurring as late as 15 years after treatment. The only favourable independent prognostic factor for survival was the ability to perform surgery (other than biopsy), with or without radiotherapy, as opposed to radiotherapy alone (hazard ratio 0.39; P = 0.003). Only one patient had a biopsy with no further treatment. Favourable independent prognostic factors for local control at 5 years were site (tumours of the head as opposed to the neck, hazard ratio 0.42; P = 0.02) and modality of treatment (combined surgery and radiotherapy compared to either alone, hazard ratio 0.31; P = 0.002). Patients in the combined modality and single treatment modality groups were well balanced for T stage, grade and tumour site. The patients in the combined treatment group had less extensive surgery, yet their local recurrence-free survival was longer. Unlike soft tissue sarcomas at other sites, those in the head and neck region more often cause death by local recurrence. The addition of radiotherapy to surgery may result in longer local recurrence-free survival.

Adult↗
PubMed1989

Recent experience with reconstructive surgery following major glossectomy.

In an attempt to monitor the impact of new reconstructive procedures and shifting interest away from routine preoperative radiotherapy, we have reviewed the 81 patients undergoing major glossectomy and reconstruction (MGR) at the Royal Marsden Hospital, London and Surrey, England, between 1975 and 1987. While there were four marginal and 13 major reconstructive failures, 11 of the latter were successfully managed with an alternative flap, thus providing a prompt and effective palliation for most of these patients. An evolution in our choice of reconstructive procedures as well as a recent trend toward using MGR as a primary therapeutic modality were noted. Data relating to speech following reconstruction and diet rehabilitation were encouraging, particularly with the use of the latissimus dorsi flap. Survival following MGR, however, was dismal due to early local and regional recurrence.

Adult↗
PubMedDate not supplied

Characterization of ten newly-derived human head and neck squamous carcinoma cell lines with special reference to c-erbB proto-oncogene expression.

Ten human head and neck squamous carcinoma (HNSCC) cell lines were established in order to study the role of c-erbB signaling pathways in HNSCC progression. Five cell lines were derived from primary tumors at four different sites, and five were from lymph node metastases in the neck. Two pairs of lines were derived from the primary tumor and metastatic lymph node in the same patient. Basic characteristics including morphology, doubling time, phenotypes, cytogenetic profiles and tumorigenicity in nude mice were described. We examined the expression of c-erbB receptors and ligands in early passage new HNSCC lines and compared with five long-term established lines, normal keratinocytes and fibroblasts. Amplification of c-erbB-1 (EGFR) gene was observed in only one cell line whereas no amplification of other c-erbB genes was found. Overexpression of EGFR, c-erbB-2, c-erbB-3 and c-erbB-4 mRNAs was observed in 10, 14, 10 and 8 out of 15 head and neck cell lines respectively. Overexpression of c-erbB-3 and c-erbB-4 was more frequently observed in newly derived HNSCC lines than in long-established cell lines. The majority of tumor cells also expressed multiple c-erbB ligands. One selected cell line, SIHN-006, was shown to exhibit tyrosine phosphorylation via all four receptors. These new cell lines could provide a useful experimental model to study the co-operative signaling of type I tyrosine kinase receptors in HNSCC progression.

Adult↗