Stem cell concepts in myelodysplastic syndromes: lessons and challenges.

According to the cancer stem cell (CSC) hypothesis, CSCs are the only cancer cells that can give rise to and sustain all cells that constitute a cancer as they possess inherent or acquired self-renewal potential, and their elimination is required and potentially sufficient to achieve a cure. Whilst establishing CSC identity remains challenging in most cancers, studies of low-intermediate risk myelodysplastic syndromes (MDS), other chronic myeloid malignancies and clonal haematopoiesis of indeterminant potential (CHIP) strongly support that the primary target cell usually resides in the rare haematopoietic stem cell (HSC) compartment. This probably reflects the unique self-renewal potential of HSCs in normal human haematopoiesis, combined with the somatic initiating genomic driver lesion not conferring extensive self-renewal potential to downstream progenitor cells. Mutational 'fate mapping' further supports that HSCs are the only disease-propagating cells in low-intermediate risk MDS, but that MDS-propagating potential might be extended to progenitors upon disease progression. The clinical importance of MDS stem cells has been highlighted through the demonstration of selective persistence of MDS stem cells in patients at complete remission in response to therapy. This implies that MDS stem cells might possess unique resistance mechanisms responsible for relapses following otherwise efficient treatments. Specific surveillance of MDS stem cells should be considered to assess the efficiency of therapies and as an early indicator of emerging relapses in patients in clinical remission. Moreover, further molecular characterization of purified MDS stem cells should facilitate identification and validation of improved and more stem cell-specific therapies for MDS.

The use of bisphosphonates in the management of bone involvement from solid tumours and haematological malignancies - a European survey.

Bone metastases in patients with solid tumours (ST) and bone lesions in patients with haematological malignancies (HM) are common. Associated skeletal-related events (SREs) cause severe pain, reduced quality of life and place a burden on health care resources. Bone-targeted agents can reduce the risk of SREs. We evaluated the management of bone metastasis/lesions in five European countries (France, Germany, Italy, Spain and the UK) by an observational chart audit. In total, 881 physicians completed brief questionnaires on 17 193 patients during the observation period, and detailed questionnaires for a further 9303 individuals. Patient cases were weighted according to the probability of inclusion. Although a large proportion of patients with bone metastases/lesions were receiving bisphosphonates, many had their treatment stopped (ST, 19%; HM, 36%) or will never be treated (ST, 18%; HM, 13%). The results were generally similar across the countries, although German patients were more likely to have asymptomatic bone lesions detected during routine imaging. In conclusion, many patients who could benefit from bone-targeted agents do not receive bisphosphonates and many have their treatment stopped when they could benefit from continued treatment. Developing treatment guidelines, educating physicians and increasing the availability of new agents could benefit patients and reduce costs.

Quality of life, support and smoking in advanced lung cancer patients: a qualitative study.

BACKGROUND: Lung cancer is the most common cancer and smoking is the principal cause. Due to poor survival rates, symptom palliation and promotion of health-related quality of life (HRQoL) are primary outcomes for lung cancer patients. Given the established relationship between smoking and lung cancer, patients who have smoked may feel stigmatised or guilty after diagnosis, and more pessimistic about their illness and likely outcomes. This may have adverse implications for HRQoL. OBJECTIVES: We explored HRQoL and support experiences among newly diagnosed patients with advanced lung cancer. DESIGN: Semistructured interviews were conducted with nine patients and analysed using interpretative phenomenological analysis. RESULTS: Patients described the physical, emotional and social impact of disease on HRQoL. Fear of compromising their immune system and adjusting to new relationship roles had a wide-ranging effect on patients' HRQoL. Patients acknowledged links between lung cancer and smoking but some continued to smoke. They were sensitive to the opinions of medical staff about smoking especially those who continued to smoke or recently quit. CONCLUSIONS: We conclude that staff should give clearer advice about the adverse implications of continued smoking. We discuss the potential value of diagnosis as a teachable moment for promoting smoking cessation among patients and family members.

Guidelines for time-to-event end point definitions in sarcomas and gastrointestinal stromal tumors (GIST) trials: results of the DATECAN initiative (Definition for the Assessment of Time-to-event Endpoints in CANcer trials)†.

BACKGROUND: The use of potential surrogate end points for overall survival, such as disease-free survival (DFS) or time-to-treatment failure (TTF) is increasingly common in randomized controlled trials (RCTs) in cancer. However, the definition of time-to-event (TTE) end points is rarely precise and lacks uniformity across trials. End point definition can impact trial results by affecting estimation of treatment effect and statistical power. The DATECAN initiative (Definition for the Assessment of Time-to-event End points in CANcer trials) aims to provide recommendations for definitions of TTE end points. We report guidelines for RCT in sarcomas and gastrointestinal stromal tumors (GIST). METHODS: We first carried out a literature review to identify TTE end points (primary or secondary) reported in publications of RCT. An international multidisciplinary panel of experts proposed recommendations for the definitions of these end points. Recommendations were developed through a validated consensus method formalizing the degree of agreement among experts. RESULTS: Recommended guidelines for the definition of TTE end points commonly used in RCT for sarcomas and GIST are provided for adjuvant and metastatic settings, including DFS, TTF, time to progression and others. CONCLUSION: Use of standardized definitions should facilitate comparison of trials' results, and improve the quality of trial design and reporting. These guidelines could be of particular interest to research scientists involved in the design, conduct, reporting or assessment of RCT such as investigators, statisticians, reviewers, editors or regulatory authorities.

Clonal variegation and dynamic competition of leukemia-initiating cells in infant acute lymphoblastic leukemia with MLL rearrangement.

Distinct from other forms of acute lymphoblastic leukemia (ALL), infant ALL with mixed lineage leukemia (MLL) gene rearrangement, the most common leukemia occurring within the first year of life, might arise without the need for cooperating genetic lesions. Through Ig/TCR rearrangement analysis of MLL-AF4+ infant ALL at diagnosis and xenograft leukemias from mice transplanted with the same diagnostic samples, we established that MLL-AF4+ infant ALL is composed of a branching subclonal architecture already at diagnosis, frequently driven by an Ig/TCR-rearranged founder clone. Some MLL-AF4+ clones appear to be largely quiescent at diagnosis but can reactivate and dominate when serially transplanted into immunodeficient mice, whereas other dominant clones at diagnosis can become more quiescent, suggesting a dynamic competition between actively proliferating and quiescent subclones. Investigation of paired diagnostic and relapse samples suggested that relapses often occur from subclones already present but more quiescent at diagnosis. Copy-number alterations identified at relapse might contribute to the activation and expansion of previously quiescent subclones. Finally, each of the identified subclones is able to contribute to the diverse phenotypic pool of MLL-AF4+ leukemia-propagating cells. Unraveling of the subclonal architecture and dynamics in MLL+ infant ALL may provide possible explanations for the therapy resistance and frequent relapses observed in this group of poor prognosis ALL.

First-line anthracycline-based chemotherapy for angiosarcoma and other soft tissue sarcoma subtypes: pooled analysis of eleven European Organisation for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group trials.

BACKGROUND: Angiosarcoma is a rare subtype of soft tissue sarcoma (STS). Doxorubicinis the standard first-line chemotherapy for advanced STS. It is not known whether angiosarcoma response to anthracycline-based chemotherapy is different to other STS subtypes. METHODS: Pooled data were analysed from 11 prospective randomised and non-randomized European Organisation for Research and Treatment of Cancer (EORTC) clinical trials of first-line anthracycline-based chemotherapy for advanced STS. Baseline patient characteristics, chemotherapy response, progression free survival (PFS) and overall survival (OS) of angiosarcoma patients were compared with other STS patients. Analysis was performed to identify factors prognostic for angiosarcoma response to chemotherapy, PFS and OS. RESULTS: With a median follow-up of 4.2 years, data from 108 locally advanced and metastatic angiosarcoma patients and 2557 patients with other STS histologies were analysed. 25% of angiosarcoma patients had a complete or partial response to chemotherapy compared to 21% for other STS histotypes. The median PFS was 4.9 months and OS 9.9 months, which were not significantly different from other STS histotypes. In univariate analysis, bone metastases were an adverse prognostic factor for OS (hazard ratio (HR) 1.66, 95% confidence interval (CI) 1.03­2.67; p = 0.036). Tumour grade was as an adverse prognostic factor for PFS (HR 1.72, 95% CI 1.01­2.92; p = 0.044) and OS (HR 2.03; 95% CI 1.16­3.56; p = 0.011). Compared to single agent anthracyclines, doxorubicin + ifosfamide was associated with improved PFS (HR 0.53, 95% CI 0.33­0.86; p = 0.010) and OS (HR 0.53, 95% CI 0.32­0.90; p = 0.018). CONCLUSIONS: Angiosarcoma response and survival following first-line anthracycline-based chemotherapy was similar to other STS histotypes. Our analysis provides a useful measure of angiosarcoma response to chemotherapy for comparison with future clinical trials.

The roles of HOXD10 in the development and progression of head and neck squamous cell carcinoma (HNSCC).

BACKGROUND: HOX gene expression is altered in many cancers; previous microarray revealed changes in HOX gene expression in head and neck squamous cell carcinoma (HNSCC), particularly HOXD10. METHODS: HOXD10 expression was assessed by qPCR and immunoblotting in vitro and by immunohistochemistry (IHC) in tissues. Low-expressing cells were stably transfected with HOXD10 and the phenotype assessed with MTS, migration and adhesion assays and compared with the effects of siRNA knockdown in high-HOXD10-expressing cells. Novel HOXD10 targets were identified using expression microarrays, confirmed by reporter assay, and validated in tissues using IHC. RESULTS: HOXD10 expression was low in NOKs, high in most primary tumour cells, and low in lymph node metastasis cells, a pattern confirmed using IHC in tissues. Overexpression of HOXD10 decreased cell invasion but increased proliferation, adhesion and migration, with knockdown causing reciprocal effects. There was no consistent effect on apoptosis. Microarray analysis identified several putative HOXD10-responsive genes, including angiomotin (AMOT-p80) and miR-146a. These were confirmed as HOXD10 targets by reporter assay. Manipulation of AMOT-p80 expression resulted in phenotypic changes similar to those on manipulation of HOXD10 expression. CONCLUSIONS: HOXD10 expression varies by stage of disease and produces differential effects: high expression giving cancer cells a proliferative and migratory advantage, and low expression may support invasion/metastasis, in part, by modulating AMOT-p80 levels.

Vascular-targeted agents for the treatment of angiosarcoma.

PURPOSE: Angiosarcomas are rare, aggressive vascular tumours known to express vascular endothelial growth factor (VEGF), a key pro-angiogenic growth factor. The aim of this study was to determine the potential effects of vascular-targeted agents for the treatment of angiosarcoma, using two human cutaneous angiosarcoma cell lines (ASM and ISO-HAS), and human dermal microvascular endothelial cells (HuDMECs) for comparison. METHODS: Protein arrays were used to assess the expression of angiogenesis-related proteins, and potential drug targets were assessed by ELISA and Western blotting. Response to vascular-targeted agents, including bevacizumab an anti-VEGF antibody, axitinib a VEGF-receptor tyrosine kinase inhibitor, everolimus an mTOR inhibitor, selumetinib a MEK inhibitor and vadimezan a vascular-disrupting agent were compared in functional in vitro cellular assays, including viability, differentiation and migration assays. RESULTS: ASM and ISO-HAS cells expressed a broad range of pro-angiogenic growth factors. ASM and ISO-HAS VEGF expression was significantly increased (p = 0.029) compared with HuDMECs. Striking responses were seen to vadimezan with an IC50 of 90 and 150 µg/ml for ASM and ISO-HAS cells, respectively. Selumetinib inhibited ASM with an IC50 of 1,750 ng/ml, but was not effective in ISO-HAS. Everolimus reduced both ASM and ISO-HAS viable cell counts by 20 % (p < 0.001). Minimal responses were observed to bevacizumab and axitinib in assays with ASM and ISO-HAS cells. CONCLUSIONS: Further studies are warranted to investigate mTOR inhibitors, MEK inhibitors and vascular-disrupting agents for the treatment of angiosarcoma.

Identification of a KIR antisense lncRNA expressed by progenitor cells.

Human NK cells express cell surface class I MHC receptors (killer cell immunoglobulin-like receptor, KIR) in a probabilistic manner. Previous studies have shown that a distal promoter acts in conjunction with a proximal bidirectional promoter to control the selective activation of KIR genes. We report here the presence of an intron 2 promoter in several KIR genes that produce a spliced antisense transcript. This long noncoding RNA (lncRNA) transcript contains antisense sequence complementary to KIR-coding exons 1 and 2 as well as the proximal promoter region of the KIR genes. The antisense promoter contains myeloid zinc finger 1 (MZF-1)-binding sites, a transcription factor found in hematopoietic progenitors and myeloid precursors. The KIR antisense lncRNA was detected only in progenitor cells or pluripotent cell lines, suggesting a function that is specific for stem cells. Overexpression of MZF-1 in developing NK cells led to decreased KIR expression, consistent with a role for the KIR antisense lncRNA in silencing KIR gene expression early in development.

Analysis of circulating angiogenic biomarkers from patients in two phase III trials in lung cancer of chemotherapy alone or chemotherapy and thalidomide.

BACKGROUND: Thalidomide has potent anti-inflammatory and anti-angiogenic properties. It was evaluated in combination with chemotherapy in two randomised placebo-controlled trials in patients with small cell lung cancer (SCLC, n=724) and advanced non-small cell lung cancer (NSCLC, n=722). Neither study demonstrated an improvement in overall survival with the addition of thalidomide to chemotherapy. This study investigated circulating angiogenic biomarkers in a subset of these patients. METHODS: Serial plasma samples were collected in a cohort of patients enrolled in these two trials (n=95). Vascular endothelial growth factor (VEGF), soluble truncated form of VEGF receptor-2 (sVEGFR-2), interleukin-8 (IL-8), tumour necrosis factor-α (TNF-α), basic fibroblast growth factor (bFGF) and soluble intercellular adhesion molecule-1 (sICAM-1) levels were measured by enzyme-linked immunosorbent assays. Results were correlated with patient clinical data including stage, response rate and progression-free survival (PFS). RESULTS: Baseline biomarker levels were not significantly different between SCLC and NSCLC. For pooled treatment groups, limited stage SCLC was associated with lower baseline VEGF (P=0.046), sICAM-1 (P=0.008) and IL-8 (P=0.070) than extensive stage disease. Low baseline IL-8 was associated with a significantly improved PFS in both SCLC and NSCLC (P=0.028), and a greater reduction in IL-8 was associated with a significantly improved tumour response (P=0.035). Baseline angiogenic factor levels, however, did not predict response to thalidomide. CONCLUSION: Circulating angiogenic biomarkers did not identify patients who benefited from thalidomide treatment.

[PET-CT with intravenous contrast in the evaluation of patients with lymphoma. Contribution to diagnostic indications]. / PET-TAC con contraste intravenoso en la valoración de pacientes con linfoma. Aproximación hacia las indicaciones diagnósticas.

AIM: To define the utility of intravenous contrast administration in the PET-CT (PET-CTc) in patients with lymphoma in order to determine its possible indications. MATERIAL AND METHODS: 78 patients with lymphoma were prospectively evaluated. All underwent simultaneous PET-CTc scans in a hybrid system for staging (8), evaluation of response to treatment (29), suspicion of recurrence (9) and complete remission control (48). The PET scan was acquired by a conventional method and the diagnostic CT scan was performed according to radiological protocol. Both examinations were evaluated blinded and independently, analyzing 28 anatomical locations in order to determine the degree of agreement. Final diagnosis was established by the clinician based on the histological study, results of other diagnostic techniques or clinical follow-up. RESULTS: The final result of both techniques were concordant in 87/94 studies (92.5%). A total of 158 (36 FP) pathological locations were detected with PET-CT and 189 (71 FP) with CTc, with 72 locations being discordant between both techniques. Global sensitivity, specificity, PPV and NPV were 93%, 98%, 77% and 99%; and 94%, 97%, 62% and 99%, respectively. CONCLUSIONS: Administration of intravenous contrast does not seem to provide any advantage in the determination of nodal and extranodal disease in lymphoma patients. The low prevalence of disease probably accounts for the limited PPV of both techniques. An increase of our sample size, with a greater homogeneity of the groups, should offer more reliable results.

PET-TAC con contraste intravenoso en la valoración de pacientes con linfoma. Aproximación hacia las indicaciones diagnósticas / PET-CT with intravenous contrast in the evaluation of patients with lymphoma. Contribution to diagnostic indications

ObjetivoDefinir la utilidad de la administración de contraste intravenoso en la PET-TAC (PET-TACc) en pacientes con linfoma, con el fin de determinar sus posibles indicaciones.Material y métodoSe ha valorado prospectivamente a 78 pacientes con linfoma, a los que se les realizó 94 estudios PET-TACc de manera simultánea en un equipo híbrido para estadiaje (8), valoración de respuesta al tratamiento (29), sospecha de recidiva (9) y control en remisión (48). El estudio PET se adquirió de forma convencional y la TACc se realizó según protocolo radiológico.Material y métodoSe valoraron ambas exploraciones, de forma independiente y ciega, analizando 28 localizaciones anatómicas con el fin de determinar la sensibilidad (S), la especificidad (E), el valor predictivo positivo (VPP) y el valor predictivo negativo (VPN), así como el grado de concordancia. El diagnóstico final fue establecido por el clínico atendiendo a la confirmación histológica, al resultado de otras técnicas diagnósticas o al seguimiento clínico.ResultadosAmbas técnicas fueron concordantes en su resultado final en 87/94 estudios (92,5%). Se encontraron 158 (36 falsos positivos [FP]) localizaciones patológicas con PET-TAC y 189 (71 FP) con TACc, siendo 72 discordantes entre ambas técnicas.ResultadosLa S, la E, el VPP y el VPN de la PET-TAC y de la TACc fueron del 93, el 98, el 77 y el 99%, y del 94, el 97, el 62 y el 99%, respectivamente.ConclusionesLa administración de contraste intravenoso no parece aportar ventajas en la determinación de patología ganglionar ni extraganglionar en los pacientes con linfoma. La baja prevalencia de enfermedad probablemente sea la causa del limitado VPP de ambas técnicas. La ampliación de nuestra casuística, con una mayor homogeneidad de los grupos, ofrecerá resultados más fiables(AU9

AimTo define the utility of intravenous contrast administration in the PET-CT (PET-CTc) in patients with lymphoma in order to determine its possible indications.Material and methods78 patients with lymphoma were prospectively evaluated. All underwent simultaneous PET-CTc scans in a hybrid system for staging (8), evaluation of response to treatment (29), suspicion of recurrence (9) and complete remission control (48). The PET scan was acquired by a conventional method and the diagnostic CT scan was performed according to radiological protocol.Material and methodsBoth examinations were evaluated blinded and independently, analyzing 28 anatomical locations in order to determine the degree of agreement. Final diagnosis was established by the clinician based on the histological study, results of other diagnostic techniques or clinical follow-up.ResultsThe final result of both techniques were concordant in 87/94 studies (92.5%). A total of 158 (36 FP) pathological locations were detected with PET-CT and 189 (71 FP) with CTc, with 72 locations being discordant between both techniques.ResultsGlobal sensitivity, specificity, PPV and NPV were 93%, 98%, 77% and 99%; and 94%, 97%, 62% and 99%, respectively.ConclusionsAdministration of intravenous contrast does not seem to provide any advantage in the determination of nodal and extranodal disease in lymphoma patients. The low prevalence of disease probably accounts for the limited PPV of both techniques. An increase of our sample size, with a greater homogeneity of the groups, should offer more reliable results(AU)

Pegfilgrastim for peripheral CD34+ mobilization in patients with solid tumours.

The efficacy of pegfilgrastim+/-chemotherapy for mobilizing stem cells in patients with solid tumours was assessed. In cycle 0, a 14-day prechemotherapy cycle, patients (N=61) were randomized open-label to single doses of pegfilgrastim (6, 12 or 18 mg) on day 1, or daily filgrastim (10 microg/kg) for < or =7 days. Mean peak peripheral CD34+ cell counts increased with pegfilgrastim dose, but were significantly higher than filgrastim only at the 18 mg dose (10.17 vs 4.96 x 10(4)/ml; P=0.014). In the clinically relevant period of days 3-7, both 12 and 18 mg pegfilgrastim doses produced significantly higher peak CD34+ counts (8.18 and 9.96 vs 4.51 x 10(4)/ml for filgrastim; P=0.034 and 0.006). In cycle 1, patients received carboplatin/paclitaxel on day 1, followed from day 2 by pegfilgrastim 6-18 mg or daily filgrastim (5 microg/kg/day for < or =14 days) as per randomization in cycle 0. There were no significant differences in mean peak CD34+ count between pegfilgrastim and filgrastim, but there was an advantage for pegfilgrastim 18 mg in the relevant period of days 7-12 (3.14 vs 1.19 x 10(4)/ml; P=0.043). A single pegfilgrastim dose (> or =6 mg) could be substituted for daily filgrastim in cytokine-only peripheral CD34+ cell mobilization.

Raised serum urea predicts for early death in small cell lung cancer.

AIMS: Previous studies have defined prognostic factors predicting a favourable response to treatment and long-term survival in small cell lung cancer (SCLC) patients. Here we sought specific pre-treatment features predicting early death in SCLC. MATERIALS AND METHODS: An exploratory cohort of 62 patients with poor prognosis SCLC and a separate confirmatory independent cohort of 152 unselected SCLC patients were identified to determine risk factors for early death, defined as within 8 weeks of diagnosis. RESULTS: In an exploratory cohort of patients with poor prognosis SCLC, 46 received chemotherapy and 16 patients received no chemotherapy. Multivariate analysis of chemotherapy patients showed a raised serum urea to be predictive of early death - increasing the risk by 13-fold (odds ratio 13.3, 95% confidence interval=2.8-64). In a separate cohort of 152 unselected SCLC patients, 123 received chemotherapy and 29 did not. Logistic regression analysis of treated patients showed that performance status >2 (P=0.009), urea>upper limit of normal (P=0.01), neutrophil count >10 (P=0.024) and weight loss >10% (P=0.03) significantly contributed to the risk of early death. Of note, raised serum urea increased the risk of early death by 12-fold (odds ratio 11.8, 95% confidence interval=1.8-76.9). CONCLUSION: We have shown that pre-treatment raised serum urea is a significant predictor of early death. This readily available information will be useful for assessing SCLC patients at the bedside and discussing the risks of chemotherapy with them.

Follow up after Primary Treatment of Soft Tissue Sarcoma: A Survey of Current Practice in the United Kingdom.

Despite the clinical and financial implications, there is little evidence about how patients who have been treated for soft tissue sarcoma should be followed up. The purpose of this study was to determine current practice in the United Kingdom. 192 clinicians treating patients with soft tissue sarcoma were surveyed with a postal questionnaire enquiring about frequency and method of follow up and how patients would be followed up in each of 3 clinical scenarios: a patient with a trunk or extremity tumour at low risk of relapse; a patient with a trunk or extremity tumour at high risk of relapse; and a patient with a retroperitoneal or abdominal tumour. 155 (81%) clinicians responded. Clinic visits and X-rays were the most frequently used methods of follow up. Chest CT scans, local site imaging, and blood tests were used infrequently. The intensity and methods of follow up varied with each of the clinical scenarios. There was a seven-to-twenty fold variation in cost between the least and the most expensive regimes. Respondents were generally supportive of the development of the clinical trial in this area.

Production and upregulation of granulocyte chemotactic protein-2/CXCL6 by IL-1beta and hypoxia in small cell lung cancer.

Small cell lung cancer (SCLC) is characterised by early and widespread metastasis. However, SCLC cells have so far been found to produce low levels of known pro-angiogenic factors. We speculated that SCLC cells might produce alternative pro-angiogenic factors. Here, we report that a panel of SCLC cell lines constitutively secrete granulocyte chemotactic protein-2 (GCP-2)/CXCL6, a CXC ELR+ chemokine. In contrast, none of the three tested NSCLC cell lines secreted GCP-2. Production of GCP-2 in vivo was also confirmed in seven out of nine specimens with SCLC. We demonstrate that expression of GCP-2 is mediated by NF-kappaB as ALLN, an NF-kappaB pathway inhibitor, almost completely abolished GCP-2 production in SCLC cell lines. We also demonstrate that GCP-2 can be significantly upregulated by IL-1beta and hypoxia in SCLC cell lines. This result suggests a role for GCP-2 in promoting tumour progression in vivo under unfavourable conditions such as oxygen deprivation. As SCLC cells express both GCP-2 and its receptors CXCR1 and CXCR2, their biological significance in SCLC progression was further studied. We demonstrate that GCP-2 is an autocrine growth factor. Cell proliferation was significantly inhibited by anti-GCP-2 neutralising antibody in two high-GCP-2-producing cell lines. In addition, expression of the proliferation marker PCNA was upregulated by exogenous GCP-2 in two low-GCP-2-producing cell lines. Taken together, these results suggest an important role for GCP-2 as an autocrine mitogen in the growth and metastasis of SCLC.

Interleukin-8/CXCL8 is a growth factor for human lung cancer cells.

Interleukin-8/CXCL8 (IL-8) is a chemokine and angiogenic factor. Recently, IL-8 was identified as an autocrine growth factor in several human cancers. Here, we investigated the expression and function of IL-8 in lung cancer cells. The expressions of IL-8 and its receptors, CXCR1 and CXCR2, were examined in a panel of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) cell lines. Using reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay, we found that all NSCLC cell lines tested produced modest or high levels of IL-8 (up to 51 ng ml(-1) 10(6) cells(-1)). Expression of CXCR1 and CXCR2 was found by RT-PCR and flow cytometry in two out of three cell lines. In contrast, SCLC cell lines produced very low or undetectable levels of IL-8, but expressed CXCR1 and CXCR2. We next investigated whether IL-8 could act as an autocrine growth factor in two NSCLC cell lines (H460 and MOR/P) expressing both IL-8 and its receptors. We found that cell proliferation was attenuated by anti-IL-8 neutralising antibody to 71 and 76% in H460 and MOR/P, respectively (P<0.05). Exogenous IL-8 significantly stimulated cell proliferation in four SCLC cell lines tested in a dose-dependent fashion. Cell proliferation was increased by between 18% (P<0.05) and 37% (P<0.05). Stimulation of cell proliferation by IL-8 was also demonstrated by analysis of proliferating cell nuclear antigen expression and cell cycle in H69 cells. Furthermore, we investigated which receptor(s) mediated the mitogenic function of IL-8 in lung cancer cells. We found that cell proliferation was significantly reduced by anti-CXCR1 antibody but not by anti-CXCR2 antibody. In conclusion, IL-8 can act as an autocrine and/or paracrine growth factor for lung cancer cells, and the mitogenic function of IL-8 in lung cancer is mediated mainly by CXCR1 receptor.

A study of amsalog (CI-921) administered orally on a 5-day schedule, with bioavailability and pharmacokinetically guided dose escalation.

PURPOSE: Amsalog is a derivative of 9-aminoacridine. Phase I studies using intravenous (i.v.) amsalog have shown the dose-limiting toxicity (DLT) to be phlebitis and myelosuppression. Phase II studies using a variety of schedules have shown evidence of activity in patients with large-cell lung, breast, and head and neck cancers. Preclinical studies demonstrated that amsalog is active orally: a clinical study of the oral bioavailability of amsalog was therefore performed. METHODS: A group of 20 patients with refractory malignancies were treated. There were two phases of the study: a pharmacokinetic comparison of i.v. against oral amsalog, followed by a pharmacokinetically guided oral dose escalation study. In the first phase of the study, 11 patients were treated. Amsalog 50 mg/m2 was administered i.v., and 50 mg/m2 and 200 mg/m2 orally. In the second phase of the study, 9 patients were treated in three cohorts of three. On day 1 of a 5-day schedule, amsalog was administered i.v. at the maximum tolerated dose (MTD) of 200 mg/m2. Subsequent doses were given orally, starting at a dose of 200 mg/m2 per day, with intrapatient dose escalation of up to 100% for the second cycle. Doses were escalated further in subsequent cohorts, based on oral bioavailability and toxicity. RESULTS: Oral bioavailability of 50 mg/m2 amsalog was 34%. In the dose escalation phase, DLT was neutropenia; other toxicities included malaise and nausea. The MTD was 1600 mg/m2 per day for 5 days. The plasma AUC using 1600 mg/m2 by the oral route was higher than that achieved using 200 mg/m2 by the i.v. route. CONCLUSION: Amsalog can be tolerated orally on a 5-day schedule at doses up to 1600 mg/m2. The recommended dose for further evaluation is 800 mg/m2 daily for 5 days, repeated three weekly.

Use of RT-PCR to detect co-expression of neuropeptides and their receptors in lung cancer.

Small-cell lung cancer (SCLC) synthesises a wide range of neuropeptides and their corresponding receptors. Together, these can form autocrine growth loops. Non-small-cell lung cancer (NSCLC) does not generally share this neuroendocrine phenotype. In this study, we tested the hypothesis that multiple neuropeptides and their receptors are co-expressed in SCLC, constituting potential autocrine loops. Expression of mRNA for arginine vasopressin, gastrin, cholecystokinin, gastrin-releasing peptide, endothelin and neurotensin, together with their cognate receptors, was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) in a panel of human lung cancer cell lines. We have assessed those neuropeptides and neuropeptide receptors that could be used as potential early markers to detect lung cancer cells both as micrometastases in blood and within dysplasia in bronchial biopsies. We establish that although no cell line expressed all neuropeptides, co-expression of neuropeptides and their receptors is common in SCLC but not in NSCLC. We conclude that mRNA for the neuropeptides gastrin-releasing peptide and arginine vasopressin and the cholecystokinin receptor B were most SCLC-specific and RT-PCR for these markers could be used to distinguish between SCLC and NSCLC.

Lung cancer as the presenting feature of AIDS.

Several reports have suggested that there is an increased incidence of lung cancer amongst the HIV positive population. All cases of lung cancer reported in this group to date were in patients known previously to be HIV positive. We now report a case of AIDS presenting with small cell lung cancer. Unexpectedly severe pancytopenia and immunosuppression after combination chemotherapy revealed the underlying diagnosis. The prognosis in such cases is very poor, but it is important to establish the correct diagnosis in order for patients to make informed treatment decisions and to allow potentially life-saving treatment of their sexual partners.