Dye-conjugated complementary lipophilic nucleosides as useful probes to study association processes by fluorescence resonance energy transfer.

Modern supramolecular chemistry relies on the combination of diverse analytical techniques that can provide complementary information on complex self-assembly landscapes. Among them, resonance energy transfer, monitored by fluorescence emission spectroscopy, arises as a sensitive and convenient phenomenon to report binding intermolecular interactions. The use of molecular probes labelled with suitable complementary energy-transfer pairs can provide valuable information about the thermodynamics, kinetics and self-sorting characteristics of a particular self-assembled system. The objective of this work is to generate a set of nucleoside FRET probes that can be reliably employed to prove and analyse quantitatively H-bonding interactions between complementary Watson-Crick pairs. We first describe the preparation of a set of lipophilic nucleosides that are linked to a π-conjugated functional fragment. The bases include guanosine and 2-aminoadenosine as purine heterocycles, and cytidine and uridine as complementary pyrimidine bases. The π-conjugated moiety comprises either a short phenylene-ethynylene oligomer, a bithiophene, or a BODIPY dye. We then demonstrate that the last two chromophores constitute an energy donor-acceptor couple and that donor emission quenching can be related to the ratio of molecules bound to the complementary acceptor pair. Hence, fluorescence spectroscopy in combination with resonance energy transfer, is shown here to be a useful tool to study and quantify the association and self-sorting events between complementary and non-complementary nucleosides in apolar aromatic solvents, where the binding strength is considerably high, and sensitive techniques that employ low concentrations are demanded.

Bevacizumab plus preoperative chemotherapy in operable HER2 negative breast cancer: biomarkers and pathologic response

PURPOSE: The primary aim of this trial was to assess the rate of pathologic complete responses (pCR) of doxorubicin/cyclophosphamide (AC) followed by bevacizumab/docetaxel (BT), as neoadjuvant therapy for breast cancer (BC). Furthermore, the association between biomarkers and the pCR was explored. METHODS: Patients with HER-negative operable stage II-III BC ≥ 2 cm were enrolled. Four cycles of AC (A 60 mg/m(2) and C 600 mg/m(2), every 3 weeks) followed by 4 cycles of BT (B 15 mg/kg and T 75 mg/m(2), every 3 weeks), were planned. A core-biopsy was performed for biological markers assessment. RESULTS: Seventy-two women were included. Forty-three (63 %) patients were hormone receptor-positive. Sixty-four (89 %) completed the planned treatment, and 66 evaluable patients underwent surgery (92 %): a pCR was achieved in 16 of them (24, 95 % CI 15-36 %). pCR was significantly higher in tumors hormone receptor-negative, and in those with Angiotensin II type 1 receptor (AGTR1) protein overexpression. The overall clinical response rate was 86 % (95 % CI 76-93 %), including 42 complete responses. No unexpected toxicities or treatment-related deaths were observed. CONCLUSION: This regimen showed a remarkable clinical and pathological activity: the suggested relation between pCR and AGTR1 overexpression should be confirmed in larger trials (AU)

Bevacizumab plus preoperative chemotherapy in operable HER2 negative breast cancer: biomarkers and pathologic response.

PURPOSE: The primary aim of this trial was to assess the rate of pathologic complete responses (pCR) of doxorubicin/cyclophosphamide (AC) followed by bevacizumab/docetaxel (BT), as neoadjuvant therapy for breast cancer (BC). Furthermore, the association between biomarkers and the pCR was explored. METHODS: Patients with HER-negative operable stage II-III BC ≥ 2 cm were enrolled. Four cycles of AC (A 60 mg/m(2) and C 600 mg/m(2), every 3 weeks) followed by 4 cycles of BT (B 15 mg/kg and T 75 mg/m(2), every 3 weeks), were planned. A core-biopsy was performed for biological markers assessment. RESULTS: Seventy-two women were included. Forty-three (63 %) patients were hormone receptor-positive. Sixty-four (89 %) completed the planned treatment, and 66 evaluable patients underwent surgery (92 %): a pCR was achieved in 16 of them (24, 95 % CI 15-36 %). pCR was significantly higher in tumors hormone receptor-negative, and in those with Angiotensin II type 1 receptor (AGTR1) protein overexpression. The overall clinical response rate was 86 % (95 % CI 76-93 %), including 42 complete responses. No unexpected toxicities or treatment-related deaths were observed. CONCLUSION: This regimen showed a remarkable clinical and pathological activity: the suggested relation between pCR and AGTR1 overexpression should be confirmed in larger trials.

Pilot study on workload estimate in breast cancer, lung cancer and colorectal cancer in a Medical Oncology Service at Valme hospital

New advances in the diagnosis and treatment of cancer and the increased incidence and prevalence of this disease have led to an increase in the number and duration of visits in Medical Oncology in the last few years. Based on the functions of a medical oncologist and the time recommended for each work activity established by the Spanish Society of Medical Oncology (SEOM), we carried out a pilot study on the three most frequent neoplasias in our country [breast cancer (BC), lung cancer (LC) and colorectal cancer (CRC)], in order to determine the real time each patient requires from a physician and thus establish a recommendation on the number of medical oncologists necessary. Using the actual itinerary of the first 20 patients of 2009 in each of the three neoplasias seen at the Medical Oncology Service of the Virgen de Valme University Hospital, we measured the number of visits, the antineoplastic treatments received, the number of hospital admissions and average length of stay. During the years following the study, these data were estimated based on the natural history of each neoplasia. During the first year, the average time spent by the medical oncologist was 235, 390 and 265 min on each outpatient with BC, LC and CRC, respectively. In hospitalisation, the average oncologist/patient minutes were 40, 360 and 118 for BC, LC and CRC, respectively. Finally, the time spent on each visit or day of hospitalisation was that recommended by the SEOM, achieving an ultimate ratio of 1 oncologist for every 83 first visits (AU)

Classical markers like ER and ki-67, but also survivin and pERK, could be involved in the pathological response to gemcitabine, adriamycin and paclitaxel (GAT) in locally advanced breast cancer patients: results from the GEICAM/2002-01 phase II study

INTRODUCTION: The identification and validation of biomarkers of chemotherapy sensitivity is critical in order to individualise therapy in breast cancer. We evaluated pathological complete response (pCR) to GAT, and its correlation with tumour biomarkers before and after neoadjuvant chemotherapy. MATERIALS AND METHODS: Stage III (and stage II with T≥5 cm) breast cancer patients were included. Treatment consisted of adriamycin (40 mg/m(2)) day 1, and paclitaxel (150 mg/ m(2)) followed by gemcitabine (2000 mg/m(2)) day 2, every 14 days for six cycles. Tissue from pre-treatment biopsy and surgery was evaluated for biologic markers by immunohistochemistry. Two XPD single nucleotide polymorphisms (SNP) were also analysed. RESULTS: Forty-six patients entered the trial. Median age was 49.5 years (range 31-72); 25 patients (54%) were pre-menopausal; 12 (26%) were ER-PgR-negative; pCR was observed in 17% (95% CI: 6.4-28.4) of patients. Significant differences in marker expression (mean±SD) in correlation to pathological response were only found in Ki- 67. After treatment, tumours showed lower Ki-67-, surviving- and pERK-positive cells. No correlation between XPD polymorphisms and pCR was found. The overall response rate was 89% (95% CI: 80.1-98.1). Fifteen patients (33%) underwent breast-conserving surgery. The most frequent grade 3 or 4 toxicities were neutropenia (with one febrile neutropenia) and asthenia. CONCLUSION: These results show an effective regimen with acceptable tolerability. Our data suggest that not only classical markers (ER, Ki-67), but also survivin and pERK could be involved in the response to GAT, which may contribute to therapy individualisation in future study designs (AU)

Biweekly vinorelbine and tegafur/uracil in patients with metastatic breast cancer previously treated with anthracyclines and taxanes: GEICAM 2000-02 phase II study

INTRODUCTION: To assess the efficacy and safety profile of biweekly vinorelbine and tegafur/uracil (UFT) as treatment in patients with metastatic breast cancer previously treated with anthracyclines and taxanes. PATIENTS AND METHODS: Patients with histologically confirmed breast cancer, measurable disease, no more than one prior chemotherapy regimen for metastatic disease, an Eastern Cooperative Oncology Group (ECOG) performance status ≤2, and adequate bone marrow, renal and liver function were eligible. Patients received vinorelbine (30 mg/m(2) on day 1) and UFT (250 mg/m(2) daily) every two weeks for 12 cycles unless progression or unacceptable toxicity was observed. RESULTS: Thirty-seven patients were included and received 311 cycles of chemotherapy. Efficacy and toxicity analyses were carried out on an intention-to-treat basis. The overall response rate was 35% (95% CI: 20-53). With a median follow-up of 18.6 months (95% CI: 1.0-74.3), the median time to progression was 7.0 months (96% CI: 5.2-8.9) and the median overall survival was 19.4 months (95% CI: 11.1-27.8). The most common severe toxicities were neutropenia (38% of patients) and asthenia (11% of patients). CONCLUSION: The combination of biweekly vinorelbine and UFT in patients with metastatic breast cancer pretreated with anthracyclines and taxanes is a well tolerated and effective regimen. AEMPS Trial Registration No.: 00-0534 (AU)

Molecular basis of colorrectal cancer: towards an individualized management?

Colorectal cancer (CRC) has become a highly relevant condition nowadays. In this respect, advances in the understanding of its molecular basis are key for an adequate management. From the time when the adenoma-carcinoma sequence was formulated as a carcinogenesis model to this day, when -among other things- three major carcinogenic pathways have been identified, the CRC concept has evolved from that of a single disease to the notion that each CRC is a differentiated condition in itself. The suppressor or chromosome instability pathway, the mutator or microsatellite instability pathway, and the methylator or CpG island methylation pathway allow various phenotypes to be identified within CRC. Similarly, the presence of different changes in certain genes confers several behaviors on CRC from both the prognostic and responsive standpoints to specific therapies. However, this apparent complexity does help develop the clinical management of this disease through the identification of novel, more specific therapy targets, and also markers for various behaviors within the condition, which will most likely lead us to an individualized management for these patients.

Molecular basis of colorectal cancer: towards an individualized management?

Colorectal cancer (CRC) has become a highly relevant condition nowadays. In this respect, advances in the understanding of its molecular basis are key for an adequate management. From the time when the adenoma-carcinoma sequence was formulated as a carcinogenesis model to this day, when, among other things, three major carcinogenic pathways have been identified, the CRC concept has evolved from that of a single disease to the notion that each CRC is a differentiated condition in itself. The suppressor or chromosome instability pathway, the mutator or microsatellite instability pathway, and the methylator or CpG island methylation pathway allow various phenotypes to be identified within CRC. Similarly, the presence of different changes in certain genes confers several behaviors on CRC from both the prognostic and responsive standpoints to specific therapies. However, this apparent complexity does help develop the clinical management of this disease through the identification of novel, more specific therapy targets, and also markers for various behaviors within the condition, which will most likely lead us to an individualized management for these patients(AU)

Surgical management of hereditary colorectal cancer: surgery based on molecular analysis and family history.

The importance of colorectal cancer (CRC) is increasing. A proportion show a hereditary component, as in Lynch syndrome and Familial Adenomatous Polyposis, and a recently defined entity as well, namely, Familial Colorectal Cancer type X. The high probability to develop CRC in these groups may, at the time of recognition, change surgical management, including its timing or even the surgical technique. In some cases prophylactic surgery can play an important role. The possibility of using tools that allow recognition of the aforementioned syndromes, including microsatellite instability, immunohistochemistry for DNA mismatch repair system proteins, and especially their mutations, is on the basis of therapeutic strategies that differ from those employed in sporadic CRC cases.

Surgical management of hereditary colorectal cancer: surgery based on molecular analysis and family history

The importance of colorectal cancer (CRC) is increasing. Aproportion show a hereditary component, as in Lynch syndromeand Familial Adenomatous Polyposis, and a recently defined entityas well, namely, Familial Colorectal Cancer type X. The highprobability to develop CRC in these groups may, at the time ofrecognition, change surgical management, including its timing oreven the surgical technique. In some cases prophylactic surgerycan play an important role. The possibility of using tools that allowrecognition of the aforementioned syndromes, including microsatelliteinstability, immunohistochemistry for DNA mismatchrepair system proteins, and especially their mutations, is on thebasis of therapeutic strategies that differ from those employed insporadic CRC cases(AU)

A multicentre phase II study to evaluate sequential docetaxel followed by capecitabine treatment in anthracycline-pretreated HER-2-negative patients with metastatic breast cancer

INTRODUCTION: Treatment of HER-2-negative metastatic breast cancer (MBC) patients after anthracycline exposure is controversial. Docetaxel/capecitabine is a promising regimen, but the administration schedule is not well established. MATERIALS AND METHODS: Treatment included 3 cycles of docetaxel 100 mg/m2 day 1 every 21 days followed by 3 cycles of capecitabine 1250 mg/m2/12 h days 1-14. Patients not progressing were maintained with capecitabine 900 mg/m2/12 h on days 1-14 every 21 days until progression or unacceptable toxicity. RESULTS: Fifty-three anthracycline-pretreated patients were enrolled: median age 54 years, ECOG grade 0-1 86.7%. Most of the women received adjuvant chemotherapy (81%) and 5 patients (9%) had had prior metastatic chemotherapy treatment. Median time from anthracycline exposure was 29 months. ORR (intent-to-treatment analysis) after the sequential therapy was 51% (CI 95% 37-65) with 15% (CI 95% 7-28) of patients reaching complete responses. Median time to progression was 8.2 (CI 95% 7.1-10.7) months, with 61.9% (CI 95% 45.6-76.4) of the patients free of disease after 6 months. Median overall survival was not reached after a median follow-up of 10.4 months, and 75% of the patients were alive after 14.3 months. Survival rate after 12 months was 81.1% (CI 95% 68.0-90.6). The most frequent NCI grade 3-4 toxicities were hair loss (28.3%), asthenia (15.1%), stomatitis (11.32%) and nausea (11.32%). Severe hand-foot syndrome rate was 7.5%. CONCLUSIONS: Sequential docetaxel-capecitabine is feasible, effective and well tolerated in first-line MBC treatment. Evaluation of this schedule in randomised studies is warranted (AU)

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Global responses of terrestrial productivity to contemporary climatic oscillations.

The terrestrial biosphere is subjected to a wide range of natural climatic oscillations. Best known is the El Niño-southern oscillation (ENSO) that exerts globally extensive impacts on crops and natural vegetation. A 50-year time series of ENSO events has been analysed to determine those geographical areas that are reliably impacted by ENSO events. Most areas are impacted by changes in precipitation; however, the Pacific Northwest is warmed by El Niño events. Vegetation gross primary production (GPP) has been simulated for these areas, and tests well against independent satellite observations of the normalized difference vegetation index. Analyses of selected geographical areas indicate that changes in GPP often lead to significant changes in ecosystem structure and dynamics. The Pacific decadal oscillation (PDO) is another climatic oscillation that originates from the Pacific and exerts global impacts that are rather similar to ENSO events. However, the longer period of the PDO provided two phases in the time series with a cool phase from 1951 to 1976 and a warm phase from 1977 to 2002. It was notable that the cool phase of the PDO acted additively with cool ENSO phases to exacerbate drought in the earlier period for the southwest USA. By contrast in India, the cool phase of the PDO appears to reduce the negative impacts of warm ENSO events on crop production.

Phase-II study of weekly schedule of trastuzumab, paclitaxel, and carboplatin followed by a week off every 28 days for HER2+ metastatic breast cancer.

BACKGROUND: Addition of carboplatin (C) to trastuzumab (T) and paclitaxel (P) improves the efficacy in HER2+ metastatic breast cancer (MBC). The aim of this phase-II study was to evaluate the efficacy and safety of this combination given weekly (3x) followed by a week off. The primary endpoint was: objective response rate (ORR), and secondary endpoints were: time to progression (TTP), overall survival (OS), and toxicity profile. METHODS: HER2+ MBC patients were included in the study. Treatment was as follows: T (loading dose:4 mg/kg per week and 2 mg/kg per day thereafter), P (80 mg/m(2)) and C (AUC 2) given weekly 3x, followed by 1 week off until disease progression or unacceptable toxicity. RESULTS: Forty-one patients (pts) were enrolled-median age: 54.5 years (range 29-75); 87.8% PS 0 or 1; 39 (97.5%) had received prior adjuvant or neoadjuvant treatment; 11 (27%) had received one prior CT line for metastatic disease; disease sites: liver (40%), bone (32.5%), lymph nodes (32.5%) and lung (20%); 19 (47.5%) had > or =2 lesions and 97.5% had measurable disease. A total of 37 pts were evaluated for response: 11(26.8%) CR; 12 (29.3%) PR; 9 (22%) SD; 5 (12.2%) PD and 4 NE, resulting in an ORR of 56.1% (95% CI 39.7-71.5%) and tumor growth control rate (RR + SD) of 78% (95% CI 62.4-89.4%). With a median follow up of 39.4 months, 26 (70.3%) patients have progressed. The median time to progression was 12.3 months (95% CI 8.2-15.5). At the time of this report, ten patients have died. Forty patients received 202 cycles (median five cycles). Grades 3-4 toxicities/pts: 3 (7.5%) anemia, 2 (5%) leucopenia, 10 (25%) neutropenia, 1 (2.5%) febrile neutropenia,1 (2.5%) thrombopenia, 2 (5%) asthenia, 2 (5%) diarrhea, 3 (7.5%) nausea, 2 (5%) vomiting, and 3 (7.5%) mucositis. CONCLUSIONS: The schedule showed an interesting activity, taking into account that 27% of patients had received previous treatment for MBC. One week of rest may benefit not only the patient but may also improve tolerability and efficacy of the combination.

Docetaxel and mitomycin as second-line treatment in advanced non-small cell lung cancer.

PURPOSE: To evaluate the feasibility, toxicity and efficacy of the combination of docetaxel and mitomycin C as second-line chemotherapy in patients with advanced non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Thirty-eight patients with histologically confirmed, locally advanced or metastatic NSCLC were included in this phase II trial. All patients had been previously treated with a platinum-based regimen. Treatment consisted of docetaxel (75 mg/m2) followed by mitomycin C (8 mg/m2) on day 1, every 21 days. Patients received a minimum of three courses unless progressive disease was detected. RESULTS: A total of 190 courses of docetaxel-mitomycin C were administered (median five courses per patient). This combination was well tolerated with grade 3-4 toxicity experienced with the following frequency: neutropenia in five patients (13%), fatigue in four (11%), anaemia, thrombocytopenia, nausea/vomiting and peripheral neuropathy in one each (3%). Three of 38 patients had a partial response (8%, 95% confidence interval 2.6-21.6%), 14 patients (37%) experienced stabilization of disease and 21 (55%) had disease progression. Median time to progression was 3.6 months. Overall median survival was 10.4 months, with the 1-year actuarial survival rate being 35%. CONCLUSIONS: The addition of mitomycin C to docetaxel as second-line therapy in NSCLC is well tolerated but does not seem to improve the response rate.

Varón de 25 años con fiebre, adenopatías y lesiones cutáneas / 25 year old male with fever, abnormal lymph nodes and skin lesions

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Fixed dose-rate infusion of gemcitabine in combination with cisplatin and UFT in advanced carcinoma of the pancreas.

BACKGROUND: Gemcitabine is currently considered the standard treatment for advanced pancreatic cancer (APC). Cisplatin and a fluoropyrimidine have some activity in the treatment of this cancer. The aim of this trial is to evaluate the efficacy and toxicity of a fixed dose-rate infusion of gemcitabine associated with cisplatin and UFT in patients with APC. PATIENTS AND METHODS: Forty-six chemotherapy-naïve patients with APC that was either unresectable or metastatic were included in this phase II study. All of them had Karnofsky performance status > or =50 and unidimensionally measurable disease. Treatment consisted of gemcitabine 1,200 mg/m2 given as a 120-min infusion weekly for three consecutive weeks, cisplatin 50 mg/m2 on day 1 and oral UFT 400 mg/m2/day (in two to three daily doses) on days 1 to 21; cycles of treatment were given every 28 days. RESULTS: A total of 208 cycles of chemotherapy were given with a median of 4 per patient. Fourteen patients (30%) achieved partial responses (95% CI 19-48%) and 17 (37%) had stable disease. The median time to progression was 5 months, and the median overall survival 9 months. Nineteen patients (49%; 95% CI 32-64%) had a clinical benefit response. Grade 3-4 WHO toxicities were as follows: neutropaenia in 26 patients (57%), with 5 cases of febrile neutropaenia (11%), thrombocytopaenia in 15 (33%), anaemia in six (13%), diarrhoea in 5 (11%), asthenia in 2 (4%) and mucositis in 1 (2%). Seven patients required hospitalisation for treatment-related complications. CONCLUSION: A fixed dose-rate infusion of gemcitabine associated with cisplatin and UFT is active in patients with APC, though at the cost of considerable toxicity.

Constraining the Sheffield dynamic global vegetation model using stream-flow measurements in the United Kingdom.

The biospheric water and carbon cycles are intimately coupled, so simulating carbon fluxes by vegetation also requires modelling of the water fluxes, with each component influencing the other. Observations of river streamflow integrate information at the catchment scale and are widely available over a long period; they therefore provide an important source of information for validating or calibrating vegetation models. In this paper, we analyse the performance of the Sheffield dynamic global vegetation model (SDGVM) for predicting river streamflow and quantifying how this information helps to constrain carbon flux predictions. The SDGVM is run for 29 large catchments in the United Kingdom. Annual streamflow estimates are compared with long time-series observations. In 23 out of the 29 catchments, the bias between model and observations is less than 50 mm, equivalent to less than 10% of precipitation. In the remaining catchments, larger errors are because of combinations of unpredictable causes, in particular various human activities and measurement issues and, in two cases, unidentified causes. In one of the catchments, we assess to what extent a knowledge of annual streamflow can constrain model parameters and in turn constrain estimates of gross primary production (GPP). For this purpose, we assume the model parameters are uncertain and constrain them by the streamflow observations using the generalized likelihood uncertainty estimation method. Comparing the probability density function of GPP with and without constraint shows that streamflow effectively constrains GPP, mainly by setting a low probability to GPP values below about 1100 g C-1 m2 yr-1 . In other words, streamflow observations allow the rejection of low values of GPP, so that the potential range of possible GPP values is almost halved.

Global climate and the distribution of plant biomes.

Biomes are areas of vegetation that are characterized by the same life-form. Traditional definitions of biomes have also included either geographical or climatic descriptors. This approach describes a wide range of biomes that can be correlated with characteristic climatic conditions, or climatic envelopes. The application of remote sensing technology to the frequent observation of biomes has led to a move away from the often subjective definition of biomes to one that is objective. Carefully characterized observations of life-form, by satellite, have been used to reconsider biome classification and their climatic envelopes. Five major tree biomes can be recognized by satellites based on leaf longevity and morphology: needleleaf evergreen, broadleaf evergreen, needleleaf deciduous, broadleaf cold deciduous and broadleaf drought deciduous. Observations indicate that broadleaf drought deciduous vegetation grades substantially into broadleaf evergreen vegetation. The needleleaf deciduous biome occurs in the world's coldest climates, where summer drought and therefore a drought deciduous biome are absent. Traditional biome definitions are quite static, implying no change in their life-form composition with time, within their particular climatic envelopes. However, this is not the case where there has been global ingress of grasslands and croplands into forested vegetation. The global spread of grasses, a new super-biome, was probably initiated 30-45 Myr ago by an increase in global aridity, and was driven by the natural spread of the disturbances of fire and animal grazing. These disturbances have been further extended over the Holocene era by human activities that have increased the land areas available for domestic animal grazing and for growing crops. The current situation is that grasses now occur in most, if not all biomes, and in many areas they dominate and define the biome. Croplands are also increasing, defining a new and relatively recent component to the grassland super-biome. In the case of both grassland and croplands, various forms of disturbance, particularly frequent disturbance, lead to continued range extensions of the biomes.