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http://www.uniurb.it/it/portale/dip-biochimica/edocs/Relazioni.pdf

During the different phases of mycorrhizal fungi life cycle, several morphological, genetic and metabolic modifications are induced for both symbiotic partners. These changes are influenced by multiple environmental factors: light, gravity, oxygen, temperature, soil typology, nutrient availability, root exudates (that content sugars) and the presence of particular bacterial populations in the mycorrhizosphere. In the present study we focused on the influence of the host plant and of different nutritional substrates. An in vitro model has been set up, in which plant (Tilia americana) and fungus (Tuber borchii) were close one each other, but physically separated by a membrane, in order to perform a suppressive subtractive library able to find out genes differentially expressed in the pre-symbiotic phase (in the presence of the plant). The results obtained highlighted that in the presence of the plant the fungus shows a major expression of genes involved in hyphal growth, detoxification processes and general metabolism. Furthermore studies has been performed on T. borchii mycelia cultivated in different carbohydrates sources: morphological and molecular investigations highlighted that in the presence of glucose the fungus shows an implemented growth and a major expression of genes involved in hyphal growth, detoxification processes and general metabolism

The combination of carboplatin and paclitaxel given every three weeks is a tolerated and reasonably active regimen in advanced non-small cell lung cancer (NSCLC). This study was designed to evaluate the maximum tolerated dose (MTD) of a fixed dose of carboplatin with an area under the curve (AUC) of 6 and escalating doses of weekly paclitaxel with an initial dose of 50 mg/m2 with 10 mg/m2 increments at each level in untreated NSCLC patients (phase I study). The study continued with a phase II study. Thirty patients entered the phase I study. The MTD was: carboplatin AUC = 6 on days 1 and 28 plus paclitaxel 100 mg/m2 (1 hour) on days 1, 8,15, 28. The dose-limiting toxicity (DLT) was severe neutropenia and cardiological toxicity. Subsequently, 42 patients entered the phase II study with the same treatment schedule. The 2-drug combination was globally well tolerated. The overall response rate (RR) was 42% [CI 95%: 26.3-57.7], stable disease (SD) 29% and progression (PD) 29%. The median duration of response was 8.0 mos (range: 1.0-19.0). The median time to progression was 8.0 mos (range: 7.0-19.0) and the median survival was 14.0 months (range: 9.0-19.0). The association of carboplatin AUC = 6 and weekly paclitaxel 100 mg/m2 proved to be manageable, active and extremely safe even in elderly patients (one third of all patients in our cohort). The survival results were interesting: the median survival time was 14 months (9-19 months) and the 1- and 2-year survival was 59% and 16%, respectively.

Background/aim Regorafenib (REG) and trifluridine/tipiracil (FTD/TPI) have have been shown to improve overall survival in patients with refractory metastatic colorectal cancer. The aim of our study was to evaluate the efficacy and safety profiles of these agents administered in sequence in real world practice. Patients and methods Clinical data of patients treated beyond the 2°line with REG or FTD/TPI between January 2016 and August 2020, were retrospectively collected from eight institutes in the Lazio Region. Results We included 49 patients treated with both drug sequences. A total of 28 G3/G4 toxicity events (53.8%) were recorded in the FTD/TPI-to-REG sequence vs. 24 (46.1%) in the reverse sequence. Median overall survival for the patients included in the FTP/TPI-to-REG group was 20 months (95%CI=16.7-23.3) vs. 27 months in the reverse group (95%CI=17.8-36.2). The disease control rate was 45.0% for patients treated with the REG-to-FTD/TPI sequence vs. 24.1% in those treated with the FTD/TPI-to-REG sequence (p=0.18). Conclusion The sequence REG-to-FTD/TPI and vice versa can extend survival, whereas only REG-to-FTD/TPI stabilizes cancer growth.

Background: The evolution of therapeutic landscape of human epidermal growth factor receptor-2 (HER2)-positive breast cancer (BC) has led to an unprecedented outcome improvement, even if the optimal sequence strategy is still debated. To address this issue and to provide a picture of the advancement of anti-HER2 treatments, we performed a large, multicenter, retrospective study of HER2-positive BC patients. Methods: The observational PANHER study included 1,328 HER2-positive advanced BC patients treated with HER2 blocking agents since June 2000 throughout July 2020. Endpoints of efficacy were progression-free survival (PFS) and overall survival (OS). Results: Patients who received a first-line pertuzumab-based regimen showed better PFS ( p < 0.0001) and OS ( p = 0.004) than those receiving other treatments. Median PFS and mOS from second-line starting were 8 and 28 months, without significant differences among various regimens. Pertuzumab-pretreated patients showed a mPFS and a mOS from second-line starting not significantly affected by type of second line, that is, T-DM1 or lapatinib/capecitabine ( p = 0.80 and p = 0.45, respectively). Conversely, pertuzumab-naïve patients receiving second-line T-DM1 showed a significantly higher mPFS compared with that of patients treated with lapatinib/capecitabine ( p = 0.004). Median OS from metastatic disease diagnosis was higher in patients treated with trastuzumab-based first line followed by second-line T-DM1 in comparison to pertuzumab-based first-line and second-line T-DM1 ( p = 0.003), although these data might be partially influenced by more favorable prognostic characteristics of patients in the pre-pertuzumab era. No significant differences emerged when comparing patients treated with ‘old’ or ‘new’ drugs ( p = 0.43), even though differences in the length of the follow-up between the two cohorts should be taken into account. Conclusion: Our results confirmed a relevant impact of first-line pertuzumab-based treatment and showed lower efficacy of second-line T-DM1 in trastuzumab/pertuzumab pretreated, as compared with pertuzumab-naïve patients. Our findings may help delineate a more appropriate therapeutic strategy in HER2-positive metastatic BC. Prospective randomized trials addressing this topic are awaited.

The present work aimed to investigate whether exposure to static magnetic field (SMF) and extremely low frequency magnetic field (ELF-MF) can induce biomolecular changes on Tuber borchii hyphal growth. Tuber borchii mycelium was exposed for 1 h for 3 consecutive days to a SMF of 300 mT or an ELF-MF of 0.1 mT 50 Hz. Gene expression and biochemical analyses were performed. In mycelia exposed to ELF-MF, some genes involved in hyphal growth, investigated using quantitative real-time polymerase chain reaction, were upregulated, and the activity of many glycolytic enzymes was increased. On the contrary, no differences were observed in gene expression after exposure to SMF treatment, and only the activities of glucose 6-phosphate dehydrogenase and hexokinase increased. The data herein presented suggest that the electromagnetic field can act as an environmental factor in promoting hyphal growth and can be used for applicative purposes, such as the set up of new in vitro cultivation techniques.

The homocysteine synthase (tbhos) and putative sulfate transporter (tbsul1) genes have been characterized in order to understand the sulfate metabolism and regulation in the ectomycorrhizal fungus Tuber borchii. The analyses of tbsul1 and tbhos nucleotide and deduced amino acid sequences led to the identification of the typical domains shown in homologous proteins. Sulfate starvation condition upregulates both genes. The real-time PCR assay of tbsul1 revealed that gene expression was about threefold higher in mycelia grown under sulfate starvation for 2 days than in the mycelial control and in the same starvation condition, the sulfate uptake increased. Real-time PCR and enzymatic assays showed regulation of tbhos when sulfur sources were lacking, suggesting that a transcriptional regulation of this gene rather than a post-transcriptional one occurred. Furthermore, the tbsul1 and tbhos expression patterns were evaluated during the truffle life cycle, revealing an over-expression in the mature ascomata for both genes. In the ectomycorrhizal tissue, only tbhos was upregulated suggesting its substantial role in T. borchii cysteine synthesis. The regulation of tbsul1 and tbhos occurs primarily at the transcriptional level both during vegetative and fruiting phases and these genes could be directly involved in VOCs production.

During the life cycle of mycorrhizal fungi, morphological, genetic and metabolic modifications are induced in the fungus and its symbiotic partner. These changes are influenced by environmental factors: light, gravity, oxygen, temperature, soil type, nutrients, root exudates and the presence of particular bacterial and perhaps fungal and viral populations in the mycorrhizosphere. To determine whether different carbohydrates lead to cell-signalling events and morphofunctional changes in cultured Tuber borchii mycelia, the expression level of genes involved in morphological modifications was investigated using a macroarray technique and real-time RT-PCR. The morphological study showed an increased growth of Tuber mycelia in glucose, while the hyphae were thinner and less branched in sucrose and maltose. This was accompanied by an upregulation of the genes involved in the general cell metabolism, detoxification processes, hyphal growth and cytoskeleton organization. Since glucose is also present in root exudates, the increased expression of these genes might support the hypothesis that glucose can act as a signal for the fungus to indicate the presence of the plant, and to trigger the complex symbiotic process. These mechanisms can lead to morphological modifications, including increased branching of the root which is necessary for the fungus to establish the symbiosis.

Diversity of nitrogen-fixing bacteria and the nitrogen-fixation activity was investigated in Tuber magnatum, the most well-known prized species of Italian white truffle. Degenerate PCR primers were applied to amplify the nitrogenase gene nifH from T. magnatum ascomata at different stages of maturation. Putative amino acid sequences revealed mainly the presence of Alphaproteobacteria belonging to Bradyrhizobium spp. and expression of nifH genes from Bradyrhizobia was detected. The nitrogenase activity evaluated by acetylene reduction assay was 0.5–7.5 μmol C2H4 h−1 g−1, comparable with early nodules of legumes associated with specific nitrogen-fixing bacteria. This is the first demonstration of nitrogenase expression gene and activity within truffle.