Determinants Affecting the Clinical Implementation of a Molecularly Informed Molecular Tumor Board Recommendation: Experience from a Tertiary Cancer Center.

Molecular Tumor Boards (MTBs) converge state-of-the-art next-generation sequencing (NGS) methods with the expertise of an interdisciplinary team consisting of clinicians, pathologists, human geneticists, and molecular biologists to provide molecularly informed guidance in clinical decision making to the treating physician. In the present study, we particularly focused on elucidating the factors impacting on the clinical translation of MTB recommendations, utilizing data generated from gene panel mediated comprehensive genomic profiling (CGP) of 554 patients at the MTB of the Comprehensive Cancer Center Erlangen, Germany, during the years 2016 to 2020. A subgroup analysis of cases with available follow-up data (n = 332) revealed 139 cases with a molecularly informed MTB recommendation, which was successfully implemented in the clinic in 44 (31.7%) of these cases. Here, the molecularly matched treatment was applied in 45.4% (n = 20/44) of cases for ≥6 months and in 25% (n = 11/44) of cases for 12 months or longer (median time to treatment failure, TTF: 5 months, min: 1 month, max: 38 months, ongoing at data cut-off). In general, recommendations were preferentially implemented in the clinic when of high (i.e., tier 1) clinical evidence level. In particular, this was the case for MTB recommendations suggesting the application of PARP, PIK3CA, and IDH1/2 inhibitors. The main reason for non-compliance to the MTB recommendation was either the application of non-matched treatment modalities (n = 30)/stable disease (n = 7), or deteriorating patient condition (n = 22)/death of patient (n = 9). In summary, this study provides an insight into the factors affecting the clinical implementation of molecularly informed MTB recommendations, and careful considerations of these factors may guide future processes of clinical decision making.

A Possible Distinct Molecular Subtype (Quintuple-Wildtype) of Metastatic Colorectal Cancer in First-Line Anti-EGFR Therapy with Cetuximab Plus FOLFIRI - Palliative Precision Therapy and a Multidisciplinary Treatment Approach: Interim Analysis of the IVOPAK II Trial with Early Results.

OBJECTIVE: The study aimed to prospectively evaluate a new molecular biomarker panel (KRAS, NRAS, BRAF, PIK3CA, and ERBB2) for palliative first-line treatment of colorectal cancer (CRC), including a multidisciplinary treatment approach. The rate of secondary metastasis resections was assessed. PATIENTS AND METHODS: A total of 40 patients with definitively nonresectable metastatic CRC were enrolled from 10 centers before the interim analysis (June 2019) of the IVOPAK II trial (Interdisciplinary Care with Quality Control in Palliative Treatment of Colorectal Cancer). After determination of 5 molecular biomarkers in the tumor (KRAS, exons 2-4; NRAS, exons 2-4; BRAF V600E; PIK3CA; and ERBB2), patients in the IVOPAK II study received FOLFIRI plus cetuximab for all-RAS/quintuple-wildtype disease and FOLFIRI plus bevacizumab in the case of RAS mutations. The current article presents the early description of the clinical outcome of the interim analysis of IVOPAK II comparing the all-RAS/quintuple-wildtype and RAS-mutations populations, including a multidisciplinary-treated case report of a quintuple-wildtype patient. RESULTS: The quintuple-wildtype population treated with FOLFIRI plus cetuximab in first-line exhibited a significantly higher response rate and enhanced early tumor shrinkage in the interim analysis than the RAS-mutations population, as well as a high rate of secondary metastatic resections. CONCLUSION: Initial results of this new biomarker panel (quintuple-wildtype) are promising for anti-EGFR therapy with cetuximab plus doublet chemotherapy (FOLFIRI) in first-line treatment of metastatic CRC. These results warrant confirmation with higher case numbers in the IVOPAK II trial.

The Randomized AMBORA Trial: Impact of Pharmacological/Pharmaceutical Care on Medication Safety and Patient-Reported Outcomes During Treatment With New Oral Anticancer Agents.

PURPOSE: Oral anticancer drugs (eg, kinase inhibitors) play an important role in cancer therapy. However, considerable challenges regarding medication safety of oral anticancer drugs have been reported. Randomized, controlled, multicenter studies on the impact of intensified clinical pharmacological/pharmaceutical care on patient safety and patient treatment perception are lacking. METHODS: Patients were eligible for the randomized, multicenter AMBORA study, if they were newly started on any of the oral anticancer drugs approved in 2001 or later without restriction to certain tumor entities. Patients were randomly assigned to receive either standard of care (control group) or an additional, intensified clinical pharmacological/pharmaceutical care, which included medication management and structured patient counseling, over a period of 12 weeks (intervention group). Primary end points were the number of antitumor drug-related problems (ie, side effects and unresolved medication errors) and patient treatment satisfaction with the oral anticancer therapy after 12 weeks measured with the Treatment Satisfaction Questionnaire for Medication, category convenience. RESULTS: Two hundred two patients were included. Antitumor drug-related problems were significantly lower in the intervention compared with the control group (3.85 v 5.81 [mean], P < .001). Patient treatment satisfaction was higher in the intervention group (Treatment Satisfaction Questionnaire for Medication, convenience; 91.6 v 74.4 [mean], P < .001). The hazard ratio for the combined end point of severe side effects (Common Terminology Criteria for Adverse Events ≥ 3), treatment discontinuation, unscheduled hospital admission, and death was 0.48 (95% CI, 0.32 to 0.71, P < .001) in favor of the intervention group. CONCLUSION: Treatment with oral anticancer drugs is associated with a broad range of medication errors and side effects. An intensified clinical pharmacological/pharmaceutical care has considerable, positive effects on the number of medication errors, patient treatment perception, and severe side effects.

Weekly High-dose 5-Fluorouracil as 24-hour Infusion Combined with Sodium Folinic Acid (AIO regimen) Plus Irinotecan in Second-line and Sequential Therapy of Metastatic Colorectal Cancer (CRC).

BACKGROUND/AIM: The aim of this work was to evaluate the efficacy and safety of second-line treatment with weekly high-dose 5-fluorouracil (5-FU) as a 24-hour infusion (24-h inf.) combined with sodium folinic acid (FA) (AIO-regimen) plus irinotecan (Iri.) after pretreatment with AIO-regimen plus oxaliplatin (L-OHP). PATIENTS AND METHODS: Patients with non-resectable distant CRC metastases were enrolled in a prospective phase II study for palliative second-line treatment after previous progression of first-line treatment in accordance with the AIO-regimen plus oxaliplatin. On an outpatient basis, the patients received a treatment regimen comprising of weekly 80 mg/m2 irinotecan in the form of a 1-hour i.v. infusion and 2,000 mg/m2 5-FU combined with 500 mg/m2 sodium folinic acid administered as a 24-h infusion i.v. once weekly. RESULTS: During second-line treatment, a total of 59 patients received 520 chemotherapy applications. As the main higher-grade symptom of toxicity, diarrhea (NCI-CTC-toxicity grade 3) presented in 8 patients (13.6%, 95%CI=5.1-23.7), followed by leukocytopenia (CTC grade 3) in 3 patients (5.1%, 95%CI=0-11.9), followed by thrombocytopenia (CTC grade 3) in 1 patient (1.7%, 95%CI=0-5.1). Fifty-nine patients were evaluable for treatment response. The remission data can be summarized as follows: complete remission (CR); n=0; partial remission (PR); n=6 (10%; 95%CI=3.4-18.6); stable disease (SD); n=31 (53%; 95%CI=39.0-64.4); progressive disease (PD); n=19 (33%; 95%CI=20.3-44.1). The median progression-free survival (PFS) rate (n=59) was 4.2 months (range=3.8-5.8 months). The median survival time counted from the start of second-line treatment (n=59) 14.2 months (range 8.2-17.3 months) and the median survival time counted from the start of first-line therapy (n=59) 25 months (range 19-27 months). CONCLUSION: Palliative second-line treatment according to the AIO regimen plus irinotecan offers both a favourable toxicity profile and promising efficacy in second-line and palliative sequential therapy.

Methylfolate Trap Promotes Bacterial Thymineless Death by Sulfa Drugs.

The methylfolate trap, a metabolic blockage associated with anemia, neural tube defects, Alzheimer's dementia, cardiovascular diseases, and cancer, was discovered in the 1960s, linking the metabolism of folate, vitamin B12, methionine and homocysteine. However, the existence or physiological significance of this phenomenon has been unknown in bacteria, which synthesize folate de novo. Here we identify the methylfolate trap as a novel determinant of the bacterial intrinsic death by sulfonamides, antibiotics that block de novo folate synthesis. Genetic mutagenesis, chemical complementation, and metabolomic profiling revealed trap-mediated metabolic imbalances, which induced thymineless death, a phenomenon in which rapidly growing cells succumb to thymine starvation. Restriction of B12 bioavailability, required for preventing trap formation, using an "antivitamin B12" molecule, sensitized intracellular bacteria to sulfonamides. Since boosting the bactericidal activity of sulfonamides through methylfolate trap induction can be achieved in Gram-negative bacteria and mycobacteria, it represents a novel strategy to render these pathogens more susceptible to existing sulfonamides.

Successful Multidisciplinary Treatment with Secondary Metastatic Liver Resection after Downsizing by Palliative Second-Line Treatment of Colorectal Cancer: A Curative Option.

INTRODUCTION: The prognostic outcome following progression after palliative first-line treatment for patients suffering from metastatic colorectal adenocarcinoma is generally poor. Long-term relapse-free survival with palliative second-line treatment may be achieved in only a limited number of individual cases. CASE REPORT: A 37-year-old patient presented with bilobar liver metastases of colon cancer confirmed by histology with wild-type K-RAS (exon 2). Due to progressive disease after eight cycles of first-line therapy with FOLFIRI plus cetuximab, second-line chemotherapy with modified FOLFOX4 (mFOLFOX4) plus bevacizumab was initiated. During four cycles of mFOLFOX4 plus bevacizumab (2 months), no higher-grade toxicity occurred. Liver MRI with contrast medium revealed downsizing of the segment II/III metastases, as well as regressive, small, faint, hardly definable lesions in segments VI and IVb. The interdisciplinary tumor board of the University of Erlangen thus decided to perform resection of the liver metastases. Segments II and III were resected, and the liver metastases in segments IVa and VI were excised (R0). Histopathology confirmed three of the R0-resected metastases to be completely necrotic, with residual scarring. As perioperative therapy, four additional cycles of mFOLFOX4 plus bevacizumab were administered postoperatively. No higher-grade toxicity was observed. Three years after the initial diagnosis, the patient is relapse free, professionally fully reintegrated, and has an excellent performance status. CONCLUSION: Patients suffering from metastatic colorectal cancer may benefit from multidisciplinary treatment with secondary metastatic liver resection after downsizing by palliative second-line treatment. In individual cases, patients may even have a curative treatment option, provided that close interdisciplinary collaboration exists.

Chemical Genetic Analysis and Functional Characterization of Staphylococcal Wall Teichoic Acid 2-Epimerases Reveals Unconventional Antibiotic Drug Targets.

Here we describe a chemical biology strategy performed in Staphylococcus aureus and Staphylococcus epidermidis to identify MnaA, a 2-epimerase that we demonstrate interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. Genetic inactivation of mnaA results in complete loss of WTA and dramatic in vitro ß-lactam hypersensitivity in methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE). Likewise, the ß-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSA and MRSE infection. Interestingly, whereas MnaA serves as the sole 2-epimerase required for WTA biosynthesis in S. epidermidis, MnaA and Cap5P provide compensatory WTA functional roles in S. aureus. We also demonstrate that MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSA and MRSE. We further determine the 1.9Å crystal structure of S. aureus MnaA and identify critical residues for enzymatic dimerization, stability, and substrate binding. Finally, the natural product antibiotic tunicamycin is shown to physically bind MnaA and Cap5P and inhibit 2-epimerase activity, demonstrating that it inhibits a previously unanticipated step in WTA biosynthesis. In summary, MnaA serves as a new Staphylococcal antibiotic target with cognate inhibitors predicted to possess dual therapeutic benefit: as combination agents to restore ß-lactam efficacy against MRSA and MRSE and as non-bioactive prophylactic agents to prevent Staphylococcal biofilm formation.

Glucanocellulosic ethanol: the undiscovered biofuel potential in energy crops and marine biomass.

Converting biomass to biofuels is a key strategy in substituting fossil fuels to mitigate climate change. Conventional strategies to convert lignocellulosic biomass to ethanol address the fermentation of cellulose-derived glucose. Here we used super-resolution fluorescence microscopy to uncover the nanoscale structure of cell walls in the energy crops maize and Miscanthus where the typical polymer cellulose forms an unconventional layered architecture with the atypical (1, 3)-ß-glucan polymer callose. This raised the question about an unused potential of (1, 3)-ß-glucan in the fermentation of lignocellulosic biomass. Engineering biomass conversion for optimized (1, 3)-ß-glucan utilization, we increased the ethanol yield from both energy crops. The generation of transgenic Miscanthus lines with an elevated (1, 3)-ß-glucan content further increased ethanol yield providing a new strategy in energy crop breeding. Applying the (1, 3)-ß-glucan-optimized conversion method on marine biomass from brown macroalgae with a naturally high (1, 3)-ß-glucan content, we not only substantially increased ethanol yield but also demonstrated an effective co-fermentation of plant and marine biomass. This opens new perspectives in combining different kinds of feedstock for sustainable and efficient biofuel production, especially in coastal regions.

Kinetic and Structural Characterization of the Interaction of 6-Methylidene Penem 2 with the ß-Lactamase from Mycobacterium tuberculosis.

Mycobacterium tuberculosis is intrinsically resistant to most ß-lactam antibiotics because of the constitutive expression of the blaC-encoded ß-lactamase. This enzyme has extremely high activity against penicillins and cephalosporins, but weaker activity against carbapenems. The enzyme can be inhibited by clavulanate, avibactam, and boronic acids. In this study, we investigated the ability of 6-methylidene ß-lactams to inhibit BlaC. One such compound, penem 2, inhibited BlaC more than 70 times more efficiently than clavulanate. The compound forms a covalent complex with BlaC as shown by mass spectrometry. Crystallization of the complex revealed that the bound inhibitor was covalently attached via the Ser70 active site residue and that the covalently, acylated form of the inhibitor had undergone additional chemistry yielding a 4,7-thiazepine ring in place of the ß-lactam and a thiazapyroline ring generated as a result of ß-lactam ring opening. The stereochemistry of the product of the 7-endo-trig cyclization was the opposite of that observed previously for class A and D ß-lactamases. Addition of penem 2 greatly synergized the antibacterial properties of both ampicillin and meropenem against a growing culture of M. tuberculosis. Strikingly, penem 2 alone showed significant growth inhibition, suggesting that in addition to its capability of efficiently inhibiting BlaC, it also inhibited the peptidoglycan cross-linking transpeptidases.

A redox regulatory system critical for mycobacterial survival in macrophages and biofilm development.

Survival of M. tuberculosis in host macrophages requires the eukaryotic-type protein kinase G, PknG, but the underlying mechanism has remained unknown. Here, we show that PknG is an integral component of a novel redox homeostatic system, RHOCS, which includes the ribosomal protein L13 and RenU, a Nudix hydrolase encoded by a gene adjacent to pknG. Studies in M. smegmatis showed that PknG expression is uniquely induced by NADH, which plays a key role in metabolism and redox homeostasis. In vitro, RenU hydrolyses FAD, ADP-ribose and NADH, but not NAD+. Absence of RHOCS activities in vivo causes NADH and FAD accumulation, and increased susceptibility to oxidative stress. We show that PknG phosphorylates L13 and promotes its cytoplasmic association with RenU, and the phosphorylated L13 accelerates the RenU-catalyzed NADH hydrolysis. Importantly, interruption of RHOCS leads to impaired mycobacterial biofilms and reduced survival of M. tuberculosis in macrophages. Thus, RHOCS represents a checkpoint in the developmental program required for mycobacterial growth in these environments.

Born too small: who survives in the public hospitals in Lilongwe, Malawi?

OBJECTIVE: Malawi has the highest estimated preterm birth rate in the world. The survival rate of these babies is not known. The main objective of this study was to demonstrate the short-term survival of infants with birth weight below 2500 g nursed in Bwaila Hospital, a district hospital, and the tertiary level Kamuzu Central Hospital (KCH) in Lilongwe. The specific objectives were to calculate birth weight specific survival rates, compare the two hospitals regarding the chances of survival and review the use of antenatal corticosteroids. DESIGN: 1496 babies were included prospectively in the study between June and November 2012. Survival was defined as discharge from the nursery or postnatal ward. RESULTS: Survival was 7% for extremely low birth weight infants, 52% for very low birth weight and 90% for low birth weight (1500-2499 g). There was a marked increase in survival from 1100 g. Survival was significantly higher in KCH only for babies weighing below 1200 g. The majority of deaths occurred within the first 3 days of life. Only 98 of the babies had a mother who had received antenatal corticosteroids. CONCLUSIONS: With the current resources, we suggest focusing efforts on preventing early neonatal deaths in low birth weight infants above 1100 g in the hospitals in Lilongwe. The coverage of antenatal steroids for mothers at risk of preterm delivery can be improved. Further studies are needed on the quality of the obstetric and neonatal care at the hospitals and how to reduce the high rate of preterm birth in Malawi.

Can inhibitor-resistant substitutions in the Mycobacterium tuberculosis ß-Lactamase BlaC lead to clavulanate resistance?: a biochemical rationale for the use of ß-lactam-ß-lactamase inhibitor combinations.

The current emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis calls for novel treatment strategies. Recently, BlaC, the principal ß-lactamase of Mycobacterium tuberculosis, was recognized as a potential therapeutic target. The combination of meropenem and clavulanic acid, which inhibits BlaC, was found to be effective against even extensively drug-resistant M. tuberculosis strains when tested in vitro. Yet there is significant concern that drug resistance against this combination will also emerge. To investigate the potential of BlaC to evolve variants resistant to clavulanic acid, we introduced substitutions at important amino acid residues of M. tuberculosis BlaC (R220, A244, S130, and T237). Whereas the substitutions clearly led to in vitro clavulanic acid resistance in enzymatic assays but at the expense of catalytic activity, transformation of variant BlaCs into an M. tuberculosis H37Rv background revealed that impaired inhibition of BlaC did not affect inhibition of growth in the presence of ampicillin and clavulanate. From these data we propose that resistance to ß-lactam-ß-lactamase inhibitor combinations will likely not arise from structural alteration of BlaC, therefore establishing confidence that this therapeutic modality can be part of a successful treatment regimen against M. tuberculosis.

Granulomatous lung disease requiring mechanical ventilation induced by a single application of oxaliplatin-based chemotherapy for colorectal cancer: a case report.

Combined chemotherapeutic regimens in conjunction with oxaliplatin are considered safe and effective treatment options in the clinical management of metastatic colorectal cancer. A 62-year-old male patient with a metastatic rectal carcinoma developed a pulmonary reaction after the first application of the combined standard chemotherapy regimen (5-fluorouracil and sodium folinic acid as a 24 h infusion and oxaliplatin). Following the first dose of chemotherapy, the patient developed acute dyspnoea and fever. A computerised scan of the chest revealed bilateral pulmonary patchy consolidation. Despite high-dose empiric antibiotic and antimycotic treatment, no clinical improvement was seen. The patient's condition deteriorated, and he required invasive mechanical ventilation. Diagnostic thoracoscopic wedge resections were performed for further diagnosis. The histological workup revealed distinct granulomatous inflammation, but no microbial pathogens were to be found. Thereupon, a drug-induced reaction to chemotherapy was suspected and high-dose steroid treatment initiated. Subsequently, the patient's respiratory condition improved and he was extubated. The present case exemplifies the rare course of a bilateral pneumonia-like, drug-induced granulomatous reaction following a single application of oxaliplatin. In addition to the known side effects of oxaliplatin-containing combination chemotherapy, unexpected serious adverse events in the form of pulmonary toxicities should also be taken into account.

Molecular biology of drug resistance in Mycobacterium tuberculosis.

Tuberculosis (TB) has become a curable disease, thanks to the discovery of antibiotics. However, it has remained one of the most difficult infections to treat. Most current TB regimens consist of 6-9 months of daily doses of four drugs that are highly toxic to patients. The purpose of these lengthy treatments is to completely eradicate Mycobacterium tuberculosis, notorious for its ability to resist most antibacterial agents, thereby preventing the formation of drug resistant mutants. On the contrary, the prolonged therapies have led to poor patient adherence. This, together with a severe limit of drug choices, has resulted in the emergence of strains that are increasingly resistant to the few available antibiotics. Here, we review our current understanding of molecular mechanisms underlying the profound drug resistance of M. tuberculosis. This knowledge is essential for the development of more effective antibiotics, which are not only potent against drug resistant M. tuberculosis strains but also help shorten the current treatment courses required for drug susceptible TB.

Strategies for potentiation of ethionamide and folate antagonists against Mycobacterium tuberculosis.

Antifolates inhibit de novo folate biosynthesis, whereas ethionamide targets the mycolate synthetic pathway in Mycobacterium tuberculosis. These antibiotics are effective against M. tuberculosis but their use has been hampered by concerns over toxicity and low therapeutic indexes. With the increasing spread of drug-resistant forms, interest in using old drugs for tuberculosis treatment has been renewed. Specific inhibitors targeting resistance mechanisms could sensitize M. tuberculosis to these available, clinically approved drugs. This review discusses recently developed strategies to boost the antituberculous activity of ethionamide and antifolates. These approaches might help broaden the currently limited chemotherapeutic options of not only drug-resistant but also drug-susceptible tuberculosis, which still remains one of the most common infectious diseases in the developing world.

Long-Term Relapse-Free Survival by Interdisciplinary Collaboration in a Patient with Metastatic Pancreatic Cancer (UICC IV).

INTRODUCTION: The prognostic outlook for patients suffering from pancreatic cancer is generally poor. Particularly in cases of advanced and metastatic disease, long-term relapse-free survival may be achieved only in a few cases. CASE REPORT: A 45-year-old patient presented with metastatic pancreatic cancer. Liver metastases had been intra-operatively confirmed by histology. Prior to initiating treatment, a portacath was surgically implanted. Subsequently, the patient received a weekly dose of 1,000 mg/m(2) gemcitabine combined with 2,000 mg/m(2) high-dose 5-fluorouracil as a 24-hour infusion for palliative treatment. As the patient was suffering from a stenosis of the ductus hepaticus communis, an endoprosthesis was primarily implanted. After 18 applications of chemotherapy during which only low toxic side effects such as nausea, vomiting and alopecia (NCI-CTC grade 1) presented, a partial remission of the primary tumor was observed. In the course of chemotherapy treatment, the carbohydrate antigen 19-9 tumor marker value normalized. Thus, the interdisciplinary tumor board of the University of Erlangen decided to perform a laparoscopy to evaluate the status of liver metastases after palliative chemotherapy treatment. Subsequently, the primary tumor could be completely resected (pT2, pN0, pM0, L0, V0, G2, R0); liver metastases were not observed. Eight years after the initial diagnosis, the patient is relapse-free, professionally fully integrated and presents with an excellent performance status. CONCLUSION: Patients suffering from metastatic pancreatic cancer may benefit from treatment combinations with palliative intent. In singular cases, patients may even have a curative treatment option, provided a close interdisciplinary collaboration exists.

Palliative first-line therapy with weekly high-dose 5-fluorouracil and sodium folinic acid as a 24-hour infusion (AIO regimen) combined with weekly irinotecan in patients with metastatic adenocarcinoma of the stomach or esophagogastric junction followed by secondary metastatic resection after downsizing.

BACKGROUND: The aim of this retrospective study was to evaluate the efficacy and safety of weekly high-dose 5-fluorouracil (5-FU)/folinic acid (FA) as 24-h infusion (AIO regimen) plus irinotecan in patients with histologically proven metastatic gastroesophageal adenocarcinoma (UICC stage IV). MATERIAL/METHODS: From 08/1999 to 12/2008, 76 registered, previously untreated patients were evaluable. Treatment regimen: irinotecan (80 mg/m²) as 1-h infusion followed by 5-FU (2000 mg/m²) combined with FA (500 mg/m²) as 24-h infusion (d1, 8, 15, 22, 29, 36, qd 57). RESULTS: Median age: 59 years; male/female: 74%/26%; ECOG ≤1: 83%; response: CR: 1%, PR: 16%, SD: 61%, PD: 17%, not evaluable in terms of response: 5%; tumor control: 78%; median OS: 11.2 months; median time-to-progression: 5.3 months; 1-year survival rate: 49%; 2-year survival rate: 17%; no evidence of disease: 6.6%; higher grade toxicities (grade 3/4): anemia: 7%, leucopenia: 1%, ascites: 3%, nausea: 3%, infections: 12%, vomiting: 9%, GI bleeding of the primary tumor: 4%, diarrhea: 17%, thromboembolic events: 4%; secondary metastatic resection after downsizing: 16 patients (21%), R-classification of secondary resections: R0/R1/R2: 81%/6%/13%, median survival of the 16 patients with secondary resection: 23.7 months. CONCLUSIONS: Combined 5-FU/FA as 24-h infusion plus irinotecan may be considered as an active palliative first-line treatment accompanied by tolerable toxicity; thus offering an alternative to cisplatin-based treatment regimens. Thanks to efficient interdisciplinary teamwork, secondary metastatic resections could be performed in 16 patients. In total, the patients who had undergone secondary resection had a median survival of 23.7 months, whereas the median survival of patients without secondary resection was 10.1 months (p≤0.001).

A lipoprotein modulates activity of the MtrAB two-component system to provide intrinsic multidrug resistance, cytokinetic control and cell wall homeostasis in Mycobacterium.

The MtrAB signal transduction system, which participates in multiple cellular processes related to growth and cell wall homeostasis, is the only two-component system known to be essential in Mycobacterium. In a screen for antibiotic resistance determinants in Mycobacterium smegmatis, we identified a multidrug-sensitive mutant with a transposon insertion in lpqB, the gene located immediately downstream of mtrA-mtrB. The lpqB mutant exhibited increased cell-cell aggregation and severe defects in surface motility and biofilm growth. lpqB cells displayed hyphal growth and polyploidism, reminiscent of the morphology of Streptomyces, a related group of filamentous Actinobacteria. Heterologous expression of M. tuberculosis LpqB restored wild-type characteristics to the lpqB mutant. LpqB interacts with the extracellular domain of MtrB, and influences MtrA phosphorylation and promoter activity of dnaA, an MtrA-regulated gene that affects cell division. Furthermore, in trans expression of the non-phosphorylated, inactive form of MtrA in wild-type M. smegmatis resulted in phenotypes similar to those of lpqB deletion, whereas expression of the constitutively active form of MtrA restored wild-type characteristics to the lpqB mutant. These results support a model in which LpqB, MtrB and MtrA form a three-component system that co-ordinates cytokinetic and cell wall homeostatic processes.

Palliative first-line treatment with weekly high-dose 5-fluorouracil as 24h-infusion and gemcitabine in metastatic pancreatic cancer (UICC IV).

BACKGROUND: The aim of this study was to evaluate the efficacy and toxic side effects of combined gemcitabine plus weekly high-dose 5-Fluorouracil (5-FU) as 24h-infusion in patients with metastatic pancreatic cancer (UICC IV) as validation group of an earlier phase II study. Primary endpoints were to assess the response and tumour control rate. MATERIAL/METHODS: This study comprised 60 prospectively registered patients with metastatic pancreatic cancer (UICC IV). A locally advanced disease was defined as exclusion criteria. The treatment schedule was weekly gemcitabine (1.000 mg/m(2)) as a 0.5h-infusion combined with 5-FU (2.000 mg/m(2)) as a 24h-infusion on day 1, 8 and 15 every 28 days. RESULTS: Response rate (CR+PR) was achieved in 7% of the patients, tumour control rate (CR+PR+SD) was achieved in 59%. Median time-to-progression was 4 months, median overall survival was 7.3 months (95% CI 5.4-9.1). The median survival of patients with normal CEA value was 10.6 months (95% CI 7.8-13.4); with a normal CA 19-9 median survival was 10.1 months (95% CI 4.6-15.7) and with ECOG performance status 0 median survival was 10.1 months (95% CI 8.6-15.3). As higher grade toxicity (grade 3/4) leukopenia (15%), anaemia (10%) and thrombopenia (5%) were observed. Nausea and diarrhea (grade 3/4) occurred in 5% of the patients and vomiting in 2%. CONCLUSIONS: The administration of gemcitabine and 5-FU as a 24h-infusion is feasible and offers good tumour control rate accompanied by tolerable toxicity. The subgroup of patients with a good performance status (ECOG 0) and tumour markers within the normal range benefit from the gemcitabine combination therapy.

Protein kinase G is required for intrinsic antibiotic resistance in mycobacteria.

Antibiotic resistance and virulence of pathogenic mycobacteria are phenotypically associated, but the underlying genetic linkage has not been known. Here we show that PknG, a eukaryotic-type protein kinase previously found to support survival of mycobacteria in host cells, is required for the intrinsic resistance of mycobacterial species to multiple antibiotics.