Melanomas are highly proliferative and invasive, and are most frequently metastatic. Despite many advances in cancer treatment over the last several decades, the prognosis for patients with advanced melanoma remains poor. New treatment methods and strategies are necessary. The main hallmark of cancer is uncontrolled cellular proliferation with alterations in the expression of proteins. Ubiquitin and ubiquitin-related proteins posttranslationally modify proteins and thereby alter their functions. The ubiquitination process is involved in various physiological responses, including cell growth, cell death, and DNA damage repair. E3 ligases, the most specific enzymes of ubiquitination system, participate in the turnover of many key regulatory proteins and in the development of cancer. E3 ligases are of interest as drug targets for their ability to regulate proteins stability and functions. Compared to the general proteasome inhibitor bortezomib, which blocks the entire protein degradation, drugs that target a particular E3 ligase are expected to have better selectivity with less associated toxicity. Components of different E3 ligases complexes (FBW7, MDM2, RBX1/ROC1, RBX2/ROC2, cullins and many others) are known as oncogenes or tumor suppressors in melanomagenesis. These proteins participate in regulation of different cellular pathways and such important proteins in cancer development as p53 and Notch. In this review we summarized published data on the role of known E3 ligases in the development of melanoma and discuss the inhibitors of E3 ligases as a novel approach for the treatment of malignant melanomas.

BackgroundThe α/β ratio for prostate cancer is postulated being in the range of 0.8 to 2.2 Gy, giving rise to the hypothesis that there may be a therapeutic advantage to hypofractionation. To do so, we carried out a randomized trial comparing hypofractionated and conventionally fractionated image-guided intensity modulated radiotherapy (IG-IMRT) in high-risk prostate cancer. Here, we report on acute toxicity and quality of life (QOL) for the first 124 randomized patients.MethodsThe trial compares 76 Gy in 38 fractions (5 fractions/week) (Arm 1) to 63 Gy in 20 fractions (4 fractions/week) (Arm 2) (IG-IMRT). Prophylactic pelvic lymph node irradiation with 46 Gy in 23 fractions sequentially (Arm 1) and 44 Gy in 20 fractions simultaneously (Arm 2) was applied. All patients had long term androgen deprivation therapy (ADT) started before RT. Both physician-rated acute toxicity and patient-reported QOL using EPIC questionnaire are described.ResultsThere were no differences in overall maximum acute gastrointestinal (GI) or genitourinary (GU) toxicity. Compared to conventional fractionation (Arm 1), GI and GU toxicity both developed significantly earlier but also disappeared earlier in the Arm 2, reaching significant differences from Arm 1 at week 8 and 9. In multivariate analyses, only parameter shown to be related to increased acute Grade ≥1 GU toxicity was the study Arm 2 (p = 0.049). There were no statistically significant differences of mean EPIC scores in any domain and sub-scales. The clinically relevant decrease (CRD) in EPIC urinary domain was significantly higher in Arm 2 at month 1 with a faster recovery at month 3 as compared to Arm 1.ConclusionsHypofractionation at 3.15 Gy per fraction to 63 Gy within 5 weeks was well tolerated. The GI and GU physician-rated acute toxicity both developed earlier but recovered faster using hypofractionation. There was a correlation between acute toxicity and bowel and urinary QOL outcomes. Longer follow-up is needed to determine the significance of these associations with late toxicity.

The initial host response to Mycobacterium tuberculosis is driven by innate immunity. For this study, we examined the ability of 18 recent clinical isolates and 5 reference strains to survive and replicate in the context of host innate immunity by using whole blood culture. Six healthy tuberculin-negative volunteers served as subjects. H 37 Ra showed the least capacity to replicate of any of the strains tested, decreasing in viability 1.3 log CFU during 72 h of whole blood culture, whereas H 37 Rv increased 0.32 log. Clinical isolates varied greatly in their ability to replicate in blood cells, ranging from ؊0.4 to ؉0.8 log (P < 0.001). Four showed significantly more growth than H 37 Rv, and one showed significantly reduced growth. Host mechanisms for restricting intracellular mycobacterial growth were more effective during the first 24 h of whole blood culture than during the 24-to 72-h period. Certain mycobacterial isolates appeared preferentially able to withstand host defenses during each of these intervals. Although there was relatively more homogeneity among subjects than among strains, one of the six subjects showed a reduced capacity to restrict intracellular mycobacterial growth due to a defect expressed during the first 24 h of culture. Our findings indicate substantial variability in the capacity of clinical tuberculosis isolates to replicate in host cells in the face of innate host immunity.The early events following inhalation by an immunocompetent, mycobacterium-naïve host of droplet nuclei containing viable Mycobacterium tuberculosis are driven by the innate immune system. The resulting influx of neutrophils, macrophages, NK cells, and other cells to the site of infection serves as a stimulus for granuloma formation and acts directly to limit the extent of mycobacterial replication at this early stage of infection. It has been suggested that the efficiency of these early innate responses may help determine whether a latent infection is established and whether that infection ultimately will progress to active disease.Through evolutionary selection, pathogenic mycobacteria have acquired means to evade specific host immune effector mechanisms, presumably including those of the innate response. The propensity of certain M. tuberculosis isolates to cause outbreaks, for example, has been linked to increased virulence in macrophages or mice in association with altered host cytokine expression profiles (2,3,6,8,12). However, even these virulent outbreak-associated isolates cause disease in only a small proportion of infected individuals. Our understanding of the interplay of biologic and genetic diversity in the host and in the mycobacterium is incomplete, in part because current models to examine the early events in mycobacterial pathogenesis have not been well suited to field or epidemiologic human studies.For the present study, we assessed the capacity of mycobacterial strains to survive phagocytosis and replicate in whole blood cultures. This model permits the involvement of neutrophils, as well as mo...

The pandemic spread of the COVID-19 virus significantly affected daily life, but the highest pressure was piled on the health care system. Our aim was to evaluate an impact of COVID-19 pandemic management measures on cancer services at the National Cancer Institute (NCI) of Lithuania. We assessed the time period from 1 February 2020 to 31 December 2020 and compared it to the same period of 2019. Data for our analysis were extracted from the NCI Hospital Information System (HIS) and the National Health Insurance Fund (NHIF). Contingency table analysis and ANOVA were performed. The COVID-19 pandemic negatively affected the cancer services provided by NCI. Reductions in diagnostic radiology (−16%) and endoscopy (−29%) procedures were accompanied by a decreased number of patients with ongoing medical (−30%), radiation (−6%) or surgical (−10%) treatment. The changes in the number of newly diagnosed cancer patients were dependent on tumor type and disease stage, showing a rise in advanced disease at diagnosis already during the early period of the first lockdown. The extent of out-patient consultations (−14%) and disease follow-up visits (−16%) was also affected by the pandemic, and only referrals to psychological/psychiatric counselling were increased. Additionally, the COVID-19 pandemic had an impact on the structure of cancer services by fostering the application of modified systemic anticancer therapy or hypofractionated radiotherapy. The most dramatic drop occurred in the number of patients participating in cancer prevention programs; the loss was 25% for colon cancer and 62% for breast cancer screening. Marked restriction in access to preventive cancer screening and overall reduction of the whole spectrum of cancer services may negatively affect cancer survival measures in the nearest future.

The activity of oral clofazimine against intracellular Mycobacterium tuberculosis was compared to that of ofloxacin in healthy volunteers by the use of whole-blood cultures. Clofazimine was inactive whether it was tested alone or combined with other drugs that are used to treat multidrug-resistant tuberculosis, despite a total dose of 2 g. Kanamycin was the most active drug tested.Multidrug-resistant tuberculosis (MDR TB) poses a growing public health problem. Studies to assess tissue sterilization in MDR TB are particularly long and complex. Members of our laboratory recently described a method for studying the ability of administered chemotherapy to kill intracellular Mycobacterium tuberculosis cells by using whole-blood cultures (14). In patients with drug-sensitive TB, the whole-blood bactericidal activity (WBA) was correlated with two sputum markers of tissue sterilization, the 8-week sputum culture conversion and the serial sputum CFU slope (16). In the present study, the whole-blood model was used to examine the potential role of clofazimine in the treatment of MDR TB.Our subjects consisted of 10 healthy tuberculin-nonreactive volunteers who provided written informed consent according to an Institutional Review Board-approved protocol. They were randomly assigned to receive only ofloxacin (600 mg) or clofazimine (200 mg) daily for 5 days. Pyrazinamide (25 mg/kg of body weight) was added on days 6 to 10. Ethambutol (25 mg/kg) was added on day 10. This schedule permitted the intracellular accumulation of clofazimine, ofloxacin, and pyrazinamide in phagocytic cells. Kanamycin was added to wholeblood cultures at final concentrations of 20 and 10 g/ml in blood specimens at 2 and 6 h postdose, respectively, to mimic blood levels of 40 and 20 g/ml, respectively. Drug addition was delayed 30 min after infection to allow for phagocytosis.WBA was assessed as previously described (5, 14, 16). Briefly, heparinized blood was diluted 1:1 with medium and infected with M. tuberculosis H37Rv. Members of our laboratory previously documented the high efficiency of phagocytosis in whole-blood cultures (Ͼ95%) by examining CFU counts in the liquid and cellular partitions after low-speed sedimentation and by showing the lack of effect of amoxicillin-clavulanate, which does not reach adequate intracellular levels to act against M. tuberculosis (14); this eliminates the need to remove extracellular bacilli. After 72 h of incubation, the host cells were disrupted by hypotonic lysis, and bacilli were sedimented and inoculated into BACTEC medium. Bacillus killing was calculated based on days-to-positivity by using a standard curve. The total bactericidal effect was assessed as the area under the curve (AUC) (16). The results were examined by a paired or unpaired t test.At the baseline, there was a net growth of M. tuberculosis H37Rv of 0.41 log CFU over 72 h in the subjects' blood cells. A single dose of clofazimine had no effect in blood sampled 2 h afterward (mean, 0.42 log CFU; P ϭ 0.3), whereas the corresponding effect of ofloxa...