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Drug resistance constitutes a major challenge in designing melanoma therapies. Microenvironment-driven tumor heterogeneity and plasticity play a key role in this phenomenon. Melanoma is highly heterogeneous with diverse genomic alterations and expression of different biological markers. In addition, melanoma cells are highly plastic and capable of adapting quickly to changing microenvironmental conditions. These contribute to variations in therapy response and durability between individual melanoma patients. In response to changing microenvironmental conditions, like hypoxia and nutrient starvation, proliferative melanoma cells can switch to an invasive slow-cycling state. Cells in this state are more aggressive and metastatic, and show increased intrinsic drug resistance. During continuous treatment, slow-cycling cells are enriched within the tumor and give rise to a new proliferative subpopulation with increased drug resistance, by exerting their stem cell-like behavior and phenotypic plasticity. In melanoma, the proliferative and invasive states are defined by high and low microphthalmia-associated transcription factor (MITF) expression, respectively. It has been observed that in MITFhigh melanomas, inhibition of MITF increases the efficacy of targeted therapies and delays the acquisition of drug resistance. Contrarily, MITF is downregulated in melanomas with acquired drug resistance. According to the phenotype switching theory, the gene expression profile of the MITFlow state is predominantly regulated by WNT5A, AXL, and NF-κB signaling. Thus, different combinations of therapies should be effective in treating different phases of melanoma, such as the combination of targeted therapies with inhibitors of MITF expression during the initial treatment phase, but with inhibitors of WNT5A/AXL/NF-κB signaling during relapse.

Francisella tularensis is a zoonotic, Gram-negative coccobacillus that causes tularemia in humans and animals. F. tularensis subspecies tularensis (type A) and F. tularensis subspecies holarctica (type B) are antigenically similar and more virulent than Francisella novicida in humans. The genetic locus that encodes the LPS O antigen was found to be substantially different between the type B live vaccine strain (LVS) and F. novicida. One LVS-specific gene with homology to a galactosyl transferase was selected for allelic replacement using a sacB-chloramphenicol expression suicide plasmid, and recombinants were screened for colony morphology on Congo red agar that matched that of F. novicida. Two mutants (WbtI S187Y and WbtI G191V ) were isolated that contained substitutions in conserved motifs in the sugar transamine/perosamine synthetase (WbtI) of the O-antigen locus, and the latter mutant was extensively tested and characterized. WbtI G191V grew at the same rate as the parent strain in Chamberlain's defined medium, completely lacked O antigen, was serum-sensitive but could grow in a mouse macrophage cell line, had increased resistance to sodium deoxycholate, and was highly attenuated in mice. Complementation of WbtI G191V with the wild-type wbtI gene in trans restored normal LPS synthesis, phenotypic properties similar to the parent, and virulence in mice. Immunization with WbtI G191V protected mice against a relatively low-dose intraperitoneal challenge with LVS, but was less protective against a high-dose challenge. These results indicate that complete loss of O antigen alters the surface phenotype and abrogates virulence in F. tularensis, but also compromises the induction of full protective immunity against F. tularensis infection in mice.

Escherichia coli has eight genes predicted to encode sulfurtransferases having the active site consensus sequence Cys-Xaa-Xaa-Gly. One of these genes, ybbB, is frequently found within bacterial operons that contain selD, the selenophosphate synthetase gene, suggesting a role in selenium metabolism. We show that ybbB is required in vivo for the specific substitution of selenium for sulfur in 2-thiouridine residues in E. coli tRNA. This modified tRNA nucleoside, 5-methylaminomethyl-2-selenouridine (mnm 5 se 2 U), is located at the wobble position of the anticodons of tRNA Lys , tRNA Glu , and tRNA 1Gln . Nucleoside analysis of tRNAs from wild-type and ybbB mutant strains revealed that production of mnm 5 se 2 U is lost in the ybbB mutant but that 5-methylaminomethyl-2-thiouridine, the mnm 5 se 2 U precursor, is unaffected by deletion of ybbB. Thus, ybbB is not required for the initial sulfurtransferase reaction but rather encodes a 2-selenouridine synthase that replaces a sulfur atom in 2-thiouridine in tRNA with selenium. Purified 2-selenouridine synthase containing a C-terminal His 6 tag exhibited spectral properties consistent with tRNA bound to the enzyme. In vitro mnm 5 se 2 U synthesis is shown to be dependent on 2-selenouridine synthase, SePO 3 , and tRNA. Finally, we demonstrate that the conserved Cys 97 (but not Cys 96 ) in the rhodanese sequence motif Cys 96 -Cys 97 -Xaa-Xaa-Gly is required for 2-selenouridine synthase in vivo activity. These data are consistent with the ybbB gene encoding a tRNA 2-selenouridine synthase and identifies a new role for the rhodanese homology domain in enzymes.

Three-dimensional (3D) tumor spheroids are utilized in cancer research as a more accurate model of the in vivo tumor microenvironment, compared to traditional two-dimensional (2D) cell culture. The spheroid model is able to mimic the effects of cell-cell interaction, hypoxia and nutrient deprivation, and drug penetration. One characteristic of this model is the development of a necrotic core, surrounded by a ring of G1 arrested cells, with proliferating cells on the outer layers of the spheroid. Of interest in the cancer field is how different regions of the spheroid respond to drug therapies as well as genetic or environmental manipulation. We describe here the use of the fluorescence ubiquitination cell cycle indicator (FUCCI) system along with cytometry and image analysis using commercial software to characterize the cell cycle status of cells with respect to their position inside melanoma spheroids. These methods may be used to track changes in cell cycle status, gene/protein expression or cell viability in different sub-regions of tumor spheroids over time and under different conditions. Video LinkThe video component of this article can be found at

Background: Lung cancer is the leading cause of cancer death worldwide Therefore, identification of genetic as well as environmental factors is very important in developing novel methods of lung cancer prevention. However, this is a multi-layered problem. Therefore a lung cancer risk prediction system is here proposed which is easy, cost effective and time saving. Materials and Methods: Initially 400 cancer and non-cancer patients' data were collected from different diagnostic centres, pre-processed and clustered using a K-means clustering algorithm for identifying relevant and non-relevant data. Next significant frequent patterns are discovered using AprioriTid and a decision tree algorithm. Results: Finally using the significant pattern prediction tools for a lung cancer prediction system were developed. This lung cancer risk prediction system should prove helpful in detection of a person's predisposition for lung cancer. Conclusions: Most of people of Bangladesh do not even know they have lung cancer and the majority of cases are diagnosed at late stages when cure is impossible. Therefore early prediction of lung cancer should play a pivotal role in the diagnosis process and for an effective preventive strategy.

ObjectivesThe aims of the research are to examine the problems of abnormal menopausal women: the relationship between depression and menopausal-specific quality of life (MENQOL)-symptoms among postmenopausal women; the association of MENQOL-symptoms between pre- and postmenopausal female society in Bangladeshi real community.MethodsThis cross sectional study was conducted on 435 women of Tangail, aged (≥ 17) years, using a structured questionnaire where is inaacluded the information of MENQOL and one of the main outcomes “depression” is measured by beck depression inventory.ResultsMenopausal status and MENQOL symptoms (except pain) are significantly (P < 0.05) associated. By using post-hoc analysis, the proportion of menopausal women, classified as having a depressive mood of early menopause is significantly higher than natural-menopause. Among postmenopausal women, there is a significant correlation between “concentration problem” and “depression”. Here mean depression score (29.40 ± 6.42) of menopausal women who have any difficulty in concentrating is higher than mean depression score (20.89 ± 6.64) of menopausal women who have no difficulty in concentrating. Another six factors (osteoporosis, heart-beating, fatigue, pressure, tingling, headaches) of MENQOL-symptoms were significantly correlated with depression and P-values are 0.000, 0.000, 0.000, 0.033, 0.006, and 0.002, respectively. Finally the presence of “difficulty in concentrating” and “fatigue” are strongly associated factors with depression score (P < 0.001).ConclusionsThe early postmenopausal women have to face more psychological problems (e.g., depression) compare to others. Among postmenopausal women, there is no significant relation between depression and vasomotor symptom (e.g., hot-flashes) perspective to menopausal female society of Bangladesh.

ObjectivesEvery physical abnormal criterion has an impact on the health. Late menopause causes different physiological problems which alike early menopause. The research interest is associated with both early and late menopausal women of Bangladesh as only few menopausal studies available in South East Asia especially in Bangladesh. The aims of this study are not only to assess the symptoms of menopausal abnormality but also to determine the impact of these symptoms on the quality of life (QOL) of the female society in Bangladesh.MethodsData mining techniques are used to rank the 22 factors (conducted with questionnaire) commonly associated with menopause. Among the participants menstruation that stops before 45 years was considered as early menopausal status and after 50 years as late menopausal. The mean of age and mean length of time in years, since menopause for all participants were 61.55±10.7 and 14.13±11.17, respectively. Recorded data indicated 67% were early menopausal women and 33% were late menopausal women.ResultsResults indicated that feeling tired or lacking in energy and dizziness (83%) and depression (82%) have worst impact on QOL among all factors, respectively. The next prevalent symptoms included hot flashes (64%), osteoporosis (72%), sweating at night (63%), concentration problem (75%), irritability (63%), feeling tense (77%), headache (66%). However, less frequent factors included breathing problems (33%), loss of feeling (31%), coherent heart disease (13%) and type2 diabetics (9%).ConclusionOur study indicates that early menopausal women are facing more physiological problems than the late menopausal women on their QOL.