Abstract P3-03-18: An ex-vivo platform predicts anti-tumor outcome of metabolically-targeted, algorithm-driven combination therapy in triple-negative breast cancer

Cancer cells undergo phenotypic cell state transitions in response to chemotherapy as a mechanism that can confer transient resistance. However, such cell state transitions can also unlock unique vulnerabilities that can be exploited using temporally-sequenced combination chemotherapy. Here, utilizing a primary breast cancer ex-vivo functional assay that captures tumor heterogeneity, we report that in response to a chemotherapeutic agent, a subset of cancer cells can mount an acutely-induced phenotypic adaptive resistance to future cytotoxic pressure via the transient acquisition of a unique metabolic state defined by augmented glycolysis together with mitochondrial proficiency. These cells activate two complex, temporally-interdependent pathways that enable a glucose shunt towards the pentose phosphate pathway (PPP), which confers an adaptive cross-tolerance to different chemotherapeutic agents. Mathematically modeling these pathways, and simulating drug schedules, we define a rationally-designed 3-drug combination therapy of metabolic inhibitors and cytotoxic agents, which results in improved cancer survival. Our findings highlight a new bioenergetics-based adaptive resistance mechanism through which cancer cells can survive combinations of chemotherapy. Administration of metabolic inhibitors in rational, temporal sequence with existing chemotherapy can emerge as a new paradigm in the treatment of cancer.

Citation Format: Goldman A, Majumder B, Dhawan A, Kohandel M, Majumder P, Sengupta S. An ex-vivo platform predicts anti-tumor outcome of metabolically-targeted, algorithm-driven combination therapy in triple-negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-03-18.

Medium-sized congenital melanocytic nevus of the forehead, glabella and temple – surgical treatment and long-term follow-up

Congenital melanocytic nevi can be stigmatising for the patient. Larger nevi bear an increased risk for melanoma development. Large congenital melanocytic nevi may be a symptom of neurocutaneous melanosis. We report on a 5-year-old boy with an extensive hair-bearing facial congenital melanocytic nevus, covering forehead, glabella and temple region associated with unilateral brow and blepharoptosis. The lesion was excised en bloc. The resulting defect had been closed by full thickness skin graft. Healing was unremarkable and long-term follow-up over 13 years demonstrated a satisfying esthetic and functional outcome. There was no evidence of melanoma development. Surgery is an option for disfiguring larger congenital melanocytic nevi as long as esthetics and function can be preserved. Long-term follow-up is recommended due to the increased risk of melanoma.

[Esthetic dermatology for the elderly]

Esthetic dermatology discovers older age. Methods and techniques which are useful in younger people need modifications to meet the special needs of the elderly. These aspects are discussed with a focus on the aging face. Esthetic dermatology is most successful when using principles of regenerative medicine.

Homologous prime-boost strategy with TgPI-1 improves the immune response and protects highly susceptible mice against chronic Toxoplasma gondii infection

Subunit-based vaccines are safer than live or attenuated pathogen vaccines, although they are generally weak immunogens. Thus, proper combination of immunization strategies and adjuvants are needed to increase their efficacy. We have previously protected C3H/HeN mice from Toxoplasma gondii infection by immunization with the serine protease inhibitor-1 (TgPI-1) in combination with alum. In this work, we explore an original vaccination protocol that combines administration of recombinant TgPI-1 by intradermal and intranasal routes in order to enhance protection in the highly susceptible C57BL/6 strain. Mice primed intradermally with rTgPI-1 plus alum and boosted intranasally with rTgPI-1 plus CpG-ODN elicited a strong specific Th1/Th2 humoral response, along with a mucosal immune response characterized by specific-IgA in intestinal lavages. A positive cellular response of mesentheric lymph node cells and Th1/Th2 cytokine secretion in the ileon were also detected. When immunized mice were challenged with the cystogenic Me49 T. gondii strain, they displayed up to 62% reduction in brain parasite burden. Moreover, adoptive transfer of mesenteric lymph node cells from vaccinated to naïve mice induced significant protection against infection. These results demonstrate that this strategy that combines the administration of TgPI-1 by two different routes, intradermal priming and intranasal boost, improves protective immunity against T. gondii chronic infection in highly susceptible mice.

Regulatory cells induced by acute toxoplasmosis prevent the development of allergic lung inflammation

The increased prevalence of allergies in developed countries has been attributed to a reduction of some infections. Supporting epidemiological studies, we previously showed that both acute and chronic Toxoplasma gondii infection can diminish allergic airway inflammation in BALB/c mice. The mechanisms involved when sensitization occurs during acute phase would be related to the strong Th1 response induced by the parasite. Here, we further investigated the mechanisms involved in T. gondii allergy protection in mice sensitized during acute T. gondii infection. Adoptive transference assays and ex vivo co-cultures experiments showed that not only thoracic lymph node cells from infected and sensitized mice but also from non-sensitized infected animals diminished both allergic lung inflammation and the proliferation of effector T cells from allergic mice. This ability was found to be contact-independent and correlated with high levels of CD4(+)FoxP3(+) cells. IL-10 would not be involved in allergy suppression since IL-10-deficient mice behaved similar to wild type mice. Our results extend earlier work and show that, in addition to immune deviation, acute T. gondii infection can suppress allergic airway inflammation through immune suppression.

Plant heat shock protein 90 as carrier-adjuvant for immunization against a reporter antigen

Here, we evaluated the modulation of the immune response induced by Hsp90 of Nicotiana benthamiana (NbHsp90.3) against the Maltose Binding Protein (MBP) as a reporter antigen. Equimolar quantities of recombinant proteins were administered in mice as follows: MBP alone (MBP group), a mixture of MBP and rNbHsp90.3 (MBP+rNbHsp90.3 group) and the fusion of MBP to rNbHsp90.3 (MBP-rNbHsp90.3 group). The covalent linkage between NbHsp90.3 and MBP to bring a fusion protein was essential to induce the strong specific antibody response with predominance of IgG2a. Eighty-four days after the first immunization, splenocyte proliferation from MBP-rNbHsp90.3-immunized mice was consistently higher than that from MBP and MBP+rNbHsp90.3 groups. In addition, splenocytes from MBP-rNbHsp90.3 immunized mice produced higher levels of IFN-γ than controls. Finally, both formulations with rNbHsp90.3 significantly enhanced the MHC class I expression levels, but only rNbHsp90.3 covalent bound to MBP induced a specific cellular immune response against MBP measured as increased percentage of CD8(+) T cells. Taken together, these results suggest that plant HSP90s could be incorporated as adjuvants in vaccines that require the generation of a Th1 response along with a CD8 cytotoxic cell response to confer immunity.

Microbes bind complement inhibitor factor H via a common site

To cause infections microbes need to evade host defense systems, one of these being the evolutionarily old and important arm of innate immunity, the alternative pathway of complement. It can attack all kinds of targets and is tightly controlled in plasma and on host cells by plasma complement regulator factor H (FH). FH binds simultaneously to host cell surface structures such as heparin or glycosaminoglycans via domain 20 and to the main complement opsonin C3b via domain 19. Many pathogenic microbes protect themselves from complement by recruiting host FH. We analyzed how and why different microbes bind FH via domains 19–20 (FH19-20). We used a selection of FH19-20 point mutants to reveal the binding sites of several microbial proteins and whole microbes (Haemophilus influenzae, Bordetella pertussis, Pseudomonas aeruginosa, Streptococcus pneumonia, Candida albicans, Borrelia burgdorferi, and Borrelia hermsii). We show that all studied microbes use the same binding region located on one side of domain 20. Binding of FH to the microbial proteins was inhibited with heparin showing that the common microbial binding site overlaps with the heparin site needed for efficient binding of FH to host cells. Surprisingly, the microbial proteins enhanced binding of FH19-20 to C3b and down-regulation of complement activation. We show that this is caused by formation of a tripartite complex between the microbial protein, FH, and C3b. In this study we reveal that seven microbes representing different phyla utilize a common binding site on the domain 20 of FH for complement evasion. Binding via this site not only mimics the glycosaminoglycans of the host cells, but also enhances function of FH on the microbial surfaces via the novel mechanism of tripartite complex formation. This is a unique example of convergent evolution resulting in enhanced immune evasion of important pathogens via utilization of a “superevasion site.”

Complement is an important arm of innate immunity. Activation of this plasma protein cascade leads to opsonization of targets for phagocytosis, direct lysis of Gram-negative bacteria, and enhancement of the inflammatory and acquired immune responses. No specific signal is needed for activation of the alternative pathway of complement, leading to its activation on all unprotected surfaces. Pathogenic microbes need to evade this pathway, and several species are known to recruit host complement inhibitor factor H (FH) to prevent the activation. FH is important for protection of host cells, too, as defects in FH lead to a severe autoreactive disease, atypical hemolytic uremic syndrome. We have now identified at the molecular level a common mechanism by which seven different microbes, Haemophilus influenzae, Bordetella pertussis, Pseudomonas aeruginosa, Streptococcus pneumoniae, Candida albicans, Borrelia burgdorferi and B. hermsii, recruit FH. All microbes bind FH via a common site on domain 20, which facilitates formation of a tripartite complex between the microbial protein, the main complement opsonin C3b, and FH. We show that, by utilizing the common microbial binding site on FH20, microbes can inhibit complement more efficiently. This detailed knowledge on mechanism of complement evasion can be used in developing novel antimicrobial chemotherapy.

[Side effects in aesthetic medicine. Spectrum, management and avoidance]

Aesthetic medicine has become increasingly popular in the last two decades. The same trend has occurred in dermatology. Aesthetic dermatology prefers minimally invasive procedures. Nevertheless, even these procedures are not free of possible adverse effects. The spectrum of possible adverse effects, their management and prevention are discussed for four popular procedures in aesthetic dermatology, i.e. chemical peels, mesotherapy, botulinum toxin, and dermal fillers. Aesthetic procedures should only be performed by well-educated, well-trained medical doctors with an excellent medical background, never by lay persons.

Plant Hsp90 proteins interact with B-cells and stimulate their proliferation

BACKGROUND

The molecular chaperone heat shock protein 90 (Hsp90) plays an important role in folding stabilization and activation of client proteins. Besides, Hsp90 of mammals and mammalian pathogens displays immunostimulatory properties. Here, we investigated the role of plant-derived Hsp90s as B-cell mitogens by measuring their proliferative responses in vitro.

METHODOLOGY

Plant cytosolic Hsp90 isoforms from Arabidopsis thaliana (AtHsp81.2) and Nicotiana benthamiana (NbHsp90.3) were expressed in E. coli. Over-expression of recombinant plant Hsp90s (rpHsp90s) was confirmed by SDS-PAGE and western blot using and anti-AtHsp81.2 polyclonal anti-body. Both recombinant proteins were purified by Ni-NTA affinity chromatography and their identity confirmed by MALDI-TOF-TOF. Recombinant AtHsp81.2 and NbHsp90.3 proteins induced prominent proliferative responses in spleen cells form BALB/c mice. Polymyxin-B, a potent inhibitor of lipopolysaccharide (LPS), did not eliminate the rpHsp90-induced proliferation. In addition, in vitro incubation of spleen cells with rpHsp90 led to the expansion of CD19-bearing populations, suggesting a direct effect of these proteins on B lymphocytes. This effect was confirmed by immunofluorescence analysis, where a direct binding of rpHsp90 to B- but not to T-cells was observed in cells from BALB/c and C3H/HeN mice. Finally, we examined the involvement of Toll Like Receptor 4 (TLR4) molecules in the rpHsp90s induction of B-cell proliferation. Spleen cells from C3H/HeJ mice, which carry a point mutation in the cytoplasmic region of TLR4, responded poorly to prAtHsp90. However, the interaction between rpHsp90 and B-cells from C3H/HeJ mice was not altered, suggesting that the mutation on TLR4 would be affecting the signal cascade but not the rpHsp90-TLR4 receptor interaction.

CONCLUSIONS

Our results show for the first time that spleen cell proliferation can be stimulated by a non-pathogen-derived Hsp90. Furthermore, our data provide a new example of a non-pathogen-derived ligand for TLRs.

Combination of CpG-oligodeoxynucleotides with recombinant ROP2 or GRA4 proteins induces protective immunity against Toxoplasma gondii infection

Synthetic oligodeoxynucleotides containing unmethylated CpG motifs (CpG-ODN) have been characterized as Th1-promoting immunopotentiators, an adjuvant activity desirable for vaccination against intracellular parasites like Toxoplasma gondii. In an attempt to find new antigen-adjuvant combinations that enhance the immunogenicity of antigen candidates for toxoplasma vaccines, we analyzed the extent of protection in mice immunized with ROP2 and GRA4 recombinant proteins when co-administered with CpG-ODN. Both GRA4+CpG-ODN and ROP2+CpG-ODN formulations were shown to induce a strong humoral Th1-biased response characterized by a high IgG(2a) to IgG(1) antibody ratio. Both vaccination regimens led to increased secretion of IFN-γ and IL-10, and negligible amounts of IL-4, upon specific re-stimulation of spleen cells from these groups of mice. After a non-lethal challenge with tissue cysts of a moderately virulent strain, only the brains from mice vaccinated with ROP2 or GRA4 in combination with CpG-ODN showed a significant reduction (63% and 62%, respectively) in their parasite load compared to the controls. The rate of protection obtained with GRA4+ROP2+CpG-ODN resulted equivalent (66%) to those achieved with the single antigens plus CpG-ODN. Taken together, these results indicate that CpG-ODN is an important candidate adjuvant for use in potential multicomponent anti-T. gondii vaccines for animals and humans.

The Contribution of the Transition Zone to the Strength of High Quality Silica Fume Concretes

The strength of high strength silica fume concretes is usually attributed to the reduction in w/c ratio and the refinement of the pore structure. A study of concretes and pastes, with and without silica fume, suggests that the contribution of the silica fume to strength is also the result of the densification of the transition zone. It is argued here that this influence is as important as the one due to the reduction in w/c ratio. It is suggested that the densification of the transition zone is the result of the effect of the silica fume on the nature of the fresh concrete.

Effect of codon optimization and subcellular targeting on Toxoplasma gondii antigen SAG1 expression in tobacco leaves to use in subcutaneous and oral immunization in mice

BACKGROUND

Codon optimization and subcellular targeting were studied with the aim to increase the expression levels of the SAG178-322 antigen of Toxoplasma gondii in tobacco leaves. The expression of the tobacco-optimized and native versions of the SAG1 gene was explored by transient expression from the Agrobacterium tumefaciens binary expression vector, which allows targeting the recombinant protein to the endoplasmic reticulum (ER) and the apoplast. Finally, mice were subcutaneously and orally immunized with leaf extracts-SAG1 and the strategy of prime boost with rSAG1 expressed in Escherichia coli was used to optimize the oral immunization with leaf extracts-SAG1.

RESULTS

Leaves agroinfiltrated with an unmodified SAG1 gene accumulated 5- to 10-fold more than leaves agroinfiltrated with a codon-optimized SAG1 gene. ER localization allowed the accumulation of higher levels of native SAG1. However, no significant differences were observed between the mRNA accumulations of the different versions of SAG1. Subcutaneous immunization with leaf extracts-SAG1 (SAG1) protected mice against an oral challenge with a non-lethal cyst dose, and this effect could be associated with the secretion of significant levels of IFN-gamma. The protection was increased when mice were ID boosted with rSAG1 (SAG1+boost). This group elicited a significant Th1 humoral and cellular immune response characterized by high levels of IFN-gamma. In an oral immunization assay, the SAG1+boost group showed a significantly lower brain cyst burden compared to the rest of the groups.

CONCLUSION

Transient agroinfiltration was useful for the expression of all of the recombinant proteins tested. Our results support the usefulness of endoplasmic reticulum signal peptides in enhancing the production of recombinant proteins meant for use as vaccines. The results showed that this plant-produced protein has potential for use as vaccine and provides a potential means for protecting humans and animals against toxoplasmosis.