Publikation
Drača, D.; Mijatović, S.; Krajnović, T.; Kaluđerović, G. N.; Wessjohann, L. A.; Maksimović-Ivanić, D. Synthetic Tubulysin Derivative, Tubugi-1, Against Invasive Melanoma Cells: The Cell Death Triangle Anticancer Res 39, 5403-5415, (2019) DOI: 10.21873/anticanres.13734
Background/Aim: Tubugi-1 is a more stable and
accessible synthetic counterpart of natural tubulysins. This study aimed
to evaluate its cytotoxic potential against anaplastic human melanoma
cells. Materials and Methods: The viability of A-375 cells was
determined by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium
bromide (MTT) and crystal violet assay. The type of cell death and
proliferative rate were investigated using flow cytometry and
fluorescent microscopy, while the molecular background was evaluated by
western blot. Results: Tubugi-1 reduced the viability of A-375 cells,
inducing massive micronucleation, followed by augmented expression of
inhibitor of nuclear factor-κB and caspase-2, typical of a mitotic
catastrophe. Disturbed proliferation and G2M block with prominent
caspase activity, weakened the expression of B-cell lymphoma 2 and
B-cell lymphoma 2-associated X transient up-regulation, coexisted with
intensive autophagy. Specific inhibition of autophagy by chloroquine
resulted in conversion from mitotic catastrophe to rapid apoptosis.
Conclusion: Multilevel anticancer action of tubugi-1 is extended by
co-application of an autophagy inhibitor, giving a new dimension in
further preclinical advancement of this potential agent.
Publikation
Drača, D.; Mijatović, S.; Krajnović, T.; Pristov, J. B.; Đukić, T.; Kaluđerović, G. N.; Wessjohann, L. A.; Maksimović-Ivanić, D. The synthetic tubulysin derivative, tubugi-1,
improves the innate immune response by macrophage polarization in
addition to its direct cytotoxic effects in a murine melanoma model Exp Cell Res 380, 159-170, (2019) DOI: 10.1016/j.yexcr.2019.04.028
Synthetic tubugis are equally potent but more
stable than their natural forms. Their anticancer potential was
estimated on a solid melanoma in vitro and in vivo. Tubugi-1 induced the
apoptosis in B16 cells accompanied with strong intracellular production
of reactive species, subsequently imposing glutathione and thiol group
depletion. Paradoxically, membrane lipids were excluded from the cascade
of intracellular oxidation, according to malondialdehyde decrease.
Although morphologically apoptosis was typical, externalization of
phosphatidylserine (PS) as an early apoptotic event was not detected.
Even their exposition is pivotal for apoptotic cell eradication, primary
macrophages successfully eliminated PS-deficient tubugi-1 induced
apoptotic cells. The tumor volume in animals exposed to the drug in
therapeutic mode was reduced in comparison to control as well as to
paclitaxel-treated animals. Importantly, macrophages isolated from
tubugi-1 treated animals possessed conserved phagocytic activity and
were functionally and phenotypically recognized as M1. The cytotoxic
effect of tubugi-1 is accomplished through its ability to polarize the
macrophages toward M1, probably by PS independent apoptotic cell
engulfment. The unique potential of tubugi-1 to prime the innate immune
response through the induction of a specific pattern of tumor cell
apoptosis can be of extraordinary importance from fundamental and
applicable aspects.
Publikation
Seixas, N.; Ravanello, B. B.; Morgan, I.; Kaluđerović, G. N.; Wessjohann, L. A. Chlorambucil Conjugated Ugi Dendrimers with PAMAM-NH2 Core and Evaluation of Their Anticancer Activity Pharmaceutics 11, 59, (2019) DOI: 10.3390/pharmaceutics11020059
Herein, a new Ugi multicomponent reaction
strategy is described to enhance activity and solubility of the
chemotherapeutic drug chlorambucil through its conjugation to
poly(amidoamine) (PAMAM-NH2) dendrimers with the simultaneous
introduction of lipidic (i-Pr) and cationic (–NH2) or anionic (–COOH)
groups. Standard viability assays were used to evaluate the anticancer
potential of the water-soluble dendrimers against PC-3 prostate and
HT-29 colon cancer cell lines, as well as non-cancerous mouse NIH3T3
fibroblasts. It could be demonstrated that the anticancer activity
against PC-3 cells was considerably improved when both chlorambucil and
–NH2 (cationic) groups were present on the dendrimer surface (1b).
Additionally, this dendrimer showed activity only against the prostate
cancer cells (PC-3), while it did not affect colon cancer cells and
fibroblasts significantly. The cationic chlorambucil-dendrimer 1b blocks
PC-3 cells in the G2/M phase and induces caspase independent apoptosis.
Publikation
Kufka, R.; Rennert, R.; Kaluđerović, G. N.; Weber, L.; Richter, W.; Wessjohann, L. A. Synthesis of a tubugi-1-toxin conjugate by a
modulizable disulfide linker system with a neuropeptide Y analogue
showing selectivity for hY1R-overexpressing tumor cells Beilstein J Org Chem 15, 96-105, (2019) DOI: 10.3762/bjoc.15.11
Tubugi-1 is a small cytotoxic peptide with
picomolar cytotoxicity. To improve its cancer cell targeting, it was
conjugated using a universal, modular disulfide derivative. This allowed
conjugation to a neuropeptide-Y (NPY)-inspired peptide
[K4(C-βA-),F7,L17,P34]-hNPY, acting as NPY Y1 receptor (hY1R)-targeting
peptide, to form a tubugi-1–SS–NPY disulfide-linked conjugate. The
cytotoxic impacts of the novel tubugi-1–NPY peptide–toxin conjugate, as
well as of free tubugi-1, and tubugi-1 bearing the thiol spacer
(liberated from tubugi-1–NPY conjugate), and native tubulysin A as
reference were investigated by in vitro cell viability and proliferation
screenings. The tumor cell lines HT-29, Colo320 (both colon cancer),
PC-3 (prostate cancer), and in conjunction with RT-qPCR analyses of the
hY1R expression, the cell lines SK-N-MC (Ewing`s sarcoma), MDA-MB-468,
MDA-MB-231 (both breast cancer) and 184B5 (normal breast; chemically
transformed) were investigated. As hoped, the toxicity of tubugi-1 was
masked, with IC50 values decreased by ca. 1,000-fold compared to the
free toxin. Due to intracellular linker cleavage, the cytotoxic potency
of the liberated tubugi-1 that, however, still bears the thiol spacer
(tubugi-1-SH) was restored and up to 10-fold higher compared to the
entire peptide–toxin conjugate. The conjugate shows toxic selectivity to
tumor cell lines overexpressing the hY1R receptor subtype like, e.g.,
the hard to treat triple-negative breast cancer MDA-MB-468 cells.
Publikationen in Druck
Makong, Y. S.; Fotso, G. W.; Mouthe, G. H.; Lenta, B.; Rennert, R.; Sewald, N.; Arnold, N.; Wansi, J. D.; Ngadjui, B. T. Bruceadysentoside A, a new pregnane glycoside and
others secondary metabolites with cytotoxic activity from brucea
antidysenterica J. F. Mill. (simaroubaceae) Nat Prod Res (2019) DOI: 10.1080/14786419.2019.1655024
The chemical investigation of the root barks
leaves and stem barks of Brucea antidysenterica J. F. Mill.
(Simaroubaceae) led to the isolation of a new pregnane glycoside, named
Bruceadysentoside A or 3-O-β-L-arabinopyranosyl-pregn-5-en-20-one (1)
together with seventeen known compounds. Their structures were
established from spectral data, mainly HRESIMS, 1 D and 2 D NMR and by
comparison with literature data. Compounds 1, 2, 5, 6, 8, 10, 12 and 13
were tested in vitro for their effects on the viability of two different
human cancer cell lines, namely prostate PC-3 adenocarcinoma cells and
colorectal HT-29 adenocarcinoma cells. No substantial activities were
recorded for 2, 10, 12 and 13 (up to 10 μM concentration). 1, 5 and 8
did not show strong anti-proliferative effects up to 100 μM, however, 6
exhibited a stronger anti-proliferative effect with IC50 values of ∼
100 μM against PC-3 and ∼ 200 μM against HT-29.
Publikation
Sakna, S. T.; Mocan, A.; Sultani, H. N.; El-fiky, N. M.; Wessjohann, L. A.; Farag, M. A. Metabolites profiling of Ziziphus leaf taxa via UHPLC/PDA/ESI-MS in relation to their biological activities Food Chem 293, 233-246, (2019) DOI: 10.1016/j.foodchem.2019.04.097
Ziziphus plants are well recognized for their
nutritive and medicinal value worldwide, albeit their chemical profile
has yet to be fully reported. The secondary metabolites profile of three
traditionally used Ziziphus leaf accessions was investigated via
ultra-high performance liquid chromatography coupled to photodiode array
and electrospray ionization mass detectors (UHPLC/PDA/ESI-MS). A total
of 102 metabolites were characterized revealing the first holistic
approach onto Ziziphus leaf metabolome and to include the first report
of several novel flavonoids and cyclopeptide alkaloids. Fragmentation
pattern for cyclopeptide alkaloids was proposed via ESI-MS. Principal
component analysis (PCA) revealed close metabolite resemblance among Z.
spina-christi and Z. mauritiana leaf specimens found enriched in
saponins and distinct from that of Z. jujuba in which
quercetin-3-O-(2-pentosyl)-rhamnoside was most abundant. Further,
in-vitro antioxidant, anti-inflammatory and antidiabetic assays revealed
for Z. spina-christi and Z. mauritiana strong effects compared to Z.
jujuba and in correlation with their metabolites repertoire.
Publikation
Pantelić, N. Đ.; Lerbs, M.; Wolf, K.; Wessjohann, L. A.; Kaluđerović, G. N. In vitro anticancer evaluation of novel triphenyltin(IV) compounds with some N-acetyl-S-(naphthoquinone)cysteine derivatives J Serb Chem Soc 84, 1119-1127, (2019) DOI: 10.2298/JSC190322032P
Triphenyltin(IV) compounds with naphthoquinone
derivatives containing N-acetylcysteine,
N-acetyl-S-(1,2-dion-4-naphthyl)cysteine (1,2-NQC), 1, and
N-acetyl-S-(1,4-dion-2-naphthyl)cysteine (1,4-NQC), 2, were synthesized
and characterized by elemental microanalysis, IR, multinuclear (1H, 13C,
119Sn) NMR spectroscopy as well as HR-ESI mass spectrometry. With the
aim of in vitro anticancer activity determination of ligand precursors
and novel synthesized organotin(IV) compounds against human cervix
adenocarcinoma (HeLa), human colon carcinoma (HT-29), and melanoma
carcinoma cell line (B16F10), MTT colorimetric assay method was applied.
The results indicate that synthesized compounds exhibited remarkable
antiproliferative activity toward all tested cell lines with IC50 in the
range of 0.17 to 0.87 μM. Complex 1 showed the greatest activity
against HT-29 cells, with IC50 value of 0.21 ± 0.01 μM, 119 times better
than cisplatin, while complex 2 demonstrated the highest activity
toward HeLa cells, IC50 = 0.17 ± 0.01 μM, which is ~26 times better than
cisplatin.
Publikation
Shaaban, S.; Ashmawy, A. M.; Negm, A.; Wessjohann, L. A. Synthesis and biochemical studies of novel organic
selenides with increased selectivity for hepatocellular carcinoma and
breast adenocarcinoma Eur J Med Chem 179, 515-526, (2019) DOI: 10.1016/j.ejmech.2019.06.075
Nineteen organoselenides were synthesized and
tested for their intrinsic cytotoxicity in hepatocellular carcinoma
(HepG2) and breast adenocarcinoma (MCF-7) cell lines and their
corresponding selective cytotoxicity (SI) was estimated using normal
lung fibroblast (WI-38) cells. Most of the organic selenides exhibited
good anticancer activity, and this was more pronounced in HepG2 cells.
Interestingly, the naphthoquinone- (5), thiazol- (12), and the azo-based
(13) organic selenides demonstrated promising SI (up to 76).
Furthermore, the amine 4c, naphthoquinone 5, and azo-based 13 and 15
organic selenides were able to down-regulate the expression of Bcl-2 and
up-regulate the expression levels of IL-2, IL-6 and CD40 in HepG2 cells
compared to untreated cells. Moreover, most of the synthesized
candidates manifested good free radical-scavenging and GPx-like
activities comparable to vitamin C and ebselen. The obtained results
suggested that some of the presented organoselenium candidates have
promising anti-HepG2 and antioxidant activities.
Publikationen in Druck
Tabassum, N.; Eschen‐Lippold, L.; Athmer, B.; Baruah, M.; Brode, M.; Maldonado‐Bonilla, L. D.; Hoehenwarter, W.; Hause, G.; Scheel, D.; Lee, J. Phosphorylation‐dependent control of an RNA
granule‐localized protein that fine‐tunes defence gene expression at a
post‐transcriptional level Plant J (2019) DOI: 10.1111/tpj.14573
Mitogen‐activated protein kinase (MAPK)
cascades are key signalling modules of plant defence responses to
pathogen‐associated molecular patterns (PAMPs, e.g. bacterial flg22
peptide). The Tandem Zinc Finger Protein 9 (TZF9) is an RNA‐binding
protein that is phosphorylated by two PAMP‐responsive MAPKs, MPK3 and
MPK6. We mapped the major phosphosites in TZF9 and showed their
importance for controlling in vitro RNA‐binding activity, in vivo
flg22‐induced rapid disappearance of TZF9‐labelled processing body‐like
structures and TZF9 protein turnover. Microarray analysis showed a
strong discordance between transcriptome (total mRNA) and translatome
(polysome‐associated mRNA) in the tzf9 mutant, with more mRNAs
associated to ribosomes in the absence of TZF9. This suggests that TZF9
may sequester and inhibit translation of subsets of mRNAs. Fittingly,
TZF9 physically interacts with poly(A)‐binding protein 2 (PAB2), a
hallmark constituent of stress granules – a site for stress‐induced
translational stalling/arrest. TZF9 even promotes stress granule
assembly in the absence of stress. Hence, MAPKs may control defence gene
expression post‐transcriptionally through release from translation
arrest within TZF9‐PAB2‐containing RNA granules or perturbing PAB2
functions in translation control (e.g. in the mRNA closed‐loop model of
translation).
Publikation
Mijatović, S.; Bramanti, A.; Nicoletti, F.; Fagone, P.; Kaluđerović, G. N.; Maksimović-Ivanić, D. Naturally occurring compounds in differentiation based therapy of cancer Biotechnol Adv 36, 1622-1632, (2018) DOI: 10.1016/j.biotechadv.2018.04.001
Differentiation of cancer cells entails the
reversion of phenotype from malignant to the original. The conversion to
cell type characteristic for another tissue is named
transdifferentiation. Differentiation/transdifferentiation of malignant
cells in high grade tumor mass could serve as a nonaggressive approach
that potentially limits tumor progression and augments chemosensitivity.
While this therapeutic strategy is already being used for treatment of
hematological cancers, its feasibility for solid malignancies is still
debated. We will presently discuss the natural compounds that show these
properties, with focus on anthraquinones from Aloe vera, Senna, Rheum
sp. and hop derived prenylflavonoids.