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Background: Despite a multimodal approach including surgery, chemo- and radiotherapy, the 5-year event-free survival rate for rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in childhood, remains very poor for metastatic patients, mainly due to the selection and proliferation of tumour cells driving resistance mechanisms. Personalised medicine-based protocols using new drugs or targeted therapies in combination with conventional treatments have the potential to enhance the therapeutic effects, while minimizing damage to healthy tissues in a wide range of human malignancies, with several clinical trials being started. In this study, we analysed, for the first time, the antitumour activity of SFX-01, a complex of synthetic d, l-sulforaphane stabilised in alpha-cyclodextrin (Evgen Pharma plc, UK), used as single agent and in combination with irradiation, in four preclinical models of alveolar and embryonal RMS. Indeed, SFX-01 has shown promise in preclinical studies for its ability to modulate cellular pathways involved in inflammation and oxidative stress that are essential to be controlled in cancer treatment., Methods: RH30, RH4 (alveolar RMS), RD and JR1 (embryonal RMS) cell lines as well as mouse xenograft models of RMS were used to evaluate the biological and molecular effects induced by SFX-01 treatment. Flow cytometry and the modulation of key markers analysed by q-PCR and Western blot were used to assess cell proliferation, apoptosis, autophagy and production of intracellular reactive oxygen species (ROS) in RMS cells exposed to SFX-01. The ability to migrate and invade was also investigated with specific assays. The possible synergistic effects between SFX-01 and ionising radiation (IR) was studied in both the in vitro and in vivo studies. Student's t-test or two-way ANOVA were used to test the statistical significance of two or more comparisons, respectively., Results: SFX-01 treatment exhibited cytostatic and cytotoxic effects, mediated by G2 cell cycle arrest, apoptosis induction and suppression of autophagy. Moreover, SFX-01 was able to inhibit the formation and the proliferation of 3D tumorspheres as monotherapy and in combination with IR. Finally, SFX-01, when orally administered as single agent, displayed a pattern of efficacy at reducing the growth of tumour masses in RMS xenograft mouse models; when combined with a radiotherapy regime, it was observed to act synergistically, resulting in a more positive outcome than would be expected by adding each exposure alone., Conclusions: In summary, our results provide evidence for the antitumour properties of SFX-01 in preclinical models of RMS tumours, both as a standalone treatment and in combination with irradiation. These forthcoming findings are crucial for deeper investigations of SFX-01 molecular mechanisms against RMS and for setting up clinical trials in RMS patients in order to use the SFX-01/IR co-treatment as a promising therapeutic approach, particularly in the clinical management of aggressive RMS disease., (© 2024. The Author(s).)

The high affinity nerve growth factor (NGF) NGF receptor, p75NTR, is a member of the tumor necrosis factor (TNF) receptor superfamily that shares a conserved intracellular death domain capable of inducing apoptosis and suppressing growth in prostate epithelial cells. Expression of this receptor is lost as prostate cancer progresses and is minimal in established prostate cancer cell lines. We aimed to verify the role of p75NTR in the azacitidine-mediated antitumor effects on 22Rv1 and PC3 androgen-independent prostate cancer cells. In the present study, we reported that the antiproliferative and pro-apoptotic effects of 5-azacytidine (azacitidine) were more marked in the presence of physiological concentrations of NGF and were reduced when a blocking p75NTR antibody or the selective p75NTR inhibitor, Ro 08-2750, were used. Azacitidine increased the expression of p75NTR without interfering with the expression of the low affinity NGF receptor TrkA and induced caspase 9-dependent caspase 3 activity. Taken together, our results suggest that the NGF network could be a candidate for future pharmacological manipulation in aggressive prostate cancer.

In this study, we investigated the antiproliferative effects of saffron extract (SE) and its major constituent crocin on 5 different malignant and 2 nonmalignant prostate cancer cell lines. Using high performance liquid chromatography (HPLC), the purity and content of crocin were determined. All cells were incubated with different concentrations of SE or crocin for 48 h. Cell cycle and apoptosis were also evaluated. In a time- and concentration-dependent manner, both SE and crocin reduced cell proliferation in all malignant cell lines with IC50 values ranging between 0.4 and 4 mg/ml for SE and between 0.26 and 0.95 mM/ml for crocin. Nonmalignant cells were not affected. Flow cytometry profiles revealed that most cells were arrested at G0/G1 phase with a significant presence of apoptotic cells. Western blot analysis revealed that the expression of Bcl-2 was strikingly downregulated, whereas Bax was upregulated. Analysis of caspase activity indicated a caspase-dependent pathway with involvement of caspase-9 activation, suggesting an intrinsic pathway. Based on these findings, it can be concluded that both SE and crocin can inhibit cell proliferation, arrest cell cycle progression, inducing apoptosis in prostate cancer. Consequently, these agents could potentially be used as a chemopreventive as well as a chemotherapeutic agent for prostate cancer management.

One of the major obstacles in the treatment of hormone-refractory prostate cancer (HRPC) is the development of chemoresistant tumors. The aim of this study is to evaluate the role of azacitidine as chemosensitizing agent in association with docetaxel (DTX) and cisplatin using two models of aggressive prostate cancer, the 22rv1, and PC3 cell lines. Azacitidine shows antiproliferative effects associated with increased proportion of cells in G0/G1 and evident apoptosis in 22rv1 cells and increased proportion of cells in G2/M phase with the absence of acute cell killing in PC3 cells. In vivo, azacitidine (0.8 mg/kg i.p.) reduced tumor proliferation and induced apoptosis in both xenografts upmodulating the expression of p16INKA, Bax, Bak, p21/WAF1, and p27/KIP1, and inhibiting the activation of Akt activity and the expression of cyclin D1, Bcl-2, and Bcl-XL. In vitro treatments with azacitidine lead to upregulation of cleaved caspase 3 and PARP. BCl2 antagonists, such as HA-14-1, enhanced the effects of azacitidine in these two prostate cancer models. In addition, azacitidine showed synergistic effects with both DTX and cisplatin. In vivo this agent caused tumor growth delay without complete regression in xenograft systems. Azacitidine sensitized PC3 and 22rv1 xenografts to DTX and cisplatin treatments. These combinations were also tolerable in mice and superior to either agent alone. As DTX is the standard first-line chemotherapy for HRPC, the development of DTX-based combination therapies is of great interest in this disease stage. Our results provide a rationale for clinical trials on combination treatments with azacitidine in patients with hormone-refractory and chemoresistant prostate tumors.

Deer antlers are the fastest growing tissue. Because they are based on proto-oncogenes, to avoid the risk of cancer, antlers evolved strong anticancer mechanisms, and thus their extract (DVA) is effective also against the few human tumours studied so far. We assessed whether DVA is a general anticancer compound by testing the direct effects in cells of different tumours: glioblastoma (GBM; lines U87MG and U251), colorectal (CRC; lines DLD-1, HT-29, SW480, and SW620), breast cancer (BRCA; lines MCF7, SKBR3, and PA00), and leukaemia (THP-1). DVA reduced the viability of tumours but not healthy cells (NHC; lines 293T and HaCaT). Mobility decreased at least for the longest test (72 h). Intraperitoneal/oral 200 mg DVA/kg administration in GBM xenograft mice for 28 d reduced tumour weight by 66.3% and 61.4% respectively, and it also reduced spleen weight (43.8%). In addition, tumours treated with DVA showed symptoms of liquefactive necrosis. Serum cytokines showed DVA up-regulated factors related to tumour fighting and down-regulated those related to inducing immune tolerance to the tumour. DVA shows general anticancer effects in the lines tested and, in GBM mice, also strong indirect effects apparently mediated by the immune system. DVA may contain a future anticancer medicine without secondary effects. [ABSTRACT FROM AUTHOR]

Glioblastoma is the most frequent and the most lethal primary brain tumor among adults. Standard of care is the association of radiotherapy with concomitant or adjuvant temozolomide. However, to date, recurrence is inevitable. The CXCL12/CXCR4 pathway is upregulated in the glioblastoma tumor microenvironment regulating tumor cell proliferation, local invasion, angiogenesis, and the efficacy of radio-chemotherapy. In this study, we evaluated the effects of the novel CXCR4 antagonist, PRX177561, in preclinical models of glioblastoma. CXCR4 expression and PRX177561 effects were assessed on a panel of 12 human glioblastoma cells lines and 5 patient-derived glioblastoma stem cell cultures. Next, the effect of PRX177561 was tested in vivo, using subcutaneous injection of U87MG, U251, and T98G cells as well as orthotopic intrabrain inoculation of luciferase-transfected U87MG cells. Here we found that PRX177561 impairs the proliferation of human glioblastoma cell lines, increases apoptosis, and reduces CXCR4 expression and cell migration in response to stromal cell-derived factor 1alpha in vitro. PRX177561 reduced the expression of stem cell markers and increased that of E-cadherin and glial fibrillary acidic protein in U87MG cells consistent with a reduction in cancer stem cells. In vivo, PRX177561 reduced the weight and increased the time to progression of glioblastoma subcutaneous tumors while increasing disease-free survival and overall survival of mice bearing orthotopic tumors. Our findings suggest that targeting stromal cell-derived factor 1 alpha/CXCR4 axis by PRX177561 might represent a novel therapeutic approach against glioblastoma and support further investigation of this compound in more complex preclinical settings in order to determine its therapeutic potential. [ABSTRACT FROM AUTHOR]

Shuttling of specific proteins out of the nucleus is essential for the regulation of the cell cycle and proliferation of both normal and malignant tissues. Dysregulation of this fundamental process may affect many other important cellular processes such as tumor growth, inflammatory response, cell cycle, and apoptosis. It is known that XPO1 (Exportin- 1/Chromosome Region Maintenance 1/CRM1) is the main mediator of nuclear export in many cell types. Nuclear proteins exported to the cytoplasm by XPO1 include the drug targets topoisomerase IIalpha (topo IIalpha) and BCR-ABL and tumor suppressor proteins such as Rb, APC, p53, p21, and p27. XPO1 can mediate cell proliferation through several pathways: (i) the sub-cellular localization of NES-containing oncogenes and tumor suppressor proteins, (ii) the control of the mitotic apparatus and chromosome segregation, and (iii) the maintenance of nuclear and chromosomal structures. The XPO1 protein is elevated in ovarian carcinoma, glioma, osteosarcoma, pancreatic and cervical cancer. There is a growing body of research indicating that XPO1may have an important role as a prognostic marker in solid tumors. Because of this, nuclear export inhibition through XPO1 is a potential target for therapeutic intervention in many cancers. The best understood XPO1 inhibitors are the small molecule nuclear export inhibitors (NEIs; Leptomycin B and derivatives, ratjadones, PKF050-638, valtrate, ACA, CBS9106, selinexor/KPT-330, and verdinexor/KPT- 335). Selinexor and verdinexor are orally bioavailable, highly potent, small molecules that are classified as Selective Inhibitors of Nuclear Export (SINE). KPT-330 is the only NEI currently in Phase I/II human clinical trials in hematological and solid cancers. Of all the potential targets in nuclear cytoplasmic transport, the nuclear export receptorXPO1 remains the best understood and most advanced therapeutic target for the treatment of cancer. [ABSTRACT FROM AUTHOR]

One of the major obstacles in the treatment of hormone-refractory prostate cancer (HRPC) is the development of chemo-resistant tumors. The aim of this study is to evaluate the role of Palomid 529 (P529), a novelTORC1/TORC2 inhibitor, in association with docetaxel (DTX) and cisplatin (CP). This work utilizes a wide panel of prostatic cancer cell lines with or without basal activation of Akt as well as two in vivo models of aggressive HRPC. The blockade of Akt/mTOR activity was associated to reduced cell proliferation and induction of apoptosis. Comparison of IC50 values calculated for PTEN-positive and PTEN-negative cell lines as well as the PTEN transfection in PC3 cells or PTEN silencing in DU145 cells revealed that absence of PTEN was indicative for a better activity of the drug. In addition, P529 synergized with DTX and CP. The strongest synergism was achieved when prostate cancer (PCa) cells were sequentially exposed to CP or DTX followed by treatment with P529. Treatment with P529 before the exposure to chemotherapeutic drugs resulted in a moderate synergism, whereas intermediated values of combination index were found when drugs were administered simultaneously. In vivo treatment of a combination of P529 with DTX or CP increased the percentage of complete responses and reduced the number of mice with tumor progression. Our results provide a rationale for combinatorial treatment using conventional chemotherapy and a Akt/mTOR inhibitor as promising therapeutic approach for the treatment of HRPC, a disease largely resistant to conventional therapies. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of MK906, a selective 5 alpha reductase (5αR) type 2 (5αR2) inhibitor, and of MK386, a specific 5αR1 inhibitor, on the cellular proliferation of androgen-dependent human prostatic cancer (PCa) cells in cultures of cells derived from bioptic and surgical tissues. Methods: In this study we tested the effects of MK906 and MK386 in 30 cultures derived from PCa, 6 from PIN and 10 from benign prostatic hyperplasia specimens. Results: Prostate primary cultures under short-term conditions (with <4 subcultures) represent a mixture of epithelial and stromal cells. Epithelial cells require testosterone (T) for optimal growth, but were not able to grow in the presence of T under long-term conditions even if DHT was able to induce cellular proliferation to a similar extent in both conditions, suggesting that 5αR can be lost in longterm cultures. Therefore, our studies were performed under short-term conditions. Both 5αR inhibitors decreased cell proliferation significantly and dose-dependently in all the samples tested. MK906 was more efficient than MK386 in 7 out of 10 cultures derived from BPH tissues, in 4 out of 6 cultures derived from PIN and in 18 out of 30 cultures derived from PCa. In 3 out of 10 BPH, in 2 out of 6 PIN and in 5 out of 30 PCaderived cultures, both inhibitors presented similar efficacy, whereas in 1 out of 10 BPH and 7 out of 30 PCaderived cultures MK386 was more efficient than MK906. In addition, MK386 was more efficient than MK906 in 4 out of 15 non-metastatic PCa and 2 out of 7 metastatic PCa-derived cultures. Conclusions: Considering that 5αR1 (responsible primarily for androgenic catabolism) is mostly expressed in epithelial cells and that 5αR2 (responsible for local DHT synthesis and release) is expressed in the stromal cells (which provides several paracrine growth factors and DHT itself to the epithelial cells), our experiments suggest that the inhibition of both 5αR1 and 5αaR2 by MK386 and MK906, respectively, may have therapeutic potential in order to reduce the growth and progression of human prostatic cancers, through the inhibition of autocrine or paracrine mechanisms involving the stromal cell compartment. In addition, some effects of 5αR inhibitors could be mediated by estrogens, which are synthesized by the aromatase enzyme present in the epithelial cells. These aspects could be considered in order to improve the therapeutical management of PCa and for future clinical trials. [ABSTRACT FROM AUTHOR]

Simple Summary: In the last ten years, the human helicase protein DDX3X turned out to be an extremely interesting target for the development of potential anticancer drugs. Herein, we discovered BA103, a novel specific inhibitor of the helicase binding site of DDX3X, which is characterized by broad-spectrum anticancer activity. BA103 revealed promising tolerability in fibroblasts and good pharmacokinetic properties. Furthermore, BA103 was able to decrease the expression of β-catenin and to reduce tumor migration. Its capability to pass the blood–brain barrier led us to investigate its potential against glioblastoma, which is a high refractory disease with poor prognosis. High efficacy was proven in both xenograft and orthotopic animal models. DDX3X is an ATP-dependent RNA helicase that has recently attracted interest for its involvement in viral replication and oncogenic progression. Starting from hit compounds previously identified by our group, we have designed and synthesized a new series of DDX3X inhibitors that effectively blocked its helicase activity. These new compounds were able to inhibit the proliferation of cell lines from different cancer types, also in DDX3X low-expressing cancer cell lines. According to the absorption, distribution, metabolism, elimination properties, and antitumoral activity, compound BA103 was chosen to be further investigated in glioblastoma models. BA103 determined a significant reduction in the proliferation and migration of U87 and U251 cells, downregulating the oncogenic protein β-catenin. An in vivo evaluation demonstrated that BA103 was able to reach the brain and reduce the tumor growth in xenograft and orthotopic models without evident side effects. This study represents the first demonstration that DDX3X-targeted small molecules are feasible and promising drugs also in glioblastoma. [ABSTRACT FROM AUTHOR]