Induction of cell cycle arrest by increasing GTP‑RhoA levels via Taxol‑induced microtubule polymerization in renal cell carcinoma

Dynamic molecular responses of the sea urchin Strongylocentrotus intermedius to pathogen infection: Insights from a serial comparative transcriptome analysis

To explore the dynamic molecular responses to pathogen infection in sea urchins, the sea urchin Strongylocentrotus intermedius were infected by a causative pathogen strain of sea urchin black peristomial membrane disease. Specimens were collected at 0, 6, 12, 24, 48, 72, and 96 h post-infection (hpi), and comparative transcriptome analysis were performed. The results showed that 1) a total of 771, 1437, 3477, 8417, 1566, and 2171 differentially expressed genes (DEGs) were identified at 6, 12, 24, 48, 72, and 96 hpi compared with the 0 hpi (as the control), respectively. 2) The number of upregulated DEGs was higher than that of downregulated DEGs at each time point after infection. The largest number of DEGs was obtained at 48 hpi. 3) Among identified DEGs, percent cellular process, binding, and metabolic process related DEGs account for 57.9 %, 49.9 %, and 45.5 %, respectively. Main Rho-GTPase family members (RhoA, Rac1, and Cdc42) exhibited a general upregulated expression trend during the examined infection process, the same as Caspase family members (Casp3, Casp6 and Casp7). 4) Cell cycle and apoptosis pathways are the most affected pathways, the DEG enrichment level of which remained in the top 30 (cell cycle pathways) and top 50 (apoptosis pathways) throughout the whole examined infection process. To sum up, all findings from this study will not only deepen our understanding of the dynamic molecular expression mechanisms of sea urchins in response to pathogen infection, but also provide new clues for elutriating the profound mechanisms of serial gene expression in innate immunity.

Optical blood-brain-tumor barrier modulation expands therapeutic options for glioblastoma treatment

The treatment of glioblastoma has limited clinical progress over the past decade, partly due to the lack of effective drug delivery strategies across the blood-brain-tumor barrier. Moreover, discrepancies between preclinical and clinical outcomes demand a reliable translational platform that can precisely recapitulate the characteristics of human glioblastoma. Here we analyze the intratumoral blood-brain-tumor barrier heterogeneity in human glioblastoma and characterize two genetically engineered models in female mice that recapitulate two important glioma phenotypes, including the diffusely infiltrative tumor margin and angiogenic core. We show that pulsed laser excitation of vascular-targeted gold nanoparticles non-invasively and reversibly modulates the blood-brain-tumor barrier permeability (optoBBTB) and enhances the delivery of paclitaxel in these two models. The treatment reduces the tumor volume by 6 and 2.4-fold and prolongs the survival by 50% and 33%, respectively. Since paclitaxel does not penetrate the blood-brain-tumor barrier and is abandoned for glioblastoma treatment following its failure in early-phase clinical trials, our results raise the possibility of reevaluating a number of potent anticancer drugs by combining them with strategies to increase blood-brain-tumor barrier permeability. Our study reveals that optoBBTB significantly improves therapeutic delivery and has the potential to facilitate future drug evaluation for cancers in the central nervous system.

Successful first-line treatment of simultaneous multiple primary malignancies of lung adenocarcinoma and renal clear cell carcinoma: A case report

Background

Multiple Primary Malignancies (MPMs) refer to the occurrence of two or more primary malignancies in the same organ or multiple organs and tissues of the same patient simultaneously or sequentially, with an incidence rate ranging from 2-17%. According to the difference in the time of occurrence of each primary tumor, MPMs can be classified as simultaneous malignancies and heterochronic malignancies. The former refers to the occurrence of two or more malignancies one after another within 6 months, while the latter refers to the occurrence of two malignancies at an interval of more than 6 months. Currently, there is a lack of effective treatment options for MPMs both nationally and internationally.

Case presentation

The patient was a 65-year-old male smoker with a definite diagnosis of advanced lung adenocarcinoma with kirsten rat sarcoma viral oncogene (KRAS) mutation, concomitant with primary renal clear cell carcinoma (RCCC), who had a progression-free survival (PFS) for 7 months after first-line treatment with albumin-bound paclitaxel and cisplatin in combination with sintilimab.

Conclusion

In this paper, we report a case of advanced lung adenocarcinoma combined with RCCC as a concurrent double primary malignancy, which achieved a satisfactory outcome after first-line chemotherapy combined with immunotherapy, with the aim of exploring effective treatment modalities for this type of MPMs, in order to improve the survival and prognosis of the patient.

Norcantharidin combined with paclitaxel induces endoplasmic reticulum stress mediated apoptotic effect in prostate cancer cells by targeting SIRT7 expression

Prostate cancer (PCa), an extremely common malignancy in males, is the most prevalent disease in several countries. Norcantharidin (NCTD) has antiproliferation, antimetastasis, apoptosis, and autophagy effects in various tumor cells. Nevertheless, the antitumor effect of NCTD combined with paclitaxel (PTX), a chemotherapeutic drug, in PCa remains unknown. The cell growth, proliferative rate, cell cycle distribution, and cell death were determined by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide, colony formation assay, PI staining, and Annexin V/PI staining by flow cytomertry, whereas the mitochondrial membrane potential (MMP) and endoplasmic reticulum (ER) stress was evaluated using the MitoPotential assay and ER-ID red assay. We also evaluated the protein and mRNA expression of SIRTs by Western blotting and qRTPCR assay. Overexpression effectivity was measured by DNA transfection assay. Our study showed that cell viability and proliferative PC3 and DU145 rates were effectively inhibited after NCTD-PTX combination. We also found that NCTD-PTX combination treatment significantly enhance G2/M phase arrest, induction of cell death and ER stress, loss of MMP, and ER- or apoptotic-related protein expression. Furthermore, NCTD-PTX combination treatment was significantly decreasing the protein and mRNA expression of SIRT7 in PCa cells. Combination therapy effectively reduced cell viability, ER stress-mediated apoptosis and p-eIF2α/ATF4/CHOP/cleaved-PARP expression inhibition in SIRT7 overexpression of PCa cells. These results indicate that NCTD combined with PTX induces ER stress-mediated apoptosis of PCa cells by regulating the SIRT7 expression axis. Moreover, combination therapy may become a potential therapeutic strategy against human PCa.

Paclitaxel is effective for controlling astrocyte proliferation in vitro: Implications for generating ventral mesencephalic cultures enriched with dopamine neurons

BACKGROUND

Primary embryonic ventral mesencephalic (VM) cultures are a high throughput tool for understanding and manipulating dopamine neurons, to study the mechanisms that trigger their degeneration during Parkinson's disease (PD), and to test new drugs aimed at treating the disease. Unfortunately, primary cell cultures are often quickly overwhelmed by dividing astrocytes which both obscure neuronal cells and distort the cellular composition that exists in vivo.

NEW METHOD

To develop a new in vitro system whereby astrocyte division can be readily controlled while maintaining neuronal integrity, VM cultures were treated with different doses (1.75, 3.5, 7, 14 nM) of the anti-mitotic drug paclitaxel for up to seven days in vitro. The study subsequently sought to determine the importance of astrocytes in dopamine neuron survival when challenged with an exposure to the toxin 6-hydroxydopamine (6-OHDA).

RESULTS

Optical density (O.D.) measures of GFAP expression and counts of β-III tubulin and tyrosine hydroxylase positive neurons reveals that a low dose of 3.5 nM of paclitaxel significantly reduced the density of GFAP + astrocytes in primary VM cultures, while maintaining the viability of neurons and dopamine neurons. Interestingly, a reduction of GFAP + astrocytes within primary VM cultures did not reveal any statistically significant differences in the number of dopamine neurons surviving treatment with 6-OHDA.

CONCLUSIONS

These findings detail a quick and simple method for stabilising astrocyte numbers in primary VM cultures, without affecting the viability of dopamine neurons, and suggest that astrocytes may not enhance the survival of dopamine neurons when challenged with the 6-OHDA toxin.

Tubulin-Based Nanotubes as Delivery Platform for Microtubule-Targeting Agents

Tubulin-based nanotubes (TNTs) to deliver microtubule-targeting agents (MTAs) for clinical oncology are reported. Three MTAs, docetaxel (DTX), laulimalide (LMD), and monomethyl auristatin E (MMAE), which attach to different binding sites in a tubulin, are loaded onto TNTs and cause structural changes in them, including shape anisotropy and tubulin layering. This drug-driven carrier transformation leads to changes in the drug-loading efficiency and stability characteristics of the carrier. TNTs coloaded with DTX and LMD efficiently deliver dual drug cargoes to cellular tubulins by the endolysosomal pathway, and results in synergistic anticancer and antiangiogenic action of the drugs in vitro. In in vivo tests, TNTs loaded with a microtubule-destabilizing agent MMAE suppress the growth of tumors with much higher efficacy than free MMAE did. This work suggests a new concept of using a drug's target protein as a carrier. The findings demonstrate that the TNTs developed here can be used universally as a delivery platform for many MTAs.