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BioRxiv : the Preprint Server For... Jun 2024The keratin cytoskeleton and associated desmosomes contribute to the mechanical stability of epithelial tissues, but their organization in bladder umbrella cells and...
The keratin cytoskeleton and associated desmosomes contribute to the mechanical stability of epithelial tissues, but their organization in bladder umbrella cells and their responses to bladder filling are poorly understood. Using super-resolution confocal microscopy, along with 3D image reconstruction and platinum replica electron microscopy, we observed that the apical keratin network of umbrella cells was organized as a dense tile-like mesh comprised of tesserae bordered on their edges by cortical actin filaments, filled with woven keratin filaments, and crosslinked by plectin. A band of keratin was also observed at the cell periphery that was linked to the junction-associated actin ring by plectin. During bladder filling, the junction-localized desmosomal necklace expanded, and a subjacent girded layer was formed that linked the keratin network to desmosomes, including those at the umbrella cell-intermediate cell interface. Disruption of plectin led to focal keratin network dissolution, loss of the junction-associated band of keratin, perturbation of tight junction continuity, and loss of cell-cell cohesion. Our studies reveal a novel tile-like organization of the umbrella cell keratin cytoskeleton that is dependent on plectin, that reorganizes in response to bladder filling, and that likely serves to maintain umbrella cell continuity in the face of mechanical distension.
PubMed: 38915686
DOI: 10.1101/2024.06.11.598498 -
BioRxiv : the Preprint Server For... Jun 2024Ovarian cancer is a deadly female cancer with high rates of recurrence. The primary treatment strategy for patients is platinum-based therapy regimens that almost...
Ovarian cancer is a deadly female cancer with high rates of recurrence. The primary treatment strategy for patients is platinum-based therapy regimens that almost universally develop resistance. Consequently, new therapeutic avenues are needed to overcome the plateau that current therapies have on patient outcomes. We describe a gene amplification involving both HSF1 and MYC, wherein these two genes on chromosome 8q are co-amplified in over 7% of human tumors that is enriched to over 30% of patients with ovarian cancer. We further found that HSF1 and MYC transcriptional activity is correlated in human tumors and ovarian cancer cell lines, suggesting they may cooperate in ovarian cancer cells. CUT&RUN for HSF1 and MYC in co-amplified ovarian cancer cells revealed that HSF1 and MYC have overlapping binding at a substantial number of locations throughout the genome where their binding peaks are near identical. Consistent with these data, a protein-protein interaction between HSF1 and MYC was detected in ovarian cancer cells, implying these two transcription factors have a molecular cooperation. Further supporting their cooperation, growth of HSF1-MYC co-amplified ovarian cancer cells were found to be dependent on both HSF1 and MYC. In an attempt to identify a therapeutic target that could take advantage of this dependency on both HSF1 and MYC, PLK1 was identified as being correlated with HSF1 and MYC in primary human tumor specimens, consistent with a previously established effect of PLK1 on HSF1 and MYC protein levels. Targeting PLK1 with the compound volasertib (BI-6727) revealed a greater than 200-fold increased potency of volasertib in HSF1-MYC co-amplified ovarian cancer cells compared to ovarian cancer cells wild-type HSF1 and MYC copy number, which extended to several growth assays, including spheroid growth. Volasertib, and other PLK1 inhibitors, have not shown great success in clinical trials and this study suggests that targeting PLK1 may be viable in a precision medicine approach using HSF1-MYC co-amplification as a biomarker for response.
PubMed: 38915574
DOI: 10.1101/2024.06.11.598486 -
Frontiers in Oncology 2024In the setting of metastatic adrenocortical cancer, there are limited therapy options such as mitotane and platinum-based chemotherapy with only low response rates....
In the setting of metastatic adrenocortical cancer, there are limited therapy options such as mitotane and platinum-based chemotherapy with only low response rates. Ipilimumab and nivolumab are approved for several solid cancer types. Tumor mutational burden is one established marker to predict treatment success of immunotherapy and has been associated with improved response rates to immune checkpoint inhibitors. We here present the case of a 68-year-old woman with metastatic adrenocortical cancer and high tumor mutational burden treated with ipilimumab and nivolumab in a fourth-line setting. She showed a stable disease for at least 48 weeks, which is significantly longer than the treatment response to mitotane or platinum-based chemotherapy. To the best of our knowledge, this is the first successful use of a long-term two-drug immunotherapy (48 weeks) in a patient with metastatic adrenocortical cancer and high mutational burden. Ipilimumab and nivolumab should be considered as a new therapy option in this patient group.
PubMed: 38915369
DOI: 10.3389/fonc.2024.1406616 -
Frontiers in Oncology 2024Homologous recombination (HR) comprises series of interrelated pathways that repair double-stranded DNA breaks and inter-strand crosslinks. It provides support for DNA...
The prognostic and predictive value of homologous recombination deficiency status in patients with advanced stage epithelial ovarian carcinoma after first-line platinum-based chemotherapy.
OBJECTIVE
Homologous recombination (HR) comprises series of interrelated pathways that repair double-stranded DNA breaks and inter-strand crosslinks. It provides support for DNA replication to recover stalled or broken replication forks. Compared with homologous recombination proficiency (HRP), cancers with homologous recombination deficiency (HRD) are more likely to undergo cell death when treated with DNA-damaging agents, such as platinum agents, and have better disease control.
METHODS
Patients diagnosed with stage III/IV ovarian cancer, early stages with recurrence, who received adjuvant chemotherapy after debulking surgery, and who also had known HR status were eligible.
RESULTS
Forty-four patients were included, with 21 in the HRD group (including 8 with germline mutations) and 23 in the HRP group. The HRD group was composed predominantly of serous carcinoma (95.2%), while mucinous (n=3) and clear cell (n=1) cases were all found in the HRP group. Stage III/IV disease was 66.7% and 91.3% in HRD and HRP groups, respectively (p=0.064). Patients who were optimally debulked to no residual disease was 90.0% and 72.7% (p=0.243), respectively. Late line use of PARP inhibitors was 33.3% and 17.4% (p=0.303). Median PFS was 22.5 months (95% CI, 18.5 - 66.6) and 21.5 months (95% CI, 18.3-39.5) (p=0.49) in HRD and HRP respectively. Median platinum free interval (PFI) was 15.8 months (95% CI 12.4-60.4) and 15.9 months (95% CI 8.3-34.1) (p=0.24), respectively. Median OS was 88.2 months (95% CI 71.2-NA) and 49.7 months (95% CI 35.1-NA) (p=0.21). The PFS of the patients with germline mutations (n=5) was 54.3 months (95% CI 23.1-NA) and 21.5 months (95% CI 18.3-39.5) in the HRP group (p=0.095); the PFI difference was 47.7 months (95% CI 17.6-NA) in the mutation group, and 15.9 months (95% CI 12.4-60.4) in HRP, showing statistical significance (p=0.039); while the median OS was NA and 49.7 months (95% CI 35.1-NA) respectively (p=0.051). When adding two additional patients with somatic mutations to the germline mutation carriers, the median OS is NA (95% CI 73, NA) versus 49.7 months (95% CI 35.1, NA) for HRP (p=0.045).
CONCLUSIONS
HRD status was not associated with longer PFS or PFI in advanced ovarian cancer who received first line adjuvant platinum-based chemotherapy. Its role as a prognostic marker for overall survival is suggested, particularly in the subgroup with germline and somatic mutations.
PubMed: 38915363
DOI: 10.3389/fonc.2024.1372482 -
ACS Omega Jun 2024In the present paper, the effects of metal promoters (M = Fe, Co, and Cu) in Pt/M Zr O catalysts and the influence of CO and HO on the CO oxidation activity (PROX)...
Effects of Metal Promoters (M = Fe, Co, and Cu) in Pt/M Zr O Catalysts and Influence of CO and HO on the CO Oxidation Activity (PROX): Analysis of Surface Properties After Reaction.
In the present paper, the effects of metal promoters (M = Fe, Co, and Cu) in Pt/M Zr O catalysts and the influence of CO and HO on the CO oxidation activity (PROX) were investigated. To do that, characterizations of catalyst structures and surfaces were performed and reported here. The catalyst Pt/Fe Zr O (PFeZ) was the most active at low temperatures among the analyzed ones. The addition of platinum caused strong interaction with the mixed oxide, affecting the structure and the surface composition, blocking basic sites, and thus preventing catalyst deactivation. Particularly, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) results evidenced the formation of carboxylate and carbonate species. Besides, the addition of CO and HO in the gas feed stream affected the observed CO oxidation results, showing that CO competes with O on metallic sites. Moreover, DRIFTS and temperature-programmed desorption (TPD) analyses suggested the occurrence of OH oxidation by CO, leading to the formation of highly reactive compounds that can be easily oxidized.
PubMed: 38911746
DOI: 10.1021/acsomega.3c09039 -
Hepatobiliary Surgery and Nutrition Jun 2024
PubMed: 38911196
DOI: 10.21037/hbsn-24-140 -
Oncology Letters Aug 2024Bevacizumab plus platinum-based chemotherapy provides modest benefits in non-squamous non-small cell lung cancer (NSCLC), while its application as a neoadjuvant regimen...
Efficacy and safety of bevacizumab and platinum‑based chemotherapy as neoadjuvant regimen for stage‑IIIA non‑squamous non‑small cell lung cancer: A retrospective study.
Bevacizumab plus platinum-based chemotherapy provides modest benefits in non-squamous non-small cell lung cancer (NSCLC), while its application as a neoadjuvant regimen has yet to be validated. The present study aimed to assess the efficacy of neoadjuvant bevacizumab plus platinum-based chemotherapy in patients with stage-IIIA non-squamous NSCLC. Data from 110 patients with stage-IIIA non-squamous NSCLC with negative driver genes, who received neoadjuvant bevacizumab plus platinum-based chemotherapy (n=50) or neoadjuvant platinum-based chemotherapy alone (n=60), and tumor resection, were retrospectively reviewed in the current study. In addition, the data on pathological response, disease-free survival (DFS), overall survival (OS) and adverse events were obtained. The results demonstrated that neoadjuvant bevacizumab plus chemotherapy did not significantly increase the pathological complete response (pCR) rate in comparison with neoadjuvant chemotherapy alone (18.0 vs. 8.3%; P=0.130). However, neoadjuvant bevacizumab plus chemotherapy significantly increased the rates of DFS (P=0.007) and OS (P=0.049) compared with neoadjuvant chemotherapy alone. Adjustments were then performed using multivariate logistic or Cox regression analyses, which demonstrated that neoadjuvant bevacizumab plus chemotherapy in comparison with neoadjuvant chemotherapy alone only significantly independently prolonged DFS [hazard ratio (HR)=0.251; P=0.042], but did not significantly affect pCR (odds ratio=2.897; P=0.117) or OS (HR=0.297; P=0.158). Furthermore, no significant differences were demonstrated between the number of adverse events in patients receiving neoadjuvant bevacizumab plus chemotherapy in comparison with those receiving neoadjuvant chemotherapy alone (all P>0.05). In conclusion, neoadjuvant bevacizumab plus platinum-based chemotherapy was only associated with a significant improvement in the rate of DFS, but showed limited efficacy in improving pCR and OS rates in comparison with neoadjuvant chemotherapy alone in patients with stage-IIIA non-squamous NSCLC. Therefore, a larger sample size and randomized controlled studies are needed for further validation of the findings of the present study.
PubMed: 38910904
DOI: 10.3892/ol.2024.14508 -
Cureus May 2024Triple-negative breast cancer poses distinct challenges because it lacks hormone receptors and does not have human epidermal growth factor receptor 2 (HER2)...
Triple-negative breast cancer poses distinct challenges because it lacks hormone receptors and does not have human epidermal growth factor receptor 2 (HER2) amplification. Mutations in BRCA1/2 genes are associated with homologous recombination deficiency tumors, rendering them susceptible to poly (ADP-ribose) polymerase (PARP) inhibitors. Notably, germline BRCA1/2 mutations are linked to distinct clinical features, including an increased risk of triple-negative breast cancer (TNBC) and a younger age of onset. PARP inhibitors such as olaparib and talazoparib have demonstrated efficacy in patients with BRCA mutations, leading to FDA approvals for ovarian and breast cancers. However, there remains limited data on PARP inhibitor response rates in patients with somatic BRCA mutations. This case series demonstrates the use of rucaparib in metastatic breast cancer patients harboring both germline and somatic BRCA1/2 mutations, discussing the advancing landscape of targeted therapies in breast cancer management. In the first case, despite undergoing anthracycline-based chemotherapy followed by hormonal therapy, disease progression ensued. However, transitioning to rucaparib yielded a remarkable complete response lasting over two years, highlighting its efficacy in this clinical setting. Similarly, in the second case, rucaparib demonstrated effectiveness as a maintenance therapy subsequent to achieving a near-complete response to taxane and platinum-based treatment. These findings emphasize the promising role of rucaparib in managing metastatic breast cancer in patients with BRCA1/2 mutations, further contributing to the expanding armamentarium of targeted therapies in breast cancer care.
PubMed: 38910707
DOI: 10.7759/cureus.60963 -
Journal of Experimental & Clinical... Jun 2024
PubMed: 38907260
DOI: 10.1186/s13046-024-03102-y -
Science Advances Jun 2024For decades, there has been debate surrounding the transport of dense metal-rich sulfide liquid in mafic magmas. This topic is crucial to understanding the genesis of...
For decades, there has been debate surrounding the transport of dense metal-rich sulfide liquid in mafic magmas. This topic is crucial to understanding the genesis of valuable resources of nickel, copper, and platinum-group elements, which are essential for a sustainable, emission-free energy future. Recent studies of mineralized mafic magmas suggested that gas bubbles adhere to sulfide globules, reducing their density and favoring upward transport. While this hypothesis may explain sulfide mobility in near-surface magmatic environments, it is at odds with key mineralogic and textural observations and does not explain how long-distance sulfide transport operates. Here, we suggest an alternative hypothesis that builds on previous observations, focusing on the interaction between carbonate melt and sulfide liquid. We demonstrate experimentally that carbonate melt wraps sulfide globules forming a relatively mobile pair that may mediate metal-rich sulfide transport from mantle to crust.
PubMed: 38905350
DOI: 10.1126/sciadv.adl3127