New G-quadruplex-forming oligodeoxynucleotides incorporating a bifunctional double-ended linker (DEL): Effects of del size and ODNs orientation on the topology, stability, and molecularity of del-G-quadruplexes

G-quadruplexes (G4s) are unusual secondary structures of DNA occurring in guanosine-rich oligodeoxynucleotide (ODN) strands that are extensively studied for their relevance to the biological processes in which they are involved. In this study, we report the synthesis of a new kind of G4-forming molecule named double-ended-linker ODN (DEL-ODN), in which two TG4T strands are attached to the two ends of symmetric, non-nucleotide linkers. Four DEL-ODNs differing for the incorporation of either a short or long linker and the directionality of the TG4T strands were synthesized, and their ability to form G4 structures and/or multimeric species was investigated by PAGE, HPLC–size-exclusion chromatography (HPLC–SEC), circular dichroism (CD), and NMR studies in comparison with the previously reported monomeric tetra-ended-linker (TEL) analogues and with the corresponding tetramolecular species (TG4T)4. The structural characterization of DEL-ODNs confirmed the formation of stable, bimolecular DEL-G4s for all DEL-ODNs, as well as of additional DEL-G4 multimers with higher molecular weights, thus suggesting a way towards the obtainment of thermally stable DNA nanostructures based on reticulated DEL-G4s

Spectroscopic and in silico studies on the interaction of substituted pyrazolo[1,2-a]benzo[1,2,3,4]tetrazine-3-one derivatives with c-myc g4-dna

Herein we describe a combined experimental and in silico study of the interaction of a series of pyrazolo[1,2-a]benzo[1,2,3,4]tetrazin-3-one derivatives (PBTs) with parallel G-quadruplex (GQ) DNA aimed at correlating their previously reported anticancer activities and the stabilizing effects observed by us on c-myc oncogene promoter GQ structure. Circular dichroism (CD) melting experiments were performed to characterize the effect of the studied PBTs on the GQ thermal stability. CD measurements indicate that two out of the eight compounds under investigation induced a slight stabilizing effect (2–4 °C) on GQ depending on the nature and position of the substituents. Molecular docking results allowed us to verify the modes of interaction of the ligands with the GQ and estimate the binding affinities. The highest binding affinity was observed for ligands with the experimental melting temperatures (Tms). However, both stabilizing and destabilizing ligands showed similar scores, whilst Molecular Dynamics (MD) simulations, performed across a wide range of temperatures on the GQ in water solution, either unliganded or complexed with two model PBT ligands with the opposite effect on the Tms, consistently confirmed their stabilizing or destabilizing ability ascertained by CD. Clues about a relation between the reported anticancer activity of some PBTs and their ability to stabilize the GQ structure of c-myc emerged from our study. Furthermore, Molecular Dynamics simulations at high temperatures are herein proposed for the first time as a means to verify the stabilizing or destabilizing effect of ligands on the GQ, also disclosing predictive potential in GQ-targeting drug discovery

Lenvatinib for the treatment of renal cell carcinoma

Introduction: Renal cell carcinoma (RCC) accounts for 2\u20133% of all solid tumors. Expression of the receptor for the vascular endothelial growth factor (VEGF) is one of the most common features of RCC. Areas covered: Lenvatinib is a novel multi-kinase inhibitor that has been studied in several solid tumors. It has shown promising results in the treatment of RCC, especially when combined with everolimus, In this review, we summarize the available data of lenvatinib for the treatment of advanced/metastatic renal cell carcinoma. Expert opinion: Lenvatinib in combination with everolimus has provided encouraging results in both clinical and laboratory investigations showing that blocking angiogenesis and the mTOR signalling pathway could be a remarkable approach for treating RCC. As an additive to this type of approach it would be interesting in future clinical settings testing also the combination of lenvatinib and everolimus with immune-therapy

The Emergency Surgery Frailty Index (EmSFI) in Elderly Patients with Acute Appendicitis: An External Validation of Prognostic Score

Background: Identification of reliable risk-stratification tools is critical for surgical decision making, particularly in frail and elderly. The aim of the study is to validate the Emergency Surgery Frailty Index (EmSFI), in over 65 years old patients operated on for acute appendicitis. Methods: An observational study was conducted enrolling elderly patients with diagnosis of acute appendicitis who underwent emergency appendicectomy or right colectomy, between 2016 and 2021. All patients were treated according to the last SIFIPAC/WSES/SICG/SIMEU guidelines. Results: Overall, 61 patients were analyzed. Complication rate was higher for patients in the second EmSFI risk Class. Moreover, ROC analyses identified 3 as the best cutoff value in predicting risk of adverse postoperative events. Complication rate was higher in oldest elderly patients—over 80 years—(42.9 vs 22.5%; p 0.05) and was mainly related to medical complications (42.9 vs 12.5%, p 0.007). However, intestinal obstruction, peri-appendicular abscess on preoperative CT, peritonitis and a longer duration of surgery are related with increased risk of complications in the group of patients under 80 years. Conclusion: The EmSFI score results a valid prognostic marker for frailty status, and it may support the surgeon in emergency setting for acute appendicitis. Patients aged 80 years or older have a higher risk of complications, independent from those factors which relate to increased morbidity in younger elderly patients. Age alone is not a reliable indicator of the real surgical risk, but it must encourage the adoption of multidisciplinary collaborative models of care for this group of patients. © 2023, The Author(s)

Exploring the DNA2-PNA heterotriplex formation in targeting the Bcl-2 gene promoter: A structural insight by physico-chemical and microsecond-scale MD investigation

Peptide Nucleic Acids (PNAs) represent a promising tool for gene modulation in anticancer treatment. The uncharged peptidyl backbone and the resistance to chemical and enzymatic degradation make PNAs highly advantageous to form stable hybrid complexes with complementary DNA and RNA strands, providing higher stability than the corresponding natural analogues. Our and other groups’ research has successfully shown that tailored PNA sequences can effectively downregulate the expression of human oncogenes using antigene, antisense, or anti-miRNA approaches. Specifically, we identified a seven bases-long PNA sequence, complementary to the longer loop of the main G-quadruplex structure formed by the bcl2midG4 promoter sequence, capable of downregulating the expression of the antiapoptotic Bcl-2 protein and enhancing the anticancer activity of an oncolytic adenovirus. Here, we extended the length of the PNA probe with the aim of including the double-stranded Bcl-2 promoter among the targets of the PNA probe. Our investigation primarily focused on the structural aspects of the resulting DNA2-PNA heterotriplex that were determined by employing conventional and accelerated microsecond-scale molecular dynamics simulations and chemical-physical analysis. Additionally, we conducted preliminary biological experiments using cytotoxicity assays on human A549 and MDA-MB-436 adenocarcinoma cell lines, employing the oncolytic adenovirus delivery strategy

GOLFIG Chemo-Immunotherapy in Metastatic Colorectal Cancer Patients. A Critical Review on a Long-Lasting Follow-Up

Background: GOLFIG is a chemo-immunotherapy regimen established in preclinical models that combines gemcitabine + FOLFOX (fluoropyrimidine backbone coupled to oxaliplatin) poly-chemotherapy with low-dose s. c. recombinant interleukin-2 (rIL-2) and granulocyte-macrophage colony stimulating factor (GM-CSF). Promising antitumor effects in metastatic colorectal cancer (mCRC) patients were obtained in previous phase II and III trials. Here we report the results of 15 years of follow-up. Methods: This is a multi-institutional retrospective analysis including 179 mCRC patients receiving GOLFIG regimen between June 2002 and June 2018. Sixty-two of them received the treatment as frontline (enrolled in the GOLFIG-2 phase III trial) and 117 as second/third line (49 enrolled in the GOLFIG-1 phase II trial and 68 as compassionate use). One hundred twelve patients showed a primary left side and 67 a primary right side; K/N-ras mutational status was available in 74 cases, and an activating mutation was detected in 33. Kaplan–Meier and Cox regression analyses were carried out to relate PFS and OS with different parameters. Results: Overall, we recorded a mean PFS and OS of 15.28 (95% CI: 10.36–20.20) and 24.6 (95% CI: 19.07–30.14) months, respectively, with 14 patients surviving free of progression for 10 years. This regimen, in our updated survey of the GOLFIG-2 trial, confirmed superiority over FOLFOX in terms of PFS (hazard ratio (HR) = 0.58, p = 0.006) with a trend to a longer OS (HR = 0.69, P = 0.06) in the first line. Our analysis also confirmed significant antitumor activity in pre-treated patients, reporting a mean PFS and OS of 12.55 (95% CI: 7.19–17.9) and 20.28 (95% CI: 14.4–26.13) months, respectively. Immune-related adverse events (irAEs) were recorded in 24% of the cases and were related to a longer survival (HR = 0.36; P = 0.0001). Finally, patients' outcome was not correlated to sex, sidedness, and MT-K/N-ras. Conclusions: The GOLFIG regimen is a reliable underestimated therapeutic option in pre-treated mCRC patients and offers a strong rationale to design further trials

The CHOLEGAS study: multicentric randomized, blinded, controlled trial of gastrectomy plus prophylactic cholecystectomy versus gastrectomy only, in adults submitted to Gastric cancer surgery with curative intent

<p>Abstract</p> <p>Background</p> <p>The incidence of gallstones and gallbladder sludge is known to be higher in patients after gastrectomy than in general population. This higher incidence is probably related to surgical dissection of the vagus nerve branches and the anatomical gastrointestinal reconstruction. Therefore, some surgeons perform routine concomitant cholecystectomy during standard surgery for gastric malignancies. However, not all the patients who are diagnosed to have cholelithiasis after gastric cancer surgery will develop symptoms or require additional surgical treatments and a standard laparoscopic cholecystectomy is feasible even in those patients who underwent previous gastric surgery. At the present, no randomized study has been published and the decision of gallbladder management is left to each surgeon preference.</p> <p>Design</p> <p>The study is a randomized controlled investigation. The study will be performed in the General and Oncologic Surgery, Department of Oncology – Azienda Ospedaliero-Universitaria Careggi – Florence – Italy, a large teaching institution, with the participation of all surgeons who accept to be involved in, together with other Italian Surgical Centers, on behalf of the GIRCG (Italian Research Group for Gastric Cancer).</p> <p>The patients will be randomized into two groups: in the first group the patient will be submitted to prophylactic cholecystectomy during standard surgery for curable gastric cancer (subtotal or total gastrectomy), while in the second group he/she will be submitted to standard gastric surgery only.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov ID. NCT00757640</p

Renal Cell Carcinoma with Unusual Metastasis to the Small Intestine Manifesting as Extensive Polyposis: Successful Management with Intraoperative Therapeutic Endoscopy

We present here a rare clinical case of a 53-year-old gentleman with metastasis from renal cell carcinoma (RCC) to the small intestine presenting with extensive polyposis and massive gastrointestinal bleeding which was successfully managed with intraoperative endoscopic polypectomy and segmental small bowel resection. The patient presented with melena 2 weeks after right nephrectomy for RCC. Capsule endoscopy found extensive polyposis throughout the small bowel, and the histological features confirmed the diagnosis of metastatic RCC. The patient eventually underwent laparotomy with intraoperative endoscopy of the entire small bowel. Most of the polyps were removed by snare polypectomy. Three segments of the small bowel with extensive transmural involvement had to be resected with primary anastomosis. In the 2 months following his surgery, the patient had no further evidence of gastrointestinal bleeding. The decision of meticulously removing close to 100 polyps by intraoperative endoscopy prevented the patient from requiring total small bowel resection and lifelong dependence on parenteral nutrition. In conclusion, gastrointestinal bleeding in a patient with known RCC should always trigger full gastrointestinal work-up including capsule endoscopy and, if necessary, double balloon enteroscopy

Synthesis of novel MMT/acyl-protected nucleo alanine monomers for the preparation of DNA/alanyl-PNA chimeras

Alanyl-peptide nucleic acid (alanyl-PNA)/DNA chimeras are oligomers envisaged to be beneficial in efficient DNA diagnostics based on an improved molecular beacon concept. A synthesis of alanyl-PNA/DNA chimera can be based on the solid phase assembly of the oligomer with mixed oligonucleotide/peptide backbone under DNA synthesis conditions, in which the nucleotides are introduced as phosphoramidites, whereas the nucleo amino acids make use of the acid labile monomethoxytrityl (MMT) group for temporary protection of the α-amino groups and acyl protecting groups for the exocyclic amino functions of the nucleobases. In this work, we realized for the first time the synthesis of all four MMT/acyl-protected nucleo alanines, achieved by deprotection/reprotection of the newly synthesized Boc/acyl intermediates, useful monomers for the obtainment of (alanyl-PNA)/DNA chimeras by conditions fully compatible with the standard phosphoramidite DNA synthesis strategy

Past, present and future of adjuvant HIPEC in patients at high risk for colorectal peritoneal metastases

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