Evaluation of the cytotoxic potential of Securidaca longepedunculata on human breast adenocarcinoma (MCF-7) cells

The prevalence of cancer has increased interest in the role of complementary and alternative medicine, employing the use of plant products. Securidaca longepedunculata (SL) is an example of plant product which serves as a major component of anticancer decoctions in Nigeria. In other to scientifically ascertain this claim, this study was carried out to evaluates the cytotoxic potential of the crude extract and fractions of SL root bark against human breast adenocarcinoma (MCF-7) cell line. The root back of SL was pulverized and extracted with 80% methanol to yield a crude extract which was then submitted to liquid–liquid fractionation with dichloromethane (DCM) and butanol (BUT). The extract and fractions were subjected to Gas Chromatography-Mass Spectrometry (GC-MS). MCF-7 cell line was treated with graded concentrations (9.77 – 5000 μg ml-1) of the aqueous methanol crude extract as well as the DCM and BUT fractions for 24 or 48 hours. Cell viability was thereafter measured by XTT proliferation assay. The inhibitory activities of the aqueous methanolic crude extract was found to be both dose-dependent and time independent with IC50 values of 2241 μg ml-1 and 1808 μg ml-1 after 24 and 48 hours respectively. The DCM and BUT fractions were significantly (p < 0.05) cytotoxic with IC50 values of 86.27 μg ml-1 and 12.08 μg ml-1 respectively after 48 hours of treatment. The study provide evidence that BUT fractions of SL has the highest potential to significantly show anticancer properties

Modulating Tumor Microenvironment: A Review on STK11 Immune Properties and Predictive vs Prognostic Role for Non-small-cell Lung Cancer Immunotherapy

The quest for immunotherapy (IT) biomarkers is an element of highest clinical interest in both solid and hematologic tumors. In non-small-cell lung cancer (NSCLC) patients, besides PD-L1 expression evaluation with its intrinsic limitations, tissue and circulating parameters, likely portraying the tumor and its stromal/immune counterparts, have been proposed as potential predictors of IT responsiveness. STK11 mutations have been globally labeled as markers of IT resistance. After a thorough literature review, STK11 mutations condition the prognosis of NSCLC patients receiving ICI-containing regimens, implying a relevant biological and clinical significance. On the other hand, waiting for prospective and solid data, the putative negative predictive value of STK11 inactivation towards IT is sustained by less evidence. The physiologic regulation of multiple cellular pathways performed by STK11 likely explains the multifaceted modifications in tumor cells, stroma, and tumor immune microenvironment (TIME) observed in STK11 mutant lung cancer, particularly explored in the molecular subgroup of KRAS co-mutation. IT approaches available thus far in NSCLC, mainly represented by anti-PD-1/PD-L1 inhibitors, are not promising in the case of STK11 inactivation. Perceptive strategies aimed at modulating the TIME, regardless of STK11 status or specifically addressed to STK11-mutated cases, will hopefully provide valid therapeutic options to be adopted in the clinical practice

A new variant in signal peptide of the human luteinizing hormone receptor (LHCGR) affects receptor biogenesis causing leydig cell hypoplasia

The human luteinizing hormone/chorionic gonadotropin receptor (LHCGR) plays a fundamental role in male and female reproduction. In males, loss-of-function mutations in LHCGR have been associated with distinct degrees of impairment in pre- and postnatal testosterone secretion resulting in a variable phenotypic spectrum, classified as Leydig cell hypoplasia (LCH) type 1 (complete LH resistance and disorder of sex differentiation) and type 2 (partial LH resistance with impaired masculinization and fertility).Here, we report the case of an adolescent who came to the pediatric endocrinologist at the age of 12 years old for micropenis and cryptorchidism. Testis biopsy showed profound Leydig cell hypoplasia and absent germinal line elements (Sertoli-only syndrome). The sequence analysis of the LHCGR gene showed the presence of a compound heterozygosity, being one variation, c.1847C>A p.S616Y, already described in association to Hypergonadotropic Hypogonadism (HH), and the other, c.29 C>T p.L10P, a new identified variant in the putative signal peptide of LHCGR. Functional and structural studies provide first evidence that LHCGR have a functional and cleavable signal peptide required for receptor biogenesis. Moreover, we demonstrate the pathogenic role of the novel p.L10P allelic variant, which has to be considered a loss-of-function mutation significantly contributing, in compound heterozygosity with p.S616Y, to the Leydig cell hypoplasia type 2 observed in our patient

Phase II, Open-label, Single-arm, Multicenter Study to Assess the Activity and Safety of Alectinib as Neoadjuvant Treatment in Surgically Resectable Stage III ALK-positive NSCLC: ALNEO Trial

Background: Alectinib is a potent anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitor (TKI) which is currently used in the first-line setting of advanced ALK+ non-small cell lung cancer (NSCLC). Despite favorable results in the metastatic setting, the activity of alectinib in locally-advanced ALK+ NSCLC as a neoadjuvant treatment remains to be assessed. We report the case of a patient with stage IIIA ALK+ NSCLC (cT2aN2) who received alectinib as neoadjuvant treatment, achieving major pathological response (MPR) at pathologic examination. Hence we present the treatment rationale and study design of a phase II, open-label, single-arm, multicenter clinical trial (ALNEO study, EUDRACT number 2020-003432-25). Materials and Methods: Patients with potentially resectable stage III ALK+ NSCLC (any T with N2, T4N0-1) will be registered to receive oral alectinib 600 mg twice daily for 2 cycles of 4 weeks each (8 weeks totally) during the neoadjuvant phase. After definitive surgery, patients will enter in the adjuvant setting, during which they will receive alectinib 600 mg twice daily for 24 cycles (96 weeks). The primary endpoint is MPR, defined as ≤10% residual viable tumor cells histologically detected in the resected primary tumor and all resected lymph nodes after surgery. Secondary endpoints include pathological complete response, objective response, event-free survival, disease-free survival, overall survival, adverse events. Conclusions: Our case report supports the feasibility of alectinib as neoadjuvant treatment. ALNEO study will further explore the activity and safety of this novel treatment strategy

Small Cell Lung Cancer Transformation as a Resistance Mechanism to Osimertinib in Epidermal Growth Factor Receptor-Mutated Lung Adenocarcinoma: Case Report and Literature Review

Introduction: Small cell lung cancer (SCLC) transformation represents a mechanism of resistance to osimertinib in EGFR-mutated lung adenocarcinoma, which dramatically impacts patients' prognosis due to high refractoriness to conventional treatments. Case Description: We present the case of a patient who developed a SCLC phenotypic transformation as resistance mechanism to second-line osimertinib for T790M-positive EGFR-mutated NSCLC. Our patient received platinum–etoposide doublet following SCLC switch and achieved a modest clinical benefit which lasted 4 months. NGS and IHC analyses for p53 and Rb were performed on subsequent liver biopsies, revealing baseline TP53 mutation and complete absence of p53 and Rb expression. Primary cell cultures were established following a liver biopsy at the time of SCLC transformation, and drug sensitivity assays showed meaningful cell growth inhibition when osimertinib was added to platinum–etoposide compared with control (p < 0.05). A review of the current literature regarding SCLC transformation after failure of osimertinib was performed. Conclusions: Based on retrospective data available to date, platinum–etoposide chemotherapy is the preferred treatment choice in the occurrence of SCLC transformation after osimertinib failure. The extension of osimertinib in combination with chemotherapy in the occurrence of SCLC transformation as resistance mechanism to osimertinib is a matter of debate. The combination of osimertinib and platinum–etoposide was effective in inhibiting cell growth in our primary cell cultures. Clinical studies are needed to further explore this combination in the occurrence of SCLC transformation as a resistance mechanism to osimertinib

Afatinib therapy in case of EGFR G724S emergence as resistance mechanism to osimertinib

Osimertinib is a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) used both as the first-line treatment of EGFR-mutated non-small cell lung cancer patients and in second-line after T790M-positive disease progression to first- or second-generation TKIs. Unfortunately, patients unavoidably experience disease progression to osimertinib and the current research is focused on resistance mechanisms and the relative therapeutic strategy. We report the case of a patient with advanced EGFR-mutated (exon 19 deletion and T790M-positive) non-small cell lung cancer who developed disease progression to osimertinib characterized by the loss of T790M concurrently with the emergence of G724S EGFR mutation, which was tackled by subsequent afatinib treatment. Next-generation sequencing molecular study of rebiopsy at time of progression to osimertinib revealed the persistence of EGFR exon 19 deletion, loss of T790M with a new G724S EGFR mutation; other concomitant mechanisms were excluded. Retrospective analysis of cell-free DNA revealed the emergence of G724S EGFR mutation four months before the radiologically-proven disease progression. The patient, after chemotherapy, was treated with afatinib with clinical and radiological benefit. Our case report contributes to increase the knowledge on acquired resistance mechanisms to osimertinib treatment, and it shows, for the first time, the efficacy of afatinib in the case of T790M loss and emergence of G724S EGFR mutation. Anti-Cancer Drugs 32: 758-762 Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved

Efficacy of the cdk4/6 dual inhibitor abemaciclib in egfr-mutated nsclc cell lines with different resistance mechanisms to osimertinib

Abemaciclib is an inhibitor of cyclin-dependent kinases (CDK) 4 and 6 that inhibits the transition from the G1 to the S phase of the cell cycle by blocking downstream CDK4/6-mediated phosphorylation of Rb. The effects of abemaciclib alone or combined with the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) osimertinib were examined in a panel of PC9 and HCC827 osimertinib-resistant non-small cell lung cancer (NSCLC) cell lines carrying EGFR-dependent or-independent mechanisms of intrinsic or acquired resistance. Differently from sensitive cells, all the resistant cell lines analyzed maintained p-Rb, which may be considered as a biomarker of osimertinib resistance and a potential target for therapeutic intervention. In these models, abemaciclib inhibited cell growth, spheroid formation, colony formation, and induced senes-cence, and its efficacy was not enhanced in the presence of osimertinib. Interestingly, in osimertinib sensitive PC9, PC9T790M, and H1975 cells the combination of abemaciclib with osimertinib significantly inhibited the onset of resistance in long-term experiments. Our findings provide a preclinical support for using abemaciclib to treat resistance in EGFR mutated NSCLC patients progressed to osimertinib either as single treatment or combined with osimertinib, and suggest the combination of osimertinib with abemaciclib as a potential approach to prevent or delay osimertinib resistance in first-line treatment

Singly generated quasivarieties and residuated structures

A quasivariety K of algebras has the joint embedding property (JEP) iff it is generated by a single algebra A. It is structurally complete iff the free countably generated algebra in K can serve as A. A consequence of this demand, called "passive structural completeness" (PSC), is that the nontrivial members of K all satisfy the same existential positive sentences. We prove that if K is PSC then it still has the JEP, and if it has the JEP and its nontrivial members lack trivial subalgebras, then its relatively simple members all belong to the universal class generated by one of them. Under these conditions, if K is relatively semisimple then it is generated by one K-simple algebra. It is a minimal quasivariety if, moreover, it is PSC but fails to unify some finite set of equations. We also prove that a quasivariety of finite type, with a finite nontrivial member, is PSC iff its nontrivial members have a common retract. The theory is then applied to the variety of De Morgan monoids, where we isolate the sub(quasi)varieties that are PSC and those that have the JEP, while throwing fresh light on those that are structurally complete. The results illuminate the extension lattices of intuitionistic and relevance logics

Dynamic evaluation of circulating mirna profile in egfr‐ mutated nsclc patients treated with egfr‐tkis

Background: Resistance to EGFR‐TKIs constitutes a major challenge for the management of EGFR‐mutated NSCLC, and recent evidence suggests that deregulation of specific microRNAs (miRNAs) may influence resistance to targeted agents. In this retrospective study, we explored the role of specific plasmatic miRNAs (miR‐21, miR‐27a and miR‐181a) as a surrogate for predicting EGFR‐TKI performance in EGFR‐mutated NSCLC patients. Methods: Plasma samples of 39 advanced EGFR‐mutated NSCLC patients treated with EGFR‐TKIs were collected at different points in time and miRNA levels were assessed by RT‐PCR. Results: Higher basal values of miR‐21 were reported in patients who achieved a partial/complete response (PR/CR) compared to those with stability/progression of disease (SD/PD) (p = 0.011). Along the same line, patients who experienced a clinical benefit lasting at least six months displayed higher basal levels of circulating miR‐21 (p = 0.039). However, dynamic evaluation of miRNA values after two months from the start of EGFR‐TKI treatment showed that patients who experienced SD had an increase in miR‐21 levels (Fold Change [FC] = 2.6) compared to patients achieving PR/CR (p = 0.029). The same tendency was observed for miR‐27a (FC = 3.1) and miR‐181a (FC = 2.0), although without reaching statistical significance. Remarkably, preclinical studies showed an increase in miR‐21 levels in NSCLC cells that became resistant after exposure to EGFR‐TKIs. Conclusions: Our study provides interesting insights on the role of circulating miRNAs, in particular miR‐21, and their dynamic change over time in predicting EGFR‐TKI response in EGFR‐mutated NSCLC