A Novel Combination of Sotorasib and Metformin Enhances Cytotoxicity and Apoptosis in KRAS-Mutated Non-Small Cell Lung Cancer Cell Lines through MAPK and P70S6K Inhibition.

Novel inhibitors of KRAS with G12C mutation (sotorasib) have demonstrated short-lasting responses due to resistance mediated by the AKT-mTOR-P70S6K pathway. In this context, metformin is a promising candidate to break this resistance by inhibiting mTOR and P70S6K. Therefore, this project aimed to explore the effects of the combination of sotorasib and metformin on cytotoxicity, apoptosis, and the activity of the MAPK and mTOR pathways. We created dose-effect curves to determine the IC50 concentration of sotorasib, and IC10 of metformin in three lung cancer cell lines; A549 (KRAS G12S), H522 (wild-type KRAS), and H23 (KRAS G12C). Cellular cytotoxicity was evaluated by an MTT assay, apoptosis induction through flow cytometry, and MAPK and mTOR pathways were assessed by Western blot. Our results showed a sensitizing effect of metformin on sotorasib effect in cells with KRAS mutations and a slight sensitizing effect in cells without K-RAS mutations. Furthermore, we observed a synergic effect on cytotoxicity and apoptosis induction, as well as a notable inhibition of the MAPK and AKT-mTOR pathways after treatment with the combination, predominantly in KRAS-mutated cells (H23 and A549). The combination of metformin with sotorasib synergistically enhanced cytotoxicity and apoptosis induction in lung cancer cells, regardless of KRAS mutational status.

S-allylcysteine induces cytotoxic effects in two human lung cancer cell lines via induction of oxidative damage, downregulation of Nrf2 and NF-κB, and apoptosis.

In this study, we investigated the putative cytotoxic effect elicited by the garlic-derived compound S-allylcysteine (SAC) in two human cancer cell lines (HCC827 and NCI-H1975) in order to develop an experimental approach to the therapeutic potential of this molecule for lung cancer. Cells were incubated for 24, 48 and 72 h in the presence of SAC (10 or 20 mM), which resulted in a concentration- and time-dependent decrease in cell viability and culture confluence in both cell lines. These effects were contrasted with - and validated through - those observed in an immortalized but nontumorigenic epithelial cell line from human bronchial epithelium (BEAS-2B, negative control) and an adenocarcinoma human alveolar basal epithelial cell line (A549, positive control). SAC (20 mM at 72 h) also increased the oxidative damage to lipids, augmented apoptosis, and decreased the expression of the nuclear factor erythroid 2-related factor 2 (Nrf2) and the nuclear factor kappa B (NF-κB) proteins in HCC827 and NCI-H1975 cells. Our results establish the efficacy of SAC in reducing malignant growth and proliferation of lung tumor cells. This effect is mediated by the induction of oxidative damage associated with the downregulation of Nrf2 and NF-κB and their corresponding signaling pathways.

Malignant Glioma Therapy by Vaccination with Irradiated C6 Cell-Derived Microvesicles Promotes an Antitumoral Immune Response.

Glioblastoma is the most common and malignant tumor of the CNS, with a mean survival of 14 months after diagnosis. Its unfavorable prognosis reveals the need for novel therapies. It is known that radiation can induce a systemic antitumor effect. Tumor cells produce and release microvesicles in response to cell damage such as radiation. Microvesicles contain a plethora of bioactive molecules, including antigens involved in modulation of the immune response. In this study, we characterized and evaluated irradiated C6 cell-derived microvesicles as a therapeutic vaccination in C6 malignant glioma. Cultured C6 glioma cells were irradiated with a single dose of 50 Gy to obtain the microvesicles. Subcutaneous implantation of C6 cells was performed when the tumor reached 2 cm in diameter, and non-irradiated and irradiated C6 cell-derived microvesicles were administered subcutaneously. Tumor growth, apoptosis, and immunophenotypes were determined. Reduction of tumor volume (more than 50%) was observed in the group treated with irradiated C6 cell-derived microvesicles compared with the control (p = 0.03). The percentages of infiltrative helper, cytotoxic, and regulatory T lymphocytes as well as apoptotic cells were increased in tumors from immunized rats compared with controls. These findings make microvesicle-based vaccination a promising immunotherapeutic approach against glioblastoma.

Mutational profile by targeted next generation sequencing of non-small cell lung cancer in the Mexican population.

OBJECTIVE: Targeted next-generation sequencing (t-NGS) has revolutionized clinical diagnosis allowing multiplexed detection of genomic alterations. This study evaluated the profile of somatic mutations by t-NGS in Mexican patients with nonsmall cell lung cancer (NSCLC). MATERIALS AND METHODS: Genomic DNA was extracted from 90 lung adenocarcinomas and sequences were generated for a panel of 48 cancer genes. Epidermal Growth Factor Receptor (EGFR) mutations were detected in parallel by quantitative PCR. RESULTS: The mutational profile of NSCLC revealed alterations in 27 genes, where TP53 (47.8%) and EGFR (36.7%) exhibited the highest mutation rates. EGFR Q787 mutations were present in 14 cases (15.6%), 10 cases had exon 19 deletions (11.1%), seven cases had L858R (7.8%). The mutational frequency for genes like EGFR, MET, HNF1A, HER2 and GUSB was different compared to caucasian population. CONCLUSIONS: t-NGS improved NSCLC treatments efficacy due to its sensitivity and specificity. A distinct pattern of somatic mutations was found in Mexican population.

OBJETIVO: La secuenciación dirigida de nueva generación (SNG) permite la detección múltiple de mutaciones. Este estudio evalúa el perfil de mutaciones somáticas por SNG en pacientes mexicanos con cáncer de pulmón de células no pequeñas(CPCNP). MATERIAL Y MÉTODOS: Se aisló ADN de 90 muestras de pacientes con CPCNP y se analizarón 48 genes relacionados con cáncer. Las mutaciones del receptor del factor de crecimiento epidérmico (EGFR) se detectaron por PCR cuantitativa. RESULTADOS: Se detectaron alteraciones en 27 genes. Las mutaciones más frecuentes fueron TP53 (47.8%) y EGFR (36.7%). En el gen EGFR, 14 casos fueron mutaciones Q787 (15.6%), 10 presentaron microdeleciones en el exón 19 (11.1%), y siete en L858R (7.8%). La frecuencia de mutación en EGFR, MET, HNF1A, HER2 y GUSB fue diferente en comparación con población caucásica. CONCLUSIONES: NGS modifica el tratamiento del paciente con CPCNP por su sensibilidad y especificidad para detectar mutaciones. La población mexicana presenta un perfil mutacional particula.

Association between nuclear expression of retinoic acid receptor alpha and beta and clinicopathological features and prognosis of advanced non-small cell lung cancer.

BACKGROUND: Transcription factors such as retinoic acid receptor alpha (RARα) and beta (RARß) and Yin Yang 1 (YY1) are associated with the progression of non-small cell lung cancer (NSCLC). In particular, a lack of RARß expression is associated with NSCLC development. The aim of this study was to analyze the expression of RARα, RARß and YY1 and their relationship with prognosis in patients with advanced NSCLC. METHODS: The expression of RARα, RARß and YY1 was assessed by immunohistochemistry and quantitative computerized image software. RESULTS: Eighty-five patients treated with platinum-based chemotherapy were included in the analysis. The mean and standard deviation of the nuclear expression of RARα, RARß and YY1 were 184.5 ± 124.4, 18 ± 27 and 16.6 ± 20.5, respectively. The nuclear expression of RARß was associated with the nuclear expression of YY1 (R 2 = 0.28; p value < 0.0001). Patients with high nuclear expression of YY1 were likely to be non-smokers (61.9 vs 40.5 %). Median progression-free survival (PFS) was 5.9 months (3.48-8.28). Low expression of RARα was independently associated with worse PFS following chemotherapy (10.3 vs 5.46 months p = 0.040). Median overall survival (OS) was 15.6 months (4.5-26.7), and lower nuclear expression of RARß was independently associated with shorter OS (27.5 vs 8.7 months; p = 0.037). CONCLUSION: Our study suggests that the loss of RARs is associated with a worse prognosis and these receptors could be a potential molecular target for NSCLC.

Interplay between Cellular and Molecular Inflammatory Mediators in Lung Cancer.

Inflammation is a component of the tumor microenvironment and represents the 7th hallmark of cancer. Chronic inflammation plays a critical role in tumorigenesis. Tumor infiltrating inflammatory cells mediate processes associated with progression, immune suppression, promotion of neoangiogenesis and lymphangiogenesis, remodeling of extracellular matrix, invasion and metastasis, and, lastly, the inhibition of vaccine-induced antitumor T cell response. Accumulating evidence indicates a critical role of myeloid cells in the pathophysiology of human cancers. In contrast to the well-characterized tumor-associated macrophages (TAMs), the significance of granulocytes in cancer has only recently begun to emerge with the characterization of tumor-associated neutrophils (TANs). Recent studies show the importance of CD47 in the interaction with macrophages inhibiting phagocytosis and promoting the migration of neutrophils, increasing inflammation which can lead to recurrence and progression in lung cancer. Currently, therapies are targeted towards blocking CD47 and enhancing macrophage-mediated phagocytosis. However, antibody-based therapies may have adverse effects that limit its use.

Association between AT1 and AT2 angiotensin II receptor expression with cell proliferation and angiogenesis in operable breast cancer.

Angiotensin II (ANGII) has been associated with vascular proliferation in tumor and non-tumor models through its receptors AT1 and AT2. Our objective was to determine AT1 and AT2 receptor expression in operable breast cancer and its association with tumor grade, vascular density, and cellular proliferation. Seventy-seven surgically malignant breast tumors with no distant metastasis were included, and 7 benign lesions were used as controls. AT1 and AT2 receptor expression was determined by RT-PCR and immunohistochemistry (IHC) in 68 out of the 77 malignant lesions and in the 7 benign lesions. AT1 and AT2 receptor expression was detected in 35.3 and 25 % of cases, in both RT-PCR and IHC. Tumors that express AT1 showed an increase in T3 stage (92.3 vs. 7.7 % p < 0.001), mitotic index (4 ± 1 vs 2 ± 1, p = 0.05), vascular density (15 ± 3 vs 8 ± 5, p = 0.05), and cellular proliferation (85 ± 18 vs 55 ± 10, p = 0.01) versus AT1-negative lesions. Non-differences between clinical-pathologic variables and AT2 expression were found. AT1 receptor expression was associated to enhance angiogenesis and cellular proliferation rate, but no relationship with AT2 was found. ANGII and its peptides might play a role in the development and pathophysiology of breast cancer, and this could be valuable in the in the development of targeted therapies.

RB mutation and RAS overexpression induce resistance to NK cell-mediated cytotoxicity in glioma cells.

Several theories aim to explain the malignant transformation of cells, including the mutation of tumor suppressors and proto-oncogenes. Deletion of Rb (a tumor suppressor), overexpression of mutated Ras (a proto-oncogene), or both, are sufficient for in vitro gliomagenesis, and these genetic traits are associated with their proliferative capacity. An emerging hallmark of cancer is the ability of tumor cells to evade the immune system. Whether specific mutations are related with this, remains to be analyzed. To address this issue, three transformed glioma cell lines were obtained (Rb(-/-), Ras(V12), and Rb(-/-)/Ras(V12)) by in vitro retroviral transformation of astrocytes, as previously reported. In addition, Ras(V12) and Rb(-/-)/Ras(V12) transformed cells were injected into SCID mice and after tumor growth two stable glioma cell lines were derived. All these cells were characterized in terms of Rb and Ras gene expression, morphology, proliferative capacity, expression of MHC I, Rae1δ, and Rae1αßγδε, mult1, H60a, H60b, H60c, as ligands for NK cell receptors, and their susceptibility to NK cell-mediated cytotoxicity. Our results show that transformation of astrocytes (Rb loss, Ras overexpression, or both) induced phenotypical and functional changes associated with resistance to NK cell-mediated cytotoxicity. Moreover, the transfer of cell lines of transformed astrocytes into SCID mice increased resistance to NK cell-mediated cytotoxicity, thus suggesting that specific changes in a tumor suppressor (Rb) and a proto-oncogene (Ras) are enough to confer resistance to NK cell-mediated cytotoxicity in glioma cells and therefore provide some insight into the ability of tumor cells to evade immune responses.

Varias teorías pretenden explicar la transformación maligna de las células, como es la mutación de genes supresores de tumor y proto-oncogenes. La deleción de Rb (un supresor de tumor), la sobreexpresión de Ras mutado (un proto-oncogén), o ambos, son suficientes para desarrollar gliomagénesis in vitro, y estas características genéticas se asocian con su alta tasa de proliferación. Un rasgo distintivo del cáncer es la capacidad de las células tumorales para evadir el sistema inmune. Por lo que en este estudio analizamos si las mutaciones específicas están relacionadas con la evasión de la respuesta inmune. Para abordar esta cuestión, tres líneas celulares de glioma transformadas se obtuvieron (Rb−/−, RasV12, y Rb−/−/RasV12) mediante transformación retroviral de astrocitos in vitro, reportado anteriormente. Además, las células transformadas RasV12 y Rb−/−/RasV12 fueron inyectadas en ratones SCID y después del crecimiento del tumor se obtuvieron dos líneas celulares de glioma estables. En todas las células se determinaron la expresión génica Rb y Ras, morfología, capacidad de proliferación, expresión de MHC I, Rae1δ, and Rae1αßγδε, mult1, H60a, H60b, H60c, como ligandos para receptores de células NK, y su susceptibilidad a la citotoxicidad mediada por células NK. Nuestros resultados muestran que la transformación de los astrocitos (pérdida de Rb, la sobreexpresión de Ras, o ambos) indujo cambios fenotípicos y funcionales asociados con la resistencia a la citotoxicidad mediada por células NK. Además, la transferencia de astrocitos transformados dentro de ratones SCID aumento la resistencia a la citotoxicidad mediada por células NK, lo que se sugiere que los cambios específicos en un supresor de tumores (Rb) y un proto-oncogén (Ras) son suficientes para conferir resistencia a la citotoxicidad mediada por células NK en células de glioma y, por tanto, proporcionar una idea de la capacidad de las células tumorales para evadir la respuesta inmune.

Retinoic acid reduces solvent-induced neuropathy and promotes neural regeneration in mice.

In humans, exposure to organic solvents (OS) is frequent in work activities or as a recreational inhalant, inducing severe neuropathy (secondary to demyelization of peripheral nerves). We have previously shown that all-trans retinoic acid (ATRA) increases local content of neural growth factor (NGF), improving peripheral neuropathy of diverse origins. In this study, we evaluated the effect of ATRA on OS-induced peripheral neuropathy in experimental mice. Two simultaneous experiments were performed. The first one aimed to evaluate ATRA for the prevention of damage induced by OS, the second to test ATRA as an OS-induced neuropathy treatment. Nociceptive threshold latency and NGF concentration in serum and in peripheral nerves were determined. Morphological changes and evidence of sciatic nerve regeneration were evaluated. Mice exposed to OS developed neuropathy and axonal degeneration. ATRA diminished the effects of OS inhalation on sensorial changes and nerve morphology. Treatment with ATRA reversed sensorial and nerve morphological changes of OS-induced neuropathy, and this was associated with increased contents of NGF. Similar to previous experiences on diabetic and toxic neuropathy, ATRA reduced and partially reversed the peripheral neuropathy caused by OS exposure. These favorable effects apparently are due to local production of NGF induced by neural regeneration in response to the administration of retinoic acid.

Impact of KRASG12D subtype and concurrent pathogenic mutations on advanced non-small cell lung cancer outcomes.

PURPOSE: Mutations in the Kirsten rat sarcoma viral (KRAS) oncogene constitute a significant driver of lung adenocarcinoma, present in 10-40% of patients, which exhibit heterogeneous clinical outcomes, mainly driven by concurrent genetic alterations. However, characterization of KRAS mutational subtypes and their impact on clinical outcomes in Latin America is limited. METHODS: A cohort study was conducted at the National Cancer Institute (INCan) of Mexico. Individuals with advance-staged of adenocarcinoma and KRAS mutations, detected by next-generation sequencing, having undergone at least one line of therapy were included for analysis. Clinical and pathological characteristics were retrieved from institutional database from June 2014 to March 2023. RESULTS: KRAS was identified in fifty-four (15.6%) of 346 patients, among which 50 cases were included for analysis. KRASG12D (n = 16, 32%) and KRASG12C (n = 16, 32%) represented the most prevalent subtypes. KRASG12D mutations were associated with female (p = 0.018), never smokers (p = 0.108), and concurrences with EGFR (25.0% vs. 17.6%, p = 0.124) and CDKN2A (18.8% vs. 14.7%, p = 0.157). KRASG12D patients showed a better ORR (66.6% vs. 30.0%; OR 4.66, 95% CI 1.23-17.60, p = 0.023) and on multivariate analysis was significantly associated with better PFS (HR 0.36, 95% CI 0.16-0.80; p = 0.012) and OS (HR 0.24, 95% CI 0.08-0.70; p = 0.009). CONCLUSIONS: To our knowledge, this study represents the first effort to comprehensively characterize the molecular heterogeneity of KRAS-mutant NSCLC in Latin American patients. Our data reinforce the current view that KRAS-mutated NSCLC is not a single oncogene-driven disease and emphasizes the prognostic impact of diverse molecular profiles in this genomically defined subset of NSCLC. Further validation is warranted in larger multicenter Latin American cohorts to confirm our findings.

Prevalence of pathogenic or likely pathogenic germline variants in cancer predisposition genes among selected patients with lung adenocarcinoma: The GERMLUNG study.

INTRODUCTION: Pathogenic or likely pathogenic germline variants (PGVs) in cancer predisposition genes may play a role in lung cancer (LC) susceptibility. However, determining an eligible population for genetic testing remains uncertain. This study aimed to assess the prevalence of PGVs in a selected cohort of individuals with lung adenocarcinoma. METHODS: A cross-sectional cohort study was conducted to assess the PGVs rate in lung adenocarcinoma patients with a family history of LC, young-onset presentation, history of never/light smoking, or actionable genomic alterations (AGAs). Sequencing was performed using Sophia Hereditary Cancer Solution panel F, including 144 cancer predisposition genes. Variants classified as pathogenic or likely pathogenic were included for further analysis. RESULTS: Of 201 patients, 43 (21.4 %) exhibited PGVs, among which 64.5 % were DNA damage repair genes, and 86.1 % were clinically actionable. The main PGVs were in ATM (9.3 %), TP53 (6.9 %), BRCA2 (6.9 %), and CHEK2 (6.9 %) genes. PGVs were associated with male sex (adjusted odds ratio [aOR] 2.46, 95 % CI 1.15-5.32, p = 0.021), along with a trend toward association with AGAs (aOR 6.04, 95 % CI 0.77-49.74, p = 0.094). CONCLUSIONS: In this study, a high PGVs prevalence was identified based on our selection criteria, which represents an effective strategy to identify candidates for germline genomic testing, potential screening strategies in close relatives, and personalized therapeutic modalities. Our results warrant further exploration in other populations to confirm them.

Initial immunopathogenesis of multiple sclerosis: innate immune response.

Multiple sclerosis (MS) is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. The hallmark to MS is the demyelinated plaque, which consists of a well-demarcated hypocellular area characterized by the loss of myelin, the formation of astrocytic scars, and the mononuclear cell infiltrates concentrated in perivascular spaces composed of T cells, B lymphocytes, plasma cells, and macrophages. Activation of resident cells initiates an inflammatory cascade, leading to tissue destruction, demyelination, and neurological deficit. The immunological phenomena that lead to the activation of autoreactive T cells to myelin sheath components are the result of multiple and complex interactions between environment and genetic background conferring individual susceptibility. Within the CNS, an increase of TLR expression during MS is observed, even in the absence of any apparent microbial involvement. In the present review, we focus on the role of the innate immune system, the first line of defense of the organism, as promoter and mediator of cross reactions that generate molecular mimicry triggering the inflammatory response through an adaptive cytotoxic response in MS.

Impact of Tyrosine Kinase Inhibitors on the Immune Response to SARS-CoV-2 Vaccination in Patients with Non-Small Cell Lung Cancer.

Immune dysregulation and cancer treatment may affect SARS-CoV-2 vaccination protection. Antibody production by B-cells play a vital role in the control and clearance of the SARS-CoV-2 virus. This study prospectively explores B-cell seroconversion following SARS-CoV-2 immunization in healthy individuals and non-small cell lung cancer (NSCLC) patients undergoing oncological treatment. 92 NSCLC patients and 27 healthy individuals' blood samples were collected after receiving any COVID-19 vaccine. Serum and mononuclear cells were isolated, and a serum surrogate virus neutralization test kit evaluated SARS-CoV-2 antibodies. B-cell subpopulations on mononuclear cells were characterized by flow cytometry. Patients were compared based on vaccination specifications and target mutation oncological treatment. A higher percentage of healthy individuals developed more SARS-CoV-2 neutralizing antibodies than NSCLC patients (63% vs. 54.3%; p = 0.03). NSCLC patients receiving chemotherapy (CTX) or tyrosine kinase inhibitors (TKIs) developed antibodies in 45.2% and 53.7%, of cases, respectively, showing an impaired antibody generation. CTX patients exhibited trends towards lower median antibody production than TKIs (1.0, IQR 83 vs. 38.23, IQR 89.22; p = 0.069). Patients receiving immunotherapy did not generate antibodies. A sub-analysis revealed that those with ALK mutations exhibited non-significant trends towards higher antibody titers (63.02, IQR 76.58 vs. 21.78, IQR 93.5; p = 0.1742) and B-cells quantification (10.80, IQR 7.52 vs. 7.22, IQR 3.32; p = 0.1382) against the SARS-CoV-2 spike protein than EGFR patients; nonetheless, these differences were not statistically significant. This study shows that antibodies against SARS-CoV-2 may be impaired in patients with NSCLC secondary to EGFR-targeted TKIs compared to ALK-directed treatment.

PD-L1 expression complements CALGB prognostic scoring system in malignant pleural mesothelioma.

Background: Programmed death ligand-1 (PD-L1) expression is a predictive biomarker in patients with lung cancer, but its role in malignant pleural mesothelioma (MPM) remains unclear. Evidence suggests that higher PD-L1 expression is correlated with worse survival. CALGB is the main scoring system used to predict the benefit of chemotherapy treatment. This study aimed to determine the prognostic value of PD-L1 expression and its addition to CALGB scoring system in patients with MPM. Methods: In this retrospective analysis, we evaluated samples with confirmed locally advanced or metastatic MPM. PD-L1 Tumor Proportional Score (TPS) was determined by immunohistochemistry at diagnosis. Results: 73 patients were included in this study. A cutoff value of 15 was set for a high or low PD-L1 TPS. In total, 71.2% (n=52) and 28.8% (n=21) of individuals harbored low or high PD-L1 expression, respectively. PD-L1High was associated with worse median progression-free Survival (mPFS) [4.9 vs. 10.8 months; HR 2.724, 95% CI (1.44-5.14); p = 0.002] and Overall Survival (OS) [6.0 vs. 20.9 months; HR 6.87, 95% CI (3.4-8.7); p<0.001] compared to patients with PD-L1Low. Multivariate analysis confirmed that PD-L1 expression was an independent factor for PFS and OS in patients with MPM and CALGB score of 5-6. Conclusion: PD-L1 addition to CALGB scale improves its prognostic estimation of MPM survival and should be considered in future research.

Nitroglycerin Plus Whole Intracranial Radiation Therapy for Brain Metastases in Patients With Non-Small Cell Lung Cancer: A Randomized, Open-Label, Phase 2 Clinical Trial.

PURPOSE: Hypoxia has been associated with chemoradioresistance secondary to vascular endothelial growth factor receptor induced by hypoxia-induced factor (HIF). Nitroglycerin (NTG) can reduce HIF-1 in tissues, and this may have antiangiogenic, proapoptotic, and antiefflux effects. Particularly, epidermal growth factor-mutated (EGFRm) tumor cell lines have been shown to overexpress both vascular endothelial growth factor and HIF. In this phase 2 study, we evaluated the effect of transdermal NTG plus whole brain radiation therapy (WBRT) in patients with non-small cell lung cancer (NSCLC) with brain metastases (BM). METHODS: This was an open-label, phase 2 clinical trial with 96 patients with NSCLC and BM. Patients were randomized 1:1 to receive NTG plus WBRT (30 Gy in 10 fractions) or WBRT alone. The primary endpoint was intracranial objective response rate (iORR) evaluated 3 months posttreatment. NTG was administered using a transdermal 36-mg patch from Monday through Friday throughout WBRT administration (10 days). The protocol was retrospectively registered at ClinicalTrials.gov (NCT04338867). RESULTS: Fifty patients were allocated to the control group, and 46 were allocated to the experimental group (NTG); among these, 26 (52%) had EGFRm in the control group and 21 (45.7%) had EGFRm in the NTG arm. In terms of the iORR, patients in the NTG group had a significantly higher response compared with controls (56.5% [n = 26/46 evaluable patients] vs 32.7% [n = 16/49 evaluable patients]; relative risk, 1.73; 95% confidence interval [CI], 1.08-2.78; P = .024). Additionally, patients who received NTG + WBRT had an independently prolonged intracranial progression-free survival (ICPFS) compared with those who received WBRT alone (27.7 vs 9.6; hazard ratio [HR], 0.5; 95% CI, 0.2-0.9; P = .020); this positively affected overall progression-free survival among patients who received systemic therapy (n = 88; HR, 0.5; 95% CI, 0.2-0.9; P = .043). The benefit of ICPFS (HR, 0.4; 95% CI, 0.2-0.9; P = .030) was significant in the EGFRm patient subgroup. No differences were observed in overall survival. A significantly higher rate of vomiting presented in the NTG arm of the study (P = .016). CONCLUSIONS: The concurrent administration of NTG and radiation therapy improves iORR and ICPFS among patients with NSCLC with BM. The benefit in ICPFS is significant in the EGFRm patient subgroup.

Will We Unlock the Benefit of Metformin for Patients with Lung Cancer? Lessons from Current Evidence and New Hypotheses.

Metformin has been under basic and clinical study as an oncological repurposing pharmacological agent for several years, stemming from observational studies which consistently evidenced that subjects who were treated with metformin had a reduced risk for development of cancer throughout their lives, as well as improved survival outcomes when diagnosed with neoplastic diseases. As a result, several basic science studies have attempted to dissect the relationship between metformin's metabolic mechanism of action and antineoplastic cellular signaling pathways. Evidence in this regard was compelling enough that a myriad of randomized clinical trials was planned and conducted in order to establish the effect of metformin treatment for patients with diverse neoplasms, including lung cancer. As with most novel antineoplastic agents, early results from these studies have been mostly discouraging, though a recent analysis that incorporated body mass index may provide significant information regarding which patient subgroups might derive the most benefit from the addition of metformin to their anticancer treatment. Much in line with the current pipeline for anticancer agents, it appears that the benefit of metformin may be circumscribed to a specific patient subgroup. If so, addition of metformin to antineoplastic agents could prove one of the most cost-effective interventions proposed in the context of precision oncology. Currently published reviews mostly rely on a widely questioned mechanism of action by metformin, which fails to consider the differential effects of the drug in lean vs. obese subjects. In this review, we analyze the pre-clinical and clinical information available to date regarding the use of metformin in various subtypes of lung cancer and, further, we present evidence as to the differential metabolic effects of metformin in lean and obese subjects where, paradoxically, the obese subjects have reported more benefit with the addition of metformin treatment. The novel mechanisms of action described for this biguanide may explain the different results observed in clinical trials published in the last decade. Lastly, we present novel hypothesis regarding potential biomarkers to identify who might reap benefit from this intervention, including the role of prolyl hydroxylase domain 3 (PHD3) expression to modify metabolic phenotypes in malignant diseases.

Metformin Enhances TKI-Afatinib Cytotoxic Effect, Causing Downregulation of Glycolysis, Epithelial-Mesenchymal Transition, and EGFR-Signaling Pathway Activation in Lung Cancer Cells.

The combination of metformin and TKIs for non-small cell lung cancer has been proposed as a strategy to overcome resistance of neoplastic cells induced by several molecular mechanisms. This study sought to investigate the effects of a second generation TKI afatinib, metformin, or their combination on three adenocarcinoma lung cancer cell lines with different EGFRmutation status. A549, H1975, and HCC827 cell lines were treated with afatinib, metformin, and their combination for 72 h. Afterwards, several parameters were assessed including cytotoxicity, interactions, apoptosis, and EGFR protein levels at the cell membrane and several glycolytic, oxidative phosphorylation (OXPHOS), and EMT expression markers. All cell lines showed additive to synergic interactions for the induction of cytotoxicity caused by the tested combination, as well as an improved pro-apoptotic effect. This effect was accompanied by downregulation of glycolytic, EMT markers, a significant decrease in glucose uptake, extracellular lactate, and a tendency towards increased OXPHOS subunits expression. Interestingly, we observed a better response to the combined therapy in lung cancer cell lines A549 and H1975, which normally have low affinity for TKI treatment. Findings from this study suggest a sensitization to afatinib therapy by metformin in TKI-resistant lung cancer cells, as well as a reduction in cellular glycolytic phenotype.

LKB1 Loss Assessed by Immunohistochemistry as a Prognostic Marker to First-Line Therapy in Advanced Non-Small-Cell Lung Cancer.

(1) Background: Liver kinase B1 (LKB1) is a tumor suppressor gene involved in cell growth and metabolism. However, its alterations are not routinely assessed for guiding therapy in clinical practice. We assessed LKB1 expression by immunohistochemistry as a potential biomarker. (2) Methods: This bicentric retrospective cohort study analyzed data from patients with advanced NSCLC who initiated platinum-based chemotherapy or epidermal growth factor receptor- tyrosine kinase inhibitor (EGFR-TKI) between January 2016 and December 2020. Kaplan-Meier and Cox regression models were used for survival curves and multivariate analysis. (3) Results: 110 patients were evaluated, and the clinical stage IV predominated the lung adenocarcinoma histology. LKB1 loss was observed in 66.3% of cases. LKB1 loss was associated with non-smokers, the absence of wood smoke exposure and an EGFR wild-type status. The median progression-free survival (PFS) and overall survival (OS) in the population were 11.1 and 26.8 months, respectively, in the loss group, compared with cases exhibiting a positive expression. After an adjustment by age, smoking status, Eastern Cooperative Oncology Group Performance Score (ECOG-PS), EGFR status and type of administered therapy, LKB1 loss was significantly associated with worse PFS and OS. (4) Conclusion: Patients with an LKB1 loss had worse clinical outcomes. This study warrants prospective assessments to confirm the prognostic role of the LKB1 expression in advanced NSCLC.

Clinicopathological and Prognostic Significance of CD47 Expression in Lung Neuroendocrine Tumors.

BACKGROUND: Lung neuroendocrine tumors account for approximately 15% of all lung cancer cases. LNET are subdivided into typical carcinoid (TC), atypical carcinoid (AC), large cell neuroendocrine carcinoma (LCNEC), and small-cell lung cancer (SCLC). The Ki-67 index has been used for decades to evaluate mitotic counts however, the role of Ki-67 as a biomarker for assessing prognosis and guiding therapy in metastatic LNET still lacks feasible clinical validation. Recent clinical trials have indicated that inhibition of CD47 with anti-CD47 antibodies exerts a promising antitumor effect against several human malignancies, including NSCLC, melanoma, and hematologic malignancies. However, the clinical relevance of CD47 expression in LNET has remained unclear. METHODS: We performed a retrospective study in which we analyzed tumor biopsies from 51 patients with a confirmed diagnosis of LNET that received treatment at our hospital. Then, we analyzed if there was any correlation between CD47 expression with any clinical or pathological characteristic. We also analyzed the prognostic significance of CD47, assessed as progression-free survival and overall survival. RESULTS: A total of 51 patients with LNET were enrolled in our study. The mean age at diagnosis was 57.6 (±11.6) years; 30 patients were women (59%). 27.5% of patients were positive for CD47 expression, and 72.5% of patients showed a CD47 expression of less than 1% and were considered as negatives. In patients with high-grade tumors (this time defined as Ki-67 > 40%), the positive expression of CD47 was strongly associated with an increased PFS. Albeit, these differences did not reach statistical significance when analyzing OS. CONCLUSION: Contrary to what happens in a wide range of hematologic and solid tumors, a higher expression of CD47 in patients with LNET is associated with a better progression-free survival, especially in patients with a Ki-67 ≥ 40%. This "paradox" remains to be confirmed and explained by larger studies.

Immune Milieu and Genomic Alterations Set the Triple-Negative Breast Cancer Immunomodulatory Subtype Tumor Behavior.

Triple-negative breast cancer (TNBC) is an aggressive and heterogeneous disease. Seven subtypes have been described based on gene expression patterns. Herein, we characterized the tumor biology and clinical behavior of the immunomodulatory (IM) subtype. METHODS: Formalin-fixed paraffin-embedded tumor samples from 68 high-risk (stage III-IV) TNBC patients were analyzed through microarrays, immunohistochemistry, and DNA sequencing. RESULTS: The IM subtype was identified in 24% of TNBC tumor samples and characterized by a higher intratumoral (intT) and stromal (strml) infiltration of FOXP3+ TILs (Treg) compared with non-IM subtypes. Further, PD-L1+ (>1%) expression was significantly higher, as well as CTLA-4+ intT and strml expression in the IM subtype. Differential expression and gene set enrichment analysis identified biological processes associated with the immune system. Pathway analysis revealed enrichment of the ß-catenin signaling pathway. The non-coding analysis led to seven Long Intergenic Non-Protein Coding RNAs (lincRNAs) (6 up-regulated and 1 down-regulated) that were associated with a favorable prognosis in the TNBC-IM subtype. The DNA sequencing highlighted two genes relevant to immune system responses: CTNNB1 (Catenin ß-1) and IDH1. CONCLUSION: the IM subtype showed a distinct immune microenvironment, as well as subtype-specific genomic alterations. Characterizing TNBC at a molecular and transcriptomic level might guide immune-based therapy in this subgroup of patients.