How Could Antibiotics, Probiotics, and Corticoids Modify Microbiota and Its Influence in Cancer Immune Checkpoint Inhibitors: A Review.

Immunotherapy has become a new paradigm in oncology, improving outcomes for several types of cancer. However, there are some aspects about its management that remain uncertain. One of the key points that needs better understanding is the interaction between immunotherapy and gut microbiome and how modulation of the microbiome might modify the efficacy of immunotherapy. Consequently, the negative impact of systemic antibiotics and corticosteroids on the efficacy of immunotherapy needs to be clarified.

Peripheral Blood TCRß Repertoire, IL15, IL2 and Soluble Ligands for NKG2D Activating Receptor Predict Efficacy of Immune Checkpoint Inhibitors in Lung Cancer.

The development of immune checkpoint inhibitors (ICIs) has changed the therapeutic paradigm of lung cancer (LC), becoming the standard of treatment for previously untreated advanced non-small cell lung cancer (NSCLC) without actionable mutations. It has allowed the achievement of durable responses and resulted in significant survival benefits. However, not all patients respond; hence, molecular biomarkers are needed to help us predict which patients will respond. With this objective, a prospective observational study was designed, including a cohort of 55 patients with NSCLC who received ICIs. We studied whether biomarkers such as TCRß and specific cytokines involved in the regulation of T cell activity were related to the immunotherapy response. In the survival analysis, it was found that patients with higher TCRß clonality, lower TCRß evenness, higher TCRß Shannon diversity and lower TCRß convergence had higher overall survival (OS) and progression-free survival (PFS). However, no statistically significant association was observed. Regarding cytokines, those patients with higher levels of IL-2 and IL-15 presented statistically significantly shorter OS and PFS, respectively. In fact, in the multivariable analysis, the high IL-15 level increased the risk of death by three times. Although the sample size was small and more studies are needed to confirm our results, our study reveals promising markers of responses to ICIs.

Impact of antibiotics, corticosteroids, and microbiota on immunotherapy efficacy in patients with non-small cell lung cancer.

Lung cancer is a leading cause of morbidity and mortality globally, with its high mortality rate attributed mainly to non-small cell lung cancer (NSCLC). Although immunotherapy with immune checkpoint inhibitors (ICI) has revolutionized its treatment, patient response is highly variable and lacking predictive markers. We conducted a prospective study on 55 patients with NSCLC undergoing ICI therapy to identify predictive markers of both response and immune-related adverse events (IrAEs) in the airway microbiota. We also analyzed the clinical evolution and overall survival (OS) with respect to treatments that affect the integrity of the microbiota, such as antibiotics and corticosteroids. Our results demonstrated that respiratory microbiota differ significantly in ICI responders: they have higher alpha diversity values and lower abundance of the Firmicutes phylum and the Streptococcus genus. Employing a logistic regression model, the abundance of Gemella was the major predictor of non-ICI response, whereas Lachnoanaerobaculum was the best predictor of a positive response to ICI. The most relevant results were that antibiotic consumption is linked to a lower ICI response, and the use of corticosteroids correlated with poorer overall survival. Whereas previous studies have focused on gut microbiota, our findings highlight the importance of the respiratory microbiota in predicting the treatment response. Future research should explore microbiota modulation strategies to enhance immunotherapy outcomes. Understanding the impact of antibiotics, corticosteroids, and microbiota on NSCLC immunotherapy will help personalize treatment and improve patient outcomes.

Biomarkers of Immunotherapy Response in Patients with Non-Small-Cell Lung Cancer: Microbiota Composition, Short-Chain Fatty Acids, and Intestinal Permeability.

Immune checkpoint inhibitors have been proposed as the standard treatment for different stages of non-small-cell lung cancer in multiple indications. Not all patients benefit from these treatments, however, and certain patients develop immune-related adverse events. Although the search for predictors of response to these drugs is a major field of research, these issues have yet to be resolved. It has been postulated that microbiota could play a relevant role in conditioning the response to cancer treatments; however, the human factor of intestinal permeability also needs to be considered as it is closely related to the regulation of host-microbiota interaction. In this article, we analyzed the possible relationship between the response to immune checkpoint inhibitors and the onset of immune-related adverse events, gut microbiota status, and intestinal membrane permeability. In a pioneering step, we also measured short-chain fatty acid content in feces. Although the correlation analyses failed to identify predictive biomarkers, even when all variables were integrated, our patients' microbial gut ecosystems were rich and diverse, and the intestinal barrier's integrity was preserved. These results add new knowledge on the composition of microbiota and its correlation with barrier permeability and short-chain fatty acids and suggest that more studies are required before these potential biomarkers can be incorporated into the clinical management of patients via immune checkpoint inhibitor treatment.

A Subset of PD-1-Expressing CD56bright NK Cells Identifies Patients with Good Response to Immune Checkpoint Inhibitors in Lung Cancer.

(1) Despite the effectiveness of immune checkpoint inhibitors (ICIs) in lung cancer, there is a lack of knowledge about predictive biomarkers. The objective of our study is to analyze different subsets of T-lymphocytes and natural killer (NK) cells as predictive biomarkers in a cohort of patients with nonsmall cell lung cancer (NSCLC) treated with ICI. (2) This is an observational, prospective study with 55 NSCLC patients treated with ICI. A total of 43 T and NK cell subsets are analyzed in peripheral blood, including the main markers of exhaustion, differentiation, memory, activation, and inhibition. (3) Regarding the descriptive data, Granzyme B+CD4+ Treg lymphocytes stand out (median 17.4%), and within the NK populations, most patients presented cytotoxic NK cells (CD56+CD3-CD16+GranzymeB+; median 94.8%), and about half of them have highly differentiated adaptive-like NK cells (CD56+CD3-CD16+CD57+ (mean 59.8%). A statistically significant difference was observed between the expression of PD1 within the CD56bright NK cell subpopulation (CD56+CD3-CD16-PD-1+) (p = 0.047) and a better OS. (4) Circulating immune cell subpopulations are promising prognostic biomarkers for ICI. Pending on validation with a larger sample, here we provide an analysis of the major circulating T and NK cell subsets involved in cancer immunity, with promising results despite a small sample size.

Association between missense variants of uncertain significance in the CHEK2 gene and hereditary breast cancer: a cosegregation and bioinformatics analysis.

Inherited mutations in the CHEK2 gene have been associated with an increased lifetime risk of developing breast cancer (BC). We aim to identify in the study population the prevalence of mutations in the CHEK2 gene in diagnosed BC patients, evaluate the phenotypic characteristics of the tumor and family history, and predict the deleteriousness of the variants of uncertain significance (VUS). A genetic study was performed, from May 2016 to April 2020, in 396 patients diagnosed with BC at the University Hospital Lozano Blesa of Zaragoza, Spain. Patients with a genetic variant in the CHEK2 gene were selected for the study. We performed a descriptive analysis of the clinical variables, a bibliographic review of the variants, and a cosegregation study when possible. Moreover, an in-depth bioinformatics analysis of CHEK2 VUS was carried out. We identified nine genetic variants in the CHEK2 gene in 10 patients (two pathogenic variants and seven VUS). This supposes a prevalence of 0.75% and 1.77%, respectively. In all cases, there was a family history of BC in first- and/or second-degree relatives. We carried out a cosegregation study in two families, being positive in one of them. The bioinformatics analyses predicted the pathogenicity of six of the VUS. In conclusion, CHEK2 mutations have been associated with an increased risk for BC. This risk is well-established for foundation variants. However, the risk assessment for other variants is unclear. The incorporation of bioinformatics analysis provided supporting evidence of the pathogenicity of VUS.

Microbiota and Lung Cancer. Opportunities and Challenges for Improving Immunotherapy Efficacy.

The advances in molecular biology and the emergence of Next Generation Sequencing (NGS) have revealed that microbiome composition is closely related with health and disease, including cancer. This relationship affects different levels of cancer such as development, progression, and response to treatment including immunotherapy. The efficacy of immune checkpoint inhibitors (ICIs) may be influenced by the concomitant use of antibiotics before, during or shortly after treatment with ICIs. Nevertheless, the linking mechanism between microbiote, host immunity and cancer is not clear and the role of microbiota manipulation and analyses in cancer management has not been clinically validated yet. Regarding the use of microbiome as biomarker to predict ICI efficacy it has been recently shown that the use of biochemical serum markers to monitor intestinal permeability and loss of barrier integrity, like citrulline, could be useful to monitor microbiota changes and predict ICI efficacy. There are still many unknowns about the role of these components, their relationship with the microbiota, with the use of antibiotics and the response to immunotherapy. The next challenge in microbiome research will be to identify individual microbial species that causally affect lung cancer phenotypes and response to ICI and disentangle the underlying mechanisms. Thus, further analyses in patients with lung cancer receiving treatment with ICIs and its correlation with the composition of the microbiota in different organs including the respiratory tract, peripheral blood and intestinal tract could be useful to predict the efficacy of ICIs and its modulation with antibiotic use.

Intratumoral Versus Circulating Lymphoid Cells as Predictive Biomarkers in Lung Cancer Patients Treated with Immune Checkpoint Inhibitors: Is the Easiest Path the Best One?

The molecular and cell determinants that modulate immune checkpoint (ICI) efficacy in lung cancer are still not well understood. However, there is a necessity to select those patients that will most benefit from these new treatments. Recent studies suggest the presence and/or the relative balance of specific lymphoid cells in the tumor microenvironment (TEM) including the T cell (activated, memory, and regulatory) and NK cell (CD56dim/bright) subsets, and correlate with a better response to ICI. The analyses of these cell subsets in peripheral blood, as a more accessible and homogeneous sample, might facilitate clinical decisions concerning fast prediction of ICI efficacy. Despite recent studies suggesting that lymphoid circulating cells might correlate with ICI efficacy and toxicity, more analyses and investigation are required to confirm if circulating lymphoid cells are a relevant picture of the lung TME and could be instrumental as ICI response biomarkers. This short review is aimed to discuss the recent advances in this fast-growing field.

From Tumor Mutational Burden to Blood T Cell Receptor: Looking for the Best Predictive Biomarker in Lung Cancer Treated with Immunotherapy.

Despite therapeutic advances, lung cancer (LC) is one of the leading causes of cancer morbidity and mortality worldwide. Recently, the treatment of advanced LC has experienced important changes in survival benefit due to immune checkpoint inhibitors (ICIs). However, overall response rates (ORR) remain low in unselected patients and a large proportion of patients undergo disease progression in the first weeks of treatment. Therefore, there is a need of biomarkers to identify patients who will benefit from ICIs. The programmed cell death ligand 1 (PD-L1) expression has been the first biomarker developed. However, its use as a robust predictive biomarker has been limited due to the variability of techniques used, with different antibodies and thresholds. In this context, tumor mutational burden (TMB) has emerged as an additional powerful biomarker based on the observation of successful response to ICIs in solid tumors with high TMB. TMB can be defined as the total number of nonsynonymous mutations per DNA megabases being a mechanism generating neoantigens conditioning the tumor immunogenicity and response to ICIs. However, the latest data provide conflicting results regarding its role as a biomarker. Moreover, considering the results of the recent data, the use of peripheral blood T cell receptor (TCR) repertoire could be a new predictive biomarker. This review summarises recent findings describing the clinical utility of TMB and TCRß (TCRB) and concludes that immune, neontigen, and checkpoint targeted variables are required in combination for accurately identifying patients who most likely will benefit of ICIs.

Gemcitabine/capecitabine in patients with metastatic breast cancer pretreated with anthracyclines and taxanes.

PURPOSE: Gemcitabine and capecitabine are 2 anticancer drugs with a mechanism of action involving metabolism of pyrimidine nucleotides. Both are among the few agents active in patients with metastatic breast cancer (MBC) progressing after therapy with anthracyclines and taxanes. We have conducted a phase II trial of gemcitabine/capecitabine in patients with disease progression after treatment with anthracyclines and taxanes. PATIENTS AND METHODS: Treatment included gemcitabine 2000 mg/m2 on day 1 every 3 weeks and capecitabine 2500 mg/m2 daily (divided into 2 doses) on days 1-14 every 3 weeks; treatment was administered until disease progression or unacceptable toxicity was documented. All patients received concomitant oral pyridoxine 300 mg twice daily to prevent hand-foot syndrome (HFS). Of 39 patients treated, 33 had received previous treatment with anthracyclines, 6 had medical contraindication to anthracyclines, 35 had previously received taxanes, and 23 had received vinorelbine. Fourteen patients had previous high-dose chemotherapy with stem cell rescue and 5 had previously received trastuzumab. Patients were 31-79 years of age (median, 55 years) and, altogether, were given 386 courses of therapy (range, 1-36 courses per patient; median, 6 courses). RESULTS: Grade 3/4 toxicities included HFS (11 courses, 6 patients), stomatitis (6 courses, 2 patients), diarrhea (5 courses, 4 patients), anemia (5 courses, 2 patients), thrombocytopenia (5 courses, 2 patients), and neutropenia (1 course, 1 patient). Response rate (all 39 patients were evaluable) was 48.7% (partial response, n = 19; stable disease, n = 7; progressive disease, n = 13). Thirty-six patients died because of disease progression, and 3 are alive with progressive disease. Median follow-up was 26 months or until death. Median duration of response was 15 months (range, 3-26 months). Median time to disease progression was 5 months (range, 1-26 months). Median overall survival duration was 10 months (range, 1-37 months). CONCLUSION: In this cohort of patients heavily pretreated with anthracyclines and taxanes, the response rate to gemcitabine/capecitabine is encouraging, although response duration is limited.

Bluetongue virus serotype 1 outbreak in the Basque Country (Northern Spain) 2007-2008. Data support a primary vector windborne transport.

BACKGROUND: Bluetongue (BT) is a vector-borne disease of ruminants that has expanded its traditional global distribution in the last decade. Recently, BTV-1 emerged in Southern Spain and caused several outbreaks in livestock reaching the north of the country. The aim of this paper was to review the emergence of BTV-1 in the Basque Country (Northern Spain) during 2007 and 2008 analyzing the possibility that infected Culicoides were introduced into Basque Country by winds from the infected areas of Southern Spain. METHODOLOGY/PRINCIPAL FINDINGS: We use a complex HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model to draw wind roses and backward wind trajectories. The analysis of winds showed September 28 to October 2 as the only period for the introduction of infected midges in the Basque Country. These wind trajectories crossed through the areas affected by serotype 1 on those dates in the South of the Iberian Peninsula. Additionally meteorological data, including wind speed and humidity, and altitude along the trajectories showed suitable conditions for Culicoides survival and dispersion. CONCLUSIONS/SIGNIFICANCE: An active infection in medium-long distance regions, wind with suitable speed, altitude and trajectory, and appropriate weather can lead to outbreaks of BTV-1 by transport of Culicoides imicola, not only over the sea (as reported previously) but also over the land. This shows that an additional factor has to be taken into account for the control of the disease which is currently essentially based on the assumption that midges will only spread the virus in a series of short hops. Moreover, the epidemiological and serological data cannot rule out the involvement of other Culicoides species in the spread of the infection, especially at a local level.

Signaling pathways involved in liver injury and regeneration in rabbit hemorrhagic disease, an animal model of virally-induced fulminant hepatic failure.

Management of fulminant hepatic failure (FHF) continues to be one challenging problem, and experimental animal models resembling its clinical conditions are still needed. Rabbit hemorrhagic disease (RHD) fullfils many requirements of an animal model of FHF. This work investigated changes in MAPK, NF-kappaB, AP-1 and STAT pathways during RHD-induced liver injury. Rabbits were infected with 2 x 10(4) hemagglutination units of an RHD virus isolate. Apoptosis was documented by the presence of caspase-3 activity and substantial PARP proteolysis at 36 and 48 h postinfection (pi). Infection induced a marked and maintained expression of TNF-alpha from 12 h pi, while there was only a transitory increase in IL-6 expression. Expression of phosphorylated (p)-JNK, p-p38 and p-ERK1/2 was significantly elevated at 12 h pi. At 48 h pi p-JNK expression was maintained at a maximum level, while that of p-p38 returned to normality and there was no p-ERK1/2 expression. Activation of NF-kappaB and AP-1 and increased expression of VCAM-1 and COX-2 were observed. No significant changes were detected in activation of STAT1 and STAT3, while SOCS3 expression increased significantly. The current findings suggest that activation of JNK is an essential component in liver injury mediated by the RHD virus and that lack of activation of STAT3, probably mediated by SOCS3 over-expression, would contribute to the inhibition of the regenerative response. Data show the presence of molecular mechanisms contributing to liver damage and the lack of regeneration and they support the usefulness of this model to investigate novel therapeutical modalities in FHF.

Prognostic significance and diagnostic value of protein S-100 and tyrosinase in patients with malignant melanoma.

OBJECTIVES: The utility of many molecules as tumor markers in melanoma has been investigated with different results. The aims of this study was to compare the value of tyrosinase mRNA by reverse transcription polymerase chain reaction (RT-PCR) in peripheral blood and of serum S-100 protein in patients with melanoma at different stages of disease. METHODS: We have studied 90 peripheral blood samples corresponding to 90 patients that had been diagnosed with melanoma. The clinical staging at the time of blood sampling was performed according to the American Join Committee on Cancer guidelines. S-100 protein in serum was measured by enzyme-linked immunosorbent assay (normal range: 0-0.150 microg) and the presence of tyrosinase mRNA was assessed by RT-PCR. RESULTS: Median progression-free survival was 281 days for tyrosinase positive patients and it has not been reached for tyrosinase negative patients (P = 0.03). Median progression free survival was 213 days for patients with elevated serum S-100 and it has not been reached for patients with normal level of serum S-100 (P < 0.001). Median overall survival (OS) was 396 days for tyrosinase positive patients and it has not been reached for negative patients (P = 0.0096). Median OS was 282 days for patients with elevated serum S-100 and it has not been reached for patients with normal level of serum S-100 (P < 0.001). In a multivariate analysis, both markers have significant prognostic value for time to progression and for survival (chi(2) test). CONCLUSIONS: RT-PCR for tyrosinase mRNA and S-100 are significant prognostic factors for progression-free survival and OS in melanoma. S-100 has higher sensitivity and specificity than tyrosinase.

Contaminación parasitaria en heces de perros, recolectadas en calles de la ciudad de San Cristóbal de Las Casas, Chiapas, México / Parasitic contamination by dog feces collected from the streets of San Cristobal de Las Casas, Chiapas, Mexico

An analysis of canine faecal material collected in 13 different neighborhoods of the city of San Cristobal de Las Casas, Chiapas, Mexico, was carried out in order to know the frequency of contamination caused by Toxocara canis and other canine parasites. A total of 200 samples from streets, a traffic refuge and a park of the chosen neighborhoods in the city, were examined using the zinc sulphate method. Evidence of parasites was found in 37% (n = 74) of the samples. The frequency of I canis eggs was found to be 19 %, and that of Ancylostoma caninum eggs 18.5%; the oocistes of Isospora canis represented 2.5%. These results indicate that contamination of the soil of San Cristobal de Las Casas with these parasites, presents both a latent health risk for the population and visitors of this city, besides the poor image fecal contamination gives to national and foreign tourists.

Se realizó un estudio de materia fecal de perros en 13 barrios de la ciudad de San Cristóbal de Las Casas, Chiapas, México, para conocer la frecuencia de recontaminación causada por Toxocara canis y otros parásitos caninos. Se examinaron con el método de sulfato de zinc 200 muestras de materia fecal recolectadas en diferentes calles, un camellón y un parque de los barrios seleccionados en la ciudad. Se detectaron formas parasitarias en 37% (n = 74) de las muestras. La frecuencia de huevos de T. canis fue de 19.0% y la de Ancylostoma caninum, de 18.5%; la de ooquistes de Isospora canis de 2.5%. Los resultados indican que la contaminación de los suelos de la ciudad de San Cristóbal de Las Casas con parásitos de cánidos es un riesgo latente para la salud de los habitantes y visitantes de esta ciudad, además de la desagradable imagen que el fecalismo ofrece al turismo nacional y extranjero.