Metformin induces ZFP36 by mTORC1 inhibition in cervical cancer-derived cell lines.

BACKGROUND: Metformin, a widely prescribed antidiabetic drug, has shown several promising effects for cancer treatment. These effects have been shown to be mediated by dual modulation of the AMPK-mTORC1 axis, where AMPK acts upstream of mTORC1 to decrease its activity. Nevertheless, alternative pathways have been recently discovered suggesting that metformin can act through of different targets regulation. METHODS: We performed a transcriptome screening analysis using HeLa xenograft tumors generated in NOD-SCID mice treated with or without metformin to examine genes regulated by metformin. Western Blot analysis, Immunohistochemical staining, and RT-qPCR were used to confirm alterations in gene expression. The TNMplot and GEPIA2 platform were used for in silico analysis of genes found up-regulated by metformin, in cervical cancer patients. We performed an AMPK knock-down using AMPK-targeted siRNAs and mTOR inhibition with rapamycin to investigate the molecular mechanisms underlying the effect of metformin in cervical cancer cell lines. RESULTS: We shown that metformin decreases tumor growth and increased the expression of a group of antitumoral genes involved in DNA-binding transcription activator activity, hormonal response, and Dcp1-Dcp2 mRNA-decapping complex. We demonstrated that ZFP36 could act as a new molecular target increased by metformin. mTORC1 inhibition using rapamycin induces ZFP36 expression, which could suggest that metformin increases ZFP36 expression and requires mTORC1 inhibition for such effect. Surprisingly, in HeLa cells AMPK inhibition did not affect ZFP36 expression, suggesting that additional signal transducers related to suppressing mTORC1 activity, could be involved. CONCLUSIONS: These results highlight the importance of ZFP36 activation in response to metformin treatment involving mTORC1 inhibition.

Tumor microenvironment differences between primary tumor and brain metastases.

The present review aimed to discuss contemporary scientific literature involving differences between the tumor microenvironment (TME) in melanoma, lung cancer, and breast cancer in their primary site and TME in brain metastases (BM). TME plays a fundamental role in the behavior of cancer. In the process of carcinogenesis, cells such as fibroblasts, macrophages, endothelial cells, natural killer cells, and other cells can perpetuate and progress carcinogenesis via the secretion of molecules. Oxygen concentration, growth factors, and receptors in TME initiate angiogenesis and are examples of the importance of microenvironmental conditions in the performance of neoplastic cells. The most frequent malignant brain tumors are metastatic in origin and primarily originate from lung cancer, breast cancer, and melanoma. Metastatic cancer cells have to adhere to and penetrate the blood-brain barrier (BBB). After traversing BBB, these cells have to survive by producing various cytokines, chemokines, and mediators to modify their new TME. The microenvironment of these metastases is currently being studied owing to the discovery of new therapeutic targets. In these three types of tumors, treatment is more effective in the primary tumor than in BM due to several factors, including BBB. Understanding the differences in the characteristics of the microenvironment surrounding the primary tumor and their respective metastasis might help improve strategies to comprehend cancer.

Molecular iodine inhibits the expression of stemness markers on cancer stem-like cells of established cell lines derived from cervical cancer.

BACKGROUND: Cancer stem cells (CSC) are characterized by deregulated self-renewal, tumorigenicity, metastatic potential, aberrant stemness signaling pathways, resistance to conventional therapy, and the ability to give rise to a progeny of proliferating cells that constitute the bulk of tumors. Targeting CSC will provide novel treatments for cancer. Different investigations have focused on developing complementary approaches that involve natural compounds that decrease chemo-resistance and reduce the side effects of conventional therapies. Since, it has been reported that molecular iodine (I2) exhibits antineoplastic effects and decreases tumor progression in some cancer models, we evaluated the potential effect of I2 on cell cultures enriched in cervical cancer stem-like cells. METHODS: HeLa and SiHa cervical cancer cells were treated with 200uM I2 for 24 h. After time, cells were cultured in CSC-conditioned medium (cervospheres) and viability assays were performed. Following, tumorigenic capabilities in cervospheres treated with I2 were evaluated in NOD/SCID mice. HeLa monolayer cells untreated and their respective cervosphere cells treated or untreated with 200 µM of I2 for 24 h were xenotransplanted subcutaneously at different amounts and mice were monitored for at least 2 months. RESULTS: In the present study, monolayer and CSC-enriched cultures (cervospheres) from cervical cancer-derived cell lines, HeLa and SiHa, showed that 200uM I2 supplementation inhibits proliferation of both and decreased their tumorigenic capacity, in vivo. This antineoplastic effect of I2 was accompanied by diminished expression of stemness markers including CD49f, CK17, OCT-4, NANOG, SOX2, and KLF4, as well as increased expression and activation of PPARγ receptors. CONCLUSIONS: All this data led us to suggest a clinical potential use of I2 for targeting CSC and improve current treatments against cervical cancer.

Regulation of Cellular Metabolism by High-Risk Human Papillomaviruses.

The alteration of glucose metabolism is one of the first biochemical characteristics associated with cancer cells since most of these cells increase glucose consumption and glycolytic rates even in the presence of oxygen, which has been called “aerobic glycolysis" or the Warburg effect. Human papillomavirus (HPV) is associated with approximately 5% of all human cancers worldwide, principally to cervical cancer. E6 and E7 are the main viral oncoproteins which are required to preserve the malignant phenotype. These viral proteins regulate the cell cycle through their interaction with tumor suppressor proteins p53 and pRB, respectively. Together with the viral proteins E5 and E2, E6 and E7 can favor the Warburg effect and contribute to radio- and chemoresistance through the increase in the activity of glycolytic enzymes, as well as the inhibition of the Krebs cycle and the respiratory chain. These processes lead to a fast production of ATP obtained by Warburg, which could help satisfy the high energy demands of cancer cells during proliferation. In this way HPV proteins could promote cancer hallmarks. However, it is also possible that during an early HPV infection, the Warburg effect could help in the achievement of an efficient viral replication.

Side populations from cervical-cancer-derived cell lines have stem-cell-like properties.

The target cells for the transforming mutations caused by high-risk human papillomavirus (HPV) infection could be the stem cells of the uterine cervical epithelium, generating particular cancer stem cells (CSCs). The aim of this study was to identify and characterize the CSCs from cervical-cancer-derived cell lines. The ability of SiHa, CaLo, and C-33A cell lines to efflux Hoechst 33342 was evaluated by flow cytometry and cells from the corresponding side populations (SPs) and nonside populations (NSPs) were analyzed for their cell-cycle status (pyronin Y) and their mRNA levels of ABC transporter family members (with qPCR). Specific markers (α6-integrin(bri)/CD71(dim), CK17) of normal epithelial stem cells were evaluated by flow cytometry. The biological properties of these cells were analyzed, including their colony heterogeneity, repopulation, and anchorage-independent colony formation. We identified SPs (around 3 %) in the SiHa and CaLo cell lines, more than 70 % of which were in G0 phase and strongly expressed ABC transporters (predominantly ABCG2 and ABCB1). The SP from CaLo cells showed an α6-integrin(bri)/CD(dim) pattern, whereas the SP from the SiHa cells showed an α6-integrin(-)/CD(dim) pattern. Recultured cells from the SPs of both cell lines generated both SPs and NSPs, and had higher clonogenic potential to form mainly holoclones and greater colony-forming efficiency under anchorage-independent growth conditions than the cells from the NSPs or total cell populations. Interestingly, we identified no SP in the HPV-uninfected C-33A cell line, and it did not express ABCG2 or other members of the ABC transporters (ABCB1, ABCC1, or ABCA3).

Cancer stem cell markers: Symphonic masters of chemoresistance and immune evasion.

Cancer Stem Cells (CSCs) are highly tumorigenic, chemoresistant, and immune evasive. They emerge as a central driver that gives rise to the bulk of tumoral mass, modifies the tumor microenvironment (TME), and exploits it, leading to poor clinical outcomes for patients with cancer. The existence of CSCs thus accounts for the failure of conventional therapies and immune surveillance. Identifying CSCs in solid tumors remains a significant challenge in modern oncology, with the use of cell surface markers being the primary strategy for studying, isolating, and enriching these cells. In this review, we explore CSC markers, focusing on the underlying signaling pathways that drive CSC self-renewal, which simultaneously makes them intrinsically chemoresistant and immune system evaders. We comprehensively discuss the autonomous and non-autonomous functions of CSCs, with particular emphasis on their interactions with the tumor microenvironment, especially immune cells. This reciprocal network enhances CSCs malignancy while compromising the surrounding niche, ultimately defining therapeutic vulnerabilities associated with each CSC marker. The most common CSCs surface markers addressed in this review-CD44, CD133, ICAM1/CD54, and LGR5-provide insights into the interplay between chemoresistance and immune evasion, two critically important phenomena in disease eradication. This new perspective on the state-of-the-art of CSCs will undoubtedly open new avenues for therapy.

Compounds Consisting of Quinazoline, Ibuprofen, and Amino Acids with Cytotoxic and Anti-Inflammatory Effects.

In this research work, a series of 16 quinazoline derivatives bearing ibuprofen and an amino acid were designed as inhibitors of epidermal growth factor receptor tyrosine kinase domain (EGFR-TKD) and cyclooxygenase-2 (COX-2) with the intention of presenting dual action in their biological behavior. The designed compounds were synthesized and assessed for cytotoxicity on epithelial cancer cells lines (AGS, A-431, MCF-7, MDA-MB-231) and epithelial non-tumorigenic cell line (HaCaT). From this evaluation, derivative 6 was observed to exhibit higher cytotoxic potency (IC50) than gefitinib (reference drug) on three cancer cell lines (0.034 µM in A-431, 2.67 µM in MCF-7, and 3.64 µM in AGS) without showing activity on the non-tumorigenic cell line (>100 µM). Furthermore, assessment of EGFR-TKD inhibition by 6 showed a discreet difference compared to gefitinib. Additionally, 6 was used to conduct an in vivo anti-inflammatory assay using the 12-O-tetradecanoylphorbol-3-acetate (TPA) method, and it was shown to be 5 times more potent than ibuprofen. Molecular dynamics studies of EGFR-TKD revealed interactions between compound 6 and M793. On the other hand, one significant interaction was observed for COX-2, involving S531. The RMSD graph indicated that the ligand remained stable in 50 ns.

Circulating Gastric Cancer Stem Cells as Blood Screening and Prognosis Factor in Gastric Cancer.

Gastric cancer (GC) is the fourth leading cause of cancer-related death, associated with late diagnosis and treatment resistance. Currently, screening tests for GC are not cost-effective or have low accuracy. Previously, we described an extended phenotype of gastric cancer stem cells (GCSCs; CD24+CD44+CD54+EpCAM+) that is associated with metastasis and tumor stage in GC patients. The goal of the current research is to evaluate the presence of these GCSCs in the peripheral blood of GC patients and healthy volunteers. A total of 73 blood samples were collected from 32 GC patients and 41 healthy volunteers. After peripheral blood mononuclear cell (PBMC) extraction, multiparametric flow cytometry was performed looking for GCSCs. Using clustering data through artificial intelligence (AI), we defined high/low levels of circulating GCSCs (cGCSCs) and proceeded to evaluate its association with clinical and prognostic variables. Finally, a diagnostic test analysis was performed evaluating patients and healthy volunteers. We found that cGCSCs are present in most GC patients with a mean concentration of 0.48%. The AI clustering showed two groups with different cGCSC levels and clinical characteristics. Through statistical analysis, we confirmed the association between cGCSC levels and lymph node metastasis, distant metastasis, and overall survival. The diagnostic test analysis showed sensibility, specificity, and area under the curve (AUC) of 83%, 95%, and 0.911, respectively. Our results suggest that the assessment of cGCSCs CD24+CD44+CD54+EpCAM+ could be a potential noninvasive test, with prognostic value, as well as highly sensitive and specific for screening or diagnosis of GC; however, a larger scale study will be necessary to confirm this.

Peripherical Blood hsa-miR-335-5p Quantification as a Prognostic, but Not Diagnostic, Marker of Gastric Cancer.

Gastric cancer (GC) is a leading cause of death, and this pathology often receives a diagnosis in an advanced stage. The development of a less invasive and cost-effective test for detection is essential for decreasing the mortality rate and increasing the life expectancy of GC patients. We evaluated the potential targeting of CD54/ICAM1, a marker of gastric cancer stem cells, with miRNAs to detect GC in blood samples. The analyses included 79 blood samples, 38 from GC patients and 41 from healthy donors, who attended INCan, México City. The total RNA was obtained from the blood plasma, and RT-PCR and qPCR were performed to obtain the relative expression of each miRNA. Hsa-miR-335-5p was detected in the plasma of GC patients and healthy donors at the same levels. The ROC curve analyses indicated that this miRNA was not a candidate for the molecular diagnosis of GC. We did not observe a correlation between the expression of hsa-miR-335-5p and clinical variables; however, the Kaplan-Meier analyses indicated that, in patients who survived more than 12 months, a lower expression of hsa-miR-335-5p was correlated with a better prognosis. It would be convenient to evaluate a larger panel of miRNAs, including miRNAs expressed in a limited number of cell types or with a low number targets, to obtain more specific candidates for developing a robust test for the diagnosis/prognosis of GC.

miR-218-5p, miR-124-3p and miR-23b-3p act synergistically to modulate the expression of NACC1, proliferation, and apoptosis in C-33A and CaSki cells.

Background: In cervical cancer (CC), miR-218-5p, -124-3p, and -23b-3p act as tumor suppressors. These miRNAs have specific and common target genes that modulate apoptosis, proliferation, invasion, and migration; biological processes involved in cancer. Methods: miR-218-5p, -124-3p, and -23b-3p mimics were transfected into C-33A and CaSki cells, and RT-qPCR was used to quantify the level of each miRNA and NACC1. Proliferation was assessed by BrdU and apoptosis by Annexin V/PI. In the TCGA and The Human Protein Atlas databases, the level of NACC1 mRNA and protein (putative target of the three miRNAs) was analyzed in CC and normal tissue. The relationship of NACC1 with the overall survival in CC was analyzed in GEPIA2. NACC1 mRNA and protein levels were higher in CC tissues compared with cervical tissue without injury. Results: An increased expression of NACC1 was associated with lower overall survival in CC patients. The levels of miR-218-5p, -124-3p, and -23b-3p were lower, and NACC1 was higher in C-33A and CaSki cells compared to HaCaT cells. The increase of miR-218-5p, -124-3p, and -23b-3p induced a significant decrease in NACC1 mRNA. The transfection of the three miRNAs together caused more drastic changes in the level of NACC1, in the proliferation, and in the apoptosis with respect to the individual transfections of each miRNA. Conclusion: The results indicate that miR-218-5p, -124-3p, and -23b-3p act synergistically to decrease NACC1 expression and proliferation while promoting apoptosis in C-33A and CaSki cells. The levels of NACC1, miR-218-5p, -124-3p, and -23b-3p may be a potential prognostic indicator in CC.

A novel IgE antibody targeting the prostate-specific antigen as a potential prostate cancer therapy.

BACKGROUND: Prostate cancer (PCa) is the second leading cause of cancer deaths in men in the United States. The prostate-specific antigen (PSA), often found at high levels in the serum of PCa patients, has been used as a marker for PCa detection and as a target of immunotherapy. The murine IgG1 monoclonal antibody AR47.47, specific for human PSA, has been shown to enhance antigen presentation by human dendritic cells and induce both CD4 and CD8 T-cell activation when complexed with PSA. In this study, we explored the properties of a novel mouse/human chimeric anti-PSA IgE containing the variable regions of AR47.47 as a potential therapy for PCa. Our goal was to take advantage of the unique properties of IgE in order to trigger immune activation against PCa. METHODS: Binding characteristics of the antibody were determined by ELISA and flow cytometry. In vitro degranulation was determined by the release of ß-hexosaminidase from effector cells. In vivo degranulation was monitored in human FcεRIα transgenic mice using the passive cutaneous anaphylaxis assay. These mice were also used for a vaccination study to determine the in vivo anti-cancer effects of this antibody. Significant differences in survival were determined using the Log Rank test. In vitro T-cell activation was studied using human dendritic cells and autologous T cells. RESULTS: The anti-PSA IgE, expressed in murine myeloma cells, is properly assembled and secreted, and binds the antigen and FcεRI. In addition, this antibody is capable of triggering effector cell degranulation in vitro and in vivo when artificially cross-linked, but not in the presence of the natural soluble antigen, suggesting that such an interaction will not trigger systemic anaphylaxis. Importantly, the anti-PSA IgE combined with PSA also triggers immune activation in vitro and in vivo and significantly prolongs the survival of human FcεRIα transgenic mice challenged with PSA-expressing tumors in a prophylactic vaccination setting. CONCLUSIONS: The anti-PSA IgE exhibits the expected biological properties and is capable of triggering immune activation and anti-tumor protection. Further studies on this antibody as a potential PCa therapy are warranted.

Differences in efficacy and safety among CAR-Ts anti-CD19/CD22, anti-CD19, and anti-CD22, in adult patients with relapse/refractory B-cell acute lymphoblastic leukemia: a meta-analysis and systematic review.

Relapsed/refractory B-cell acute lymphoblastic leukemia (R/R B-ALL) is a challenging disease with low rates of remission and survival in adult patients. Anti-CD19 Chimeric Antigen Receptor T-cells (CAR-Ts) therapies have been approved for these patients. Dual-target CAR-Ts against CD19 and CD22 have recently been developed to improve the efficacy of the single-target therapy; however, extent of the improvement using this dual-target therapy has yet to be determined. We performed a meta-analysis of the outcome and safety of CAR-Ts, comparing anti-CD19 vs anti-CD22 vs dual-target anti-CD19/CD22 CAR-Ts, to elucidate the differences and limitations of these therapies in adult patients with R/R B-ALL. Although the limitations of our study derived from heterogeneity in the included publications, our results suggest that anti-CD19/CD22 CAR-Ts generate lower incidence of relapse and neurotoxicity, but similar results were obtained regarding complete remission, minimal residual disease, overall survival, and cytokine release syndrome compared with single-target anti-CD19 and anti-CD22 CAR-Ts.

Mutant p53 gain-of-function stimulates canonical Wnt signaling via PI3K/AKT pathway in colon cancer.

Aberrant canonical Wnt signaling is a hallmark of colon cancer. The TP53 tumor suppressor gene is altered in many solid tumors, including colorectal cancer, resulting in mutant versions of p53 (mut-p53) that lose their tumor suppressor capacities and acquire new-oncogenic functions (GOFs) critical for disease progression. Although the mechanisms related to mut-p53 GOF have been explored extensively, the relevance of mut-p53 in the canonical Wnt pathway is not well defined. This work investigated the influence of mut-p53 compared to wt-p53 in ß-catenin-dependent Wnt signaling. Using the TCGA public data from Pan-Cancer and the GEPIA2 platform, an in silico analysis of wt-p53 versus mut-p53 genotyped colorectal cancer patients showed that TP53 (p53) and CTNNB1 (ß-catenin) are significantly overexpressed in colorectal cancer, compared with normal tissue. Using p53 overexpression or p53 knockdown assays of wt-p53 or mut-p53, we found that while wt-p53 antagonizes canonical Wnt signaling, mut-p53 induces the opposite effect, improving the ß-catenin-dependent transcriptional activity and colony formation ability of colon cancer cells, which were both decreased by mut-p53 knockdown expression. The mechanism involved in mut-p53-induced activation of canonical Wnt appears to be via AKT-mediated phosphorylation of Ser 552 of ß-catenin, which is known to stabilize and enhance its transcriptional activity. We also found that while wt-p53 expression contributes to 5-FU sensitivity in colon cancer cells, the RITA p53 reactivating molecule counteracted the resistance against 5-FU in cells expressing mut-p53. Our results indicate that mut-p53 GOF acts as a positive regulator of canonical Wnt signaling and participates in the induction of resistance to 5-FU in colon cancer cells.

CD24+CD44+CD54+EpCAM+ gastric cancer stem cells predict tumor progression and metastasis: clinical and experimental evidence.

BACKGROUND: Gastric cancer (GC) is a leading cause of cancer-related deaths worldwide. Specific and thorough identification of cancer cell subsets with higher tumorigenicity and chemoresistance, such as cancer stem cells (CSCs), could lead to the development of new and promising therapeutic targets. For better CSC identification, a complete or extended surface marker phenotype is needed to provide increased specificity for new cell targeting approaches. Our goal is to identify and characterize a putative extended phenotype for CSCs derived from patients with GC before treatment, as well as to evaluate its clinical value. In addition, we aim to ensure that cells with this phenotype have stemness and self-renewal capabilities. METHODS: This is a cohort study including 127 treatment-naïve patients with GC who attended the Instituto Nacional de Cancerología. Multiparametric flow cytometry analysis was performed to determine the extended phenotype of cells derived from gastric biopsies. The tumorigenic capability of cells identified in patients was assessed in a zebrafish model. RESULTS: CD24+CD44+CD54+EpCAM+ cells were present in all treatment-naïve patients included, with a median abundance of 1.16% (0.57-1.89%). The percentage of CD24+CD44+CD54+EpCAM+ cells was categorized as high or low using 1.19% as the cutoff for the CD24+CD44+CD54+EpCAM+ cell subset. Additionally, a higher TNM stage correlated with a higher percentage of CD24+CD44+CD54+EpCAM+ cells (Rho coefficient 0.369; p < 0.0001). We also demonstrated that a higher percentage of CD24+CD44+CD54+EpCAM+ cells was positively associated with metastasis. The metastatic potential of these cells was confirmed in a zebrafish model. Ultimately, under our conditions, we conclude that CD24+CD44+CD54+EpCAM+ cells are true gastric cancer stem cells (GCSCs). CONCLUSION: The CD24+CD44+CD54+EpCAM+ cells present in tissue samples from patients are true GCSCs. This extended phenotype results in better and more specific characterization of these highly tumorigenic cells. The relative quantification of CD24+CD44+CD54+EpCAM+ cells has potential clinical value, as these cells are associated with metastatic disease, making their presence an additional prognostic marker and possibly a target for the design of new antineoplastic treatments in the era of precision oncology. Overall, the extended CD24+CD44+CD54+EpCAM+ phenotype of GCSCs could support their isolation for the study of their stemness mechanisms, leading to the identification of better molecular targets for the development of both new therapeutic approaches such as oncoimmunotherapy and new diagnostic and clinical prognostic strategies for GC.

New insights into the interactions of HPV-16 E6*I and E6*II with p53 isoforms and induction of apoptosis in cancer-derived cell lines.

An important characteristic of cancers associated with high-risk human papillomaviruses (HR-HPV) is the inability of p53 to activate apoptosis due to the effect of the oncoprotein E6. However, the effect of HPV-16 E6 splice variant isoforms (namely E6*I and E6*II), their interaction with the existing p53 isoforms, and their influence on apoptosis is unclear. Here, we report the outcome of ectopic expression of HPV-16 E6, E6*I, and E6*II on the relative levels of p53 and p53 isoforms Δ40p53 and Δ133p53 and their interactions with these proteins. Additionally, we evaluated the effect of ectopic expression of p53, Δ40p53, and Δ133p53 on apoptosis in a p53 null pulmonary cell line (H1299) co-transfected with E6 isoforms and p53+/+ cell lines with HR-HPV (SiHa and HeLa), transfected with p53 isoforms and treated with cisplatin, a conventional drug used to treat cervical cancer. Our results show that E6 and E6*II induced a significant decrease in p53, but only E6 triggered a Δ40p53 decrease and that E6*II interacts with p53 but not with Δ40p53 and Δ133p53. On the other hand, E6*I did not show any effect or interaction with the p53 isoforms. We found that apoptosis was elevated in H1299 cells transfected with p53 (p = 0.0001) and Δ40p53 (p = 0.0001). A weak apoptotic effect was observed when Δ133p53 was ectopically expressed (p = 0.0195). We observed that both p53 (p = 0.0006) and Δ40p53 (p = 0.0014) induced apoptosis in cisplatin-treated SiHa cells; however in cisplatin-treated HeLa cells, only p53 induced apoptosis (p = 0.0029). No significant differences in apoptosis were observed upon ectopic expression of p53, Δ40p53, and Δ133p53 in SiHa and HeLa cells. Our findings suggest a possible therapeutic application for the combining of p53 or Δ40p53 with cisplatin to induce an increased apoptosis of cancer cells expressing E6 isoforms from HPV-16.

Acupuncture May Stimulate Anticancer Immunity via Activation of Natural Killer Cells.

This article presents the hypothesis that acupuncture enhances anticancer immune functions by stimulating natural killer (NK) cells. It provides background information on acupuncture, summarizes the current scientific understanding of the mechanisms through which NK cells act to eliminate cancer cells, and reviews evidence that acupuncture is associated with increases in NK cell quantity and function in both animals and humans. The key contribution of this article involves the use of cellular immunology and molecular biological theory to interpret and synthesize evidence from disparate animal and human studies in formulating the 'acupuncture immuno-enhancement hypothesis': clinicians may use acupuncture to promote the induction and secretion of NK-cell activating cytokines that engage specific NK cell receptors that endogenously enhance anticancer immune function.

The cross talk between gastric cancer stem cells and the immune microenvironment: a tumor-promoting factor.

Cross talk between cancer cells and the immune system is determinant for cancer progression. Emerging evidence demonstrates that GC characteristics such as metastasis, treatment resistance, and disease recurrence are associated with a tumor subpopulation called gastric cancer stem cells (GCSCs). However, the specific interaction between GCSCs and the immune microenvironment is still under investigation. Although immune evasion has been well described for cancer stem cells (CSCs), recent studies show that GCSCs can also regulate the immune system and even benefit from it. This review will provide an overview of bidirectional interactions between CSCs and immune cells in GC, compiling relevant data about how CSCs can induce leukocyte reprogramming, resulting in pro-tumoral immune cells that orchestrate promotion of metastasis, chemoresistance, tumorigenicity, and even increase in number of cancer cells with stem properties. Some immune cells studied are tumor-associated macrophages (TAMs), neutrophils, Th17 and T regulatory (Treg) cells, mesenchymal stem cells (MSCs), and cancer-associated fibroblasts (CAFs), as well as the signaling pathways involved in these pro-tumoral activities. Conversely, although there are cytotoxic leukocytes that can potentially eliminate GCSCs, we describe mechanisms for immune evasion in GCSCs and their clinical implications. Furthermore, we describe current available immunotherapy targeting GCSC-related markers as possible treatment for GC, discussing how the CSC-modified immune microenvironment can mitigate or inactivate these immunotherapies, limiting their effectiveness. Finally, we summarize key concepts and relevant evidence to understand the cross talk between GCSCs and the immune microenvironment as an important process for effective design of therapies against GCSCs that improve the outcome of patients with GC.

Anti-inflammatory and antitumor activities of the chloroform extract and anti-inflammatory effect of the three diterpenes isolated from Salvia ballotiflora Benth.

BACKGROUND: Drugs used for the treatment of diseases associated with chronic inflammation, such as cancer and rheumatoid arthritis have the potential to cause undesirable side-effects, which might result in patients ending treatment prematurely. However, plants are a viable option for the treatment of inflammatory diseases. In this study, we assessed the in vivo and in vitro anti-inflammatory activity, and the antitumor effects of the chloroform extract of Salvia ballotiflora (ECL). The pro-apoptotic effects of ECL in CT26 cells were also determined. METHODS: The chloroform extract of Salvia ballotiflora (ECL) was standardized using 19-deoxyicetexone (DEOX) as a phytochemical marker. The anti-inflammatory activity of ECL was determined on acute and chronic inflammatory models using the TPA-induced mouse ear edema assay. The antitumor activity of ECL was evaluated by the subcutaneous inoculation of CT26 cells on the back of Balb/c mice. In vitro CT26 cell death induced by ECL was determined by Annexin V/propidium iodide staining assay using flow cytometry. ECL and the diterpenes isolated from the chloroform extract included 19-deoxyicetexone (DEOX), icetexone (ICT), and 7,20-dihydroanastomosine (DAM), which were tested in LPS-stimulated J774A.1 macrophages to quantify pro-inflammatory cytokine levels. The in vitro anti-arthritic activity of ECL was determined using the bovine serum protein (BSP) denaturation assay. RESULTS: ECL exerted anti-inflammatory activities in acute (84% of inhibition, 2 mg/ear) and chronic models (62.71%, at 100 mg/kg). ECL showed antitumor activity at 200 mg/kg and 300 mg/kg, reducing tumor volume by 30 and 40%, respectively. ECL (9.5 µg/mL) induced in vitro apoptosis in CT26 cells by 29.1% (48 h of treatment) and 93.9% (72 h of treatment). ECL (10 µg/ml) decreased levels of NO (53.7%), pro-inflammatory cytokines IL-6 (44.9%), IL-1ß (71.9%), and TNF-α (40.1%), but increased the production of the anti-inflammatory cytokine IL-10 (44%). The diterpenes DEOX, ICT, and DAM decreased levels of NO (38.34, 47.63, 67.15%), IL-6 (57.84, 60.45, 44.26%), and TNF-α (38.90, 31.30, 32.83%), respectively. ECL showed in vitro antiarthritic activity (IC50 = 482.65 µg/mL). CONCLUSIONS: ECL exhibited anti-inflammatory and anti-tumor activities. Furthermore, the diterpenes DEOX, DAM, and ICT showed anti-inflammatory activity by reducing levels of NO, TNF-α, and IL-6.

Bispecific CAR T Cells against EpCAM and Inducible ICAM-1 Overcome Antigen Heterogeneity and Generate Superior Antitumor Responses.

Adoptive transfer of chimeric antigen receptor (CAR) T cells has demonstrated unparalleled responses in hematologic cancers, yet antigen escape and tumor relapse occur frequently. CAR T-cell therapy for patients with solid tumors faces even greater challenges due to the immunosuppressive tumor environment and antigen heterogeneity. Here, we developed a bispecific CAR to simultaneously target epithelial cell adhesion molecule (EpCAM) and intercellular adhesion molecule 1 (ICAM-1) to overcome antigen escape and to improve the durability of tumor responses. ICAM-1 is an adhesion molecule inducible by inflammatory cytokines and elevated in many types of tumors. Our study demonstrates superior efficacy of bispecific CAR T cells compared with CAR T cells targeting a single primary antigen. Bispecific CAR T achieved more durable antitumor responses in tumor models with either homogenous or heterogenous expression of EpCAM. We also showed that the activation of CAR T cells against EpCAM in tumors led to upregulation of ICAM-1, which rendered tumors more susceptible to ICAM-1 targeting by bispecific CAR T cells. Our strategy of additional targeting of ICAM-1 may have broad applications in augmenting the activity of CAR T cells against primary tumor antigens that are prone to antigen loss or downregulation.

Regulation of anti-tumorigenic pathways by the combinatory treatment of calcitriol and TGF-ß in PC-3 and DU145 cells.

Calcitriol and transforming growth factors beta (TGF-ß) are involved in several biological pathways such as cell proliferation, differentiation, migration and invasion. Their cellular effects could be similar or opposite depending on the genetic target, cell type and context. Despite the reported association of calcitriol deficiency and disruption of the TGF-ß pathway in prostate cancer and the well-known independent effects of calcitriol and TGF-ßs on cancer cells, there is limited information regarding the cellular effects of calcitriol and TGF-ß in combination. In this study, we in vitro analyze the combinatory effects of calcitriol and TGF-ß on cell growth and apoptosis using PC-3 and DU145 human prostate cancer cell lines. Using high-throughput microarray profiling of PC-3 cells upon independent and combinatory treatments, we identified distinct transcriptional landscapes of each intervention, with a higher effect established by the combinatorial treatment, following by TGF-ß1 and later by calcitriol. A set of genes and enriched pathways converge among the treatments, mainly between the combinatory scheme and TGF-ß1, but the majority were treatment-specific. Of note, CYP24A1, IGFBP3, CDKN1A, NOX4 and UBE2D3 were significantly up-regulated upon the combinatorial treatment whereas CCNA1, members of the CT45A and APOBEC3 family were down-regulated. By public RNA signatures, we were able to confirm the regulation by the co-treatment over cell proliferation and cell cycle. We finally investigated the possible clinical impact of genes modulated by the combinatorial treatment using benchmark prostate cancer data. This comprehensive analysis reveals that the combinatory treatment impairs cell growth without affecting apoptosis and their combinatory actions might synergize and improved their individual effects to reprogram prostate cancer signaling.