Differential expression of cytokines and receptor expression during anoxic growth

HIF-1α Mediates Immunosuppression and Chemoresistance in Colorectal Cancer by Inhibiting CXCL9, -10 and -11

Uncertainty exists regarding the mechanisms by which hypoxia-inducible factors (HIFs) control CD8+T-cell migration into tumor microenvironments. Here, we found that HIF-1α knockdown or overexpression resulted in increased or decreased CXCL9, -10, and -11 expression in vitro, respectively. Gene Set Variation Analysis revealed that elevated HIF-1α levels correlated with a poor prognosis, severe pathological stage, and an absence of CD8+ T cells in the tumor microenvironment in colorectal cancer (CRC) patients. HIF-1α was inversely associated with pathways beneficial to anti-tumor immunotherapy and cytokine/chemokine function. In vivo, inhibiting HIF-1α or its upstream regulator BIRC2 significantly suppressed tumor growth and promoted CD8+ T-cell infiltration. CXCR3 neutralizing antibodies reversed these effects, implicating the involvement of CXCL9, -10, and -11/CXCR3 axis. The presence of HIF-1α weakened the upregulation of CXCL9, -10, and -11 by bleomycin and doxorubicin. Combining HIF-1α inhibition with bleomycin promoted CD8+ T-cell infiltration and tumor suppression in vivo. Moreover, doxorubicin could upregulate CXCL9, -10 and -11 by suppressing HIF-1α. Our findings highlight the potential of HIF-1α inhibition to improve CRC microenvironments and increase chemotherapy sensitivity.

The Effect of G. applanatum Crude Polysaccharide Extract on Proinflammatory Cytokines and Proapoptotic Caspases in HeLa Cell Line: An In Vitro Study

Polysaccharide extracts exhibit promise as potential anticancer agents. Among the fungi rich in polysaccharide content, G. applanatum stands out; however, its anticancer activity necessitates further investigation. This study aims to explore the impact of G. applanatum crude polysaccharide (GACP) extract by assessing its effects on cell viability, levels of proinflammatory cytokines such as TNF-α, IFN-γ, IL-2, and IL-12, and levels of proapoptotic markers including caspase-3 and caspase-9, as well as the percentages of necrosis and apoptosis in the HeLa cell line. Employing the HeLa cell line as a research model, four groups were studied: KN (media and DMSO), K+ (doxorubicin 10 μg/mL), P1 (G. applanatum extract 200 μg/mL), and P2 (G. applanatum extract 400 μg/mL). The G. applanatum extract was obtained via boiling distilled water. Anticancer activity was evaluated through the MTT test (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide) conducted over three treatment durations (24, 48, and 72 hours). Cytokine levels and caspase-3 and caspase-9 levels were assessed using the ELISA test. Cell apoptosis was determined using the Annexin V-PI biomarker and analyzed through flow cytometry. The MTT test exhibited optimal results at the 48-hour treatment mark. Cytokine level analysis revealed significant reductions in TNF-α, IFN-γ, IL-2, and IL-12 levels (p < 0.005). Concurrently, caspase-3 and caspase-9 levels exhibited substantial increases (p < 0.005). Flow cytometry highlighted the highest percentage of apoptosis in HeLa cells. In conclusion, G. applanatum's polysaccharide extract demonstrates potential as an anticancer and therapeutic agent for cancer treatment.

The Effect of Hypoxia on the Expression of CXC Chemokines and CXC Chemokine Receptors-A Review of Literature

Hypoxia is an integral component of the tumor microenvironment. Either as chronic or cycling hypoxia, it exerts a similar effect on cancer processes by activating hypoxia-inducible factor-1 (HIF-1) and nuclear factor (NF-κB), with cycling hypoxia showing a stronger proinflammatory influence. One of the systems affected by hypoxia is the CXC chemokine system. This paper reviews all available information on hypoxia-induced changes in the expression of all CXC chemokines (CXCL1, CXCL2, CXCL3, CXCL4, CXCL5, CXCL6, CXCL7, CXCL8 (IL-8), CXCL9, CXCL10, CXCL11, CXCL12 (SDF-1), CXCL13, CXCL14, CXCL15, CXCL16, CXCL17) as well as CXC chemokine receptors—CXCR1, CXCR2, CXCR3, CXCR4, CXCR5, CXCR6, CXCR7 and CXCR8. First, we present basic information on the effect of these chemoattractant cytokines on cancer processes. We then discuss the effect of hypoxia-induced changes on CXC chemokine expression on the angiogenesis, lymphangiogenesis and recruitment of various cells to the tumor niche, including myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), tumor-associated neutrophils (TANs), regulatory T cells (T_regs) and tumor-infiltrating lymphocytes (TILs). Finally, the review summarizes data on the use of drugs targeting the CXC chemokine system in cancer therapies.

Cancer cachexia has many symptoms but only one cause: anoxia

During nearly 100 years of research on cancer cachexia (CC), science has been reciting the same mantra: it is a multifactorial syndrome. The aim of this paper is to show that the symptoms are many, but they have a single cause: anoxia. CC is a complex and devastating condition that affects a high proportion of advanced cancer patients. Unfortunately, it cannot be reversed by traditional nutritional support and it generally reduces survival time. It is characterized by significant weight loss, mainly from fat deposits and skeletal muscles. The occurrence of cachexia in cancer patients is usually a late phenomenon. The conundrum is why do similar patients with similar tumors, develop cachexia and others do not? Even if cachexia is mainly a metabolic dysfunction, there are other issues involved such as the activation of inflammatory responses and crosstalk between different cell types.  The exact mechanism leading to a wasting syndrome is not known, however there are some factors that are surely involved, such as anorexia with lower calorie intake, increased glycolytic flux, gluconeogenesis, increased lipolysis and severe tumor hypoxia. Based on this incomplete knowledge we put together a scheme explaining the molecular mechanisms behind cancer cachexia, and surprisingly, there is one cause that explains all of its characteristics: anoxia.  With this different view of CC we propose a treatment based on the physiopathology that leads from anoxia to the symptoms of CC.  The fundamentals of this hypothesis are based on the idea that CC is the result of anoxia causing intracellular lactic acidosis. This is a dangerous situation for cell survival which can be solved by activating energy consuming gluconeogenesis. The process is conducted by the hypoxia inducible factor-1α. This hypothesis was built by putting together pieces of evidence produced by authors working on related topics.

Comparison of In Vitro Chlamydia muridarum Infection Under Aerobic and Anaerobic Conditions

Although Chlamydia infects host body regions that are hypoxic to anoxic, standard Chlamydiae culture conditions are in CO₂ enriched (5%) atmospheric oxygen (21%). Because of its success in causing disease in principally anaerobic body sites, e.g., vaginal tract, we hypothesize that Chlamydia has an anaerobic life cycle that plays a role in its maintenance in the host. Using a model system developed for the anaerobic culture of mammalian cells, we assessed the anoxic infectious cycle of C. muridarum in anaerobically cultured HeLa 229 cells. In the absence of oxygen, C. muridarum is capable of going through their life cycle, although its cycle is slowed (2 days post-infection anaerobic vs. 1 day aerobic). Interestingly, in addition to a slower rate of replication, there is a reduction in Chlamydia inclusion number and size as compared to aerobic controls. Anaerobic infected host cell physiology also changed with IL-6 and IL-8 production significantly lower (p ≤ 0.05) compared to aerobic infected host cells (day 4 post-infection). These findings demonstrate that Chlamydia are capable of replicating in the absence of oxygen.

The Pharmacological Effects of Spatholobi Caulis Tannin in Cervical Cancer and Its Precise Therapeutic Effect on Related circRNA

The chemical components of Spatholobi Caulis tannin (SCT) have a modest therapeutic effect in patients with cervical cancer. However, the active components and the mechanism of action of SCT in HeLa cervical cancer cells need to be further studied. In this paper, 3D microfluidic chip technology was applied to simulate the effects of tannins in the human body, and the appropriate dose and time of administration were calculated. The cell cycle and apoptosis experiments demonstrated that SCT inhibits proliferation and stimulated apoptosis in HeLa cells. The differentially expressed genes were screened using The Cancer Genome Atlas (TCGA) and the GEO databases to identify common differentially expressed genes. A bioinformatic analysis of relevant genes, analysis using the molecular docking technique, and survival analysis were used to predict the target genes of SCT. Circular RNAs (circRNAs) associated with the SCT target genes and the regulatory effects of SCT on these circRNAs were determined. These studies showed that SCT mediates related circRNAs in HeLa cells to inhibit proliferation and promote apoptosis in HeLa cells. Thus, SCT may be an effective strategy for treating cervical cancer.