The effect of intermittent hypoxia and fecal microbiota of OSAS on genes associated with colorectal cancer

Obstructive Sleep Apnea and Colorectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Obstructive sleep apnea (OSA), characterised by recurrent episodes of upper airway collapse, intermittent hypoxia (IH) and sleep fragmentation (SF), has been associated with carcinogenesis in pre-clinical models. The relationship between OSA and colorectal cancer (CRC) in clinical studies is controversial.

AIM

The objective of this meta-analysis was to assess the association between OSA and CRC.

METHODS

Two independent investigators searched studies indexed in CINAHL, MEDLINE, EMBASE, the Cochrane Database and clinicaltrials.gov that were randomised controlled trials (RCT) or observational studies evaluating the relationship between OSA and CRC. Studies were included if they had available odds ratios (OR) and relative risks (RR) or if hazard ratios (HR) with 95% confidence intervals (CI) were available and a reference group composed of participants who did not have OSA. OR and 95% CI were calculated using a random-effect, generic inverse variance method.

RESULTS

We included four observational studies out of 85 records, comprising a combined cohort of 5,651,662 identified patients in the data analysis. Three studies used polysomnography to identify OSA. The pooled OR of CRC in patients with OSA was 1.49 (95% CI, 0.75 to 2.97). The statistical heterogeneity was high with I2 of 95%.

CONCLUSIONS

Our study is unable to conclusively point towards OSA being a risk factor in the development of CRC, despite the plausible biological mechanisms for this. Further well-designed prospective RCT assessing the risk of CRC in patients with OSA and the impact of OSA treatments on the incidence and prognosis of CRC are needed.

Systemic Inflammatory Status of Patients with Obstructive Sleep Apnea Syndrome and the Predictive Value of Heparin-Binding Protein

Objective: To investigate the alteration of the systemic inflammatory status of patients with obstructive sleep apnea syndrome (OSAS) and the predictive value of heparin-binding protein (HBP) for OSAS. Methods: Patients with OSAS who were hospitalized in our hospital from 2020 January to 2022 December and diagnosed by polysomnography (PSG) (OSAS group, n = 79) were retrospectively studied and their relevant examination findings and demographic characteristics were recorded. Sex- and age-matched non-OSAS patients hospitalized at the same time were selected as the control group (control group, n = 28). Differences in peripheral blood neutrophil counts, lymphocyte counts, neutrophil-to-lymphocyte ratio (NLR), procalcitonin (PCT), and HBP were compared between the 2 groups. The predictive value of these markers for OSAS was analyzed using the receiver operating characteristic curve, and independent risk factors for OSAS were determined using logistic regression analysis. Peripheral blood was drawn from all patients in the fasting state of the morning. Results: The number of peripheral blood neutrophils, lymphocytes, and HBP was higher in the OSAS group than in the control group, and the differences were statistically significant (P all <.05), while the differences in NLR and PCT between the 2 groups were not statistically significant (P all >.05). Plasma HBP level had an area under the curve (AUC) of 0.79 (P < .0001) in determining OSAS, with a sensitivity of 80.49% and a specificity of 70.83% and the best cutoff value was >10.73 ng/ml. Combining body mass index (BMI), neutrophil, lymphocyte, and HBP improved the predictive value of OSAS with an AUC of 0.89 (P < .0001), a sensitivity of 80.49%, and a specificity of 87.50%. Logistic regression analysis showed that both BMI and HBP were independent risk factors for OSAS (PBMI < .001, PHBP < .01), while neutrophils and lymphocytes were not (P all >.05). Conclusions: This is the first study to objectively examine HBP in OSAS patients, and HBP is an independent risk factor that may serve as a diagnostic biomarker in OSAS. Patients with OSAS have an altered systemic inflammatory state and may be more prone to severe bacterial infections.

Testicular Cancer Incidence among Obstructive Sleep Apnea (OSA) Patients: South Korean National Health Insurance Data

Obstructive sleep apnea (OSA) has been linked to an increased risk of acquiring many types of cancer. No data on the prevalence of testicular cancer in OSA patients have been reported in the literature. The goal of the present investigation is to find out the impact of OSA on the incidence of testicular cancer based on the Korea National Health Insurance Service (KNHIS) dataset. A cohort of adult male patients newly registered with OSA in the KNHIS data from 2007 to 2014 who had no history of any previous cancer diagnosis was included. The main outcome measure was newly diagnosed testicular cancer in the National Medical Expenses Support Program. The control group was set at five times larger than the OSA group, and it was matched with age and sex. The cumulative incidence and hazard ratio (HR) for the development of testicular cancer were compared between the OSA and control groups. Further subgroup analysis was conducted in the three different age groups. In the study period, a total of 152,801 male adult patients newly diagnosed with OSA were included, whereas 764,005 individuals were recruited as the control group. The HR of OSA for developing testicular cancer was 1.58 (95% confidence interval [CI]: 0.92-2.60), showing no significant HR regardless of confounding adjustment. However, the subgroup analysis revealed a significantly increased HR to develop testicular cancer of 3.39 (95% CI: 1.08-10.06) in groups aged more than 65, whereas the age ranges of 20-40 and 40-64 showed no significance (1.19 (0.44-2.75) and 1.27 (0.50-2.80), respectively). OSA may not influence the incidence of testicular cancer in the general adult population. However, compared to younger males, males over 65 may be more susceptible to OSA when it comes to developing testicular cancer.

Potential Pathophysiological Pathways in the Complex Relationships between OSA and Cancer

Several epidemiological and clinical studies have suggested a relationship between obstructive sleep apnea (OSA) and a higher incidence or severity of cancer. This relationship appears to be dependent on a myriad of factors. These include non-modifiable factors, such as age and gender; and modifiable or preventable factors, such as specific comorbidities (especially obesity), the use of particular treatments, and, above all, the histological type or location of the cancer. Heterogeneity in the relationship between OSA and cancer is also related to the influences of intermittent hypoxemia (a hallmark feature of OSA), among others, on metabolism and the microenvironment of different types of tumoral cells. The hypoxia inducible transcription factor (HIF-1α), a molecule activated and expressed in situations of hypoxemia, seems to be key to enabling a variety of pathophysiological mechanisms that are becoming increasingly better recognized. These mechanisms appear to be operationally involved via alterations in different cellular functions (mainly involving the immune system) and molecular functions, and by inducing modifications in the microbiome. This, in turn, may individually or collectively increase the risk of cancer, which is then, further modulated by the genetic susceptibility of the individual. Here, we provide an updated and brief review of the different pathophysiological pathways that have been identified and could explain the relationship between OSA and cancer. We also identify future challenges that need to be overcome in this intriguing field of research.

Bugs as Drugs: Understanding the Linkage between Gut Microbiota and Cancer Treatment Microbiome in Cancer Therapy

BACKGROUND

The commensal microbiota is known to regulate host physiology. Dysbiosis or compromised Resilience in the microbial ecology is related to the impending risk of cancer. A potential link between cancer and microbiota is indicated by a lot of evidence.

OBJECTIVE

The current review explores in detail the various links leading to and /or facilitating oncogenesis, providing sound reasoning or a basis for its utilization as potential therapeutic targets. The present review emphasizes the existing knowledge of the microbiome in cancer and further elaborates on the factors like genetic modifications, effects of dietary components, and environmental agents that are considered to assess the direct and indirect effect of microbes in the process of oncogenesis and on the host's health. Strategies modulating the microbiome and novel biotherapeutics are also discussed. Pharmacomicrobiomics is one such niche accounting for the interplay between the microbiome, xenobiotic, and host responses is also looked upon.

METHODS

The literature search strategy for this review was conducted by following the methodology of the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). The method includes the collection of data from different search engines like PubMed, ScienceDirect, SciFinder etc. to get coverage of relevant literature for accumulating appropriate information regarding microbiome, cancer, and their linkages.

RESULTS

These considerations are made to expand the existing literature on the role of gut microbiota on the host's health, the interaction between host and microbiota, and the reciprocal relationship between the microbiome and modified neoplastic cells.

CONCLUSION

Potential therapeutic implications of cancer microbiomes that are yet unexplored and have rich therapeutic dividends improving human health are discussed in detail in this review.

Obstructive Sleep Apnea Worsens Progression-Free and Overall Survival in Human Metastatic Colorectal Carcinoma

Sleep disorders have emerged as highly prevalent conditions, and along with improved understanding of such disorders, increased attention has gained the evidence that perturbation in sleep architecture and continuity may initiate, exacerbate, or modulate the phenotypic expression of multiple diseases including cancer. Furthermore, obstructive sleep apnea (OSA) has recently been implicated in increased incidence and more adverse prognosis of cancer in humans. This study was designed to confirm the high prevalence of OSA in human malignancies and assess its prognostic relevance in metastatic colorectal carcinomas (mCRCs). A prospective cohort of 52 subjects, affected by solid histologically confirmed metastatic malignancies, was analyzed, and among them, 29 mCRCs were studied for the prognostic role of OSA. OSA was diagnosed in 34.6% (18/52) of patients with a statistically significant difference in apnea-hyponea index between OSA and non-OSA subgroups (14.2 ± 12.2 vs. 2.1 ± 1.5, p < 0.01). Consistently, OSA was diagnosed in 34.5% (10/29) of mCRCs with lower rates of first-line therapy disease control in OSA compared to non-OSA patients (60% in OSA vs. 94.7% in non-OSA, p=0.03). Of note, progression-free and overall survival rates were significantly shorter in OSA (respectively, 9 and 22 months) compared non-OSA (20 and 40 months) mCRC patients (HR = 2.63; 95% CI 0.88-7.84, p=0.01 for PFS; HR = 3.93; 95% CI 1.13-13.73, p < 0.001 for OS). Finally, the multivariate analysis showed that OSA is an independent prognostic factor for PFS (p=0.0076) and OS (p=0.0017) in this cohort. Altogether, these data suggest that OSA is a potential clinical marker predictor of poor prognosis in patients with mCRC.

Sleep Apnoea Adverse Effects on Cancer: True, False, or Too Many Confounders?

Obstructive sleep apnoea (OSA) is a prevalent disorder associated with increased cardiovascular, metabolic and neurocognitive morbidity. Recently, an increasing number of basic, clinical and epidemiological reports have suggested that OSA may also increase the risk of cancer, and adversely impact cancer progression and outcomes. This hypothesis is convincingly supported by biological evidence linking certain solid tumours and hypoxia, as well as by experimental studies involving cell and animal models testing the effects of intermittent hypoxia and sleep fragmentation that characterize OSA. However, the clinical and epidemiological studies do not conclusively confirm that OSA adversely affects cancer, even if they hold true for specific cancers such as melanoma. It is likely that the inconclusive studies reflect that they were not specifically designed to test the hypothesis or because of the heterogeneity of the relationship of OSA with different cancer types or even sub-types. This review critically focusses on the extant basic, clinical, and epidemiological evidence while formulating proposed directions on how the field may move forward.