Metagenomic studies using next-generation sequencing technologies have revealed rich human intestinal microbiome, which likely influence host immunity and health conditions including cancer. Evidence ...indicates a biological link between altered microbiome and cancers in the digestive system.
Escherichia coli
and
Bacteroides fragilis
have been found to be enriched in colorectal mucosal tissues from patients with familial adenomatous polyposis that is caused by germline
APC
mutations. In addition, recent studies have found enrichment of certain oral bacteria, viruses, and fungi in tumor tissue and fecal specimens from patients with gastrointestinal cancer. An integrative approach is required to elucidate the role of microorganisms in the pathogenic process of gastrointestinal cancers, which develop through the accumulation of somatic genetic and epigenetic alterations in neoplastic cells, influenced by host genetic variations, immunity, microbiome, and environmental exposures. The transdisciplinary field of molecular pathological epidemiology (MPE) offers research frameworks to link germline genetics and environmental factors (including diet, lifestyle, and pharmacological factors) to pathologic phenotypes. The integration of microbiology into the MPE model (microbiology–MPE) can contribute to better understanding of the interactive role of environment, tumor cells, immune cells, and microbiome in various diseases. We review major clinical and experimental studies on the microbiome, and describe emerging evidence from the microbiology–MPE research in gastrointestinal cancers. Together with basic experimental research, this new research paradigm can help us to develop new prevention and treatment strategies for gastrointestinal cancers through targeting of the microbiome.
Glucose transporter 1 (GLUT1) expression is a prognostic marker for esophageal squamous cell carcinoma (ESCC). Recent work on GLUT1 and development of specific inhibitors supports the feasibility of ...GLUT1 inhibition as a treatment for various cancers. The anti–proliferative effects of GLUT1‐specific small interfering RNA (siRNA) and a GLUT1 inhibitor were evaluated in ESCC cell lines. Expression of pro–proliferative and anti–proliferative signaling and effector molecules was examined by western blotting and quantitative RT‐PCR. GLUT1 expression in pretreatment clinical biopsy samples was measured by immunohistochemistry and correlated with various clinicopathological parameters and response to chemotherapy. The reduction in standardized uptake value (SUV) of 18F‐fluoro‐deoxyglucose was calculated using the formula: (pretreatment SUVmax – posttreatment SUVmax/pretreatment SUVmax) × 100. GLUT1‐specific siRNA expression in ESCC cells inhibited their proliferation, increased expression of p27kip, and decreased expression of cyclin‐dependent kinase 6, pyruvate kinase muscle isozyme M2, lactate dehydrogenase A and phospho‐ERK1/2. Suppression of GLUT1 by siRNA increased low‐dose cisplatin‐induced inhibition of proliferation of TE‐11 ESCC cells, which express high GLUT1 levels. Similarly, BAY‐876, a GLUT1 inhibitor, enhanced cisplatin‐mediated inhibition of ESCC cell proliferation. GLUT1 expression in pretreatment biopsy samples was associated with the response to chemotherapy as well as the pathological tumor stage and histological response grade after esophagectomy. Finally, GLUT1‐negative tumors showed a significantly larger reduction in SUVmax (61.2% ± 4.5%) compared with GLUT1‐positive tumors (46.2% ± 4.4%). GLUT1 expression may be a surrogate marker of response to chemotherapy, and inhibition of GLUT1 may be a potential novel therapy for ESCC patients.
Recent work on GLUT1 and development of specific inhibitors supports the feasibility of GLUT1 inhibition as a treatment for various cancers. This study demonstrated that downregulation of GLUT1 expression had a strong anti–proliferative effect in ESCC cells and also improved their sensitivity to cisplatin. GLUT1 expression may be a surrogate marker of response to chemotherapy, and inhibition of GLUT1 may be a potential novel therapy for ESCC patients.
Fusobacterium nucleatum has been detected in 8%‐13% of human colorectal cancer, and shown to inhibit immune responses against primary colorectal tumors in animal models. Thus, we hypothesized that ...the presence of F. nucleatum might be associated with reduced T cell density in colorectal cancer liver metastases (CRLM). We quantified F. nucleatum DNA in 181 CRLM specimens using quantitative PCR assay. The densities of CD8+ T cells, CD33+ cells (marker for myeloid‐derived suppressor cells MDSCs), and CD163+ cells (marker for tumor‐associated macrophages TAMs) in CRLM tissue were determined by immunohistochemical staining. Fusobacterium nucleatum was detected in eight (4.4%) of 181 CRLM specimens. Compared with F. nucleatum‐negative CRLM, F. nucleatum‐positive CRLM showed significantly lower density of CD8+ T cells (P = .033) and higher density of MDSCs (P = .001). The association of F. nucleatum with the density of TAMs was not statistically significant (P = .70). The presence of F. nucleatum is associated with a lower density of CD8+ T cells and a higher density of MDSCs in CRLM tissue. Upon validation, our findings could provide insights to develop strategies that involve targeting microbiota and immune cells for the prevention and treatment of CRLM.
Fusobacterium nucleatum was detected in eight (4.4%) of 181 colorectal cancer liver metastasis tissue. We found that the presence of F. nucleatum was associated with lower CD8+ T cell density and greater densities of both myeloid‐derived suppressor cells and tumor‐associated macrophages.
Background
With aging of the population, the number of colorectal cancer patients with impairment of activities of daily living (ADLs) has increased. The Barthel index is a validated tool for ...assessing functional levels of ADLs. In this retrospective study, we aimed to examine associations of Barthel index scores with recurrence and mortality after curative resection of colorectal cancer.
Methods
We retrospectively analyzed data of 815 consecutive patients who had undergone curative resection of stage I–III colorectal adenocarcinoma between January 2009 and December 2017. Preoperative functional levels of ADLs were assessed prospectively using the Barthel index (range, 0 to 100; higher scores indicate greater independence). Recurrence-free survival (RFS) and overall survival (OS) were compared according to Barthel index scores. The Cox proportional hazards model was used to calculate hazard ratios (HRs), controlling for potential confounders.
Results
Of the 815 patients, Barthel index scores were 40 or lower in 129 (16%), 41–85 in 110 (13%), and 86 or more in 576 (71%). In multivariable analyses adjusting for potential confounders including age and disease stage, scores of 85 or lower on the Barthel index were independently associated with shorter RFS (multivariable HR: 1.74, 95% confidence interval: 1.28–2.37,
P
<0.001) and OS (multivariable HR: 2.10, 95% confidence interval: 1.45–3.04,
P
<0.001).
Conclusions
Lower scores on the Barthel index are associated with shorter RFS and OS following resection of nonmetastatic colorectal cancer. Further studies are needed to establish treatment strategies for colorectal cancer patients with poor functional capacity.
Inflammatory and immune cells in the tumor microenvironment are reported to be associated with tumor progression in several cancers. In total, 225 patients who underwent initial and curative ...hepatectomy for hepatocellular carcinoma (HCC) from 2004 to 2013 were enrolled in this study. Tumor‐associated neutrophils (TANs), M2 macrophages (TAMs; tumor‐associated macrophages), CD8+ T cells, and regulatory T cells (Tregs) were evaluated by immunohistochemistry (IHC), and their relationships with patient clinicopathological characteristics and prognosis were evaluated. IHC was performed focusing on TANs first. We could not find a relationship between intratumoral and peritumoral TANs and clinicopathological features except for the fibrous capsule and infiltration of tumors into capsule. Next, TAMs, CD8+ cells and Tregs were evaluated by IHC. At the peritumoral area, TANs and TAMs (r = 0.36, p = 0.001) or Tregs (r = 0.16, p = 0.008) showed a positive correlation, whereas TANs and CD8+ cells showed a negative correlation (r = −0.16, p = 0.02). As for survival outcomes, at the peritumoral area, high TANs (p = 0.0398), low CD8+ cells (p = 0.0275), and high TAMs (p = 0.001) were significantly associated with worse overall survival (OS). In addition, high TANs (p = 0.010), and high TAMs (p = 0.00125) were significantly associated with worse disease‐free survival (DFS). Finally, we established a risk signature model by combining the expression patterns of these cells. The high‐risk signature group had significantly worse OS (p = 0.0277) and DFS (p = 0.0219) compared with those in the low‐risk signature group. Our risk signature based on immune cells at the peritumoral area of the HCC can predict patient prognosis of HCC after curative hepatectomy.
In this study, we showed that infiltration of inflammatory and immune cells at peri‐tumoral site of HCC showed a significant association with patients’ prognosis. We also made risk signature evaluated by the infiltration of immune cells at peri‐tumoral site of HCC, and it might to be a new prognostic marker of patients with HCC after curative hepatectomy.
Background
The number of frail patients with colorectal cancer (CRC) has increased. Despite evidence-based treatment guidelines, a large proportion of patients with resected CRC do not receive ...adjuvant chemotherapy in daily practice. This retrospective study aimed to examine the effect of adjuvant chemotherapy for CRC according to frailty.
Methods
We retrospectively analyzed data from 507 consecutive patients with curatively resected high-risk stage II or stage III CRC between 2009 and 2016. Frailty was assessed using the Clinical Frailty Scale (CFS): 1 (very fit) to 9 (terminally ill), and frailty was defined as CFS ≥ 4. Recurrence-free survival (RFS) and overall survival (OS) were compared between surgery alone and adjuvant chemotherapy in frail and non-frail patients. A cox proportional hazards model was used to calculate hazard ratios (HRs), controlling for potential confounders.
Results
Of the 507 patients, 194 (38%) were frail. There were no significant interactions between frailty and adjuvant chemotherapy regarding RFS (
P
interaction
= 0.59) and OS (
P
interaction
= 0.81). In multivariable analyses, associations of adjuvant chemotherapy with longer RFS and OS in frail patients (RFS, HR: 0.33, 95% CI 0.15–0.63; OS, HR: 0.23, 95% CI 0.08–0.54) were comparable to non-frail patients (RFS, HR: 0.36, 95% CI 0.22–0.58; OS, HR: 0.34, 95% CI 0.15–0.69). Frail patients receiving adjuvant chemotherapy were younger and had better nutritional status than those undergoing surgery alone (all
P
< 0.005).
Conclusion
Selected frail patients with CRC may experience a similar survival benefit from adjuvant chemotherapy as non-frail patients. Clinical trials are needed to establish adjuvant chemotherapy for CRC in frail patients.
Abstract The human intestinal microbiome encompasses at least 100 trillion microorganisms that can influence host immunity and disease conditions, including cancer. Hepatobiliary and pancreatic ...cancers have been associated with poor prognosis owing to their high level of tumor invasiveness, distant metastasis, and resistance to conventional treatment options, such as chemotherapy. Accumulating evidence from animal models suggests that specific microbes and microbial dysbiosis can potentiate hepatobiliary-pancreatic tumor development by damaging DNA, activating oncogenic signaling pathways, and producing tumor-promoting metabolites. Emerging evidence suggests that the gut microbiota may influence not only the efficacy of cancer chemotherapies and novel targeted immunotherapies such as anti-CTLA4 and anti-CD274 therapies but also the occurrence of postoperative complications after hepatobiliary and pancreatic surgery, which have been associated with tumor recurrence and worse patient survival in hepatobiliary-pancreatic cancers. Hence, a better understanding of roles of the gut microbiota in the development and progression of hepatobiliary-pancreatic tumors may open opportunities to develop new prevention and treatment strategies for patients with hepatobiliary-pancreatic cancer through manipulating the gut microbiota by diet, lifestyle, antibiotics, and pro- and prebiotics.
Large-scale genomic characterization of tumors from prospective cohort studies may yield new insights into cancer pathogenesis. We performed whole-exome sequencing of 619 incident colorectal cancers ...(CRCs) and integrated the results with tumor immunity, pathology, and survival data. We identified recurrently mutated genes in CRC, such as BCL9L, RBM10, CTCF, and KLF5, that were not previously appreciated in this disease. Furthermore, we investigated the genomic correlates of immune-cell infiltration and found that higher neoantigen load was positively associated with overall lymphocytic infiltration, tumor-infiltrating lymphocytes (TILs), memory T cells, and CRC-specific survival. The association with TILs was evident even within microsatellite-stable tumors. We also found positive selection of mutations in HLA genes and other components of the antigen-processing machinery in TIL-rich tumors. These results may inform immunotherapeutic approaches in CRC. More generally, this study demonstrates a framework for future integrative molecular epidemiology research in colorectal and other malignancies.
Display omitted
•Whole-exome sequencing of 619 colorectal cancers with clinicopathologic annotations•Discovery of significantly mutated genes in colorectal cancer•Neoantigen load correlation with infiltrating lymphocytes and memory T cells•Positive selection for HLA mutations in immune-cell-infiltrated tumors
Through whole-exome sequencing of annotated colorectal tumors, Giannakis et al. identify additional colorectal cancer driver genes and correlate high neoantigen load with increased lymphocytic infiltration and improved survival. They also find positive selection for HLA mutations in immune-cell-infiltrated tumors. These results may inform immunotherapeutic approaches in colorectal cancer.
Background
With population aging, the number of frail patients with pancreatic cancer has increased. The Clinical Frailty Scale (CFS) is a simple and validated tool to assess frailty, and higher ...scores predict worse clinical outcomes after cardiovascular surgery. In this retrospective study, we aimed to examine the association of preoperative frailty with prognosis after resection for pancreatic cancer.
Methods
We retrospectively analyzed data from 142 consecutive patients undergoing resection for pancreatic cancer between April 2010 and December 2018. We used the CFS: 1 (very fit) to 9 (terminally ill) to assess frailty and examined associations of the CFS scores with recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS). Multivariable Cox proportional hazards models were used to calculate hazard ratios (HRs), controlling for potential confounders.
Results
Of the 142 patients, 113 (80%) had CFS scores of ≤ 3, 13 (9.2%) scores of 4, and 16 (11%) scores of ≥ 5. Scores of ≥ 5 on the CFS were associated with worse CSS (univariable HR: 2.62, 95% confidence interval CI: 1.19–5.18,
P
= 0.019; multivariable HR: 2.49, 95% CI 1.05–5.34,
P
= 0.039) and OS (univariable HR: 2.42, 95% CI 1.19–4.46,
P
= 0.016; multivariable HR: 2.25, 95% CI 1.05–4.43,
P
= 0.038). The association between CFS scores and RFS was not significant in multivariable analysis (univariable HR: 2.11, 95% CI 1.08–3.79,
P
= 0.030; multivariable HR: 1.47, 95% CI 0.71–2.83,
P
= 0.29).
Conclusion
Higher scores on the CFS are associated with worse CSS and OS after resection for pancreatic cancer. Preoperative measurement of frailty may improve risk assessment among patients with pancreatic cancer.
Purpose Blockade of the programmed cell death 1 (PDCD1, PD-1) immune checkpoint pathway can improve clinical outcomes in various malignancies. Evidence suggests that aspirin (a widely used ...nonsteroidal anti-inflammatory drug) not only prolongs colorectal cancer survival, but can also activate T cell-mediated antitumor immunity and synergize with immunotherapy through inhibition of prostaglandin E2 production. We hypothesized that the survival benefit associated with aspirin might be stronger in colorectal carcinoma with a lower CD274 (PDCD1 ligand 1, PD-L1) expression level that resulted in lower signaling of the immune checkpoint pathway. Patients and Methods Using data from 617 patients with rectal and colon cancer in the Nurses' Health Study and the Health Professionals Follow-Up Study, we examined the association of postdiagnosis aspirin use with patient survival in strata of tumor CD274 expression status measured by immunohistochemistry. We used multivariable Cox proportional hazards regression models to control for potential confounders, including disease stage, microsatellite instability status, CpG island methylator phenotype, long interspersed nucleotide element-1 methylation, cyclooxygenase-2 (PTGS2), and CDX2 expression, and KRAS, BRAF, and PIK3CA mutations. Results The association of postdiagnosis aspirin use with colorectal cancer-specific survival differed by CD274 expression status ( P
< .001); compared with aspirin nonusers; multivariable-adjusted hazard ratios for regular aspirin users were 0.16 (95% CI, 0.06 to 0.41) in patients with low CD274 and 1.01 (95% CI, 0.61 to 1.67) in patients with high CD274. This differential association seemed consistent in patients with microsatellite-stable or PIK3CA wild-type disease and in strata of PTGS2 expression, CDX2 expression, tumor-infiltrating lymphocytes, or prediagnosis aspirin use status. Conclusion The association of aspirin use with colorectal cancer survival is stronger in patients with CD274-low tumors than CD274-high tumors. Our findings suggest a differential antitumor effect of aspirin according to immune checkpoint status.
PDF
