Incidence of Colorectal Cancer After Intestinal Infection Due to Clostridioides difficile.

Background: Clostridioides difficile (C. difficile or C. diff) is a toxin-producing bacteria that is notorious for causing life-threatening diarrhea. Recent literature has investigated various effects of Clostridioides difficile infection (CDI) in cancer patients, but research into the impact of CDI on the development of cancer and its effects on the microbiome is limited. CDI predominately affects the colon, which urges consideration into the sequalae of infection. This study investigated the correlation between CDI and the incidence of colorectal carcinoma (CRC). Methods: A retrospective study (2010 - 2020) was conducted using a Health Insurance Portability and Accountability Act (HIPAA) compliant national database. The International Classification of Disease ninth and 10th Codes (ICD-9, ICD-10), Current Procedural Terminology (CPT), and National Drug Codes were used to identify CRC diagnosis, CDI, and matching or control parameters. Patients were matched for age, sex, Charlson Comorbidity Index (CCI), region of residence, and CDI treatment. An additional, but separate, query was executed to include obese patients with and without CDI, who were similarly matched and assessed for CRC. Statistical analyses were implemented to assess significance and estimate odds ratios (ORs). Results: CDI was associated with a decreased incidence of CRC (OR = 0.59, 95% confidence interval (CI): 0.55 - 0.63), and the difference was statistically significant (P < 2.2 × 10-16). CDI treatment, including appropriate antibiotics and fecal microbiota transplant (FMT), was controlled for in both infected and noninfected populations. Patients with a prior CDI who received relevant treatment were compared to patients with no history of CDI and received analogous treatment. Both populations subsequently developed CRC. Results remained statistically significant (P < 2.2 × 10-16) with a relative risk (RR) of 0.57 (95% CI: 0.54 - 0.60). Obesity was explored as a controlled variable in relation to CRC development in patients with and without prior CDI. Obese patients without a history of CDI were found to have a decreased risk of developing CRC. Results were statistically significant (P < 4.3 × 10-13) with an OR of 0.70 (95% CI: 0.63 - 0.77). Conclusions: This study shows a statistically significant correlation between CDI and decreased incidence of CRC. Additionally, there is a statistically significant correlation between obese patients with CDI and an increased incidence of CRC. Further research is needed to explore the mechanism of this striking relationship and the implications of CDIs on the microbiome.

The Role of Crohn Disease on Breast Cancer Incidence: A Clinical Analysis.

Background: Crohn disease is a chronic inflammatory disease that can affect the entire gastrointestinal tract. The pathophysiology of this disease characteristically involves transmural inflammation, which predisposes patients to various gastrointestinal cancers such as colon cancer. Although the increased risk of gastrointestinal cancers in Crohn disease has been well established, the risk of extra-gastrointestinal cancers remains unknown. We sought to study the risk of breast cancer in patients with Crohn disease. Methods: The data for this retrospective study were compiled using the International Classification of Disease Ninth Revision (ICD-9) and ICD 10th Revision (ICD-10) codes from the national Health Insurance Portability and Accountability Act (HIPAA)-compliant PearlDiver database from 2010 to 2019. Patients were matched for age, sex, and Charlson Comorbidity Index (CCI). Statistical analyses were implemented to assess Chi-squared, logistic regression, and odds ratio. Results: The database query resulted in 70,027 patients in both the control and Crohn disease groups. The incidence of breast cancer was 4,087 in the control group compared to 654 in the Crohn disease group. The P value was < 2.2 × 10-16 and the odds ratio was 0.15 (95% confidence interval (CI)). Patients without Crohn disease had an increased prevalence of breast cancer throughout all age ranges compared to patients with Crohn disease. Additionally, patients without Crohn disease had higher rates of breast cancer throughout the four major regions of the United States. In terms of healthcare costs, patients with breast cancer and a history of Crohn disease paid $23.87 more per hospital visit compared to patients with breast cancer and no history of Crohn disease. Conclusions: The results of this study indicate a statistically significant correlation between Crohn disease and a reduced incidence of breast cancer. This finding is true across all age groups and across the United States. Further study is required to investigate a possible mechanism between the pathophysiology of Crohn disease ultimately leading to reduced tumorigenesis in the breast.

Improving Value in Colorectal Cancer Care: An Economic Analysis of Enhanced Recovery Protocols at a Community Hospital.

Background: Enhanced recovery protocols (ERPs) have been shown to improve the outcomes of gastrointestinal cancer care, leading to reduced morbidity of gastrointestinal treatment and reduced delays in systemic therapy. ERP implementation has also previously shown a reduction in length of stay (LOS) without changing the readmission rate; however, the economic cost associated with these measures has not yet been quantified. The aim of this study was to evaluate the economic costs of ERP implementation for colorectal cancer at a community hospital. Methods: The Diagnostic Related Group (DRG) codes were used to assess costs associated with the hospitalizations of cases in the ERP versus non-ERP groups. The American Hospital Association (AHA) Annual Survey from 1999 to 2015 was used to provide the expenses per day for inpatient hospitalization in the United States. Postoperative LOS, average healthcare costs, and postoperative complications between ERP-protocol and non-ERP protocol groups were analyzed using analysis of variance (ANOVA) and independent t-tests. Results: The AHA survey estimated that $2,265 was incurred per day for non-profit hospitals in Florida and $2,346 was incurred per day for the United States. For all DRG codes, the ERP-participating group was associated with a shorter LOS and reduced health care costs. LOS-associated cost was compared between ERP and non-ERP groups: for DRG 329, the total savings was $162,118.8 (n = 12 non-ERP versus n = 8 ERP, P = 4.39 × 10-18); for DRG 330, $314,552.64 (n = 36 non-ERP versus n = 24 ERP, P = 2.72 × 10-22); and for DRG 331, $89,302.73 (n = 11 non-ERP versus n = 23 for ERP, P = 4.19 × 10-20). Conclusions: The implementation of an ERP protocol for colorectal cancer was associated with significantly reduced costs in a community hospital.

Hemophilus influenzae Infection's Association With Decreased Risk of Breast Cancer.

Background: Hemophilus influenzae (H. influenzae) is a common cause of widespread bacterial infections and has been associated with the stabilization of the microbiome. The microbiome, through modulating systemic inflammation with possible upregulation of the NLRP3 inflammasome, may potentiate the development of breast cancer (BC). The purpose of this study was to therefore evaluate the correlation between previous H. influenzae infection and the incidence of BC. Methods: A large national database was used to collect International Classification of Disease Ninth and Tenth Codes to evaluate the incidence of BC between January 2010 and December 2019 in patients with and without H. influenzae history. A retrospective cohort study was performed where these groups of individuals were matched by age range, Charlson Comorbidity Index (CCI), and antibiotic treatment exposure. Significance and relative risk were obtained using standard statistical procedures. Results: A total of 13,599 patients were matched by age range and CCI in both the experimental and control groups. BC incidence was 259 (1.905%) in the H. influenzae group compared to 686 (5.044%) in the control group (P < 2.2 × 10-16; odds ratio (OR) = 0.604, 95% confidence interval (CI): 0.553 - 0.660). Matching by antibiotic treatment exposure resulted in two groups of 3,189 patients, in which BC incidence was 98 (3.073 %) in the H. influenzae group compared to 171 (5.362%) in the control group (P < 2.2 × 10-16; OR = 0.584, 95% CI: 0.515 - 0.661). Conclusion: The study shows a statistically significant correlation between H. influenzae and a reduced incidence of BC. These results warrant further research regarding H. influenzae's role in upregulating the NLRP3 inflammasome and its potential role in BC prevention and treatment.

The Role of Hemophilus influenzae Infection and Its Relationship With Colorectal Cancer.

Background: Hemophilus influenzae is a gram-negative coccobacillus. Non-typeable H. influenzae infection is a significant cause of disease that activates the inflammatory pathway involving the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome. A gain-of-function mutation in NLRP3 results in cryopyrin-associated periodic syndromes characterized by inflammatory conditions in the lungs, skin, joints, and eyes but not in the gut. This leads to homeostasis of the gut microbiota, which reduces inflammation and may have protective effect against colorectal cancer (CRC). This study aimed to evaluate the correlation between H. influenzae infection and the incidence of CRC. Methods: A retrospective study was conducted from 2010 to 2019 using a HIPAA-compliant national database. ICD-10, ICD-9, CPT, and National Drug Codes were used to identify patients with or without a history of H. influenzae infection. Standard statistical methods were used to analyze the outcomes. Results: The query was analyzed and matched, resulting in 13,610 patients in both groups. The incidence of CRC was 167 and 446 in the H. influenzae and control groups, respectively. The difference was statistically significant with P < 2.2 ×10-16 and an odds ratio of 0.41 (95% confidence interval: 0.36 - 0.47). Additionally, the groups were further evaluated and matched by treatment, which resulted in a statistically significant decrease in CRC incidence in the H. influenzae group. Conclusion: This study showed a statistically significant correlation between H. influenzae and the reduced incidence of CRC. This reduction in CRC in patients with a history of H. influenzae infection suggests a potential link to the NLRP3 inflammasome, which should be further studied.

The Association of Human Cytomegalovirus Infection and Colorectal Cancer: A Clinical Analysis.

Background: Human cytomegalovirus (HCMV) commonly infects humans and establishes lifelong infection. It causes disease and increased mortality rates in patients with immunosuppression. HCMV gene products are found to be present in multiple human malignancies and target cellular functions involved in tumor development; additionally, a tumor-cytoreductive role of CMV has also been observed. The purpose of this study was to evaluate the correlation between CMV infection and the incidence of colorectal cancer (CRC). Methods: The data were provided by a national database that is compliant with Health Insurance Portability and Accountability Act (HIPAA). Using International Classification of Disease (ICD)-10 and ICD-9 diagnostic codes, the data were filtered to evaluate patients infected with HCMV versus patients never infected with HCMV. Patient data from 2010 to 2019 were assessed. Access to the database was granted by Holy Cross Health, Fort Lauderdale for the purpose of academic research. Standard statistical methods were used. Results: Between January 2010 and December 2019, the query was analyzed and resulted in 14,235 patients after matching in the infected and control groups. The groups were matched by age range, sex, Charlson Comorbidity Index (CCI) score, and treatment. The incidence of CRC was 1.159% (165 patients) in the HCMV group and 2.845% (405 patients) in the control group. The difference after matching was statistically significant by a P-value < 2.2 × 10-16 with an odds ratio of 0.37 (95% confidence interval (CI) 0.32 - 0.42). Conclusions: The study shows a statistically significant correlation between CMV infection and a reduced incidence of CRC. Further evaluation is recommended to assess the potential of CMV in reducing CRC incidence.

Improving Gastrointestinal Cancer Care by Enhanced Recovery Protocol Implementation.

Background: Enhanced recovery protocols (ERPs) have become the standard of care for patients undergoing elective small bowel surgeries but have not yet been adequately studied in community hospitals. In this study, a multidisciplinary ERP was developed and implemented at a community hospital to include minimal anesthesia, early ambulation and enteral alimentation, and multimodal analgesia. The aim of this study was to determine the effects of the ERP on postoperative length of stay (LOS), readmission (RA) rates following bowel surgery, and postoperative outcomes. Methods: The study design was a retrospective review of patients undergoing major bowel resection at Holy Cross Hospital (HCH) from January 1, 2017 to December 31, 2017. Patient charts for diagnostic-related group (DRG) 329, 330, and 331 were retrospectively reviewed at HCH in 2017 to compare outcomes in ERP versus non-ERP cases. The Medicare claims database (CMS) was also retrospectively reviewed to compare HCH data to the national average LOS and RA for the same DRG codes. Mean values for LOS and RA were statistically compared to determine significant differences between ERP versus non-ERP patients at HCH and national CMS data versus HCH patients. Results: LOS was analyzed for each DRG at HCH. At HCH, for DRG 329, the mean LOS for non-ERP was 13.0833 days (n = 12) versus 3.375 days (n = 8) (P ≤ 0.001) for ERP. For DRG 330, the mean LOS for non-ERP was 10.861 days (n = 36) versus 4.583 days (n = 24) (P ≤ 0.001) for ERP. For DRG 331, the mean LOS for non-ERP was 7.272 days (n = 11) versus 3.348 days (n = 23) (P = 0.004) for ERP. LOS was also compared to national CMS data. The LOS at HCH for DRG 329 improved from the 10th to 90th percentile (n = 238,907); DRG 330 improved from the 10th to the 72nd percentile (n = 285,423); DRG 331 improved from 10th to 54th percentile (n = 126,941) (P < 0.001). The RA at HCH in ERP and non-ERP cases was 3% at 30 and 90 days. CMS RA for DRG 329 was 25.1% at 90 days and 9.9% at 30 days; DRG 330 RA was 18.3% at 90 days and 6.6% at 30 days; DRG 331 RA was 11% at 90 days and 3.9% at 30 days. Conclusion: Implementation of ERP following bowel surgery at HCH significantly improved outcomes, in comparison to non-ERP cases, national CMS data, and Humana data. Further research on ERP for other fields and its impact on outcomes in other community settings is recommended.

Esophageal Perforation in a 76-Year-Old Man After C5-C7 Anterior Discectomy and Anterior Plate Fusion.

Anterior cervical discectomy and fusion (ACDF) is indicated for the treatment of various cervical pathologies, including myelopathy, cervical disc degeneration, and radiculopathy. Esophageal perforation is a rare postsurgical complication of ACDF, although it poses serious and potentially fatal outcomes. Esophageal perforation has been described as the most fatal complication of the gastrointestinal tract as delayed diagnosis can lead to sepsis and death. Diagnosis of this complication is often difficult because it can be masked by various symptoms such as recurrent aspiration pneumonia, fever, dysphagia, and neck pain. While this complication usually occurs within the first 24 h post-surgery, it can also develop later and persist chronically in rare cases. Awareness and early recognition of this complication may improve outcomes and reduce mortality and morbidity. A 76-year-old man underwent C5-C7 ACDF in October 2017. A thorough review of the patient's postoperative condition included computed tomography (CT) and esophagogram, which were negative for signs of acute complications. The postoperative recovery was uneventful until several months post-procedure when he began to develop vague dysphagia and weight loss of unknown etiology. A CT scan was obtained 6 months postoperatively and was negative for perforation. He then underwent a battery of inconclusive procedures and scans at multiple institutions. After several months of persistent dysphagia and weight loss without a diagnosis, the patient presented to our network for further workup and treatment recommendations. Upper endoscopy was performed and showed fistulization between the esophagus and the metal hardware in the cervical spine. Esophagram demonstrated no obstruction but decreased peristalsis of the lower esophagus and lateral rightward deviation of the left upper cervical esophagus with minimal mucosal irregularities. These findings were secondary to mass effect of the cervical plate. The patient was successfully treated with a surgical approach using esophagogastroduodenoscopy (EGD) guided repair in layers and a sternocleidomastoid muscle flap. This report demonstrates a rare case of delayed esophageal perforation after ACDF and successful treatment of the perforation by surgical repair using the dual technique.

Incidence of Breast Cancer and Enterococcus Infection: A Retrospective Analysis.

Background: Enterococci role in the microbiome remains controversial, and researches regarding enterococcal infection (EI) and its sequelae are limited. The gut microbiome has shown to play an important role in immunology and cancer. Recent data have suggested a relationship between the gut microbiome and breast cancer (BC). Methods: Patients in a Health Insurance Portability and Accountability Act (HIPAA) compliant national database (2010 - 2020) were used for this retrospective study. International Classification of Disease (ICD) Ninth and Tenth Codes, Current Procedural Terminology (CPT), and National Drug Codes were used to identify BC diagnosis and EI. Patients were matched for age, sex, Charlson comorbidity index (CCI), antibiotic treatment, obesity, and region of residence. Statistical analyses were implemented to assess significance and estimate odds ratio (OR). Results: EI was associated with a decreased incidence of BC (OR = 0.60, 95% confidence interval (CI): 0.57 - 0.63) and the difference was statistically significant (P < 2.2 × 10-16). Treatment for EI was controlled for in both EI and noninfected populations. Patients with a prior EI and treated with antibiotics were compared to patients with no history of EI and received antibiotics. Both populations subsequently developed BC. Results remained statistically significant (P < 2.2 × 10-16) with an OR of 0.57 (95% CI: 0.54 - 0.60). In addition to standard matching protocol, obesity was controlled for in both groups by exclusively containing obese patients, but one group with prior EI and the other without. In obese patients, a lower incidence of BC was shown in the infected group compared to the noninfected group. Results were statistically significant (P < 2.2 × 10-16) with an OR of 0.56 (95% CI: 0.53 - 0.58). Age of BC diagnosis with and without a prior EI was analyzed and demonstrated increased BC incidence with increasing age in both groups, but less in the EI group. Incidence of BC based on region was analyzed, which showed lower BC incidence across all regions in the EI group. Conclusion: This study shows a statistically significant correlation between EI and decreased incidence of BC. Further exploration is needed to identify and understand not only the role of enterococcus in the microbiome, but also the protective mechanism(s) and impact of EI on BC development.

The Association Between Aspirin and Basal Cell Carcinoma: A Clinical and Financial Analysis.

Background: Nonmelanoma skin cancer (NMSC) is the most common malignancy. Basal cell carcinoma (BCC) comprises about 80% of all NMSCs and its incidence continues to rise. Although BCC rarely leads to metastases or increased mortality, its effects on healthcare costs and quality of life are substantial. Aspirin may prevent the development of basal cell carcinoma (BCC) by the inhibition of cyclooxygenase (COX) enzymes, which are associated with carcinogenesis and inflammation. This study therefore examined the effect of aspirin on the risk of BCC, its clinical outcomes, and its treatment costs. Methods: A retrospective study (2010 - 2018) was conducted using the Humana Health Insurance Database. International Classification of Disease ninth and 10th codes and National Drug Codes were used to identify BCC diagnoses and aspirin prescriptions. Patients were matched for age, sex, Charlson Comorbidity Score (CCI), and region of residence. Chi-squared, logistic regression, and odds ratio (OR) analyses were utilized to test for significance and to estimate relative risk. Results: Aspirin use was associated with a decreased incidence of BCC in unmatched (OR = 0.658, 95% confidence interval (CI) 0.526 - 0.820) and matched (OR = 0.54, 95% CI 0.47 - 0.61) analyses. Aspirin was also associated with a decreased BCC risk when stratified by hypertension (P = 3.888 × 10-5), chronic obstructive pulmonary disease (COPD) (P = 0.014), diabetes (P = 0.049) and tobacco use (P = 0.017). Aspirin use was not associated with risk of BCC when stratified by obesity (P = 0.408). The average paid per patient for BCC treatment was significantly higher for patients in the aspirin use group than in the aspirin nonuse group (P = 0.0087). Conclusions: While the high incidence and cost of treatment of BCC are demanding both clinically and financially, the low cost of aspirin and its widespread use may have vital implications for its preventative role in this disease. This study concluded that aspirin use was associated with a significantly decreased risk of BCC.

Urine as a Source of Liquid Biopsy for Cancer.

Tissue biopsy is the gold standard for diagnosis and morphological and immunohistochemical analyses to characterize cancer. However, tissue biopsy usually requires an invasive procedure, and it can be challenging depending on the condition of the patient and the location of the tumor. Even liquid biopsy analysis of body fluids such as blood, saliva, gastric juice, sweat, tears and cerebrospinal fluid may require invasive procedures to obtain samples. Liquid biopsy can be applied to circulating tumor cells (CTCs) or nucleic acids (NAs) in blood. Recently, urine has gained popularity due to its less invasive sampling, ability to easily repeat samples, and ability to follow tumor evolution in real-time, making it a powerful tool for diagnosis and treatment monitoring in cancer patients. With the development and advancements in extraction methods of urinary substances, urinary NAs have been found to be closely related to carcinogenesis, metastasis, and therapeutic response, not only in urological cancers but also in non-urological cancers. This review mainly highlights the components of urine liquid biopsy and their utility and limitations in oncology, especially in non-urological cancers.

Transcriptomic and functional pathway features were associated with survival after pathological complete response to neoadjuvant chemotherapy in breast cancer.

Pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) has been proposed as a surrogate endpoint for the prediction of long-term survival in breast cancer (BC); however, an increased pCR rate has not clearly correlated with improved survival. We hypothesized that some transcriptomic and functional pathway features correlate with survival after pCR in BC. We utilized 2 published NAC cohorts, 105 women with gene expression data before, "Baseline", and that changed during NAC, "Delta", and TCGA database with 1068 BC patients to investigate the relationship between the efficacy of NAC and survival utilizing differentially expressed-mRNAs, construction and analysis of the mRNA-hub gene network, and functional pathway analysis. In mRNA expression profiling, S100A8 was a gene involved in survival after pCR in Baseline and NDP was a gene involved in recurrence after pCR in Delta. In functional pathway analysis, we found multiple pathways involved in survival after pCR. In mRNA-hub gene analysis, HSP90AA1, EEF1A1, APP, and HSPA4 were related to recurrence in BC patients with pCR due to NAC. TP53, EGFR, CTNNB1, ERBB2, and HSPB1 may play a significant role in survival for patients with pCR. Interestingly, high HSP90AA1, HSPA4, S100A8, and TP53, and low EEF1A1, EGFR, and CTNNB1 expressing tumors have significantly worse overall survival in TCGA BC cohort. We demonstrated the genes and functional pathway features associated with pCR and survival utilizing the bioinformatics approach to public BC cohorts. Some genes involved in recurrence after pCR due to NAC also served as prognostic factors in primary BC.

Sphingosine Kinase 1 is Associated With Immune Cell-Related Gene Expressions in Human Breast Cancer.

BACKGROUND: Although previous experiments have implicated sphingosine-1-phosphate (S1P) as a links between immune reactions and cancer progression, the exact mechanism of this interaction has not comprehensively studied in clinical human samples. This study sought to evaluate the S1P regulation by sphingosine kinase 1 (SPHK1), an S1P-producing enzyme, in the immunity/immuno-reactivity of clinical human breast cancer surgical specimens. METHODS: S1P levels were examined in tumor, peritumoral, and normal human breast samples using mass spectrometry. Genomics Data Commons data portal of The Cancer Genome Atlas cohort was used to assess the expression of S1P-related and immune-related genes. RESULTS: S1P levels were significantly higher in tumor samples compared to peritumoral (P < 0.05) or normal human breast samples (P < 0.001). SPHK1 gene expression was elevated in tumoral samples compared to normal breast samples (P < 0.01). Furthermore, the elevated expression of SPHK1 in breast cancer tissue was associated with an increased expression of the different kinds of immune-related genes, such as CD68, CD163, CD4, and FOXP3 (forkhead box P3), in HER2-negative breast cancer. Network analysis showed the central role of SPHK1 in the interaction of S1P signaling and expression of immune cell-related proteins. CONCLUSIONS: We demonstrated that S1P is mainly produced by tumor tissue, rather than peritumoral tissue, in breast cancer patients. Our data revealed the involvement of S1P signaling in the regulation of immune-related genes, suggesting the links between S1P and complicated immune-cancer interactions in breast cancer patients.

The E2F Pathway Score as a Predictive Biomarker of Response to Neoadjuvant Therapy in ER+/HER2- Breast Cancer.

E2F transcription factors play critical roles in the cell cycle. Therefore, their activity is expected to reflect tumor aggressiveness and responsiveness to therapy. We scored 3905 tumors of nine breast cancer cohorts for this activity based on their gene expression for the Hallmark E2F targets gene set. As expected, tumors with a high score had an increased expression of cell proliferation-related genes. A high score was significantly associated with shorter patient survival, greater MKI67 expression, histological grade, stage, and genomic aberrations. Furthermore, metastatic tumors had higher E2F scores than the primary tumors from which they arose. Although tumors with a high score had greater infiltration by both pro- and anti-cancerous immune cells, they had an increased expression of immune checkpoint genes. Estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative cancer with a high E2F score achieved a significantly higher pathological complete response (pCR) rate to neoadjuvant chemotherapy. The E2F score was significantly associated with the expression of cyclin-dependent kinase (CDK)-related genes and strongly correlated with sensitivity to CDK inhibition in cell lines. In conclusion, the E2F score is a marker of breast cancer aggressiveness and predicts the responsiveness of ER-positive/HER2-negative patients to neoadjuvant chemotherapy and possibly to CDK and immune checkpoint inhibitors.

Clinical relevance of tumor microenvironment: immune cells, vessels, and mouse models.

The tumor microenvironment (TME) plays a crucial role in tumor progression, therapeutic response, and patient outcomes. TME includes immune cells, blood and lymphatic vessels, and so on. There are anti-cancer and pro-cancer immune cells. In general, infiltration of anti-cancer immune cells, such as cytotoxic T cells (CTLs), is associated with a favorable patient prognosis. In contrast, infiltration of pro-cancer immune cells, such as regulatory T cells (Tregs), tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs), is associated with a worse prognosis. However, some immune cells, which play an ambivalent role in cancer immunity, have demonstrated contradictory impacts on patient prognosis. Blood and lymphatic vessels play crucial roles in TME not only as delivery and draining systems of fluid and molecules, but also allowing cancer cells access to systematic circulation to metastasize. Angiogenesis promotes cancer aggressiveness and is associated with a worse prognosis. Its targeted therapy shows a benefit in some cancers, however, because the target can vary by caner type, a benefit of anti-angiogenesis therapy is limited in the current standard of care. Lymphangiogenesis plays a role in lymph node metastasis, thus, it is associated with a poor prognosis in some cancers. To study TME, the mouse model is one of the most commonly used tools. The choice of appropriate mouse model depends on the hypothesis being tested and the scientific question being asked. Here, we review recent studies that investigated the clinical relevance of TME components and introduce mouse models to study TME.

Fibroblasts as a Biological Marker for Curative Resection in Pancreatic Ductal Adenocarcinoma.

Achievement of microscopic tumor clearance (R0) after pancreatic ductal adenocarcinoma (PDAC) surgery is determined by cancer biology rather than operative technique. Fibroblasts are known to play pro-cancer roles; however, a small subset was recently found to play anti-cancer roles. Therefore, we hypothesized that intratumor fibroblasts contribute to curative resection and a better survival of PDAC. Utilizing a large, publicly available PDAC cohort, we found that fibroblast composition was associated with R0 curative resection. A high amount of fibroblasts in PDACs was significantly associated with a higher amount of mature vessels, but not with blood angiogenesis. A high amount of fibroblasts was also associated with a higher infiltration of anti-cancer immune cells, such as CD8+ T-cells and dendritic cells, together with higher inflammatory signaling, including IL2/STAT5 and IL6/JAK/STAT3 signaling. Further, the fibroblast composition was inversely associated with cancer cell composition in the bulk tumor, along with an inverse association with proliferative characteristics, such as MYC signaling and glycolysis. The patients with high-fibroblast PDACs showed an improved prognosis. In conclusion, we found that PDACs with high fibroblasts were associated with a higher R0 resection rate, resulting in a better prognosis. These findings may be due to less aggressive biology with a higher vascularity and anti-cancer immunity, and a low cancer cell component.

A Novel 4-Gene Score to Predict Survival, Distant Metastasis and Response to Neoadjuvant Therapy in Breast Cancer.

We generated a 4-gene score with genes upregulated in LM2-4, a metastatic variant of MDA-MB-231 (DOK 4, HCCS, PGF, and SHCBP1) that was strongly associated with disease-free survival (DFS) in TCGA cohort (hazard ratio [HR]>1.2, p < 0.02). The 4-gene score correlated with overall survival of TCGA (HR = 1 .44, p < 0 .001), which was validated with DFS and disease-specific survival of METABRIC cohort. The 4-gene score was able to predict worse survival or clinically aggressive tumors, such as high Nottingham pathological grade and advanced cancer staging. High score was associated with worse survival in the hormonal receptor (HR)-positive/Her2-negative subtype. High score enriched cell proliferation-related gene sets in GSEA. The score was high in primary tumors that originated, in and metastasized to, brain and lung, and it predicted worse progression-free survival for metastatic tumors. Good tumor response to neoadjuvant chemotherapy or hormonal therapy was accompanied by score reduction. High scores were also predictive of response to neoadjuvant chemotherapy for HR-positive/Her2-negative subtype. High score tumors had increased expression of T cell exhaustion marker genes, suggesting that the score may also be a biomarker for immunotherapy response. Our novel 4-gene score with both prognostic and predictive values may, therefore, be clinically useful particularly in HR-positive breast cancer.

G2M Cell Cycle Pathway Score as a Prognostic Biomarker of Metastasis in Estrogen Receptor (ER)-Positive Breast Cancer.

The vast majority of breast cancer death is a result of metastasis. Thus, accurate identification of patients who are likely to have metastasis is expected to improve survival. The G2M checkpoint plays a critical role in cell cycle. We hypothesized that breast cancer tumors with high activity of G2M pathway genes are more aggressive and likely to metastasize. To test this, we used the single-sample gene set variation analysis method to calculate the score for the Hallmark G2M checkpoint pathway using gene expression data of a total of 4626 samples from 12 human breast cancer cohorts. As expected, a high G2M pathway score correlated with enriched tumor expression of other cell proliferation-related gene sets. The score was significantly associated with clinical aggressive features of tumors and patient survival in estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Interestingly, a high G2M score of metastasis tumors was also significantly associated with worse survival. In primary as well as metastasis tumors with high scores, the infiltration of both pro- and anti-cancerous immune cells increased. Tumor G2M score was also associated with treatment response to systemic chemotherapy in ER-positive/HER2-negative cancer, and was predictive of response to cyclin-dependent kinase inhibition therapy.

Biologically Aggressive Phenotype and Anti-cancer Immunity Counterbalance in Breast Cancer with High Mutation Rate.

While cancer cells gain aggressiveness by mutations, abundant mutations release neoantigens, attracting anti-cancer immune cells. We hypothesized that in breast cancer (BC), where mutation is less common, tumors with high mutation rates demonstrate aggressive phenotypes and attract immune cells simultaneously. High mutation rates were defined as the top 10% of the mutation rate, utilizing TCGA and METABRIC transcriptomic data. Mutation rate did not impact survival although high mutation BCs were associated with aggressive clinical features, such as more frequent in ER-negative tumors (p < 0.01), in triple-negative subtype (p = 0.03), and increased MKI-67 mRNA expression (p < 0.01) in both cohorts. Tumors with high mutation rates were associated with APOBEC3B and homologous recombination deficiency, increasing neoantigen loads (all p < 0.01). Cell proliferation and immune activity pathways were enriched in BCs with high mutation rates. Furthermore, there were higher lymphocytes and M1 macrophage infiltration in high mutation BCs. Additionally, T-cell receptor diversity, cytolytic activity score (CYT), and T-cell exhaustion marker expression were significantly elevated in BCs with high mutation rates (all p < 0.01), indicating strong immunogenicity. In conclusion, enhanced immunity due to neoantigens can be one of possible forces to counterbalance aggressiveness of a high mutation rate, resulting in similar survival rates to low mutation BCs.

Novel Breast Cancer Brain Metastasis Patient-Derived Orthotopic Xenograft Model for Preclinical Studies.

The vast majority of mortality in breast cancer results from distant metastasis. Brain metastases occur in as many as 30% of patients with advanced breast cancer, and the 1-year survival rate of these patients is around 20%. Pre-clinical animal models that reliably reflect the biology of breast cancer brain metastasis are needed to develop and test new treatments for this deadly condition. The patient-derived xenograft (PDX) model maintains many features of a donor tumor, such as intra-tumor heterogeneity, and permits the testing of individualized treatments. However, the establishment of orthotopic PDXs of brain metastasis is procedurally difficult. We have developed a method for generating such PDXs with high tumor engraftment and growth rates. Here, we describe this method and identify variables that affect its outcomes. We also compare the brain-orthotopic PDXs with ectopic PDXs grown in mammary pads of mice, and show that the responsiveness of PDXs to chemotherapeutic reagents can be dramatically affected by the site that they are in.