Colorectal Neoplasia and the Colorectal Microbiome

Dysplasia, Probiotics, and Fusobacteria

Martin H. Floch

• Publisher: Academic Press
• Year: 2020
• Print ISBN:
  9780128196724
• eBook ISBN:
  9780128225615
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

Colorectal Neoplasia and the Microbiome: Dysplasia, Probiotics, and Fusobacteria provides foundational knowledge on the gut microbiome and evidence for an association with colorectal neoplasia. It covers the role of microbiota in causing adenomatous polyps and colorectal cancer as well as the modulatory effect of diet and probiotics. Chapters explain a foundational history of microbiology in the colon, the epidemiology of colon polyps and cancer, dysbiosis, the role of immunology and bacteria, and the diet. The book combines medical and scientific aspects to show mechanistic aspects between microbiota and hosts, clearly presenting the association between microbiota, colonic lesions and possible causal links. The book is essential reading for everyone working with human microbiota including basic scientists, physiologists of the intestine, experts in intestinal microbiota, gastroenterologists, oncologists and surgeon. - Provides foundational background on the complete history of microbiology in the colon - Offers thorough coverage of the connection between fusobacterium nucleatum, diet and bacteria on colon health - Presents the connection between immunology and bacteria in the colon

Chapter 1

History of bacteriology in the intestine

Martin Floch, Section of Gastroenterology and Nutrition, Yale, University School of Medicine, Norwalk Hospital, Norwalk, CT, United States

Abstract

The bacteriology of the intestine has a relatively short history. It started with the observations of smudges by Leuwenhoek in the 19th century and now into the recent magnitude of the vast realm of the microbiota. The microbiota consists of at least as many cells as in the body with hundreds of species. In the initial history, Pasteur identified disease with organisms, but the era of Koch identified details of infection. Koch’s work became the leadership philosophy as evidenced by his work in tuberculosis. This led to the era of realization that anaerobic organisms predominated in the intestine. We now appreciate that anaerobes predominate in humans.

Keywords

Microbiology; anaerobes; Pasteur; Koch; microbiota

The goal of this book is to understand the role of bacteria in the development of colorectal cancer. Therefore we will review the history of the recent knowledge available on the bacterial flora of the human intestine, and the following chapters will review the facts of human colorectal cancer, as well as the related bacteriology known about the disease.

Leeuwenhoek and Koch

The initial description of bacteria must be given to a Dutch clothier Leeuwenhoek who recorded observations of life forms using a makeshift microscope in the 17th century [1]. This was indeed very controversial. The next landmark in the history of the science of bacteriology is attributed to Robert Koch [2]. He was born in Germany on December 11, 1843, and his first papers were published in 1876 in English. When we look at the understanding of bacterial relationship to humans, his teaching and work were pivotal. Louis Pasteur had discovered that bacteria caused putrefaction, but Koch held to the theory that disease was caused by living transmissible entities [2]. After a tour in military service, Koch opened and maintained a clinical practice while visiting many research facilities. He was appointed district medical officer but maintained the clinical practice and began to investigate anthrax that was deadly to many humans and animals at that time.

He developed culture techniques, showed that the anthrax bacteria could develop spores, and that the disease was transmitted by inoculation. He had worked out the life cycle of the anthrax bacillus. This was so impressive to German scientists that Koch became a noted leader, and he took his place in history.

His work on cholera and the list of pathogens discovered by his techniques [2] is impressive and crosses paths as the modern history of intestinal bacteria flora advances. Most literature on intestinal bacteria relates to infectious diseases and, hence, the recent papers relating to the pathogens discovered by Koch’s followers.

Interest in the microbiota was stimulated by the publication of the human microbiome project [3] so that scientists around the world [4–6] began to reach the bacteriologic literature.

Our modern knowledge of the flora began with the work of Dubos and Schaedler who showed that anaerobes, not aerobes, were the predominant organisms in the intestine outnumbering the aerobes by 1000 to 1 per colony-forming units. At that time, others in the field headed by Luckey of Missouri, Feldman of California, Moore and Holdeman of Blacksburg, Virginia and Gorbach, and Golden of Boston began to publish their findings [3–11]. In our laboratories at Yale in New Haven and Norwalk, we developed techniques to identify flora and relate it to clinical situations [12,13]. The understanding of the anaerobic flora then extrapolated.

Anaerobes

Cholera and pathogenic E. coli were known aerobes [1] but anaerobic pathophysiology was less understood. Organisms of the Clostridia were isolated, but those such as Fusobacteria or Akkermansia were not yet understood or frequently identified. The textbook definition of an anaerobe is “an organism that requires reduced oxygen for growth. This means that an anaerobe fails to grow on the surface of solid media in 10% CO₂ in air. In contrast, facultative organisms can grow in the presence or absence of air and microaerophilic bacteria can grow in 10% CO₂ air or under aerobic or anaerobic conditions. As opposed to the strict requirement for survival of anaerobic conditions of several anaerobic species inhabiting our bodily surfaces, anaerobes that commonly cause infections are generally aerotolerant and can survive for up to 72 hours in the presence of an oxygenated atmosphere although they will not grow.” [1].

Hundreds of anaerobic organisms have been identified in the intestinal flora. The most common ones are listed in Table 1.1.

Table 1.1

Anaerobes commonly found in human infections [1].

Gram-negative

Bacteroides spp.

Porphyromonas spp.

Prevotella spp.

Fusobacterium spp.

Gram-positive

Peptostreptococcus spp.

Clostridium spp.

Actinomyces 22 spp.

The bacteriologists’ works previously noted revealed that anaerobes were predominant in the normal human intestine and were found in numerous human diseases [1–12]. They were found in disorders with immunoglobulin deficiencies, they were stable in stable patients, and were affected by the amount of fiber-containing foods in the diet [14–17].

So, what does the history of bacteriology teach us about cancer?

In summary, we have gone in a few centuries from where we related the scourge of infectious diseases such as cholera to the great discoveries of Leeuwenhoek and Koch but now are trying to relate the scourge of cancers to bacteria. Is this possible? We published a large textbook [18] on the microbiota pathophysiology of human gastrointestinal disease and learned that the microbiota were clearly related to human immunologic and metabolic processes in a wide variety of human diseases and disorders, including the irritable bowel syndrome and functional gastrointestinal disorders, acute infectious diseases, allergic disease, obesity, inflammatory bowel disease, and many liver diseases including nonalcoholic fatty liver and hepato-encephalopathy [18]. In the past, It had been noted that colorectal cancer was related to bacteria [15,19], but most theories that were advanced were based on the metabolism and breakdown substances of bile acids, but Fusobacteria were only noted in one manuscript [19].

The following chapters discuss and report on the functional relationship of individual bacteria species such as Streptococcus, Bacteroides, and Fusobacteria to colorectal neoplasia.

References

1. Mandell GL, Bennett JE, Dolan R. Principles and practice of infectious diseases 6th ed. Philadelphia, PA: Elsevier; 2005.

2. Blevens SM, Bronze MS. Robert Koch and the ‘golden age’ of bacteriology. Int J Infect Dis. 2010;14:e744–e751.

3. Turnbaugh PJ, Ley RE, Hamady M, et al. The human microbiome project. Nature. 2007;449:804–810.

4. Aries V, Crowther JS, Draser BS, et al. Bacteria and the aetiology of cancer of the large bowel. Gut. 1969;10:334–335.

5. Moore WE, Moore LH. Intestinal floras of populations that have a high risk of colo...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• List of Contributors
• Preface
• Chapter 1. History of bacteriology in the intestine
• Chapter 2. Epidemiology of colorectal cancer
• Chapter 3. Streptococcus gallolyticus and its implication in colorectal cancer
• Chapter 4. Bacteroides fragilis
• Chapter 5. Colorectal cancer and the microbiome: dysplasia, probiotics, and Fusobacterium nucleatum
• Chapter 6. Fusobacteria: physiology, form, and function
• Chapter 7. Dysbiosis of the intestinal microbiota and colorectal cancer
• Chapter 8. Microbiota, mucosal immunity, and Colon cancer
• Chapter 9. Diet—microbiome interaction in colorectal cancer: a potentially discriminatory role for Fusobacterium nucleatum
• Chapter 10. Colorectal cancer screening
• Index