Different matrix micro-environments in colon cancer and diverticular disease

Evaluation of molecular and genetic predisposing parameters at diverticular disease of the colon

BACKGROUND

Diverticular disease (DD) refers to the presence of diverticula throughout the gastrointestinal (GI) tract, mainly along colon. DD might evolve into diverticulitis that is accompanied by severe clinical presentation, which includes abscess formation, perforation, stricture, obstruction and/or fistula.

AIM

The aim of the present review is to summarize the role of molecular and genetic factors in DD development, as well as their possible contribution towards new prognostic indicators, diagnostic algorithms and new therapeutic approaches.

METHODS AND RESULTS

Except from common predisposing parameters, several genetic mutations, immune factors, neurotransmitters, hormones and protein dysfunctions have been associated to the early onset of DD symptoms, pathogenesis and prognosis of the disease. Specific structural changes in the colonic wall, altered matrix composition and compromised motility have been verified as possible pathogenic factors for the development of DD. Dysregulation in peristaltic activity and reduced ability of the longitudinal muscle to relax following contraction has been also associated with DD evolution. In addition, it has been suspected that genetic defects combined with alterations in intestinal microbiota might play an important role in diverticulitis presentation.

Paradigm shift: the Copernican revolution in diverticular disease

Diverticular disease (DD) is an umbrella definition that includes different clinical conditions ranging from diverticulosis to severe and potentially life-threatening complications. In the last decade, new concepts regarding pathogenetic alterations have been developed, while the diagnostic, clinical and therapeutic approaches to the management of DD patients have changed. The protective role of dietary factors (i.e., fiber) has been questioned, whilst some drugs widely used in clinical practice have been found to have a deleterious effect. The use of antibiotics in all patients with acute uncomplicated diverticulitis was reconsidered, as well as the need for a surgical approach in these patients. Conflicting recommendations in different guidelines were proposed for the treatment of symptomatic uncomplicated DD. An endoscopic classification of DD was introduced, and a "curative" endoscopic approach has been pioneered. Based on these observations, which together amount to a kind of "Copernican revolution" in the management of DD patients, we performed a comprehensive and critical reappraisal of the proposed modifications, aiming to discriminate between certainties and doubts on this issue.

Hernia and Cancer: The Points Where the Roads Intersect

Introduction: This review aimed to present common points, intersections, and potential interactions or mutual effects for hernia and cancer. Besides direct relationships, indirect connections, and possible involvements were searched. Materials and Methods: A literature search of PubMed database was performed in July 2018 as well as a search of relevant journals and reference lists. The total number of screened articles was 1,422. Some articles were found in multiple different searches. A last PubMed search was performed during manuscript writing in December 2018 to update the knowledge. Eventually 427 articles with full text were evaluated, and 264 included, in this review. Results: There is no real evidence for a possible common etiology for abdominal wall hernias and any cancer type. The two different diseases had been found to have some common points in the studies on genes, integrins, and biomarkers, however, to date no meaningful relationship has been identified between these points. There is also some, albeit rather conflicting, evidence for inguinal hernia being a possible risk factor for testicular cancer. Neoadjuvant or adjuvant therapeutic modalities like chemotherapy and radiotherapy may cause postoperative herniation with their adverse effects on tissue repair. Certain specific substances like bevacizumab may cause more serious complications and interfere with hernia repair. There are only two articles in PubMed directly related to the topic of "hernia and cancer." In one of these the authors claimed that there was no association between cancer development and hernia repair with mesh. The other article reported two cases of squamous-cell carcinoma developed secondary to longstanding mesh infections. Conclusion: As expected, the relationship between abdominal wall hernias and cancer is weak. Hernia repair with mesh does not cause cancer, there is only one case report on cancer development following a longstanding prosthetic material infections. However, there are some intersection points between these two disease groups which are worthy of research in the future.

Identification of a rare LAMB4 variant associated with familial diverticulitis through exome sequencing

Diverticulitis is a chronic disease of the colon in which diverticuli, or outpouching through the colonic wall, become inflamed. Although recent observations suggest that genetic factors may play a significant role in diverticulitis, few genes have yet been implicated in disease pathogenesis and familial cases are uncommon. Here, we report results of whole exome sequencing performed on members from a single multi-generational family with early onset diverticulitis in order to identify a genetic component of the disease. We identified a rare single nucleotide variant in the laminin β 4 gene (LAMB4) that segregated with disease in a dominant pattern and causes a damaging missense substitution (D435N). Targeted sequencing of LAMB4 in 148 non-familial and unrelated sporadic diverticulitis patients identified two additional rare variants in the gene. Immunohistochemistry indicated that LAMB4 localizes to the myenteric plexus of colonic tissue and patients harboring LAMB4 variants exhibited reduced LAMB4 protein levels relative to controls. Laminins are constituents of the extracellular matrix and play a major role in regulating the development and function of the enteric nervous system. Reduced LAMB4 levels may therefore alter innervation and morphology of the enteric nervous system, which may contribute to colonic dysmotility associated with diverticulitis.

Pathophysiology of colorectal peritoneal carcinomatosis: Role of the peritoneum

Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death worldwide. Besides the lymphatic and haematogenous routes of dissemination, CRC frequently gives rise to transcoelomic spread of tumor cells in the peritoneal cavity, which ultimately leads to peritoneal carcinomatosis (PC). PC is associated with a poor prognosis and bad quality of life for these patients in their terminal stages of disease. A loco-regional treatment modality for PC combining cytoreductive surgery and hyperthermic intraperitoneal peroperative chemotherapy has resulted in promising clinical results. However, this novel approach is associated with significant morbidity and mortality. A comprehensive understanding of the molecular events involved in peritoneal disease spread is paramount in avoiding unnecessary toxicity. The emergence of PC is the result of a molecular crosstalk between cancer cells and host elements, involving several well-defined steps, together known as the peritoneal metastatic cascade. Individual or clumps of tumor cells detach from the primary tumor, gain access to the peritoneal cavity and become susceptible to the regular peritoneal transport. They attach to the distant peritoneum, subsequently invade the subperitoneal space, where angiogenesis sustains proliferation and enables further metastatic growth. These molecular events are not isolated events but rather a continuous and interdependent process. In this manuscript, we review current data regarding the molecular mechanisms underlying the development of colorectal PC, with a special focus on the peritoneum and the role of the surgeon in peritoneal disease spread.

Different Types of Periampullary Duodenal Diverticula Are Associated with Occurrence and Recurrence of Bile Duct Stones: A Case-Control Study from a Chinese Center

Aims. We here investigated the association of different types of periampullary diverticula (PAD) with pancreaticobiliary disease and with technical success of endoscopic retrograde cholangiopancreatography (ERCP). Methods. A total of 850 consecutive patients who underwent their first ERCP were entered into a database. Of these patients, 161 patients (18.9%) had PAD and the age- and sex-matched control group comprised 483 patients. Results. PAD was correlated with common bile duct (CBD) stones (59.6% versus 35.0% in controls; P = 0.008) and negatively correlated with periampullary malignancy (6.8% versus 21.5% in controls; P = 0.004). The acute pancreatitis was more frequent (62.5%) in patients with PAD type 1 followed by PAD type 2 (28.9%, P = 0.017) and type 3 (28.0%, P = 0.006). No significant differences were observed in successful cannulation rate and post-ERCP complications among the 3 types of PAD. Type 1 PAD patients had less recurrence of CBD stones than did the patients who had type 2 or type 3 PAD (53.8% versus 85.7%; P = 0.043). Conclusions. PAD, especially type 1 PAD, is associated with an increased acute pancreatitis as well as occurrence and recurrence of CBD stones. PAD during an ERCP should not be considered as an obstacle to a successful cannulation.

Metastasis-associated factors facilitating the progression of colorectal cancer

Tumor metastasis remains the principal cause of treatment failure and poor prognosis in patients with colorectal cancer. It is a multistage process which includes proteolysis, motility and migration of cells, proliferation in a new site, and neoangiogenesis. A crucial step in the process of intra- and extra-vasation is the activation of proteolytic enzymes capable of degrading the extracellular matrix (ECM). In this stage, urokinase plasminogen activator receptor (uPAR) and matrix metalloproteinases (MMPs) are necessary. Micrometastases need the presence of growth factor and vascular growth factor so that they can form macrometastasis. In addition, cell adhesion molecules (CAMs) and guanine nucleotide exchange factors (GEFs) play important roles in the progression of colorectal cancer and metastatic migration. Further elucidation of the mechanisms of how these molecules contribute will aid in the identification of diagnostic and prognostic markers as well as therapeutic targets for patients with colorectal metastasis.

Clinicopathological significance and prognostic value of MMP-13 expression in colorectal cancer

The purpose of this study was to evaluate the association of matrix metalloproteinase-13 (MMP-13) expression with clinicopathological features and prognosis in colorectal cancer (CRC) patients. CRC tissues and distal normal mucosa tissues of 158 CRC patients were detected by immunohistochemistry. The correlations between MMP-13 expression, the patients' clinicopathological features, and overall survival rate were analyzed. It was found that positive expression rate of MMP-13 in distal normal mucosa tissues was significantly lower than that in CRC tissues (36.7% vs 60.8%, p < 0.001). Poor histological differentiation, advanced clinical stage and lymph node metastasis were significantly correlated with the MMP-13 expression in CRC. The overall survival rate of the MMP-13-negative group was significantly higher than the positive group (Log-rank test = 12.452, p < 0.001). Collectively, we found that MMP-13 was correlated with progression and metastasis of CRC and could be used as a prognostic marker in CRC.

Association between colorectal cancer and colonic diverticulosis: case-control study based on computed tomographic colonography

BACKGROUND

The association between colorectal cancer (CRC) and diverticulosis is uncertain, and there is little data reported in Asia. This study examined the association of both diseases based on the computed tomographic colonography (CTC).

METHODS

This study was designed as a case-control study. Korean subjects undergoing CTC between April 2002 to April 2008 in Samsung Medical Center were eligible. Patients with histologically proven colorectal cancer (case group) and asymptomatic age and gender matched controls (control group) were analyzed retrospectively.

RESULTS

A total of 604 subjects were enrolled in this study (Case group N = 302, Control group N = 302). The case group was 54.6% male and the median age was 56.9 years old. Among them 24.5% of CRC patients had diverticulosis compared to 29.5% of controls (P = 0.169). The distribution of diverticulosis between the two groups was similar. Subset analysis revealed no difference in the location of diverticulosis in patients with right colon cancer and left colon cancer (P = 0.781).

CONCLUSIONS

This study indicates that CRC is not associated with diverticulosis.

There is no increased risk for colorectal cancer and adenomas in patients with diverticulitis: a retrospective longitudinal study

AIM

This study was designed to assess the relationship between diverticulitis and the development of colorectal cancer (CRC) and colonic adenomas.

METHOD

A retrospective study was longitudinally conducted. Patients who had been admitted to the hospital between 1990 and 2000 with diverticulitis were retrieved and the incidence of CRC and prevalence of colonic adenomas in these patients was determined. Data were collected from the electronic clinical and pathology records. The incidence of CRC and prevalence of adenomas in this patient cohort was compared with the general population. The patients were followed until 2008.

RESULTS

A total of 288 patients with diverticulitis were included (167 of whom were female patients [58%]). The mean age of patients at admittance for diverticulitis was 66 years (range: 27-92). CRC was detected in five patients (1.7%) (95% CI 0.8-3.5) with a mean age of 77 years; colonic adenomas were found in 18 patients (6.3%) (95% CI 4.3-9.0) with a mean age of 62 years. The lifetime risks of developing CRC and adenomas were presumed to be 4% and 20% respectively. Expected rates for CRC and adenomas in our patients were calculated as 17 (95% CI 4.0-8.6) and 69 patients (95% CI 20.1-28.3) respectively.

CONCLUSION

This study showed a lower prevalence of CRC and colonic adenomas in patients with diverticulitis compared with the lifetime risk which means that diverticulitis is not a risk factor for development of CRC and adenomas. Long-term colonic screening after a negative colonoscopy for diverticulitis (generally performed several weeks after recovery) does not seem to be justified.

Absence of circulating aldosterone attenuates foreign body reaction around surgical sutures

BACKGROUND AND AIMS

Adrenal hormones influence inflammatory and fibrotic activity and thereby are involved in wound-healing process. Any excess as well as any shortage of glucocorticoids leads to a delayed wound healing. Mineralocorticoids like aldosterone have a pro-fibrotic and pro-inflammatory impact; thus, reduction of circulating aldosterone should result in an attenuated inflammatory response to implanted foreign bodies.

MATERIAL AND METHODS

Eighteen rats were bilaterally adrenalectomized and substituted with dexamethasone (12 microg/kg per day) and 1% salt in their drinking water; 22 rats were sham-operated. The surgical suture material was removed after 3 weeks and analyzed for size of granuloma, ratio of collagen type I/III, apoptotic cells (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling), expression of matrix metalloproteinase (MMP)-2, cyclooxygenase 2, tumor necrosis factor receptor 2 (TNF-R2), cluster of differentiation 68 (CD68), Ki67, and cold shock protein Y box binding protein 1 (YB-1). Cell expression was scored according to Remmele.

RESULTS

All animals developed foreign body granulomas around the sutures. Absence of circulating aldosterone after adrenalectomy (ADX) was associated with smaller granuloma size and a reduced ratio of collagen type I/III. Ki67 and MMP-2 showed the strongest expression in cells of the infiltrate around suture. In adrenalectomized rats, we observed significantly less CD68-positive macrophages and less Ki67-positive cells but no significant differences in the expression of YB-1, TNF-R2, or MMP-2. Looking for correlations and co-expressions of proteins, the number of significant Spearman correlations was reduced in the ADX group compared to controls (one and four, respectively).

CONCLUSION

The absence of circulating aldosterone attenuates inflammatory intensity around suture material. Foreign body granuloma seems to be an appropriate model to study chronic inflammatory process.

Diverticulosis and diverticulitis form no risk for polyps and colorectal neoplasia in 4,241 colonoscopies

BACKGROUND AND AIMS

There are conflicting data concerning the association between diverticular disease and colorectal carcinoma (CRC). This study was performed to determine the prevalence and association of diverticulosis, diverticulitis, polyps, and CRC.

MATERIALS AND METHODS

In a cross-sectional, retrospective study, we analyzed the colonoscopy reports of complete colonoscopies and patho-histological results of all patients referred for colonoscopy in a period of 3 months in 18 hospitals in The Netherlands. Diverticulosis was defined as three or more diverticula present and diverticulitis as diverticulosis with inflammation. Polyps were also coded according to localization and size. Advanced neoplastic lesions were defined as polyps >or=10 mm in diameter and/or villous architecture and/or adenomas with high grade dysplasia and/or invasive cancer. Actual and previous described CRC were registered.

RESULTS

A total of 4,241 patients were included in the study [1,996 (47%) male], mean age of 59 and range 18-95. Diverticula, diverticulitis, and polyps were seen in 1,052 (25%), 75 (2%), and 1,282 (30%) patients, respectively. No association was found between patients with polyps and those with and without diverticulosis (p=0.478). Invasive adenocarcinoma and adenomas >or=10 mm were most frequently observed. CRC was present in 372 (9%) patients. Negative relation between diverticulosis and CRC and invasive adenocarcinoma was observed. No association was found between polyps and CRC and patients with diverticulitis and CRC. In conclusion, there is no relation between patients with diverticulosis and higher incidence of polyps or CRC when using age-stratified analysis. No increased risk for polyps or CRC was found in patients with diverticulitis.

Diverticulosis and colorectal cancer: between lights and shadows

The prevalence of diverticulosis and colorectal cancer (CRC) is markedly increased in the last century. Both diseases are highly frequent in Western countries and in aged people. Western diet--low in fiber and rich in dietary fat--has been largely regarded to play a major role in the pathogenesis of both conditions. A causal relationship between diverticulosis and CRC has been suggested in different studies. Epidemiologic series found a more frequent rectosigmoid localization of neoplastic lesions (advanced adenoma and CRC) in patients with diverticulosis as compared with controls, particularly in those with a previous diverticulitis episode or with an extensive disease. However, data are still controversial, with other studies failing to confirm this observation. Such discrepancy could be referred to the highly heterogeneous study design and setting in the different epidemiologic series. Pathologic studies showed that either macroscopic and microscopic chronic inflammation--which is regarded as risk factor for CRC development--is present in the colonic mucosa of some patients with diverticula. Moreover, alterations in the extracellular matrix, also involved in colorectal carcinogenesis, have been depicted in diverticulosis. In addition, an upward shifting of cell proliferation occurs in diverticular mucosa, and in nondiverticular patients with advanced adenomas. Finally, aberrant crypt foci--which are considered potential markers of CRC risk in ulcerative colitis--have been detected in colonic mucosa of patients with diverticulosis. Despite this substantial amount of evidence, however, the available data are not yet strong enough to suggest a more aggressive CRC prevention in diverticular as compared with nondiverticular subjects.

Review article: Management of diverticulitis

BACKGROUND AND AIM

The incidence and therefore complications of (sigmoid) diverticular disease are increasing.

METHODS

Review of current literature.

RESULTS

From all patients, 15% will develop diverticulitis, 5% complications and 5% diverticular bleeding. Diagnosis is established with computerised tomography. Colonoscopy is needed to rule out malignancy. NSAIDs increase the risk of perforation; steroids, diabetes, collagen vascular disease and immune compromised are associated with complicated disease and death. In mild diverticulitis, antibiotics are recommended. In complicated disease with abscesses, <5 cm antibiotics are sufficient. Larger abscesses are drained under computerised tomography-guidance. Peritonitis forms an indication for surgery. Diverticulitis recurrence rate is around 30%, most are uncomplicated. Recurrence after surgery is around 10%. Elective surgery is reserved for fistula closure and obstruction. The need for elective surgery to prevent recurrence has diminished because of new insights. Important is to identify risk groups. New issues are the possible relationship between diverticulitis and cancer, segmental colitis associated with diverticulitis, and treatment of diverticulitis with mesalazine and probiotics.

CONCLUSIONS

Uncomplicated diverticulitis is treated medically. Complicated diverticulitis with small abscesses is treated with antibiotics while larger abscesses are drained with computerised tomography-guided puncture. Emergency surgery is reserved for peritonitis, elective surgery for fistula/stenosis. Surgery to prevent recurrence is indicated only in selected cases (e.g. immune compromised).

ROCK-II mediates colon cancer invasion via regulation of MMP-2 and MMP-13 at the site of invadopodia as revealed by multiphoton imaging

The ROCK-II isoform of Rho's downstream effector, Rho kinase, has been linked with greater invasion and metastasis in solid tumors. We have previously shown that ROCK-II is overexpressed at the advancing edge of colon cancers. The mechanism whereby ROCK-II contributes invasion, particularly in the setting of colon cancer, remains to be elucidated fully. To better understand its contribution, we evaluated ROCK-II expression in both non-malignant (NCM460 and IEC-6) and malignant (Caco-2 E, SW620, and HCT-116) intestinal epithelial cell lines grown in type I collagen scaffolds. Using multiphoton microscopy, we observed that ROCK-II localized to the actin cytoskeleton in non-malignant cells but localized to the cell periphery as focal collections with an absence of adjacent collagen in all colon cancer cell lines. By transmission electron microscopy, these collections corresponded with finger-like projections previously described as invadopodia. Immunogold staining with cortactin, matrix metalloprotease (MMP)-2, -9, and -13 confirmed that these were indeed invadopodia. To further link ROCK-II to colon cancer invasion, we treated non-malignant and malignant intestinal epithelial cell lines with ROCK-II siRNA and evaluated depth of invasion, proliferation, and MMP-2, -9, and -13 activities. The most striking effect was seen in the highly tumorigenic cell lines, SW620 and HCT-116, wherein ROCK-II knockdown resulted in a two-fold or more reduction in invasion. This reduction in invasion was not due to a decrease in cell proliferation, as a significant reduction in proliferation was only observed in the two non-malignant intestinal cell lines. Finally, both MMP-2 and -13 activities were significantly decreased in all colon cancer cell lines. Taken together, these data suggest for the first time that ROCK-II is a critical mediator of colon cancer cell invasion through its modulation of MMP-2 and -13 at the site of invadopodia but regulates proliferation in non-malignant intestinal cells.