Cancer stem cells in Helicobacter pylori infection and aging: Implications for gastric carcinogenesis.

AIM: To demonstrated the combined effects of aging and carcinogen treatment on cancer stem/stem-like cells (CSCs) of gastric mucosa in an animal model. METHODS: In this study we investigated the effects of aging and Helicobacter pylori (H. pylori) inflammation as a model for inflammation induced carcinogenesis in human and rat gastric mucosa samples. In aging studies, we compared 4-mo old (young) with 22 mo (aged) old Fischer-344 rats. For human studies, gastric biopsies and resection specimens representing normal mucosa or different stages of H. pylori gastritis and gastric adenocarcinomas were used for determining the expression of stem cell markers CD166, ALDH1 and LGR5. In addition we performed immunofluorescent double labeling for B-catenin and Lgr5 in both rat and human gastric tissues to examine the status of Wnt signaling in these cells. RESULTS: CSC markers ALDH1, LGR5, and CD166 were expressed in very low levels in normal human gastric mucosa or young rat gastric mucosa. In contrast, level of expression for all three markers significantly increased in H. pylori gastritis and gastric adenocarcinomas as well as in normal gastric mucosa in aged rats. We also observed cytoplasmic B-catenin staining in both aged rat and human H. pylori inflamed gastric mucosa, which were found to be colocalized with Lgr5 immunoreactive cells. The increased number of ALDH1, CD166 and LGR5 positive cells in H. pylori gastritis indicates that increased number of stem-like cells in gastric mucosa is an early event, and may constitute an important step in the progression to neoplasia. CONCLUSION: Our observation of the age-related increase in cancer stem/stem-like cells in the gastric mucosa may explain the increased incidence of gastric cancer during aging. Combination of aging and H. pylori infection may have additive effects in progression to neoplasia.

Squamous cell carcinoma complicating chronic suppurative hydradenitis.

A 69-year-old male patient underwent excision of hidradenitis suppurativa (HS) affecting both gluteal areas and the perineum. The perineal specimen contained a 1-cm superficially invasive, well-differentiated keratinizing squamous cell carcinoma. The patient was free of recurrence 1 year after surgery. A 66-year-old male patient was diagnosed with massive perineal HS more than 40 years previously. More than 30 abscesses and suppurative sinus tracts were surgically treated over the years. He eventually died of unresectable pelvic squamous carcinoma. Search of the literature and available bibliography revealed 47 retrospective studies of skin carcinoma arising in HS since 1959, including a total of 64 patients together with the two patients treated by our team. Squamous cell carcinoma is a rare but potentially fatal complication of HS. Surgery is the only known treatment method that provides a real chance for cure for both HS and a carcinoma that complicates it. HS must be treated early with complete excision to avoid chronic progression of the disease that can cause cancerous degeneration. A high index of suspicion, early tissue diagnosis, and immediate referral for radical surgery carry the only hope for cure in those whose HS harbors malignancy.

Colorectal cancer in the cotton top tamarin (Saguinus oedipus): how do they evade liver metastasis?

BACKGROUND AND AIM: A major cause of cancer-related deaths is the development of liver metastasis. To better understand the metastatic process, we studied the cotton top tamarin as an animal model, which spontaneously develops colorectal cancer but rarely liver metastasis. METHOD: DNA was extracted from primates and Hot-Start PCR was performed. Sequencing was achieved with Big-Dye Terminator™ Sequencing Kit. Tissue expression and glycosylation studies were also performed for carcinoembryonic antigen family proteins. RESULTS: Sixty-three percent of tamarin carcinoembryonic antigen had PELPK changes essential for carcinoembryonic antigen hepatic uptake. Tamarin carcinoembryonic antigen showed minimal glycosylation. Cotton top tamarin livers showed reduced carcinoembryonic antigen-receptor expression and were devoid of CEACAM1 (BGP) as compared to human liver despite positive expression in cotton top tamarin gallbladder mucosa. Peritumoral regions showed more CEACAM1 in human hepatocyte cytoplasm than in biliary canaliculi (P < 0.05). Therefore, tamarins may evade liver metastasis through mechanisms of decreased hepatic uptake by altered PELPK sequences, reduced glycosylation and reduced carcinoembryonic antigen-receptor expression. Furthermore, the absence of cotton top tamarin hepatocyte CEACAM1 may lead to alteration of the liver milieu creating an inhospitable "infertile-field" for metastases. CONCLUSIONS: Four hypotheses explain a complex mechanism for the lack of liver metastasis: (1) carcinoembryonic antigen PELPK-encoding nucleotide sequence changes, (2) minimal carcinoembryonic antigen glycosylation, (3) reduced carcinoembryonic antigen-receptor expression, and (4) reduced CEACAM1 distribution, a putative vascular endothelial growth factor. While these hypotheses are not necessarily causal they are testable and therefore are feasible targets for prevention of hepatic metastasis in man.