October 14, 2011 at 11:45 pm #3096HarrisonKeymaster2 pts
Bacterial and fungal microflora in surgically removed lung cancer samples
Clinical and experimental data suggest an association between the presence of bacterial and/or fungal infection and the development of different types of cancer, independently of chemotherapy-induced leukopenia. This has also been postulated for the development of lung cancer, however the prevalence and the exact species of the bacteria and fungi implicated, have not yet been described.
Aim: To determine the presence of bacterial and fungal microflora in surgically extracted samples of patients with lung cancer.
Materials and methods: In this single-center prospective, observational study, tissue samples were surgically extracted from 32 consecutive patients with lung cancer, and reverse-transcription polymerase chain reaction (RT-PCR) was used to identify the presence of bacteria and fungi strains.
Results: The analysis of the electrophoresis data pointed out diversity between the samples and the strains that were identified.
Mycoplasma strains were identified in all samples. Strains that appeared more often were Staphylococcus epidermidis, Streptococcus mitis and Bacillus strains, followed in descending frequency by Chlamydia, Candida, Listeria, and Haemophilus influenza.
In individual patients Legionella pneumophila and Candida tropicalis were detected.
Conclusions: A diversity of pathogens could be identified in surgically extracted tissue samples of patients with lung cancer, with mycoplasma strains being present in all samples. These results point to an etiologic role for chronic infection in lung carcinogenesis.
Confirmation of these observations and additional studies are needed to further characterize the etiologic role of inflammation in lung carcinogenesis.
Author: Panagiotis Apostolou Aggeliki TsantsaridouIoannis PapasotiriouMaria ToloudiMarina ChatziioannouGregory Giamouzis
Credits/Source: Journal of Cardiothoracic Surgery 2011, 6:137
October 25, 2011 at 5:22 pm #3097HarrisonKeymaster2 pts
Colon cancer linked to bacteria: future treatment with antibiotics?
By Deborah Kotz , Globe Staff
A significant percentage of colon cancers could be caused by a bacteria and — if thats indeed the case — some tumors eventually may be prevented or treated with antibiotics, suggests a new research finding from the Broad Institute and Dana-Farber Cancer Institute. Using gene sequencing techniques, the researchers found that areas of the colon where tumors are located were far more likely to contain high levels of Fusobacteria — associated with appendicitis and inflammatory bowel disease — than other portions of the colon in the same patients that didnt contain cancer.
In general, some of the most common bacteria that live in the colon are harmless kinds like e. coli and enterobacteria, said study leader Aleksandar Kostic, a doctoral candidate in biomedicine at Harvard Medical School. But most colon cancer patients had Fusobacterium as the most prevalent type but only in areas where there were tumors. Certain strains of the bacteria are known to cause dangerous inflammation if their growth is unchecked by other bacteria.
In about 10 percent to 15 percent of the 95 patients who participated in the study, Kostic said, more than half of the bacteria in malignant tissue was Fusobacteria. Future studies, he added, need to include at least 1,000 patients to better ascertain whether the association is real.
This wouldnt be the first time that specific bacteria and viruses were implicated in cancer: The sexually transmitted human papillomavirus (HPV) inserts itself into the human genome to trigger cervical cancer and the herpes virus has been associated with the soft tissue cancer Kaposis sarcoma. The bacteria Helicobacter pylori can create an inflammatory environment in the gut that leads to gastric cancer and stomach lymphoma, as well as benign ulcers.
Kostic and his colleagues are currently conducting a study in mice to see if those fed Fusobacteria develop colon tumors at higher rates than those who arent infected. Weve had encouraging results, but our data arent complete yet, he said.
If and when researchers can demonstate that Fusobacteria actually trigger colon cancer, colon cancer patients who test positive for Fusobacteria via a stool sample — such a test now exists — could be treated with antibiotics to see whether they shrink their tumors, Kostic said. Others without colon cancer who test positive for the bacteria, he added, could be treated prophylactically with antibiotics in an effort to lower their risk.
Deborah Kotz can be reached at firstname.lastname@example.org. Follow her on Twitter @debkotz2.
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