Is there a role for prophylactic colectomy in Lynch syndrome patients with inflammatory bowel disease?

PURPOSE: Lynch syndrome and chronic inflammatory bowel disease are two important risk factors for colorectal cancer. It is unclear whether Lynch syndrome patients with inflammatory bowel disease are at sufficiently increased risk for colorectal cancer to warrant prophylactic colectomy. This study aims to identify all cases of Lynch syndrome and concurrent inflammatory bowel disease in a large familial gastrointestinal cancer registry, define incidence of colorectal cancer, and characterize mismatch repair protein gene mutation status and inflammatory bowel disease-associated colorectal cancer risk factors. METHODS: We retrospectively identified and collected clinical data for all cases with confirmed diagnoses of Lynch syndrome and inflammatory bowel disease in the Familial Gastrointestinal Cancer Registry at Mount Sinai Hospital in Toronto, Canada. RESULTS: Twelve cases of confirmed Lynch syndrome, and concurrent inflammatory bowel disease were identified. Four cases developed colorectal cancer. An additional five cases had colectomy; one was performed for severe colitis, and four were performed for low-grade dysplasia. None of these surgical specimens contained malignancy or high-grade dysplasia. CONCLUSIONS: The presentation of Lynch syndrome with inflammatory bowel disease is uncommon and not well described in the literature. This small but important series of twelve cases is the largest reported to date. In this series, patients with Lynch syndrome and concurrent inflammatory bowel disease do not appear to have sufficiently increased risk for colorectal cancer to recommend prophylactic surgery. Therefore, the decision to surgery should continue to be guided by surgical indications for each disease. Further evaluation of this important area will require multi-institutional input.

Integrative genomic and proteomic analyses identify targets for Lkb1-deficient metastatic lung tumors.

In mice, Lkb1 deletion and activation of Kras(G12D) results in lung tumors with a high penetrance of lymph node and distant metastases. We analyzed these primary and metastatic de novo lung cancers with integrated genomic and proteomic profiles, and have identified gene and phosphoprotein signatures associated with Lkb1 loss and progression to invasive and metastatic lung tumors. These studies revealed that SRC is activated in Lkb1-deficient primary and metastatic lung tumors, and that the combined inhibition of SRC, PI3K, and MEK1/2 resulted in synergistic tumor regression. These studies demonstrate that integrated genomic and proteomic analyses can be used to identify signaling pathways that may be targeted for treatment.

Sunitinib prolongs survival in genetically engineered mouse models of multistep lung carcinogenesis.

Non-small cell lung cancer (NSCLC) has a poor prognosis, with substantial mortality rates even among patients diagnosed with early-stage disease. There are few effective measures to block the development or progression of NSCLC. Antiangiogenic drugs represent a new class of agents targeting multiple aspects of tumor progression, including cell proliferation, invasion, migration, and outgrowth of metastatic deposits. We tested the multitargeted angiogenesis inhibitor sunitinib in a novel endogenous mouse model of NSCLC, which expresses a conditional activating mutation in Kras with or without conditional deletion of Lkb1; both alterations are frequent in human NSCLC. We showed that daily treatment with sunitinib reduced tumor size, caused tumor necrosis, blocked tumor progression, and prolonged median survival in both the metastatic (Lkb1/Kras) and nonmetastatic (Kras) mouse models; median survival was not reached in the nonmetastatic model after 1 year. However, the incidence of local and distant metastases was similar in sunitinib-treated and untreated Lkb1/Kras mice, suggesting that prolonged survival with sunitinib in these mice was due to direct effects on primary tumor growth rather than to inhibition of metastatic progression. These collective results suggest that the use of angiogenesis inhibitors in early-stage disease for prevention of tumor development and growth may have major survival benefits in the setting of NSCLC.

Telomere shortening and mood disorders: preliminary support for a chronic stress model of accelerated aging.

BACKGROUND: Little is known about the biological mechanisms underlying the excess medical morbidity and mortality associated with mood disorders. Substantial evidence supports abnormalities in stress-related biological systems in depression. Accelerated telomere shortening may reflect stress-related oxidative damage to cells and accelerated aging, and severe psychosocial stress has been linked to telomere shortening. We propose that chronic stress associated with mood disorders may contribute to excess vulnerability for diseases of aging such as cardiovascular disease and possibly some cancers through accelerated organismal aging. METHODS: Telomere length was measured by Southern Analysis in 44 individuals with chronic mood disorders and 44 nonpsychiatrically ill age-matched control subjects. RESULTS: Telomere length was significantly shorter in those with mood disorders, representing as much as 10 years of accelerated aging. CONCLUSIONS: These results provide preliminary evidence that mood disorders are associated with accelerated aging and may suggest a novel mechanism for mood disorder-associated morbidity and mortality.