Potential Influence of Age and Diabetes Mellitus Type 1 on MSH2 (MutS homolog 2) Expression in a Rat Kidney Tissue.

BACKGROUND: Homeostasis of proliferating tissues is strongly dependent on intact DNA. Both neoplastic and non-neoplastic diseases have been associated with MSH2 (MutS homolog 2, a mismatch repair protein) deficiency. In this study, we examined how age and diabetes mellitus influence the expression of MSH2 in the kidney. METHODS: To study the effect of age, three groups of healthy rats were formed: 2 months, 8 months, and 14 months old. Two groups of diabetic rats were formed: 8 months old and 14 months old. Expression of MSH2 in the kidney was studied by quantifying immunofluorescent staining. RESULTS: Age was identified as the main factor that influences MSH2 expression in kidneys. The effect of age followed parabolic dynamics, with peak expression at 8 months of age and similar levels at 2 and 14 months. Diabetes had an age-dependent effect, which manifested as the increase of MSH2 expression in 14-month-old diabetic rats in comparison to healthy animals. CONCLUSIONS: Age influences MSH2 expression in the kidney more than diabetes mellitus. Since ageing is a risk factor for kidney neoplasia, downregulation of MSH2 in older rats might represent one of the pro-oncogenic mechanisms of ageing at a molecular level.

Plasma levels and tissue expression of soluble TGFßrIII receptor in women with early-stage breast cancer and in healthy women: a prospective observational study.

BACKGROUND: Mammary carcinogenesis is partly regulated by the transforming growth factor beta (TGFß) signaling pathway. Its function in cancer progression and metastasis is highly dependent on disease stage, and it is likely modulated by the ratio of membrane-bound vs. soluble TGFßrIII (sTGFßrIII). In this prospective observational study, we assessed tissue expression and plasma levels of sTGFßrIII in healthy women, women with benign breast lesions and in early-stage breast cancer patients. METHODS: In a preliminary study, plasma sTGFßrIII levels were determined in 13 healthy women (age 19-40 years) at different phases of the ovarian cycle, and in 15 patients (age 35-75 years) at different times of the day. The main study assessed plasma concentrations of sTGFßrIII in: (i) 158 healthy women in whom breast lesions were excluded; (ii) 65 women with benign breast lesions; (iii) 147 women with newly diagnosed breast cancer classified as American Joint Committee on Cancer (AJCC) stages 0 to IIB. Completers provided blood samples before surgery and at 10-30 and 160-180 days after surgery. Plasma sTGFßrIII concentrations were determined using an indirect ELISA kit. Part of the removed tissues underwent immunohistochemical (IHC) staining and analysis of tissue TGFßrIII expression. RESULTS: There appeared no relevant variations in plasma sTGFßrIII levels at different times of the day or different ovarian cycle phases. Before surgery, breast cancer patients had somewhat higher sTGFßrIII than healthy women, or those with benign breast lesions (by 14.5 and 26 ng/mL, respectively), with a tendency of larger differences at higher age. This correlated with lower expression of TGFßrIII in breast cancer vs. healthy tissue samples. At 160-180 days after surgery, plasma sTGFßrIII levels in breast cancer patients declined by 23-26 ng/mL. CONCLUSIONS: Plasma sTGFßrIII levels do not seem to relevantly vary during the day or the ovarian cycle. The coinciding higher plasma levels in newly diagnosed cancer patients than in healthy subjects and lower TGFßrIII expression in the malignant than in healthy breast tissue suggest ectodomain shedding as a source of circulating sTGFßrIII. Decline in plasma levels after tumor removal supports such a view.

Elevated plasma RANTES in fibrodysplasia ossificans progressiva - A novel therapeutic target?

Fibrodysplasia ossificans progressiva (FOP) is a rare hereditary disease caused by a mutation in the intracellular domain of the activin A receptor type I and is characterized by episodes (flare-ups) of progressive heterotopic endochondral ossification (HO) in the soft tissues. The mutation alone is not sufficient for the occurrence of HO since flare-ups are triggered by inflammation and activation of the innate immune system. A number of cellular and humoral mediators have been implicated in animal and in vitro models. Observations in humans support the inflammatory nature of the condition, but data on the involved mediators are variable. We hypothesize that for induction of flare-ups in patients with FOP increase in at least one of the pro-inflammatory cytokines is both essential and sufficient to trigger the entire process of the inflammatory cells influx resulting in the novel ectopic bone formation and we suggest that C-C motif ligand 5 (CCL5), a pro-inflammatory chemokine also known as Regulated on activation, normal T-cell expressed and secreted (RANTES), might be the key candidate. CCL5 is a chemoattractant for all cellular types implicated in HO and is produced by the cells of the tissue microenvironment at the sites of HO as well as by the pro-inflammatory cellular mediators. CCL5 induces ossification in cultured human pluripotent mesenchymal cells (hMSCs) and in the primary culture of monocytes from FOP patients (but not from their healthy relatives), stimulation with lipopolysaccharide induces CCL5 expression. Finally, in a pilot study we used a panel of 23 cytokines and chemokines to screen the plasma samples of three subjects: a female patient with FOP during a flare-up; a female patient with hyperostosis corticalis generalisata (van Buchem disease), another rare disease characterized by excessive bone formation at the sites where it regularly occurs that does not include inflammatory events; and a healthy woman without bone disorders. There appeared a rather clear-cut signal of a 2-fold higher level of CCL5 in the FOP patient vs. the healthy subject and the van Buchem patient. Evaluation of the hypothesis would require an international prospective study, with main motivation being the lack of a conclusive treatment as the major unmet need in FOP. A treatment targeting CCL5 receptor already exists and is used in HIV-infected patients.