Matrix Metalloproteinase-1 and -9 Promoter Polymorphisms Are Not Associated With an Increased Risk of Uterine Leiomyomas in a Japanese Population

Is fibroid heterogeneity a significant issue for clinicians and researchers?

The clinical and scientific literature overwhelmingly deals with fibroids as a single entity or disease. This convenient assumption of homogeneity may be an important oversight given that substantial evidence exists for heterogeneity between fibroids at many levels. Failure to recognize and accommodate fibroid heterogeneity can have significant ramifications for both clinical treatment decisions and research protocol design. The aim of this article is to review the current knowledge of fibroid heterogeneity and to identify key areas where fibroid heterogeneity should be taken into consideration both clinically and when designing research protocols. Uterine leiomyomata display significant and well-documented heterogeneity in symptoms, diagnostic imaging appearance, pathology, genetic background and therapeutic requirements. Additional research is needed to better understand fibroid heterogeneity as it relates to pathogenesis, molecular targets for potential new therapies, patient symptoms and, ultimately, treatment. To this list should also be added heterogeneity of genetics, lifestyle and individual clinical characteristics of the fibroid. Increasingly, an understanding of uterine leiomyoma heterogeneity will be of importance for clinicians who see patients with this common and costly disease.

Functional gene polymorphism of matrix metalloproteinase-1 is associated with benign hyperplasia of myo- and endometrium in the Russian population

AIMS

Estrogen-dependent hyperplasia of myo- and endometrium manifests as uterine leiomyoma or adenomyosis. We studied possible associations between common polymorphisms of matrix metalloproteinase (MMP) genes and clinical features of uterine hyperplasia.

PATIENTS AND METHODS

One hundred seventy female patients with uterine leiomyoma (46.6±0.5 years) were observed. Clinical diagnosis was based on physical examination, ultrasonography, and histological data. MMP-1 (-1607 1G/2G, rs1799750) and MMP-3 (-1171 5A/6A, rs3025058) were genotyped with allele-specific polymerase chain reaction (PCR) of leukocyte DNA. Clinical and genetic data were evaluated using nonparametric statistics.

RESULTS

Distributions of MMP-1 and MMP-3 promoter alleles among patients and population controls were similar and corresponded to the Hardy-Weinberg equilibrium (HWE). Detectable tumor growth and adenomyosis were observed, respectively, in 71% and 55% of cases. Steady-state leiomyoma correlated with a higher prevalence of the MMP-1 1G/1G genotype (p=0.02 by χ(2) test). Accelerated tumor growth correlated with higher frequency of the MMP-1 2G allele [odds ratio (OR)=2.048, p=0.039, χ(2)=4.2611, confidence interval (CI)=(1.032-4.062)]. MMP-1 2G was also associated with multinodular growth [OR=3.561, p=0.01249, χ(2)=6.24, CI=(1.261-10.058)]. The MMP-1 2G allele tended to increase in patients with adenomyosis [OR=1.525, p=0.054, χ(2)=3.71, CI=(0.992-2.345)].

CONCLUSION

Our pilot study suggests that the 2G (-1607)MMP-1 genotype may be a potential risk marker of myo- and endometrial hyperplasia.

Note: high-pressure generation using nano-polycrystalline diamonds as anvil materials

Nano-polycrystalline diamonds (NPDs) consist of nanosized diamond grains oriented in random directions. They have high toughness and isotropic mechanical properties. A NPD has neither the cleavage feature nor the anisotropy of hardness peculiar to single-crystal diamonds. Therefore, it is thought to be useful as a diamond anvil. We previously reported the usefulness of a NPD as an anvil for high-pressure development. In this study, some additional high-pressure generating tests using diamond anvils of various shapes prepared from NPDs were conducted to investigate the advantage of using NPDs for anvil applications. The results revealed that the achievable pressure value of a NPD anvil with a culet size of more than 300 μm is about 1.5 to 2 times higher than that of single-crystal diamond anvils, indicating that NPD anvils have considerable potential for large-volume diamond anvils with large culet sizes.

Proinflammatory and profibrotic mediators: principal effectors of leiomyoma development as a fibrotic disorder

Leiomyomas are believed to derive from the transformation of myometrial smooth muscle cells/connective tissue fibroblasts. Although the identity of the molecule(s) that initiate such cellular transformation and orchestrate subsequent growth is still unknown, conventional evidence indicates that ovarian steroids are essential for leiomyoma growth. Ovarian steroid action in their target cell/tissue is mediated in part through local expression of various growth factors, cytokines, and chemokines. These autocrine/paracrine molecules with proinflammatory and profibrotic activities serve as major contributing factors in regulating cellular transformation, cell growth and apoptosis, angiogenesis, cellular hypertrophy, and excess tissue turnover, events central to leiomyoma growth. This review addresses the key regulatory functions of proinflammatory and profibrotic mediators and their molecular mechanisms, downstream signaling that regulates cellular events that result in transformation, and commitments of specific cells into forming a cellular environment with a possible role in development and subsequent growth of leiomyomas.

Meta-analysis of association between matrix metalloproteinases 2, 7 and 9 promoter polymorphisms and cancer risk

Matrix metalloproteinase (MMP) 2, MMP7 and MMP9 are important members of the MMP family. Four polymorphisms in the promoter region of these MMPs, which are MMP2 -1306 C>T, MMP2 -735 C>T, MMP7 -181 A>G and MMP9 -1562 C>T, have been reported to be functional and may contribute to genetic susceptibility to cancers. However, the associations between these polymorphisms and cancer risk remain inconclusive due to conflicting results from different case-control studies. To better evaluate the role of these polymorphisms in cancer development, we conducted a meta-analysis that included 51 studies, with more than 40,000 subjects. The results showed that under dominant genetic model, MMP2 -1306 T was associated with lower susceptibility to lung cancer [odds ratio (OR) = 0.50, 95% confidence interval (CI) 0.43-0.59, P(heterogeneity) = 0.147, I(2) = 44.1%], head and neck cancer (OR = 0.53, 95% CI 0.41-0.69, P(heterogeneity) = 0.974, I(2) = 0.0%) and oesophageal cancer (OR = 0.67, 95% CI 0.55-0.80, P(heterogeneity) = 0.593, I(2) = 0.0%); MMP2-735T was associated with lower risk in lung cancer (OR = 0.65, 95%CI 0.53-0.79, P(heterogeneity) = 0.42, I(2) = 0.0%) and oesophageal cancer (OR = 0.84, 95% CI 0.70-0.99, P(heterogeneity) = 0.206, I(2) = 37.4%); MMP7 -181 AG and GG genotype carriers had an increased gastric cancer risk (OR = 1.90, 95% CI 1.43-2.51, P(heterogeneity) = 0.992, I(2) = 0.0%) and MMP9 -1562 C>T was not associated with cancer risk in the whole group analysis (OR = 0.99, 95% CI 0.91-1.08, P(heterogeneity) = 0.419, I(2) = 3.0%) and subgroup analyses. In all, our meta-analysis suggests that MMP2 -1306 C>T, MMP2 -735 C>T and MMP7 -181 A>G may play allele-specific roles in cancer development, while MMP9 -1562 C>T may not be a major risk factor for most cancer types. Large case-control studies should be performed to clarify the possible roles of these four polymorphisms in different kinds of cancer in more detail.