Current Research Questions

Current LAM research projects around the world are focusing on answering some of the questions below. The concept of the idea/ hypotheses bank relates to the need to find a way to screen and potentially fund ideas that can translate into clinical advances more efficiently. We are aware that some questions take longer than others to answer and require drastically varying amounts of funding. We are especially interested in providing a means for testing ideas that on their own might not constitute a paper and/ or ideas that can be combined with enough other ideas to round out a research program. We are interested in your feedback and ranking of these ideas. We are interested in your proposals to work on these ideas and related budgets. Please contact us if you would like to submit a proposal addressing the ideas below. We will create and posting and ranking system for these ideas shortly.

BIOMARKERS

Circulating LAM Cells:

• Are circulating cells part of pathogenesis, marker of disease progression? Marker of disease vs. stage?
• Do circulating cells with melanocytic markers in particular decrease in numbers on treatment?
• Detection of other markers by rtPCR assay- look at blood of LAM patients for relative expression of MITF and other markers from circulating cells?

Related project: (Examine Endometrial shedding determine if there is a peak of circulating cells during menstrual cycle –what technique for isolating circulating cells be used to measure levels during cycle?

IMAGING

• PET scan positivity - if LAM and TSC lesions tend not to be PET positive, what would the presence of PET positive lesions once a patient is on treatment tell us? It may be useful in telling us generally that targets are being hit. How useful would that be in assessing response to treatment? (Major investigators state that they do not have PET data from patients on and coming off rapa). Ideally there would be baseline plus PET on drug. Usefulness should be carefully considered.
  
  

EVIDENCE ABOUT HORMONES & OTHER POTENTIAL TRIGGERS OF DISEASE PROGRESSION

• What role do hormones play in the development, proliferation and progression of disease in individuals with LAM, if any?
• How do we explain the role of hormones in LAM?
• Should we be focused on estrogen as the main hormone in question?
• If hormones are not the triggers of disease progression, what are the triggers? Are there other progression-specific triggers of disease?
• Why women? Or conversely, why not men? Is testosterone protective in "preventing" the development of LAM?
• Are women with LAM prone to other diseases?
  
  

CELL OF ORIGIN & MICROENVIRONMENT OF THE LUNG & ITS DESTRUCTION

• What is the cell of origin of the "LAM" cell?
• Is ascertainment bias the only thing accounting for the milder phenotype of LAM in the context of TSC?
• Are hormones responsible for lung destruction in LAM? If so, what is hormonally responsive in the lung? Or, are hormones somehow involved in homing to the lung?
• What in the microenvironment of the lung might affect differentiation of stem cells in the lung? What are the phenotypic differences between seemingly genetically identical cells found in the heart versus the kidney versus the lung?
• Why do cysts develop in the lungs of individuals with LAM? Is this a macro-structural destruction question?
• Is the process of cyst formation different from the invasion of the LAM cells into the lung parenchyma, or are they related? How do you study that process? Are they LAM cells or LAM nodules responsible for these results? Do they line the cysts? What is the causal evidence available on this issue? The cysts and the LAM cells may be correlated but not causal.
• Diffuse dissemination of cysts in lung - when do cells get there? What are the alternative theories? Are there other gender specific diseases that are related to tissue destruction?
• What co-culturing experiments might be interesting to perform to get further along in answering this question? What do leading-edge insights in cell survival, proliferation and even homing teach us?
• If we see airway bronchodilator effect in individuals with more aggressive progression of disease, what does this tell us about the role of inflammation and macrophage activity in LAM given that these have been implicated in enhanced invasiveness via matrix metalloproteases (MMPs) in cancers?
  
  

GENETICS/ GENOMICS:

• Validation/Identification of Mutations: Sequencing both alleles of the TSC genes in LAM cell to identify the various mutations in LAM samples
• Looking for other mutations beyond TSC; Scale up process of isolating LAM DNA to look for mutations beyond TSC (oncomapping) higher density SNP array experiments & Vogelstein's approach looking for additional hits. For oncomapping - comparison with 1000 most common cancer-causing mutations, need DNA from which samples? Oncomap AMLs first ... start with samples but need normals; Start with AMLs available now; go back with micro-dissection. Also use urine to get cell DNA
• Profile/ signature of TSC with AMLs to predict the metastatic potential vs. TSC who develop LAM?
• Analyze 10+ Uterine tumors via histopath and match uterine tumor mutations in AML and LAM/ TSC2/ mutations of AMLs in LAM/ lymphangioleiomyomas
• Expression Data comparison: E.g. compare Morton and Moss gene expression data compare leiomyoma across tumors from neural crest lineages/ nephrogenital ridge
• In women with TSC/LAM, are her LAM cells in the lung coming from second hit present in AMLs in kidney or else where?
• Looking in expression data of stored uterine leiomyoma tissue for nephrogenital ridge markers
  
  

MOLECULAR BIO / SIGNALING/ RECEPTORS

• Is there local production of aromatase? Is there local aromatase activity/production/expression? Look at promoters for aromatase?
• Is PR an mTOR target? Test LAM samples and ELT3 cells
• Which receptors are expressed in LAM cells and supporting cells? Which supporting cells are significant? And what are points of cross-talk with TSC pathway?
• Is there an increase in oxidative stress in the LAM context?
• Experiment: Bathing fresh lung tissue in estrogen
  
  

MODEL-RELATED/ SEX-SPECIFICITY

• Are there two precursor stem cells? One, that leads to AMLs in the kidney in men that do not spread to the lung except in rare instances and another that starts in the uterus as a PEComa or leiomyoma or endometrial stromal derived cell and then goes to the kidney in s-LAM and women with TSC-LAM and also goes to the lung.
• First and second hit in s-LAM happened once and then LAM cells are clonal.
• Seeding from earlier vs. ongoing metastasis is not clear. In women with AMLs removed and 10 years later LAM develops with same TSC2 mutation (migrated or seeded?)? How to test this?
• Get more info from the Eker Rat (look more carefully at metastasis to the lungs; look at spontaneous leiomyomas more closely for PEComA like features);
• Create a TSC2 knock out during Mullerian organigenesis and see if tumor cells are found in the kidney
  
  

PRE-CLINICAL TRANSLATIONAL

• Best surrogate cell and animal models should be used for testing prioritized therapeutic agents even as new models and lines are developed.
  
  

CLINICAL

• Serum biomarker detection– women with LAM vs. normal controls; women with LAM pre and post treatment.
• Scan women with TSC and LAM for presence of clinically significant/sub-clinical uterine lesions or look at uterus tissue/fibroid/leiomyoma/ PEComas.
• 3 newly diagnosed women with s-LAM and image the uterus; isolate blood and identify mutation; biopsy the leiomyomas to see if the same mutation
• 10 specimens from uterine leiomyoma in women with s-LAM or TSC-LAM and compare with typical uterine leiomyoma specimens; Look for abnormal "LAM" cells in the uterus
• Completely wipe out any estrogenic input and determine if arrest or regression. 10 women, use AMLs and PFT as endpoints; any other biomarkers -circulating cells/ VEGF-d
• Prospective study to collect serum during puberty to look at hormone levels and do MRI to study progression of disease and AML burden? Goal: Correlate hormone levels and progression of disease
• Can we get empirical data on circulating hormones during menstrual cycle? Take inventory of temperature, trough at menses, know when the surge is via temperature or time, get luteal surge (identify) and measure levels then, do for 3-4 months to get read of normal levels (for each person)
• Follow-up data on women who discovered they have LAM during pregnancy