Polycythemia vera and LAP

Dark tar

Full Member
Apr 13, 2015
24
0
  1. Medical Student
    Is there a logical reason why LAP is elevated in Polycythemia vera?? I know it's low in CML and high in leukomoid reaction (malignant leukocytes lack the enzyme) however I can't link this to the polycythemia vera. Please help.
     

    Transposony

    Do or do not, There is no try
    5+ Year Member
    2+ Year Member
    7+ Year Member
    Nov 10, 2011
    1,811
    999
    Dagobah
    1. Resident [Any Field]
      Is there a logical reason why LAP is elevated in Polycythemia vera?? I know it's low in CML and high in leukomoid reaction (malignant leukocytes lack the enzyme) however I can't link this to the polycythemia vera. Please help.
      Polycythemia vera has increased number of normal leukocytes. More leukocytes, more Alk Phos.
       
      About the Ads

      Transposony

      Do or do not, There is no try
      5+ Year Member
      2+ Year Member
      7+ Year Member
      Nov 10, 2011
      1,811
      999
      Dagobah
      1. Resident [Any Field]
        Thanks for replying Transposony. Forgive my ignorance but how is a cancer associated with normal cells? If you could explain more I'd be very grateful.
        Thanks
        Polycythemia vera is a myeloproliferative (stem cell) disorder. So there is a neoplastic proliferation and maturation of erythroid, megakaryocytic and granulocytic progenitors.
        There is an up-regulation of the EPO receptors due to mutation in the tyrosine kinase (JAK2) leading to increased production due to clonal hyperplasia of these cells lines in the marrow.
         

        Dark tar

        Full Member
        Apr 13, 2015
        24
        0
        1. Medical Student
          Polycythemia vera is a myeloproliferative (stem cell) disorder. So there is a neoplastic proliferation and maturation of erythroid, megakaryocytic and granulocytic progenitors.
          There is an up-regulation of the EPO receptors due to mutation in the tyrosine kinase (JAK2) leading to increased production due to clonal hyperplasia of these cells lines in the marrow.
          Ah-haaa thanks for clarifying dear Transposony !!! So does ESSENTIAL THROMBOCYTHEMIA have increased LAP as well as it has the same JAK2 gene involved?

          Also isn't haptocorin produced by the salivary glands to bind B12 and protect it from stomach acidity?

          Thanks a lot :)
           

          seminoma

          Full Member
          Aug 9, 2014
          1,976
          1,028
          1. Medical Student
            does it increase the EPO receptor? i thought the jak/stat was downstream of the receptor

            Jak2 is the tyrosine kinase that the EPO receptor signals through. You can stimulate the receptor all you want but if the kinase is blocked nothing will happen.

            Like pouring water into a cup. If I cut out the bottom of your cup you'll never be able to drink from it.
             

            aspiringmd1015

            Full Member
            Mar 5, 2014
            1,098
            102
            1. Medical Student
              right, but Transposony had said that there is an upregulation(ie increased amount of EPO receptors) but i thought the pathogenesis behind PV was a jakstat mutation that made it constitutevely acitve, which would work downstream of the receptor, so the actual # of receptors arent increased, and the jakstat is sending growth signals to the nucleus.
               

              Transposony

              Do or do not, There is no try
              5+ Year Member
              2+ Year Member
              7+ Year Member
              Nov 10, 2011
              1,811
              999
              Dagobah
              1. Resident [Any Field]
                right, but Transposony had said that there is an upregulation(ie increased amount of EPO receptors) but i thought the pathogenesis behind PV was a jakstat mutation that made it constitutevely acitve, which would work downstream of the receptor, so the actual # of receptors arent increased, and the jakstat is sending growth signals to the nucleus.
                That's because it also functions as an obligate chaperone for these receptors in the Golgi apparatus and is responsible for their cell-surface expression.
                 

                Dark tar

                Full Member
                Apr 13, 2015
                24
                0
                1. Medical Student
                  I don't think it increases the receptor expression per se. Rather the mutant JAK-2 kinase is working now without much stimulus from epo (so it is now independant of its ligand). JAK2 is a tyrosine kinase and therefore its effects lead to survival ،maturation and differentiation of the effected stem cell.
                   
                  This thread is more than 6 years old.

                  Your message may be considered spam for the following reasons:

                  1. Your new thread title is very short, and likely is unhelpful.
                  2. Your reply is very short and likely does not add anything to the thread.
                  3. Your reply is very long and likely does not add anything to the thread.
                  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
                  5. Your message is mostly quotes or spoilers.
                  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
                  7. This thread is locked.