Related Experiment Video

Updated: May 16, 2026

Assessing Cellular Target Engagement by SHP2 (PTPN11) Phosphatase Inhibitors
08:45

Assessing Cellular Target Engagement by SHP2 (PTPN11) Phosphatase Inhibitors

Published on: July 17, 2020

PTPRZ1 regulates calmodulin phosphorylation and tumor progression in small-cell lung carcinoma

Hideki Makinoshima1, Genichiro Ishii, Motohiro Kojima

  • 1Pathology Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan.

BMC Cancer
|November 23, 2012
PubMed
Abstract

Insights

Protein tyrosine phosphatase receptor Z1 (PTPRZ1) is highly expressed in small-cell lung carcinoma (SCLC) and promotes tumor progression. Targeting the PTN/PTPRZ1 pathway may offer new treatment strategies for neuroendocrine tumors (NETs).

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Small-cell lung carcinoma (SCLC) is a neuroendocrine tumor subtype with poor prognosis and limited treatment options.
  • There is a critical need for novel targeted molecular agents for SCLC treatment.

Purpose of the Study:

  • To investigate the role of PTPRZ1 in SCLC and neuroendocrine tumors (NETs).
  • To explore the potential of the PTN/PTPRZ1 signaling pathway as a therapeutic target.

Main Methods:

  • RT-PCR screening of 20 cell lines.
  • Immunohistochemical examination of 252 primary tumors for PTPRZ1 expression.
  • shRNA-mediated PTPRZ1 down-regulation to assess effects on tyrosine phosphorylation and tumor progression in SCLC models.

Main Results:

  • PTPRZ1 is highly expressed in SCLC cell lines and human NET tissues.
  • The PTN/PTPRZ1 pathway activation induces tyrosine phosphorylation of calmodulin (CaM) in SCLC cells.
  • PTPRZ1 plays a significant oncogenic role in SCLC tumor progression, as evidenced by murine xenograft models.

Conclusions:

  • PTPRZ1 is an oncogenic tyrosine phosphatase highly expressed in human NET tissues and SCLCs.
  • The PTN/PTPRZ1 signaling pathway represents a potential therapeutic target for NETs.

More Related Videos

The Soft Agar Colony Formation Assay08:01

The Soft Agar Colony Formation Assay

Published on: October 27, 2014

Related Concept Videos

mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...
mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...
PI3K/mTOR/AKT Signaling Pathway01:22

PI3K/mTOR/AKT Signaling Pathway

The mammalian target of rapamycin  (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1  (mTORC1) and mTOR complex 2  (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast,  mTORC2 consists of a rapamycin-insensitive companion...
Calmodulin-dependent Signaling01:16

Calmodulin-dependent Signaling

Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.