In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Hypoxia is associated with human non-small cell lung cancers (NSCLC), which are highly resistant to chemotherapy. The hypoxia inducible factor (HIF) as a transcription factor in response to hypoxia indicates that it could be a novel, tumor-specific target for anticancer therapy. We hypothesized that disruption of HIF pathway through lentiviral vector-mediated HIF-1alpha RNA interference (RNAi) could reverse the hypoxia-induced resistance to chemotherapy.', 'We transfected Human NSCLC cell lines, SPCA1 and A549 with HIF-1alpha specific RNAi lentiviral vectors as well as controls. HIF-1alpha silenced cells [SPCA1/HIF-1alpha(-) and A549/HIF-1alpha(-)] were screened by blasticidin. They were incubated in 19 or 0.5% O2 for 16 h followed by the assessment of chemosensitivity to cisplatin and doxorubicin with MTT and clonogenic assays. Quantitative RT-PCR and Western blot analysis were used to detect the expressions of HIF-1alpha mRNA and protein, respectively. Moreover, flow cytometry was used to monitor the expression of P-glycoprotein.', 'Exposure of SPCA1 and A549 cells to 0.5% O2 significantly increased resistance to cisplatin and doxorubicin, in contrast to cells incubated in normoxia. Transduction of SPCA1 with HIF-1alpha RNAi vector resulted in sequence specific silencing with 87.2 and 84.6% decreases of HIF-1alpha mRNA transcription and 97.3 and 94.8% of protein expressions in normoxia and hypoxia, respectively. Correspondingly, they are 89.2, 89.9% and 97.2, 88.4% decreases in A549 cells. Hypoxia-induced resistance to cisplatin and doxorubicin were reversed in SPCA1/HIF-1alpha(-) and A549/HIF-1alpha(-) cells. There was no significant P-glycoprotein increase induced by hypoxia in NSCLC cells.\Question: Is hypoxia-induced resistance to cisplatin and doxorubicin in non-small cell lung cancer inhibited by silencing of HIF-1alpha gene?
Our studies demonstrated that hypoxia-induced chemoresistance to cisplatin and doxorubicin in NSCLC cells is through the HIF pathway. MDR1 regulation may not be involved in hypoxia-induced chemoresistance. Combining delivery of HIF-1alpha RNAi lentiviral vector with cisplatin-related chemotherapy regimens may enable us to develop more effective strategy for NSCLC therapy.

Context: Poor condition at operation determined by the physiologic POSSUM score is related to postoperative mortality and morbidity of colorectal cancer surgery. This study was designed to analyze the relationship between condition of patients with colorectal cancer at operation and long-term overall survival.', 'A total of 542 patients survived a radical resection for Stages I, II, or III colorectal cancer. Physiologic POSSUM score at surgery, exclusive of age, was calculated for all patients. Mean physiologic POSSUM score was used as cutoff point to determine low-risk and high-risk group patients. A Cox proportional hazard analysis was performed to study the effect of low-risk and high-risk group on overall survival and to identify independent risk factors.', 'Five-year overall survival was significantly higher in low-risk group patients than in high-risk group patients (low-risk group 66.6 percent vs. high-risk group 48.5 percent; P < 0.001). Differences in overall survival also were found when patients in Stages I, II, and III were analyzed separately. Risk factors for overall survival were advanced stage of disease, poor tumor differentiation, mucinous adenocarcinoma, older than age 70 years, and poor condition of the patient at time of operation.\Question: Does pOSSUM predict decreased overall survival in curative resection for colorectal cancer?
Poor condition at operation, as determined by physiologic POSSUM score, is a risk indicator for long-term overall survival in colorectal cancer patients.

Context: To increase the Zn level in shoots, AtHMA4 was ectopically expressed in tomato under the constitutive CaMV 35S promoter. However, the Zn concentration in the shoots of transgenic plants failed to increase at all tested Zn levels in the medium. Modification of Zn root/shoot distribution in tomato expressing 35S::AtHMA4 depended on the concentration of Zn in the medium, thus indicating involvement of unknown endogenous metal-homeostasis mechanisms. To determine these mechanisms, those metal-homeostasis genes that were expressed differently in transgenic and wild-type plants were identified by microarray and RT-qPCR analysis using laser-assisted microdissected RNA isolated from two root sectors: (epidermis\u2009+\u2009cortex and stele), and leaf sectors (upper epidermis\u2009+\u2009palisade parenchyma and lower epidermis\u2009+\u2009spongy parenchyma).', 'Zn-supply-dependent modification of Zn root/shoot distribution in AtHMA4-tomato (increase at 5\xa0μM Zn, no change at 0.5\xa0μM Zn) involved tissue-specific, distinct from that in the wild type, expression of tomato endogenous genes. First, it is suggested that an ethylene-dependent pathway underlies the detected changes in Zn root/shoot partitioning, as it was induced in transgenic plants in a distinct way depending on Zn exposure. Upon exposure to 5 or 0.5\xa0μM Zn, in the epidermis\u2009+\u2009cortex of the transgenics\' roots the expression of the Strategy I Fe-uptake system (ethylene-dependent LeIRT1 and LeFER) was respectively lower or higher than in the wild type and was accompanied by respectively lower or higher expression of the identified ethylene genes (LeNR, LeACO4, LeACO5) and of LeChln. Second, the contribution of LeNRAMP2 expression in the stele is shown to be distinct for wild-type and transgenic plants at both Zn exposures. Ethylene was also suggested as an important factor in a pathway induced in the leaves of transgenic plants by high Zn in the apoplast, which results in the initiation of loading of the excess Zn into the mesophyll of "Zn accumulating cells".\Question: Does engineering high Zn in tomato shoot through expression of AtHMA4 involves tissue-specific modification of endogenous genes?

In transgenic tomato plants, the export activity of ectopically expressed AtHMA4 changes the cellular Zn status, which induces coordinated tissue-specific responses of endogenous ethylene-related genes and metal transporters. These changes constitute an important mechanism involved in the generation of the metal-related phenotype of transgenic tomato expressing AtHMA4.